diff options
Diffstat (limited to 'lib/CodeGen/StrongPHIElimination.cpp')
| -rw-r--r-- | lib/CodeGen/StrongPHIElimination.cpp | 48 |
1 files changed, 32 insertions, 16 deletions
diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp index ee7228db7e..6467afe28f 100644 --- a/lib/CodeGen/StrongPHIElimination.cpp +++ b/lib/CodeGen/StrongPHIElimination.cpp @@ -51,9 +51,9 @@ namespace { // used as operands to another another PHI node std::set<unsigned> UsedByAnother; - // RenameSets are the sets of operands to a PHI (the defining instruction - // of the key) that can be renamed without copies - std::map<unsigned, std::set<unsigned> > RenameSets; + // RenameSets are the sets of operands (and their VNInfo IDs) to a PHI + // (the defining instruction of the key) that can be renamed without copies + std::map<unsigned, std::map<unsigned, unsigned> > RenameSets; // Store the DFS-in number of each block DenseMap<MachineBasicBlock*, unsigned> preorder; @@ -124,14 +124,15 @@ namespace { void computeDFS(MachineFunction& MF); void processBlock(MachineBasicBlock* MBB); - std::vector<DomForestNode*> computeDomForest(std::set<unsigned>& instrs, + std::vector<DomForestNode*> computeDomForest(std::map<unsigned, unsigned>& instrs, MachineRegisterInfo& MRI); void processPHIUnion(MachineInstr* Inst, - std::set<unsigned>& PHIUnion, + std::map<unsigned, unsigned>& PHIUnion, std::vector<StrongPHIElimination::DomForestNode*>& DF, std::vector<std::pair<unsigned, unsigned> >& locals); void ScheduleCopies(MachineBasicBlock* MBB, std::set<unsigned>& pushed); void InsertCopies(MachineBasicBlock* MBB, std::set<MachineBasicBlock*>& v); + void mergeLiveIntervals(unsigned primary, unsigned secondary, unsigned VN); }; char StrongPHIElimination::ID = 0; @@ -215,7 +216,7 @@ public: /// computeDomForest - compute the subforest of the DomTree corresponding /// to the defining blocks of the registers in question std::vector<StrongPHIElimination::DomForestNode*> -StrongPHIElimination::computeDomForest(std::set<unsigned>& regs, +StrongPHIElimination::computeDomForest(std::map<unsigned, unsigned>& regs, MachineRegisterInfo& MRI) { // Begin by creating a virtual root node, since the actual results // may well be a forest. Assume this node has maximum DFS-out number. @@ -225,9 +226,9 @@ StrongPHIElimination::computeDomForest(std::set<unsigned>& regs, // Populate a worklist with the registers std::vector<unsigned> worklist; worklist.reserve(regs.size()); - for (std::set<unsigned>::iterator I = regs.begin(), E = regs.end(); + for (std::map<unsigned, unsigned>::iterator I = regs.begin(), E = regs.end(); I != E; ++I) - worklist.push_back(*I); + worklist.push_back(I->first); // Sort the registers by the DFS-in number of their defining block PreorderSorter PS(preorder, MRI); @@ -408,7 +409,7 @@ void StrongPHIElimination::processBlock(MachineBasicBlock* MBB) { // are going to be renames rather than having copies inserted. This set // is refinded over the course of this function. UnionedBlocks is the set // of corresponding MBBs. - std::set<unsigned> PHIUnion; + std::map<unsigned, unsigned> PHIUnion; std::set<MachineBasicBlock*> UnionedBlocks; // Iterate over the operands of the PHI node @@ -442,7 +443,13 @@ void StrongPHIElimination::processBlock(MachineBasicBlock* MBB) { UsedByAnother.insert(SrcReg); } else { // Otherwise, add it to the renaming set - PHIUnion.insert(SrcReg); + LiveInterval& I = LI.getOrCreateInterval(SrcReg); + unsigned idx = LI.getMBBEndIdx(P->getOperand(i).getMBB()); + VNInfo* VN = I.getLiveRangeContaining(idx)->valno; + + assert(VN && "No VNInfo for register?"); + + PHIUnion.insert(std::make_pair(SrcReg, VN->id)); UnionedBlocks.insert(MRI.getVRegDef(SrcReg)->getParent()); } } @@ -508,7 +515,9 @@ void StrongPHIElimination::processBlock(MachineBasicBlock* MBB) { // Remember which registers are already renamed, so that we don't try to // rename them for another PHI node in this block - ProcessedNames.insert(PHIUnion.begin(), PHIUnion.end()); + for (std::map<unsigned, unsigned>::iterator I = PHIUnion.begin(), + E = PHIUnion.end(); I != E; ++I) + ProcessedNames.insert(I->first); ++P; } @@ -519,7 +528,7 @@ void StrongPHIElimination::processBlock(MachineBasicBlock* MBB) { /// that are known to interfere, and flag others that need to be checked for /// local interferences. void StrongPHIElimination::processPHIUnion(MachineInstr* Inst, - std::set<unsigned>& PHIUnion, + std::map<unsigned, unsigned>& PHIUnion, std::vector<StrongPHIElimination::DomForestNode*>& DF, std::vector<std::pair<unsigned, unsigned> >& locals) { @@ -716,6 +725,11 @@ void StrongPHIElimination::InsertCopies(MachineBasicBlock* MBB, Stacks[*I].pop_back(); } +void StrongPHIElimination::mergeLiveIntervals(unsigned primary, + unsigned secondary, unsigned VN) { + // FIXME: Update LiveIntervals +} + bool StrongPHIElimination::runOnMachineFunction(MachineFunction &Fn) { // Compute DFS numbers of each block computeDFS(Fn); @@ -732,12 +746,14 @@ bool StrongPHIElimination::runOnMachineFunction(MachineFunction &Fn) { InsertCopies(Fn.begin(), visited); // Perform renaming - typedef std::map<unsigned, std::set<unsigned> > RenameSetType; + typedef std::map<unsigned, std::map<unsigned, unsigned> > RenameSetType; for (RenameSetType::iterator I = RenameSets.begin(), E = RenameSets.end(); I != E; ++I) - for (std::set<unsigned>::iterator SI = I->second.begin(), - SE = I->second.end(); SI != SE; ++SI) - Fn.getRegInfo().replaceRegWith(*SI, I->first); + for (std::map<unsigned, unsigned>::iterator SI = I->second.begin(), + SE = I->second.end(); SI != SE; ++SI) { + mergeLiveIntervals(I->first, SI->first, SI->second); + Fn.getRegInfo().replaceRegWith(SI->first, I->first); + } // FIXME: Insert last-minute copies |