[llvm] d9ffd32 - [X86] combineCMP - attempt to simplify KSHIFTR mask element extractions when just comparing against zero (REAPPLIED)
Simon Pilgrim via llvm-commits
llvm-commits at lists.llvm.org
Sat Sep 2 09:48:44 PDT 2023
Author: Simon Pilgrim
Date: 2023-09-02T17:45:17+01:00
New Revision: d9ffd3219e3817c1818b14eb1c3d5e274d9e3df7
URL: https://github.com/llvm/llvm-project/commit/d9ffd3219e3817c1818b14eb1c3d5e274d9e3df7
DIFF: https://github.com/llvm/llvm-project/commit/d9ffd3219e3817c1818b14eb1c3d5e274d9e3df7.diff
LOG: [X86] combineCMP - attempt to simplify KSHIFTR mask element extractions when just comparing against zero (REAPPLIED)
We can just bitcast the pre-shifted mask as an integer and use TEST/BT directly.
Reapplied with fix for 239ab16ec121 which didn't set the comparison type correctly
Added:
Modified:
llvm/lib/Target/X86/X86ISelLowering.cpp
llvm/test/CodeGen/X86/avx512-insert-extract.ll
llvm/test/CodeGen/X86/movmsk-cmp.ll
llvm/test/CodeGen/X86/pr33349.ll
llvm/test/CodeGen/X86/pr34177.ll
Removed:
################################################################################
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 520d8ed74a817e..7a9ee45c6beed4 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -53473,6 +53473,7 @@ static SDValue combineCMP(SDNode *N, SelectionDAG &DAG,
SDLoc dl(N);
SDValue Op = N->getOperand(0);
EVT VT = Op.getValueType();
+ const TargetLowering &TLI = DAG.getTargetLoweringInfo();
// If we have a constant logical shift that's only used in a comparison
// against zero turn it into an equivalent AND. This allows turning it into
@@ -53496,12 +53497,41 @@ static SDValue combineCMP(SDNode *N, SelectionDAG &DAG,
}
}
+ // If we're extracting from a avx512 bool vector and comparing against zero,
+ // then try to just bitcast the vector to an integer to use TEST/BT directly.
+ // (and (extract_elt (kshiftr vXi1, C), 0), 1) -> (and (bc vXi1), 1<<C)
+ if (Op.getOpcode() == ISD::AND && isOneConstant(Op.getOperand(1)) &&
+ Op.hasOneUse() && onlyZeroFlagUsed(SDValue(N, 0))) {
+ SDValue Src = Op.getOperand(0);
+ if (Src.getOpcode() == ISD::EXTRACT_VECTOR_ELT &&
+ isNullConstant(Src.getOperand(1)) &&
+ Src.getOperand(0).getValueType().getScalarType() == MVT::i1) {
+ SDValue BoolVec = Src.getOperand(0);
+ unsigned ShAmt = 0;
+ if (BoolVec.getOpcode() == X86ISD::KSHIFTR) {
+ ShAmt = BoolVec.getConstantOperandVal(1);
+ BoolVec = BoolVec.getOperand(0);
+ }
+ BoolVec = widenMaskVector(BoolVec, false, Subtarget, DAG, dl);
+ EVT VecVT = BoolVec.getValueType();
+ unsigned BitWidth = VecVT.getVectorNumElements();
+ EVT BCVT = EVT::getIntegerVT(*DAG.getContext(), BitWidth);
+ if (TLI.isTypeLegal(VecVT) && TLI.isTypeLegal(BCVT)) {
+ APInt Mask = APInt::getOneBitSet(BitWidth, ShAmt);
+ Op = DAG.getBitcast(BCVT, BoolVec);
+ Op = DAG.getNode(ISD::AND, dl, BCVT, Op,
+ DAG.getConstant(Mask, dl, BCVT));
+ return DAG.getNode(X86ISD::CMP, dl, MVT::i32, Op,
+ DAG.getConstant(0, dl, BCVT));
+ }
+ }
+ }
+
// Peek through any zero-extend if we're only testing for a zero result.
if (Op.getOpcode() == ISD::ZERO_EXTEND && onlyZeroFlagUsed(SDValue(N, 0))) {
SDValue Src = Op.getOperand(0);
EVT SrcVT = Src.getValueType();
- if (SrcVT.getScalarSizeInBits() >= 8 &&
- DAG.getTargetLoweringInfo().isTypeLegal(SrcVT))
+ if (SrcVT.getScalarSizeInBits() >= 8 && TLI.isTypeLegal(SrcVT))
return DAG.getNode(X86ISD::CMP, dl, MVT::i32, Src,
DAG.getConstant(0, dl, SrcVT));
}
diff --git a/llvm/test/CodeGen/X86/avx512-insert-extract.ll b/llvm/test/CodeGen/X86/avx512-insert-extract.ll
index 5728c14df14dd9..40cbbfe2c14e5d 100644
--- a/llvm/test/CodeGen/X86/avx512-insert-extract.ll
+++ b/llvm/test/CodeGen/X86/avx512-insert-extract.ll
@@ -175,9 +175,8 @@ define <16 x i32> @test11(<16 x i32>%a, <16 x i32>%b) nounwind {
; KNL-LABEL: test11:
; KNL: ## %bb.0:
; KNL-NEXT: vpcmpltud %zmm1, %zmm0, %k0
-; KNL-NEXT: kshiftrw $4, %k0, %k0
; KNL-NEXT: kmovw %k0, %eax
-; KNL-NEXT: testb $1, %al
+; KNL-NEXT: testb $16, %al
; KNL-NEXT: je LBB10_2
; KNL-NEXT: ## %bb.1: ## %A
; KNL-NEXT: vmovdqa64 %zmm1, %zmm0
@@ -189,9 +188,8 @@ define <16 x i32> @test11(<16 x i32>%a, <16 x i32>%b) nounwind {
; SKX-LABEL: test11:
; SKX: ## %bb.0:
; SKX-NEXT: vpcmpltud %zmm1, %zmm0, %k0
-; SKX-NEXT: kshiftrw $4, %k0, %k0
; SKX-NEXT: kmovd %k0, %eax
-; SKX-NEXT: testb $1, %al
+; SKX-NEXT: testb $16, %al
; SKX-NEXT: je LBB10_2
; SKX-NEXT: ## %bb.1: ## %A
; SKX-NEXT: vmovdqa64 %zmm1, %zmm0
@@ -276,9 +274,8 @@ define i64 @test14(<8 x i64>%a, <8 x i64>%b, i64 %a1, i64 %b1) nounwind {
; KNL: ## %bb.0:
; KNL-NEXT: movq %rdi, %rax
; KNL-NEXT: vpcmpgtq %zmm0, %zmm1, %k0
-; KNL-NEXT: kshiftrw $4, %k0, %k0
; KNL-NEXT: kmovw %k0, %ecx
-; KNL-NEXT: testb $1, %cl
+; KNL-NEXT: testb $16, %cl
; KNL-NEXT: cmoveq %rsi, %rax
; KNL-NEXT: vzeroupper
; KNL-NEXT: retq
@@ -287,9 +284,8 @@ define i64 @test14(<8 x i64>%a, <8 x i64>%b, i64 %a1, i64 %b1) nounwind {
; SKX: ## %bb.0:
; SKX-NEXT: movq %rdi, %rax
; SKX-NEXT: vpcmpgtq %zmm0, %zmm1, %k0
-; SKX-NEXT: kshiftrb $4, %k0, %k0
; SKX-NEXT: kmovd %k0, %ecx
-; SKX-NEXT: testb $1, %cl
+; SKX-NEXT: testb $16, %cl
; SKX-NEXT: cmoveq %rsi, %rax
; SKX-NEXT: vzeroupper
; SKX-NEXT: retq
diff --git a/llvm/test/CodeGen/X86/movmsk-cmp.ll b/llvm/test/CodeGen/X86/movmsk-cmp.ll
index 88d819d6106ea9..a0901e265f5ae9 100644
--- a/llvm/test/CodeGen/X86/movmsk-cmp.ll
+++ b/llvm/test/CodeGen/X86/movmsk-cmp.ll
@@ -4350,10 +4350,8 @@ define i32 @PR39665_c_ray(<2 x double> %x, <2 x double> %y) {
; KNL-NEXT: # kill: def $xmm1 killed $xmm1 def $zmm1
; KNL-NEXT: # kill: def $xmm0 killed $xmm0 def $zmm0
; KNL-NEXT: vcmpltpd %zmm0, %zmm1, %k0
-; KNL-NEXT: kshiftrw $1, %k0, %k1
-; KNL-NEXT: kmovw %k1, %eax
; KNL-NEXT: kmovw %k0, %ecx
-; KNL-NEXT: testb $1, %al
+; KNL-NEXT: testb $2, %cl
; KNL-NEXT: movl $42, %eax
; KNL-NEXT: movl $99, %edx
; KNL-NEXT: cmovel %edx, %eax
@@ -4365,10 +4363,8 @@ define i32 @PR39665_c_ray(<2 x double> %x, <2 x double> %y) {
; SKX-LABEL: PR39665_c_ray:
; SKX: # %bb.0:
; SKX-NEXT: vcmpltpd %xmm0, %xmm1, %k0
-; SKX-NEXT: kshiftrb $1, %k0, %k1
-; SKX-NEXT: kmovd %k1, %eax
; SKX-NEXT: kmovd %k0, %ecx
-; SKX-NEXT: testb $1, %al
+; SKX-NEXT: testb $2, %cl
; SKX-NEXT: movl $42, %eax
; SKX-NEXT: movl $99, %edx
; SKX-NEXT: cmovel %edx, %eax
diff --git a/llvm/test/CodeGen/X86/pr33349.ll b/llvm/test/CodeGen/X86/pr33349.ll
index 5addaca47c86ee..83d3a33572266f 100644
--- a/llvm/test/CodeGen/X86/pr33349.ll
+++ b/llvm/test/CodeGen/X86/pr33349.ll
@@ -11,32 +11,28 @@ target triple = "x86_64-unknown-linux-gnu"
; KNL-NEXT: vpslld $31, %xmm0, %xmm0
; KNL-NEXT: vptestmd %zmm0, %zmm0, %k0
; KNL-NEXT: kshiftrw $2, %k0, %k1
-; KNL-NEXT: kshiftrw $1, %k1, %k2
; KNL-NEXT: kmovw %k1, %eax
; KNL-NEXT: testb $1, %al
; KNL-NEXT: fld1
; KNL-NEXT: fldz
; KNL-NEXT: fld %st(0)
; KNL-NEXT: fcmovne %st(2), %st
-; KNL-NEXT: kmovw %k2, %eax
-; KNL-NEXT: testb $1, %al
+; KNL-NEXT: testb $2, %al
; KNL-NEXT: fld %st(1)
; KNL-NEXT: fcmovne %st(3), %st
-; KNL-NEXT: kshiftrw $1, %k0, %k1
-; KNL-NEXT: kmovw %k1, %eax
+; KNL-NEXT: kmovw %k0, %eax
; KNL-NEXT: testb $1, %al
; KNL-NEXT: fld %st(2)
; KNL-NEXT: fcmovne %st(4), %st
-; KNL-NEXT: kmovw %k0, %eax
-; KNL-NEXT: testb $1, %al
+; KNL-NEXT: testb $2, %al
; KNL-NEXT: fxch %st(3)
; KNL-NEXT: fcmovne %st(4), %st
; KNL-NEXT: fstp %st(4)
; KNL-NEXT: fxch %st(3)
-; KNL-NEXT: fstpt (%rdi)
-; KNL-NEXT: fxch %st(1)
; KNL-NEXT: fstpt 10(%rdi)
; KNL-NEXT: fxch %st(1)
+; KNL-NEXT: fstpt (%rdi)
+; KNL-NEXT: fxch %st(1)
; KNL-NEXT: fstpt 30(%rdi)
; KNL-NEXT: fstpt 20(%rdi)
; KNL-NEXT: vzeroupper
@@ -47,32 +43,28 @@ target triple = "x86_64-unknown-linux-gnu"
; SKX-NEXT: vpslld $31, %xmm0, %xmm0
; SKX-NEXT: vpmovd2m %xmm0, %k0
; SKX-NEXT: kshiftrb $2, %k0, %k1
-; SKX-NEXT: kshiftrb $1, %k1, %k2
; SKX-NEXT: kmovd %k1, %eax
; SKX-NEXT: testb $1, %al
; SKX-NEXT: fld1
; SKX-NEXT: fldz
; SKX-NEXT: fld %st(0)
; SKX-NEXT: fcmovne %st(2), %st
-; SKX-NEXT: kmovd %k2, %eax
-; SKX-NEXT: testb $1, %al
+; SKX-NEXT: testb $2, %al
; SKX-NEXT: fld %st(1)
; SKX-NEXT: fcmovne %st(3), %st
-; SKX-NEXT: kshiftrb $1, %k0, %k1
-; SKX-NEXT: kmovd %k1, %eax
+; SKX-NEXT: kmovd %k0, %eax
; SKX-NEXT: testb $1, %al
; SKX-NEXT: fld %st(2)
; SKX-NEXT: fcmovne %st(4), %st
-; SKX-NEXT: kmovd %k0, %eax
-; SKX-NEXT: testb $1, %al
+; SKX-NEXT: testb $2, %al
; SKX-NEXT: fxch %st(3)
; SKX-NEXT: fcmovne %st(4), %st
; SKX-NEXT: fstp %st(4)
; SKX-NEXT: fxch %st(3)
-; SKX-NEXT: fstpt (%rdi)
-; SKX-NEXT: fxch %st(1)
; SKX-NEXT: fstpt 10(%rdi)
; SKX-NEXT: fxch %st(1)
+; SKX-NEXT: fstpt (%rdi)
+; SKX-NEXT: fxch %st(1)
; SKX-NEXT: fstpt 30(%rdi)
; SKX-NEXT: fstpt 20(%rdi)
; SKX-NEXT: retq
diff --git a/llvm/test/CodeGen/X86/pr34177.ll b/llvm/test/CodeGen/X86/pr34177.ll
index 2653fcdcb75cad..29922c2ac1a716 100644
--- a/llvm/test/CodeGen/X86/pr34177.ll
+++ b/llvm/test/CodeGen/X86/pr34177.ll
@@ -49,24 +49,20 @@ define void @test(<4 x i64> %a, <4 x x86_fp80> %b, ptr %c) local_unnamed_addr {
; AVX512VL-LABEL: test:
; AVX512VL: # %bb.0:
; AVX512VL-NEXT: vpcmpeqq {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %ymm0, %k0
-; AVX512VL-NEXT: kshiftrb $1, %k0, %k1
-; AVX512VL-NEXT: kshiftrb $2, %k0, %k2
+; AVX512VL-NEXT: kshiftrb $2, %k0, %k1
; AVX512VL-NEXT: kmovd %k0, %eax
-; AVX512VL-NEXT: testb $1, %al
+; AVX512VL-NEXT: testb $2, %al
; AVX512VL-NEXT: fld1
; AVX512VL-NEXT: fldz
; AVX512VL-NEXT: fld %st(0)
; AVX512VL-NEXT: fcmovne %st(2), %st
-; AVX512VL-NEXT: kmovd %k1, %eax
; AVX512VL-NEXT: testb $1, %al
; AVX512VL-NEXT: fld %st(1)
; AVX512VL-NEXT: fcmovne %st(3), %st
-; AVX512VL-NEXT: kshiftrb $1, %k2, %k0
-; AVX512VL-NEXT: kmovd %k0, %eax
-; AVX512VL-NEXT: testb $1, %al
+; AVX512VL-NEXT: kmovd %k1, %eax
+; AVX512VL-NEXT: testb $2, %al
; AVX512VL-NEXT: fld %st(2)
; AVX512VL-NEXT: fcmovne %st(4), %st
-; AVX512VL-NEXT: kmovd %k2, %eax
; AVX512VL-NEXT: testb $1, %al
; AVX512VL-NEXT: fxch %st(3)
; AVX512VL-NEXT: fcmovne %st(4), %st
@@ -81,10 +77,10 @@ define void @test(<4 x i64> %a, <4 x x86_fp80> %b, ptr %c) local_unnamed_addr {
; AVX512VL-NEXT: fstpt 10(%rdi)
; AVX512VL-NEXT: fxch %st(1)
; AVX512VL-NEXT: fadd %st, %st(0)
-; AVX512VL-NEXT: fstpt (%rdi)
-; AVX512VL-NEXT: fadd %st, %st(0)
; AVX512VL-NEXT: fstpt 20(%rdi)
; AVX512VL-NEXT: fadd %st, %st(0)
+; AVX512VL-NEXT: fstpt (%rdi)
+; AVX512VL-NEXT: fadd %st, %st(0)
; AVX512VL-NEXT: fstpt 60(%rdi)
; AVX512VL-NEXT: fadd %st, %st(0)
; AVX512VL-NEXT: fstpt 40(%rdi)
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