diff options
| -rw-r--r-- | lib/Transforms/Scalar/InstructionCombining.cpp | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 0f676426e1..0812fca6e9 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -26,6 +26,7 @@ #include "llvm/Support/InstIterator.h" #include "llvm/Support/InstVisitor.h" #include "Support/StatisticReporter.h" +#include <algorithm> static Statistic<> NumCombined("instcombine\t- Number of insts combined"); @@ -551,8 +552,18 @@ bool InstCombiner::runOnFunction(Function *F) { if (Result) { ++NumCombined; // Should we replace the old instruction with a new one? - if (Result != I) + if (Result != I) { + // Instructions can end up on the worklist more than once. Make sure + // we do not process an instruction that has been deleted. + std::vector<Instruction*>::iterator It = std::find(WorkList.begin(), + WorkList.end(), I); + while (It != WorkList.end()) { + It = WorkList.erase(It); + It = std::find(It, WorkList.end(), I); + } + ReplaceInstWithInst(I, Result); + } WorkList.push_back(Result); AddUsesToWorkList(Result); |