diff options
Diffstat (limited to 'lib/Transforms/Utils/SimplifyCFG.cpp')
| -rw-r--r-- | lib/Transforms/Utils/SimplifyCFG.cpp | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp index d56bb32931..ff50b12cdb 100644 --- a/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/lib/Transforms/Utils/SimplifyCFG.cpp @@ -2090,8 +2090,13 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI) { // Ensure that any values used in the bonus instruction are also used // by the terminator of the predecessor. This means that those values // must already have been resolved, so we won't be inhibiting the - // out-of-order core by speculating them earlier. - if (BonusInst) { + // out-of-order core by speculating them earlier. We also allow + // instructions that are used by the terminator's condition because it + // exposes more merging opportunities. + bool UsedByBranch = (BonusInst && BonusInst->hasOneUse() && + *BonusInst->use_begin() == Cond); + + if (BonusInst && !UsedByBranch) { // Collect the values used by the bonus inst SmallPtrSet<Value*, 4> UsedValues; for (Instruction::op_iterator OI = BonusInst->op_begin(), |