[llvm] r353051 - [X86][SSE] SimplifyDemandedBitsForTargetNode - PCMPGT(0, X) sign mask

Simon Pilgrim via llvm-commits llvm-commits at lists.llvm.org
Mon Feb 4 07:43:36 PST 2019


Author: rksimon
Date: Mon Feb  4 07:43:36 2019
New Revision: 353051

URL: http://llvm.org/viewvc/llvm-project?rev=353051&view=rev
Log:
[X86][SSE] SimplifyDemandedBitsForTargetNode - PCMPGT(0,X) sign mask

For PCMPGT(0, X) patterns where we only demand the sign bit (e.g. BLENDV or MOVMSK) then we can use X directly.

Differential Revision: https://reviews.llvm.org/D57667

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/avx512-cvt-widen.ll
    llvm/trunk/test/CodeGen/X86/avx512-cvt.ll
    llvm/trunk/test/CodeGen/X86/bitcast-setcc-128.ll
    llvm/trunk/test/CodeGen/X86/bitcast-setcc-256.ll
    llvm/trunk/test/CodeGen/X86/bitcast-setcc-512.ll
    llvm/trunk/test/CodeGen/X86/movmsk-cmp.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Mon Feb  4 07:43:36 2019
@@ -33070,6 +33070,13 @@ bool X86TargetLowering::SimplifyDemanded
     }
     break;
   }
+  case X86ISD::PCMPGT:
+    // icmp sgt(0, R) == ashr(R, BitWidth-1).
+    // iff we only need the sign bit then we can use R directly.
+    if (OriginalDemandedBits.isSignMask() &&
+        ISD::isBuildVectorAllZeros(Op.getOperand(0).getNode()))
+      return TLO.CombineTo(Op, Op.getOperand(1));
+    break;
   case X86ISD::MOVMSK: {
     SDValue Src = Op.getOperand(0);
     MVT SrcVT = Src.getSimpleValueType();

Modified: llvm/trunk/test/CodeGen/X86/avx512-cvt-widen.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx512-cvt-widen.ll?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx512-cvt-widen.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx512-cvt-widen.ll Mon Feb  4 07:43:36 2019
@@ -1909,8 +1909,6 @@ define <8 x float> @ubto8f32(<8 x i32> %
 define <8 x double> @ubto8f64(<8 x i32> %a) {
 ; ALL-LABEL: ubto8f64:
 ; ALL:       # %bb.0:
-; ALL-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; ALL-NEXT:    vpcmpgtd %ymm0, %ymm1, %ymm0
 ; ALL-NEXT:    vpsrld $31, %ymm0, %ymm0
 ; ALL-NEXT:    vcvtdq2pd %ymm0, %zmm0
 ; ALL-NEXT:    retq
@@ -1942,8 +1940,6 @@ define <4 x float> @ubto4f32(<4 x i32> %
 define <4 x double> @ubto4f64(<4 x i32> %a) {
 ; ALL-LABEL: ubto4f64:
 ; ALL:       # %bb.0:
-; ALL-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; ALL-NEXT:    vpcmpgtd %xmm0, %xmm1, %xmm0
 ; ALL-NEXT:    vpsrld $31, %xmm0, %xmm0
 ; ALL-NEXT:    vcvtdq2pd %xmm0, %ymm0
 ; ALL-NEXT:    retq

Modified: llvm/trunk/test/CodeGen/X86/avx512-cvt.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx512-cvt.ll?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx512-cvt.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx512-cvt.ll Mon Feb  4 07:43:36 2019
@@ -1897,8 +1897,6 @@ define <8 x float> @ubto8f32(<8 x i32> %
 define <8 x double> @ubto8f64(<8 x i32> %a) {
 ; ALL-LABEL: ubto8f64:
 ; ALL:       # %bb.0:
-; ALL-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; ALL-NEXT:    vpcmpgtd %ymm0, %ymm1, %ymm0
 ; ALL-NEXT:    vpsrld $31, %ymm0, %ymm0
 ; ALL-NEXT:    vcvtdq2pd %ymm0, %zmm0
 ; ALL-NEXT:    retq
@@ -1930,8 +1928,6 @@ define <4 x float> @ubto4f32(<4 x i32> %
 define <4 x double> @ubto4f64(<4 x i32> %a) {
 ; ALL-LABEL: ubto4f64:
 ; ALL:       # %bb.0:
-; ALL-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; ALL-NEXT:    vpcmpgtd %xmm0, %xmm1, %xmm0
 ; ALL-NEXT:    vpsrld $31, %xmm0, %xmm0
 ; ALL-NEXT:    vcvtdq2pd %xmm0, %ymm0
 ; ALL-NEXT:    retq

Modified: llvm/trunk/test/CodeGen/X86/bitcast-setcc-128.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/bitcast-setcc-128.ll?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/bitcast-setcc-128.ll (original)
+++ llvm/trunk/test/CodeGen/X86/bitcast-setcc-128.ll Mon Feb  4 07:43:36 2019
@@ -683,9 +683,6 @@ define i64 @v16i8_widened_with_ones(<16
 ; AVX1:       # %bb.0: # %entry
 ; AVX1-NEXT:    vpcmpeqb %xmm1, %xmm0, %xmm0
 ; AVX1-NEXT:    vpsllw $7, %xmm0, %xmm0
-; AVX1-NEXT:    vpand {{.*}}(%rip), %xmm0, %xmm0
-; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    orl $-65536, %ecx # imm = 0xFFFF0000
 ; AVX1-NEXT:    movabsq $-4294967296, %rax # imm = 0xFFFFFFFF00000000

Modified: llvm/trunk/test/CodeGen/X86/bitcast-setcc-256.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/bitcast-setcc-256.ll?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/bitcast-setcc-256.ll (original)
+++ llvm/trunk/test/CodeGen/X86/bitcast-setcc-256.ll Mon Feb  4 07:43:36 2019
@@ -314,11 +314,8 @@ define void @bitcast_32i8_store(i32* %p,
 ;
 ; AVX1-LABEL: bitcast_32i8_store:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm2
-; AVX1-NEXT:    vpmovmskb %xmm2, %eax
+; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    shll $16, %ecx
 ; AVX1-NEXT:    orl %eax, %ecx

Modified: llvm/trunk/test/CodeGen/X86/bitcast-setcc-512.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/bitcast-setcc-512.ll?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/bitcast-setcc-512.ll (original)
+++ llvm/trunk/test/CodeGen/X86/bitcast-setcc-512.ll Mon Feb  4 07:43:36 2019
@@ -418,18 +418,13 @@ define void @bitcast_64i8_store(i64* %p,
 ;
 ; AVX1-LABEL: bitcast_64i8_store:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm3
-; AVX1-NEXT:    vpmovmskb %xmm3, %eax
+; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    shll $16, %ecx
 ; AVX1-NEXT:    orl %eax, %ecx
-; AVX1-NEXT:    vpcmpgtb %xmm1, %xmm2, %xmm0
-; AVX1-NEXT:    vpmovmskb %xmm0, %eax
+; AVX1-NEXT:    vpmovmskb %xmm1, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm1, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %edx
 ; AVX1-NEXT:    shll $16, %edx
 ; AVX1-NEXT:    orl %eax, %edx

Modified: llvm/trunk/test/CodeGen/X86/movmsk-cmp.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/movmsk-cmp.ll?rev=353051&r1=353050&r2=353051&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/movmsk-cmp.ll (original)
+++ llvm/trunk/test/CodeGen/X86/movmsk-cmp.ll Mon Feb  4 07:43:36 2019
@@ -86,11 +86,8 @@ define i1 @allones_v32i8_sign(<32 x i8>
 ;
 ; AVX1-LABEL: allones_v32i8_sign:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm2
-; AVX1-NEXT:    vpmovmskb %xmm2, %eax
+; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    shll $16, %ecx
 ; AVX1-NEXT:    orl %eax, %ecx
@@ -140,11 +137,8 @@ define i1 @allzeros_v32i8_sign(<32 x i8>
 ;
 ; AVX1-LABEL: allzeros_v32i8_sign:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm2
-; AVX1-NEXT:    vpmovmskb %xmm2, %eax
+; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    shll $16, %ecx
 ; AVX1-NEXT:    orl %eax, %ecx
@@ -200,18 +194,13 @@ define i1 @allones_v64i8_sign(<64 x i8>
 ;
 ; AVX1-LABEL: allones_v64i8_sign:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm3
-; AVX1-NEXT:    vpmovmskb %xmm3, %eax
+; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    shll $16, %ecx
 ; AVX1-NEXT:    orl %eax, %ecx
-; AVX1-NEXT:    vpcmpgtb %xmm1, %xmm2, %xmm0
-; AVX1-NEXT:    vpmovmskb %xmm0, %eax
+; AVX1-NEXT:    vpmovmskb %xmm1, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm1, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %edx
 ; AVX1-NEXT:    shll $16, %edx
 ; AVX1-NEXT:    orl %eax, %edx
@@ -275,18 +264,13 @@ define i1 @allzeros_v64i8_sign(<64 x i8>
 ;
 ; AVX1-LABEL: allzeros_v64i8_sign:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm3
-; AVX1-NEXT:    vpmovmskb %xmm3, %eax
+; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    shll $16, %ecx
 ; AVX1-NEXT:    orl %eax, %ecx
-; AVX1-NEXT:    vpcmpgtb %xmm1, %xmm2, %xmm0
-; AVX1-NEXT:    vpmovmskb %xmm0, %eax
+; AVX1-NEXT:    vpmovmskb %xmm1, %eax
 ; AVX1-NEXT:    vextractf128 $1, %ymm1, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm2, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %edx
 ; AVX1-NEXT:    shll $16, %edx
 ; AVX1-NEXT:    orl %eax, %edx
@@ -4756,11 +4740,8 @@ define i32 @movmskb256(<32 x i8> %x) {
 ;
 ; AVX1-LABEL: movmskb256:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm2
-; AVX1-NEXT:    vpmovmskb %xmm2, %ecx
+; AVX1-NEXT:    vpmovmskb %xmm0, %ecx
 ; AVX1-NEXT:    vextractf128 $1, %ymm0, %xmm0
-; AVX1-NEXT:    vpcmpgtb %xmm0, %xmm1, %xmm0
 ; AVX1-NEXT:    vpmovmskb %xmm0, %eax
 ; AVX1-NEXT:    shll $16, %eax
 ; AVX1-NEXT:    orl %ecx, %eax




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