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-rw-r--r--gnu/llvm/lib/CodeGen/PrologEpilogInserter.cpp172
1 files changed, 42 insertions, 130 deletions
diff --git a/gnu/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/gnu/llvm/lib/CodeGen/PrologEpilogInserter.cpp
index 5fca7fa5536..e9f8d43fe64 100644
--- a/gnu/llvm/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/gnu/llvm/lib/CodeGen/PrologEpilogInserter.cpp
@@ -45,7 +45,7 @@
using namespace llvm;
-#define DEBUG_TYPE "pei"
+#define DEBUG_TYPE "prologepilog"
typedef SmallVector<MachineBasicBlock *, 4> MBBVector;
static void doSpillCalleeSavedRegs(MachineFunction &MF, RegScavenger *RS,
@@ -54,25 +54,12 @@ static void doSpillCalleeSavedRegs(MachineFunction &MF, RegScavenger *RS,
const MBBVector &SaveBlocks,
const MBBVector &RestoreBlocks);
-static void doScavengeFrameVirtualRegs(MachineFunction &MF, RegScavenger *RS);
-
namespace {
class PEI : public MachineFunctionPass {
public:
static char ID;
- explicit PEI(const TargetMachine *TM = nullptr) : MachineFunctionPass(ID) {
+ PEI() : MachineFunctionPass(ID) {
initializePEIPass(*PassRegistry::getPassRegistry());
-
- if (TM && (!TM->usesPhysRegsForPEI())) {
- SpillCalleeSavedRegisters = [](MachineFunction &, RegScavenger *,
- unsigned &, unsigned &, const MBBVector &,
- const MBBVector &) {};
- ScavengeFrameVirtualRegs = [](MachineFunction &, RegScavenger *) {};
- } else {
- SpillCalleeSavedRegisters = doSpillCalleeSavedRegs;
- ScavengeFrameVirtualRegs = doScavengeFrameVirtualRegs;
- UsesCalleeSaves = true;
- }
}
void getAnalysisUsage(AnalysisUsage &AU) const override;
@@ -95,7 +82,7 @@ private:
const MBBVector &SaveBlocks,
const MBBVector &RestoreBlocks)>
SpillCalleeSavedRegisters;
- std::function<void(MachineFunction &MF, RegScavenger *RS)>
+ std::function<void(MachineFunction &MF, RegScavenger &RS)>
ScavengeFrameVirtualRegs;
bool UsesCalleeSaves = false;
@@ -140,21 +127,19 @@ WarnStackSize("warn-stack-size", cl::Hidden, cl::init((unsigned)-1),
cl::desc("Warn for stack size bigger than the given"
" number"));
-INITIALIZE_TM_PASS_BEGIN(PEI, "prologepilog", "Prologue/Epilogue Insertion",
- false, false)
+INITIALIZE_PASS_BEGIN(PEI, DEBUG_TYPE, "Prologue/Epilogue Insertion", false,
+ false)
INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
INITIALIZE_PASS_DEPENDENCY(StackProtector)
-INITIALIZE_TM_PASS_END(PEI, "prologepilog",
- "Prologue/Epilogue Insertion & Frame Finalization",
- false, false)
+INITIALIZE_PASS_END(PEI, DEBUG_TYPE,
+ "Prologue/Epilogue Insertion & Frame Finalization", false,
+ false)
-MachineFunctionPass *
-llvm::createPrologEpilogInserterPass(const TargetMachine *TM) {
- return new PEI(TM);
+MachineFunctionPass *llvm::createPrologEpilogInserterPass() {
+ return new PEI();
}
-STATISTIC(NumScavengedRegs, "Number of frame index regs scavenged");
STATISTIC(NumBytesStackSpace,
"Number of bytes used for stack in all functions");
@@ -174,6 +159,20 @@ typedef SmallSetVector<int, 8> StackObjSet;
/// frame indexes with appropriate references.
///
bool PEI::runOnMachineFunction(MachineFunction &Fn) {
+ if (!SpillCalleeSavedRegisters) {
+ const TargetMachine &TM = Fn.getTarget();
+ if (!TM.usesPhysRegsForPEI()) {
+ SpillCalleeSavedRegisters = [](MachineFunction &, RegScavenger *,
+ unsigned &, unsigned &, const MBBVector &,
+ const MBBVector &) {};
+ ScavengeFrameVirtualRegs = [](MachineFunction &, RegScavenger &) {};
+ } else {
+ SpillCalleeSavedRegisters = doSpillCalleeSavedRegs;
+ ScavengeFrameVirtualRegs = scavengeFrameVirtualRegs;
+ UsesCalleeSaves = true;
+ }
+ }
+
const Function* F = Fn.getFunction();
const TargetRegisterInfo *TRI = Fn.getSubtarget().getRegisterInfo();
const TargetFrameLowering *TFI = Fn.getSubtarget().getFrameLowering();
@@ -220,7 +219,7 @@ bool PEI::runOnMachineFunction(MachineFunction &Fn) {
// post-pass, scavenge the virtual registers that frame index elimination
// inserted.
if (TRI->requiresRegisterScavenging(Fn) && FrameIndexVirtualScavenging) {
- ScavengeFrameVirtualRegs(Fn, RS);
+ ScavengeFrameVirtualRegs(Fn, *RS);
// Clear any vregs created by virtual scavenging.
Fn.getRegInfo().clearVirtRegs();
@@ -265,11 +264,8 @@ void PEI::calculateCallFrameInfo(MachineFunction &Fn) {
std::vector<MachineBasicBlock::iterator> FrameSDOps;
for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB)
for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ++I)
- if (I->getOpcode() == FrameSetupOpcode ||
- I->getOpcode() == FrameDestroyOpcode) {
- assert(I->getNumOperands() >= 1 && "Call Frame Setup/Destroy Pseudo"
- " instructions should have a single immediate argument!");
- unsigned Size = I->getOperand(0).getImm();
+ if (TII.isFrameInstr(*I)) {
+ unsigned Size = TII.getFrameSize(*I);
if (Size > MaxCallFrameSize) MaxCallFrameSize = Size;
AdjustsStack = true;
FrameSDOps.push_back(I);
@@ -280,6 +276,9 @@ void PEI::calculateCallFrameInfo(MachineFunction &Fn) {
AdjustsStack = true;
}
+ assert(!MFI.isMaxCallFrameSizeComputed() ||
+ (MFI.getMaxCallFrameSize() == MaxCallFrameSize &&
+ MFI.adjustsStack() == AdjustsStack));
MFI.setAdjustsStack(AdjustsStack);
MFI.setMaxCallFrameSize(MaxCallFrameSize);
@@ -336,7 +335,7 @@ static void assignCalleeSavedSpillSlots(MachineFunction &F,
return;
const TargetRegisterInfo *RegInfo = F.getSubtarget().getRegisterInfo();
- const MCPhysReg *CSRegs = RegInfo->getCalleeSavedRegs(&F);
+ const MCPhysReg *CSRegs = F.getRegInfo().getCalleeSavedRegs();
std::vector<CalleeSavedInfo> CSI;
for (unsigned i = 0; CSRegs[i]; ++i) {
@@ -376,22 +375,22 @@ static void assignCalleeSavedSpillSlots(MachineFunction &F,
FixedSlot->Reg != Reg)
++FixedSlot;
+ unsigned Size = RegInfo->getSpillSize(*RC);
if (FixedSlot == FixedSpillSlots + NumFixedSpillSlots) {
// Nope, just spill it anywhere convenient.
- unsigned Align = RC->getAlignment();
+ unsigned Align = RegInfo->getSpillAlignment(*RC);
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);
+ FrameIdx = MFI.CreateStackObject(Size, 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);
+ FrameIdx = MFI.CreateFixedSpillStackObject(Size, FixedSlot->Offset);
}
CS.setFrameIdx(FrameIdx);
@@ -448,12 +447,13 @@ static void updateLiveness(MachineFunction &MF) {
const std::vector<CalleeSavedInfo> &CSI = MFI.getCalleeSavedInfo();
+ MachineRegisterInfo &MRI = MF.getRegInfo();
for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
for (MachineBasicBlock *MBB : Visited) {
MCPhysReg Reg = CSI[i].getReg();
// Add the callee-saved register as live-in.
// It's killed at the spill.
- if (!MBB->isLiveIn(Reg))
+ if (!MRI.isReserved(Reg) && !MBB->isLiveIn(Reg))
MBB->addLiveIn(Reg);
}
}
@@ -764,6 +764,9 @@ void PEI::calculateFrameObjectOffsets(MachineFunction &Fn) {
} else if (MaxCSFrameIndex >= MinCSFrameIndex) {
// Be careful about underflow in comparisons agains MinCSFrameIndex.
for (unsigned i = MaxCSFrameIndex; i != MinCSFrameIndex - 1; --i) {
+ if (MFI.isDeadObjectIndex(i))
+ continue;
+
unsigned Align = MFI.getObjectAlignment(i);
// Adjust to alignment boundary
Offset = alignTo(Offset, Align, Skew);
@@ -1049,8 +1052,6 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn,
const TargetInstrInfo &TII = *Fn.getSubtarget().getInstrInfo();
const TargetRegisterInfo &TRI = *Fn.getSubtarget().getRegisterInfo();
const TargetFrameLowering *TFI = Fn.getSubtarget().getFrameLowering();
- unsigned FrameSetupOpcode = TII.getCallFrameSetupOpcode();
- unsigned FrameDestroyOpcode = TII.getCallFrameDestroyOpcode();
if (RS && FrameIndexEliminationScavenging)
RS->enterBasicBlock(*BB);
@@ -1059,11 +1060,9 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn,
for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ) {
- if (I->getOpcode() == FrameSetupOpcode ||
- I->getOpcode() == FrameDestroyOpcode) {
- InsideCallSequence = (I->getOpcode() == FrameSetupOpcode);
+ if (TII.isFrameInstr(*I)) {
+ InsideCallSequence = TII.isFrameSetup(*I);
SPAdj += TII.getSPAdjust(*I);
-
I = TFI->eliminateCallFramePseudoInstr(Fn, *BB, I);
continue;
}
@@ -1151,90 +1150,3 @@ void PEI::replaceFrameIndices(MachineBasicBlock *BB, MachineFunction &Fn,
RS->forward(MI);
}
}
-
-/// doScavengeFrameVirtualRegs - Replace all frame index virtual registers
-/// with physical registers. Use the register scavenger to find an
-/// appropriate register to use.
-///
-/// 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.
-static void
-doScavengeFrameVirtualRegs(MachineFunction &MF, RegScavenger *RS) {
- // Run through the instructions and find any virtual registers.
- MachineRegisterInfo &MRI = MF.getRegInfo();
- for (MachineBasicBlock &MBB : MF) {
- RS->enterBasicBlock(MBB);
-
- int SPAdj = 0;
-
- // The instruction stream may change in the loop, so check MBB.end()
- // directly.
- for (MachineBasicBlock::iterator I = MBB.begin(); I != MBB.end(); ) {
- // 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 MBB.
- if (I == MachineBasicBlock::iterator(nullptr))
- I = MBB.begin();
-
- const MachineInstr &MI = *I;
- MachineBasicBlock::iterator J = std::next(I);
- MachineBasicBlock::iterator P =
- I == MBB.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
- // defined by this instruction, and if so, registers killed by this
- // instruction are available, and defined registers are not.
- RS->forward(I);
-
- for (const MachineOperand &MO : MI.operands()) {
- if (!MO.isReg())
- continue;
- unsigned Reg = MO.getReg();
- if (!TargetRegisterInfo::isVirtualRegister(Reg))
- continue;
-
- // When we first encounter a new virtual register, it
- // must be a definition.
- assert(MO.isDef() && "frame index virtual missing def!");
- // Scavenge a new scratch register
- const TargetRegisterClass *RC = MRI.getRegClass(Reg);
- unsigned ScratchReg = RS->scavengeRegister(RC, J, SPAdj);
-
- ++NumScavengedRegs;
-
- // Replace this reference to the virtual register with the
- // scratch register.
- assert(ScratchReg && "Missing scratch register!");
- MRI.replaceRegWith(Reg, 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->setRegUsed(ScratchReg);
- }
-
- // If the scavenger needed to use one of its spill slots, the
- // 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 != std::prev(J)) {
- MBB.splice(J, &MBB, I);
-
- // Before we move I, we need to prepare the RS to visit I again.
- // Specifically, RS will assert if it sees uses of registers that
- // it believes are undefined. Because we have already processed
- // register kills in I, when it visits I again, it will believe that
- // those registers are undefined. To avoid this situation, unprocess
- // the instruction I.
- assert(RS->getCurrentPosition() == I &&
- "The register scavenger has an unexpected position");
- I = P;
- RS->unprocess(P);
- } else
- ++I;
- }
- }
-}