Revert "Move function to obtain branch weights into the BranchInst class. NFC."
This reverts commit r223784 and copies the 'ExtractBranchMetadata' to CodeGenPrepare.
llvm-svn: 223795
diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index 8b92cf2..e043bfb 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -3800,6 +3800,27 @@
return MadeChange;
}
+/// \brief Retrieve the probabilities of a conditional branch. Returns true on
+/// success, or returns false if no or invalid metadata was found.
+static bool extractBranchMetadata(BranchInst *BI,
+ uint64_t &ProbTrue, uint64_t &ProbFalse) {
+ assert(BI->isConditional() &&
+ "Looking for probabilities on unconditional branch?");
+ auto *ProfileData = BI->getMetadata(LLVMContext::MD_prof);
+ if (!ProfileData || ProfileData->getNumOperands() != 3)
+ return false;
+
+ const auto *CITrue = dyn_cast<ConstantInt>(ProfileData->getOperand(1));
+ const auto *CIFalse = dyn_cast<ConstantInt>(ProfileData->getOperand(2));
+ if (!CITrue || !CIFalse)
+ return false;
+
+ ProbTrue = CITrue->getValue().getZExtValue();
+ ProbFalse = CIFalse->getValue().getZExtValue();
+
+ return true;
+}
+
/// \brief Scale down both weights to fit into uint32_t.
static void scaleWeights(uint64_t &NewTrue, uint64_t &NewFalse) {
uint64_t NewMax = (NewTrue > NewFalse) ? NewTrue : NewFalse;
@@ -3942,7 +3963,7 @@
// Another choice is to assume TrueProb for BB1 equals to TrueProb for
// TmpBB, but the math is more complicated.
uint64_t TrueWeight, FalseWeight;
- if (Br1->getBranchWeights(TrueWeight, FalseWeight)) {
+ if (extractBranchMetadata(Br1, TrueWeight, FalseWeight)) {
uint64_t NewTrueWeight = TrueWeight;
uint64_t NewFalseWeight = TrueWeight + 2 * FalseWeight;
scaleWeights(NewTrueWeight, NewFalseWeight);
@@ -3975,7 +3996,7 @@
// assumes that
// FalseProb for BB1 == TrueProb for BB1 * FalseProb for TmpBB.
uint64_t TrueWeight, FalseWeight;
- if (Br1->getBranchWeights(TrueWeight, FalseWeight)) {
+ if (extractBranchMetadata(Br1, TrueWeight, FalseWeight)) {
uint64_t NewTrueWeight = 2 * TrueWeight + FalseWeight;
uint64_t NewFalseWeight = FalseWeight;
scaleWeights(NewTrueWeight, NewFalseWeight);