X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FPrologEpilogInserter.cpp;h=c52da321c1e9a05e922486ff70c1a21f279bc3a7;hb=3627e34486db088661bc7fb6c0dde6a18a543217;hp=9f765d43d4097c2ae87930a312522ecab009f6dd;hpb=d64b5c82b97ad1b74eb9fd2f23257a7899b0c307;p=oota-llvm.git diff --git a/lib/CodeGen/PrologEpilogInserter.cpp b/lib/CodeGen/PrologEpilogInserter.cpp index 9f765d43d40..c52da321c1e 100644 --- a/lib/CodeGen/PrologEpilogInserter.cpp +++ b/lib/CodeGen/PrologEpilogInserter.cpp @@ -2,8 +2,8 @@ // // The LLVM Compiler Infrastructure // -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // @@ -20,9 +20,11 @@ #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/RegisterScavenging.h" #include "llvm/Target/TargetMachine.h" -#include "llvm/Target/MRegisterInfo.h" +#include "llvm/Target/TargetRegisterInfo.h" #include "llvm/Target/TargetFrameInfo.h" #include "llvm/Target/TargetInstrInfo.h" #include "llvm/Support/Compiler.h" @@ -43,18 +45,17 @@ namespace { /// frame indexes with appropriate references. /// bool runOnMachineFunction(MachineFunction &Fn) { - const MRegisterInfo *MRI = Fn.getTarget().getRegisterInfo(); - RS = MRI->requiresRegisterScavenging(Fn) ? new RegScavenger() : NULL; + const TargetRegisterInfo *TRI = Fn.getTarget().getRegisterInfo(); + RS = TRI->requiresRegisterScavenging(Fn) ? new RegScavenger() : NULL; // Get MachineModuleInfo so that we can track the construction of the // frame. - if (MachineModuleInfo *MMI = getAnalysisToUpdate()) { + if (MachineModuleInfo *MMI = getAnalysisToUpdate()) Fn.getFrameInfo()->setMachineModuleInfo(MMI); - } // Allow the target machine to make some adjustments to the function // e.g. UsedPhysRegs before calculateCalleeSavedRegisters. - MRI->processFunctionBeforeCalleeSavedScan(Fn, RS); + TRI->processFunctionBeforeCalleeSavedScan(Fn, RS); // Scan the function for modified callee saved registers and insert spill // code for any callee saved registers that are modified. Also calculate @@ -67,7 +68,7 @@ namespace { // Allow the target machine to make final modifications to the function // before the frame layout is finalized. - Fn.getTarget().getRegisterInfo()->processFunctionBeforeFrameFinalized(Fn); + TRI->processFunctionBeforeFrameFinalized(Fn); // Calculate actual frame offsets for all of the abstract stack objects... calculateFrameObjectOffsets(Fn); @@ -117,7 +118,7 @@ FunctionPass *llvm::createPrologEpilogCodeInserter() { return new PEI(); } /// instructions. /// void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { - const MRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); + const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); const TargetFrameInfo *TFI = Fn.getTarget().getFrameInfo(); // Get the callee saved register list... @@ -147,7 +148,7 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { I->getOpcode() == FrameDestroyOpcode) { assert(I->getNumOperands() >= 1 && "Call Frame Setup/Destroy Pseudo" " instructions should have a single immediate argument!"); - unsigned Size = I->getOperand(0).getImmedValue(); + unsigned Size = I->getOperand(0).getImm(); if (Size > MaxCallFrameSize) MaxCallFrameSize = Size; HasCalls = true; FrameSDOps.push_back(I); @@ -174,13 +175,13 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &Fn) { std::vector CSI; for (unsigned i = 0; CSRegs[i]; ++i) { unsigned Reg = CSRegs[i]; - if (Fn.isPhysRegUsed(Reg)) { + if (Fn.getRegInfo().isPhysRegUsed(Reg)) { // If the reg is modified, save it! CSI.push_back(CalleeSavedInfo(Reg, CSRegClasses[i])); } else { for (const unsigned *AliasSet = RegInfo->getAliasSet(Reg); *AliasSet; ++AliasSet) { // Check alias registers too. - if (Fn.isPhysRegUsed(*AliasSet)) { + if (Fn.getRegInfo().isPhysRegUsed(*AliasSet)) { CSI.push_back(CalleeSavedInfo(Reg, CSRegClasses[i])); break; } @@ -241,35 +242,35 @@ void PEI::saveCalleeSavedRegisters(MachineFunction &Fn) { if (CSI.empty()) return; - const MRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); + const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo(); // Now that we have a stack slot for each register to be saved, insert spill // code into the entry block. MachineBasicBlock *MBB = Fn.begin(); MachineBasicBlock::iterator I = MBB->begin(); - if (!RegInfo->spillCalleeSavedRegisters(*MBB, I, CSI)) { + + if (!TII.spillCalleeSavedRegisters(*MBB, I, CSI)) { for (unsigned i = 0, e = CSI.size(); i != e; ++i) { // Add the callee-saved register as live-in. It's killed at the spill. MBB->addLiveIn(CSI[i].getReg()); // Insert the spill to the stack frame. - RegInfo->storeRegToStackSlot(*MBB, I, CSI[i].getReg(), true, + TII.storeRegToStackSlot(*MBB, I, CSI[i].getReg(), true, CSI[i].getFrameIdx(), CSI[i].getRegClass()); } } // Add code to restore the callee-save registers in each exiting block. - const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo(); for (MachineFunction::iterator FI = Fn.begin(), E = Fn.end(); FI != E; ++FI) // If last instruction is a return instruction, add an epilogue. - if (!FI->empty() && TII.isReturn(FI->back().getOpcode())) { + if (!FI->empty() && FI->back().getDesc().isReturn()) { MBB = FI; I = MBB->end(); --I; // Skip over all terminator instructions, which are part of the return // sequence. MachineBasicBlock::iterator I2 = I; - while (I2 != MBB->begin() && TII.isTerminatorInstr((--I2)->getOpcode())) + while (I2 != MBB->begin() && (--I2)->getDesc().isTerminator()) I = I2; bool AtStart = I == MBB->begin(); @@ -279,9 +280,9 @@ void PEI::saveCalleeSavedRegisters(MachineFunction &Fn) { // Restore all registers immediately before the return and any terminators // that preceed it. - if (!RegInfo->restoreCalleeSavedRegisters(*MBB, I, CSI)) { + if (!TII.restoreCalleeSavedRegisters(*MBB, I, CSI)) { for (unsigned i = 0, e = CSI.size(); i != e; ++i) { - RegInfo->loadRegFromStackSlot(*MBB, I, CSI[i].getReg(), + TII.loadRegFromStackSlot(*MBB, I, CSI[i].getReg(), CSI[i].getFrameIdx(), CSI[i].getRegClass()); assert(I != MBB->begin() && @@ -312,7 +313,7 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { // Loop over all of the stack objects, assigning sequential addresses... MachineFrameInfo *FFI = Fn.getFrameInfo(); - unsigned MaxAlign = 0; + unsigned MaxAlign = FFI->getMaxAlignment(); // Start at the beginning of the local area. // The Offset is the distance from the stack top in the direction @@ -361,7 +362,8 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { FFI->setObjectOffset(i, -Offset); // Set the computed offset } } else { - for (unsigned i = MaxCSFrameIndex; i >= MinCSFrameIndex; --i) { + int MaxCSFI = MaxCSFrameIndex, MinCSFI = MinCSFrameIndex; + for (int i = MaxCSFI; i >= MinCSFI ; --i) { unsigned Align = FFI->getObjectAlignment(i); // If the alignment of this object is greater than that of the stack, then // increase the stack alignment to match. @@ -376,7 +378,7 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { // Make sure the special register scavenging spill slot is closest to the // frame pointer if a frame pointer is required. - const MRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); + const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo(); if (RS && RegInfo->hasFP(Fn)) { int SFI = RS->getScavengingFrameIndex(); if (SFI >= 0) { @@ -405,6 +407,8 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { continue; if (RS && (int)i == RS->getScavengingFrameIndex()) continue; + if (FFI->isDeadObjectIndex(i)) + continue; // If stack grows down, we need to add size of find the lowest // address of the object. @@ -437,6 +441,9 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { Offset += FFI->getObjectSize(SFI); unsigned Align = FFI->getObjectAlignment(SFI); + // If the alignment of this object is greater than that of the + // stack, then increase the stack alignment to match. + MaxAlign = std::max(MaxAlign, Align); // Adjust to alignment boundary Offset = (Offset+Align-1)/Align*Align; @@ -469,8 +476,7 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { // Remember the required stack alignment in case targets need it to perform // dynamic stack alignment. - assert(FFI->getMaxAlignment() == MaxAlign && - "Stack alignment calculation broken!"); + FFI->setMaxAlignment(MaxAlign); } @@ -479,15 +485,16 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) { /// prolog and epilog code to the function. /// void PEI::insertPrologEpilogCode(MachineFunction &Fn) { + const TargetRegisterInfo *TRI = Fn.getTarget().getRegisterInfo(); + // Add prologue to the function... - Fn.getTarget().getRegisterInfo()->emitPrologue(Fn); + TRI->emitPrologue(Fn); // Add epilogue to restore the callee-save registers in each exiting block - const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo(); for (MachineFunction::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I) { // If last instruction is a return instruction, add an epilogue - if (!I->empty() && TII.isReturn(I->back().getOpcode())) - Fn.getTarget().getRegisterInfo()->emitEpilogue(Fn, *I); + if (!I->empty() && I->back().getDesc().isReturn()) + TRI->emitEpilogue(Fn, *I); } } @@ -500,12 +507,12 @@ void PEI::replaceFrameIndices(MachineFunction &Fn) { const TargetMachine &TM = Fn.getTarget(); assert(TM.getRegisterInfo() && "TM::getRegisterInfo() must be implemented!"); - const MRegisterInfo &MRI = *TM.getRegisterInfo(); + const TargetRegisterInfo &TRI = *TM.getRegisterInfo(); const TargetFrameInfo *TFI = TM.getFrameInfo(); bool StackGrowsDown = TFI->getStackGrowthDirection() == TargetFrameInfo::StackGrowsDown; - int FrameSetupOpcode = MRI.getCallFrameSetupOpcode(); - int FrameDestroyOpcode = MRI.getCallFrameDestroyOpcode(); + int FrameSetupOpcode = TRI.getCallFrameSetupOpcode(); + int FrameDestroyOpcode = TRI.getCallFrameDestroyOpcode(); for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) { int SPAdj = 0; // SP offset due to call frame setup / destroy. @@ -513,37 +520,67 @@ void PEI::replaceFrameIndices(MachineFunction &Fn) { for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ) { MachineInstr *MI = I; - // Remember how much SP has been adjustment to create the call frame. + if (I->getOpcode() == TargetInstrInfo::DECLARE) { + // Ignore it. + ++I; + continue; + } + if (I->getOpcode() == FrameSetupOpcode || I->getOpcode() == FrameDestroyOpcode) { - int Size = I->getOperand(0).getImmedValue(); + // Remember how much SP has been adjusted to create the call + // frame. + int Size = I->getOperand(0).getImm(); + if ((!StackGrowsDown && I->getOpcode() == FrameSetupOpcode) || (StackGrowsDown && I->getOpcode() == FrameDestroyOpcode)) Size = -Size; + SPAdj += Size; + MachineBasicBlock::iterator PrevI = prior(I); - MRI.eliminateCallFramePseudoInstr(Fn, *BB, I); + TRI.eliminateCallFramePseudoInstr(Fn, *BB, I); + // Visit the instructions created by eliminateCallFramePseudoInstr(). I = next(PrevI); - MI = NULL; - } else { - I++; - for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) - if (MI->getOperand(i).isFrameIndex()) { - // If this instruction has a FrameIndex operand, we need to use that - // target machine register info object to eliminate it. - MRI.eliminateFrameIndex(MI, SPAdj, RS); - - // Revisit the instruction in full. Some instructions (e.g. inline - // asm instructions) can have multiple frame indices. - --I; - MI = 0; - break; - } + continue; } + + bool DoIncr = true; + + for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) + if (MI->getOperand(i).isFrameIndex()) { + // Some instructions (e.g. inline asm instructions) can have + // multiple frame indices and/or cause eliminateFrameIndex + // to insert more than one instruction. We need the register + // scavenger to go through all of these instructions so that + // it can update its register information. We keep the + // iterator at the point before insertion so that we can + // revisit them in full. + bool AtBeginning = (I == BB->begin()); + if (!AtBeginning) --I; + + // If this instruction has a FrameIndex operand, we need to + // use that target machine register info object to eliminate + // it. + TRI.eliminateFrameIndex(MI, SPAdj, RS); + + // Reset the iterator if we were at the beginning of the BB. + if (AtBeginning) { + I = BB->begin(); + DoIncr = false; + } + + MI = 0; + break; + } + + if (DoIncr) ++I; + // Update register states. if (RS && MI) RS->forward(MI); } + assert(SPAdj == 0 && "Unbalanced call frame setup / destroy pairs?"); } }