[InstCombine] return the result of the GEP of PHI transformation early

Without this change this function could return nullptr if no further
transformation took place making InstCombine pass incorrectly report no
IR changes preventing analyses invalidation.

Differential Revision: https://reviews.llvm.org/D140004

diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 38a79f0..1d34463 100644 (file)
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -2420,8 +2420,7 @@ Instruction *InstCombinerImpl::visitGetElementPtrInst(GetElementPtrInst &GEP) {
     }
 
     NewGEP->insertAt(GEP.getParent(), GEP.getParent()->getFirstInsertionPt());
-    replaceOperand(GEP, 0, NewGEP);
-    PtrOp = NewGEP;
+    return replaceOperand(GEP, 0, NewGEP);
   }
 
   if (auto *Src = dyn_cast<GEPOperator>(PtrOp))