diff options
| -rw-r--r-- | lib/CodeGen/PreAllocSplitting.cpp | 49 |
1 files changed, 12 insertions, 37 deletions
diff --git a/lib/CodeGen/PreAllocSplitting.cpp b/lib/CodeGen/PreAllocSplitting.cpp index 5dc14e146f..8cbc8c224a 100644 --- a/lib/CodeGen/PreAllocSplitting.cpp +++ b/lib/CodeGen/PreAllocSplitting.cpp @@ -481,32 +481,21 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI, // Search for the use in this block that precedes the instruction we care // about, going to the fallback case if we don't find it. - if (UseI == MBB->begin()) - return PerformPHIConstructionFallBack(UseI, MBB, LI, Visited, Defs, - Uses, NewVNs, LiveOut, Phis, - IsTopLevel, IsIntraBlock); - MachineBasicBlock::iterator Walker = UseI; - --Walker; bool found = false; while (Walker != MBB->begin()) { + --Walker; if (BlockUses.count(Walker)) { found = true; break; } - --Walker; - } - - // Must check begin() too. - if (!found) { - if (BlockUses.count(Walker)) - found = true; - else - return PerformPHIConstructionFallBack(UseI, MBB, LI, Visited, Defs, - Uses, NewVNs, LiveOut, Phis, - IsTopLevel, IsIntraBlock); } + if (!found) + return PerformPHIConstructionFallBack(UseI, MBB, LI, Visited, Defs, + Uses, NewVNs, LiveOut, Phis, + IsTopLevel, IsIntraBlock); + SlotIndex UseIndex = LIs->getInstructionIndex(Walker); UseIndex = UseIndex.getUseIndex(); SlotIndex EndIndex; @@ -533,17 +522,11 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI, // This case is basically a merging of the two preceding case, with the // special note that checking for defs must take precedence over checking // for uses, because of two-address instructions. - - if (UseI == MBB->begin()) - return PerformPHIConstructionFallBack(UseI, MBB, LI, Visited, Defs, Uses, - NewVNs, LiveOut, Phis, - IsTopLevel, IsIntraBlock); - MachineBasicBlock::iterator Walker = UseI; - --Walker; bool foundDef = false; bool foundUse = false; while (Walker != MBB->begin()) { + --Walker; if (BlockDefs.count(Walker)) { foundDef = true; break; @@ -551,21 +534,13 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI, foundUse = true; break; } - --Walker; - } - - // Must check begin() too. - if (!foundDef && !foundUse) { - if (BlockDefs.count(Walker)) - foundDef = true; - else if (BlockUses.count(Walker)) - foundUse = true; - else - return PerformPHIConstructionFallBack(UseI, MBB, LI, Visited, Defs, - Uses, NewVNs, LiveOut, Phis, - IsTopLevel, IsIntraBlock); } + if (!foundDef && !foundUse) + return PerformPHIConstructionFallBack(UseI, MBB, LI, Visited, Defs, + Uses, NewVNs, LiveOut, Phis, + IsTopLevel, IsIntraBlock); + SlotIndex StartIndex = LIs->getInstructionIndex(Walker); StartIndex = foundDef ? StartIndex.getDefIndex() : StartIndex.getUseIndex(); SlotIndex EndIndex; |