[llvm] a9ddcd6 - [InstCombine] Erase old add when optimizing add overflow

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2020-03-29T20:20:14+02:00
New Revision: a9ddcd6411bcbffe551641a91413c417de491189

URL: https://github.com/llvm/llvm-project/commit/a9ddcd6411bcbffe551641a91413c417de491189
DIFF: https://github.com/llvm/llvm-project/commit/a9ddcd6411bcbffe551641a91413c417de491189.diff

LOG: [InstCombine] Erase old add when optimizing add overflow

We don't return the replaceInstUsesWith() result, so we're
responsible for cleaning up.

NFC apart from worklist order changes.

Added: 
    

Modified: 
    llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index f36dcacdad28..259481041302 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -5618,6 +5618,7 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
           OptimizeOverflowCheck(Instruction::Add, /*Signed*/ false, A, B, *AddI,
                                 Result, Overflow)) {
         replaceInstUsesWith(*AddI, Result);
+        eraseInstFromFunction(*AddI);
         return replaceInstUsesWith(I, Overflow);
       }
     }