Add an option to disable critical edge splitting in PHIElimination.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127398 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Cameron Zwarich 2011-03-10 05:59:17 +00:00
parent 2f5565d21c
commit 6a951ac63f

View File

@ -28,12 +28,18 @@
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include <algorithm>
#include <map>
using namespace llvm;
static cl::opt<bool>
DisableEdgeSplitting("disable-phi-elim-edge-splitting", cl::init(false),
cl::Hidden, cl::desc("Disable critical edge splitting "
"during PHI elimination"));
namespace {
class PHIElimination : public MachineFunctionPass {
MachineRegisterInfo *MRI; // Machine register information
@ -105,10 +111,12 @@ bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
bool Changed = false;
// Split critical edges to help the coalescer
if (LiveVariables *LV = getAnalysisIfAvailable<LiveVariables>()) {
MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
Changed |= SplitPHIEdges(MF, *I, *LV, MLI);
if (!DisableEdgeSplitting) {
if (LiveVariables *LV = getAnalysisIfAvailable<LiveVariables>()) {
MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
Changed |= SplitPHIEdges(MF, *I, *LV, MLI);
}
}
// Populate VRegPHIUseCount