[llvm] 5b08bd0 - Fix MemCpyOptimizer return status

[via llvm-commits]

Author: serge-sans-paille
Date: 2020-06-09T14:24:33+02:00
New Revision: 5b08bd0eb48803057fcd18e7eb9357e3cb3cdb83

URL: https://github.com/llvm/llvm-project/commit/5b08bd0eb48803057fcd18e7eb9357e3cb3cdb83
DIFF: https://github.com/llvm/llvm-project/commit/5b08bd0eb48803057fcd18e7eb9357e3cb3cdb83.diff

LOG: Fix MemCpyOptimizer return status

Differential Revision: https://reviews.llvm.org/D81229

Added: 
    

Modified: 
    llvm/include/llvm/Transforms/Scalar/MemCpyOptimizer.h
    llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp

Removed: 
    


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diff  --git a/llvm/include/llvm/Transforms/Scalar/MemCpyOptimizer.h b/llvm/include/llvm/Transforms/Scalar/MemCpyOptimizer.h
index c1910358fc80..1570c3a08d0b 100644
--- a/llvm/include/llvm/Transforms/Scalar/MemCpyOptimizer.h
+++ b/llvm/include/llvm/Transforms/Scalar/MemCpyOptimizer.h
@@ -58,7 +58,7 @@ class MemCpyOptPass : public PassInfoMixin<MemCpyOptPass> {
   // Helper functions
   bool processStore(StoreInst *SI, BasicBlock::iterator &BBI);
   bool processMemSet(MemSetInst *SI, BasicBlock::iterator &BBI);
-  bool processMemCpy(MemCpyInst *M);
+  bool processMemCpy(MemCpyInst *M, BasicBlock::iterator &BBI);
   bool processMemMove(MemMoveInst *M);
   bool performCallSlotOptzn(Instruction *cpy, Value *cpyDst, Value *cpySrc,
                             uint64_t cpyLen, Align cpyAlign, CallInst *C);

diff  --git a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index 73144953ccd4..4b4196edc12b 100644
--- a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -1097,15 +1097,16 @@ bool MemCpyOptPass::performMemCpyToMemSetOptzn(MemCpyInst *MemCpy,
 /// B to be a memcpy from X to Z (or potentially a memmove, depending on
 /// circumstances). This allows later passes to remove the first memcpy
 /// altogether.
-bool MemCpyOptPass::processMemCpy(MemCpyInst *M) {
+bool MemCpyOptPass::processMemCpy(MemCpyInst *M, BasicBlock::iterator &BBI) {
   // We can only optimize non-volatile memcpy's.
   if (M->isVolatile()) return false;
 
   // If the source and destination of the memcpy are the same, then zap it.
   if (M->getSource() == M->getDest()) {
+    ++BBI;
     MD->removeInstruction(M);
     M->eraseFromParent();
-    return false;
+    return true;
   }
 
   // If copying from a constant, try to turn the memcpy into a memset.
@@ -1322,7 +1323,7 @@ bool MemCpyOptPass::iterateOnFunction(Function &F) {
       else if (MemSetInst *M = dyn_cast<MemSetInst>(I))
         RepeatInstruction = processMemSet(M, BI);
       else if (MemCpyInst *M = dyn_cast<MemCpyInst>(I))
-        RepeatInstruction = processMemCpy(M);
+        RepeatInstruction = processMemCpy(M, BI);
       else if (MemMoveInst *M = dyn_cast<MemMoveInst>(I))
         RepeatInstruction = processMemMove(M);
       else if (auto *CB = dyn_cast<CallBase>(I)) {