[llvm] cfe3160 - [SelectionDAGBuilder] Use getConstant instead of getTargetConstant to build the offset for struct types in getUniformBase.

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2019-12-18T10:44:28-08:00
New Revision: cfe316007fb8492535d697717c24ce72621a8d5e

URL: https://github.com/llvm/llvm-project/commit/cfe316007fb8492535d697717c24ce72621a8d5e
DIFF: https://github.com/llvm/llvm-project/commit/cfe316007fb8492535d697717c24ce72621a8d5e.diff

LOG: [SelectionDAGBuilder] Use getConstant instead of getTargetConstant to build the offset for struct types in getUniformBase.

getTargetConstant prevents any optimizations from operating on the
value and basically says its already been iseled. But since we
want the index to be in a register, this isn't true.

Prior to this we were generating a vbroadcast with an immediate
argument which is illegal and was flagged by the expensive checks
bot.

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
    llvm/test/CodeGen/X86/masked_gather.ll

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 735ac67ebfc9..c69fe55a4f15 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4390,8 +4390,8 @@ static bool getUniformBase(const Value *&Ptr, SDValue &Base, SDValue &Index,
     }
     auto *CI = cast<ConstantInt>(C);
     Scale = DAG.getTargetConstant(1, SDB->getCurSDLoc(), TLI.getPointerTy(DL));
-    Index = DAG.getTargetConstant(SL->getElementOffset(CI->getZExtValue()),
-                                  SDB->getCurSDLoc(), TLI.getPointerTy(DL));
+    Index = DAG.getConstant(SL->getElementOffset(CI->getZExtValue()),
+                            SDB->getCurSDLoc(), TLI.getPointerTy(DL));
   } else {
     Scale = DAG.getTargetConstant(
                 DL.getTypeAllocSize(GEP->getResultElementType()),

diff  --git a/llvm/test/CodeGen/X86/masked_gather.ll b/llvm/test/CodeGen/X86/masked_gather.ll
index dd41009a9aee..7ea2cacd77b1 100644
--- a/llvm/test/CodeGen/X86/masked_gather.ll
+++ b/llvm/test/CodeGen/X86/masked_gather.ll
@@ -1725,13 +1725,14 @@ define <8 x i32> @gather_v8i32_v8i32(<8 x i32> %trigger) {
 ; AVX512-LABEL: gather_v8i32_v8i32:
 ; AVX512:       # %bb.0:
 ; AVX512-NEXT:    # kill: def $ymm0 killed $ymm0 def $zmm0
-; AVX512-NEXT:    vptestnmd %zmm0, %zmm0, %k1
-; AVX512-NEXT:    kshiftlw $8, %k1, %k0
-; AVX512-NEXT:    kshiftrw $8, %k0, %k2
+; AVX512-NEXT:    vptestnmd %zmm0, %zmm0, %k0
+; AVX512-NEXT:    kshiftlw $8, %k0, %k0
+; AVX512-NEXT:    kshiftrw $8, %k0, %k1
 ; AVX512-NEXT:    vpbroadcastd {{.*#+}} zmm0 = [3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3]
+; AVX512-NEXT:    kmovw %k1, %k2
 ; AVX512-NEXT:    vpgatherdd c(,%zmm0,4), %zmm1 {%k2}
-; AVX512-NEXT:    vpbroadcastq $28, %zmm0
-; AVX512-NEXT:    vpgatherqd c(,%zmm0), %ymm2 {%k1}
+; AVX512-NEXT:    vpbroadcastd {{.*#+}} zmm0 = [28,28,28,28,28,28,28,28,28,28,28,28,28,28,28,28]
+; AVX512-NEXT:    vpgatherdd c(,%zmm0), %zmm2 {%k1}
 ; AVX512-NEXT:    vpaddd %ymm2, %ymm2, %ymm0
 ; AVX512-NEXT:    vpaddd %ymm0, %ymm1, %ymm0
 ; AVX512-NEXT:    retq