大量の計算を常に行うような場合、C言語の速度をさらに上げるには、CPUのSIMD命令に置き換えられる組み込み関数を使う方法がある。 ただし、これもvDSPと同じで量が多くまた見やすい一覧がないので作ってみる。 なお、独断と偏見で使いそうもないものは一覧に載せていない。
__m128 _mm_load_ss(float * p) r0 := *p r1 := 0 r2 := 0 r3 := 0
__m128 _mm_load1_ps(float * p) r0 := *p r1 := *p r2 := *p r3 := *p
__m128 _mm_load_ps(float * p) r0 := p[0] r1 := p[1] r2 := p[2] r2 := p[3] The address must be 16-byte aligned
__m128 _mm_loadu_ps(float* p) r0 := p[0] r1 := p[1] r2 := p[2] r3 := p[3] The address does not need to be 16-byte aligned
__m128 _mm_loadr_ps(float* p) r0 := p[3] r1 := p[2] r2 := p[1] r3 := p[0] The address must be 16-byte aligned
__m128 _mm_set_ss(float w) r0 := w r1 := 0 r2 := 0 r3 := 0
__m128 _mm_set1_ps(float w) r0 := w r1 := w r2 := w r3 := w
__m128 _mm_set_ps(float z, float y, float x, float w) r0 := w r1 := x r2 := y r3 := z
__m128 _mm_setr_ps(float z, float y, float x, float w) r0 := z r1 := y r2 := x r3 := w
__m128 _mm_setzero_ps(void) r0 := 0 r1 := 0 r2 := 0 r3 := 0
void _mm_store_ss(float * p, __m128 a) *p := a0
void _mm_store1_ps(float * p, __m128 a) p[0] := a0 p[1] := a0 p[2] := a0 p[3] := a0
void _mm_store_ps(float *p, __m128 a) p[0] := a0 p[1] := a1 p[2] := a2 p[3] := a3 The address must be 16-byte aligned
void _mm_storeu_ps(float *p, __m128 a) p[0] := a0 p[1] := a1 p[2] := a2 p[3] := a3 The address does not need to be 16-byte aligned
void _mm_storer_ps(float * p, __m128 a) p[0] := a3 p[1] := a2 p[2] := a1 p[3] := a0 The address must be 16-byte aligned
__m128 _mm_move_ss(__m128 a, __m128 b) r0 := b0 r1 := a1 r2 := a2 r3 := a3
__m128 _mm_add_ss(__m128 a, __m128 b) r0 := a0 + b0 r1 := a1 r2 := a2 r3 := a3
__m128 _mm_add_ps(__m128 a, __m128 b) r0 := a0 + b0 r1 := a1 + b1 r2 := a2 + b2 r3 := a3 + b3
__m128 _mm_sub_ss(__m128 a, __m128 b)
__m128 _mm_sub_ps(__m128 a, __m128 b)
__m128 _mm_mul_ss(__m128 a, __m128 b)
__m128 _mm_mul_ps(__m128 a, __m128 b)
__m128 _mm_div_ss(__m128 a, __m128 b)
__m128 _mm_div_ps(__m128 a, __m128 b)
__m128 _mm_sqrt_ss(__m128 a, __m128 b) ルート
__m128 _mm_sqrt_ps(__m128 a, __m128 b) ルート
__m128 _mm_rcp_ss(__m128 a, __m128 b) 逆数
__m128 _mm_rcp_ps(__m128 a, __m128 b) 逆数
__m128 _mm_rsqrt_ss(__m128 a, __m128 b) ルートを取ってから逆数
__m128 _mm_rsqrt_ps(__m128 a, __m128 b) ルートを取ってから逆数
__m128 _mm_min_ss(__m128 a, __m128 b)
__m128 _mm_min_ps(__m128 a, __m128 b)
__m128 _mm_max_ss(__m128 a, __m128 b)
__m128 _mm_max_ps(__m128 a, __m128 b)
__m128 _mm_shuffle_ps(__m128 a, __m128 b, int i)
_MM_SHUFFLE(z, y, x, w) (z<<6) | (y<<4) | (x<<2) | w
例
a[0] = 0;
a[1] = 1;
a[2] = 2;
a[3] = 3;
b[0] = 4;
b[1] = 5;
b[2] = 6;
b[3] = 7;
__m128 m1 = _mm_loadu_ps(a);
__m128 m2 = _mm_loadu_ps(b);
__m128 m3 = _mm_shuffle_ps(m1, m2, _MM_SHUFFLE(3, 2, 1, 0));
_mm_storeu_ps(c, m3);
printf("c[0] %f c[1] %f c[2] %f c[3] %f", c[0], c[1], c[2], c[3]);
c[0] 0.0 c[1] 1.0 c[2] 6.0 c[3] 7.0
_MM_SHUFFLEの第3,4引数がm1から選択するもの、第1,2引数がm2から選択するもの
__m128 m3 = _mm_shuffle_ps(m1, m2, _MM_SHUFFLE(1, 1, 1, 1));
c[0] 1.0 c[1] 1.0 c[2] 5.0 c[3] 5.0
__m128 _mm_unpackhi_ps(__m128 a, __m128 b)
r0 := a2
r1 := b2
r2 := a3
r3 := b3
__m128 _mm_unpacklo_ps(__m128 a, __m128 b)
r0 := a0
r1 := b0
r2 := a1
r3 := b1
__m128 _mm_movehl_ps(__m128 a, __m128 b)
r3 := a3
r2 := a2
r1 := b3
r0 := b2
__m128 _mm_movelh_ps(__m128 a, __m128 b)
r3 := b1
r2 := b0
r1 := a1
r0 := a0
int _mm_movemask_ps(__m128 a) r := sign(a3)<<3 | sign(a2)<<2 | sign(a1)<<1 | sign(a0)
__m128 _mm_and_ps(__m128 a , __m128 b ) r0 := a0 & b0 r1 := a1 & b1 r2 := a2 & b2 r3 := a3 & b3
__m128 _mm_andnot_ps(__m128 a , __m128 b ) r0 := ~a0 & b0 r1 := ~a1 & b1 r2 := ~a2 & b2 r3 := ~a3 & b3
__m128 _mm_or_ps(__m128 a , __m128 b ) r0 := a0 | b0 r1 := a1 | b1 r2 := a2 | b2 r3 := a3 | b3
__m128 _mm_xor_ps(__m128 a , __m128 b ) r0 := a0 ^ b0 r1 := a1 ^ b1 r2 := a2 ^ b2 r3 := a3 ^ b3
__m128 _mm_blend_ps( __m128 a, __m128 b, const int mask )
r0 := (mask0 == 0) ? a0 : b0
r1 := (mask1 == 0) ? a1 : b1
r2 := (mask2 == 0) ? a2 : b2
r3 := (mask3 == 0) ? a3 : b3
__m128 _mm_blendv_ps( __m128 a, __m128 b, __m128 mask )
r0 := (mask0 & 0x80000000) ? b0 : a0
r1 := (mask1 & 0x80000000) ? b1 : a1
r2 := (mask2 & 0x80000000) ? b2 : a2
r3 := (mask3 & 0x80000000) ? b3 : a3
int _mm_extract_ps( __m128 a, const int ndx )
r := (ndx == 0) ? a0 : ((ndx == 1) ? a1 : ((ndx == 2) ? a2 : a3))
__m128 _mm_hadd_ps( __m128 a, __m128 b )
The result of the operation on operand a (A3, A2, A1, A0) and operand b (B3, B2, B1, B0) is (B3 + B2, B1 + B0, A3 + A2, A1 + A0).
__m128 _mm_hsub_ps( __m128 a, __m128 b )
void _mm_prefetch(char * p , int i )
Loads one cache line of data from address p to a location closer to the processor.
The value i specifies the type of prefetch operation: the constants _MM_HINT_T0, _MM_HINT_T1, _MM_HINT_T2, and _MM_HINT_NTA, corresponding to the type of prefetch instruction, should be used
void _mm_stream_ps(float * p , __m128 a )
Stores the data in a to the address p without polluting the caches.
The address must be 16-byte aligned.
void _mm_sfence(void)
Guarantees that every preceding store is globally visible before any subsequent store.
SSE2 : SSE の doubleバージョン
__m128 : float(32bit) * 4
__m128d : double(64bit) * 2
__m128i : 整数 shortなら * 8
AVX :
2011 : Sandy Bridge
2012 : Ivy Bridge
2013 : Haswell
2014 : Broadwell
2015 : Skylake
2016 : Kaby Lake
2017 : Cannonlake
FMA(Fused Multiply Add) Haswell : 2013
AVX-512 : 2013
SSE Pentium 3 以降
SSE2 Pentium 4 以降
SSE4.1 Core 2 のPenyryn 以降
SSE4.2 Nehalem 以降
Intel Core 2 processor family
for Laptop
Merom dual (65 nm) July 2006
Penryn dual (45 nm) January 2008
