[X86] Implement the fusing of MUL+SUBADD to FMSUBADD

This patch turns shuffles of fadd/fsub with fmul into fmsubadd.

Patch by Dmitry Venikov

Differential Revision: https://reviews.llvm.org/D40335

llvm-svn: 321200
diff --git a/llvm/test/CodeGen/X86/fmsubadd-combine.ll b/llvm/test/CodeGen/X86/fmsubadd-combine.ll
index 814d61e..ca2c61a 100644
--- a/llvm/test/CodeGen/X86/fmsubadd-combine.ll
+++ b/llvm/test/CodeGen/X86/fmsubadd-combine.ll
@@ -8,26 +8,17 @@
 define <2 x double> @mul_subadd_pd128(<2 x double> %A, <2 x double> %B, <2 x double> %C) #0 {
 ; FMA3_256-LABEL: mul_subadd_pd128:
 ; FMA3_256:       # %bb.0: # %entry
-; FMA3_256-NEXT:    vmulpd %xmm1, %xmm0, %xmm0
-; FMA3_256-NEXT:    vsubpd %xmm2, %xmm0, %xmm1
-; FMA3_256-NEXT:    vaddpd %xmm2, %xmm0, %xmm0
-; FMA3_256-NEXT:    vblendpd {{.*#+}} xmm0 = xmm0[0],xmm1[1]
+; FMA3_256-NEXT:    vfmsubadd213pd %xmm2, %xmm1, %xmm0
 ; FMA3_256-NEXT:    retq
 ;
 ; FMA3_512-LABEL: mul_subadd_pd128:
 ; FMA3_512:       # %bb.0: # %entry
-; FMA3_512-NEXT:    vmulpd %xmm1, %xmm0, %xmm0
-; FMA3_512-NEXT:    vsubpd %xmm2, %xmm0, %xmm1
-; FMA3_512-NEXT:    vaddpd %xmm2, %xmm0, %xmm0
-; FMA3_512-NEXT:    vmovsd {{.*#+}} xmm0 = xmm0[0],xmm1[1]
+; FMA3_512-NEXT:    vfmsubadd213pd %xmm2, %xmm1, %xmm0
 ; FMA3_512-NEXT:    retq
 ;
 ; FMA4-LABEL: mul_subadd_pd128:
 ; FMA4:       # %bb.0: # %entry
-; FMA4-NEXT:    vmulpd %xmm1, %xmm0, %xmm0
-; FMA4-NEXT:    vsubpd %xmm2, %xmm0, %xmm1
-; FMA4-NEXT:    vaddpd %xmm2, %xmm0, %xmm0
-; FMA4-NEXT:    vblendpd {{.*#+}} xmm0 = xmm0[0],xmm1[1]
+; FMA4-NEXT:    vfmsubaddpd %xmm2, %xmm1, %xmm0, %xmm0
 ; FMA4-NEXT:    retq
 entry:
   %AB = fmul <2 x double> %A, %B
@@ -40,18 +31,12 @@
 define <4 x float> @mul_subadd_ps128(<4 x float> %A, <4 x float> %B, <4 x float> %C) #0 {
 ; FMA3-LABEL: mul_subadd_ps128:
 ; FMA3:       # %bb.0: # %entry
-; FMA3-NEXT:    vmulps %xmm1, %xmm0, %xmm0
-; FMA3-NEXT:    vsubps %xmm2, %xmm0, %xmm1
-; FMA3-NEXT:    vaddps %xmm2, %xmm0, %xmm0
-; FMA3-NEXT:    vblendps {{.*#+}} xmm0 = xmm0[0],xmm1[1],xmm0[2],xmm1[3]
+; FMA3-NEXT:    vfmsubadd213ps  %xmm2, %xmm1, %xmm0
 ; FMA3-NEXT:    retq
 ;
 ; FMA4-LABEL: mul_subadd_ps128:
 ; FMA4:       # %bb.0: # %entry
-; FMA4-NEXT:    vmulps %xmm1, %xmm0, %xmm0
-; FMA4-NEXT:    vsubps %xmm2, %xmm0, %xmm1
-; FMA4-NEXT:    vaddps %xmm2, %xmm0, %xmm0
-; FMA4-NEXT:    vblendps {{.*#+}} xmm0 = xmm0[0],xmm1[1],xmm0[2],xmm1[3]
+; FMA4-NEXT:    vfmsubaddps %xmm2, %xmm1, %xmm0, %xmm0
 ; FMA4-NEXT:    retq
 entry:
   %AB = fmul <4 x float> %A, %B
@@ -64,18 +49,12 @@
 define <4 x double> @mul_subadd_pd256(<4 x double> %A, <4 x double> %B, <4 x double> %C) #0 {
 ; FMA3-LABEL: mul_subadd_pd256:
 ; FMA3:       # %bb.0: # %entry
-; FMA3-NEXT:    vmulpd %ymm1, %ymm0, %ymm0
-; FMA3-NEXT:    vsubpd %ymm2, %ymm0, %ymm1
-; FMA3-NEXT:    vaddpd %ymm2, %ymm0, %ymm0
-; FMA3-NEXT:    vblendpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3]
+; FMA3-NEXT:    vfmsubadd213pd  %ymm2, %ymm1, %ymm0
 ; FMA3-NEXT:    retq
 ;
 ; FMA4-LABEL: mul_subadd_pd256:
 ; FMA4:       # %bb.0: # %entry
-; FMA4-NEXT:    vmulpd %ymm1, %ymm0, %ymm0
-; FMA4-NEXT:    vsubpd %ymm2, %ymm0, %ymm1
-; FMA4-NEXT:    vaddpd %ymm2, %ymm0, %ymm0
-; FMA4-NEXT:    vblendpd {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3]
+; FMA4-NEXT:    vfmsubaddpd %ymm2, %ymm1, %ymm0, %ymm0
 ; FMA4-NEXT:    retq
 entry:
   %AB = fmul <4 x double> %A, %B
@@ -88,18 +67,12 @@
 define <8 x float> @mul_subadd_ps256(<8 x float> %A, <8 x float> %B, <8 x float> %C) #0 {
 ; FMA3-LABEL: mul_subadd_ps256:
 ; FMA3:       # %bb.0: # %entry
-; FMA3-NEXT:    vmulps %ymm1, %ymm0, %ymm0
-; FMA3-NEXT:    vsubps %ymm2, %ymm0, %ymm1
-; FMA3-NEXT:    vaddps %ymm2, %ymm0, %ymm0
-; FMA3-NEXT:    vblendps {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3],ymm0[4],ymm1[5],ymm0[6],ymm1[7]
+; FMA3-NEXT:    vfmsubadd213ps  %ymm2, %ymm1, %ymm0
 ; FMA3-NEXT:    retq
 ;
 ; FMA4-LABEL: mul_subadd_ps256:
 ; FMA4:       # %bb.0: # %entry
-; FMA4-NEXT:    vmulps %ymm1, %ymm0, %ymm0
-; FMA4-NEXT:    vsubps %ymm2, %ymm0, %ymm1
-; FMA4-NEXT:    vaddps %ymm2, %ymm0, %ymm0
-; FMA4-NEXT:    vblendps {{.*#+}} ymm0 = ymm0[0],ymm1[1],ymm0[2],ymm1[3],ymm0[4],ymm1[5],ymm0[6],ymm1[7]
+; FMA4-NEXT:    vfmsubaddps %ymm2, %ymm1, %ymm0, %ymm0
 ; FMA4-NEXT:    retq
 entry:
   %AB = fmul <8 x float> %A, %B
@@ -112,34 +85,19 @@
 define <8 x double> @mul_subadd_pd512(<8 x double> %A, <8 x double> %B, <8 x double> %C) #0 {
 ; FMA3_256-LABEL: mul_subadd_pd512:
 ; FMA3_256:       # %bb.0: # %entry
-; FMA3_256-NEXT:    vmulpd %ymm2, %ymm0, %ymm0
-; FMA3_256-NEXT:    vmulpd %ymm3, %ymm1, %ymm1
-; FMA3_256-NEXT:    vsubpd %ymm5, %ymm1, %ymm2
-; FMA3_256-NEXT:    vsubpd %ymm4, %ymm0, %ymm3
-; FMA3_256-NEXT:    vaddpd %ymm5, %ymm1, %ymm1
-; FMA3_256-NEXT:    vblendpd {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3]
-; FMA3_256-NEXT:    vaddpd %ymm4, %ymm0, %ymm0
-; FMA3_256-NEXT:    vblendpd {{.*#+}} ymm0 = ymm0[0],ymm3[1],ymm0[2],ymm3[3]
+; FMA3_256-NEXT:    vfmsubadd213pd  %ymm4, %ymm2, %ymm0
+; FMA3_256-NEXT:    vfmsubadd213pd  %ymm5, %ymm3, %ymm1
 ; FMA3_256-NEXT:    retq
 ;
 ; FMA3_512-LABEL: mul_subadd_pd512:
 ; FMA3_512:       # %bb.0: # %entry
-; FMA3_512-NEXT:    vmulpd %zmm1, %zmm0, %zmm0
-; FMA3_512-NEXT:    vsubpd %zmm2, %zmm0, %zmm1
-; FMA3_512-NEXT:    vaddpd %zmm2, %zmm0, %zmm0
-; FMA3_512-NEXT:    vshufpd {{.*#+}} zmm0 = zmm0[0],zmm1[1],zmm0[2],zmm1[3],zmm0[4],zmm1[5],zmm0[6],zmm1[7]
+; FMA3_512-NEXT:    vfmsubadd213pd  %zmm2, %zmm1, %zmm0
 ; FMA3_512-NEXT:    retq
 ;
 ; FMA4-LABEL: mul_subadd_pd512:
 ; FMA4:       # %bb.0: # %entry
-; FMA4-NEXT:    vmulpd %ymm2, %ymm0, %ymm0
-; FMA4-NEXT:    vmulpd %ymm3, %ymm1, %ymm1
-; FMA4-NEXT:    vsubpd %ymm5, %ymm1, %ymm2
-; FMA4-NEXT:    vsubpd %ymm4, %ymm0, %ymm3
-; FMA4-NEXT:    vaddpd %ymm5, %ymm1, %ymm1
-; FMA4-NEXT:    vblendpd {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3]
-; FMA4-NEXT:    vaddpd %ymm4, %ymm0, %ymm0
-; FMA4-NEXT:    vblendpd {{.*#+}} ymm0 = ymm0[0],ymm3[1],ymm0[2],ymm3[3]
+; FMA4-NEXT:    vfmsubaddpd %ymm4, %ymm2, %ymm0, %ymm0
+; FMA4-NEXT:    vfmsubaddpd %ymm5, %ymm3, %ymm1, %ymm1
 ; FMA4-NEXT:    retq
 entry:
   %AB = fmul <8 x double> %A, %B
@@ -152,35 +110,19 @@
 define <16 x float> @mul_subadd_ps512(<16 x float> %A, <16 x float> %B, <16 x float> %C) #0 {
 ; FMA3_256-LABEL: mul_subadd_ps512:
 ; FMA3_256:       # %bb.0: # %entry
-; FMA3_256-NEXT:    vmulps %ymm2, %ymm0, %ymm0
-; FMA3_256-NEXT:    vmulps %ymm3, %ymm1, %ymm1
-; FMA3_256-NEXT:    vsubps %ymm5, %ymm1, %ymm2
-; FMA3_256-NEXT:    vsubps %ymm4, %ymm0, %ymm3
-; FMA3_256-NEXT:    vaddps %ymm5, %ymm1, %ymm1
-; FMA3_256-NEXT:    vblendps {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3],ymm1[4],ymm2[5],ymm1[6],ymm2[7]
-; FMA3_256-NEXT:    vaddps %ymm4, %ymm0, %ymm0
-; FMA3_256-NEXT:    vblendps {{.*#+}} ymm0 = ymm0[0],ymm3[1],ymm0[2],ymm3[3],ymm0[4],ymm3[5],ymm0[6],ymm3[7]
+; FMA3_256-NEXT:    vfmsubadd213ps  %ymm4, %ymm2, %ymm0
+; FMA3_256-NEXT:    vfmsubadd213ps  %ymm5, %ymm3, %ymm1
 ; FMA3_256-NEXT:    retq
 ;
 ; FMA3_512-LABEL: mul_subadd_ps512:
 ; FMA3_512:       # %bb.0: # %entry
-; FMA3_512-NEXT:    vmulps %zmm1, %zmm0, %zmm1
-; FMA3_512-NEXT:    vaddps %zmm2, %zmm1, %zmm0
-; FMA3_512-NEXT:    movw $-21846, %ax # imm = 0xAAAA
-; FMA3_512-NEXT:    kmovw %eax, %k1
-; FMA3_512-NEXT:    vsubps %zmm2, %zmm1, %zmm0 {%k1}
+; FMA3_512-NEXT:    vfmsubadd213ps  %zmm2, %zmm1, %zmm0
 ; FMA3_512-NEXT:    retq
 ;
 ; FMA4-LABEL: mul_subadd_ps512:
 ; FMA4:       # %bb.0: # %entry
-; FMA4-NEXT:    vmulps %ymm2, %ymm0, %ymm0
-; FMA4-NEXT:    vmulps %ymm3, %ymm1, %ymm1
-; FMA4-NEXT:    vsubps %ymm5, %ymm1, %ymm2
-; FMA4-NEXT:    vsubps %ymm4, %ymm0, %ymm3
-; FMA4-NEXT:    vaddps %ymm5, %ymm1, %ymm1
-; FMA4-NEXT:    vblendps {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3],ymm1[4],ymm2[5],ymm1[6],ymm2[7]
-; FMA4-NEXT:    vaddps %ymm4, %ymm0, %ymm0
-; FMA4-NEXT:    vblendps {{.*#+}} ymm0 = ymm0[0],ymm3[1],ymm0[2],ymm3[3],ymm0[4],ymm3[5],ymm0[6],ymm3[7]
+; FMA4-NEXT:    vfmsubaddps %ymm4, %ymm2, %ymm0, %ymm0
+; FMA4-NEXT:    vfmsubaddps %ymm5, %ymm3, %ymm1, %ymm1
 ; FMA4-NEXT:    retq
 entry:
   %AB = fmul <16 x float> %A, %B