59 lines
2.2 KiB
C
59 lines
2.2 KiB
C
|
// bench_fast_box.h - BenchFast Mode (Phase 20-2)
|
||
|
|
// Purpose: Measure HAKMEM's structural performance ceiling by removing ALL safety costs
|
||
|
|
// WARNING: UNSAFE - Benchmark-only mode, DO NOT use in production
|
||
|
|
//
|
||
|
|
// Design Philosophy:
|
||
|
|
// - Alloc: Trust size → instant Tiny path (no classify_ptr, no Pool/Mid checks)
|
||
|
|
// - Free: Trust header → instant Tiny path (no registry, no mincore, no guards)
|
||
|
|
// - Goal: Minimal instruction count (6-8 alloc, 3-5 free) to measure structural limits
|
||
|
|
//
|
||
|
|
// Enable with: HAKMEM_BENCH_FAST_MODE=1
|
||
|
|
// Expected: +65-100% performance (15.7M → 25-30M ops/s)
|
||
|
|
|
||
|
|
#ifndef HAK_BOX_BENCH_FAST_H
|
||
|
|
#define HAK_BOX_BENCH_FAST_H
|
||
|
|
|
||
|
|
#include <stddef.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
|
||
|
|
// BenchFast mode enabled (ENV cached at first call)
|
||
|
|
// Returns: 1 if enabled, 0 if disabled
|
||
|
|
static inline int bench_fast_enabled(void) {
|
||
|
|
static int cached = -1;
|
||
|
|
if (__builtin_expect(cached == -1, 0)) {
|
||
|
|
const char* env = getenv("HAKMEM_BENCH_FAST_MODE");
|
||
|
|
cached = (env && *env && *env != '0') ? 1 : 0;
|
||
|
|
if (cached) {
|
||
|
|
fprintf(stderr, "[HAKMEM][BENCH_FAST] WARNING: Unsafe benchmark mode enabled!\n");
|
||
|
|
fprintf(stderr, "[HAKMEM][BENCH_FAST] DO NOT use in production - safety costs removed\n");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return cached;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Exposed init guard so wrappers can avoid BenchFast during preallocation
|
||
|
|
extern __thread int bench_fast_init_in_progress;
|
||
|
|
|
||
|
|
// BenchFast alloc (Tiny-only, no safety checks)
|
||
|
|
// Preconditions: size <= 1024 (Tiny range)
|
||
|
|
// Returns: pointer on success, NULL on failure
|
||
|
|
void* bench_fast_alloc(size_t size);
|
||
|
|
|
||
|
|
// BenchFast free (header-based, no validation)
|
||
|
|
// Preconditions: ptr from bench_fast_alloc(), header is valid
|
||
|
|
void bench_fast_free(void* ptr);
|
||
|
|
|
||
|
|
// BenchFast init - Preallocate pool before benchmark
|
||
|
|
// Purpose: Avoid recursion by pre-populating TLS SLL with blocks
|
||
|
|
// Call this BEFORE starting benchmark (uses normal allocator path)
|
||
|
|
// Returns: Total number of blocks preallocated, or 0 if disabled
|
||
|
|
// Recommended: 50,000 blocks per class (C2-C7) = 300,000 total
|
||
|
|
int bench_fast_init(void);
|
||
|
|
|
||
|
|
// BenchFast stats - Print remaining blocks per class (debug/verification)
|
||
|
|
// Optional: Use after benchmark to verify pool wasn't exhausted
|
||
|
|
void bench_fast_stats(void);
|
||
|
|
|
||
|
|
#endif // HAK_BOX_BENCH_FAST_H
|