llvm-6502/lib/Target/MSP430/MSP430FrameLowering.cpp
Chandler Carruth d04a8d4b33 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169131 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-03 16:50:05 +00:00

238 lines
8.2 KiB
C++

//===-- MSP430FrameLowering.cpp - MSP430 Frame Information ----------------===//
//
// 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 MSP430 implementation of TargetFrameLowering class.
//
//===----------------------------------------------------------------------===//
#include "MSP430FrameLowering.h"
#include "MSP430InstrInfo.h"
#include "MSP430MachineFunctionInfo.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/DataLayout.h"
#include "llvm/Function.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
bool MSP430FrameLowering::hasFP(const MachineFunction &MF) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
return (MF.getTarget().Options.DisableFramePointerElim(MF) ||
MF.getFrameInfo()->hasVarSizedObjects() ||
MFI->isFrameAddressTaken());
}
bool MSP430FrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
return !MF.getFrameInfo()->hasVarSizedObjects();
}
void MSP430FrameLowering::emitPrologue(MachineFunction &MF) const {
MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
MachineFrameInfo *MFI = MF.getFrameInfo();
MSP430MachineFunctionInfo *MSP430FI = MF.getInfo<MSP430MachineFunctionInfo>();
const MSP430InstrInfo &TII =
*static_cast<const MSP430InstrInfo*>(MF.getTarget().getInstrInfo());
MachineBasicBlock::iterator MBBI = MBB.begin();
DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
// Get the number of bytes to allocate from the FrameInfo.
uint64_t StackSize = MFI->getStackSize();
uint64_t NumBytes = 0;
if (hasFP(MF)) {
// Calculate required stack adjustment
uint64_t FrameSize = StackSize - 2;
NumBytes = FrameSize - MSP430FI->getCalleeSavedFrameSize();
// Get the offset of the stack slot for the EBP register... which is
// guaranteed to be the last slot by processFunctionBeforeFrameFinalized.
// Update the frame offset adjustment.
MFI->setOffsetAdjustment(-NumBytes);
// Save FPW into the appropriate stack slot...
BuildMI(MBB, MBBI, DL, TII.get(MSP430::PUSH16r))
.addReg(MSP430::FPW, RegState::Kill);
// Update FPW with the new base value...
BuildMI(MBB, MBBI, DL, TII.get(MSP430::MOV16rr), MSP430::FPW)
.addReg(MSP430::SPW);
// 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(MSP430::FPW);
} else
NumBytes = StackSize - MSP430FI->getCalleeSavedFrameSize();
// Skip the callee-saved push instructions.
while (MBBI != MBB.end() && (MBBI->getOpcode() == MSP430::PUSH16r))
++MBBI;
if (MBBI != MBB.end())
DL = MBBI->getDebugLoc();
if (NumBytes) { // adjust stack pointer: SPW -= numbytes
// If there is an SUB16ri of SPW immediately before this instruction, merge
// the two.
//NumBytes -= mergeSPUpdates(MBB, MBBI, true);
// If there is an ADD16ri or SUB16ri of SPW immediately after this
// instruction, merge the two instructions.
// mergeSPUpdatesDown(MBB, MBBI, &NumBytes);
if (NumBytes) {
MachineInstr *MI =
BuildMI(MBB, MBBI, DL, TII.get(MSP430::SUB16ri), MSP430::SPW)
.addReg(MSP430::SPW).addImm(NumBytes);
// The SRW implicit def is dead.
MI->getOperand(3).setIsDead();
}
}
}
void MSP430FrameLowering::emitEpilogue(MachineFunction &MF,
MachineBasicBlock &MBB) const {
const MachineFrameInfo *MFI = MF.getFrameInfo();
MSP430MachineFunctionInfo *MSP430FI = MF.getInfo<MSP430MachineFunctionInfo>();
const MSP430InstrInfo &TII =
*static_cast<const MSP430InstrInfo*>(MF.getTarget().getInstrInfo());
MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
unsigned RetOpcode = MBBI->getOpcode();
DebugLoc DL = MBBI->getDebugLoc();
switch (RetOpcode) {
case MSP430::RET:
case MSP430::RETI: break; // These are ok
default:
llvm_unreachable("Can only insert epilog into returning blocks");
}
// Get the number of bytes to allocate from the FrameInfo
uint64_t StackSize = MFI->getStackSize();
unsigned CSSize = MSP430FI->getCalleeSavedFrameSize();
uint64_t NumBytes = 0;
if (hasFP(MF)) {
// Calculate required stack adjustment
uint64_t FrameSize = StackSize - 2;
NumBytes = FrameSize - CSSize;
// pop FPW.
BuildMI(MBB, MBBI, DL, TII.get(MSP430::POP16r), MSP430::FPW);
} else
NumBytes = StackSize - CSSize;
// Skip the callee-saved pop instructions.
while (MBBI != MBB.begin()) {
MachineBasicBlock::iterator PI = prior(MBBI);
unsigned Opc = PI->getOpcode();
if (Opc != MSP430::POP16r && !PI->isTerminator())
break;
--MBBI;
}
DL = MBBI->getDebugLoc();
// If there is an ADD16ri or SUB16ri of SPW immediately before this
// instruction, merge the two instructions.
//if (NumBytes || MFI->hasVarSizedObjects())
// mergeSPUpdatesUp(MBB, MBBI, StackPtr, &NumBytes);
if (MFI->hasVarSizedObjects()) {
BuildMI(MBB, MBBI, DL,
TII.get(MSP430::MOV16rr), MSP430::SPW).addReg(MSP430::FPW);
if (CSSize) {
MachineInstr *MI =
BuildMI(MBB, MBBI, DL,
TII.get(MSP430::SUB16ri), MSP430::SPW)
.addReg(MSP430::SPW).addImm(CSSize);
// The SRW implicit def is dead.
MI->getOperand(3).setIsDead();
}
} else {
// adjust stack pointer back: SPW += numbytes
if (NumBytes) {
MachineInstr *MI =
BuildMI(MBB, MBBI, DL, TII.get(MSP430::ADD16ri), MSP430::SPW)
.addReg(MSP430::SPW).addImm(NumBytes);
// The SRW implicit def is dead.
MI->getOperand(3).setIsDead();
}
}
}
// FIXME: Can we eleminate these in favour of generic code?
bool
MSP430FrameLowering::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();
MSP430MachineFunctionInfo *MFI = MF.getInfo<MSP430MachineFunctionInfo>();
MFI->setCalleeSavedFrameSize(CSI.size() * 2);
for (unsigned i = CSI.size(); i != 0; --i) {
unsigned Reg = CSI[i-1].getReg();
// Add the callee-saved register as live-in. It's killed at the spill.
MBB.addLiveIn(Reg);
BuildMI(MBB, MI, DL, TII.get(MSP430::PUSH16r))
.addReg(Reg, RegState::Kill);
}
return true;
}
bool
MSP430FrameLowering::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();
for (unsigned i = 0, e = CSI.size(); i != e; ++i)
BuildMI(MBB, MI, DL, TII.get(MSP430::POP16r), CSI[i].getReg());
return true;
}
void
MSP430FrameLowering::processFunctionBeforeFrameFinalized(MachineFunction &MF)
const {
const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
// Create a frame entry for the FPW register that must be saved.
if (TFI->hasFP(MF)) {
int FrameIdx = MF.getFrameInfo()->CreateFixedObject(2, -4, true);
(void)FrameIdx;
assert(FrameIdx == MF.getFrameInfo()->getObjectIndexBegin() &&
"Slot for FPW register must be last in order to be found!");
}
}