diff options
Diffstat (limited to 'util')
| -rw-r--r-- | util/bufferiszero.c | 191 | ||||
| -rw-r--r-- | util/cpuinfo-loongarch.c | 1 |
2 files changed, 2 insertions, 190 deletions
diff --git a/util/bufferiszero.c b/util/bufferiszero.c index 11c080e..522146d 100644 --- a/util/bufferiszero.c +++ b/util/bufferiszero.c @@ -81,196 +81,7 @@ static bool buffer_is_zero_int_ge256(const void *buf, size_t len) return t == 0; } -#if defined(CONFIG_AVX2_OPT) || defined(__SSE2__) -#include <immintrin.h> - -/* Helper for preventing the compiler from reassociating - chains of binary vector operations. */ -#define SSE_REASSOC_BARRIER(vec0, vec1) asm("" : "+x"(vec0), "+x"(vec1)) - -/* Note that these vectorized functions may assume len >= 256. */ - -static bool __attribute__((target("sse2"))) -buffer_zero_sse2(const void *buf, size_t len) -{ - /* Unaligned loads at head/tail. */ - __m128i v = *(__m128i_u *)(buf); - __m128i w = *(__m128i_u *)(buf + len - 16); - /* Align head/tail to 16-byte boundaries. */ - const __m128i *p = QEMU_ALIGN_PTR_DOWN(buf + 16, 16); - const __m128i *e = QEMU_ALIGN_PTR_DOWN(buf + len - 1, 16); - __m128i zero = { 0 }; - - /* Collect a partial block at tail end. */ - v |= e[-1]; w |= e[-2]; - SSE_REASSOC_BARRIER(v, w); - v |= e[-3]; w |= e[-4]; - SSE_REASSOC_BARRIER(v, w); - v |= e[-5]; w |= e[-6]; - SSE_REASSOC_BARRIER(v, w); - v |= e[-7]; v |= w; - - /* - * Loop over complete 128-byte blocks. - * With the head and tail removed, e - p >= 14, so the loop - * must iterate at least once. - */ - do { - v = _mm_cmpeq_epi8(v, zero); - if (unlikely(_mm_movemask_epi8(v) != 0xFFFF)) { - return false; - } - v = p[0]; w = p[1]; - SSE_REASSOC_BARRIER(v, w); - v |= p[2]; w |= p[3]; - SSE_REASSOC_BARRIER(v, w); - v |= p[4]; w |= p[5]; - SSE_REASSOC_BARRIER(v, w); - v |= p[6]; w |= p[7]; - SSE_REASSOC_BARRIER(v, w); - v |= w; - p += 8; - } while (p < e - 7); - - return _mm_movemask_epi8(_mm_cmpeq_epi8(v, zero)) == 0xFFFF; -} - -#ifdef CONFIG_AVX2_OPT -static bool __attribute__((target("avx2"))) -buffer_zero_avx2(const void *buf, size_t len) -{ - /* Unaligned loads at head/tail. */ - __m256i v = *(__m256i_u *)(buf); - __m256i w = *(__m256i_u *)(buf + len - 32); - /* Align head/tail to 32-byte boundaries. */ - const __m256i *p = QEMU_ALIGN_PTR_DOWN(buf + 32, 32); - const __m256i *e = QEMU_ALIGN_PTR_DOWN(buf + len - 1, 32); - __m256i zero = { 0 }; - - /* Collect a partial block at tail end. */ - v |= e[-1]; w |= e[-2]; - SSE_REASSOC_BARRIER(v, w); - v |= e[-3]; w |= e[-4]; - SSE_REASSOC_BARRIER(v, w); - v |= e[-5]; w |= e[-6]; - SSE_REASSOC_BARRIER(v, w); - v |= e[-7]; v |= w; - - /* Loop over complete 256-byte blocks. */ - for (; p < e - 7; p += 8) { - /* PTEST is not profitable here. */ - v = _mm256_cmpeq_epi8(v, zero); - if (unlikely(_mm256_movemask_epi8(v) != 0xFFFFFFFF)) { - return false; - } - v = p[0]; w = p[1]; - SSE_REASSOC_BARRIER(v, w); - v |= p[2]; w |= p[3]; - SSE_REASSOC_BARRIER(v, w); - v |= p[4]; w |= p[5]; - SSE_REASSOC_BARRIER(v, w); - v |= p[6]; w |= p[7]; - SSE_REASSOC_BARRIER(v, w); - v |= w; - } - - return _mm256_movemask_epi8(_mm256_cmpeq_epi8(v, zero)) == 0xFFFFFFFF; -} -#endif /* CONFIG_AVX2_OPT */ - -static biz_accel_fn const accel_table[] = { - buffer_is_zero_int_ge256, - buffer_zero_sse2, -#ifdef CONFIG_AVX2_OPT - buffer_zero_avx2, -#endif -}; - -static unsigned best_accel(void) -{ -#ifdef CONFIG_AVX2_OPT - unsigned info = cpuinfo_init(); - - if (info & CPUINFO_AVX2) { - return 2; - } -#endif - return 1; -} - -#elif defined(__aarch64__) && defined(__ARM_NEON) -#include <arm_neon.h> - -/* - * Helper for preventing the compiler from reassociating - * chains of binary vector operations. - */ -#define REASSOC_BARRIER(vec0, vec1) asm("" : "+w"(vec0), "+w"(vec1)) - -static bool buffer_is_zero_simd(const void *buf, size_t len) -{ - uint32x4_t t0, t1, t2, t3; - - /* Align head/tail to 16-byte boundaries. */ - const uint32x4_t *p = QEMU_ALIGN_PTR_DOWN(buf + 16, 16); - const uint32x4_t *e = QEMU_ALIGN_PTR_DOWN(buf + len - 1, 16); - - /* Unaligned loads at head/tail. */ - t0 = vld1q_u32(buf) | vld1q_u32(buf + len - 16); - - /* Collect a partial block at tail end. */ - t1 = e[-7] | e[-6]; - t2 = e[-5] | e[-4]; - t3 = e[-3] | e[-2]; - t0 |= e[-1]; - REASSOC_BARRIER(t0, t1); - REASSOC_BARRIER(t2, t3); - t0 |= t1; - t2 |= t3; - REASSOC_BARRIER(t0, t2); - t0 |= t2; - - /* - * Loop over complete 128-byte blocks. - * With the head and tail removed, e - p >= 14, so the loop - * must iterate at least once. - */ - do { - /* - * Reduce via UMAXV. Whatever the actual result, - * it will only be zero if all input bytes are zero. - */ - if (unlikely(vmaxvq_u32(t0) != 0)) { - return false; - } - - t0 = p[0] | p[1]; - t1 = p[2] | p[3]; - t2 = p[4] | p[5]; - t3 = p[6] | p[7]; - REASSOC_BARRIER(t0, t1); - REASSOC_BARRIER(t2, t3); - t0 |= t1; - t2 |= t3; - REASSOC_BARRIER(t0, t2); - t0 |= t2; - p += 8; - } while (p < e - 7); - - return vmaxvq_u32(t0) == 0; -} - -#define best_accel() 1 -static biz_accel_fn const accel_table[] = { - buffer_is_zero_int_ge256, - buffer_is_zero_simd, -}; -#else -#define best_accel() 0 -static biz_accel_fn const accel_table[1] = { - buffer_is_zero_int_ge256 -}; -#endif +#include "host/bufferiszero.c.inc" static biz_accel_fn buffer_is_zero_accel; static unsigned accel_index; diff --git a/util/cpuinfo-loongarch.c b/util/cpuinfo-loongarch.c index 08b6d74..bb1f7f6 100644 --- a/util/cpuinfo-loongarch.c +++ b/util/cpuinfo-loongarch.c @@ -29,6 +29,7 @@ unsigned __attribute__((constructor)) cpuinfo_init(void) info = CPUINFO_ALWAYS; info |= (hwcap & HWCAP_LOONGARCH_LSX ? CPUINFO_LSX : 0); + info |= (hwcap & HWCAP_LOONGARCH_LASX ? CPUINFO_LASX : 0); cpuinfo = info; return info; |