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KNC prefetch:

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- make L3 prefetch to hit L2$, instead of being nop.
- fix vector prefetch to use single intrinsic, instead of two (this is
  caused by bug in Composer 14.0 documentation).
This commit is contained in:
Dmitry Babokin
2014-10-14 20:24:16 +04:00
parent 741df13eb8
commit 3f24c8dedc
1 changed files with 4 additions and 10 deletions
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14
examples/intrinsics/knc.h
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@@ -2214,7 +2214,8 @@ static FORCEINLINE void __prefetch_read_uniform_2(const char *p) {
}
static FORCEINLINE void __prefetch_read_uniform_3(const char *p) {
// There is no L3$ on KNC, don't want to pollute L2$ unecessarily
// There is no L3$ on KNC, but we prefetch into L2$ instead.
_mm_prefetch(p, _MM_HINT_T1); // prefetch into L2$
}
static FORCEINLINE void __prefetch_read_uniform_nt(const char *p) {
@@ -2226,22 +2227,15 @@ static FORCEINLINE void __prefetch_read_uniform_nt(const char *p) {
static FORCEINLINE void __prefetch_read_varying_##CACHE_NUM##_native(uint8_t *base, uint32_t scale, \
__vec16_i32 offsets, __vec16_i1 mask) { \
_mm512_mask_prefetch_i32gather_ps (offsets, mask, base, scale, HINT); \
offsets = _mm512_permutevar_epi32(_mm512_set_16to16_pi(7,6,5,4,3,2,1,0,15,14,13,12,11,10,9,8), offsets);\
__vec16_i1 copy_mask = _mm512_kmov(mask); \
_mm512_kswapb(mask, copy_mask); \
_mm512_mask_prefetch_i32gather_ps (offsets, mask, base, scale, _MM_HINT_T0); \
} \
static FORCEINLINE void __prefetch_read_varying_##CACHE_NUM(__vec16_i64 addr, __vec16_i1 mask) {} \
PREFETCH_READ_VARYING(1, _MM_HINT_T0)
PREFETCH_READ_VARYING(2, _MM_HINT_T1)
// L3 prefetch is mapped to L2 cache
PREFETCH_READ_VARYING(3, _MM_HINT_T1)
PREFETCH_READ_VARYING(nt, _MM_HINT_T2)
static FORCEINLINE void __prefetch_read_varying_3_native(uint8_t *base, uint32_t scale,
__vec16_i32 offsets, __vec16_i1 mask) {}
static FORCEINLINE void __prefetch_read_varying_3(__vec16_i64 addr, __vec16_i1 mask) {}
///////////////////////////////////////////////////////////////////////////
// atomics
///////////////////////////////////////////////////////////////////////////