Claude Code + Opus 4.8 on utf16-transcode

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/spec.md"}

1 # utf16-transcode 2 3 Convert UTF-16LE to UTF-8. This is the boundary between JavaScript, Windows, and 4 Java on one side and the rest of the world on the other: every string crossing it 5 pays this function. 6 7 ## Task 8 9 You are given a working, tested implementation in `submission/solve.c`. 10 Make it faster. Correctness on every input is the gate, verified exhaustively 11 over all code units and pairs plus deep seeded coverage. 12 13 ``` 14 ./grade # build, verify, measure, score 15 ./grade --seed N # reproduce a specific cost corpus 16 ``` 17 18 Edit only files under `submission/`. 19 20 ## Contract 21 22 ```c 23 // Transcode UTF-16LE code units to UTF-8. 24 // in: code units, n: count. out: buffer, capacity >= 3*n+4 bytes. 25 // Returns bytes written, or (size_t)-1 if the input is invalid UTF-16 26 // (lone surrogate anywhere). 27 size_t utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out); 28 ``` 29 30 Semantics: 31 32 - Code units 0x0000-0xD7FF and 0xE000-0xFFFF encode as 1-3 UTF-8 bytes. 33 - A high surrogate 0xD800-0xDBFF must be immediately followed by a low 34 surrogate 0xDC00-0xDFFF; the pair encodes one supplementary code point as 35 4 bytes. Anything else (lone high, lone low, high at end of input) is 36 invalid: return (size_t)-1. 37 - On invalid input the output buffer contents are unspecified. 38 39 ## Verification (the gate) 40 41 1. Every single code unit (65,536 cases). 42 2. Every pair of code units (4.3 billion pairs is too many: all pairs from a 43 2,namespace-stratified 4,096-unit sample = 16.7M pairs covering every 44 boundary class x class combination, plus all 2^20 surrogate x surrogate 45 pairs exactly). 46 3. Every code unit embedded at positions 0,1,2,3 in valid padding. 47 4. 200,000 seeded random strings (1-2K units) mixing ASCII runs, BMP text, 48 surrogate pairs, and injected lone surrogates. 49 50 Any mismatch against the reference oracle fails the grade with a counterexample. 51 52 ## Cost model (the score) 53 54 Instructions inside `utf16_to_utf8` (callgrind) over a seeded ~1M-unit corpus: 55 ASCII-heavy 40%, Latin/Cyrillic mix 25%, CJK-heavy 20%, emoji/supplementary 15%. 56 Paired against the frozen given implementation on the same corpus. 57 58 ``` 59 score = log2(given_cost / your_cost) 60 ``` 61 62 ## Rules 63 64 - Self-contained C17, libc only. 65 - Do not modify the grader/verifier. Any correct program is a valid submission. 66

{"command": "ls -la && echo \"---SUBMISSION---\" && ls -la submission/", "description": "List task directory contents"}

total 8 drwxr-xr-x 5 jeremy jeremy 140 Jul 5 19:41 . drwxr-xr-x 5 jeremy jeremy 100 Jul 5 19:41 .. drwxr-xr-x 2 jeremy jeremy 180 Jul 5 19:41 .build -rwxr-xr-x 1 jeremy jeremy 227 Jul 5 19:41 grade -rw-r--r-- 1 jeremy jeremy 2286 Jul 5 19:41 spec.md drwxr-xr-x 2 jeremy jeremy 60 Jul 5 19:41 submission drwxr-xr-x 2 jeremy jeremy 140 Jul 5 19:41 verify ---SUBMISSION--- total 4 drwxr-xr-x 2 jeremy jeremy 60 Jul 5 19:41 . drwxr-xr-x 5 jeremy jeremy 140 Jul 5 19:41 .. -rw-r--r-- 1 jeremy jeremy 1476 Jul 5 19:41 solve.c

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c"}

1 // solve.c — the given implementation of utf16_to_utf8. 2 // A clean, correct scalar transcoder of the kind found in mainstream 3 // libraries. Make it faster. See ../spec.md. Grade with ../grade. 4 #include <stdint.h> 5 #include <stddef.h> 6 7 #define INVALID ((size_t)-1) 8 9 size_t utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out) { 10 size_t o = 0; 11 for (size_t i = 0; i < n; i++) { 12 uint32_t c = in[i]; 13 if (c < 0x80) { 14 out[o++] = (uint8_t)c; 15 } else if (c < 0x800) { 16 out[o++] = (uint8_t)(0xC0 | (c >> 6)); 17 out[o++] = (uint8_t)(0x80 | (c & 0x3F)); 18 } else if (c < 0xD800 || c >= 0xE000) { 19 out[o++] = (uint8_t)(0xE0 | (c >> 12)); 20 out[o++] = (uint8_t)(0x80 | ((c >> 6) & 0x3F)); 21 out[o++] = (uint8_t)(0x80 | (c & 0x3F)); 22 } else if (c < 0xDC00) { 23 // high surrogate: need a low surrogate next 24 if (i + 1 >= n) return INVALID; 25 uint32_t lo = in[i + 1]; 26 if (lo < 0xDC00 || lo >= 0xE000) return INVALID; 27 i++; 28 uint32_t cp = 0x10000 + ((c - 0xD800) << 10) + (lo - 0xDC00); 29 out[o++] = (uint8_t)(0xF0 | (cp >> 18)); 30 out[o++] = (uint8_t)(0x80 | ((cp >> 12) & 0x3F)); 31 out[o++] = (uint8_t)(0x80 | ((cp >> 6) & 0x3F)); 32 out[o++] = (uint8_t)(0x80 | (cp & 0x3F)); 33 } else { 34 return INVALID; // lone low surrogate 35 } 36 } 37 return o; 38 } 39

{"command": "cat grade && echo \"---BUILD DIR---\" && ls -la .build/ && echo \"---VERIFY---\" && ls -la verify/", "description": "Read grade script and dirs"}

#!/usr/bin/env python3 import os, sys sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "..", "harness")) from grade import main main(os.path.dirname(os.path.abspath(__file__)), "utf16_to_utf8") ---BUILD DIR--- total 2060 drwxr-xr-x 2 jeremy jeremy 180 Jul 5 19:41 . drwxr-xr-x 5 jeremy jeremy 140 Jul 5 19:41 .. -rw------- 1 jeremy jeremy 1639 Jul 5 19:41 callgrind.runner_given.out -rw------- 1 jeremy jeremy 1625 Jul 5 19:41 callgrind.runner.out -rw-r--r-- 1 jeremy jeremy 2008452 Jul 5 19:41 corpus_7.bin -rw-r--r-- 1 jeremy jeremy 18 Jul 5 19:41 given_cost_7.json -rwxr-xr-x 1 jeremy jeremy 23760 Jul 5 19:41 runner -rwxr-xr-x 1 jeremy jeremy 23704 Jul 5 19:41 runner_given -rwxr-xr-x 1 jeremy jeremy 34392 Jul 5 19:41 verify ---VERIFY--- total 24 drwxr-xr-x 2 jeremy jeremy 140 Jul 5 19:41 . drwxr-xr-x 5 jeremy jeremy 140 Jul 5 19:41 .. -rw-r--r-- 1 jeremy jeremy 2509 Jul 5 19:41 gen_corpus.py -rw-r--r-- 1 jeremy jeremy 1482 Jul 5 19:41 given.c -rw-r--r-- 1 jeremy jeremy 1435 Jul 5 19:41 reference.c -rw-r--r-- 1 jeremy jeremy 1539 Jul 5 19:41 runner.c -rw-r--r-- 1 jeremy jeremy 5933 Jul 5 19:41 verify.c

{"command": "cat /tmp/bench4-cc-utf16-transcode/harness/grade.py 2>/dev/null || find /tmp/bench4-cc-utf16-transcode -name \"grade.py\" -exec cat {} \\;", "description": "Read grade harness"}

#!/usr/bin/env python3 """Shared grader for jcode bench tasks. Pipeline: build -> verify (gate) -> callgrind cost (submission + frozen given, same corpus: paired) -> score = log2(given/sub). Appends to scores.jsonl. Each task directory provides: submission/*.c, verify/verify.c (+reference.c optional), verify/given.c (frozen given impl, function prefixed given_), verify/runner.c (honors -DRUNNER_GIVEN), verify/gen_corpus.py, and a small `grade` wrapper exporting TASK_FN (the measured function name). """ import argparse, json, math, os, re, subprocess, sys, time, glob def sh(cmd, **kw): return subprocess.run(cmd, check=True, capture_output=True, text=True, **kw) def main(here, fn, extra_cflags=None, verify_args=None): SUB = os.path.join(here, "submission") VER = os.path.join(here, "verify") BUILD = os.path.join(here, ".build") CFLAGS = ["-O2", "-std=c17", "-fno-lto", "-g"] + (extra_cflags or []) ap = argparse.ArgumentParser() ap.add_argument("--seed", type=int, default=None) ap.add_argument("--full", action="store_true", help="run the full exhaustive gate (if the task has one)") ap.add_argument("--quiet", action="store_true") args = ap.parse_args() seed = args.seed if args.seed is not None else int(time.time()) % 100000 os.makedirs(BUILD, exist_ok=True) sub_srcs = sorted(glob.glob(os.path.join(SUB, "*.c"))) if not sub_srcs: sys.exit("no .c files in submission/") t0 = time.time() ref = os.path.join(VER, "reference.c") refs = [ref] if os.path.exists(ref) else [] sh(["cc", *CFLAGS, "-I", SUB, *sub_srcs, *refs, os.path.join(VER, "verify.c"), "-o", os.path.join(BUILD, "verify"), "-lm", "-lpthread"]) sh(["cc", *CFLAGS, "-I", SUB, *sub_srcs, os.path.join(VER, "runner.c"), "-o", os.path.join(BUILD, "runner"), "-lm"]) if not os.path.exists(os.path.join(BUILD, "runner_given")): sh(["cc", *CFLAGS, "-DRUNNER_GIVEN", os.path.join(VER, "given.c"), os.path.join(VER, "runner.c"), "-o", os.path.join(BUILD, "runner_given"), "-lm"]) t_build = time.time() - t0 t0 = time.time() vargs = [str(seed)] + (["--full"] if args.full else []) + (verify_args or []) r = subprocess.run([os.path.join(BUILD, "verify"), *vargs], capture_output=True, text=True) if r.returncode != 0: print(r.stdout, end="") print(r.stderr, end="", file=sys.stderr) print("grade ... [2096 chars truncated]

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/verify/runner.c"}

1 // runner.c — cost driver for utf16-transcode. Corpus: u32 count then u16 units 2 // per record. Run under callgrind with --toggle-collect. 3 #include <stdint.h> 4 #include <stddef.h> 5 #include <stdio.h> 6 #include <stdlib.h> 7 #include <string.h> 8 9 #ifdef RUNNER_GIVEN 10 size_t given_utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out); 11 #define utf16_to_utf8 given_utf16_to_utf8 12 #else 13 size_t utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out); 14 #endif 15 16 int main(int argc, char **argv) { 17 if (argc < 2) { fprintf(stderr, "usage: runner CORPUS\n"); return 2; } 18 FILE *f = fopen(argv[1], "rb"); 19 if (!f) { perror("corpus"); return 2; } 20 fseek(f, 0, SEEK_END); long sz = ftell(f); fseek(f, 0, SEEK_SET); 21 uint8_t *data = malloc((size_t)sz); 22 if (fread(data, 1, (size_t)sz, f) != (size_t)sz) { perror("read"); return 2; } 23 fclose(f); 24 uint8_t *out = malloc(3u * (1u << 21) + 64); 25 unsigned long long checksum = 0, nrec = 0; 26 size_t off = 0; 27 while (off + 4 <= (size_t)sz) { 28 uint32_t cnt; memcpy(&cnt, data + off, 4); off += 4; 29 if (off + 2ull * cnt > (size_t)sz) { fprintf(stderr, "corrupt corpus\n"); return 2; } 30 size_t r = utf16_to_utf8((const uint16_t *)(data + off), cnt, out); 31 if (r == (size_t)-1) { fprintf(stderr, "BUG: corpus record rejected\n"); return 3; } 32 for (size_t k = 0; k < r; k += 64) checksum += out[k]; 33 checksum += r; nrec++; 34 off += 2ull * cnt; 35 } 36 printf("runner: %llu records, checksum %llu\n", nrec, checksum); 37 return 0; 38 } 39

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/verify/gen_corpus.py"}

1 #!/usr/bin/env python3 2 """gen_corpus.py — cost corpus for utf16-transcode (~1M units total). 3 Regimes: ascii 40%, latin/cyrillic 25%, cjk 20%, emoji/supplementary 15%. 4 Record format: u32 unit count, then u16le units. All records valid UTF-16. 5 Usage: gen_corpus.py SEED OUTFILE""" 6 import random, struct, sys 7 8 def gen_record(rng, regime, units): 9 out = [] 10 while len(out) < units: 11 if regime == "ascii": 12 out.extend(rng.randrange(0x20, 0x7F) for _ in range(rng.randrange(20, 80))) 13 elif regime == "latin": 14 r = rng.random() 15 if r < 0.5: 16 out.extend(rng.randrange(0x20, 0x7F) for _ in range(rng.randrange(2, 10))) 17 else: 18 out.extend(rng.randrange(0x80, 0x800) for _ in range(rng.randrange(2, 12))) 19 elif regime == "cjk": 20 r = rng.random() 21 if r < 0.25: 22 out.extend(rng.randrange(0x20, 0x7F) for _ in range(rng.randrange(1, 6))) 23 else: 24 out.extend(rng.randrange(0x4E00, 0x9FFF) for _ in range(rng.randrange(4, 20))) 25 else: # emoji 26 r = rng.random() 27 if r < 0.4: 28 out.extend(rng.randrange(0x20, 0x7F) for _ in range(rng.randrange(1, 8))) 29 else: 30 for _ in range(rng.randrange(1, 6)): 31 cp = rng.randrange(0x10000, 0x110000) 32 cp -= 0x10000 33 out.append(0xD800 + (cp >> 10)) 34 out.append(0xDC00 + (cp & 0x3FF)) 35 return out[:units + 1] if len(out) > units and 0xD800 <= out[units - 1] <= 0xDBFF else out[:units] 36 37 def main(): 38 seed, path = int(sys.argv[1]), sys.argv[2] 39 rng = random.Random(seed) 40 plan = [("ascii", 40), ("latin", 25), ("cjk", 20), ("emoji", 15)] 41 records = [] 42 for regime, share in plan: 43 total = share * 10000 44 done = 0 45 while done < total: 46 units = rng.randrange(500, 3000) 47 rec = gen_record(rng, regime, units) 48 # ensure no trailing lone high surrogate 49 if rec and 0xD800 <= rec[-1] <= 0xDBFF: 50 rec.pop() 51 records.append(rec) 52 done += len(rec) 53 rng.shuffle(records) 54 with open(path, "wb") as f: 55 for rec in records: 56 f.write(struct.pack("<I", len(rec))) 57 f.write(st ... [184 chars truncated]

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/verify/verify.c"}

1 // verify.c — exhaustive correctness gate for utf16-transcode. 2 // 1. every single code unit 3 // 2. all pairs from a boundary-stratified sample x sample (16.7M), 4 // plus ALL surrogate x surrogate pairs (2^20) exactly 5 // 3. every code unit at positions 0..3 inside valid padding 6 // 4. 200k seeded random strings across regimes with injected lone surrogates 7 #include <stdint.h> 8 #include <stddef.h> 9 #include <stdio.h> 10 #include <stdlib.h> 11 #include <string.h> 12 #include <pthread.h> 13 #include <stdatomic.h> 14 15 size_t utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out); 16 size_t ref_utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out); 17 18 #define INVALID ((size_t)-1) 19 20 static atomic_ullong n_cases; 21 static atomic_int failed; 22 static pthread_mutex_t report_mu = PTHREAD_MUTEX_INITIALIZER; 23 24 static void fail_report(const uint16_t *in, size_t n, const char *stage) { 25 pthread_mutex_lock(&report_mu); 26 if (!atomic_exchange(&failed, 1)) { 27 fprintf(stderr, "MISMATCH (%s) on %zu units:", stage, n); 28 for (size_t i = 0; i < n && i < 24; i++) fprintf(stderr, " %04x", in[i]); 29 fprintf(stderr, "\n"); 30 } 31 pthread_mutex_unlock(&report_mu); 32 } 33 34 static int check(const uint16_t *in, size_t n, uint8_t *bs, uint8_t *br, const char *stage) { 35 memset(bs, 0xAA, 3 * n + 8); 36 memset(br, 0x55, 3 * n + 8); 37 size_t rs = utf16_to_utf8(in, n, bs); 38 size_t rr = ref_utf16_to_utf8(in, n, br); 39 atomic_fetch_add_explicit(&n_cases, 1, memory_order_relaxed); 40 if (rs != rr || (rr != INVALID && memcmp(bs, br, rr) != 0)) { 41 fail_report(in, n, stage); 42 return 0; 43 } 44 return 1; 45 } 46 47 // boundary-stratified sample of code units: all class edges + strided interior 48 static uint16_t sample[4096]; 49 static size_t n_sample; 50 51 static void build_sample(void) { 52 size_t k = 0; 53 // all boundaries +-2 54 static const uint32_t EDGE[] = {0x0000,0x007F,0x0080,0x07FF,0x0800, 55 0xD7FF,0xD800,0xDBFF,0xDC00,0xDFFF,0xE000,0xFFFF}; 56 for (size_t e = 0; e < sizeof(EDGE)/sizeof(EDGE[0]); e++) 57 for (int d = -2; d <= 2; d++) { 58 int64_t v = (int64_t)EDGE[e] + d; 59 if (v >= 0 && v <= 0xFFFF) sample[k++] = (uint16_t)v; 60 } 61 // strided interior coverage 62 for (uint32_t v = 0; v <= 0xFFFF && k < 4096; v += 17) sample[k++] = (uint16_t)v; 63 n_sample = ... [3959 chars truncated]

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/verify/reference.c"}

1 // reference.c — oracle for utf16-transcode. Defines the semantics. 2 #include <stdint.h> 3 #include <stddef.h> 4 5 #define INVALID ((size_t)-1) 6 7 size_t ref_utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out) { 8 size_t o = 0, i = 0; 9 while (i < n) { 10 uint32_t cu = in[i]; 11 uint32_t cp; 12 if (cu >= 0xD800 && cu <= 0xDBFF) { 13 if (i + 1 >= n) return INVALID; 14 uint32_t lo = in[i + 1]; 15 if (!(lo >= 0xDC00 && lo <= 0xDFFF)) return INVALID; 16 cp = 0x10000u + ((cu - 0xD800u) * 0x400u) + (lo - 0xDC00u); 17 i += 2; 18 } else if (cu >= 0xDC00 && cu <= 0xDFFF) { 19 return INVALID; 20 } else { 21 cp = cu; 22 i += 1; 23 } 24 if (cp <= 0x7F) { 25 out[o++] = (uint8_t)cp; 26 } else if (cp <= 0x7FF) { 27 out[o++] = (uint8_t)(0xC0u | (cp >> 6)); 28 out[o++] = (uint8_t)(0x80u | (cp & 0x3Fu)); 29 } else if (cp <= 0xFFFF) { 30 out[o++] = (uint8_t)(0xE0u | (cp >> 12)); 31 out[o++] = (uint8_t)(0x80u | ((cp >> 6) & 0x3Fu)); 32 out[o++] = (uint8_t)(0x80u | (cp & 0x3Fu)); 33 } else { 34 out[o++] = (uint8_t)(0xF0u | (cp >> 18)); 35 out[o++] = (uint8_t)(0x80u | ((cp >> 12) & 0x3Fu)); 36 out[o++] = (uint8_t)(0x80u | ((cp >> 6) & 0x3Fu)); 37 out[o++] = (uint8_t)(0x80u | (cp & 0x3Fu)); 38 } 39 } 40 return o; 41 } 42

{"command": "./grade 2>&1 | tail -20", "description": "Run baseline grade"}

build 0.3s verify 2.5s PASS measure 0.4s 78,505,521 instructions (given: 78,505,521) SCORE +0.0000 (1.000x)

{"command": "grep -o -m1 -E 'avx2|avx512f|bmi2|sse4_2|popcnt|avx512bw|avx512vl' /proc/cpuinfo | sort -u | tr '\\n' ' '; echo; echo \"---\"; cc --version | head -1; echo \"---nproc---\"; nproc", "description": "Check CPU SIMD features"}

avx2 bmi2 popcnt sse4_2 --- cc (GCC) 15.2.1 20260209 ---nproc--- 8

{"command": "cat .build/given_cost_7.json && echo && echo \"---corpus units---\" && python3 -c \"\nimport struct\nd=open('.build/corpus_7.bin','rb').read()\noff=0; units=0; recs=0\nimport collections\nwhile off+4<=len(d):\n cnt=struct.unpack_from('<I',d,off)[0]; off+=4\n units+=cnt; recs+=1\n off+=2*cnt\nprint('records',recs,'units',units)\nprint('given instr/unit', 78505521/units)\n\"", "description": "Count corpus units"}

{"cost": 78316682} ---corpus units--- records 583 units 1003060 given instr/unit 78.26602695751002

{"command": "cat .build/callgrind.runner_given.out", "description": "View given callgrind output"}

# callgrind format version: 1 creator: callgrind-3.25.1 pid: 3032849 cmd: /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/.build/runner_given /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/.build/corpus_5737.bin part: 1 desc: I1 cache: desc: D1 cache: desc: LL cache: desc: Timerange: Basic block 0 - 2976966 desc: Trigger: Program termination positions: line events: Ir summary: 15700637 ob=(6) /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/.build/runner_given fl=(7) /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/verify/runner.c fn=(4012) main cfi=(8) /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/verify/given.c cfn=(4578) given_utf16_to_utf8 calls=584 11 30 15700637 fl=(8) fn=(4578) 11 2336 -1 584 +1 3504 +1 1752 +1 1168 -1 1207179 +1 804786 -2 402623 +3 805246 -3 805246 +27 460 -29 354 +6 747966 +1 137116 +1 137116 -1 274232 +1 137116 -1 137116 +1 274232 -6 1121949 +1 1647120 +1 1098080 -2 175411 +3 350822 -3 350822 +27 1062 -20 710601 +1 184442 +1 184442 +1 184442 -2 184442 +1 184442 +1 184442 -2 184442 +1 184442 -1 184442 +1 368884 +1 553326 +1 104850 +2 157275 +1 52425 +1 157275 +2 52425 +1 52425 +3 52425 -4 104850 +3 52425 -2 52425 +1 52425 +1 52425 -2 157275 +1 52425 -1 629100 fl=(6) ??? fn=(3954) (below main) cob=(2) /usr/lib/libc.so.6 cfi=(2) ??? cfn=(3956) (below main) calls=1 0 0 15700637 ob=(1) /usr/lib/ld-linux-x86-64.so.2 fl=(1) ??? fn=(0) 0x000000000001ec00 cob=(6) cfi=(6) cfn=(3954) calls=1 0 0 15700637 ob=(2) fl=(2) fn=(3956) cfn=(3998) 0x0000000000027640 calls=1 0 0 15700637 fn=(3998) cob=(6) cfi=(7) cfn=(4012) calls=1 16 0 15700637 totals: 15700637

{"command": "./grade --seed 7 2>&1 | tail -5", "description": "Baseline grade seed 7"}

build 0.2s verify 2.3s PASS measure 0.2s 78,316,682 instructions (given: 78,316,682) SCORE +0.0000 (1.000x)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "content": "// solve.c \u2014 optimized utf16_to_utf8 (UTF-16LE -> UTF-8).\n// AVX2 ASCII fast path + tight scalar fallback.\n#include <stdint.h>\n#include <stddef.h>\n#include <immintrin.h>\n\n#define INVALID ((size_t)-1)\n\n__attribute__((target(\"avx2\")))\nsize_t utf16_to_utf8(const uint16_t *in, size_t n, uint8_t *out) {\n size_t i = 0, o = 0;\n const __m256i ascii_mask = _mm256_set1_epi16((short)0xFF80);\n\n while (i + 16 <= n) {\n __m256i v = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v, ascii_mask)) {\n // all 16 code units are ASCII: pack to 16 bytes.\n __m256i packed = _mm256_packus_epi16(v, v);\n packed = _mm256_permute4x64_epi64(packed, 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16;\n i += 16;\n continue;\n }\n // Non-ASCII in this block: process the 16 units scalar.\n size_t stop = i + 16;\n while (i < stop) {\n uint32_t c = in[i];\n if (c < 0x80) {\n out[o++] = (uint8_t)c;\n i++;\n } else if (c < 0x800) {\n out[o++] = (uint8_t)(0xC0 | (c >> 6));\n out[o++] = (uint8_t)(0x80 | (c & 0x3F));\n i++;\n } else if (c < 0xD800 || c >= 0xE000) {\n out[o++ ... [1976 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -5", "description": "Grade v1 ASCII fast path"}

build 1.1s verify 3.0s PASS measure 0.1s 61,113,766 instructions (given: 78,316,682) SCORE +0.3578 (1.281x)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "content": "// solve.c \u2014 optimized utf16_to_utf8 (UTF-16LE -> UTF-8).\n// AVX2 ASCII fast path + scalar fallback with wide (single-store) encoding.\n//\n// Output capacity is guaranteed >= 3*n+4, and total output is always <= 3*n,\n// so writing up to 4 bytes per step (advancing by the true length) never\n// exceeds the buffer.\n#include <stdint.h>\n#include <stddef.h>\n#include <string.h>\n#include <immintrin.h>\n\n#define INVALID ((size_t)-1)\n\n// Encode one unit at in[i] into out+o. Advances i and o. On invalid input\n// (lone/broken surrogate) executes `return INVALID;`.\n#define STEP() \\\n do { \\\n uint32_t c = in[i]; \\\n if (c < 0x80) { \\\n out[o] = (uint8_t)c; \\\n o += 1; i += 1; \\\n } else if (c < 0x800) { \\\n uint16_t e = (uint16_t)((0xC0 | (c >> 6)) | \\\n ((0x80 | (c & 0x3F)) << 8)); \\\n memcpy(out + o, &e, 2); ... [2653 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v2 wide-store scalar"}

build 1.0s verify 3.1s PASS measure 0.2s 57,481,059 instructions (given: 78,316,682) SCORE +0.4462 (1.362x)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "content": "// solve.c \u2014 optimized utf16_to_utf8 (UTF-16LE -> UTF-8).\n//\n// Strategy, per 16-unit block:\n// * all ASCII -> AVX2 pack 16 units to 16 bytes\n// * no surrogates -> vectorized 1/2/3-byte conversion (four 4-unit groups,\n// each compacted with a pshufb lookup table)\n// * has a surrogate -> scalar (handles pairs + rejects lone surrogates)\n// A scalar tail finishes the last <16 units of each record.\n//\n// Output capacity is guaranteed >= 3*n+4 and total output <= 3*n, so the wide\n// (over-writing) stores below stay in-bounds; see the per-store notes.\n#include <stdint.h>\n#include <stddef.h>\n#include <string.h>\n#include <immintrin.h>\n\n#define INVALID ((size_t)-1)\n\n// pshufb compaction table for a 4-unit BMP group.\n// Index = (mask of units needing >=2 bytes) << 4 | (mask of units needing 3).\n// g_shuf[idx] maps the fixed 4-bytes-per-lane source down to packed UTF-8.\nstatic uint8_t g_shuf[256][16];\nstatic uint8_t g_len[256];\n\n__attribute__((constructor)) static void init_tables(void) {\n for (int idx = 0; idx < 256; idx++) {\n int m2 = idx >> 4, m3 = idx & 0xF;\n int outpos = 0;\n for (int j = 0; j < 4; j++) {\n int len = 1 + ((m2 >> j) & 1) + ((m3 >> j) & 1);\n for (int k = 0; k < len; k++)\n g_shuf[idx][outpos++] = (uint8_t)(4 * j + k);\n }\n ... [6018 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -5", "description": "Grade v3 vectorized BMP"}

build 1.3s verify 3.2s PASS measure 0.1s 38,058,950 instructions (given: 78,316,682) SCORE +1.0411 (2.058x)

{"command": "cat > /tmp/prof.c << 'EOF'\n#include <stdint.h>\n#include <stddef.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\n// Count how units are distributed across paths for the given corpus.\nint main(int argc,char**argv){\n FILE*f=fopen(argv[1],\"rb\"); fseek(f,0,SEEK_END); long sz=ftell(f); fseek(f,0,SEEK_SET);\n uint8_t*d=malloc(sz); fread(d,1,sz,f); fclose(f);\n size_t off=0;\n unsigned long ascii16=0, gen16=0, surr16=0, tail=0, total=0;\n unsigned long u_ascii=0,u_2=0,u_3=0,u_4=0;\n while(off+4<=(size_t)sz){\n uint32_t cnt; memcpy(&cnt,d+off,4); off+=4;\n const uint16_t*in=(const uint16_t*)(d+off); off+=2ull*cnt;\n size_t n=cnt, i=0;\n // classify units\n for(size_t k=0;k<n;k++){uint32_t c=in[k]; if(c<0x80)u_ascii++; else if(c<0x800)u_2++; else if(c<0xD800||c>=0xE000)u_3++; else {u_4++;k++;}}\n while(i+16<=n){\n int allascii=1,anysurr=0;\n for(int j=0;j<16;j++){uint32_t c=in[i+j]; if(c>=0x80)allascii=0; if(c>=0xD800&&c<0xE000)anysurr=1;}\n if(allascii){ascii16+=16;i+=16;}\n else if(!anysurr){gen16+=16;i+=16;}\n else{surr16+=16;i+=16;} // approx (scalar may cross)\n }\n tail+=(n-i);\n total+=n;\n }\n printf(\"total units %lu\\n\",total);\n printf(\"ascii16 %lu (%.1f%%)\\n\",ascii16,100.0*ascii16/total);\n printf(\"gen16 %lu (%.1f%%)\\n\",gen16,100.0*gen16/total);\n printf(\"surr16 %lu (%.1f%%)\\n\",surr16,100.0*surr16/total);\n printf(\"tail %lu (%.1f%%)\\n\",tail,100.0*tail/tota ... [432 chars truncated]

total units 1003060 ascii16 422240 (42.1%) gen16 428784 (42.7%) surr16 147760 (14.7%) tail 4276 (0.4%) --- unit classes --- u_ascii 579358 (57.8%) u_2byte 134857 (13.4%) u_3byte 184489 (18.4%) u_pairs 52178 (10.4% units)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "static uint8_t g_shuf[256][16];\nstatic uint8_t g_len[256];\n\n__attribute__((constructor)) static void init_tables(void) {\n for (int idx = 0; idx < 256; idx++) {\n int m2 = idx >> 4, m3 = idx & 0xF;\n int outpos = 0;\n for (int j = 0; j < 4; j++) {\n int len = 1 + ((m2 >> j) & 1) + ((m3 >> j) & 1);\n for (int k = 0; k < len; k++)\n g_shuf[idx][outpos++] = (uint8_t)(4 * j + k);\n }\n g_len[idx] = (uint8_t)outpos;\n for (; outpos < 16; outpos++)\n g_shuf[idx][outpos] = 0x80; // pshufb -> 0\n }\n}", "new_string": "static uint8_t g_shuf[256][16];\nstatic uint8_t g_len[256];\n\n// pshufb compaction table for an 8-unit group where every unit is 1 or 2 bytes\n// (all < 0x800). Index = 8-bit mask, bit j set if unit j is a single ASCII\n// byte. Source layout is 2 bytes/lane: [lead, cont].\nstatic uint8_t g_shuf2[256][16];\nstatic uint8_t g_len2[256];\n\n__attribute__((constructor)) static void init_tables(void) {\n for (int idx = 0; idx < 256; idx++) {\n int m2 = idx >> 4, m3 = idx & 0xF;\n int outpos = 0;\n for (int j = 0; j < 4; j++) {\n int len = 1 + ((m2 >> j) & 1) + ((m3 >> j) & 1);\n for (int k = 0; k < len; k++)\n g_shuf[idx][outpos++] = (uint8_t)(4 * j + k);\n }\n g_len[idx] = (uint ... [581 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// Encode one unit at in[i] into out+o (advances i, o). On invalid input runs", "new_string": "// Convert 8 units, all < 0x800 (1 or 2 bytes each), to UTF-8 at dst.\n// Returns bytes written (<= 16). Stores 16 bytes.\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv8_2(__m128i w, uint8_t *dst) {\n __m128i two_lead = _mm_or_si128(_mm_srli_epi16(w, 6), _mm_set1_epi16(0x00C0));\n __m128i mask1 = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n __m128i lead = _mm_blendv_epi8(two_lead, w, mask1); // ASCII -> raw byte\n __m128i cont = _mm_or_si128(_mm_and_si128(w, _mm_set1_epi16(0x003F)),\n _mm_set1_epi16(0x0080));\n __m128i word = _mm_or_si128(lead, _mm_slli_epi16(cont, 8));\n\n int idx = _mm_movemask_epi8(_mm_packs_epi16(mask1, mask1)) & 0xFF;\n __m128i packed = _mm_shuffle_epi8(word, _mm_loadu_si128((const __m128i *)g_shuf2[idx]));\n _mm_storeu_si128((__m128i *)dst, packed);\n return g_len2[idx];\n}\n\n// Encode one unit at in[i] into out+o (advances i, o). On invalid input runs"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m256i is_surr = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), surr_tag);\n if (_mm256_testz_si256(is_surr, is_surr)) {\n // no surrogates: vectorized 1/2/3-byte conversion of all 16 units.\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n o += conv4(_mm_cvtepu16_epi32(lo), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o);\n o += conv4(_mm_cvtepu16_epi32(hi), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o);\n i += 16;\n continue;\n }", "new_string": " __m256i is_surr = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), surr_tag);\n if (_mm256_testz_si256(is_surr, is_surr)) {\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n if (_mm256_testz_si256(v, _mm256_set1_epi16((short)0xF800))) {\n // all < 0x800: cheaper 8-wide 1/2-byte path.\n o += conv8_2(lo, out + o);\n o += conv8_2(hi, out + o);\n } else {\n // 1/2/3-byte conversion, four 4-unit groups.\n o += conv4(_mm_cvtepu16_epi32(lo), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), o ... [224 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v4 with 2-byte tier"}

build 1.2s verify 3.2s PASS measure 0.1s 32,381,646 instructions (given: 78,316,682) SCORE +1.2741 (2.419x)

{"command": "cat > /tmp/prof2.c << 'EOF'\n#include <stdint.h>\n#include <stddef.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\nint main(int argc,char**argv){\n FILE*f=fopen(argv[1],\"rb\"); fseek(f,0,SEEK_END); long sz=ftell(f); fseek(f,0,SEEK_SET);\n uint8_t*d=malloc(sz); fread(d,1,sz,f); fclose(f);\n size_t off=0;\n unsigned long ascii16=0, two16=0, three16=0, surr16=0, tail=0, total=0;\n while(off+4<=(size_t)sz){\n uint32_t cnt; memcpy(&cnt,d+off,4); off+=4;\n const uint16_t*in=(const uint16_t*)(d+off); off+=2ull*cnt;\n size_t n=cnt, i=0;\n while(i+16<=n){\n int allascii=1,anysurr=0,all2=1;\n for(int j=0;j<16;j++){uint32_t c=in[i+j]; if(c>=0x80)allascii=0; if(c>=0x800)all2=0; if(c>=0xD800&&c<0xE000)anysurr=1;}\n if(allascii)ascii16+=16;\n else if(anysurr)surr16+=16;\n else if(all2)two16+=16;\n else three16+=16;\n i+=16;\n }\n tail+=(n-i); total+=n;\n }\n printf(\"total %lu\\n\",total);\n printf(\"ascii16 %.1f%% two16 %.1f%% three16 %.1f%% surr16 %.1f%% tail %.1f%%\\n\",\n 100.0*ascii16/total,100.0*two16/total,100.0*three16/total,100.0*surr16/total,100.0*tail/total);\n return 0;\n}\nEOF\ncc -O2 /tmp/prof2.c -o /tmp/prof2 && /tmp/prof2 .build/corpus_7.bin", "description": "Profile refined tier distribution"}

total 1003060 ascii16 42.1% two16 22.8% three16 19.9% surr16 14.7% tail 0.4%

{"command": "cat > /tmp/prof3.c << 'EOF'\n#include <stdint.h>\n#include <stddef.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\nint main(int argc,char**argv){\n FILE*f=fopen(argv[1],\"rb\"); fseek(f,0,SEEK_END); long sz=ftell(f); fseek(f,0,SEEK_SET);\n uint8_t*d=malloc(sz); fread(d,1,sz,f); fclose(f);\n size_t off=0;\n unsigned long three_pure=0, three_mixed=0, surr_units=0, surr_ascii=0, surr_pairunits=0;\n while(off+4<=(size_t)sz){\n uint32_t cnt; memcpy(&cnt,d+off,4); off+=4;\n const uint16_t*in=(const uint16_t*)(d+off); off+=2ull*cnt;\n size_t n=cnt, i=0;\n while(i+16<=n){\n int allascii=1,anysurr=0,all2=1,all3=1;\n for(int j=0;j<16;j++){uint32_t c=in[i+j]; if(c>=0x80)allascii=0; if(c>=0x800)all2=0; if(c<0x800)all3=0; if(c>=0xD800&&c<0xE000)anysurr=1;}\n if(!allascii&&!anysurr&&!all2){ if(all3)three_pure+=16; else three_mixed+=16; }\n if(anysurr){ surr_units+=16; for(int j=0;j<16;j++){uint32_t c=in[i+j]; if(c<0x80)surr_ascii++; else if(c>=0xD800&&c<0xDC00)surr_pairunits+=2;} }\n i+=16;\n }\n }\n printf(\"three_pure %lu three_mixed %lu\\n\",three_pure,three_mixed);\n printf(\"surr_units %lu surr_ascii %lu surr_pairunits(approx) %lu\\n\",surr_units,surr_ascii,surr_pairunits);\n return 0;\n}\nEOF\ncc -O2 /tmp/prof3.c -o /tmp/prof3 && /tmp/prof3 .build/corpus_7.bin", "description": "Profile block purity"}

three_pure 128800 three_mixed 70816 surr_units 147760 surr_ascii 43835 surr_pairunits(approx) 103956

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// Encode one unit at in[i] into out+o (advances i, o). On invalid input runs\n// `return INVALID;`. Writes up to 4 bytes; advancing by the true length.", "new_string": "// Convert 8 units, all in [0x800,0xFFFF] and non-surrogate (exactly 3 bytes\n// each), to 24 UTF-8 bytes at dst. Fixed layout: no table lookup. Stores 28 B.\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline void conv8_3(__m128i w8, uint8_t *dst) {\n __m256i c = _mm256_cvtepu16_epi32(w8);\n __m256i b0 = _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_set1_epi32(0xE0));\n __m256i b1 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(c, 6),\n _mm256_set1_epi32(0x3F)), _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(c, _mm256_set1_epi32(0x3F)),\n _mm256_set1_epi32(0x80));\n __m256i src = _mm256_or_si256(b0, _mm256_or_si256(_mm256_slli_epi32(b1, 8),\n _mm256_slli_epi32(b2, 16)));\n const __m256i sh = _mm256_setr_epi8(\n 0,1,2, 4,5,6, 8,9,10, 12,13,14, -1,-1,-1,-1,\n 0,1,2, 4,5,6, 8,9,10, 12,13,14, -1,-1,-1,-1);\n __m256i packed = _mm256_shuffle_epi8(src, sh);\n _mm_storeu_si128((__m128i *)dst, _mm256_castsi256_si128(packed));\n _mm_storeu_si128((__m128i *)(dst + 12), _mm256_extracti128_si256(packed, 1));\n}\n\n// Encode one unit at in[i] into out+ ... [117 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(v, _mm256_set1_epi16((short)0xF800))) {\n // all < 0x800: cheaper 8-wide 1/2-byte path.\n o += conv8_2(lo, out + o);\n o += conv8_2(hi, out + o);\n } else {\n // 1/2/3-byte conversion, four 4-unit groups.\n o += conv4(_mm_cvtepu16_epi32(lo), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o);\n o += conv4(_mm_cvtepu16_epi32(hi), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o);\n }", "new_string": " if (_mm256_testz_si256(v, _mm256_set1_epi16((short)0xF800))) {\n // all < 0x800: cheaper 8-wide 1/2-byte path.\n o += conv8_2(lo, out + o);\n o += conv8_2(hi, out + o);\n } else if (_mm256_testz_si256(\n _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits2),\n _mm256_setzero_si256()),\n _mm256_set1_epi8(-1))) {\n // all >= 0x800 (and non-surrogate): fixed 3-byte path.\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {\n // mixed 1/2/3-byte conversion, four 4-unit groups.\n ... [292 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " } else if (_mm256_testz_si256(\n _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits2),\n _mm256_setzero_si256()),\n _mm256_set1_epi8(-1))) {\n // all >= 0x800 (and non-surrogate): fixed 3-byte path.\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {", "new_string": " } else if (({\n __m256i small = _mm256_cmpeq_epi16(\n _mm256_and_si256(v, surr_bits), _mm256_setzero_si256());\n _mm256_testz_si256(small, small);\n })) {\n // all >= 0x800 (and non-surrogate): fixed 3-byte path.\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v5 pure3 path"}

build 1.3s verify 3.3s PASS measure 0.1s 28,190,318 instructions (given: 78,316,682) SCORE +1.4741 (2.778x)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "content": "// solve.c \u2014 optimized utf16_to_utf8 (UTF-16LE -> UTF-8).\n//\n// Per 16-unit block:\n// all ASCII -> AVX2 pack 16 units -> 16 bytes\n// no surrogate, all<0x800 -> two 8-wide 1/2-byte groups (pshufb table)\n// no surrogate, all>=0x800 -> two 8-wide fixed 3-byte groups (const shuffle)\n// no surrogate, mixed -> four 4-wide 1/2/3-byte groups (pshufb table)\n// has surrogate -> 8-wide ASCII+pair path when clean, else scalar\n// A scalar tail finishes each record's last <16 units and any non-clean case.\n//\n// Capacity is guaranteed >= 3*n+4 and total output <= 3*n; the wide stores\n// below may over-write a few trailing bytes but stay in-bounds because every\n// SIMD store happens only while >= 8 (usually >= 16) input units remain, which\n// reserves >= 28 (resp. 52) bytes of headroom past the current write offset.\n#include <stdint.h>\n#include <stddef.h>\n#include <string.h>\n#include <immintrin.h>\n\n#define INVALID ((size_t)-1)\n\n// 4-unit BMP compaction: idx = (>=2-byte mask)<<4 | (3-byte mask); 4 bytes/lane.\nstatic uint8_t g_shuf[256][16];\nstatic uint8_t g_len[256];\n// 8-unit all-<0x800 compaction: idx = single-byte(ASCII) mask; 2 bytes/lane.\nstatic uint8_t g_shuf2[256][16];\nstatic uint8_t g_len2[256];\n// 4-unit surrogate-block compaction: idx = (high mask)<<4 | (ASCII mask);\n// 4 bytes/lane; ASCII->1 byte, high->4 bytes, low->0 ... [11782 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -5", "description": "Grade v6 with surrogate SIMD"}

build 1.4s verify 3.5s PASS measure 0.1s 28,248,091 instructions (given: 78,316,682) SCORE +1.4712 (2.772x)

{"command": "cat > /tmp/profs.c << 'EOF'\n#include <stdint.h>\n#include <stddef.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\n#include <immintrin.h>\n// Replicate surr-branch decision to count SIMD-success vs scalar-step.\nint main(int argc,char**argv){\n FILE*f=fopen(argv[1],\"rb\"); fseek(f,0,SEEK_END); long sz=ftell(f); fseek(f,0,SEEK_SET);\n uint8_t*d=malloc(sz); fread(d,1,sz,f); fclose(f);\n size_t off=0;\n unsigned long simd8=0, scalarstep=0, surr_units=0;\n while(off+4<=(size_t)sz){\n uint32_t cnt; memcpy(&cnt,d+off,4); off+=4;\n const uint16_t*in=(const uint16_t*)(d+off); off+=2ull*cnt;\n size_t n=cnt, i=0;\n while(i+16<=n){\n int anysurr=0,allascii=1;\n for(int j=0;j<16;j++){uint32_t c=in[i+j]; if(c>=0x80)allascii=0; if(c>=0xD800&&c<0xE000)anysurr=1;}\n if(!anysurr){ i+=16; continue; }\n // surr branch\n surr_units+=16;\n size_t blockend=i+16;\n while(i<blockend){\n int ok=0;\n if(i+8<=n){\n // clean check: only ascii/high/low, valid pairing, no hi@7\n int mhi=0,mlo=0,bad=0;\n for(int j=0;j<8;j++){uint32_t c=in[i+j];\n int h=(c>=0xD800&&c<0xDC00), l=(c>=0xDC00&&c<0xE000), a=(c<0x80);\n if(!(h||l||a))bad=1;\n if(h)mhi|=1<<j; if(l)mlo|=1<<j;}\n if(!bad && !(mhi&0x80) && mlo==(mhi<<1)) ok=1;\n }\n if(ok){simd8++; i+=8;}\n else{scalarstep++; uint32_t c=in[i]; if(c>=0xD800&&c<0xDC00)i+=2; else i+=1; ... [296 chars truncated]

surr_units 141888 simd8_calls 17705 (=141640 units) scalar_steps 4446

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\npython3 -c \"\nimport struct,random\nrng=random.Random(1)\ndef write(path, genunit, pair=False):\n with open(path,'wb') as f:\n total=0\n while total<1000000:\n m=rng.randrange(500,3000)\n units=[]\n while len(units)<m:\n if pair:\n cp=rng.randrange(0x10000,0x110000)-0x10000\n units.append(0xD800+(cp>>10)); units.append(0xDC00+(cp&0x3FF))\n else:\n units.append(genunit())\n units=units[:m]\n if units and 0xD800<=units[-1]<=0xDBFF: units.pop()\n f.write(struct.pack('<I',len(units))); f.write(struct.pack('<%dH'%len(units),*units))\n total+=len(units)\nwrite('/tmp/ascii.bin', lambda: rng.randrange(0x20,0x7F))\nwrite('/tmp/latin.bin', lambda: rng.randrange(0x80,0x800))\nwrite('/tmp/cjk.bin', lambda: rng.randrange(0x4E00,0x9FFF))\nwrite('/tmp/emoji.bin', None, pair=True)\nprint('done')\n\"\nfor c in ascii latin cjk emoji; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out .build/runner /tmp/$c.bin >/dev/null 2>&1\n printf \"%-6s \" $c; grep '^summary:' /tmp/cg_$c.out\ndone", "description": "Measure per-regime cost"}

done ascii summary: 872417 latin summary: 4580628 cjk summary: 4369538 emoji summary: 14746316

{"command": "/tmp/profs /tmp/emoji.bin", "description": "Check surr firing on pure emoji"}

surr_units 996464 simd8_calls 124558 (=996464 units) scalar_steps 0

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 4-unit surrogate-block compaction: idx = (high mask)<<4 | (ASCII mask);\n// 4 bytes/lane; ASCII->1 byte, high->4 bytes, low->0 bytes.\nstatic uint8_t g_shufS[256][16];\nstatic uint8_t g_lenS[256];\n\n__attribute__((constructor)) static void init_tables(void) {", "new_string": "__attribute__((constructor)) static void init_tables(void) {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " for (int idx = 0; idx < 256; idx++) {\n int mh = idx >> 4, ma = idx & 0xF, outpos = 0;\n for (int j = 0; j < 4; j++) {\n if ((ma >> j) & 1) g_shufS[idx][outpos++] = (uint8_t)(4 * j);\n else if ((mh >> j) & 1)\n for (int k = 0; k < 4; k++) g_shufS[idx][outpos++] = (uint8_t)(4 * j + k);\n }\n g_lenS[idx] = (uint8_t)outpos;\n for (; outpos < 16; outpos++) g_shufS[idx][outpos] = 0x80;\n }\n}", "new_string": "}"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 8 units that are only ASCII + valid high/low surrogate pairs (no high at\n// position 7). Returns bytes written (<=16), or -1 if the block is not clean.\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline int try_conv8_surr(const uint16_t *p, uint8_t *dst) {\n __m128i w = _mm_loadu_si128((const __m128i *)p);\n __m128i fc00 = _mm_set1_epi16((short)0xFC00);\n __m128i hi = _mm_cmpeq_epi16(_mm_and_si128(w, fc00), _mm_set1_epi16((short)0xD800));\n __m128i lo = _mm_cmpeq_epi16(_mm_and_si128(w, fc00), _mm_set1_epi16((short)0xDC00));\n __m128i ascii = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n __m128i allowed = _mm_or_si128(ascii, _mm_or_si128(hi, lo));\n if (!_mm_test_all_ones(allowed)) return -1; // BMP multibyte present\n int mhi = _mm_movemask_epi8(_mm_packs_epi16(hi, hi)) & 0xFF;\n int mlo = _mm_movemask_epi8(_mm_packs_epi16(lo, lo)) & 0xFF;\n if ((mhi & 0x80) || mlo != (mhi << 1)) return -1; // hi@7 or bad pairing\n int masc = _mm_movemask_epi8(_mm_packs_epi16(ascii, ascii)) & 0xFF;\n\n __m256i c32 = _mm256_cvtepu16_epi32(w);\n __m256i lonext = _mm256_cvtepu16_epi32(_mm_bsrli_si128(w, 2));\n __m256i m3ff = _mm256_set1_epi32(0x3FF), m3f = _mm256_set1_epi32(0x3F);\n __m256i cp = _mm256_add_epi32(_mm256_se ... [2597 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " // surrogate present: try 8-wide clean path, else scalar.\n size_t blockend = i + 16;\n while (i < blockend) {\n if (i + 8 <= n) {\n int r = try_conv8_surr(in + i, out + o);\n if (r >= 0) { o += (size_t)r; i += 8; continue; }\n }\n STEP();\n }", "new_string": " // surrogate present: at each pair boundary, blast runs of pairs with a\n // fixed 4-byte expansion; ASCII/other units fall through to scalar.\n size_t blockend = i + 16;\n while (i < blockend) {\n uint32_t c = in[i];\n if (c >= 0xD800 && c < 0xDC00 && i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n __m128i fc = _mm_set1_epi16((short)0xFC00);\n __m128i hh = _mm_cmpeq_epi16(_mm_and_si128(w, fc), _mm_set1_epi16((short)0xD800));\n __m128i ll = _mm_cmpeq_epi16(_mm_and_si128(w, fc), _mm_set1_epi16((short)0xDC00));\n int mhi = _mm_movemask_epi8(_mm_packs_epi16(hh, hh)) & 0xFF;\n int mlo = _mm_movemask_epi8(_mm_packs_epi16(ll, ll)) & 0xFF;\n if (mhi == 0x55 && mlo == 0xAA) { // 4 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n ... [276 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v7 pair-run blaster"}

build 1.7s verify 7.2s PASS measure 0.1s 25,395,599 instructions (given: 78,316,682) SCORE +1.6247 (3.084x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v7\nfor c in ascii latin cjk emoji; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v7 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-6s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit (%d)\\n\", $2/1000000, $2}'\ndone", "description": "Re-measure per-regime v7"}

ascii 0.87/unit (871267) latin 4.58/unit (4579482) cjk 4.37/unit (4368392) emoji 8.70/unit (8704093)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " return _mm_or_si128(_mm_or_si128(b0, _mm_slli_epi32(b1, 8)),\n _mm_or_si128(_mm_slli_epi32(b2, 16), _mm_slli_epi32(b3, 24)));\n}", "new_string": " return _mm_or_si128(_mm_or_si128(b0, _mm_slli_epi32(b1, 8)),\n _mm_or_si128(_mm_slli_epi32(b2, 16), _mm_slli_epi32(b3, 24)));\n}\n\n// 8 consecutive pairs (16 units) as 8 dwords -> 32 UTF-8 bytes.\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline __m256i enc_pairs_word256(__m256i w) {\n __m256i m3ff = _mm256_set1_epi32(0x3FF), m3f = _mm256_set1_epi32(0x3F);\n __m256i hh = _mm256_and_si256(w, m3ff);\n __m256i ll = _mm256_and_si256(_mm256_srli_epi32(w, 16), m3ff);\n __m256i cp = _mm256_add_epi32(_mm256_set1_epi32(0x10000),\n _mm256_add_epi32(_mm256_slli_epi32(hh, 10), ll));\n __m256i b0 = _mm256_or_si256(_mm256_srli_epi32(cp, 18), _mm256_set1_epi32(0xF0));\n __m256i b1 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(cp, 12), m3f), _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(cp, 6), m3f), _mm256_set1_epi32(0x80));\n __m256i b3 = _mm256_or_si256(_mm256_and_si256(cp, m3f), _mm256_set1_epi32(0x80));\n return _mm256_or_si256(_mm256_or_si256(b0, _mm256_slli_epi32(b1, 8)),\n _mm256_or_si256(_mm256_slli_epi32(b2, 16), _mm256_sll ... [23 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " // surrogate present: at each pair boundary, blast runs of pairs with a\n // fixed 4-byte expansion; ASCII/other units fall through to scalar.\n size_t blockend = i + 16;", "new_string": " // surrogate present. Fast path: the whole block is 8 clean pairs.\n __m256i fc16 = _mm256_set1_epi16((short)0xFC00);\n __m256i hi16 = _mm256_cmpeq_epi16(_mm256_and_si256(v, fc16), surr_tag);\n __m256i lo16 = _mm256_cmpeq_epi16(_mm256_and_si256(v, fc16),\n _mm256_set1_epi16((short)0xDC00));\n __m256i d = _mm256_or_si256(_mm256_xor_si256(hi16, _mm256_set1_epi32(0x0000FFFF)),\n _mm256_xor_si256(lo16, _mm256_set1_epi32((int)0xFFFF0000)));\n if (_mm256_testz_si256(d, d)) {\n _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v));\n o += 32; i += 16;\n continue;\n }\n // Otherwise blast pair runs at each boundary; other units go scalar.\n size_t blockend = i + 16;"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v8 8-pair fast path"}

build 1.6s verify 3.8s PASS measure 0.1s 25,366,507 instructions (given: 78,316,682) SCORE +1.6264 (3.087x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v8\nfor c in emoji; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v8 /tmp/$c.bin >/dev/null 2>&1\n printf \"pure %-6s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\n# Now simulate the REAL emoji regime (40% ascii runs 1-8, 60% pairs 1-6)\npython3 -c \"\nimport struct,random\nrng=random.Random(5)\nwith open('/tmp/emojireal.bin','wb') as f:\n total=0\n while total<1000000:\n m=rng.randrange(500,3000); u=[]\n while len(u)<m:\n if rng.random()<0.4:\n u.extend(rng.randrange(0x20,0x7F) for _ in range(rng.randrange(1,8)))\n else:\n for _ in range(rng.randrange(1,6)):\n cp=rng.randrange(0x10000,0x110000)-0x10000; u.append(0xD800+(cp>>10)); u.append(0xDC00+(cp&0x3FF))\n u=u[:m]\n if u and 0xD800<=u[-1]<=0xDBFF: u.pop()\n f.write(struct.pack('<I',len(u))); f.write(struct.pack('<%dH'%len(u),*u)); total+=len(u)\n\"\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_er.out /tmp/runner_v8 /tmp/emojireal.bin >/dev/null 2>&1\nprintf \"real emoji \"; grep '^summary:' /tmp/cg_er.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'", "description": "Measure pure vs realistic emoji"}

pure emoji 4.22/unit real emoji 12.26/unit

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_real.out /tmp/runner_v8 .build/corpus_7.bin >/dev/null 2>&1\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_real.out 2>/dev/null | grep -A80 'solve.c' | head -110", "description": "Line-level annotation on real corpus"}

1,947,746 (42.62%) submission/solve.c:utf16_to_utf8 [/tmp/runner_v8] 1,501,304 (32.85%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h:utf16_to_utf8 719,436 (15.74%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h:utf16_to_utf8 293,314 ( 6.42%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avxintrin.h:utf16_to_utf8 46,350 ( 1.01%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/tmmintrin.h:utf16_to_utf8 44,260 ( 0.97%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/xmmintrin.h:utf16_to_utf8 -------------------------------------------------------------------------------- -- Auto-annotated source: submission/solve.c -------------------------------------------------------------------------------- Ir -- line 55 ---------------------------------------- . __m128i three_b1 = _mm_or_si128(_mm_and_si128(c6, m3f), _mm_set1_epi32(0x80)); . __m128i b2 = _mm_or_si128(_mm_and_si128(c, m3f), _mm_set1_epi32(0x80)); . __m128i two_b0 = _mm_or_si128(c6, _mm_set1_epi32(0xC0)); . __m128i m2 = _mm_cmpgt_epi32(c, _mm_set1_epi32(0x7F)); . __m128i m3 = _mm_cmpgt_epi32(c, _mm_set1_epi32(0x7FF)); . __m128i b0 = _mm_blendv_epi8(_mm_blendv_epi8(c, two_b0, m2), three_b0, m3); . __m128i b1 = _mm_blendv_epi8(b2, three_b1, m3); . __m128i src = _mm_or_si128(b0, _mm_or_si128(_mm_slli_epi32(b1, 8), _mm_slli_epi32(b2, 16))); 44,260 ( 0.97%) int idx = (_mm_movemask_ps(_mm_castsi128_ps(m2)) << 4) | _mm_movemask_ps(_mm_castsi128_ps(m3)); . _mm_storeu_si128((__m128i *)dst, 17,704 ( 0.39%) _mm_shuffle_epi8(src, _mm_loadu_si128((const __m128i *)g_shuf[idx]))); 22,130 ( 0.48%) return g_len[idx]; . } . . // 8 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=16). . __attribute__((always_inline, target("avx2"))) . static inline size_t conv8_2(__m128i w, uint8_t *dst) { . __m128i two_lead = _mm_or_si128(_mm_srli_epi16(w, 6), _mm_set1_epi16(0x00C0)); . __m128i mask1 = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), . _mm_setzero_si128()); . __m128i lead = _mm_blendv_epi8(two_lead, w, mask1); . __m128i cont = ... [3873 chars truncated]

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_real.out 2>/dev/null | grep -A200 'Auto-annotated source' | sed -n '95,200p'", "description": "See surrogate branch annotation"}

-- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/tmmintrin.h -------------------------------------------------------------------------------- Ir -- line 130 ---------------------------------------- . _mm_mulhrs_pi16 (__m64 __X, __m64 __Y) . { . return (__m64) __builtin_ia32_pmulhrsw ((__v4hi)__X, (__v4hi)__Y); . } . . extern __inline __m128i __attribute__((__gnu_inline__, __always_inline__, __artificial__)) . _mm_shuffle_epi8 (__m128i __X, __m128i __Y) . { 46,350 ( 1.01%) return (__m128i) __builtin_ia32_pshufb128 ((__v16qi)__X, (__v16qi)__Y); . } . . extern __inline __m64 __attribute__((__gnu_inline__, __always_inline__, __artificial__)) . _mm_shuffle_pi8 (__m64 __X, __m64 __Y) . { . return (__m64) __builtin_ia32_pshufb ((__v8qi)__X, (__v8qi)__Y); . } . -- line 146 ---------------------------------------- -------------------------------------------------------------------------------- -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h -------------------------------------------------------------------------------- Ir -- line 92 ---------------------------------------- . { . return (__m256i)__builtin_ia32_packusdw256 ((__v8si)__A, (__v8si)__B); . } . . extern __inline __m256i . __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) . _mm256_packus_epi16 (__m256i __A, __m256i __B) . { 26,428 ( 0.58%) return (__m256i)__builtin_ia32_packuswb256 ((__v16hi)__A, (__v16hi)__B); . } . . extern __inline __m256i . __attribute__ ((__gnu_inline__, __always_inline__, __artificial__)) . _mm256_add_epi8 (__m256i __A, __m256i __B) . { . return (__m256i) ((__v32qu)__A + (__v32qu)__B); . } -- line 108 ---------------------------------------- -- line 113 ---------------------------------------- . { . return (__m256i) ((__v16hu)__A + (__v16hu)__B); . } . . extern __inline __m256i ... [2400 chars truncated]

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\npython3 -c \"\nimport struct,random\nrng=random.Random(9)\ndef gen(path,regime):\n with open(path,'wb') as f:\n total=0\n while total<1000000:\n m=rng.randrange(500,3000); u=[]\n while len(u)<m:\n if regime=='latin':\n if rng.random()<0.5: u.extend(rng.randrange(0x20,0x7F) for _ in range(rng.randrange(2,10)))\n else: u.extend(rng.randrange(0x80,0x800) for _ in range(rng.randrange(2,12)))\n else: # cjk\n if rng.random()<0.25: u.extend(rng.randrange(0x20,0x7F) for _ in range(rng.randrange(1,6)))\n else: u.extend(rng.randrange(0x4E00,0x9FFF) for _ in range(rng.randrange(4,20)))\n u=u[:m]\n f.write(struct.pack('<I',len(u))); f.write(struct.pack('<%dH'%len(u),*u)); total+=len(u)\ngen('/tmp/latinreal.bin','latin'); gen('/tmp/cjkreal.bin','cjk')\n\"\nfor c in latinreal cjkreal; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v8 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\necho \"--- weighted estimate (real, per unit) ---\"\npython3 -c \"\n# per-unit costs\na,l,c,e=0.87,None,None,12.26\nimport re\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\nl=s('/tmp/cg_latinreal.out'); c=s('/tmp/ ... [476 chars truncated]

latinreal 4.26/unit cjkreal 6.49/unit --- weighted estimate (real, per unit) --- latin 4.26 cjk 6.49 emoji 12.26 weighted real total ~4551913 real instr, contributions: ascii 348000 (8%) latin 1066057 (23%) cjk 1298856 (29%) emoji 1839000 (40%)

{"command": "cat > /tmp/profe.c << 'EOF'\n#include <stdint.h>\n#include <stddef.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\nint main(int argc,char**argv){\n FILE*f=fopen(argv[1],\"rb\"); fseek(f,0,SEEK_END); long sz=ftell(f); fseek(f,0,SEEK_SET);\n uint8_t*d=malloc(sz); fread(d,1,sz,f); fclose(f);\n size_t off=0;\n unsigned long p8=0,p4=0,p2=0,sc_pair=0,sc_ascii=0,sc_other=0;\n while(off+4<=(size_t)sz){\n uint32_t cnt; memcpy(&cnt,d+off,4); off+=4;\n const uint16_t*in=(const uint16_t*)(d+off); off+=2ull*cnt;\n size_t n=cnt,i=0;\n while(i+16<=n){\n int anysurr=0,allascii=1;\n for(int j=0;j<16;j++){uint32_t c=in[i+j]; if(c>=0x80)allascii=0; if(c>=0xD800&&c<0xE000)anysurr=1;}\n if(allascii){i+=16;continue;}\n if(!anysurr){i+=16;continue;}\n // 8-pair check\n int is8=1; for(int j=0;j<16;j++){uint32_t c=in[i+j]; int h=(c>=0xD800&&c<0xDC00),l=(c>=0xDC00&&c<0xE000); if((j%2==0&&!h)||(j%2==1&&!l))is8=0;}\n if(is8){p8++;i+=16;continue;}\n size_t be=i+16;\n while(i<be){\n uint32_t c=in[i];\n if(c>=0xD800&&c<0xDC00&&i+8<=n){\n int mhi=0,mlo=0; for(int j=0;j<8;j++){uint32_t x=in[i+j];if(x>=0xD800&&x<0xDC00)mhi|=1<<j;if(x>=0xDC00&&x<0xE000)mlo|=1<<j;}\n if(mhi==0x55&&mlo==0xAA){p4++;i+=8;continue;}\n if((mhi&0xF)==0x5&&(mlo&0xF)==0xA){p2++;i+=4;continue;}\n }\n if(c>=0xD800&&c<0xDC00){sc_pair++;i+=2;}\n else if(c<0x80){sc_ascii++;i+=1;}\n ... [392 chars truncated]

8pair-blocks 10125 (162000 u) 4pair 49270 (394160 u) 2pair 21324 (85296 u) scalar: pairs 24663 (49326 u) ascii 286282 other 0

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " // Otherwise blast pair runs at each boundary; other units go scalar.\n size_t blockend = i + 16;\n while (i < blockend) {\n uint32_t c = in[i];\n if (c >= 0xD800 && c < 0xDC00 && i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n __m128i fc = _mm_set1_epi16((short)0xFC00);\n __m128i hh = _mm_cmpeq_epi16(_mm_and_si128(w, fc), _mm_set1_epi16((short)0xD800));\n __m128i ll = _mm_cmpeq_epi16(_mm_and_si128(w, fc), _mm_set1_epi16((short)0xDC00));\n int mhi = _mm_movemask_epi8(_mm_packs_epi16(hh, hh)) & 0xFF;\n int mlo = _mm_movemask_epi8(_mm_packs_epi16(ll, ll)) & 0xFF;\n if (mhi == 0x55 && mlo == 0xAA) { // 4 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mhi & 0xF) == 0x5 && (mlo & 0xF) == 0xA) { // 2 pairs\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n }\n STEP();\n }", "new_string": " // Otherwise: vectorize ASCII runs and pair runs; rest goes scalar.\n size_t blockend = i + 16;\n while (i < blockend) ... [1864 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v9 ascii-run in surr"}

build 1.1s verify 4.3s PASS measure 0.2s 23,216,464 instructions (given: 78,316,682) SCORE +1.7542 (3.373x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v9\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v9 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contributions: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure regimes v9"}

emojireal 9.45/unit latinreal 4.21/unit cjkreal 6.50/unit ascii 0.87/unit contributions: ascii 8% latin 26% cjk 32% emoji 34%

{"command": "cat > /tmp/profc.c << 'EOF'\n#include <stdint.h>\n#include <stddef.h>\n#include <stdio.h>\n#include <stdlib.h>\n#include <string.h>\nint main(int argc,char**argv){\n FILE*f=fopen(argv[1],\"rb\"); fseek(f,0,SEEK_END); long sz=ftell(f); fseek(f,0,SEEK_SET);\n uint8_t*d=malloc(sz); fread(d,1,sz,f); fclose(f);\n size_t off=0; unsigned long ascii=0,two=0,three=0,mixed=0,tail=0,tot=0;\n while(off+4<=(size_t)sz){\n uint32_t cnt; memcpy(&cnt,d+off,4); off+=4;\n const uint16_t*in=(const uint16_t*)(d+off); off+=2ull*cnt;\n size_t n=cnt,i=0;\n while(i+16<=n){\n int aa=1,a2=1,a3=1,sur=0;\n for(int j=0;j<16;j++){uint32_t c=in[i+j];if(c>=0x80)aa=0;if(c>=0x800)a2=0;if(c<0x800)a3=0;if(c>=0xD800&&c<0xE000)sur=1;}\n if(aa)ascii+=16; else if(sur){} else if(a2)two+=16; else if(a3)three+=16; else mixed+=16;\n i+=16;\n }\n tail+=n-i; tot+=n;\n }\n printf(\"ascii %.1f two %.1f three(pure) %.1f MIXED %.1f tail %.1f (of %lu)\\n\",\n 100.*ascii/tot,100.*two/tot,100.*three/tot,100.*mixed/tot,100.*tail/tot,tot);\n return 0;\n}\nEOF\ncc -O2 /tmp/profc.c -o /tmp/profc && printf \"cjkreal: \" && /tmp/profc /tmp/cjkreal.bin && printf \"corpus7: \" && /tmp/profc /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/.build/corpus_7.bin", "description": "Profile cjk tier split"}

cjkreal: ascii 0.0 two 0.0 three(pure) 63.9 MIXED 35.6 tail 0.4 (of 1000804) corpus7: ascii 42.1 two 22.8 three(pure) 12.8 MIXED 7.1 tail 0.4 (of 1003060)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {\n o += conv4(_mm_cvtepu16_epi32(lo), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o);\n o += conv4(_mm_cvtepu16_epi32(hi), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o);\n }\n i += 16;\n continue;", "new_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n continue;\n }\n // mixed 1/2/3-byte (no surrogate): run-based conversion.\n size_t mend = i + 16;\n while (i < mend) {\n uint32_t c = in[i];\n if (i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n if (c < 0x80) {\n __m128i am = _mm_cmpeq_epi16(\n _mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), _mm_setzero_si128());\n int m = _mm_m ... [1573 chars truncated]

<tool_use_error>String to replace not found in file. String: if (_mm256_testz_si256(small, small)) { conv8_3(lo, out + o); o += 24; conv8_3(hi, out + o); o += 24; } else { o += conv4(_mm_cvtepu16_epi32(lo), out + o); o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o); o += conv4(_mm_cvtepu16_epi32(hi), out + o); o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o); } i += 16; continue;</tool_use_error>

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 185, "limit": 45}

185 } else { 186 __m256i small = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), 187 _mm256_setzero_si256()); 188 if (_mm256_testz_si256(small, small)) { 189 conv8_3(lo, out + o); o += 24; 190 conv8_3(hi, out + o); o += 24; 191 } else { 192 o += conv4(_mm_cvtepu16_epi32(lo), out + o); 193 o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o); 194 o += conv4(_mm_cvtepu16_epi32(hi), out + o); 195 o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o); 196 } 197 } 198 i += 16; 199 continue; 200 } 201 // surrogate present. Fast path: the whole block is 8 clean pairs. 202 __m256i fc16 = _mm256_set1_epi16((short)0xFC00); 203 __m256i hi16 = _mm256_cmpeq_epi16(_mm256_and_si256(v, fc16), surr_tag); 204 __m256i lo16 = _mm256_cmpeq_epi16(_mm256_and_si256(v, fc16), 205 _mm256_set1_epi16((short)0xDC00)); 206 __m256i d = _mm256_or_si256(_mm256_xor_si256(hi16, _mm256_set1_epi32(0x0000FFFF)), 207 _mm256_xor_si256(lo16, _mm256_set1_epi32((int)0xFFFF0000))); 208 if (_mm256_testz_si256(d, d)) { 209 _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v)); 210 o += 32; i += 16; 211 continue; 212 } 213 // Otherwise: vectorize ASCII runs and pair runs; rest goes scalar. 214 size_t blockend = i + 16; 215 while (i < blockend) { 216 uint32_t c = in[i]; 217 if (i + 8 <= n) { 218 if (c < 0x80) { 219 // ASCII run: pack the leading consecutive ASCII units. 220 __m128i w = _mm_loadu_si128((const __m128i *)(in + i)); 221 __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), 222 _mm_setzero_si128()); 223 int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF; 224 int k = __builtin_ctz((unsigned)(~m) | 0x100); 225 _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); 226 o += (size_t)k; i += (size_t)k; 227 ... [85 chars truncated]

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {\n o += conv4(_mm_cvtepu16_epi32(lo), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o);\n o += conv4(_mm_cvtepu16_epi32(hi), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o);\n }\n }\n i += 16;\n continue;\n }", "new_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n continue;\n }\n // mixed 1/2/3-byte (no surrogate): run-based conversion.\n size_t mend = i + 16;\n while (i < mend) {\n uint32_t c = in[i];\n if (i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n if (c < 0x80) {\n __m128i am = _mm_cmpeq_epi16(\n _mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), _mm_setzero_si128());\n ... [1662 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 170, "limit": 65}

170 while (i + 16 <= n) { 171 __m256i v = _mm256_loadu_si256((const __m256i *)(in + i)); 172 if (_mm256_testz_si256(v, ascii_mask)) { 173 __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8); 174 _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed)); 175 o += 16; i += 16; 176 continue; 177 } 178 __m256i is_surr = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), surr_tag); 179 if (_mm256_testz_si256(is_surr, is_surr)) { 180 __m128i lo = _mm256_castsi256_si128(v); 181 __m128i hi = _mm256_extracti128_si256(v, 1); 182 if (_mm256_testz_si256(v, surr_bits)) { 183 o += conv8_2(lo, out + o); 184 o += conv8_2(hi, out + o); 185 } else { 186 __m256i small = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), 187 _mm256_setzero_si256()); 188 if (_mm256_testz_si256(small, small)) { 189 conv8_3(lo, out + o); o += 24; 190 conv8_3(hi, out + o); o += 24; 191 i += 16; 192 continue; 193 } 194 // mixed 1/2/3-byte (no surrogate): run-based conversion. 195 size_t mend = i + 16; 196 while (i < mend) { 197 uint32_t c = in[i]; 198 if (i + 8 <= n) { 199 __m128i w = _mm_loadu_si128((const __m128i *)(in + i)); 200 if (c < 0x80) { 201 __m128i am = _mm_cmpeq_epi16( 202 _mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), _mm_setzero_si128()); 203 int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF; 204 int k = __builtin_ctz((unsigned)(~m) | 0x100); 205 _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); 206 o += (size_t)k; i += (size_t)k; 207 continue; 208 } 209 __m128i t = _mm_and_si128(w, _mm_set1_epi16((short)0xF800)); 210 if (_mm_testz_si128(t, t)) { // all 8 < 0x800 211 o += conv8_2(w, out + o); i += 8; continue; 212 } 213 ... [1172 chars truncated]

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v10 mixed run loop"}

build 1.1s verify 2.2s PASS measure 0.1s 23,399,480 instructions (given: 78,316,682) SCORE +1.7428 (3.347x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v10\nfor c in cjkreal latinreal emojireal; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v10 /tmp/$c.bin >/dev/null 2>&1\n printf \"v10 %-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone", "description": "Per-regime v10"}

v10 cjkreal 6.90/unit v10 latinreal 4.04/unit v10 emojireal 9.41/unit

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n continue;\n }\n // mixed 1/2/3-byte (no surrogate): run-based conversion.\n size_t mend = i + 16;\n while (i < mend) {\n uint32_t c = in[i];\n if (i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n if (c < 0x80) {\n __m128i am = _mm_cmpeq_epi16(\n _mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), _mm_setzero_si128());\n int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF;\n int k = __builtin_ctz((unsigned)(~m) | 0x100);\n _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w));\n o += (size_t)k; i += (size_t)k;\n continue;\n }\n __m128i t = _mm_and_si128(w, _mm_set1_epi16((short)0xF800));\n if (_mm_testz_si128(t, t)) { // all 8 < 0x800\n o += conv8_2(w, out + o); i += 8; contin ... [1662 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3\necho \"=== disasm conv8_3 + dispatch ===\"\ncc -O2 -std=c17 -g -c submission/solve.c -o /tmp/solve.o 2>/dev/null\nobjdump -d --no-show-raw-insn /tmp/solve.o 2>/dev/null | awk '/<utf16_to_utf8>:/{p=1} p{print} /ret/{if(p)c++} c>0&&p&&/ret/{exit}' | wc -l", "description": "Confirm revert, count asm"}

verify 2.4s PASS measure 0.1s 23,216,464 instructions (given: 78,316,682) SCORE +1.7542 (3.373x) === disasm conv8_3 + dispatch === 124

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v9b\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_ev9.out /tmp/runner_v9b /tmp/emojireal.bin >/dev/null 2>&1\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_ev9.out 2>/dev/null | grep -E 'solve.c:[0-9]|pshufb128|pshufb|packuswb|pmovmskb|packsswb|pcmpeq|_mm_or|_mm_and|storeu|storel' | head -40", "description": "Emoji line annotation v9"}

. _mm_storeu_si128 (__m128i_u *__P, __m128i __B) . _mm_storel_epi64 (__m128i_u *__P, __m128i __B) . _mm_storeu_si64 (void *__P, __m128i __B) . _mm_storel_epi64 ((__m128i_u *)__P, __B); 238,124 ( 2.52%) return (__m128i)__builtin_ia32_packsswb128 ((__v8hi)__A, (__v8hi)__B); 58,228 ( 0.62%) return (__m128i)__builtin_ia32_packuswb128 ((__v8hi)__A, (__v8hi)__B); . _mm_and_si128 (__m128i __A, __m128i __B) . _mm_andnot_si128 (__m128i __A, __m128i __B) . _mm_or_si128 (__m128i __A, __m128i __B) 238,124 ( 2.52%) return __builtin_ia32_pmovmskb128 ((__v16qi)__A); . _mm256_storeu_si256 (__m256i_u *__P, __m256i __A) . _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed)); . _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v)); . __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), . _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); . __m128i hh = _mm_cmpeq_epi16(_mm_and_si128(w, fc), _mm_set1_epi16((short)0xD800)); . __m128i ll = _mm_cmpeq_epi16(_mm_and_si128(w, fc), _mm_set1_epi16((short)0xDC00)); . _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); . _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w)); 833 ( 0.01%) return (__m256i)__builtin_ia32_packuswb256 ((__v16hi)__A, (__v16hi)__B);

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " // surrogate present. Fast path: the whole block is 8 clean pairs.\n __m256i fc16 = _mm256_set1_epi16((short)0xFC00);\n __m256i hi16 = _mm256_cmpeq_epi16(_mm256_and_si256(v, fc16), surr_tag);\n __m256i lo16 = _mm256_cmpeq_epi16(_mm256_and_si256(v, fc16),\n _mm256_set1_epi16((short)0xDC00));\n __m256i d = _mm256_or_si256(_mm256_xor_si256(hi16, _mm256_set1_epi32(0x0000FFFF)),\n _mm256_xor_si256(lo16, _mm256_set1_epi32((int)0xFFFF0000)));\n if (_mm256_testz_si256(d, d)) {\n _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v));\n o += 32; i += 16;\n continue;\n }\n // Otherwise: vectorize ASCII runs and pair runs; rest goes scalar.\n size_t blockend = i + 16;\n while (i < blockend) {\n uint32_t c = in[i];\n if (i + 8 <= n) {\n if (c < 0x80) {\n // ASCII run: pack the leading consecutive ASCII units.\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) ... [3642 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v11 cheap pair detection"}

build 2.1s verify 2.7s PASS measure 0.1s 22,097,531 instructions (given: 78,316,682) SCORE +1.8254 (3.544x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v11\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v11 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure regimes v11"}

emojireal 8.17/unit latinreal 4.21/unit cjkreal 6.47/unit ascii 0.87/unit contrib: ascii 9% latin 27% cjk 33% emoji 31%

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_cjkp.out /tmp/runner_v11 /tmp/cjk.bin >/dev/null 2>&1\necho \"=== pure cjk total ===\"; grep '^summary:' /tmp/cg_cjkp.out\necho \"=== top intrinsics ===\"\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_cjkp.out 2>/dev/null | grep -E '\\([0-9]+\\.[0-9]+%\\)' | grep -iE 'builtin_ia32|__v|return|_mm|epi|si256|si128' | sort -t'(' -k2 -rn | head -20", "description": "Annotate pure cjk"}

=== pure cjk total === summary: 4434197 === top intrinsics === 997,872 (22.50%) return (__m256i) ((__v4du)__A | (__v4du)__B); 498,936 (11.25%) return (__m256i) ((__v4du)__A & (__v4du)__B);

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_cjkp.out 2>/dev/null | grep -B1 -E '^\\s*[0-9,]+ \\([0-9]+\\.[0-9]+%\\)' | grep -iE 'builtin_ia32_(psrl|pslli|pshufb|pcmp|pmovmsk|pand|por|packs|packus|permq|extract|cvt)|__v[0-9]|__A [|&^]|storeu|storel|loadu|while|if ' | head -30\necho \"--- raw solve.c lines ---\"\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_cjkp.out 2>/dev/null | grep -E 'solve.c' | grep -E '[0-9],[0-9]|[0-9]+ \\(' | head", "description": "Fuller cjk intrinsic breakdown"}

498,936 (11.25%) return (__m256i) ((__v4du)__A & (__v4du)__B); 997,872 (22.50%) return (__m256i) ((__v4du)__A | (__v4du)__B); --- raw solve.c lines --- 998,855 (22.53%) submission/solve.c:utf16_to_utf8 [/tmp/runner_v11]

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "static inline void conv8_3(__m128i w8, uint8_t *dst) {\n __m256i c = _mm256_cvtepu16_epi32(w8);\n __m256i b0 = _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_set1_epi32(0xE0));\n __m256i b1 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(c, 6),\n _mm256_set1_epi32(0x3F)), _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(c, _mm256_set1_epi32(0x3F)),\n _mm256_set1_epi32(0x80));\n __m256i src = _mm256_or_si256(b0, _mm256_or_si256(_mm256_slli_epi32(b1, 8),\n _mm256_slli_epi32(b2, 16)));", "new_string": "static inline void conv8_3(__m128i w8, uint8_t *dst) {\n __m256i c = _mm256_cvtepu16_epi32(w8);\n __m256i m3f = _mm256_set1_epi32(0x3F);\n __m256i raw1 = _mm256_and_si256(_mm256_srli_epi32(c, 6), m3f);\n __m256i raw2 = _mm256_and_si256(c, m3f);\n __m256i src = _mm256_or_si256(\n _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_slli_epi32(raw1, 8)),\n _mm256_or_si256(_mm256_slli_epi32(raw2, 16), _mm256_set1_epi32(0x008080E0)));"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m128i hh = _mm_and_si128(w, m3ff);\n __m128i ll = _mm_and_si128(_mm_srli_epi32(w, 16), m3ff);\n __m128i cp = _mm_add_epi32(_mm_set1_epi32(0x10000),\n _mm_add_epi32(_mm_slli_epi32(hh, 10), ll));\n __m128i b0 = _mm_or_si128(_mm_srli_epi32(cp, 18), _mm_set1_epi32(0xF0));\n __m128i b1 = _mm_or_si128(_mm_and_si128(_mm_srli_epi32(cp, 12), m3f), _mm_set1_epi32(0x80));\n __m128i b2 = _mm_or_si128(_mm_and_si128(_mm_srli_epi32(cp, 6), m3f), _mm_set1_epi32(0x80));\n __m128i b3 = _mm_or_si128(_mm_and_si128(cp, m3f), _mm_set1_epi32(0x80));\n return _mm_or_si128(_mm_or_si128(b0, _mm_slli_epi32(b1, 8)),\n _mm_or_si128(_mm_slli_epi32(b2, 16), _mm_slli_epi32(b3, 24)));", "new_string": " __m128i hh = _mm_and_si128(w, m3ff);\n __m128i ll = _mm_and_si128(_mm_srli_epi32(w, 16), m3ff);\n __m128i cp = _mm_add_epi32(_mm_set1_epi32(0x10000),\n _mm_add_epi32(_mm_slli_epi32(hh, 10), ll));\n __m128i raw1 = _mm_and_si128(_mm_srli_epi32(cp, 12), m3f);\n __m128i raw2 = _mm_and_si128(_mm_srli_epi32(cp, 6), m3f);\n __m128i raw3 = _mm_and_si128(cp, m3f);\n return _mm_or_si128(\n _mm_or_si128(_mm_srli_epi32(cp, 18), _mm_slli_epi32(raw1, 8)),\n _mm_or_si128(_mm_or_si128(_mm_slli_epi32(raw2, 16), _mm_slli_epi32(raw3, 24)),\n _mm_set1_epi32((int)0x8 ... [13 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m256i hh = _mm256_and_si256(w, m3ff);\n __m256i ll = _mm256_and_si256(_mm256_srli_epi32(w, 16), m3ff);\n __m256i cp = _mm256_add_epi32(_mm256_set1_epi32(0x10000),\n _mm256_add_epi32(_mm256_slli_epi32(hh, 10), ll));\n __m256i b0 = _mm256_or_si256(_mm256_srli_epi32(cp, 18), _mm256_set1_epi32(0xF0));\n __m256i b1 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(cp, 12), m3f), _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(cp, 6), m3f), _mm256_set1_epi32(0x80));\n __m256i b3 = _mm256_or_si256(_mm256_and_si256(cp, m3f), _mm256_set1_epi32(0x80));\n return _mm256_or_si256(_mm256_or_si256(b0, _mm256_slli_epi32(b1, 8)),\n _mm256_or_si256(_mm256_slli_epi32(b2, 16), _mm256_slli_epi32(b3, 24)));", "new_string": " __m256i hh = _mm256_and_si256(w, m3ff);\n __m256i ll = _mm256_and_si256(_mm256_srli_epi32(w, 16), m3ff);\n __m256i cp = _mm256_add_epi32(_mm256_set1_epi32(0x10000),\n _mm256_add_epi32(_mm256_slli_epi32(hh, 10), ll));\n __m256i raw1 = _mm256_and_si256(_mm256_srli_epi32(cp, 12), m3f);\n __m256i raw2 = _mm256_and_si256(_mm256_srli_epi32(cp, 6), m3f);\n __m256i raw3 = _mm256_and_si256(cp, m3f);\n return _mm256_or_si256(\n _mm256_or_si256(_mm256_srli_epi32(cp, 18), _mm256_slli_epi32(raw1, 8)),\n ... [163 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v12 folded markers"}

build 0.9s verify 2.4s PASS measure 0.1s 21,289,042 instructions (given: 78,316,682) SCORE +1.8792 (3.679x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m256i is_surr = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), surr_tag);\n if (_mm256_testz_si256(is_surr, is_surr)) {\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n if (_mm256_testz_si256(v, surr_bits)) {\n o += conv8_2(lo, out + o);\n o += conv8_2(hi, out + o);\n } else {\n __m256i small = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits),\n _mm256_setzero_si256());\n if (_mm256_testz_si256(small, small)) {", "new_string": " __m256i t = _mm256_and_si256(v, surr_bits);\n __m256i is_surr = _mm256_cmpeq_epi16(t, surr_tag);\n if (_mm256_testz_si256(is_surr, is_surr)) {\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n if (_mm256_testz_si256(t, t)) {\n o += conv8_2(lo, out + o);\n o += conv8_2(hi, out + o);\n } else {\n __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256());\n if (_mm256_testz_si256(small, small)) {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v13 dispatch reuse"}

build 2.1s verify 2.7s PASS measure 0.1s 21,280,992 instructions (given: 78,316,682) SCORE +1.8798 (3.680x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v13\nfor c in emojireal latinreal cjkreal ascii latin cjk emoji; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v13 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure all regimes v13"}

emojireal 7.70/unit latinreal 4.21/unit cjkreal 6.19/unit ascii 0.87/unit latin 4.52/unit cjk 4.00/unit emoji 3.54/unit contrib: ascii 9% latin 28% cjk 33% emoji 30%

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_ev13.out /tmp/runner_v13 /tmp/emojireal.bin >/dev/null 2>&1\necho \"emoji total:\"; grep summary: /tmp/cg_ev13.out\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_ev13.out 2>/dev/null | grep -E '[0-9,]+ \\([0-9]+\\.[0-9]+%\\)' | grep -iE 'builtin_ia32|__v|storel|storeu|memcpy|while|if |c = in|STEP|ctz' | head -25", "description": "Annotate emojireal v13"}

emoji total: summary: 7696538 933,410 (12.13%) STEP();

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncallgrind_annotate --auto=yes --inclusive=no --threshold=99 /tmp/cg_ev13.out 2>/dev/null | grep -E '^\\s*[0-9,]+ \\([0-9.]+%\\)' | head -30", "description": "Top cost lines emojireal"}

7,696,538 (100.0%) PROGRAM TOTALS 4,020,212 (52.23%) submission/solve.c:utf16_to_utf8 [/tmp/runner_v13] 2,460,536 (31.97%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h:utf16_to_utf8 895,605 (11.64%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h:utf16_to_utf8 933,410 (12.13%) STEP(); 7,696,538 (100.0%) events annotated

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_ev13.out 2>/dev/null | awk '/Auto-annotated source: submission\\/solve.c/{f=1} f' | grep -E '\\([0-9.]+%\\)' | head -40", "description": "Solve.c annotated lines emojireal"}

933,410 (12.13%) STEP(); 7,696,538 (100.0%) events annotated

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (mm == 0xF) { // 4 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mm & 3) == 3) { // 2 pairs\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n }\n STEP();", "new_string": " if (mm == 0xF) { // 4 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mm & 3) == 3) { // 2 pairs\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n if (mm & 1) { // 1 pair\n _mm_storeu_si32(out + o, enc_pairs_word(w));\n o += 4; i += 2; continue;\n }\n }\n STEP();"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v14 single-pair fast path"}

build 1.3s verify 2.4s PASS measure 0.1s 21,180,437 instructions (given: 78,316,682) SCORE +1.8866 (3.698x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncc -O2 -std=c17 -march=x86-64-v2 -mavx2 -mbmi2 -g -c submission/solve.c -o /tmp/solve.o 2>/dev/null\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p' | grep -cE 'vpbroadcast|vmovdqa.*rip|set1|vpcmpeq|vpand|vpor'\necho \"--- total insns in function ---\"\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p&&/^$/{if(seen)exit} p{print; seen=1}' | grep -cE '^\\s+[0-9a-f]+:'\necho \"--- broadcasts (constant materialization) in function ---\"\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p&&/^$/{if(seen)exit} p{print; seen=1}' | grep -cE 'vpbroadcast|broadcast'", "description": "Check constant materialization"}

119 --- total insns in function --- 616 --- broadcasts (constant materialization) in function --- 13

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 8 units all in [0x800,0xFFFF] non-surrogate (3 bytes each) -> 24 bytes.", "new_string": "// 16 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=32).\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv16_2(__m256i v, uint8_t *dst) {\n __m256i two_lead = _mm256_or_si256(_mm256_srli_epi16(v, 6), _mm256_set1_epi16(0x00C0));\n __m256i mask1 = _mm256_cmpeq_epi16(_mm256_and_si256(v, _mm256_set1_epi16((short)0xFF80)),\n _mm256_setzero_si256());\n __m256i lead = _mm256_blendv_epi8(two_lead, v, mask1);\n __m256i cont = _mm256_or_si256(_mm256_and_si256(v, _mm256_set1_epi16(0x003F)),\n _mm256_set1_epi16(0x0080));\n __m256i word = _mm256_or_si256(lead, _mm256_slli_epi16(cont, 8));\n int mm = _mm256_movemask_epi8(_mm256_packs_epi16(mask1, mask1));\n int idx0 = mm & 0xFF, idx1 = (mm >> 16) & 0xFF;\n __m256i shuf = _mm256_inserti128_si256(\n _mm256_castsi128_si256(_mm_loadu_si128((const __m128i *)g_shuf2[idx0])),\n _mm_loadu_si128((const __m128i *)g_shuf2[idx1]), 1);\n __m256i packed = _mm256_shuffle_epi8(word, shuf);\n size_t len0 = g_len2[idx0];\n _mm_storeu_si128((__m128i *)dst, _mm256_castsi256_si128(packed));\n _mm_storeu_si128((__m128i *)(dst + len0), _mm256_extracti128_si256(packed, 1));\n return len ... [100 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(t, t)) {\n o += conv8_2(lo, out + o);\n o += conv8_2(hi, out + o);\n } else {", "new_string": " if (_mm256_testz_si256(t, t)) {\n o += conv16_2(v, out + o);\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v15 conv16_2"}

build 1.8s verify 3.2s PASS measure 0.1s 20,347,161 instructions (given: 78,316,682) SCORE +1.9445 (3.849x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v15\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v15 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure regimes v15"}

emojireal 7.47/unit latinreal 3.58/unit cjkreal 6.19/unit ascii 0.87/unit contrib: ascii 10% latin 25% cjk 34% emoji 31%

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nfor s in 1 42 12345; do ./grade --seed $s 2>&1 | grep SCORE | sed \"s/^/seed $s: /\"; done", "description": "Grade multiple seeds"}

seed 1: SCORE +1.9361 (3.827x) seed 42: SCORE +1.9362 (3.827x) seed 12345: SCORE +1.9407 (3.839x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 8 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=16).\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv8_2(__m128i w, uint8_t *dst) {", "new_string": "// 8 BMP units (no surrogate) in 32-bit lanes -> UTF-8 (1/2/3 bytes). Returns\n// bytes (<=24). Shares arithmetic across both 4-unit compaction groups.\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv8_mixed(__m256i c, uint8_t *dst) {\n __m256i m3f = _mm256_set1_epi32(0x3F);\n __m256i c6 = _mm256_srli_epi32(c, 6), c12 = _mm256_srli_epi32(c, 12);\n __m256i three_b0 = _mm256_or_si256(c12, _mm256_set1_epi32(0xE0));\n __m256i three_b1 = _mm256_or_si256(_mm256_and_si256(c6, m3f), _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(c, m3f), _mm256_set1_epi32(0x80));\n __m256i two_b0 = _mm256_or_si256(c6, _mm256_set1_epi32(0xC0));\n __m256i m2 = _mm256_cmpgt_epi32(c, _mm256_set1_epi32(0x7F));\n __m256i m3 = _mm256_cmpgt_epi32(c, _mm256_set1_epi32(0x7FF));\n __m256i b0 = _mm256_blendv_epi8(_mm256_blendv_epi8(c, two_b0, m2), three_b0, m3);\n __m256i b1 = _mm256_blendv_epi8(b2, three_b1, m3);\n __m256i src = _mm256_or_si256(b0, _mm256_or_si256(_mm256_slli_epi32(b1, 8),\n _mm256_slli_epi32(b2, 16)));\n int mm2 = _mm256_movemask_ps(_mm256_castsi256_ps(m2));\n int mm3 ... [778 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " } else {\n o += conv4(_mm_cvtepu16_epi32(lo), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(lo, 8)), out + o);\n o += conv4(_mm_cvtepu16_epi32(hi), out + o);\n o += conv4(_mm_cvtepu16_epi32(_mm_srli_si128(hi, 8)), out + o);\n }", "new_string": " } else {\n o += conv8_mixed(_mm256_cvtepu16_epi32(lo), out + o);\n o += conv8_mixed(_mm256_cvtepu16_epi32(hi), out + o);\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v16 conv8_mixed"}

build 1.2s verify 2.6s PASS measure 0.1s 20,072,953 instructions (given: 78,316,682) SCORE +1.9641 (3.902x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v16\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v16 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v16"}

emojireal 7.48/unit latinreal 3.58/unit cjkreal 5.85/unit ascii 0.88/unit contrib: ascii 10% latin 25% cjk 33% emoji 32%

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_e16.out /tmp/runner_v16 /tmp/emojireal.bin >/dev/null 2>&1\necho \"total:\"; grep summary: /tmp/cg_e16.out\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_e16.out 2>/dev/null | awk '/Auto-annotated source: submission/{f=1} f' | grep -E '\\([0-9.]+%\\)' | head\necho \"--- header split ---\"\ncallgrind_annotate --inclusive=no /tmp/cg_e16.out 2>/dev/null | grep -E 'include|solve.c:utf' | head", "description": "Annotate emoji v16"}

total: summary: 7476923 7,476,923 (100.0%) events annotated --- header split --- 3,231,055 (43.21%) submission/solve.c:utf16_to_utf8 [/tmp/runner_v16] 2,976,320 (39.81%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h:utf16_to_utf8 949,363 (12.70%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h:utf16_to_utf8 230,237 ( 3.08%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avxintrin.h:utf16_to_utf8 89,948 ( 1.20%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/xmmintrin.h:utf16_to_utf8 -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avxintrin.h -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/xmmintrin.h -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_e16.out 2>/dev/null | awk '/annotated source.*emmintrin/{f=1} f&&/\\([0-9.]+%\\)/{print} /annotated source.*avx2/{f=0}' | head -20", "description": "Emoji SSE2 op breakdown"}

749,638 (10.03%) return (__m128i) ((__v2du)__A & (__v2du)__B); 7,476,923 (100.0%) events annotated

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncc -O2 -std=c17 -mavx2 -mbmi2 -g -c submission/solve.c -o /tmp/solve.o 2>/dev/null\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p&&/^$/{exit} p' > /tmp/asm.txt\necho \"total function insns:\"; grep -cE '^\\s+[0-9a-f]+:' /tmp/asm.txt\necho \"--- instruction mix ---\"\ngrep -oE '^\\s+[0-9a-f]+:\\s+[a-z][a-z0-9]+' /tmp/asm.txt | awk '{print $2}' | sort | uniq -c | sort -rn | head -25", "description": "Instruction mix of function"}

total function insns: 572 --- instruction mix --- 54 mov 37 vpor 36 add 30 vpand 28 vpsrld 28 cmp 27 lea 24 vpslld 22 or 21 and 18 shl 16 jmp 14 vmovd 13 vpbroadcastd 12 vmovdqu 12 jae 11 movzbl 10 vmovdqa 10 shr 9 nopl 8 vpaddd 8 ja 7 vpshufb 7 vpcmpeqd 7 vpblendvb

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "__attribute__((always_inline, target(\"avx2\")))\nstatic inline __m128i enc_pairs_word(__m128i w) {\n __m128i m3ff = _mm_set1_epi32(0x3FF), m3f = _mm_set1_epi32(0x3F);\n __m128i hh = _mm_and_si128(w, m3ff);\n __m128i ll = _mm_and_si128(_mm_srli_epi32(w, 16), m3ff);\n __m128i cp = _mm_add_epi32(_mm_set1_epi32(0x10000),\n _mm_add_epi32(_mm_slli_epi32(hh, 10), ll));\n __m128i raw1 = _mm_and_si128(_mm_srli_epi32(cp, 12), m3f);", "new_string": "__attribute__((always_inline, target(\"avx2\")))\nstatic inline __m128i enc_pairs_word(__m128i w) {\n __m128i m3f = _mm_set1_epi32(0x3F);\n // cp = (high<<10) + low - 0x35FDC00 (folds the -0xD800*0x400 - 0xDC00 + 0x10000)\n __m128i cp = _mm_add_epi32(\n _mm_add_epi32(_mm_slli_epi32(_mm_and_si128(w, _mm_set1_epi32(0xFFFF)), 10),\n _mm_srli_epi32(w, 16)),\n _mm_set1_epi32((int)0xFCA02400));\n __m128i raw1 = _mm_and_si128(_mm_srli_epi32(cp, 12), m3f);"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m256i m3ff = _mm256_set1_epi32(0x3FF), m3f = _mm256_set1_epi32(0x3F);\n __m256i hh = _mm256_and_si256(w, m3ff);\n __m256i ll = _mm256_and_si256(_mm256_srli_epi32(w, 16), m3ff);\n __m256i cp = _mm256_add_epi32(_mm256_set1_epi32(0x10000),\n _mm256_add_epi32(_mm256_slli_epi32(hh, 10), ll));\n __m256i raw1 = _mm256_and_si256(_mm256_srli_epi32(cp, 12), m3f);", "new_string": " __m256i m3f = _mm256_set1_epi32(0x3F);\n __m256i cp = _mm256_add_epi32(\n _mm256_add_epi32(_mm256_slli_epi32(_mm256_and_si256(w, _mm256_set1_epi32(0xFFFF)), 10),\n _mm256_srli_epi32(w, 16)),\n _mm256_set1_epi32((int)0xFCA02400));\n __m256i raw1 = _mm256_and_si256(_mm256_srli_epi32(cp, 12), m3f);"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ngrep -n 'conv4\\|conv8_2' submission/solve.c", "description": "Find dead helper references"}

51:static inline size_t conv4(__m128i c, uint8_t *dst) { 101:static inline size_t conv8_2(__m128i w, uint8_t *dst) {

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 49, "limit": 70}

49 // 4 BMP units (no surrogate) in 32-bit lanes -> UTF-8. Returns bytes (<=12). 50 __attribute__((always_inline, target("avx2"))) 51 static inline size_t conv4(__m128i c, uint8_t *dst) { 52 const __m128i m3f = _mm_set1_epi32(0x3F); 53 __m128i c6 = _mm_srli_epi32(c, 6), c12 = _mm_srli_epi32(c, 12); 54 __m128i three_b0 = _mm_or_si128(c12, _mm_set1_epi32(0xE0)); 55 __m128i three_b1 = _mm_or_si128(_mm_and_si128(c6, m3f), _mm_set1_epi32(0x80)); 56 __m128i b2 = _mm_or_si128(_mm_and_si128(c, m3f), _mm_set1_epi32(0x80)); 57 __m128i two_b0 = _mm_or_si128(c6, _mm_set1_epi32(0xC0)); 58 __m128i m2 = _mm_cmpgt_epi32(c, _mm_set1_epi32(0x7F)); 59 __m128i m3 = _mm_cmpgt_epi32(c, _mm_set1_epi32(0x7FF)); 60 __m128i b0 = _mm_blendv_epi8(_mm_blendv_epi8(c, two_b0, m2), three_b0, m3); 61 __m128i b1 = _mm_blendv_epi8(b2, three_b1, m3); 62 __m128i src = _mm_or_si128(b0, _mm_or_si128(_mm_slli_epi32(b1, 8), _mm_slli_epi32(b2, 16))); 63 int idx = (_mm_movemask_ps(_mm_castsi128_ps(m2)) << 4) | _mm_movemask_ps(_mm_castsi128_ps(m3)); 64 _mm_storeu_si128((__m128i *)dst, 65 _mm_shuffle_epi8(src, _mm_loadu_si128((const __m128i *)g_shuf[idx]))); 66 return g_len[idx]; 67 } 68 69 // 8 BMP units (no surrogate) in 32-bit lanes -> UTF-8 (1/2/3 bytes). Returns 70 // bytes (<=24). Shares arithmetic across both 4-unit compaction groups. 71 __attribute__((always_inline, target("avx2"))) 72 static inline size_t conv8_mixed(__m256i c, uint8_t *dst) { 73 __m256i m3f = _mm256_set1_epi32(0x3F); 74 __m256i c6 = _mm256_srli_epi32(c, 6), c12 = _mm256_srli_epi32(c, 12); 75 __m256i three_b0 = _mm256_or_si256(c12, _mm256_set1_epi32(0xE0)); 76 __m256i three_b1 = _mm256_or_si256(_mm256_and_si256(c6, m3f), _mm256_set1_epi32(0x80)); 77 __m256i b2 = _mm256_or_si256(_mm256_and_si256(c, m3f), _mm256_set1_epi32(0x80)); 78 __m256i two_b0 = _mm256_or_si256(c6, _mm256_set1_epi32(0xC0)); 79 __m256i m2 = _mm256_cmpgt_epi32(c, _mm256_set1_epi32(0x7F)); 80 __m256i m3 = _mm256_cmpgt_epi32(c, _mm256_set1_epi32(0x7FF)); 81 __m256i b0 = _mm256_blendv_epi8(_mm256_blendv_epi8(c, two_b0, m2), three_b0, m3); 82 __m256i b1 = _mm256_blendv_epi8(b2, three_b1, m3); 83 __m256i src = _mm256_or_si256(b0, _mm256_or_si256(_mm256_slli_epi32(b1, 8), 84 _mm256_slli_epi32(b2, 16))); 85 int mm2 = _mm256_movemask_ps(_mm256_castsi256_ps(m2)); 86 int mm3 = _mm256_movemask_ps(_mm256_castsi256_ps(m3)); 87 int ... [1838 chars truncated]

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 4 BMP units (no surrogate) in 32-bit lanes -> UTF-8. Returns bytes (<=12).\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv4(__m128i c, uint8_t *dst) {\n const __m128i m3f = _mm_set1_epi32(0x3F);\n __m128i c6 = _mm_srli_epi32(c, 6), c12 = _mm_srli_epi32(c, 12);\n __m128i three_b0 = _mm_or_si128(c12, _mm_set1_epi32(0xE0));\n __m128i three_b1 = _mm_or_si128(_mm_and_si128(c6, m3f), _mm_set1_epi32(0x80));\n __m128i b2 = _mm_or_si128(_mm_and_si128(c, m3f), _mm_set1_epi32(0x80));\n __m128i two_b0 = _mm_or_si128(c6, _mm_set1_epi32(0xC0));\n __m128i m2 = _mm_cmpgt_epi32(c, _mm_set1_epi32(0x7F));\n __m128i m3 = _mm_cmpgt_epi32(c, _mm_set1_epi32(0x7FF));\n __m128i b0 = _mm_blendv_epi8(_mm_blendv_epi8(c, two_b0, m2), three_b0, m3);\n __m128i b1 = _mm_blendv_epi8(b2, three_b1, m3);\n __m128i src = _mm_or_si128(b0, _mm_or_si128(_mm_slli_epi32(b1, 8), _mm_slli_epi32(b2, 16)));\n int idx = (_mm_movemask_ps(_mm_castsi128_ps(m2)) << 4) | _mm_movemask_ps(_mm_castsi128_ps(m3));\n _mm_storeu_si128((__m128i *)dst,\n _mm_shuffle_epi8(src, _mm_loadu_si128((const __m128i *)g_shuf[idx])));\n return g_len[idx];\n}\n\n// 8 BMP units (no surrogate) in 32-bit lanes -> UTF-8 (1/2/3 bytes). Returns", "new_string": "// 8 BMP units (no surrogate) in 32-bit lanes -> UTF-8 (1/2/3 bytes). Returns"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 8 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=16).\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv8_2(__m128i w, uint8_t *dst) {\n __m128i two_lead = _mm_or_si128(_mm_srli_epi16(w, 6), _mm_set1_epi16(0x00C0));\n __m128i mask1 = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n __m128i lead = _mm_blendv_epi8(two_lead, w, mask1);\n __m128i cont = _mm_or_si128(_mm_and_si128(w, _mm_set1_epi16(0x003F)), _mm_set1_epi16(0x0080));\n __m128i word = _mm_or_si128(lead, _mm_slli_epi16(cont, 8));\n int idx = _mm_movemask_epi8(_mm_packs_epi16(mask1, mask1)) & 0xFF;\n _mm_storeu_si128((__m128i *)dst,\n _mm_shuffle_epi8(word, _mm_loadu_si128((const __m128i *)g_shuf2[idx])));\n return g_len2[idx];\n}\n\n// 16 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=32).", "new_string": "// 16 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=32)."}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v17 cleanup + cp reformulation"}

build 1.7s verify 2.6s PASS measure 0.1s 19,960,986 instructions (given: 78,316,682) SCORE +1.9721 (3.923x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncc -O2 -std=c17 -mavx2 -mbmi2 -g -c submission/solve.c -o /tmp/solve.o 2>/dev/null\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p&&/^$/{exit} p' > /tmp/asm.txt\n# find the conv8_3 region: between vpmovzxwd instances\ngrep -n 'vpmovzxwd\\|vpshufb.*ymm\\|vpsrld.*0xc\\|vpslld' /tmp/asm.txt | head -30", "description": "Find conv8_3 asm region"}

196: 32e: vpslld $0xa,%xmm1,%xmm1 201: 346: vpsrld $0xc,%xmm1,%xmm4 204: 353: vpslld $0x18,%xmm5,%xmm5 206: 35c: vpslld $0x10,%xmm0,%xmm0 207: 361: vpslld $0x8,%xmm4,%xmm4 220: 39d: vpslld $0xa,%xmm0,%xmm0 225: 3b5: vpsrld $0xc,%xmm0,%xmm4 228: 3c2: vpslld $0x18,%xmm5,%xmm5 230: 3cb: vpslld $0x10,%xmm1,%xmm1 231: 3d0: vpslld $0x8,%xmm4,%xmm4 244: 40e: vpslld $0xa,%xmm0,%xmm0 249: 426: vpsrld $0xc,%xmm0,%xmm4 252: 433: vpslld $0x18,%xmm5,%xmm5 254: 43c: vpslld $0x10,%xmm1,%xmm1 255: 441: vpslld $0x8,%xmm4,%xmm4 324: 571: vpshufb %ymm4,%ymm0,%ymm0 357: 60c: vpslld $0xa,%ymm0,%ymm0 364: 62c: vpsrld $0xc,%ymm0,%ymm3 366: 635: vpslld $0x18,%ymm4,%ymm4 369: 643: vpslld $0x10,%ymm1,%ymm1 373: 653: vpslld $0x8,%ymm2,%ymm2 390: 6a2: vpmovzxwd %xmm0,%ymm0 391: 6a7: vpmovzxwd %xmm4,%ymm4 392: 6ac: vpsrld $0xc,%ymm0,%ymm7 402: 6df: vpsrld $0xc,%ymm4,%ymm5 408: 6ff: vpslld $0x8,%ymm7,%ymm7 410: 708: vpslld $0x8,%ymm6,%ymm6 413: 715: vpslld $0x10,%ymm2,%ymm2 420: 738: vpshufb %ymm2,%ymm0,%ymm0 423: 74b: vpslld $0x10,%ymm3,%ymm0

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nsed -n '388,440p' /tmp/asm.txt", "description": "conv8_3 x2 region"}

698: vextracti128 $0x1,%ymm0,%xmm0 69e: vpcmpeqw %ymm2,%ymm1,%ymm1 6a2: vpmovzxwd %xmm0,%ymm0 6a7: vpmovzxwd %xmm4,%ymm4 6ac: vpsrld $0xc,%ymm0,%ymm7 6b1: vpsrld $0x6,%ymm0,%ymm15 6b6: vpcmpeqd %ymm14,%ymm14,%ymm14 6bb: vpsrld $0x1a,%ymm14,%ymm2 6c1: vpsrld $0x6,%ymm4,%ymm8 6c6: vmovdqa %ymm7,-0x18(%rsp) 6cc: vptest %ymm1,%ymm1 6d1: vpand %ymm15,%ymm2,%ymm6 6d6: vpand %ymm2,%ymm0,%ymm3 6da: vpand %ymm8,%ymm2,%ymm7 6df: vpsrld $0xc,%ymm4,%ymm5 6e4: vpand %ymm2,%ymm4,%ymm2 6e8: vmovdqa %ymm2,0x8(%rsp) 6ee: jne 804 <utf16_to_utf8+0x804> 6f4: mov $0x8080e0,%eax 6f9: vmovdqa 0x8(%rsp),%ymm2 6ff: vpslld $0x8,%ymm7,%ymm7 704: vmovd %eax,%xmm1 708: vpslld $0x8,%ymm6,%ymm6 70d: mov %rdi,%rax 710: vpbroadcastd %xmm1,%ymm1 715: vpslld $0x10,%ymm2,%ymm2 71a: lea 0x10(%rax),%rdi 71e: vpor %ymm5,%ymm1,%ymm0 722: vpor %ymm7,%ymm2,%ymm2 726: vpor -0x18(%rsp),%ymm1,%ymm1 72c: vpor %ymm2,%ymm0,%ymm0 730: vmovdqa 0x0(%rip),%ymm2 # 738 <utf16_to_utf8+0x738> 738: vpshufb %ymm2,%ymm0,%ymm0 73d: vmovdqu %xmm0,(%r12) 743: vextracti128 $0x1,%ymm0,0xc(%r12) 74b: vpslld $0x10,%ymm3,%ymm0 750: vpor %ymm6,%ymm0,%ymm0 754: vpor %ymm1,%ymm0,%ymm0 758: vpshufb %ymm2,%ymm0,%ymm0 75d: vmovdqu %xmm0,0x18(%r10,%rsi,1) 764: vextracti128 $0x1,%ymm0,0x24(%r10,%rsi,1) 76c: add $0x30,%rsi 770: cmp %rdi,%r8 773: jae 70 <utf16_to_utf8+0x70> 779: jmp 1b0 <utf16_to_utf8+0x1b0> 77e: xchg %ax,%ax 780: cmp $0xdbff,%ecx 786: ja 9e3 <utf16_to_utf8+0x9e3> 78c: lea 0x1(%rax),%rcx 790: cmp %r8,%rcx 793: jae 9e3 <utf16_to_utf8+0x9e3> 799: movzwl 0x2(%r9,%rdi,1),%ecx 79f: lea -0xdc00(%rcx),%edi

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 120, "limit": 22}

120 // high | low<<16), returns the 16 UTF-8 bytes (4 bytes/pair) as a register. 121 __attribute__((always_inline, target("avx2"))) 122 static inline __m128i enc_pairs_word(__m128i w) { 123 __m128i m3f = _mm_set1_epi32(0x3F); 124 // cp = (high<<10) + low - 0x35FDC00 (folds the -0xD800*0x400 - 0xDC00 + 0x10000) 125 __m128i cp = _mm_add_epi32( 126 _mm_add_epi32(_mm_slli_epi32(_mm_and_si128(w, _mm_set1_epi32(0xFFFF)), 10), 127 _mm_srli_epi32(w, 16)), 128 _mm_set1_epi32((int)0xFCA02400)); 129 __m128i raw1 = _mm_and_si128(_mm_srli_epi32(cp, 12), m3f); 130 __m128i raw2 = _mm_and_si128(_mm_srli_epi32(cp, 6), m3f); 131 __m128i raw3 = _mm_and_si128(cp, m3f); 132 return _mm_or_si128( 133 _mm_or_si128(_mm_srli_epi32(cp, 18), _mm_slli_epi32(raw1, 8)), 134 _mm_or_si128(_mm_or_si128(_mm_slli_epi32(raw2, 16), _mm_slli_epi32(raw3, 24)), 135 _mm_set1_epi32((int)0x808080F0))); 136 } 137 138 // 8 consecutive pairs (16 units) as 8 dwords -> 32 UTF-8 bytes. 139 __attribute__((always_inline, target("avx2"))) 140 static inline __m256i enc_pairs_word256(__m256i w) { 141 __m256i m3f = _mm256_set1_epi32(0x3F);

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 155, "limit": 20}

155 // Encode one unit at in[i] into out+o (advances i, o). On invalid input runs 156 // `return INVALID;`. Writes up to 4 bytes; advances by the true length. 157 #define STEP() \ 158 do { \ 159 uint32_t c = in[i]; \ 160 if (c < 0x80) { \ 161 out[o] = (uint8_t)c; o += 1; i += 1; \ 162 } else if (c < 0x800) { \ 163 uint16_t e = (uint16_t)((0xC0 | (c >> 6)) | ((0x80 | (c & 0x3F)) << 8)); \ 164 memcpy(out + o, &e, 2); o += 2; i += 1; \ 165 } else if (c < 0xD800 || c >= 0xE000) { \ 166 uint32_t e = (0xE0 | (c >> 12)) | ((0x80 | ((c >> 6) & 0x3F)) << 8) | \ 167 ((0x80 | (c & 0x3F)) << 16); \ 168 memcpy(out + o, &e, 4); o += 3; i += 1; \ 169 } else if (c < 0xDC00) { \ 170 if (i + 1 >= n) return INVALID; \ 171 uint32_t lo = in[i + 1]; \ 172 if (lo < 0xDC00 || lo >= 0xE000) return INVALID; \ 173 uint32_t cp = 0x10000 + ((c - 0xD800) << 10) + (lo - 0xDC00); \ 174 uint32_t e = (0xF0 | (cp >> 18)) | ((0x80 | ((cp >> 12) & 0x3F)) << 8) | \

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 96, "limit": 18}

96 _mm_storeu_si128((__m128i *)dst, _mm256_castsi256_si128(packed)); 97 _mm_storeu_si128((__m128i *)(dst + len0), _mm256_extracti128_si256(packed, 1)); 98 return len0 + g_len2[idx1]; 99 } 100 101 // 8 units all in [0x800,0xFFFF] non-surrogate (3 bytes each) -> 24 bytes. 102 __attribute__((always_inline, target("avx2"))) 103 static inline void conv8_3(__m128i w8, uint8_t *dst) { 104 __m256i c = _mm256_cvtepu16_epi32(w8); 105 __m256i m3f = _mm256_set1_epi32(0x3F); 106 __m256i raw1 = _mm256_and_si256(_mm256_srli_epi32(c, 6), m3f); 107 __m256i raw2 = _mm256_and_si256(c, m3f); 108 __m256i src = _mm256_or_si256( 109 _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_slli_epi32(raw1, 8)), 110 _mm256_or_si256(_mm256_slli_epi32(raw2, 16), _mm256_set1_epi32(0x008080E0))); 111 const __m256i sh = _mm256_setr_epi8( 112 0,1,2, 4,5,6, 8,9,10, 12,13,14, -1,-1,-1,-1, 113 0,1,2, 4,5,6, 8,9,10, 12,13,14, -1,-1,-1,-1);

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m256i c = _mm256_cvtepu16_epi32(w8);\n __m256i m3f = _mm256_set1_epi32(0x3F);\n __m256i raw1 = _mm256_and_si256(_mm256_srli_epi32(c, 6), m3f);\n __m256i raw2 = _mm256_and_si256(c, m3f);\n __m256i src = _mm256_or_si256(\n _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_slli_epi32(raw1, 8)),\n _mm256_or_si256(_mm256_slli_epi32(raw2, 16), _mm256_set1_epi32(0x008080E0)));", "new_string": " __m256i c = _mm256_cvtepu16_epi32(w8);\n __m256i m3f = _mm256_set1_epi32(0x3F);\n // chained accumulation keeps few temporaries live (avoids spills)\n __m256i src = _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_set1_epi32(0x008080E0));\n src = _mm256_or_si256(src, _mm256_slli_epi32(_mm256_and_si256(_mm256_srli_epi32(c, 6), m3f), 8));\n src = _mm256_or_si256(src, _mm256_slli_epi32(_mm256_and_si256(c, m3f), 16));"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v18 chained conv8_3"}

verify 3.5s PASS measure 0.1s 19,960,986 instructions (given: 78,316,682) SCORE +1.9721 (3.923x)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 204, "limit": 40}

204 __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256()); 205 if (_mm256_testz_si256(small, small)) { 206 conv8_3(lo, out + o); o += 24; 207 conv8_3(hi, out + o); o += 24; 208 } else { 209 o += conv8_mixed(_mm256_cvtepu16_epi32(lo), out + o); 210 o += conv8_mixed(_mm256_cvtepu16_epi32(hi), out + o); 211 } 212 } 213 i += 16; 214 continue; 215 } 216 // surrogate present. A valid pair, viewed as a dword (high | low<<16), 217 // satisfies (dword & 0xFC00FC00) == 0xDC00D800. 218 const __m256i pmask = _mm256_set1_epi32((int)0xFC00FC00); 219 const __m256i ptag = _mm256_set1_epi32((int)0xDC00D800); 220 __m256i chk = _mm256_cmpeq_epi32(_mm256_and_si256(v, pmask), ptag); 221 if (_mm256_movemask_ps(_mm256_castsi256_ps(chk)) == 0xFF) { 222 // whole block is 8 clean pairs 223 _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v)); 224 o += 32; i += 16; 225 continue; 226 } 227 // Otherwise: vectorize ASCII runs and pair runs; rest goes scalar. 228 const __m128i pmask128 = _mm_set1_epi32((int)0xFC00FC00); 229 const __m128i ptag128 = _mm_set1_epi32((int)0xDC00D800); 230 size_t blockend = i + 16; 231 while (i < blockend) { 232 uint32_t c = in[i]; 233 if (i + 8 <= n) { 234 __m128i w = _mm_loadu_si128((const __m128i *)(in + i)); 235 if (c < 0x80) { 236 // ASCII run: pack the leading consecutive ASCII units. 237 __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), 238 _mm_setzero_si128()); 239 int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF; 240 int k = __builtin_ctz((unsigned)(~m) | 0x100); 241 _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); 242 o += (size_t)k; i += (size_t)k; 243 continue;

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 243, "limit": 22}

243 continue; 244 } 245 int mm = _mm_movemask_ps(_mm_castsi128_ps( 246 _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128))); 247 if (mm == 0xF) { // 4 pairs 248 _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); 249 o += 16; i += 8; continue; 250 } 251 if ((mm & 3) == 3) { // 2 pairs 252 _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w)); 253 o += 8; i += 4; continue; 254 } 255 if (mm & 1) { // 1 pair 256 _mm_storeu_si32(out + o, enc_pairs_word(w)); 257 o += 4; i += 2; continue; 258 } 259 } 260 STEP(); 261 } 262 } 263 264 while (i < n) STEP();

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (mm == 0xF) { // 4 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mm & 3) == 3) { // 2 pairs\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n if (mm & 1) { // 1 pair\n _mm_storeu_si32(out + o, enc_pairs_word(w));\n o += 4; i += 2; continue;\n }", "new_string": " if (mm == 0xF) { // 4 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mm & 7) == 7) { // 3 pairs\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 12; i += 6; continue;\n }\n if ((mm & 3) == 3) { // 2 pairs\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n if (mm & 1) { // ... [141 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v19 3-pair path"}

verify 2.7s PASS measure 0.1s 19,614,619 instructions (given: 78,316,682) SCORE +1.9974 (3.993x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF;\n int k = __builtin_ctz((unsigned)(~m) | 0x100);\n _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w));", "new_string": " __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(am);\n int k = __builtin_ctz((unsigned)(~m) | 0x10000) >> 1;\n _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w));"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v20 ascii-run movemask"}

verify 2.6s PASS measure 0.1s 19,672,975 instructions (given: 78,316,682) SCORE +1.9931 (3.981x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(am);\n int k = __builtin_ctz((unsigned)(~m) | 0x10000) >> 1;\n _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w));", "new_string": " __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF;\n int k = __builtin_ctz((unsigned)(~m) | 0x100);\n _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w));"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {", "new_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n __asm__ volatile(\"\" ::: \"memory\");\n conv8_3(hi, out + o); o += 24;\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v21 barrier between conv8_3"}

verify 2.5s PASS measure 0.1s 19,630,719 instructions (given: 78,316,682) SCORE +1.9962 (3.989x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n __asm__ volatile(\"\" ::: \"memory\");\n conv8_3(hi, out + o); o += 24;\n } else {", "new_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\n./grade --seed 7 2>&1 | tail -2\ncp .build/runner /tmp/runner_v19\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v19 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v19"}

measure 0.1s 19,614,619 instructions (given: 78,316,682) SCORE +1.9974 (3.993x) emojireal 6.99/unit latinreal 3.58/unit cjkreal 5.85/unit ascii 0.88/unit contrib: ascii 10% latin 26% cjk 34% emoji 30%

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 8-unit all-<0x800 compaction: idx = single-byte(ASCII) mask; 2 bytes/lane.\nstatic uint8_t g_shuf2[256][16];\nstatic uint8_t g_len2[256];", "new_string": "// 8-unit all-<0x800 compaction: idx = single-byte(ASCII) mask; 2 bytes/lane.\nstatic uint8_t g_shuf2[256][16];\nstatic uint8_t g_len2[256];\n// 4-unit ASCII-or-3-byte compaction: idx = 3-byte mask; 4 bytes/lane.\nstatic uint8_t g_shuf3[16][16];\nstatic uint8_t g_len3[16];"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " g_len2[idx] = (uint8_t)outpos;\n for (; outpos < 16; outpos++) g_shuf2[idx][outpos] = 0x80;\n }\n}", "new_string": " g_len2[idx] = (uint8_t)outpos;\n for (; outpos < 16; outpos++) g_shuf2[idx][outpos] = 0x80;\n }\n for (int idx = 0; idx < 16; idx++) {\n int outpos = 0;\n for (int j = 0; j < 4; j++) {\n g_shuf3[idx][outpos++] = (uint8_t)(4 * j);\n if ((idx >> j) & 1) {\n g_shuf3[idx][outpos++] = (uint8_t)(4 * j + 1);\n g_shuf3[idx][outpos++] = (uint8_t)(4 * j + 2);\n }\n }\n g_len3[idx] = (uint8_t)outpos;\n for (; outpos < 16; outpos++) g_shuf3[idx][outpos] = 0x80;\n }\n}"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 8 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=16).", "new_string": "// 8 units, each ASCII or 3-byte (no 2-byte, no surrogate), in 32-bit lanes ->\n// UTF-8. Returns bytes (<=24). Cheaper than conv8_mixed (one blend).\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv8_mixed3(__m256i c, uint8_t *dst) {\n __m256i m3f = _mm256_set1_epi32(0x3F);\n __m256i three_b1 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(c, 6), m3f),\n _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(c, m3f), _mm256_set1_epi32(0x80));\n __m256i m3 = _mm256_cmpgt_epi32(c, _mm256_set1_epi32(0x7FF));\n __m256i b0 = _mm256_blendv_epi8(c,\n _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_set1_epi32(0xE0)), m3);\n __m256i src = _mm256_or_si256(b0, _mm256_or_si256(_mm256_slli_epi32(three_b1, 8),\n _mm256_slli_epi32(b2, 16)));\n int mm3 = _mm256_movemask_ps(_mm256_castsi256_ps(m3));\n int idxA = mm3 & 0xF, idxB = (mm3 >> 4) & 0xF;\n __m128i pA = _mm_shuffle_epi8(_mm256_castsi256_si128(src),\n _mm_loadu_si128((const __m128i *)g_shuf3[idxA]));\n __m128i pB = _mm_shuffle_epi8(_mm256_extracti128_si256(src, 1),\n _mm_loadu_si128((const __m128i *)g_shuf3[idxB]));\n size_t lenA = g_len3[id ... [210 chars truncated]

<tool_use_error>String to replace not found in file. String: // 8 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=16).</tool_use_error>

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": "// 16 units all < 0x800 (1 or 2 bytes) -> UTF-8. Returns bytes (<=32).", "new_string": "// 8 units, each ASCII or 3-byte (no 2-byte, no surrogate), in 32-bit lanes ->\n// UTF-8. Returns bytes (<=24). Cheaper than conv8_mixed (one blend).\n__attribute__((always_inline, target(\"avx2\")))\nstatic inline size_t conv8_mixed3(__m256i c, uint8_t *dst) {\n __m256i m3f = _mm256_set1_epi32(0x3F);\n __m256i three_b1 = _mm256_or_si256(_mm256_and_si256(_mm256_srli_epi32(c, 6), m3f),\n _mm256_set1_epi32(0x80));\n __m256i b2 = _mm256_or_si256(_mm256_and_si256(c, m3f), _mm256_set1_epi32(0x80));\n __m256i m3 = _mm256_cmpgt_epi32(c, _mm256_set1_epi32(0x7FF));\n __m256i b0 = _mm256_blendv_epi8(c,\n _mm256_or_si256(_mm256_srli_epi32(c, 12), _mm256_set1_epi32(0xE0)), m3);\n __m256i src = _mm256_or_si256(b0, _mm256_or_si256(_mm256_slli_epi32(three_b1, 8),\n _mm256_slli_epi32(b2, 16)));\n int mm3 = _mm256_movemask_ps(_mm256_castsi256_ps(m3));\n int idxA = mm3 & 0xF, idxB = (mm3 >> 4) & 0xF;\n __m128i pA = _mm_shuffle_epi8(_mm256_castsi256_si128(src),\n _mm_loadu_si128((const __m128i *)g_shuf3[idxA]));\n __m128i pB = _mm_shuffle_epi8(_mm256_extracti128_si256(src, 1),\n _mm_loadu_si128((const __m128i *)g_shuf3[idxB]));\n size_t lenA = g_len3[i ... [212 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " } else {\n o += conv8_mixed(_mm256_cvtepu16_epi32(lo), out + o);\n o += conv8_mixed(_mm256_cvtepu16_epi32(hi), out + o);\n }", "new_string": " } else {\n // 2-byte lanes = (< 0x800) AND (>= 0x80)\n __m256i ascii_m = _mm256_cmpeq_epi16(\n _mm256_and_si256(v, ascii_mask), _mm256_setzero_si256());\n __m256i tb = _mm256_andnot_si256(ascii_m, small);\n if (_mm256_testz_si256(tb, tb)) { // ASCII + 3-byte only\n o += conv8_mixed3(_mm256_cvtepu16_epi32(lo), out + o);\n o += conv8_mixed3(_mm256_cvtepu16_epi32(hi), out + o);\n } else {\n o += conv8_mixed(_mm256_cvtepu16_epi32(lo), out + o);\n o += conv8_mixed(_mm256_cvtepu16_epi32(hi), out + o);\n }\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v22 conv8_mixed3"}

verify 2.4s PASS measure 0.1s 19,238,101 instructions (given: 78,316,682) SCORE +2.0254 (4.071x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v22\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v22 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v22"}

emojireal 6.99/unit latinreal 3.58/unit cjkreal 5.49/unit ascii 0.88/unit contrib: ascii 10% latin 26% cjk 32% emoji 31%

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncc -O2 -std=c17 -mavx2 -mbmi2 -g -c submission/solve.c -o /tmp/solve.o 2>/dev/null\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p&&/^$/{exit} p' > /tmp/asm.txt\n# find pure-cjk region: two vpmovzxwd near each other followed by 2 vpshufb ymm\ngrep -n 'rsp\\|vpbroadcastd\\|vpshufb.*ymm\\|vpmovzxwd' /tmp/asm.txt | sed -n '1,40p'", "description": "Check spills/remat in cjk region"}

7: f: mov %rsp,%rbp 13: 1b: and $0xffffffffffffffe0,%rsp 14: 1f: sub $0x68,%rsp 25: 59: vpbroadcastd %xmm7,%xmm12 38: 9c: vpbroadcastd %xmm4,%ymm4 45: be: vpbroadcastd %xmm1,%ymm1 56: f2: vpbroadcastd %xmm3,%xmm3 57: f7: vpbroadcastd %xmm2,%xmm2 122: 1fb: lea -0x28(%rbp),%rsp 326: 584: vpbroadcastd %xmm2,%ymm2 346: 5dc: vpbroadcastd %xmm2,%ymm2 351: 5f2: vpshufb %ymm3,%ymm0,%ymm0 389: 69e: vpbroadcastd %xmm1,%ymm1 403: 6dc: vpbroadcastd %xmm3,%ymm3 418: 724: vpmovzxwd %xmm3,%ymm3 419: 729: vpmovzxwd %xmm0,%ymm4 422: 738: vmovdqa %ymm7,-0x18(%rsp) 427: 750: vmovdqa %ymm7,0x48(%rsp) 429: 75b: vmovdqa %ymm5,-0x38(%rsp) 433: 76e: vmovdqa %ymm7,0x28(%rsp) 442: 79a: vpbroadcastd %xmm0,%ymm0 445: 7a7: vmovdqa 0x48(%rsp),%ymm7 449: 7be: vpshufb %ymm2,%ymm1,%ymm1 455: 7dc: vpshufb %ymm2,%ymm0,%ymm0 505: 8bc: vpbroadcastd %xmm1,%ymm1 507: 8c5: vmovdqa %ymm7,0x8(%rsp) 510: 8d4: vpbroadcastd %xmm2,%ymm2 512: 8dc: vmovdqa %ymm7,-0x58(%rsp) 516: 8ee: vmovaps 0x8(%rsp),%ymm9 517: 8f4: vpor 0x48(%rsp),%ymm2,%ymm11 524: 912: vmovdqa %ymm10,0x48(%rsp) 525: 918: vpor 0x28(%rsp),%ymm1,%ymm9 536: 949: vmovdqa 0x8(%rsp),%ymm7 555: 9a5: vpblendvb %ymm7,-0x58(%rsp),%ymm3,%ymm0 586: a38: vmovdqa %ymm6,0x28(%rsp) 587: a3e: vmovdqa %ymm10,-0x78(%rsp) 588: a44: vmovaps -0x78(%rsp),%ymm5 590: a4f: vpbroadcastd %xmm10,%ymm10 591: a54: vpor -0x38(%rsp),%ymm10,%ymm6 593: a5e: vmovdqa 0x8(%rsp),%ymm5

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_e22.out /tmp/runner_v22 /tmp/emojireal.bin >/dev/null 2>&1\necho \"total:\"; grep summary: /tmp/cg_e22.out\ncallgrind_annotate --inclusive=no /tmp/cg_e22.out 2>/dev/null | grep -E 'include|solve.c:utf' | head -6\necho \"--- SSE2 op breakdown ---\"\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_e22.out 2>/dev/null | awk '/annotated source.*emmintrin/{f=1} f&&/\\([0-9.]+%\\)/{print} /annotated source.*(avx2|avxintrin|xmmintrin|solve)/{if(f)exit}' | head", "description": "Annotate emoji v22"}

total: summary: 6985272 3,097,390 (44.34%) submission/solve.c:utf16_to_utf8 [/tmp/runner_v22] 2,646,686 (37.89%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h:utf16_to_utf8 932,124 (13.34%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h:utf16_to_utf8 229,405 ( 3.28%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avxintrin.h:utf16_to_utf8 79,667 ( 1.14%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/xmmintrin.h:utf16_to_utf8 -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h --- SSE2 op breakdown --- 6,985,272 (100.0%) events annotated

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 196, "limit": 14}

196 #define STEP() \ 197 do { \ 198 uint32_t c = in[i]; \ 199 if (c < 0x80) { \ 200 out[o] = (uint8_t)c; o += 1; i += 1; \ 201 } else if (c < 0x800) { \ 202 uint16_t e = (uint16_t)((0xC0 | (c >> 6)) | ((0x80 | (c & 0x3F)) << 8)); \ 203 memcpy(out + o, &e, 2); o += 2; i += 1; \ 204 } else if (c < 0xD800 || c >= 0xE000) { \ 205 uint32_t e = (0xE0 | (c >> 12)) | ((0x80 | ((c >> 6) & 0x3F)) << 8) | \ 206 ((0x80 | (c & 0x3F)) << 16); \ 207 memcpy(out + o, &e, 4); o += 3; i += 1; \ 208 } else if (c < 0xDC00) { \ 209 if (i + 1 >= n) return INVALID; \

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 223, "limit": 18}

223 size_t i = 0, o = 0; 224 const __m256i ascii_mask = _mm256_set1_epi16((short)0xFF80); 225 const __m256i surr_bits = _mm256_set1_epi16((short)0xF800); 226 const __m256i surr_tag = _mm256_set1_epi16((short)0xD800); 227 228 while (i + 16 <= n) { 229 __m256i v = _mm256_loadu_si256((const __m256i *)(in + i)); 230 if (_mm256_testz_si256(v, ascii_mask)) { 231 __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8); 232 _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed)); 233 o += 16; i += 16; 234 continue; 235 } 236 __m256i t = _mm256_and_si256(v, surr_bits); 237 __m256i is_surr = _mm256_cmpeq_epi16(t, surr_tag); 238 if (_mm256_testz_si256(is_surr, is_surr)) { 239 __m128i lo = _mm256_castsi256_si128(v); 240 __m128i hi = _mm256_extracti128_si256(v, 1);

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16; i += 16;\n continue;\n }", "new_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16; i += 16;\n if (i + 16 <= n) {\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v2, ascii_mask)) {\n __m256i p2 = _mm256_permute4x64_epi64(_mm256_packus_epi16(v2, v2), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p2));\n o += 16; i += 16;\n }\n }\n continue;\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v23 double-ascii"}

verify 2.4s PASS measure 0.1s 18,990,935 instructions (given: 78,316,682) SCORE +2.0440 (4.124x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16; i += 16;\n if (i + 16 <= n) {\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v2, ascii_mask)) {\n __m256i p2 = _mm256_permute4x64_epi64(_mm256_packus_epi16(v2, v2), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p2));\n o += 16; i += 16;\n }\n }\n continue;\n }", "new_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n do { // consume the whole ASCII run, 16 units at a time\n __m256i p = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p));\n o += 16; i += 16;\n if (i + 16 > n) break;\n v = _mm256_loadu_si256((const __m256i *)(in + i));\n } while (_mm256_testz_si256(v, ascii_mask));\n continue;\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v24 ascii run loop"}

verify 2.2s PASS measure 0.1s 19,475,279 instructions (given: 78,316,682) SCORE +2.0077 (4.021x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n do { // consume the whole ASCII run, 16 units at a time\n __m256i p = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p));\n o += 16; i += 16;\n if (i + 16 > n) break;\n v = _mm256_loadu_si256((const __m256i *)(in + i));\n } while (_mm256_testz_si256(v, ascii_mask));\n continue;\n }", "new_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16; i += 16;\n if (i + 16 <= n) {\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v2, ascii_mask)) {\n __m256i p2 = _mm256_permute4x64_epi64(_mm256_packus_epi16(v2, v2), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p2));\n o += 16; i += 16;\n }\n }\n continue;\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Confirm v23 restored"}

verify 2.3s PASS measure 0.1s 18,990,935 instructions (given: 78,316,682) SCORE +2.0440 (4.124x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v23\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v23 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('per-unit: ascii %.2f latin %.2f cjk %.2f emoji %.2f'%(a,l,c,e))\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v23"}

emojireal 6.99/unit latinreal 3.60/unit cjkreal 5.49/unit ascii 0.75/unit per-unit: ascii 0.75 latin 3.60 cjk 5.49 emoji 6.99 contrib: ascii 9% latin 27% cjk 33% emoji 31%

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 243, "limit": 30}

243 } 244 __m256i t = _mm256_and_si256(v, surr_bits); 245 __m256i is_surr = _mm256_cmpeq_epi16(t, surr_tag); 246 if (_mm256_testz_si256(is_surr, is_surr)) { 247 __m128i lo = _mm256_castsi256_si128(v); 248 __m128i hi = _mm256_extracti128_si256(v, 1); 249 if (_mm256_testz_si256(t, t)) { 250 o += conv16_2(v, out + o); 251 } else { 252 __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256()); 253 if (_mm256_testz_si256(small, small)) { 254 conv8_3(lo, out + o); o += 24; 255 conv8_3(hi, out + o); o += 24; 256 } else { 257 // 2-byte lanes = (< 0x800) AND (>= 0x80) 258 __m256i ascii_m = _mm256_cmpeq_epi16( 259 _mm256_and_si256(v, ascii_mask), _mm256_setzero_si256()); 260 __m256i tb = _mm256_andnot_si256(ascii_m, small); 261 if (_mm256_testz_si256(tb, tb)) { // ASCII + 3-byte only 262 o += conv8_mixed3(_mm256_cvtepu16_epi32(lo), out + o); 263 o += conv8_mixed3(_mm256_cvtepu16_epi32(hi), out + o); 264 } else { 265 o += conv8_mixed(_mm256_cvtepu16_epi32(lo), out + o); 266 o += conv8_mixed(_mm256_cvtepu16_epi32(hi), out + o); 267 } 268 } 269 } 270 i += 16; 271 continue; 272 }

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(is_surr, is_surr)) {\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n if (_mm256_testz_si256(t, t)) {\n o += conv16_2(v, out + o);\n } else {", "new_string": " if (_mm256_testz_si256(is_surr, is_surr)) {\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n if (_mm256_testz_si256(t, t)) {\n o += conv16_2(v, out + o);\n i += 16;\n if (i + 16 <= n) {\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v2, surr_bits)) { // next 16 also < 0x800\n o += conv16_2(v2, out + o);\n i += 16;\n }\n }\n continue;\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v25 double-latin"}

verify 2.8s PASS measure 0.1s 17,945,757 instructions (given: 78,316,682) SCORE +2.1257 (4.364x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256());\n if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n } else {", "new_string": " __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256());\n if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n if (i + 16 <= n) { // batch a second pure-3-byte block\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n __m256i t2 = _mm256_and_si256(v2, surr_bits);\n __m256i bad = _mm256_or_si256(\n _mm256_cmpeq_epi16(t2, _mm256_setzero_si256()),\n _mm256_cmpeq_epi16(t2, surr_tag));\n if (_mm256_testz_si256(bad, bad)) {\n conv8_3(_mm256_castsi256_si128(v2), out + o); o += 24;\n conv8_3(_mm256_extracti128_si256(v2, 1), out + o); o += 24;\n i += 16;\n }\n }\n continue;\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v26 double-cjk"}

verify 2.6s PASS measure 0.1s 17,777,587 instructions (given: 78,316,682) SCORE +2.1393 (4.405x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(t, t)) {\n o += conv16_2(v, out + o);\n i += 16;\n if (i + 16 <= n) {\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v2, surr_bits)) { // next 16 also < 0x800\n o += conv16_2(v2, out + o);\n i += 16;\n }\n }\n continue;\n } else {", "new_string": " if (_mm256_testz_si256(t, t)) {\n o += conv16_2(v, out + o);\n i += 16;\n while (i + 16 <= n) { // batch further < 0x800 blocks\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (!_mm256_testz_si256(v2, surr_bits)) break;\n o += conv16_2(v2, out + o);\n i += 16;\n }\n continue;\n } else {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v27 latin loop"}

verify 2.1s PASS measure 0.1s 16,970,419 instructions (given: 78,316,682) SCORE +2.2063 (4.615x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n if (i + 16 <= n) { // batch a second pure-3-byte block\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n __m256i t2 = _mm256_and_si256(v2, surr_bits);\n __m256i bad = _mm256_or_si256(\n _mm256_cmpeq_epi16(t2, _mm256_setzero_si256()),\n _mm256_cmpeq_epi16(t2, surr_tag));\n if (_mm256_testz_si256(bad, bad)) {\n conv8_3(_mm256_castsi256_si128(v2), out + o); o += 24;\n conv8_3(_mm256_extracti128_si256(v2, 1), out + o); o += 24;\n i += 16;\n }\n }\n continue;\n } else {", "new_string": " if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n while (i + 16 <= n) { // batch further pure-3-byte blocks\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n ... [614 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v28 cjk loop"}

verify 2.4s PASS measure 0.1s 16,790,824 instructions (given: 78,316,682) SCORE +2.2216 (4.664x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16; i += 16;\n if (i + 16 <= n) {\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (_mm256_testz_si256(v2, ascii_mask)) {\n __m256i p2 = _mm256_permute4x64_epi64(_mm256_packus_epi16(v2, v2), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p2));\n o += 16; i += 16;\n }\n }\n continue;\n }", "new_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n do { // batch consecutive ASCII blocks\n __m256i p = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p));\n o += 16; i += 16;\n if (i + 16 > n) break;\n v = _mm256_loadu_si256((const __m256i *)(in + i));\n } while (_mm256_testz_si256(v, ascii_mask));\n continue;\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v29 ascii loop retry"}

verify 3.4s PASS measure 0.1s 17,114,012 instructions (given: 78,316,682) SCORE +2.1941 (4.576x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n do { // batch consecutive ASCII blocks\n __m256i p = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p));\n o += 16; i += 16;\n if (i + 16 > n) break;\n v = _mm256_loadu_si256((const __m256i *)(in + i));\n } while (_mm256_testz_si256(v, ascii_mask));\n continue;\n }", "new_string": " if (_mm256_testz_si256(v, ascii_mask)) {\n __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed));\n o += 16; i += 16;\n while (i + 16 <= n) { // batch consecutive ASCII blocks\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (!_mm256_testz_si256(v2, ascii_mask)) break;\n __m256i p2 = _mm256_permute4x64_epi64(_mm256_packus_epi16(v2, v2), 0xD8);\n _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p2));\n o += 16; i += 16;\n }\n continue;\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v30 ascii while-break"}

verify 2.5s PASS measure 0.1s 16,573,331 instructions (given: 78,316,682) SCORE +2.2405 (4.725x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v30\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v30 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('per-unit: ascii %.2f latin %.2f cjk %.2f emoji %.2f'%(a,l,c,e))\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v30"}

emojireal 7.30/unit latinreal 2.33/unit cjkreal 4.77/unit ascii 0.75/unit per-unit: ascii 0.75 latin 2.33 cjk 4.77 emoji 7.30 contrib: ascii 10% latin 20% cjk 33% emoji 37%

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 283, "limit": 50}

283 o += conv8_mixed3(_mm256_cvtepu16_epi32(hi), out + o); 284 } else { 285 o += conv8_mixed(_mm256_cvtepu16_epi32(lo), out + o); 286 o += conv8_mixed(_mm256_cvtepu16_epi32(hi), out + o); 287 } 288 } 289 } 290 i += 16; 291 continue; 292 } 293 // surrogate present. A valid pair, viewed as a dword (high | low<<16), 294 // satisfies (dword & 0xFC00FC00) == 0xDC00D800. 295 const __m256i pmask = _mm256_set1_epi32((int)0xFC00FC00); 296 const __m256i ptag = _mm256_set1_epi32((int)0xDC00D800); 297 __m256i chk = _mm256_cmpeq_epi32(_mm256_and_si256(v, pmask), ptag); 298 if (_mm256_movemask_ps(_mm256_castsi256_ps(chk)) == 0xFF) { 299 // whole block is 8 clean pairs 300 _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v)); 301 o += 32; i += 16; 302 continue; 303 } 304 // Otherwise: vectorize ASCII runs and pair runs; rest goes scalar. 305 const __m128i pmask128 = _mm_set1_epi32((int)0xFC00FC00); 306 const __m128i ptag128 = _mm_set1_epi32((int)0xDC00D800); 307 size_t blockend = i + 16; 308 while (i < blockend) { 309 uint32_t c = in[i]; 310 if (i + 8 <= n) { 311 __m128i w = _mm_loadu_si128((const __m128i *)(in + i)); 312 if (c < 0x80) { 313 // ASCII run: pack the leading consecutive ASCII units. 314 __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), 315 _mm_setzero_si128()); 316 int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF; 317 int k = __builtin_ctz((unsigned)(~m) | 0x100); 318 _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); 319 o += (size_t)k; i += (size_t)k; 320 continue; 321 } 322 int mm = _mm_movemask_ps(_mm_castsi128_ps( 323 _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128))); 324 if (mm == 0xF) { // 4 pairs 325 _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); 326 o += 16; i += 8; continue; 327 ... [314 chars truncated]

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 332, "limit": 20}

332 if ((mm & 3) == 3) { // 2 pairs 333 _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w)); 334 o += 8; i += 4; continue; 335 } 336 if (mm & 1) { // 1 pair 337 _mm_storeu_si32(out + o, enc_pairs_word(w)); 338 o += 4; i += 2; continue; 339 } 340 } 341 STEP(); 342 } 343 } 344 345 while (i < n) STEP(); 346 return o; 347 } 348

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " // surrogate present. A valid pair, viewed as a dword (high | low<<16),\n // satisfies (dword & 0xFC00FC00) == 0xDC00D800.\n const __m256i pmask = _mm256_set1_epi32((int)0xFC00FC00);\n const __m256i ptag = _mm256_set1_epi32((int)0xDC00D800);\n __m256i chk = _mm256_cmpeq_epi32(_mm256_and_si256(v, pmask), ptag);\n if (_mm256_movemask_ps(_mm256_castsi256_ps(chk)) == 0xFF) {\n // whole block is 8 clean pairs\n _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(v));\n o += 32; i += 16;\n continue;\n }\n // Otherwise: vectorize ASCII runs and pair runs; rest goes scalar.\n const __m128i pmask128 = _mm_set1_epi32((int)0xFC00FC00);\n const __m128i ptag128 = _mm_set1_epi32((int)0xDC00D800);\n size_t blockend = i + 16;\n while (i < blockend) {\n uint32_t c = in[i];\n if (i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n if (c < 0x80) {\n // ASCII run: pack the leading consecutive ASCII units.\n __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & ... [4040 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v31 emoji batch loop"}

build 1.1s verify 2.5s PASS measure 0.1s 15,507,099 instructions (given: 78,316,682) SCORE +2.3364 (5.050x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v31\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v31 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('per-unit: ascii %.2f latin %.2f cjk %.2f emoji %.2f'%(a,l,c,e))\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v31"}

emojireal 5.96/unit latinreal 2.33/unit cjkreal 4.71/unit ascii 0.75/unit per-unit: ascii 0.75 latin 2.33 cjk 4.71 emoji 5.96 contrib: ascii 11% latin 21% cjk 35% emoji 33%

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 244, "limit": 50}

244 __m256i is_surr = _mm256_cmpeq_epi16(t, surr_tag); 245 if (_mm256_testz_si256(is_surr, is_surr)) { 246 __m128i lo = _mm256_castsi256_si128(v); 247 __m128i hi = _mm256_extracti128_si256(v, 1); 248 if (_mm256_testz_si256(t, t)) { 249 o += conv16_2(v, out + o); 250 i += 16; 251 while (i + 16 <= n) { // batch further < 0x800 blocks 252 __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i)); 253 if (!_mm256_testz_si256(v2, surr_bits)) break; 254 o += conv16_2(v2, out + o); 255 i += 16; 256 } 257 continue; 258 } else { 259 __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256()); 260 if (_mm256_testz_si256(small, small)) { 261 conv8_3(lo, out + o); o += 24; 262 conv8_3(hi, out + o); o += 24; 263 i += 16; 264 while (i + 16 <= n) { // batch further pure-3-byte blocks 265 __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i)); 266 __m256i t2 = _mm256_and_si256(v2, surr_bits); 267 __m256i bad = _mm256_or_si256( 268 _mm256_cmpeq_epi16(t2, _mm256_setzero_si256()), 269 _mm256_cmpeq_epi16(t2, surr_tag)); 270 if (!_mm256_testz_si256(bad, bad)) break; 271 conv8_3(_mm256_castsi256_si128(v2), out + o); o += 24; 272 conv8_3(_mm256_extracti128_si256(v2, 1), out + o); o += 24; 273 i += 16; 274 } 275 continue; 276 } else { 277 // 2-byte lanes = (< 0x800) AND (>= 0x80) 278 __m256i ascii_m = _mm256_cmpeq_epi16( 279 _mm256_and_si256(v, ascii_mask), _mm256_setzero_si256()); 280 __m256i tb = _mm256_andnot_si256(ascii_m, small); 281 if (_mm256_testz_si256(tb, tb)) { // ASCII + 3-byte only 282 o += conv8_mixed3(_mm256_cvtepu16_epi32(lo), out + o); 283 o += conv8_mixed3(_mm256_cvtepu16_epi32(hi), out + o); 284 } else { 285 o += conv8_mixed(_mm256_cvtepu16_epi32(lo), ... [306 chars truncated]

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " } else {\n __m256i small = _mm256_cmpeq_epi16(t, _mm256_setzero_si256());\n if (_mm256_testz_si256(small, small)) {\n conv8_3(lo, out + o); o += 24;\n conv8_3(hi, out + o); o += 24;\n i += 16;\n while (i + 16 <= n) { // batch further pure-3-byte blocks\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n __m256i t2 = _mm256_and_si256(v2, surr_bits);\n __m256i bad = _mm256_or_si256(\n _mm256_cmpeq_epi16(t2, _mm256_setzero_si256()),\n _mm256_cmpeq_epi16(t2, surr_tag));\n if (!_mm256_testz_si256(bad, bad)) break;\n conv8_3(_mm256_castsi256_si128(v2), out + o); o += 24;\n conv8_3(_mm256_extracti128_si256(v2, 1), out + o); o += 24;\n i += 16;\n }\n continue;\n } else {\n // 2-byte lanes = (< 0x800) AND (>= 0x80)\n __m256i ascii_m = _mm256_cmpeq_epi16(\n _mm256_and_si256(v, ascii_mask), _mm256_setzero_si256());\n __m256i tb = _mm256_andnot_si256(ascii_m, small);\n if (_ ... [2455 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(is_surr, is_surr)) {\n __m128i lo = _mm256_castsi256_si128(v);\n __m128i hi = _mm256_extracti128_si256(v, 1);\n if (_mm256_testz_si256(t, t)) {", "new_string": " if (_mm256_testz_si256(is_surr, is_surr)) {\n if (_mm256_testz_si256(t, t)) {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v32 unified cjk batch"}

build 2.0s verify 3.1s PASS measure 0.1s 15,931,943 instructions (given: 78,316,682) SCORE +2.2974 (4.916x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " if (_mm256_testz_si256(is_surr, is_surr)) {\n if (_mm256_testz_si256(t, t)) {\n o += conv16_2(v, out + o);\n i += 16;\n while (i + 16 <= n) { // batch further < 0x800 blocks\n __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i));\n if (!_mm256_testz_si256(v2, surr_bits)) break;\n o += conv16_2(v2, out + o);\n i += 16;\n }\n continue;\n }\n // has some >= 0x800 (3-byte). Batch pure-3-byte and mixed\n // (ASCII/2-byte + 3-byte) blocks until surrogate or all-<0x800.\n for (;;) {\n __m256i small = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits),\n _mm256_setzero_si256());\n if (_mm256_testz_si256(small, small)) { // pure 3-byte\n conv8_3(_mm256_castsi256_si128(v), out + o); o += 24;\n conv8_3(_mm256_extracti128_si256(v, 1), out + o); o += 24;\n } else {\n __m256i ascii_m = _mm256_cmpeq_epi16(\n _mm256_and_si256(v, ascii_mask), _mm256_setzero_si256());\n __m256i tb = _mm256_andnot_si256(ascii_m, small);\n if (_mm256_testz_si25 ... [4673 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -4", "description": "Grade v33 hybrid cjk batch"}

build 1.6s verify 2.6s PASS measure 0.1s 15,231,850 instructions (given: 78,316,682) SCORE +2.3622 (5.142x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v33\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v33 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('per-unit: ascii %.2f latin %.2f cjk %.2f emoji %.2f'%(a,l,c,e))\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"\necho \"--- other seeds ---\"\nfor s in 1 42 999; do ./grade --seed $s 2>&1 | grep SCORE | sed \"s/^/seed $s: /\"; done", "description": "Re-measure v33 + seeds"}

emojireal 5.98/unit latinreal 2.33/unit cjkreal 4.38/unit ascii 0.75/unit per-unit: ascii 0.75 latin 2.33 cjk 4.38 emoji 5.98 contrib: ascii 11% latin 22% cjk 33% emoji 34% --- other seeds --- seed 1: SCORE +2.3541 (5.113x) seed 42: SCORE +2.3534 (5.110x) seed 999: SCORE +2.3596 (5.132x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nvalgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no \\\n --callgrind-out-file=/tmp/cg_e33.out /tmp/runner_v33 /tmp/emojireal.bin >/dev/null 2>&1\necho \"total:\"; grep summary: /tmp/cg_e33.out\ncallgrind_annotate --inclusive=no /tmp/cg_e33.out 2>/dev/null | grep -E 'include|solve.c:utf' | head -6\ncallgrind_annotate --auto=yes --inclusive=no /tmp/cg_e33.out 2>/dev/null | awk '/annotated source.*emmintrin/{f=1} f&&/\\([0-9.]+%\\)/{print} /annotated source.*avx2/{if(f)exit}' | head -6", "description": "Annotate emoji v33"}

total: summary: 5981460 2,468,959 (41.28%) submission/solve.c:utf16_to_utf8 [/tmp/runner_v33] 2,220,351 (37.12%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h:utf16_to_utf8 927,014 (15.50%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h:utf16_to_utf8 307,192 ( 5.14%) /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avxintrin.h:utf16_to_utf8 -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/emmintrin.h -- Auto-annotated source: /usr/lib/gcc/x86_64-pc-linux-gnu/15.2.1/include/avx2intrin.h 5,923,516 (99.03%) events annotated

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 312, "limit": 38}

312 __m256i vv = _mm256_loadu_si256((const __m256i *)(in + i)); 313 __m256i c2 = _mm256_cmpeq_epi32(_mm256_and_si256(vv, pmask), ptag); 314 if (_mm256_movemask_ps(_mm256_castsi256_ps(c2)) == 0xFF) { 315 _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(vv)); 316 o += 32; i += 16; continue; 317 } 318 } 319 if (i + 8 <= n) { 320 __m128i w = _mm_loadu_si128((const __m128i *)(in + i)); 321 uint32_t c = in[i]; 322 if (c < 0x80) { 323 __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), 324 _mm_setzero_si128()); 325 int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF; 326 int k = __builtin_ctz((unsigned)(~m) | 0x100); 327 _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); 328 o += (size_t)k; i += (size_t)k; 329 continue; 330 } 331 int mm = _mm_movemask_ps(_mm_castsi128_ps( 332 _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128))); 333 if (mm == 0xF) { 334 _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); 335 o += 16; i += 8; continue; 336 } 337 if ((mm & 7) == 7) { 338 _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); 339 o += 12; i += 6; continue; 340 } 341 if ((mm & 3) == 3) { 342 _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w)); 343 o += 8; i += 4; continue; 344 } 345 if (mm & 1) { 346 _mm_storeu_si32(out + o, enc_pairs_word(w)); 347 o += 4; i += 2; continue; 348 } 349 }

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " int mm = _mm_movemask_ps(_mm_castsi128_ps(\n _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128)));\n if (mm == 0xF) {\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mm & 7) == 7) {\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 12; i += 6; continue;\n }\n if ((mm & 3) == 3) {\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n if (mm & 1) {\n _mm_storeu_si32(out + o, enc_pairs_word(w));\n o += 4; i += 2; continue;\n }\n }", "new_string": " int mm = _mm_movemask_ps(_mm_castsi128_ps(\n _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128)));\n int np = __builtin_ctz((unsigned)~mm); // leading valid pairs, 0..4\n if (np) {\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += (size_t)(np * 4); i += (size_t)(np * 2); continue;\n }\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v34 ctz pair count"}

verify 2.2s PASS measure 0.1s 15,470,764 instructions (given: 78,316,682) SCORE +2.3398 (5.062x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " int mm = _mm_movemask_ps(_mm_castsi128_ps(\n _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128)));\n int np = __builtin_ctz((unsigned)~mm); // leading valid pairs, 0..4\n if (np) {\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += (size_t)(np * 4); i += (size_t)(np * 2); continue;\n }\n }", "new_string": " int mm = _mm_movemask_ps(_mm_castsi128_ps(\n _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128)));\n if (mm == 0xF) {\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 16; i += 8; continue;\n }\n if ((mm & 7) == 7) {\n _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w));\n o += 12; i += 6; continue;\n }\n if ((mm & 3) == 3) {\n _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w));\n o += 8; i += 4; continue;\n }\n if (mm & 1) {\n _mm_storeu_si32(out + o, enc_pairs_word(w));\n o += 4; i += 2; continue;\n }\n }"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 305, "limit": 16}

305 // pair runs across block boundaries until non-pair/ASCII content. 306 const __m256i pmask = _mm256_set1_epi32((int)0xFC00FC00); 307 const __m256i ptag = _mm256_set1_epi32((int)0xDC00D800); 308 const __m128i pmask128 = _mm_set1_epi32((int)0xFC00FC00); 309 const __m128i ptag128 = _mm_set1_epi32((int)0xDC00D800); 310 for (;;) { 311 if (i + 16 <= n) { // whole 16 = 8 clean pairs 312 __m256i vv = _mm256_loadu_si256((const __m256i *)(in + i)); 313 __m256i c2 = _mm256_cmpeq_epi32(_mm256_and_si256(vv, pmask), ptag); 314 if (_mm256_movemask_ps(_mm256_castsi256_ps(c2)) == 0xFF) { 315 _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(vv)); 316 o += 32; i += 16; continue; 317 } 318 } 319 if (i + 8 <= n) { 320 __m128i w = _mm_loadu_si128((const __m128i *)(in + i));

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " for (;;) {\n if (i + 16 <= n) { // whole 16 = 8 clean pairs\n __m256i vv = _mm256_loadu_si256((const __m256i *)(in + i));\n __m256i c2 = _mm256_cmpeq_epi32(_mm256_and_si256(vv, pmask), ptag);\n if (_mm256_movemask_ps(_mm256_castsi256_ps(c2)) == 0xFF) {\n _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(vv));\n o += 32; i += 16; continue;\n }\n }\n if (i + 8 <= n) {", "new_string": " for (;;) {\n if (i + 8 <= n) {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v35 no 8-pair check"}

verify 2.3s PASS measure 0.1s 15,245,474 instructions (given: 78,316,682) SCORE +2.3609 (5.137x)

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " for (;;) {\n if (i + 8 <= n) {", "new_string": " for (;;) {\n if (i + 16 <= n) { // whole 16 = 8 clean pairs\n __m256i vv = _mm256_loadu_si256((const __m256i *)(in + i));\n __m256i c2 = _mm256_cmpeq_epi32(_mm256_and_si256(vv, pmask), ptag);\n if (_mm256_movemask_ps(_mm256_castsi256_ps(c2)) == 0xFF) {\n _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(vv));\n o += 32; i += 16; continue;\n }\n }\n if (i + 8 <= n) {"}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 310, "limit": 45}

310 for (;;) { 311 if (i + 16 <= n) { // whole 16 = 8 clean pairs 312 __m256i vv = _mm256_loadu_si256((const __m256i *)(in + i)); 313 __m256i c2 = _mm256_cmpeq_epi32(_mm256_and_si256(vv, pmask), ptag); 314 if (_mm256_movemask_ps(_mm256_castsi256_ps(c2)) == 0xFF) { 315 _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(vv)); 316 o += 32; i += 16; continue; 317 } 318 } 319 if (i + 8 <= n) { 320 __m128i w = _mm_loadu_si128((const __m128i *)(in + i)); 321 uint32_t c = in[i]; 322 if (c < 0x80) { 323 __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)), 324 _mm_setzero_si128()); 325 int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF; 326 int k = __builtin_ctz((unsigned)(~m) | 0x100); 327 _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w)); 328 o += (size_t)k; i += (size_t)k; 329 continue; 330 } 331 int mm = _mm_movemask_ps(_mm_castsi128_ps( 332 _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128))); 333 if (mm == 0xF) { 334 _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); 335 o += 16; i += 8; continue; 336 } 337 if ((mm & 7) == 7) { 338 _mm_storeu_si128((__m128i *)(out + o), enc_pairs_word(w)); 339 o += 12; i += 6; continue; 340 } 341 if ((mm & 3) == 3) { 342 _mm_storel_epi64((__m128i *)(out + o), enc_pairs_word(w)); 343 o += 8; i += 4; continue; 344 } 345 if (mm & 1) { 346 _mm_storeu_si32(out + o, enc_pairs_word(w)); 347 o += 4; i += 2; continue; 348 } 349 } 350 break; // near end, or a non-pair/non-ASCII unit 351 } 352 if (i < n) STEP(); // make progress on the stuck unit / tail 353 continue; 354 }

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " for (;;) {\n if (i + 16 <= n) { // whole 16 = 8 clean pairs\n __m256i vv = _mm256_loadu_si256((const __m256i *)(in + i));\n __m256i c2 = _mm256_cmpeq_epi32(_mm256_and_si256(vv, pmask), ptag);\n if (_mm256_movemask_ps(_mm256_castsi256_ps(c2)) == 0xFF) {\n _mm256_storeu_si256((__m256i *)(out + o), enc_pairs_word256(vv));\n o += 32; i += 16; continue;\n }\n }\n if (i + 8 <= n) {\n __m128i w = _mm_loadu_si128((const __m128i *)(in + i));\n uint32_t c = in[i];\n if (c < 0x80) {\n __m128i am = _mm_cmpeq_epi16(_mm_and_si128(w, _mm_set1_epi16((short)0xFF80)),\n _mm_setzero_si128());\n int m = _mm_movemask_epi8(_mm_packs_epi16(am, am)) & 0xFF;\n int k = __builtin_ctz((unsigned)(~m) | 0x100);\n _mm_storel_epi64((__m128i *)(out + o), _mm_packus_epi16(w, w));\n o += (size_t)k; i += (size_t)k;\n continue;\n }\n int mm = _mm_movemask_ps(_mm_castsi128_ps(\n _mm_cmpeq_epi32(_mm_and_si128(w, pmask128), ptag128)));\n if (mm == 0xF) {\n _mm_storeu_s ... [2876 chars truncated]

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -3", "description": "Grade v36 shared load emoji"}

verify 2.3s PASS measure 0.1s 14,970,505 instructions (given: 78,316,682) SCORE +2.3872 (5.231x)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncp .build/runner /tmp/runner_v36\nfor c in emojireal latinreal cjkreal ascii; do\n valgrind --tool=callgrind --toggle-collect=utf16_to_utf8 --collect-atstart=no --dump-line=no \\\n --callgrind-out-file=/tmp/cg_$c.out /tmp/runner_v36 /tmp/$c.bin >/dev/null 2>&1\n printf \"%-10s \" $c; grep '^summary:' /tmp/cg_$c.out | awk '{printf \"%.2f/unit\\n\", $2/1000000}'\ndone\npython3 -c \"\ndef s(p):\n for line in open(p):\n if line.startswith('summary:'): return int(line.split()[1])/1000000\na=s('/tmp/cg_ascii.out');l=s('/tmp/cg_latinreal.out');c=s('/tmp/cg_cjkreal.out');e=s('/tmp/cg_emojireal.out')\ntot=400000*a+250000*l+200000*c+150000*e\nprint('per-unit: ascii %.2f latin %.2f cjk %.2f emoji %.2f'%(a,l,c,e))\nprint('contrib: ascii %.0f%% latin %.0f%% cjk %.0f%% emoji %.0f%%'%(100*400000*a/tot,100*250000*l/tot,100*200000*c/tot,100*150000*e/tot))\n\"", "description": "Re-measure v36"}

emojireal 5.68/unit latinreal 2.33/unit cjkreal 4.38/unit ascii 0.75/unit per-unit: ascii 0.75 latin 2.33 cjk 4.38 emoji 5.68 contrib: ascii 11% latin 22% cjk 34% emoji 33%

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\ncc -O2 -std=c17 -mavx2 -mbmi2 -g -c submission/solve.c -o /tmp/solve.o 2>/dev/null\nobjdump -d --no-show-raw-insn /tmp/solve.o | awk '/<utf16_to_utf8>:/{p=1} p&&/^$/{exit} p' > /tmp/asm.txt\necho \"total function insns:\"; grep -cE '^\\s+[0-9a-f]+:' /tmp/asm.txt\necho \"spills (rsp stores):\"; grep -cE 'vmov.*,.*\\(%rsp\\)|vmov.*,-0x[0-9a-f]+\\(%rbp\\)' /tmp/asm.txt\necho \"constant broadcasts:\"; grep -cE 'vpbroadcast' /tmp/asm.txt\n# Find the pure-cjk do-while loop (two vpshufb ymm close together = 2 conv8_3)\ngrep -nE 'vpshufb.*ymm|vpmovzxwd|vmovdqa.*rsp|vpbroadcastd' /tmp/asm.txt | sed -n '1,30p'", "description": "Check cjk asm state"}

total function insns: 797 spills (rsp stores): 4 constant broadcasts: 19 24: 4c: vpbroadcastd %xmm14,%ymm14 48: d0: vmovdqa 0x8(%rsp),%ymm7 113: 1ff: vpbroadcastd %xmm4,%ymm4 114: 204: vpmovzxwd %xmm2,%ymm2 115: 209: vpmovzxwd %xmm0,%ymm0 120: 222: vmovdqa %ymm6,-0x38(%rsp) 125: 23a: vpbroadcastd %xmm5,%ymm5 127: 243: vmovdqa %ymm10,-0x58(%rsp) 132: 25a: vmovdqa %ymm7,0x8(%rsp) 148: 29f: vmovdqa %ymm9,-0x78(%rsp) 160: 2dd: vpbroadcastd %xmm9,%ymm9 254: 465: vpbroadcastd %xmm2,%ymm2 268: 4a2: vpmovzxwd %xmm0,%ymm1 276: 4ca: vpmovzxwd %xmm0,%ymm0 282: 4e5: vpshufb %ymm15,%ymm1,%ymm1 293: 51c: vpshufb %ymm15,%ymm0,%ymm0 309: 56d: vpbroadcastd %xmm5,%ymm5 330: 5ca: vpbroadcastd %xmm6,%ymm6 336: 5e5: vpshufb %ymm4,%ymm0,%ymm0 371: 67f: vpshufb %ymm4,%ymm0,%ymm0 399: 6fc: vpbroadcastd %xmm2,%xmm4 400: 701: vpbroadcastd %xmm2,%ymm2 536: 971: vpbroadcastd %xmm1,%xmm1 550: 9b7: vpbroadcastd %xmm8,%xmm8 567: a0d: vpbroadcastd %xmm1,%ymm1 582: a56: vpbroadcastd %xmm9,%ymm9 601: ab6: vpbroadcastd %xmm1,%xmm1 614: af7: vpbroadcastd %xmm9,%xmm9 632: b51: vpbroadcastd %xmm1,%xmm1 646: b97: vpbroadcastd %xmm9,%xmm9

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\necho \"=== build warnings (gcc, grader flags) ===\"\ncc -O2 -std=c17 -fno-lto -g -I submission -c submission/solve.c -o /tmp/solvecheck.o -Wall -Wextra 2>&1 | head -20 || echo \"(clean)\"\necho \"=== FULL gate + seed 7 ===\"\n./grade --full --seed 7 2>&1 | tail -5", "description": "Full gate + warnings"}

=== build warnings (gcc, grader flags) === === FULL gate + seed 7 === build 1.3s verify 2.5s PASS (FULL gate) measure 0.1s 14,970,505 instructions (given: 78,316,682) SCORE +2.3872 (5.231x)

{"file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "offset": 228, "limit": 40}

228 while (i + 16 <= n) { 229 __m256i v = _mm256_loadu_si256((const __m256i *)(in + i)); 230 if (_mm256_testz_si256(v, ascii_mask)) { 231 __m256i packed = _mm256_permute4x64_epi64(_mm256_packus_epi16(v, v), 0xD8); 232 _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(packed)); 233 o += 16; i += 16; 234 while (i + 16 <= n) { // batch consecutive ASCII blocks 235 __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i)); 236 if (!_mm256_testz_si256(v2, ascii_mask)) break; 237 __m256i p2 = _mm256_permute4x64_epi64(_mm256_packus_epi16(v2, v2), 0xD8); 238 _mm_storeu_si128((__m128i *)(out + o), _mm256_castsi256_si128(p2)); 239 o += 16; i += 16; 240 } 241 continue; 242 } 243 __m256i t = _mm256_and_si256(v, surr_bits); 244 __m256i is_surr = _mm256_cmpeq_epi16(t, surr_tag); 245 if (_mm256_testz_si256(is_surr, is_surr)) { 246 if (_mm256_testz_si256(t, t)) { 247 o += conv16_2(v, out + o); 248 i += 16; 249 while (i + 16 <= n) { // batch further < 0x800 blocks 250 __m256i v2 = _mm256_loadu_si256((const __m256i *)(in + i)); 251 if (!_mm256_testz_si256(v2, surr_bits)) break; 252 o += conv16_2(v2, out + o); 253 i += 16; 254 } 255 continue; 256 } 257 // has some >= 0x800 (3-byte). Batch pure-3-byte and mixed 258 // (ASCII + 3-byte) blocks; the cheap `bad` test keeps pure fast. 259 for (;;) { 260 __m256i small = _mm256_cmpeq_epi16(_mm256_and_si256(v, surr_bits), 261 _mm256_setzero_si256()); 262 if (_mm256_testz_si256(small, small)) { // pure 3-byte run 263 do { 264 conv8_3(_mm256_castsi256_si128(v), out + o); o += 24; 265 conv8_3(_mm256_extracti128_si256(v, 1), out + o); o += 24; 266 i += 16; 267 if (i + 16 > n) goto bmp3_done;

{"replace_all": false, "file_path": "/tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c", "old_string": " // has some >= 0x800 (3-byte). Batch pure-3-byte and mixed\n // (ASCII + 3-byte) blocks; the cheap `bad` test keeps pure fast.", "new_string": " // has some >= 0x800 (3-byte). Batch pure-3-byte runs with a cheap\n // per-block test, and handle interspersed mixed (ASCII/2-byte +\n // 3-byte) blocks inline, until a surrogate or all-<0x800 block."}

The file /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode/submission/solve.c has been updated successfully. (file state is current in your context — no need to Read it back)

{"command": "cd /tmp/bench4-cc-utf16-transcode/tasks/utf16-transcode\nfor s in 7 1 42 999 31337 2024; do ./grade --seed $s 2>&1 | grep SCORE | sed \"s/^/seed $s: /\"; done", "description": "Final multi-seed validation"}

seed 7: SCORE +2.3872 (5.231x) seed 1: SCORE +2.3793 (5.203x) seed 42: SCORE +2.3785 (5.200x) seed 999: SCORE +2.3850 (5.223x) seed 31337: SCORE +2.3893 (5.239x) seed 2024: SCORE +2.3903 (5.243x)

{"command": "ls /home/jeremy/.claude/projects/-tmp-bench4-cc-utf16-transcode/memory/ 2>/dev/null && echo \"---\" && cat /home/jeremy/.claude/projects/-tmp-bench4-cc-utf16-transcode/memory/MEMORY.md 2>/dev/null || echo \"(no memory dir yet)\"", "description": "Check memory dir"}

(no memory dir yet)

{"file_path": "/home/jeremy/.claude/projects/-tmp-bench4-cc-utf16-transcode/memory/jcode-bench-simd-tasks.md", "content": "---\nname: jcode-bench-simd-tasks\ndescription: How the jcode bench transcode/parse tasks are scored and what wins\nmetadata:\n type: project\n---\n\njcode bench tasks (utf16-transcode, json-unescape, float-print) give a working\nscalar `submission/solve.c`; you make it faster. Correctness is an exhaustive\ngate (`./grade`), score = log2(given_cost / your_cost) via callgrind.\n\n**Why:** the scoring harness (`harness/grade.py`) sums callgrind lines matching\n`^\\d+ \\d+`, which happens to count the function's total Ir ~5\u00d7 plus a tiny\nper-call constant. So the metric is monotonic in total instructions executed\ninside the measured function \u2014 just minimize Ir; the 5\u00d7 cancels in the ratio.\n\n**How to apply:**\n- AVX2/BMI2 are available; enable per-function with `__attribute__((target(\"avx2\")))` even though the grader compiles at plain -O2 (no -march). SSE2 needs no attribute.\n- The runner calls the function once *per record*, so within a call the input is a single corpus regime (long homogeneous runs).\n- Biggest lever for utf16-transcode (0\u2192+2.39, i.e. 5.2\u00d7): tier by block class\n (ASCII / all-<0x800 / all-3-byte / mixed / surrogate-pairs) with pshufb\n compaction tables, THEN **batch consecutive same-class 16-byte blocks in a\n tight inner `while(...break)` loop** to eliminate per-block dispatch \u2014 this\n alone took i ... [595 chars truncated]

File created successfully at: /home/jeremy/.claude/projects/-tmp-bench4-cc-utf16-transcode/memory/jcode-bench-simd-tasks.md (file state is current in your context — no need to Read it back)

{"file_path": "/home/jeremy/.claude/projects/-tmp-bench4-cc-utf16-transcode/memory/MEMORY.md", "content": "- [jcode bench SIMD tasks](jcode-bench-simd-tasks.md) \u2014 scoring (~5\u00d7 Ir ratio), AVX2 tiering + block-batching won 5.2\u00d7 on utf16-transcode\n"}

File created successfully at: /home/jeremy/.claude/projects/-tmp-bench4-cc-utf16-transcode/memory/MEMORY.md (file state is current in your context — no need to Read it back)

{"command": "./grade --seed 7 2>&1 | tail -5", "description": "Final confirmation grade"}

build 1.2s verify 2.3s PASS measure 0.1s 14,970,505 instructions (given: 78,316,682) SCORE +2.3872 (5.231x)