//
//===----------------------------------------------------------------------===//
+#include "llvm/Constants.h"
+#include "llvm/Function.h"
#include "llvm/Instructions.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/Metadata.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
-#include <climits>
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Support/CFG.h"
+#include "llvm/Support/Debug.h"
using namespace llvm;
char BranchProbabilityInfo::ID = 0;
-
+namespace {
// Please note that BranchProbabilityAnalysis is not a FunctionPass.
// It is created by BranchProbabilityInfo (which is a FunctionPass), which
// provides a clear interface. Thanks to that, all heuristics and other
// private methods are hidden in the .cpp file.
class BranchProbabilityAnalysis {
- typedef std::pair<BasicBlock *, BasicBlock *> Edge;
-
- DenseMap<Edge, unsigned> *Weights;
+ typedef std::pair<const BasicBlock *, const BasicBlock *> Edge;
BranchProbabilityInfo *BP;
// V
// BB1<-+
// | |
- // | | (Weight = 128)
+ // | | (Weight = 124)
// V |
// BB2--+
// |
// V
// BB3
//
- // Probability of the edge BB2->BB1 = 128 / (128 + 4) = 0.9696..
- // Probability of the edge BB2->BB3 = 4 / (128 + 4) = 0.0303..
+ // Probability of the edge BB2->BB1 = 124 / (124 + 4) = 0.96875
+ // Probability of the edge BB2->BB3 = 4 / (124 + 4) = 0.03125
+
+ static const uint32_t LBH_TAKEN_WEIGHT = 124;
+ static const uint32_t LBH_NONTAKEN_WEIGHT = 4;
+
+ static const uint32_t RH_TAKEN_WEIGHT = 24;
+ static const uint32_t RH_NONTAKEN_WEIGHT = 8;
- static const unsigned int LBH_TAKEN_WEIGHT = 128;
- static const unsigned int LBH_NONTAKEN_WEIGHT = 4;
+ static const uint32_t PH_TAKEN_WEIGHT = 20;
+ static const uint32_t PH_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;
// Standard weight value. Used when none of the heuristics set weight for
// the edge.
- static const unsigned int NORMAL_WEIGHT = 16;
+ static const uint32_t NORMAL_WEIGHT = 16;
// Minimum weight of an edge. Please note, that weight is NEVER 0.
- static const unsigned int MIN_WEIGHT = 1;
+ static const uint32_t MIN_WEIGHT = 1;
// Return TRUE if BB leads directly to a Return Instruction.
static bool isReturningBlock(BasicBlock *BB) {
return false;
}
- // Multiply Edge Weight by two.
- void incEdgeWeight(BasicBlock *Src, BasicBlock *Dst) {
- unsigned Weight = BP->getEdgeWeight(Src, Dst);
- unsigned MaxWeight = getMaxWeightFor(Src);
-
- if (Weight * 2 > MaxWeight)
- BP->setEdgeWeight(Src, Dst, MaxWeight);
- else
- BP->setEdgeWeight(Src, Dst, Weight * 2);
- }
-
- // Divide Edge Weight by two.
- void decEdgeWeight(BasicBlock *Src, BasicBlock *Dst) {
- unsigned Weight = BP->getEdgeWeight(Src, Dst);
-
- assert(Weight > 0);
- if (Weight / 2 < MIN_WEIGHT)
- BP->setEdgeWeight(Src, Dst, MIN_WEIGHT);
- else
- BP->setEdgeWeight(Src, Dst, Weight / 2);
- }
-
-
- unsigned getMaxWeightFor(BasicBlock *BB) const {
- return UINT_MAX / BB->getTerminator()->getNumSuccessors();
+ uint32_t getMaxWeightFor(BasicBlock *BB) const {
+ return UINT32_MAX / BB->getTerminator()->getNumSuccessors();
}
public:
- BranchProbabilityAnalysis(DenseMap<Edge, unsigned> *W,
- BranchProbabilityInfo *BP, LoopInfo *LI)
- : Weights(W), BP(BP), LI(LI) {
+ BranchProbabilityAnalysis(BranchProbabilityInfo *BP, LoopInfo *LI)
+ : BP(BP), LI(LI) {
}
+ // Metadata Weights
+ bool calcMetadataWeights(BasicBlock *BB);
+
// Return Heuristics
- void calcReturnHeuristics(BasicBlock *BB);
+ bool calcReturnHeuristics(BasicBlock *BB);
// Pointer Heuristics
- void calcPointerHeuristics(BasicBlock *BB);
+ bool calcPointerHeuristics(BasicBlock *BB);
// Loop Branch Heuristics
- void calcLoopBranchHeuristics(BasicBlock *BB);
+ bool calcLoopBranchHeuristics(BasicBlock *BB);
+
+ // Zero Heuristics
+ bool calcZeroHeuristics(BasicBlock *BB);
+
+ // Floating Point Heuristics
+ bool calcFloatingPointHeuristics(BasicBlock *BB);
bool runOnFunction(Function &F);
};
+} // end anonymous namespace
+
+// Propagate existing explicit probabilities from either profile data or
+// 'expect' intrinsic processing.
+bool BranchProbabilityAnalysis::calcMetadataWeights(BasicBlock *BB) {
+ TerminatorInst *TI = BB->getTerminator();
+ if (TI->getNumSuccessors() == 1)
+ return false;
+ if (!isa<BranchInst>(TI) && !isa<SwitchInst>(TI))
+ return false;
+
+ MDNode *WeightsNode = TI->getMetadata(LLVMContext::MD_prof);
+ if (!WeightsNode)
+ return false;
+
+ // Ensure there are weights for all of the successors. Note that the first
+ // operand to the metadata node is a name, not a weight.
+ if (WeightsNode->getNumOperands() != TI->getNumSuccessors() + 1)
+ return false;
+
+ // Build up the final weights that will be used in a temporary buffer, but
+ // don't add them until all weihts are present. Each weight value is clamped
+ // to [1, getMaxWeightFor(BB)].
+ uint32_t WeightLimit = getMaxWeightFor(BB);
+ SmallVector<uint32_t, 2> Weights;
+ Weights.reserve(TI->getNumSuccessors());
+ for (unsigned i = 1, e = WeightsNode->getNumOperands(); i != e; ++i) {
+ ConstantInt *Weight = dyn_cast<ConstantInt>(WeightsNode->getOperand(i));
+ if (!Weight)
+ return false;
+ Weights.push_back(
+ std::max<uint32_t>(1, Weight->getLimitedValue(WeightLimit)));
+ }
+ assert(Weights.size() == TI->getNumSuccessors() && "Checked above");
+ for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
+ BP->setEdgeWeight(BB, TI->getSuccessor(i), Weights[i]);
+
+ return true;
+}
// Calculate Edge Weights using "Return Heuristics". Predict a successor which
// leads directly to Return Instruction will not be taken.
-void BranchProbabilityAnalysis::calcReturnHeuristics(BasicBlock *BB){
+bool BranchProbabilityAnalysis::calcReturnHeuristics(BasicBlock *BB){
if (BB->getTerminator()->getNumSuccessors() == 1)
- return;
+ return false;
+
+ SmallPtrSet<BasicBlock *, 4> ReturningEdges;
+ SmallPtrSet<BasicBlock *, 4> StayEdges;
for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
BasicBlock *Succ = *I;
- if (isReturningBlock(Succ)) {
- decEdgeWeight(BB, Succ);
+ if (isReturningBlock(Succ))
+ ReturningEdges.insert(Succ);
+ else
+ StayEdges.insert(Succ);
+ }
+
+ if (uint32_t numStayEdges = StayEdges.size()) {
+ uint32_t stayWeight = RH_TAKEN_WEIGHT / numStayEdges;
+ if (stayWeight < NORMAL_WEIGHT)
+ stayWeight = NORMAL_WEIGHT;
+
+ for (SmallPtrSet<BasicBlock *, 4>::iterator I = StayEdges.begin(),
+ E = StayEdges.end(); I != E; ++I)
+ BP->setEdgeWeight(BB, *I, stayWeight);
+ }
+
+ if (uint32_t numRetEdges = ReturningEdges.size()) {
+ uint32_t retWeight = RH_NONTAKEN_WEIGHT / numRetEdges;
+ if (retWeight < MIN_WEIGHT)
+ retWeight = MIN_WEIGHT;
+ for (SmallPtrSet<BasicBlock *, 4>::iterator I = ReturningEdges.begin(),
+ E = ReturningEdges.end(); I != E; ++I) {
+ BP->setEdgeWeight(BB, *I, retWeight);
}
}
+
+ return ReturningEdges.size() > 0;
}
// Calculate Edge Weights using "Pointer Heuristics". Predict a comparsion
// between two pointer or pointer and NULL will fail.
-void BranchProbabilityAnalysis::calcPointerHeuristics(BasicBlock *BB) {
+bool BranchProbabilityAnalysis::calcPointerHeuristics(BasicBlock *BB) {
BranchInst * BI = dyn_cast<BranchInst>(BB->getTerminator());
if (!BI || !BI->isConditional())
- return;
+ return false;
Value *Cond = BI->getCondition();
ICmpInst *CI = dyn_cast<ICmpInst>(Cond);
- if (!CI)
- return;
+ if (!CI || !CI->isEquality())
+ return false;
Value *LHS = CI->getOperand(0);
if (!LHS->getType()->isPointerTy())
- return;
+ return false;
assert(CI->getOperand(1)->getType()->isPointerTy());
// p == 0 -> isProb = false
// p != q -> isProb = true
// p == q -> isProb = false;
- bool isProb = !CI->isEquality();
+ bool isProb = CI->getPredicate() == ICmpInst::ICMP_NE;
if (!isProb)
std::swap(Taken, NonTaken);
- incEdgeWeight(BB, Taken);
- decEdgeWeight(BB, NonTaken);
+ BP->setEdgeWeight(BB, Taken, PH_TAKEN_WEIGHT);
+ BP->setEdgeWeight(BB, NonTaken, PH_NONTAKEN_WEIGHT);
+ return true;
}
// Calculate Edge Weights using "Loop Branch Heuristics". Predict backedges
// as taken, exiting edges as not-taken.
-void BranchProbabilityAnalysis::calcLoopBranchHeuristics(BasicBlock *BB) {
- unsigned numSuccs = BB->getTerminator()->getNumSuccessors();
+bool BranchProbabilityAnalysis::calcLoopBranchHeuristics(BasicBlock *BB) {
+ uint32_t numSuccs = BB->getTerminator()->getNumSuccessors();
Loop *L = LI->getLoopFor(BB);
if (!L)
- return;
+ return false;
- SmallVector<BasicBlock *, 8> BackEdges;
- SmallVector<BasicBlock *, 8> ExitingEdges;
+ SmallPtrSet<BasicBlock *, 8> BackEdges;
+ SmallPtrSet<BasicBlock *, 8> ExitingEdges;
+ SmallPtrSet<BasicBlock *, 8> InEdges; // Edges from header to the loop.
+
+ bool isHeader = BB == L->getHeader();
for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
BasicBlock *Succ = *I;
Loop *SuccL = LI->getLoopFor(Succ);
if (SuccL != L)
- ExitingEdges.push_back(Succ);
+ ExitingEdges.insert(Succ);
else if (Succ == L->getHeader())
- BackEdges.push_back(Succ);
+ BackEdges.insert(Succ);
+ else if (isHeader)
+ InEdges.insert(Succ);
}
- if (unsigned numBackEdges = BackEdges.size()) {
- unsigned backWeight = LBH_TAKEN_WEIGHT / numBackEdges;
+ if (uint32_t numBackEdges = BackEdges.size()) {
+ uint32_t backWeight = LBH_TAKEN_WEIGHT / numBackEdges;
if (backWeight < NORMAL_WEIGHT)
backWeight = NORMAL_WEIGHT;
- for (SmallVector<BasicBlock *, 8>::iterator EI = BackEdges.begin(),
+ for (SmallPtrSet<BasicBlock *, 8>::iterator EI = BackEdges.begin(),
EE = BackEdges.end(); EI != EE; ++EI) {
BasicBlock *Back = *EI;
BP->setEdgeWeight(BB, Back, backWeight);
}
}
- unsigned numExitingEdges = ExitingEdges.size();
- if (unsigned numNonExitingEdges = numSuccs - numExitingEdges) {
- unsigned exitWeight = LBH_NONTAKEN_WEIGHT / numNonExitingEdges;
+ if (uint32_t numInEdges = InEdges.size()) {
+ uint32_t inWeight = LBH_TAKEN_WEIGHT / numInEdges;
+ if (inWeight < NORMAL_WEIGHT)
+ inWeight = NORMAL_WEIGHT;
+
+ for (SmallPtrSet<BasicBlock *, 8>::iterator EI = InEdges.begin(),
+ EE = InEdges.end(); EI != EE; ++EI) {
+ BasicBlock *Back = *EI;
+ BP->setEdgeWeight(BB, Back, inWeight);
+ }
+ }
+
+ uint32_t numExitingEdges = ExitingEdges.size();
+ if (uint32_t numNonExitingEdges = numSuccs - numExitingEdges) {
+ uint32_t exitWeight = LBH_NONTAKEN_WEIGHT / numNonExitingEdges;
if (exitWeight < MIN_WEIGHT)
exitWeight = MIN_WEIGHT;
- for (SmallVector<BasicBlock *, 8>::iterator EI = ExitingEdges.begin(),
+ for (SmallPtrSet<BasicBlock *, 8>::iterator EI = ExitingEdges.begin(),
EE = ExitingEdges.end(); EI != EE; ++EI) {
BasicBlock *Exiting = *EI;
BP->setEdgeWeight(BB, Exiting, exitWeight);
}
}
+
+ return true;
}
-bool BranchProbabilityAnalysis::runOnFunction(Function &F) {
+bool BranchProbabilityAnalysis::calcZeroHeuristics(BasicBlock *BB) {
+ BranchInst * BI = dyn_cast<BranchInst>(BB->getTerminator());
+ if (!BI || !BI->isConditional())
+ return false;
- for (Function::iterator I = F.begin(), E = F.end(); I != E; ) {
- BasicBlock *BB = I++;
+ Value *Cond = BI->getCondition();
+ ICmpInst *CI = dyn_cast<ICmpInst>(Cond);
+ if (!CI)
+ return false;
- // Only LBH uses setEdgeWeight method.
- calcLoopBranchHeuristics(BB);
+ Value *RHS = CI->getOperand(1);
+ ConstantInt *CV = dyn_cast<ConstantInt>(RHS);
+ if (!CV)
+ return false;
- // PH and RH use only incEdgeWeight and decEwdgeWeight methods to
- // not efface LBH results.
- calcPointerHeuristics(BB);
- calcReturnHeuristics(BB);
+ bool isProb;
+ if (CV->isZero()) {
+ switch (CI->getPredicate()) {
+ case CmpInst::ICMP_EQ:
+ // X == 0 -> Unlikely
+ isProb = false;
+ break;
+ case CmpInst::ICMP_NE:
+ // X != 0 -> Likely
+ isProb = true;
+ break;
+ case CmpInst::ICMP_SLT:
+ // X < 0 -> Unlikely
+ isProb = false;
+ break;
+ case CmpInst::ICMP_SGT:
+ // X > 0 -> Likely
+ isProb = true;
+ break;
+ default:
+ return false;
+ }
+ } else if (CV->isOne() && CI->getPredicate() == CmpInst::ICMP_SLT) {
+ // InstCombine canonicalizes X <= 0 into X < 1.
+ // X <= 0 -> Unlikely
+ isProb = false;
+ } else if (CV->isAllOnesValue() && CI->getPredicate() == CmpInst::ICMP_SGT) {
+ // InstCombine canonicalizes X >= 0 into X > -1.
+ // X >= 0 -> Likely
+ isProb = true;
+ } else {
+ return false;
}
+ BasicBlock *Taken = BI->getSuccessor(0);
+ BasicBlock *NonTaken = BI->getSuccessor(1);
+
+ if (!isProb)
+ std::swap(Taken, NonTaken);
+
+ BP->setEdgeWeight(BB, Taken, ZH_TAKEN_WEIGHT);
+ BP->setEdgeWeight(BB, NonTaken, ZH_NONTAKEN_WEIGHT);
+
+ return true;
+}
+
+bool BranchProbabilityAnalysis::calcFloatingPointHeuristics(BasicBlock *BB) {
+ BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator());
+ if (!BI || !BI->isConditional())
+ return false;
+
+ Value *Cond = BI->getCondition();
+ FCmpInst *FCmp = dyn_cast<FCmpInst>(Cond);
+ if (!FCmp)
+ return false;
+
+ bool isProb;
+ if (FCmp->isEquality()) {
+ // f1 == f2 -> Unlikely
+ // f1 != f2 -> Likely
+ isProb = !FCmp->isTrueWhenEqual();
+ } else if (FCmp->getPredicate() == FCmpInst::FCMP_ORD) {
+ // !isnan -> Likely
+ isProb = true;
+ } else if (FCmp->getPredicate() == FCmpInst::FCMP_UNO) {
+ // isnan -> Unlikely
+ isProb = false;
+ } else {
+ return false;
+ }
+
+ BasicBlock *Taken = BI->getSuccessor(0);
+ BasicBlock *NonTaken = BI->getSuccessor(1);
+
+ if (!isProb)
+ std::swap(Taken, NonTaken);
+
+ BP->setEdgeWeight(BB, Taken, FPH_TAKEN_WEIGHT);
+ BP->setEdgeWeight(BB, NonTaken, FPH_NONTAKEN_WEIGHT);
+
+ return true;
+}
+
+bool BranchProbabilityAnalysis::runOnFunction(Function &F) {
+ for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) {
+ if (calcMetadataWeights(I))
+ continue;
+ if (calcLoopBranchHeuristics(I))
+ continue;
+ if (calcReturnHeuristics(I))
+ continue;
+ if (calcPointerHeuristics(I))
+ continue;
+ if (calcZeroHeuristics(I))
+ continue;
+ calcFloatingPointHeuristics(I);
+ }
return false;
}
+void BranchProbabilityInfo::getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<LoopInfo>();
+ AU.setPreservesAll();
+}
bool BranchProbabilityInfo::runOnFunction(Function &F) {
+ LastF = &F; // Store the last function we ran on for printing.
LoopInfo &LI = getAnalysis<LoopInfo>();
- BranchProbabilityAnalysis BPA(&Weights, this, &LI);
- bool ret = BPA.runOnFunction(F);
- return ret;
+ BranchProbabilityAnalysis BPA(this, &LI);
+ return BPA.runOnFunction(F);
}
-// TODO: This currently hardcodes 80% as a fraction 4/5. We will soon add a
-// BranchProbability class to encapsulate the fractional probability and
-// define a few static instances of the class for use as predefined thresholds.
-bool BranchProbabilityInfo::isEdgeHot(BasicBlock *Src, BasicBlock *Dst) const {
- unsigned Sum = 0;
- for (succ_iterator I = succ_begin(Src), E = succ_end(Src); I != E; ++I) {
- BasicBlock *Succ = *I;
- unsigned Weight = getEdgeWeight(Src, Succ);
- unsigned PrevSum = Sum;
+void BranchProbabilityInfo::print(raw_ostream &OS, const Module *) const {
+ OS << "---- Branch Probabilities ----\n";
+ // We print the probabilities from the last function the analysis ran over,
+ // or the function it is currently running over.
+ assert(LastF && "Cannot print prior to running over a function");
+ for (Function::const_iterator BI = LastF->begin(), BE = LastF->end();
+ BI != BE; ++BI) {
+ for (succ_const_iterator SI = succ_begin(BI), SE = succ_end(BI);
+ SI != SE; ++SI) {
+ printEdgeProbability(OS << " ", BI, *SI);
+ }
+ }
+}
+
+uint32_t BranchProbabilityInfo::getSumForBlock(const BasicBlock *BB) const {
+ uint32_t Sum = 0;
+
+ for (succ_const_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
+ const BasicBlock *Succ = *I;
+ uint32_t Weight = getEdgeWeight(BB, Succ);
+ uint32_t PrevSum = Sum;
Sum += Weight;
assert(Sum > PrevSum); (void) PrevSum;
}
- return getEdgeWeight(Src, Dst) * 5 > Sum * 4;
+ return Sum;
+}
+
+bool BranchProbabilityInfo::
+isEdgeHot(const BasicBlock *Src, const BasicBlock *Dst) const {
+ // Hot probability is at least 4/5 = 80%
+ // FIXME: Compare against a static "hot" BranchProbability.
+ return getEdgeProbability(Src, Dst) > BranchProbability(4, 5);
}
BasicBlock *BranchProbabilityInfo::getHotSucc(BasicBlock *BB) const {
- unsigned Sum = 0;
- unsigned MaxWeight = 0;
+ uint32_t Sum = 0;
+ uint32_t MaxWeight = 0;
BasicBlock *MaxSucc = 0;
for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) {
BasicBlock *Succ = *I;
- unsigned Weight = getEdgeWeight(BB, Succ);
- unsigned PrevSum = Sum;
+ uint32_t Weight = getEdgeWeight(BB, Succ);
+ uint32_t PrevSum = Sum;
Sum += Weight;
assert(Sum > PrevSum); (void) PrevSum;
}
}
- if (MaxWeight * 5 > Sum * 4)
+ // Hot probability is at least 4/5 = 80%
+ if (BranchProbability(MaxWeight, Sum) > BranchProbability(4, 5))
return MaxSucc;
return 0;
}
// Return edge's weight. If can't find it, return DEFAULT_WEIGHT value.
-unsigned
-BranchProbabilityInfo::getEdgeWeight(BasicBlock *Src, BasicBlock *Dst) const {
+uint32_t BranchProbabilityInfo::
+getEdgeWeight(const BasicBlock *Src, const BasicBlock *Dst) const {
Edge E(Src, Dst);
- DenseMap<Edge, unsigned>::const_iterator I = Weights.find(E);
+ DenseMap<Edge, uint32_t>::const_iterator I = Weights.find(E);
if (I != Weights.end())
return I->second;
return DEFAULT_WEIGHT;
}
-void BranchProbabilityInfo::setEdgeWeight(BasicBlock *Src, BasicBlock *Dst,
- unsigned Weight) {
+void BranchProbabilityInfo::
+setEdgeWeight(const BasicBlock *Src, const BasicBlock *Dst, uint32_t Weight) {
Weights[std::make_pair(Src, Dst)] = Weight;
- DEBUG(dbgs() << "setEdgeWeight: " << Src->getNameStr() << " -> "
- << Dst->getNameStr() << " to " << Weight
- << (isEdgeHot(Src, Dst) ? " [is HOT now]\n" : "\n"));
+ DEBUG(dbgs() << "set edge " << Src->getNameStr() << " -> "
+ << Dst->getNameStr() << " weight to " << Weight
+ << (isEdgeHot(Src, Dst) ? " [is HOT now]\n" : "\n"));
}
-raw_ostream &
-BranchProbabilityInfo::printEdgeProbability(raw_ostream &OS, BasicBlock *Src,
- BasicBlock *Dst) const {
- unsigned Sum = 0;
- for (succ_iterator I = succ_begin(Src), E = succ_end(Src); I != E; ++I) {
- BasicBlock *Succ = *I;
- unsigned Weight = getEdgeWeight(Src, Succ);
- unsigned PrevSum = Sum;
+BranchProbability BranchProbabilityInfo::
+getEdgeProbability(const BasicBlock *Src, const BasicBlock *Dst) const {
- Sum += Weight;
- assert(Sum > PrevSum); (void) PrevSum;
- }
+ uint32_t N = getEdgeWeight(Src, Dst);
+ uint32_t D = getSumForBlock(Src);
- double Prob = (double)getEdgeWeight(Src, Dst) / Sum;
- OS << "probability (" << Src->getNameStr() << " --> " << Dst->getNameStr()
- << ") = " << Prob << "\n";
+ return BranchProbability(N, D);
+}
+
+raw_ostream &
+BranchProbabilityInfo::printEdgeProbability(raw_ostream &OS,
+ const BasicBlock *Src,
+ const BasicBlock *Dst) const {
+
+ const BranchProbability Prob = getEdgeProbability(Src, Dst);
+ OS << "edge " << Src->getNameStr() << " -> " << Dst->getNameStr()
+ << " probability is " << Prob
+ << (isEdgeHot(Src, Dst) ? " [HOT edge]\n" : "\n");
return OS;
}
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