[llvm] 210ecf7 - [Instrumentor] Use CreateAllocationSize to compute size of alloca (#226330)

[via llvm-commits]

Author: Eli Friedman
Date: 2026-09-25T14:10:38-07:00
New Revision: 210ecf77c9021941ee32c496df8b715615163df4

URL: https://github.com/llvm/llvm-project/commit/210ecf77c9021941ee32c496df8b715615163df4
DIFF: https://github.com/llvm/llvm-project/commit/210ecf77c9021941ee32c496df8b715615163df4.diff

LOG: [Instrumentor] Use CreateAllocationSize to compute size of alloca (#226330)

No significant functional change, but the IR might look slightly
different.

Added: 
    

Modified: 
    llvm/lib/Transforms/IPO/Instrumentor.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/IPO/Instrumentor.cpp b/llvm/lib/Transforms/IPO/Instrumentor.cpp
index c12ff5e69c03d..afbfcdb196afb 100644
--- a/llvm/lib/Transforms/IPO/Instrumentor.cpp
+++ b/llvm/lib/Transforms/IPO/Instrumentor.cpp
@@ -1171,22 +1171,7 @@ void AllocaIO::init(InstrumentationConfig &IConf, InstrumentorIRBuilderTy &IIRB,
 Value *AllocaIO::getSize(Value &V, Type &Ty, InstrumentationConfig &IO,
                          InstrumentorIRBuilderTy &IIRB) {
   auto &AI = cast<AllocaInst>(V);
-  const DataLayout &DL = AI.getDataLayout();
-  Value *SizeValue = nullptr;
-  TypeSize TypeSize = AI.getAllocationBaseSize(DL);
-  if (TypeSize.isFixed()) {
-    SizeValue = getCI(&Ty, TypeSize.getFixedValue());
-  } else {
-    auto *NullPtr = ConstantPointerNull::get(AI.getType());
-    SizeValue = IIRB.IRB.CreatePtrToInt(
-        IIRB.IRB.CreateGEP(AI.getAllocatedType(), NullPtr,
-                           {IIRB.IRB.getInt32(1)}),
-        &Ty);
-  }
-  if (AI.isArrayAllocation())
-    SizeValue = IIRB.IRB.CreateMul(
-        SizeValue, IIRB.IRB.CreateZExtOrBitCast(AI.getArraySize(), &Ty));
-  return SizeValue;
+  return IIRB.IRB.CreateAllocationSize(&Ty, &AI);
 }
 
 Value *AllocaIO::setSize(Value &V, Value &NewV, InstrumentationConfig &IO,