diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp index 2327ba4995c..80b138e8c36 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp @@ -1820,6 +1820,13 @@ Instruction *InstCombiner::optimizeBitCastFromPhi(CastInst &CI, PHINode *PN) { auto *LI = dyn_cast<LoadInst>(IncValue); if (LI) { + // If there is a sequence of one or more load instructions, each loaded + // value is used as address of later load instruction, bitcast is + // necessary to change the value type, don't optimize it. For + // simplicity we give up if the load address comes from another load. + Value *Addr = LI->getOperand(0); + if (Addr == &CI || isa<LoadInst>(Addr)) + return nullptr; if (LI->hasOneUse() && LI->isSimple()) continue; // If a LoadInst has more than one use, changing the type of loaded |
