Remove duplicate successors from indirectbr instructions before building the machine CFG.

This makes early tail duplication run 60 times faster when compiling the Firefox
JavaScript interpreter, see PR6186.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95831 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2010-02-11 00:34:18 +00:00
parent be905e26f6
commit 598b24c6d1

View File

@ -2062,9 +2062,15 @@ void SelectionDAGBuilder::visitSwitch(SwitchInst &SI) {
} }
void SelectionDAGBuilder::visitIndirectBr(IndirectBrInst &I) { void SelectionDAGBuilder::visitIndirectBr(IndirectBrInst &I) {
// Update machine-CFG edges. // Update machine-CFG edges with unique successors.
std::vector<BasicBlock*> succs;
succs.reserve(I.getNumSuccessors());
for (unsigned i = 0, e = I.getNumSuccessors(); i != e; ++i) for (unsigned i = 0, e = I.getNumSuccessors(); i != e; ++i)
CurMBB->addSuccessor(FuncInfo.MBBMap[I.getSuccessor(i)]); succs.push_back(I.getSuccessor(i));
std::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)
CurMBB->addSuccessor(FuncInfo.MBBMap[succs[i]]);
DAG.setRoot(DAG.getNode(ISD::BRIND, getCurDebugLoc(), DAG.setRoot(DAG.getNode(ISD::BRIND, getCurDebugLoc(),
MVT::Other, getControlRoot(), MVT::Other, getControlRoot(),