Require and preserve LoopInfo for early if-conversion.

It will surely be needed by heuristics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160027 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2012-07-10 22:39:56 +00:00
parent 4e996de58c
commit 47730a774d

View File

@ -27,6 +27,7 @@
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineLoopInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Target/TargetInstrInfo.h"
@ -513,6 +514,7 @@ class EarlyIfConverter : public MachineFunctionPass {
const TargetRegisterInfo *TRI;
MachineRegisterInfo *MRI;
MachineDominatorTree *DomTree;
MachineLoopInfo *Loops;
SSAIfConv IfConv;
public:
@ -524,6 +526,7 @@ public:
private:
bool tryConvertIf(MachineBasicBlock*);
void updateDomTree(ArrayRef<MachineBasicBlock*> Removed);
void updateLoops(ArrayRef<MachineBasicBlock*> Removed);
};
} // end anonymous namespace
@ -541,6 +544,8 @@ void EarlyIfConverter::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<MachineBranchProbabilityInfo>();
AU.addRequired<MachineDominatorTree>();
AU.addPreserved<MachineDominatorTree>();
AU.addRequired<MachineLoopInfo>();
AU.addPreserved<MachineLoopInfo>();
MachineFunctionPass::getAnalysisUsage(AU);
}
@ -561,6 +566,16 @@ void EarlyIfConverter::updateDomTree(ArrayRef<MachineBasicBlock*> Removed) {
}
}
/// Update LoopInfo after if-conversion.
void EarlyIfConverter::updateLoops(ArrayRef<MachineBasicBlock*> Removed) {
if (!Loops)
return;
// If-conversion doesn't change loop structure, and it doesn't mess with back
// edges, so updating LoopInfo is simply removing the dead blocks.
for (unsigned i = 0, e = Removed.size(); i != e; ++i)
Loops->removeBlock(Removed[i]);
}
/// Attempt repeated if-conversion on MBB, return true if successful.
///
bool EarlyIfConverter::tryConvertIf(MachineBasicBlock *MBB) {
@ -571,6 +586,7 @@ bool EarlyIfConverter::tryConvertIf(MachineBasicBlock *MBB) {
IfConv.convertIf(RemovedBlocks);
Changed = true;
updateDomTree(RemovedBlocks);
updateLoops(RemovedBlocks);
}
return Changed;
}
@ -583,6 +599,7 @@ bool EarlyIfConverter::runOnMachineFunction(MachineFunction &MF) {
TRI = MF.getTarget().getRegisterInfo();
MRI = &MF.getRegInfo();
DomTree = &getAnalysis<MachineDominatorTree>();
Loops = getAnalysisIfAvailable<MachineLoopInfo>();
bool Changed = false;
IfConv.runOnMachineFunction(MF);