Preserve LiveVariables when doing critical edge splitting.

llvm-svn: 44063
This commit is contained in:
Owen Anderson 2007-11-13 20:04:45 +00:00
parent c54d8462fb
commit 569ef71e44
1 changed files with 13 additions and 2 deletions

View File

@ -26,6 +26,7 @@
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/ADT/Statistic.h"
@ -296,12 +297,15 @@ void StrongPHIElimination::processBlock(MachineBasicBlock* MBB) {
}
}
/// breakCriticalEdges - Break critical edges coming into blocks with PHI
/// nodes, preserving dominator and livevariable info.
void StrongPHIElimination::breakCriticalEdges(MachineFunction &Fn) {
typedef std::pair<MachineBasicBlock*, MachineBasicBlock*> MBB_pair;
MachineDominatorTree& MDT = getAnalysis<MachineDominatorTree>();
//LiveVariables& LV = getAnalysis<LiveVariables>();
LiveVariables& LV = getAnalysis<LiveVariables>();
// Find critical edges
std::vector<MBB_pair> criticals;
for (MachineFunction::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I)
if (!I->empty() &&
@ -314,9 +318,16 @@ void StrongPHIElimination::breakCriticalEdges(MachineFunction &Fn) {
for (std::vector<MBB_pair>::iterator I = criticals.begin(),
E = criticals.end(); I != E; ++I) {
SplitCriticalMachineEdge(I->first, I->second);
// Split the edge
MachineBasicBlock* new_bb = SplitCriticalMachineEdge(I->first, I->second);
// Update dominators
MDT.splitBlock(I->first);
// Update livevariables
for (unsigned var = 1024; var < Fn.getSSARegMap()->getLastVirtReg(); ++var)
if (isLiveOut(LV.getVarInfo(var), I->first))
LV.getVarInfo(var).AliveBlocks.set(new_bb->getNumber());
}
}