//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "pei"
#include "PrologEpilogInserter.h"
#include "llvm/ADT/IndexedMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
#include <climits>
using namespace llvm;
+#define DEBUG_TYPE "pei"
+
char PEI::ID = 0;
char &llvm::PrologEpilogCodeInserterID = PEI::ID;
///
bool PEI::runOnMachineFunction(MachineFunction &Fn) {
const Function* F = Fn.getFunction();
- const TargetRegisterInfo *TRI = Fn.getTarget().getRegisterInfo();
- const TargetFrameLowering *TFI = Fn.getTarget().getFrameLowering();
+ const TargetRegisterInfo *TRI = Fn.getSubtarget().getRegisterInfo();
+ const TargetFrameLowering *TFI = Fn.getSubtarget().getFrameLowering();
assert(!Fn.getRegInfo().getNumVirtRegs() && "Regalloc must assign all vregs");
- RS = TRI->requiresRegisterScavenging(Fn) ? new RegScavenger() : NULL;
+ RS = TRI->requiresRegisterScavenging(Fn) ? new RegScavenger() : nullptr;
FrameIndexVirtualScavenging = TRI->requiresFrameIndexScavenging(Fn);
// Calculate the MaxCallFrameSize and AdjustsStack variables for the
replaceFrameIndices(Fn);
// If register scavenging is needed, as we've enabled doing it as a
- // post-pass, scavenge the virtual registers that frame index elimiation
+ // post-pass, scavenge the virtual registers that frame index elimination
// inserted.
if (TRI->requiresRegisterScavenging(Fn) && FrameIndexVirtualScavenging)
scavengeFrameVirtualRegs(Fn);
/// variables for the function's frame information and eliminate call frame
/// pseudo instructions.
void PEI::calculateCallsInformation(MachineFunction &Fn) {
- const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo();
- const TargetFrameLowering *TFI = Fn.getTarget().getFrameLowering();
+ const TargetInstrInfo &TII = *Fn.getSubtarget().getInstrInfo();
+ const TargetFrameLowering *TFI = Fn.getSubtarget().getFrameLowering();
MachineFrameInfo *MFI = Fn.getFrameInfo();
unsigned MaxCallFrameSize = 0;
/// calculateCalleeSavedRegisters - Scan the function for modified callee saved
/// registers.
void PEI::calculateCalleeSavedRegisters(MachineFunction &F) {
- const TargetRegisterInfo *RegInfo = F.getTarget().getRegisterInfo();
- const TargetFrameLowering *TFI = F.getTarget().getFrameLowering();
+ const TargetRegisterInfo *RegInfo = F.getSubtarget().getRegisterInfo();
+ const TargetFrameLowering *TFI = F.getSubtarget().getFrameLowering();
MachineFrameInfo *MFI = F.getFrameInfo();
// Get the callee saved register list...
- const uint16_t *CSRegs = RegInfo->getCalleeSavedRegs(&F);
+ const MCPhysReg *CSRegs = RegInfo->getCalleeSavedRegs(&F);
// These are used to keep track the callee-save area. Initialize them.
MinCSFrameIndex = INT_MAX;
MaxCSFrameIndex = 0;
// Early exit for targets which have no callee saved registers.
- if (CSRegs == 0 || CSRegs[0] == 0)
+ if (!CSRegs || CSRegs[0] == 0)
return;
// In Naked functions we aren't going to save any registers.
}
}
- if (CSI.empty())
- return; // Early exit if no callee saved registers are modified!
+ if (!TFI->assignCalleeSavedSpillSlots(F, RegInfo, CSI)) {
+ // If target doesn't implement this, use generic code.
- unsigned NumFixedSpillSlots;
- const TargetFrameLowering::SpillSlot *FixedSpillSlots =
- TFI->getCalleeSavedSpillSlots(NumFixedSpillSlots);
+ if (CSI.empty())
+ return; // Early exit if no callee saved registers are modified!
- // Now that we know which registers need to be saved and restored, allocate
- // stack slots for them.
- for (std::vector<CalleeSavedInfo>::iterator
- I = CSI.begin(), E = CSI.end(); I != E; ++I) {
- unsigned Reg = I->getReg();
- const TargetRegisterClass *RC = RegInfo->getMinimalPhysRegClass(Reg);
+ unsigned NumFixedSpillSlots;
+ const TargetFrameLowering::SpillSlot *FixedSpillSlots =
+ TFI->getCalleeSavedSpillSlots(NumFixedSpillSlots);
- int FrameIdx;
- if (RegInfo->hasReservedSpillSlot(F, Reg, FrameIdx)) {
- I->setFrameIdx(FrameIdx);
- continue;
- }
+ // Now that we know which registers need to be saved and restored, allocate
+ // stack slots for them.
+ for (std::vector<CalleeSavedInfo>::iterator I = CSI.begin(), E = CSI.end();
+ I != E; ++I) {
+ unsigned Reg = I->getReg();
+ const TargetRegisterClass *RC = RegInfo->getMinimalPhysRegClass(Reg);
- // Check to see if this physreg must be spilled to a particular stack slot
- // on this target.
- const TargetFrameLowering::SpillSlot *FixedSlot = FixedSpillSlots;
- while (FixedSlot != FixedSpillSlots+NumFixedSpillSlots &&
- FixedSlot->Reg != Reg)
- ++FixedSlot;
-
- if (FixedSlot == FixedSpillSlots + NumFixedSpillSlots) {
- // Nope, just spill it anywhere convenient.
- unsigned Align = RC->getAlignment();
- unsigned StackAlign = TFI->getStackAlignment();
-
- // We may not be able to satisfy the desired alignment specification of
- // the TargetRegisterClass if the stack alignment is smaller. Use the
- // min.
- Align = std::min(Align, StackAlign);
- FrameIdx = MFI->CreateStackObject(RC->getSize(), Align, true);
- if ((unsigned)FrameIdx < MinCSFrameIndex) MinCSFrameIndex = FrameIdx;
- if ((unsigned)FrameIdx > MaxCSFrameIndex) MaxCSFrameIndex = FrameIdx;
- } else {
- // Spill it to the stack where we must.
- FrameIdx = MFI->CreateFixedObject(RC->getSize(), FixedSlot->Offset, true);
- }
+ int FrameIdx;
+ if (RegInfo->hasReservedSpillSlot(F, Reg, FrameIdx)) {
+ I->setFrameIdx(FrameIdx);
+ continue;
+ }
- I->setFrameIdx(FrameIdx);
+ // Check to see if this physreg must be spilled to a particular stack slot
+ // on this target.
+ const TargetFrameLowering::SpillSlot *FixedSlot = FixedSpillSlots;
+ while (FixedSlot != FixedSpillSlots + NumFixedSpillSlots &&
+ FixedSlot->Reg != Reg)
+ ++FixedSlot;
+
+ if (FixedSlot == FixedSpillSlots + NumFixedSpillSlots) {
+ // Nope, just spill it anywhere convenient.
+ unsigned Align = RC->getAlignment();
+ unsigned StackAlign = TFI->getStackAlignment();
+
+ // We may not be able to satisfy the desired alignment specification of
+ // the TargetRegisterClass if the stack alignment is smaller. Use the
+ // min.
+ Align = std::min(Align, StackAlign);
+ FrameIdx = MFI->CreateStackObject(RC->getSize(), Align, true);
+ if ((unsigned)FrameIdx < MinCSFrameIndex) MinCSFrameIndex = FrameIdx;
+ if ((unsigned)FrameIdx > MaxCSFrameIndex) MaxCSFrameIndex = FrameIdx;
+ } else {
+ // Spill it to the stack where we must.
+ FrameIdx =
+ MFI->CreateFixedSpillStackObject(RC->getSize(), FixedSlot->Offset);
+ }
+
+ I->setFrameIdx(FrameIdx);
+ }
}
MFI->setCalleeSavedInfo(CSI);
if (CSI.empty())
return;
- const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo();
- const TargetFrameLowering *TFI = Fn.getTarget().getFrameLowering();
- const TargetRegisterInfo *TRI = Fn.getTarget().getRegisterInfo();
+ const TargetInstrInfo &TII = *Fn.getSubtarget().getInstrInfo();
+ const TargetFrameLowering *TFI = Fn.getSubtarget().getFrameLowering();
+ const TargetRegisterInfo *TRI = Fn.getSubtarget().getRegisterInfo();
MachineBasicBlock::iterator I;
// Spill using target interface.
/// abstract stack objects.
///
void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
- const TargetFrameLowering &TFI = *Fn.getTarget().getFrameLowering();
+ const TargetFrameLowering &TFI = *Fn.getSubtarget().getFrameLowering();
StackProtector *SP = &getAnalysis<StackProtector>();
bool StackGrowsDown =
unsigned Align = MFI->getObjectAlignment(i);
// Adjust to alignment boundary
- Offset = (Offset+Align-1)/Align*Align;
+ Offset = RoundUpToAlignment(Offset, Align);
MFI->setObjectOffset(i, -Offset); // Set the computed offset
}
for (int i = MaxCSFI; i >= MinCSFI ; --i) {
unsigned Align = MFI->getObjectAlignment(i);
// Adjust to alignment boundary
- Offset = (Offset+Align-1)/Align*Align;
+ Offset = RoundUpToAlignment(Offset, Align);
MFI->setObjectOffset(i, Offset);
Offset += MFI->getObjectSize(i);
// Make sure the special register scavenging spill slot is closest to the
// incoming stack pointer if a frame pointer is required and is closer
// to the incoming rather than the final stack pointer.
- const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
+ const TargetRegisterInfo *RegInfo = Fn.getSubtarget().getRegisterInfo();
bool EarlyScavengingSlots = (TFI.hasFP(Fn) &&
TFI.isFPCloseToIncomingSP() &&
RegInfo->useFPForScavengingIndex(Fn) &&
unsigned Align = MFI->getLocalFrameMaxAlign();
// Adjust to alignment boundary.
- Offset = (Offset + Align - 1) / Align * Align;
+ Offset = RoundUpToAlignment(Offset, Align);
DEBUG(dbgs() << "Local frame base offset: " << Offset << "\n");
// If the frame pointer is eliminated, all frame offsets will be relative to
// SP not FP. Align to MaxAlign so this works.
StackAlign = std::max(StackAlign, MaxAlign);
- unsigned AlignMask = StackAlign - 1;
- Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
+ Offset = RoundUpToAlignment(Offset, StackAlign);
}
// Update frame info to pretend that this is part of the stack...
/// prolog and epilog code to the function.
///
void PEI::insertPrologEpilogCode(MachineFunction &Fn) {
- const TargetFrameLowering &TFI = *Fn.getTarget().getFrameLowering();
+ const TargetFrameLowering &TFI = *Fn.getSubtarget().getFrameLowering();
// Add prologue to the function...
TFI.emitPrologue(Fn);
// we've been asked for it. This, when linked with a runtime with support
// for segmented stacks (libgcc is one), will result in allocating stack
// space in small chunks instead of one large contiguous block.
- if (Fn.getTarget().Options.EnableSegmentedStacks)
+ if (Fn.shouldSplitStack())
TFI.adjustForSegmentedStacks(Fn);
// Emit additional code that is required to explicitly handle the stack in
/// register references and actual offsets.
///
void PEI::replaceFrameIndices(MachineFunction &Fn) {
- if (!Fn.getFrameInfo()->hasStackObjects()) return; // Nothing to do?
+ const TargetFrameLowering &TFI = *Fn.getSubtarget().getFrameLowering();
+ if (!TFI.needsFrameIndexResolution(Fn)) return;
// Store SPAdj at exit of a basic block.
SmallVector<int, 8> SPState;
SmallPtrSet<MachineBasicBlock*, 8> Reachable;
// Iterate over the reachable blocks in DFS order.
- for (df_ext_iterator<MachineFunction*, SmallPtrSet<MachineBasicBlock*, 8> >
- DFI = df_ext_begin(&Fn, Reachable), DFE = df_ext_end(&Fn, Reachable);
+ for (auto DFI = df_ext_begin(&Fn, Reachable), DFE = df_ext_end(&Fn, Reachable);
DFI != DFE; ++DFI) {
int SPAdj = 0;
// Check the exit state of the DFS stack predecessor.
void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn,
int &SPAdj) {
- const TargetMachine &TM = Fn.getTarget();
- assert(TM.getRegisterInfo() && "TM::getRegisterInfo() must be implemented!");
- const TargetInstrInfo &TII = *Fn.getTarget().getInstrInfo();
- const TargetRegisterInfo &TRI = *TM.getRegisterInfo();
- const TargetFrameLowering *TFI = TM.getFrameLowering();
- bool StackGrowsDown =
- TFI->getStackGrowthDirection() == TargetFrameLowering::StackGrowsDown;
+ assert(Fn.getSubtarget().getRegisterInfo() &&
+ "getRegisterInfo() must be implemented!");
+ const TargetInstrInfo &TII = *Fn.getSubtarget().getInstrInfo();
+ const TargetRegisterInfo &TRI = *Fn.getSubtarget().getRegisterInfo();
+ const TargetFrameLowering *TFI = Fn.getSubtarget().getFrameLowering();
int FrameSetupOpcode = TII.getCallFrameSetupOpcode();
int FrameDestroyOpcode = TII.getCallFrameDestroyOpcode();
if (RS && !FrameIndexVirtualScavenging) RS->enterBasicBlock(BB);
+ bool InsideCallSequence = false;
+
for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ) {
if (I->getOpcode() == FrameSetupOpcode ||
I->getOpcode() == FrameDestroyOpcode) {
- // 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;
+ InsideCallSequence = (I->getOpcode() == FrameSetupOpcode);
+ SPAdj += TII.getSPAdjust(I);
MachineBasicBlock::iterator PrevI = BB->end();
- if (I != BB->begin()) PrevI = prior(I);
+ if (I != BB->begin()) PrevI = std::prev(I);
TFI->eliminateCallFramePseudoInstr(Fn, *BB, I);
// Visit the instructions created by eliminateCallFramePseudoInstr().
if (PrevI == BB->end())
I = BB->begin(); // The replaced instr was the first in the block.
else
- I = llvm::next(PrevI);
+ I = std::next(PrevI);
continue;
}
continue;
}
+ // TODO: This code should be commoned with the code for
+ // PATCHPOINT. There's no good reason for the difference in
+ // implementation other than historical accident. The only
+ // remaining difference is the unconditional use of the stack
+ // pointer as the base register.
+ if (MI->getOpcode() == TargetOpcode::STATEPOINT) {
+ assert((!MI->isDebugValue() || i == 0) &&
+ "Frame indicies can only appear as the first operand of a "
+ "DBG_VALUE machine instruction");
+ unsigned Reg;
+ MachineOperand &Offset = MI->getOperand(i + 1);
+ const unsigned refOffset =
+ TFI->getFrameIndexReferenceFromSP(Fn, MI->getOperand(i).getIndex(),
+ Reg);
+
+ Offset.setImm(Offset.getImm() + refOffset);
+ MI->getOperand(i).ChangeToRegister(Reg, false /*isDef*/);
+ continue;
+ }
+
+ // Frame allocations are target independent. Simply swap the index with
+ // the offset.
+ if (MI->getOpcode() == TargetOpcode::FRAME_ALLOC) {
+ assert(TFI->hasFP(Fn) && "frame alloc requires FP");
+ MachineOperand &FI = MI->getOperand(i);
+ unsigned Reg;
+ int FrameOffset = TFI->getFrameIndexReference(Fn, FI.getIndex(), Reg);
+ FI.ChangeToImmediate(FrameOffset);
+ continue;
+ }
+
// 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
// use that target machine register info object to eliminate
// it.
TRI.eliminateFrameIndex(MI, SPAdj, i,
- FrameIndexVirtualScavenging ? NULL : RS);
+ FrameIndexVirtualScavenging ? nullptr : RS);
// Reset the iterator if we were at the beginning of the BB.
if (AtBeginning) {
DoIncr = false;
}
- MI = 0;
+ MI = nullptr;
break;
}
+ // If we are looking at a call sequence, we need to keep track of
+ // the SP adjustment made by each instruction in the sequence.
+ // This includes both the frame setup/destroy pseudos (handled above),
+ // as well as other instructions that have side effects w.r.t the SP.
+ // Note that this must come after eliminateFrameIndex, because
+ // if I itself referred to a frame index, we shouldn't count its own
+ // adjustment.
+ if (MI && InsideCallSequence)
+ SPAdj += TII.getSPAdjust(MI);
+
if (DoIncr && I != BB->end()) ++I;
// Update register states.
/// FIXME: Iterating over the instruction stream is unnecessary. We can simply
/// iterate over the vreg use list, which at this point only contains machine
/// operands for which eliminateFrameIndex need a new scratch reg.
-void PEI::scavengeFrameVirtualRegs(MachineFunction &Fn) {
+void
+PEI::scavengeFrameVirtualRegs(MachineFunction &Fn) {
// Run through the instructions and find any virtual registers.
for (MachineFunction::iterator BB = Fn.begin(),
E = Fn.end(); BB != E; ++BB) {
// We might end up here again with a NULL iterator if we scavenged a
// register for which we inserted spill code for definition by what was
// originally the first instruction in BB.
- if (I == MachineBasicBlock::iterator(NULL))
+ if (I == MachineBasicBlock::iterator(nullptr))
I = BB->begin();
MachineInstr *MI = I;
- MachineBasicBlock::iterator J = llvm::next(I);
- MachineBasicBlock::iterator P = I == BB->begin() ?
- MachineBasicBlock::iterator(NULL) : llvm::prior(I);
+ MachineBasicBlock::iterator J = std::next(I);
+ MachineBasicBlock::iterator P =
+ I == BB->begin() ? MachineBasicBlock::iterator(nullptr)
+ : std::prev(I);
// RS should process this instruction before we might scavenge at this
// location. This is because we might be replacing a virtual register
// Replace this reference to the virtual register with the
// scratch register.
assert (ScratchReg && "Missing scratch register!");
+ MachineRegisterInfo &MRI = Fn.getRegInfo();
Fn.getRegInfo().replaceRegWith(Reg, ScratchReg);
+
+ // Make sure MRI now accounts this register as used.
+ MRI.setPhysRegUsed(ScratchReg);
// Because this instruction was processed by the RS before this
// register was allocated, make sure that the RS now records the
// register as being used.
- RS->setUsed(ScratchReg);
+ RS->setRegUsed(ScratchReg);
}
}
// spill code will have been inserted in between I and J. This is a
// problem because we need the spill code before I: Move I to just
// prior to J.
- if (I != llvm::prior(J)) {
+ if (I != std::prev(J)) {
BB->splice(J, BB, I);
// Before we move I, we need to prepare the RS to visit I again.
projects / oota-llvm.git / blobdiff