Add more debugging output.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126158 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2011-02-21 23:39:48 +00:00
parent d45e8bf93b
commit cf13af6fde

View File

@ -501,10 +501,11 @@ static bool ProfitableToMerge(MachineBasicBlock *MBB1,
MachineBasicBlock *SuccBB, MachineBasicBlock *SuccBB,
MachineBasicBlock *PredBB) { MachineBasicBlock *PredBB) {
CommonTailLen = ComputeCommonTailLength(MBB1, MBB2, I1, I2); CommonTailLen = ComputeCommonTailLength(MBB1, MBB2, I1, I2);
MachineFunction *MF = MBB1->getParent();
if (CommonTailLen == 0) if (CommonTailLen == 0)
return false; return false;
DEBUG(dbgs() << "Common tail length of BB#" << MBB1->getNumber()
<< " and BB#" << MBB2->getNumber() << " is " << CommonTailLen
<< '\n');
// It's almost always profitable to merge any number of non-terminator // It's almost always profitable to merge any number of non-terminator
// instructions with the block that falls through into the common successor. // instructions with the block that falls through into the common successor.
@ -541,6 +542,7 @@ static bool ProfitableToMerge(MachineBasicBlock *MBB1,
// we don't have to split a block. At worst we will be introducing 1 new // we don't have to split a block. At worst we will be introducing 1 new
// branch instruction, which is likely to be smaller than the 2 // branch instruction, which is likely to be smaller than the 2
// instructions that would be deleted in the merge. // instructions that would be deleted in the merge.
MachineFunction *MF = MBB1->getParent();
if (EffectiveTailLen >= 2 && if (EffectiveTailLen >= 2 &&
MF->getFunction()->hasFnAttr(Attribute::OptimizeForSize) && MF->getFunction()->hasFnAttr(Attribute::OptimizeForSize) &&
(I1 == MBB1->begin() || I2 == MBB2->begin())) (I1 == MBB1->begin() || I2 == MBB2->begin()))