Introduce MachineBranchProbabilityInfo class, which has similar API to
BranchProbabilityInfo (expect setEdgeWeight which is not available here).
Branch Weights are kept in MachineBasicBlocks. To turn off this analysis
set -use-mbpi=false.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133184 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 4e19d2b..d79a5ae 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -1279,6 +1279,24 @@
return true;
}
+/// Return branch probability calculated by BranchProbabilityInfo for IR blocks.
+uint32_t SelectionDAGBuilder::getEdgeWeight(MachineBasicBlock *Src,
+ MachineBasicBlock *Dst) {
+ BranchProbabilityInfo *BPI = FuncInfo.BPI;
+ if (!BPI)
+ return 0;
+ BasicBlock *SrcBB = const_cast<BasicBlock*>(Src->getBasicBlock());
+ BasicBlock *DstBB = const_cast<BasicBlock*>(Dst->getBasicBlock());
+ return BPI->getEdgeWeight(SrcBB, DstBB);
+}
+
+void SelectionDAGBuilder::addSuccessorWithWeight(MachineBasicBlock *Src,
+ MachineBasicBlock *Dst) {
+ uint32_t weight = getEdgeWeight(Src, Dst);
+ Src->addSuccessor(Dst, weight);
+}
+
+
static bool InBlock(const Value *V, const BasicBlock *BB) {
if (const Instruction *I = dyn_cast<Instruction>(V))
return I->getParent() == BB;
@@ -1548,8 +1566,8 @@
}
// Update successor info
- SwitchBB->addSuccessor(CB.TrueBB);
- SwitchBB->addSuccessor(CB.FalseBB);
+ addSuccessorWithWeight(SwitchBB, CB.TrueBB);
+ addSuccessorWithWeight(SwitchBB, CB.FalseBB);
// Set NextBlock to be the MBB immediately after the current one, if any.
// This is used to avoid emitting unnecessary branches to the next block.
@@ -1693,8 +1711,8 @@
MachineBasicBlock* MBB = B.Cases[0].ThisBB;
- SwitchBB->addSuccessor(B.Default);
- SwitchBB->addSuccessor(MBB);
+ addSuccessorWithWeight(SwitchBB, B.Default);
+ addSuccessorWithWeight(SwitchBB, MBB);
SDValue BrRange = DAG.getNode(ISD::BRCOND, getCurDebugLoc(),
MVT::Other, CopyTo, RangeCmp,
@@ -1739,8 +1757,8 @@
ISD::SETNE);
}
- SwitchBB->addSuccessor(B.TargetBB);
- SwitchBB->addSuccessor(NextMBB);
+ addSuccessorWithWeight(SwitchBB, B.TargetBB);
+ addSuccessorWithWeight(SwitchBB, NextMBB);
SDValue BrAnd = DAG.getNode(ISD::BRCOND, getCurDebugLoc(),
MVT::Other, getControlRoot(),
@@ -1980,8 +1998,9 @@
// table.
MachineBasicBlock *JumpTableBB = CurMF->CreateMachineBasicBlock(LLVMBB);
CurMF->insert(BBI, JumpTableBB);
- CR.CaseBB->addSuccessor(Default);
- CR.CaseBB->addSuccessor(JumpTableBB);
+
+ addSuccessorWithWeight(CR.CaseBB, Default);
+ addSuccessorWithWeight(CR.CaseBB, JumpTableBB);
// Build a vector of destination BBs, corresponding to each target
// of the jump table. If the value of the jump table slot corresponds to
@@ -2008,7 +2027,7 @@
E = DestBBs.end(); I != E; ++I) {
if (!SuccsHandled[(*I)->getNumber()]) {
SuccsHandled[(*I)->getNumber()] = true;
- JumpTableBB->addSuccessor(*I);
+ addSuccessorWithWeight(JumpTableBB, *I);
}
}
@@ -2427,8 +2446,10 @@
succs.push_back(I.getSuccessor(i));
array_pod_sort(succs.begin(), succs.end());
succs.erase(std::unique(succs.begin(), succs.end()), succs.end());
- for (unsigned i = 0, e = succs.size(); i != e; ++i)
- IndirectBrMBB->addSuccessor(FuncInfo.MBBMap[succs[i]]);
+ for (unsigned i = 0, e = succs.size(); i != e; ++i) {
+ MachineBasicBlock *Succ = FuncInfo.MBBMap[succs[i]];
+ addSuccessorWithWeight(IndirectBrMBB, Succ);
+ }
DAG.setRoot(DAG.getNode(ISD::BRIND, getCurDebugLoc(),
MVT::Other, getControlRoot(),