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Diffstat (limited to 'lib/Target/SystemZ/SystemZFrameLowering.cpp')
| -rw-r--r-- | lib/Target/SystemZ/SystemZFrameLowering.cpp | 386 |
1 files changed, 0 insertions, 386 deletions
diff --git a/lib/Target/SystemZ/SystemZFrameLowering.cpp b/lib/Target/SystemZ/SystemZFrameLowering.cpp deleted file mode 100644 index 2ad84a2d05..0000000000 --- a/lib/Target/SystemZ/SystemZFrameLowering.cpp +++ /dev/null @@ -1,386 +0,0 @@ -//=====- SystemZFrameLowering.cpp - SystemZ Frame Information ------*- C++ -*-====// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file contains the SystemZ implementation of TargetFrameLowering class. -// -//===----------------------------------------------------------------------===// - -#include "SystemZFrameLowering.h" -#include "SystemZInstrBuilder.h" -#include "SystemZInstrInfo.h" -#include "SystemZMachineFunctionInfo.h" -#include "llvm/Function.h" -#include "llvm/CodeGen/MachineFrameInfo.h" -#include "llvm/CodeGen/MachineFunction.h" -#include "llvm/CodeGen/MachineInstrBuilder.h" -#include "llvm/CodeGen/MachineModuleInfo.h" -#include "llvm/CodeGen/MachineRegisterInfo.h" -#include "llvm/Target/TargetData.h" -#include "llvm/Target/TargetOptions.h" -#include "llvm/Support/CommandLine.h" - -using namespace llvm; - -SystemZFrameLowering::SystemZFrameLowering(const SystemZSubtarget &sti) - : TargetFrameLowering(TargetFrameLowering::StackGrowsDown, 8, -160), STI(sti) { - // Fill the spill offsets map - static const unsigned SpillOffsTab[][2] = { - { SystemZ::R2D, 0x10 }, - { SystemZ::R3D, 0x18 }, - { SystemZ::R4D, 0x20 }, - { SystemZ::R5D, 0x28 }, - { SystemZ::R6D, 0x30 }, - { SystemZ::R7D, 0x38 }, - { SystemZ::R8D, 0x40 }, - { SystemZ::R9D, 0x48 }, - { SystemZ::R10D, 0x50 }, - { SystemZ::R11D, 0x58 }, - { SystemZ::R12D, 0x60 }, - { SystemZ::R13D, 0x68 }, - { SystemZ::R14D, 0x70 }, - { SystemZ::R15D, 0x78 } - }; - - RegSpillOffsets.grow(SystemZ::NUM_TARGET_REGS); - - for (unsigned i = 0, e = array_lengthof(SpillOffsTab); i != e; ++i) - RegSpillOffsets[SpillOffsTab[i][0]] = SpillOffsTab[i][1]; -} - -/// needsFP - Return true if the specified function should have a dedicated -/// frame pointer register. This is true if the function has variable sized -/// allocas or if frame pointer elimination is disabled. -bool SystemZFrameLowering::hasFP(const MachineFunction &MF) const { - const MachineFrameInfo *MFI = MF.getFrameInfo(); - return DisableFramePointerElim(MF) || MFI->hasVarSizedObjects(); -} - -/// emitSPUpdate - Emit a series of instructions to increment / decrement the -/// stack pointer by a constant value. -static -void emitSPUpdate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, - int64_t NumBytes, const TargetInstrInfo &TII) { - unsigned Opc; uint64_t Chunk; - bool isSub = NumBytes < 0; - uint64_t Offset = isSub ? -NumBytes : NumBytes; - - if (Offset >= (1LL << 15) - 1) { - Opc = SystemZ::ADD64ri32; - Chunk = (1LL << 31) - 1; - } else { - Opc = SystemZ::ADD64ri16; - Chunk = (1LL << 15) - 1; - } - - DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc(); - - while (Offset) { - uint64_t ThisVal = (Offset > Chunk) ? Chunk : Offset; - MachineInstr *MI = - BuildMI(MBB, MBBI, DL, TII.get(Opc), SystemZ::R15D) - .addReg(SystemZ::R15D).addImm(isSub ? -ThisVal : ThisVal); - // The PSW implicit def is dead. - MI->getOperand(3).setIsDead(); - Offset -= ThisVal; - } -} - -void SystemZFrameLowering::emitPrologue(MachineFunction &MF) const { - MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB - MachineFrameInfo *MFI = MF.getFrameInfo(); - const SystemZInstrInfo &TII = - *static_cast<const SystemZInstrInfo*>(MF.getTarget().getInstrInfo()); - SystemZMachineFunctionInfo *SystemZMFI = - MF.getInfo<SystemZMachineFunctionInfo>(); - MachineBasicBlock::iterator MBBI = MBB.begin(); - DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc(); - - // Get the number of bytes to allocate from the FrameInfo. - // Note that area for callee-saved stuff is already allocated, thus we need to - // 'undo' the stack movement. - uint64_t StackSize = MFI->getStackSize(); - StackSize -= SystemZMFI->getCalleeSavedFrameSize(); - - uint64_t NumBytes = StackSize - getOffsetOfLocalArea(); - - // Skip the callee-saved push instructions. - while (MBBI != MBB.end() && - (MBBI->getOpcode() == SystemZ::MOV64mr || - MBBI->getOpcode() == SystemZ::MOV64mrm)) - ++MBBI; - - if (MBBI != MBB.end()) - DL = MBBI->getDebugLoc(); - - // adjust stack pointer: R15 -= numbytes - if (StackSize || MFI->hasCalls()) { - assert(MF.getRegInfo().isPhysRegUsed(SystemZ::R15D) && - "Invalid stack frame calculation!"); - emitSPUpdate(MBB, MBBI, -(int64_t)NumBytes, TII); - } - - if (hasFP(MF)) { - // Update R11 with the new base value... - BuildMI(MBB, MBBI, DL, TII.get(SystemZ::MOV64rr), SystemZ::R11D) - .addReg(SystemZ::R15D); - - // Mark the FramePtr as live-in in every block except the entry. - for (MachineFunction::iterator I = llvm::next(MF.begin()), E = MF.end(); - I != E; ++I) - I->addLiveIn(SystemZ::R11D); - - } -} - -void SystemZFrameLowering::emitEpilogue(MachineFunction &MF, - MachineBasicBlock &MBB) const { - const MachineFrameInfo *MFI = MF.getFrameInfo(); - MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr(); - const SystemZInstrInfo &TII = - *static_cast<const SystemZInstrInfo*>(MF.getTarget().getInstrInfo()); - SystemZMachineFunctionInfo *SystemZMFI = - MF.getInfo<SystemZMachineFunctionInfo>(); - unsigned RetOpcode = MBBI->getOpcode(); - - switch (RetOpcode) { - case SystemZ::RET: break; // These are ok - default: - assert(0 && "Can only insert epilog into returning blocks"); - } - - // Get the number of bytes to allocate from the FrameInfo - // Note that area for callee-saved stuff is already allocated, thus we need to - // 'undo' the stack movement. - uint64_t StackSize = - MFI->getStackSize() - SystemZMFI->getCalleeSavedFrameSize(); - uint64_t NumBytes = StackSize - getOffsetOfLocalArea(); - - // Skip the final terminator instruction. - while (MBBI != MBB.begin()) { - MachineBasicBlock::iterator PI = prior(MBBI); - --MBBI; - if (!PI->getDesc().isTerminator()) - break; - } - - // During callee-saved restores emission stack frame was not yet finialized - // (and thus - the stack size was unknown). Tune the offset having full stack - // size in hands. - if (StackSize || MFI->hasCalls()) { - assert((MBBI->getOpcode() == SystemZ::MOV64rmm || - MBBI->getOpcode() == SystemZ::MOV64rm) && - "Expected to see callee-save register restore code"); - assert(MF.getRegInfo().isPhysRegUsed(SystemZ::R15D) && - "Invalid stack frame calculation!"); - - unsigned i = 0; - MachineInstr &MI = *MBBI; - while (!MI.getOperand(i).isImm()) { - ++i; - assert(i < MI.getNumOperands() && "Unexpected restore code!"); - } - - uint64_t Offset = NumBytes + MI.getOperand(i).getImm(); - // If Offset does not fit into 20-bit signed displacement field we need to - // emit some additional code... - if (Offset > 524287) { - // Fold the displacement into load instruction as much as possible. - NumBytes = Offset - 524287; - Offset = 524287; - emitSPUpdate(MBB, MBBI, NumBytes, TII); - } - - MI.getOperand(i).ChangeToImmediate(Offset); - } -} - -int SystemZFrameLowering::getFrameIndexOffset(const MachineFunction &MF, - int FI) const { - const MachineFrameInfo *MFI = MF.getFrameInfo(); - const SystemZMachineFunctionInfo *SystemZMFI = - MF.getInfo<SystemZMachineFunctionInfo>(); - int Offset = MFI->getObjectOffset(FI) + MFI->getOffsetAdjustment(); - uint64_t StackSize = MFI->getStackSize(); - - // Fixed objects are really located in the "previous" frame. - if (FI < 0) - StackSize -= SystemZMFI->getCalleeSavedFrameSize(); - - Offset += StackSize - getOffsetOfLocalArea(); - - // Skip the register save area if we generated the stack frame. - if (StackSize || MFI->hasCalls()) - Offset -= getOffsetOfLocalArea(); - - return Offset; -} - -bool -SystemZFrameLowering::spillCalleeSavedRegisters(MachineBasicBlock &MBB, - MachineBasicBlock::iterator MI, - const std::vector<CalleeSavedInfo> &CSI, - const TargetRegisterInfo *TRI) const { - if (CSI.empty()) - return false; - - DebugLoc DL; - if (MI != MBB.end()) DL = MI->getDebugLoc(); - - MachineFunction &MF = *MBB.getParent(); - const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo(); - SystemZMachineFunctionInfo *MFI = MF.getInfo<SystemZMachineFunctionInfo>(); - unsigned CalleeFrameSize = 0; - - // Scan the callee-saved and find the bounds of register spill area. - unsigned LowReg = 0, HighReg = 0, StartOffset = -1U, EndOffset = 0; - for (unsigned i = 0, e = CSI.size(); i != e; ++i) { - unsigned Reg = CSI[i].getReg(); - if (!SystemZ::FP64RegClass.contains(Reg)) { - unsigned Offset = RegSpillOffsets[Reg]; - CalleeFrameSize += 8; - if (StartOffset > Offset) { - LowReg = Reg; StartOffset = Offset; - } - if (EndOffset < Offset) { - HighReg = Reg; EndOffset = RegSpillOffsets[Reg]; - } - } - } - - // Save information for epilogue inserter. - MFI->setCalleeSavedFrameSize(CalleeFrameSize); - MFI->setLowReg(LowReg); MFI->setHighReg(HighReg); - - // Save GPRs - if (StartOffset) { - // Build a store instruction. Use STORE MULTIPLE instruction if there are many - // registers to store, otherwise - just STORE. - MachineInstrBuilder MIB = - BuildMI(MBB, MI, DL, TII.get((LowReg == HighReg ? - SystemZ::MOV64mr : SystemZ::MOV64mrm))); - - // Add store operands. - MIB.addReg(SystemZ::R15D).addImm(StartOffset); - if (LowReg == HighReg) - MIB.addReg(0); - MIB.addReg(LowReg, RegState::Kill); - if (LowReg != HighReg) - MIB.addReg(HighReg, RegState::Kill); - - // Do a second scan adding regs as being killed by instruction - for (unsigned i = 0, e = CSI.size(); i != e; ++i) { - unsigned Reg = CSI[i].getReg(); - // Add the callee-saved register as live-in. It's killed at the spill. - MBB.addLiveIn(Reg); - if (Reg != LowReg && Reg != HighReg) - MIB.addReg(Reg, RegState::ImplicitKill); - } - } - - // Save FPRs - for (unsigned i = 0, e = CSI.size(); i != e; ++i) { - unsigned Reg = CSI[i].getReg(); - if (SystemZ::FP64RegClass.contains(Reg)) { - MBB.addLiveIn(Reg); - TII.storeRegToStackSlot(MBB, MI, Reg, true, CSI[i].getFrameIdx(), - &SystemZ::FP64RegClass, TRI); - } - } - - return true; -} - -bool -SystemZFrameLowering::restoreCalleeSavedRegisters(MachineBasicBlock &MBB, - MachineBasicBlock::iterator MI, - const std::vector<CalleeSavedInfo> &CSI, - const TargetRegisterInfo *TRI) const { - if (CSI.empty()) - return false; - - DebugLoc DL; - if (MI != MBB.end()) DL = MI->getDebugLoc(); - - MachineFunction &MF = *MBB.getParent(); - const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo(); - SystemZMachineFunctionInfo *MFI = MF.getInfo<SystemZMachineFunctionInfo>(); - - // Restore FP registers - for (unsigned i = 0, e = CSI.size(); i != e; ++i) { - unsigned Reg = CSI[i].getReg(); - if (SystemZ::FP64RegClass.contains(Reg)) - TII.loadRegFromStackSlot(MBB, MI, Reg, CSI[i].getFrameIdx(), - &SystemZ::FP64RegClass, TRI); - } - - // Restore GP registers - unsigned LowReg = MFI->getLowReg(), HighReg = MFI->getHighReg(); - unsigned StartOffset = RegSpillOffsets[LowReg]; - - if (StartOffset) { - // Build a load instruction. Use LOAD MULTIPLE instruction if there are many - // registers to load, otherwise - just LOAD. - MachineInstrBuilder MIB = - BuildMI(MBB, MI, DL, TII.get((LowReg == HighReg ? - SystemZ::MOV64rm : SystemZ::MOV64rmm))); - // Add store operands. - MIB.addReg(LowReg, RegState::Define); - if (LowReg != HighReg) - MIB.addReg(HighReg, RegState::Define); - - MIB.addReg(hasFP(MF) ? SystemZ::R11D : SystemZ::R15D); - MIB.addImm(StartOffset); - if (LowReg == HighReg) - MIB.addReg(0); - - // Do a second scan adding regs as being defined by instruction - for (unsigned i = 0, e = CSI.size(); i != e; ++i) { - unsigned Reg = CSI[i].getReg(); - if (Reg != LowReg && Reg != HighReg) - MIB.addReg(Reg, RegState::ImplicitDefine); - } - } - - return true; -} - -void -SystemZFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF, - RegScavenger *RS) const { - // Determine whether R15/R14 will ever be clobbered inside the function. And - // if yes - mark it as 'callee' saved. - MachineFrameInfo *FFI = MF.getFrameInfo(); - MachineRegisterInfo &MRI = MF.getRegInfo(); - - // Check whether high FPRs are ever used, if yes - we need to save R15 as - // well. - static const unsigned HighFPRs[] = { - SystemZ::F8L, SystemZ::F9L, SystemZ::F10L, SystemZ::F11L, - SystemZ::F12L, SystemZ::F13L, SystemZ::F14L, SystemZ::F15L, - SystemZ::F8S, SystemZ::F9S, SystemZ::F10S, SystemZ::F11S, - SystemZ::F12S, SystemZ::F13S, SystemZ::F14S, SystemZ::F15S, - }; - - bool HighFPRsUsed = false; - for (unsigned i = 0, e = array_lengthof(HighFPRs); i != e; ++i) - HighFPRsUsed |= MRI.isPhysRegUsed(HighFPRs[i]); - - if (FFI->hasCalls()) - /* FIXME: function is varargs */ - /* FIXME: function grabs RA */ - /* FIXME: function calls eh_return */ - MRI.setPhysRegUsed(SystemZ::R14D); - - if (HighFPRsUsed || - FFI->hasCalls() || - FFI->getObjectIndexEnd() != 0 || // Contains automatic variables - FFI->hasVarSizedObjects() // Function calls dynamic alloca's - /* FIXME: function is varargs */) - MRI.setPhysRegUsed(SystemZ::R15D); -} |