[llvm] r347149 - [X86] Don't use a pmaddwd for vXi32 multiply if the inputs are zero extends from i8 or smaller without SSE4.1. Prefer to shrink the mul instead.
Craig Topper via llvm-commits
llvm-commits at lists.llvm.org
Sat Nov 17 21:53:21 PST 2018
Author: ctopper
Date: Sat Nov 17 21:53:21 2018
New Revision: 347149
URL: http://llvm.org/viewvc/llvm-project?rev=347149&view=rev
Log:
[X86] Don't use a pmaddwd for vXi32 multiply if the inputs are zero extends from i8 or smaller without SSE4.1. Prefer to shrink the mul instead.
The zero extend will require two stages of unpacks to implement. So its better to shrink the multiply using pmullw and then extend that result back to v4i32 using a single unpack.
Modified:
llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
llvm/trunk/test/CodeGen/X86/shrink_vmul-widen.ll
llvm/trunk/test/CodeGen/X86/shrink_vmul.ll
Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=347149&r1=347148&r2=347149&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Sat Nov 17 21:53:21 2018
@@ -34678,6 +34678,16 @@ static SDValue combineMulToPMADDWD(SDNod
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
+
+ // If we are zero extending two steps without SSE4.1, its better to reduce
+ // the vmul width instead.
+ if (!Subtarget.hasSSE41() &&
+ (N0.getOpcode() == ISD::ZERO_EXTEND &&
+ N0.getOperand(0).getScalarValueSizeInBits() <= 8) &&
+ (N1.getOpcode() == ISD::ZERO_EXTEND &&
+ N1.getOperand(0).getScalarValueSizeInBits() <= 8))
+ return SDValue();
+
APInt Mask17 = APInt::getHighBitsSet(32, 17);
if (!DAG.MaskedValueIsZero(N1, Mask17) ||
!DAG.MaskedValueIsZero(N0, Mask17))
Modified: llvm/trunk/test/CodeGen/X86/shrink_vmul-widen.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/shrink_vmul-widen.ll?rev=347149&r1=347148&r2=347149&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/shrink_vmul-widen.ll (original)
+++ llvm/trunk/test/CodeGen/X86/shrink_vmul-widen.ll Sat Nov 17 21:53:21 2018
@@ -24,15 +24,14 @@ define void @mul_2xi8(i8* nocapture read
; X86-SSE-NEXT: movl c, %esi
; X86-SSE-NEXT: movzwl (%edx,%ecx), %edx
; X86-SSE-NEXT: movd %edx, %xmm0
-; X86-SSE-NEXT: pxor %xmm1, %xmm1
-; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
-; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3]
; X86-SSE-NEXT: movzwl (%eax,%ecx), %eax
-; X86-SSE-NEXT: movd %eax, %xmm2
-; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3],xmm2[4],xmm1[4],xmm2[5],xmm1[5],xmm2[6],xmm1[6],xmm2[7],xmm1[7]
-; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3]
-; X86-SSE-NEXT: pmaddwd %xmm0, %xmm2
-; X86-SSE-NEXT: movq %xmm2, (%esi,%ecx,4)
+; X86-SSE-NEXT: movd %eax, %xmm1
+; X86-SSE-NEXT: pxor %xmm2, %xmm2
+; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm2[0],xmm0[1],xmm2[1],xmm0[2],xmm2[2],xmm0[3],xmm2[3],xmm0[4],xmm2[4],xmm0[5],xmm2[5],xmm0[6],xmm2[6],xmm0[7],xmm2[7]
+; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
+; X86-SSE-NEXT: pmullw %xmm0, %xmm1
+; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
+; X86-SSE-NEXT: movq %xmm1, (%esi,%ecx,4)
; X86-SSE-NEXT: popl %esi
; X86-SSE-NEXT: retl
;
@@ -59,15 +58,14 @@ define void @mul_2xi8(i8* nocapture read
; X64-SSE-NEXT: movq {{.*}}(%rip), %rax
; X64-SSE-NEXT: movzwl (%rdi,%rdx), %ecx
; X64-SSE-NEXT: movd %ecx, %xmm0
-; X64-SSE-NEXT: pxor %xmm1, %xmm1
-; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
-; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3]
; X64-SSE-NEXT: movzwl (%rsi,%rdx), %ecx
-; X64-SSE-NEXT: movd %ecx, %xmm2
-; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3],xmm2[4],xmm1[4],xmm2[5],xmm1[5],xmm2[6],xmm1[6],xmm2[7],xmm1[7]
-; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3]
-; X64-SSE-NEXT: pmaddwd %xmm0, %xmm2
-; X64-SSE-NEXT: movq %xmm2, (%rax,%rdx,4)
+; X64-SSE-NEXT: movd %ecx, %xmm1
+; X64-SSE-NEXT: pxor %xmm2, %xmm2
+; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm2[0],xmm0[1],xmm2[1],xmm0[2],xmm2[2],xmm0[3],xmm2[3],xmm0[4],xmm2[4],xmm0[5],xmm2[5],xmm0[6],xmm2[6],xmm0[7],xmm2[7]
+; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
+; X64-SSE-NEXT: pmullw %xmm0, %xmm1
+; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
+; X64-SSE-NEXT: movq %xmm1, (%rax,%rdx,4)
; X64-SSE-NEXT: retq
;
; X64-AVX-LABEL: mul_2xi8:
@@ -114,14 +112,13 @@ define void @mul_4xi8(i8* nocapture read
; X86-SSE-NEXT: movl {{[0-9]+}}(%esp), %edx
; X86-SSE-NEXT: movl c, %esi
; X86-SSE-NEXT: movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
-; X86-SSE-NEXT: pxor %xmm1, %xmm1
-; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
-; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3]
-; X86-SSE-NEXT: movd {{.*#+}} xmm2 = mem[0],zero,zero,zero
-; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3],xmm2[4],xmm1[4],xmm2[5],xmm1[5],xmm2[6],xmm1[6],xmm2[7],xmm1[7]
-; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3]
-; X86-SSE-NEXT: pmaddwd %xmm0, %xmm2
-; X86-SSE-NEXT: movdqu %xmm2, (%esi,%ecx,4)
+; X86-SSE-NEXT: movd {{.*#+}} xmm1 = mem[0],zero,zero,zero
+; X86-SSE-NEXT: pxor %xmm2, %xmm2
+; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm2[0],xmm0[1],xmm2[1],xmm0[2],xmm2[2],xmm0[3],xmm2[3],xmm0[4],xmm2[4],xmm0[5],xmm2[5],xmm0[6],xmm2[6],xmm0[7],xmm2[7]
+; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
+; X86-SSE-NEXT: pmullw %xmm0, %xmm1
+; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
+; X86-SSE-NEXT: movdqu %xmm1, (%esi,%ecx,4)
; X86-SSE-NEXT: popl %esi
; X86-SSE-NEXT: retl
;
@@ -143,14 +140,13 @@ define void @mul_4xi8(i8* nocapture read
; X64-SSE: # %bb.0: # %entry
; X64-SSE-NEXT: movq {{.*}}(%rip), %rax
; X64-SSE-NEXT: movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
-; X64-SSE-NEXT: pxor %xmm1, %xmm1
-; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
-; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3]
-; X64-SSE-NEXT: movd {{.*#+}} xmm2 = mem[0],zero,zero,zero
-; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3],xmm2[4],xmm1[4],xmm2[5],xmm1[5],xmm2[6],xmm1[6],xmm2[7],xmm1[7]
-; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3]
-; X64-SSE-NEXT: pmaddwd %xmm0, %xmm2
-; X64-SSE-NEXT: movdqu %xmm2, (%rax,%rdx,4)
+; X64-SSE-NEXT: movd {{.*#+}} xmm1 = mem[0],zero,zero,zero
+; X64-SSE-NEXT: pxor %xmm2, %xmm2
+; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm2[0],xmm0[1],xmm2[1],xmm0[2],xmm2[2],xmm0[3],xmm2[3],xmm0[4],xmm2[4],xmm0[5],xmm2[5],xmm0[6],xmm2[6],xmm0[7],xmm2[7]
+; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
+; X64-SSE-NEXT: pmullw %xmm0, %xmm1
+; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
+; X64-SSE-NEXT: movdqu %xmm1, (%rax,%rdx,4)
; X64-SSE-NEXT: retq
;
; X64-AVX-LABEL: mul_4xi8:
Modified: llvm/trunk/test/CodeGen/X86/shrink_vmul.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/shrink_vmul.ll?rev=347149&r1=347148&r2=347149&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/shrink_vmul.ll (original)
+++ llvm/trunk/test/CodeGen/X86/shrink_vmul.ll Sat Nov 17 21:53:21 2018
@@ -106,14 +106,13 @@ define void @mul_4xi8(i8* nocapture read
; X86-SSE-NEXT: movl {{[0-9]+}}(%esp), %edx
; X86-SSE-NEXT: movl c, %esi
; X86-SSE-NEXT: movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
-; X86-SSE-NEXT: pxor %xmm1, %xmm1
-; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
-; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3]
-; X86-SSE-NEXT: movd {{.*#+}} xmm2 = mem[0],zero,zero,zero
-; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3],xmm2[4],xmm1[4],xmm2[5],xmm1[5],xmm2[6],xmm1[6],xmm2[7],xmm1[7]
-; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3]
-; X86-SSE-NEXT: pmaddwd %xmm0, %xmm2
-; X86-SSE-NEXT: movdqu %xmm2, (%esi,%ecx,4)
+; X86-SSE-NEXT: movd {{.*#+}} xmm1 = mem[0],zero,zero,zero
+; X86-SSE-NEXT: pxor %xmm2, %xmm2
+; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm2[0],xmm0[1],xmm2[1],xmm0[2],xmm2[2],xmm0[3],xmm2[3],xmm0[4],xmm2[4],xmm0[5],xmm2[5],xmm0[6],xmm2[6],xmm0[7],xmm2[7]
+; X86-SSE-NEXT: punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
+; X86-SSE-NEXT: pmullw %xmm0, %xmm1
+; X86-SSE-NEXT: punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
+; X86-SSE-NEXT: movdqu %xmm1, (%esi,%ecx,4)
; X86-SSE-NEXT: popl %esi
; X86-SSE-NEXT: retl
;
@@ -135,14 +134,13 @@ define void @mul_4xi8(i8* nocapture read
; X64-SSE: # %bb.0: # %entry
; X64-SSE-NEXT: movq {{.*}}(%rip), %rax
; X64-SSE-NEXT: movd {{.*#+}} xmm0 = mem[0],zero,zero,zero
-; X64-SSE-NEXT: pxor %xmm1, %xmm1
-; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3],xmm0[4],xmm1[4],xmm0[5],xmm1[5],xmm0[6],xmm1[6],xmm0[7],xmm1[7]
-; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1],xmm0[2],xmm1[2],xmm0[3],xmm1[3]
-; X64-SSE-NEXT: movd {{.*#+}} xmm2 = mem[0],zero,zero,zero
-; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3],xmm2[4],xmm1[4],xmm2[5],xmm1[5],xmm2[6],xmm1[6],xmm2[7],xmm1[7]
-; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm2 = xmm2[0],xmm1[0],xmm2[1],xmm1[1],xmm2[2],xmm1[2],xmm2[3],xmm1[3]
-; X64-SSE-NEXT: pmaddwd %xmm0, %xmm2
-; X64-SSE-NEXT: movdqu %xmm2, (%rax,%rdx,4)
+; X64-SSE-NEXT: movd {{.*#+}} xmm1 = mem[0],zero,zero,zero
+; X64-SSE-NEXT: pxor %xmm2, %xmm2
+; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm0 = xmm0[0],xmm2[0],xmm0[1],xmm2[1],xmm0[2],xmm2[2],xmm0[3],xmm2[3],xmm0[4],xmm2[4],xmm0[5],xmm2[5],xmm0[6],xmm2[6],xmm0[7],xmm2[7]
+; X64-SSE-NEXT: punpcklbw {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3],xmm1[4],xmm2[4],xmm1[5],xmm2[5],xmm1[6],xmm2[6],xmm1[7],xmm2[7]
+; X64-SSE-NEXT: pmullw %xmm0, %xmm1
+; X64-SSE-NEXT: punpcklwd {{.*#+}} xmm1 = xmm1[0],xmm2[0],xmm1[1],xmm2[1],xmm1[2],xmm2[2],xmm1[3],xmm2[3]
+; X64-SSE-NEXT: movdqu %xmm1, (%rax,%rdx,4)
; X64-SSE-NEXT: retq
;
; X64-AVX-LABEL: mul_4xi8:
More information about the llvm-commits
mailing list