[llvm] 9ace23c - [InstCombine] Avoid use of ConstantExpr::getSExt() (NFC)

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2023-10-02T11:30:15+02:00
New Revision: 9ace23c9a20f82758288b5b99a8a82b36e97bdc5

URL: https://github.com/llvm/llvm-project/commit/9ace23c9a20f82758288b5b99a8a82b36e97bdc5
DIFF: https://github.com/llvm/llvm-project/commit/9ace23c9a20f82758288b5b99a8a82b36e97bdc5.diff

LOG: [InstCombine] Avoid use of ConstantExpr::getSExt() (NFC)

Use the constant folding API instead.

Added: 
    

Modified: 
    llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
    llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
index 951492cc150f304..20c13de33f8189d 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -1445,9 +1445,11 @@ Instruction *InstCombinerImpl::visitSExt(SExtInst &Sext) {
   // TODO: Eventually this could be subsumed by EvaluateInDifferentType.
   Constant *BA = nullptr, *CA = nullptr;
   if (match(Src, m_AShr(m_Shl(m_Trunc(m_Value(A)), m_Constant(BA)),
-                        m_Constant(CA))) &&
+                        m_ImmConstant(CA))) &&
       BA->isElementWiseEqual(CA) && A->getType() == DestTy) {
-    Constant *WideCurrShAmt = ConstantExpr::getSExt(CA, DestTy);
+    Constant *WideCurrShAmt =
+        ConstantFoldCastOperand(Instruction::SExt, CA, DestTy, DL);
+    assert(WideCurrShAmt && "Constant folding of ImmConstant cannot fail");
     Constant *NumLowbitsLeft = ConstantExpr::getSub(
         ConstantInt::get(DestTy, SrcTy->getScalarSizeInBits()), WideCurrShAmt);
     Constant *NewShAmt = ConstantExpr::getSub(

diff  --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index c42164da8aee1ab..7a15c0dee492b5a 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -1495,8 +1495,13 @@ static Value *canonicalizeClampLike(SelectInst &Sel0, ICmpInst &Cmp0,
     if (!match(ReplacementLow, m_ImmConstant(LowC)) ||
         !match(ReplacementHigh, m_ImmConstant(HighC)))
       return nullptr;
-    ReplacementLow = ConstantExpr::getSExt(LowC, X->getType());
-    ReplacementHigh = ConstantExpr::getSExt(HighC, X->getType());
+    const DataLayout &DL = Sel0.getModule()->getDataLayout();
+    ReplacementLow =
+        ConstantFoldCastOperand(Instruction::SExt, LowC, X->getType(), DL);
+    ReplacementHigh =
+        ConstantFoldCastOperand(Instruction::SExt, HighC, X->getType(), DL);
+    assert(ReplacementLow && ReplacementHigh &&
+           "Constant folding of ImmConstant cannot fail");
   }
 
   // All good, finally emit the new pattern.