diff options
Diffstat (limited to 'llvm/lib/Analysis/BranchProbabilityInfo.cpp')
| -rw-r--r-- | llvm/lib/Analysis/BranchProbabilityInfo.cpp | 27 |
1 files changed, 10 insertions, 17 deletions
diff --git a/llvm/lib/Analysis/BranchProbabilityInfo.cpp b/llvm/lib/Analysis/BranchProbabilityInfo.cpp index 6df90e6..eae2c4e 100644 --- a/llvm/lib/Analysis/BranchProbabilityInfo.cpp +++ b/llvm/lib/Analysis/BranchProbabilityInfo.cpp @@ -122,8 +122,8 @@ static const uint32_t CC_NONTAKEN_WEIGHT = 64; static const uint32_t PH_TAKEN_WEIGHT = 20; static const uint32_t PH_NONTAKEN_WEIGHT = 12; -static const uint32_t INTH_TAKEN_WEIGHT = 20; -static const uint32_t INTH_NONTAKEN_WEIGHT = 12; +static const uint32_t ZH_TAKEN_WEIGHT = 20; +static const uint32_t ZH_NONTAKEN_WEIGHT = 12; static const uint32_t FPH_TAKEN_WEIGHT = 20; static const uint32_t FPH_NONTAKEN_WEIGHT = 12; @@ -856,7 +856,7 @@ bool BranchProbabilityInfo::calcLoopBranchHeuristics(const BasicBlock *BB, return true; } -bool BranchProbabilityInfo::calcIntegerHeuristics(const BasicBlock *BB, +bool BranchProbabilityInfo::calcZeroHeuristics(const BasicBlock *BB, const TargetLibraryInfo *TLI) { const BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator()); if (!BI || !BI->isConditional()) @@ -873,21 +873,10 @@ bool BranchProbabilityInfo::calcIntegerHeuristics(const BasicBlock *BB, return dyn_cast<ConstantInt>(V); }; - BranchProbability TakenProb(INTH_TAKEN_WEIGHT, - INTH_TAKEN_WEIGHT + INTH_NONTAKEN_WEIGHT); - BranchProbability UntakenProb(INTH_NONTAKEN_WEIGHT, - INTH_TAKEN_WEIGHT + INTH_NONTAKEN_WEIGHT); Value *RHS = CI->getOperand(1); ConstantInt *CV = GetConstantInt(RHS); - if (!CV) { - // X == Y -> Unlikely - // Otherwise -> Likely - if (CI->isTrueWhenEqual()) - std::swap(TakenProb, UntakenProb); - setEdgeProbability( - BB, SmallVector<BranchProbability, 2>({TakenProb, UntakenProb})); - return true; - } + if (!CV) + return false; // If the LHS is the result of AND'ing a value with a single bit bitmask, // we don't have information about probabilities. @@ -975,6 +964,10 @@ bool BranchProbabilityInfo::calcIntegerHeuristics(const BasicBlock *BB, return false; } + BranchProbability TakenProb(ZH_TAKEN_WEIGHT, + ZH_TAKEN_WEIGHT + ZH_NONTAKEN_WEIGHT); + BranchProbability UntakenProb(ZH_NONTAKEN_WEIGHT, + ZH_TAKEN_WEIGHT + ZH_NONTAKEN_WEIGHT); if (!isProb) std::swap(TakenProb, UntakenProb); @@ -1228,7 +1221,7 @@ void BranchProbabilityInfo::calculate(const Function &F, const LoopInfo &LI, continue; if (calcPointerHeuristics(BB)) continue; - if (calcIntegerHeuristics(BB, TLI)) + if (calcZeroHeuristics(BB, TLI)) continue; if (calcFloatingPointHeuristics(BB)) continue; |