diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp b/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp index 0d35b295a39..ac19f48e651 100644 --- a/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -1148,12 +1148,14 @@ SimpleRegisterCoalescing::isWinToJoinCrossClass(unsigned LargeReg, LiveInterval &SmallInt = li_->getInterval(SmallReg); unsigned LargeSize = li_->getApproximateInstructionCount(LargeInt); unsigned SmallSize = li_->getApproximateInstructionCount(SmallInt); - if (SmallSize > Threshold || LargeSize > Threshold) - if ((float)std::distance(mri_->use_nodbg_begin(SmallReg), - mri_->use_nodbg_end()) / SmallSize < - (float)std::distance(mri_->use_nodbg_begin(LargeReg), - mri_->use_nodbg_end()) / LargeSize) + if (LargeSize > Threshold) { + unsigned SmallUses = std::distance(mri_->use_nodbg_begin(SmallReg), + mri_->use_nodbg_end()); + unsigned LargeUses = std::distance(mri_->use_nodbg_begin(LargeReg), + mri_->use_nodbg_end()); + if (SmallUses*LargeSize < LargeUses*SmallSize) return false; + } return true; } @@ -1561,7 +1563,10 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) { (isExtSubReg || DstRC->isASubClass()) && !isWinToJoinCrossClass(LargeReg, SmallReg, allocatableRCRegs_[NewRC].count())) { - DEBUG(dbgs() << "\tSrc/Dest are different register classes.\n"); + DEBUG(dbgs() << "\tSrc/Dest are different register classes: " + << SrcRC->getName() << "/" + << DstRC->getName() << " -> " + << NewRC->getName() << ".\n"); // Allow the coalescer to try again in case either side gets coalesced to // a physical register that's compatible with the other side. e.g. // r1024 = MOV32to32_ r1025 |
