First step of huge frame-related refactoring: move emit{Prologue,Epilogue} out of TargetRegisterInfo to TargetFrameInfo, which is definitely much better suitable place
llvm-svn: 119097
diff --git a/llvm/lib/Target/X86/X86FrameInfo.cpp b/llvm/lib/Target/X86/X86FrameInfo.cpp
new file mode 100644
index 0000000..98c579b
--- /dev/null
+++ b/llvm/lib/Target/X86/X86FrameInfo.cpp
@@ -0,0 +1,736 @@
+//=======- X86FrameInfo.cpp - X86 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 X86 implementation of TargetFrameInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "X86FrameInfo.h"
+#include "X86InstrBuilder.h"
+#include "X86InstrInfo.h"
+#include "X86MachineFunctionInfo.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;
+
+// FIXME: completely move here.
+extern cl::opt<bool> ForceStackAlign;
+
+static unsigned getSUBriOpcode(unsigned is64Bit, int64_t Imm) {
+ if (is64Bit) {
+ if (isInt<8>(Imm))
+ return X86::SUB64ri8;
+ return X86::SUB64ri32;
+ } else {
+ if (isInt<8>(Imm))
+ return X86::SUB32ri8;
+ return X86::SUB32ri;
+ }
+}
+
+static unsigned getADDriOpcode(unsigned is64Bit, int64_t Imm) {
+ if (is64Bit) {
+ if (isInt<8>(Imm))
+ return X86::ADD64ri8;
+ return X86::ADD64ri32;
+ } else {
+ if (isInt<8>(Imm))
+ return X86::ADD32ri8;
+ return X86::ADD32ri;
+ }
+}
+
+/// emitSPUpdate - Emit a series of instructions to increment / decrement the
+/// stack pointer by a constant value.
+static
+void emitSPUpdate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
+ unsigned StackPtr, int64_t NumBytes, bool Is64Bit,
+ const TargetInstrInfo &TII) {
+ bool isSub = NumBytes < 0;
+ uint64_t Offset = isSub ? -NumBytes : NumBytes;
+ unsigned Opc = isSub ?
+ getSUBriOpcode(Is64Bit, Offset) :
+ getADDriOpcode(Is64Bit, Offset);
+ uint64_t Chunk = (1LL << 31) - 1;
+ DebugLoc DL = MBB.findDebugLoc(MBBI);
+
+ while (Offset) {
+ uint64_t ThisVal = (Offset > Chunk) ? Chunk : Offset;
+ MachineInstr *MI =
+ BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr)
+ .addReg(StackPtr)
+ .addImm(ThisVal);
+ MI->getOperand(3).setIsDead(); // The EFLAGS implicit def is dead.
+ Offset -= ThisVal;
+ }
+}
+
+/// mergeSPUpdatesUp - Merge two stack-manipulating instructions upper iterator.
+static
+void mergeSPUpdatesUp(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
+ unsigned StackPtr, uint64_t *NumBytes = NULL) {
+ if (MBBI == MBB.begin()) return;
+
+ MachineBasicBlock::iterator PI = prior(MBBI);
+ unsigned Opc = PI->getOpcode();
+ if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
+ Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
+ PI->getOperand(0).getReg() == StackPtr) {
+ if (NumBytes)
+ *NumBytes += PI->getOperand(2).getImm();
+ MBB.erase(PI);
+ } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
+ Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
+ PI->getOperand(0).getReg() == StackPtr) {
+ if (NumBytes)
+ *NumBytes -= PI->getOperand(2).getImm();
+ MBB.erase(PI);
+ }
+}
+
+/// mergeSPUpdatesDown - Merge two stack-manipulating instructions lower iterator.
+static
+void mergeSPUpdatesDown(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ unsigned StackPtr, uint64_t *NumBytes = NULL) {
+ // FIXME: THIS ISN'T RUN!!!
+ return;
+
+ if (MBBI == MBB.end()) return;
+
+ MachineBasicBlock::iterator NI = llvm::next(MBBI);
+ if (NI == MBB.end()) return;
+
+ unsigned Opc = NI->getOpcode();
+ if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
+ Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
+ NI->getOperand(0).getReg() == StackPtr) {
+ if (NumBytes)
+ *NumBytes -= NI->getOperand(2).getImm();
+ MBB.erase(NI);
+ MBBI = NI;
+ } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
+ Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
+ NI->getOperand(0).getReg() == StackPtr) {
+ if (NumBytes)
+ *NumBytes += NI->getOperand(2).getImm();
+ MBB.erase(NI);
+ MBBI = NI;
+ }
+}
+
+/// mergeSPUpdates - Checks the instruction before/after the passed
+/// instruction. If it is an ADD/SUB instruction it is deleted argument and the
+/// stack adjustment is returned as a positive value for ADD and a negative for
+/// SUB.
+static int mergeSPUpdates(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MBBI,
+ unsigned StackPtr,
+ bool doMergeWithPrevious) {
+ if ((doMergeWithPrevious && MBBI == MBB.begin()) ||
+ (!doMergeWithPrevious && MBBI == MBB.end()))
+ return 0;
+
+ MachineBasicBlock::iterator PI = doMergeWithPrevious ? prior(MBBI) : MBBI;
+ MachineBasicBlock::iterator NI = doMergeWithPrevious ? 0 : llvm::next(MBBI);
+ unsigned Opc = PI->getOpcode();
+ int Offset = 0;
+
+ if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
+ Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
+ PI->getOperand(0).getReg() == StackPtr){
+ Offset += PI->getOperand(2).getImm();
+ MBB.erase(PI);
+ if (!doMergeWithPrevious) MBBI = NI;
+ } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
+ Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
+ PI->getOperand(0).getReg() == StackPtr) {
+ Offset -= PI->getOperand(2).getImm();
+ MBB.erase(PI);
+ if (!doMergeWithPrevious) MBBI = NI;
+ }
+
+ return Offset;
+}
+
+static bool isEAXLiveIn(MachineFunction &MF) {
+ for (MachineRegisterInfo::livein_iterator II = MF.getRegInfo().livein_begin(),
+ EE = MF.getRegInfo().livein_end(); II != EE; ++II) {
+ unsigned Reg = II->first;
+
+ if (Reg == X86::EAX || Reg == X86::AX ||
+ Reg == X86::AH || Reg == X86::AL)
+ return true;
+ }
+
+ return false;
+}
+
+void X86FrameInfo::emitCalleeSavedFrameMoves(MachineFunction &MF,
+ MCSymbol *Label,
+ unsigned FramePtr) const {
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ const X86RegisterInfo *RegInfo =
+ static_cast<const X86RegisterInfo*>(MF.getTarget().getRegisterInfo());
+ MachineModuleInfo &MMI = MF.getMMI();
+
+ // Add callee saved registers to move list.
+ const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
+ if (CSI.empty()) return;
+
+ std::vector<MachineMove> &Moves = MMI.getFrameMoves();
+ const TargetData *TD = MF.getTarget().getTargetData();
+ bool HasFP = RegInfo->hasFP(MF);
+
+ // Calculate amount of bytes used for return address storing.
+ int stackGrowth =
+ (MF.getTarget().getFrameInfo()->getStackGrowthDirection() ==
+ TargetFrameInfo::StackGrowsUp ?
+ TD->getPointerSize() : -TD->getPointerSize());
+
+ // FIXME: This is dirty hack. The code itself is pretty mess right now.
+ // It should be rewritten from scratch and generalized sometimes.
+
+ // Determine maximum offset (minumum due to stack growth).
+ int64_t MaxOffset = 0;
+ for (std::vector<CalleeSavedInfo>::const_iterator
+ I = CSI.begin(), E = CSI.end(); I != E; ++I)
+ MaxOffset = std::min(MaxOffset,
+ MFI->getObjectOffset(I->getFrameIdx()));
+
+ // Calculate offsets.
+ int64_t saveAreaOffset = (HasFP ? 3 : 2) * stackGrowth;
+ for (std::vector<CalleeSavedInfo>::const_iterator
+ I = CSI.begin(), E = CSI.end(); I != E; ++I) {
+ int64_t Offset = MFI->getObjectOffset(I->getFrameIdx());
+ unsigned Reg = I->getReg();
+ Offset = MaxOffset - Offset + saveAreaOffset;
+
+ // Don't output a new machine move if we're re-saving the frame
+ // pointer. This happens when the PrologEpilogInserter has inserted an extra
+ // "PUSH" of the frame pointer -- the "emitPrologue" method automatically
+ // generates one when frame pointers are used. If we generate a "machine
+ // move" for this extra "PUSH", the linker will lose track of the fact that
+ // the frame pointer should have the value of the first "PUSH" when it's
+ // trying to unwind.
+ //
+ // FIXME: This looks inelegant. It's possibly correct, but it's covering up
+ // another bug. I.e., one where we generate a prolog like this:
+ //
+ // pushl %ebp
+ // movl %esp, %ebp
+ // pushl %ebp
+ // pushl %esi
+ // ...
+ //
+ // The immediate re-push of EBP is unnecessary. At the least, it's an
+ // optimization bug. EBP can be used as a scratch register in certain
+ // cases, but probably not when we have a frame pointer.
+ if (HasFP && FramePtr == Reg)
+ continue;
+
+ MachineLocation CSDst(MachineLocation::VirtualFP, Offset);
+ MachineLocation CSSrc(Reg);
+ Moves.push_back(MachineMove(Label, CSDst, CSSrc));
+ }
+}
+
+/// emitPrologue - Push callee-saved registers onto the stack, which
+/// automatically adjust the stack pointer. Adjust the stack pointer to allocate
+/// space for local variables. Also emit labels used by the exception handler to
+/// generate the exception handling frames.
+void X86FrameInfo::emitPrologue(MachineFunction &MF) const {
+ MachineBasicBlock &MBB = MF.front(); // Prologue goes in entry BB.
+ MachineBasicBlock::iterator MBBI = MBB.begin();
+ MachineFrameInfo *MFI = MF.getFrameInfo();
+ const Function *Fn = MF.getFunction();
+ const X86Subtarget *Subtarget = &MF.getTarget().getSubtarget<X86Subtarget>();
+ const X86RegisterInfo *RegInfo =
+ static_cast<const X86RegisterInfo*>(MF.getTarget().getRegisterInfo());
+ const X86InstrInfo &TII =
+ *static_cast<const X86InstrInfo*>(MF.getTarget().getInstrInfo());
+ MachineModuleInfo &MMI = MF.getMMI();
+ X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
+ bool needsFrameMoves = MMI.hasDebugInfo() ||
+ !Fn->doesNotThrow() || UnwindTablesMandatory;
+ uint64_t MaxAlign = MFI->getMaxAlignment(); // Desired stack alignment.
+ uint64_t StackSize = MFI->getStackSize(); // Number of bytes to allocate.
+ bool HasFP = RegInfo->hasFP(MF);
+ bool Is64Bit = STI.is64Bit();
+ bool IsWin64 = STI.isTargetWin64();
+ unsigned StackAlign = getStackAlignment();
+ unsigned SlotSize = RegInfo->getSlotSize();
+ unsigned FramePtr = RegInfo->getFrameRegister(MF);
+ unsigned StackPtr = RegInfo->getStackRegister();
+
+ DebugLoc DL;
+
+ // If we're forcing a stack realignment we can't rely on just the frame
+ // info, we need to know the ABI stack alignment as well in case we
+ // have a call out. Otherwise just make sure we have some alignment - we'll
+ // go with the minimum SlotSize.
+ if (ForceStackAlign) {
+ if (MFI->hasCalls())
+ MaxAlign = (StackAlign > MaxAlign) ? StackAlign : MaxAlign;
+ else if (MaxAlign < SlotSize)
+ MaxAlign = SlotSize;
+ }
+
+ // Add RETADDR move area to callee saved frame size.
+ int TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta();
+ if (TailCallReturnAddrDelta < 0)
+ X86FI->setCalleeSavedFrameSize(
+ X86FI->getCalleeSavedFrameSize() - TailCallReturnAddrDelta);
+
+ // If this is x86-64 and the Red Zone is not disabled, if we are a leaf
+ // function, and use up to 128 bytes of stack space, don't have a frame
+ // pointer, calls, or dynamic alloca then we do not need to adjust the
+ // stack pointer (we fit in the Red Zone).
+ if (Is64Bit && !Fn->hasFnAttr(Attribute::NoRedZone) &&
+ !RegInfo->needsStackRealignment(MF) &&
+ !MFI->hasVarSizedObjects() && // No dynamic alloca.
+ !MFI->adjustsStack() && // No calls.
+ !IsWin64) { // Win64 has no Red Zone
+ uint64_t MinSize = X86FI->getCalleeSavedFrameSize();
+ if (HasFP) MinSize += SlotSize;
+ StackSize = std::max(MinSize, StackSize > 128 ? StackSize - 128 : 0);
+ MFI->setStackSize(StackSize);
+ } else if (IsWin64) {
+ // We need to always allocate 32 bytes as register spill area.
+ // FIXME: We might reuse these 32 bytes for leaf functions.
+ StackSize += 32;
+ MFI->setStackSize(StackSize);
+ }
+
+ // Insert stack pointer adjustment for later moving of return addr. Only
+ // applies to tail call optimized functions where the callee argument stack
+ // size is bigger than the callers.
+ if (TailCallReturnAddrDelta < 0) {
+ MachineInstr *MI =
+ BuildMI(MBB, MBBI, DL,
+ TII.get(getSUBriOpcode(Is64Bit, -TailCallReturnAddrDelta)),
+ StackPtr)
+ .addReg(StackPtr)
+ .addImm(-TailCallReturnAddrDelta);
+ MI->getOperand(3).setIsDead(); // The EFLAGS implicit def is dead.
+ }
+
+ // Mapping for machine moves:
+ //
+ // DST: VirtualFP AND
+ // SRC: VirtualFP => DW_CFA_def_cfa_offset
+ // ELSE => DW_CFA_def_cfa
+ //
+ // SRC: VirtualFP AND
+ // DST: Register => DW_CFA_def_cfa_register
+ //
+ // ELSE
+ // OFFSET < 0 => DW_CFA_offset_extended_sf
+ // REG < 64 => DW_CFA_offset + Reg
+ // ELSE => DW_CFA_offset_extended
+
+ std::vector<MachineMove> &Moves = MMI.getFrameMoves();
+ const TargetData *TD = MF.getTarget().getTargetData();
+ uint64_t NumBytes = 0;
+ int stackGrowth = -TD->getPointerSize();
+
+ if (HasFP) {
+ // Calculate required stack adjustment.
+ uint64_t FrameSize = StackSize - SlotSize;
+ if (RegInfo->needsStackRealignment(MF))
+ FrameSize = (FrameSize + MaxAlign - 1) / MaxAlign * MaxAlign;
+
+ NumBytes = FrameSize - X86FI->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 EBP/RBP into the appropriate stack slot.
+ BuildMI(MBB, MBBI, DL, TII.get(Is64Bit ? X86::PUSH64r : X86::PUSH32r))
+ .addReg(FramePtr, RegState::Kill);
+
+ if (needsFrameMoves) {
+ // Mark the place where EBP/RBP was saved.
+ MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol();
+ BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(FrameLabel);
+
+ // Define the current CFA rule to use the provided offset.
+ if (StackSize) {
+ MachineLocation SPDst(MachineLocation::VirtualFP);
+ MachineLocation SPSrc(MachineLocation::VirtualFP, 2 * stackGrowth);
+ Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc));
+ } else {
+ // FIXME: Verify & implement for FP
+ MachineLocation SPDst(StackPtr);
+ MachineLocation SPSrc(StackPtr, stackGrowth);
+ Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc));
+ }
+
+ // Change the rule for the FramePtr to be an "offset" rule.
+ MachineLocation FPDst(MachineLocation::VirtualFP, 2 * stackGrowth);
+ MachineLocation FPSrc(FramePtr);
+ Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc));
+ }
+
+ // Update EBP with the new base value...
+ BuildMI(MBB, MBBI, DL,
+ TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), FramePtr)
+ .addReg(StackPtr);
+
+ if (needsFrameMoves) {
+ // Mark effective beginning of when frame pointer becomes valid.
+ MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol();
+ BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(FrameLabel);
+
+ // Define the current CFA to use the EBP/RBP register.
+ MachineLocation FPDst(FramePtr);
+ MachineLocation FPSrc(MachineLocation::VirtualFP);
+ Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc));
+ }
+
+ // 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(FramePtr);
+
+ // Realign stack
+ if (RegInfo->needsStackRealignment(MF)) {
+ MachineInstr *MI =
+ BuildMI(MBB, MBBI, DL,
+ TII.get(Is64Bit ? X86::AND64ri32 : X86::AND32ri),
+ StackPtr).addReg(StackPtr).addImm(-MaxAlign);
+
+ // The EFLAGS implicit def is dead.
+ MI->getOperand(3).setIsDead();
+ }
+ } else {
+ NumBytes = StackSize - X86FI->getCalleeSavedFrameSize();
+ }
+
+ // Skip the callee-saved push instructions.
+ bool PushedRegs = false;
+ int StackOffset = 2 * stackGrowth;
+
+ while (MBBI != MBB.end() &&
+ (MBBI->getOpcode() == X86::PUSH32r ||
+ MBBI->getOpcode() == X86::PUSH64r)) {
+ PushedRegs = true;
+ ++MBBI;
+
+ if (!HasFP && needsFrameMoves) {
+ // Mark callee-saved push instruction.
+ MCSymbol *Label = MMI.getContext().CreateTempSymbol();
+ BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(Label);
+
+ // Define the current CFA rule to use the provided offset.
+ unsigned Ptr = StackSize ?
+ MachineLocation::VirtualFP : StackPtr;
+ MachineLocation SPDst(Ptr);
+ MachineLocation SPSrc(Ptr, StackOffset);
+ Moves.push_back(MachineMove(Label, SPDst, SPSrc));
+ StackOffset += stackGrowth;
+ }
+ }
+
+ DL = MBB.findDebugLoc(MBBI);
+
+ // If there is an SUB32ri of ESP immediately before this instruction, merge
+ // the two. This can be the case when tail call elimination is enabled and
+ // the callee has more arguments then the caller.
+ NumBytes -= mergeSPUpdates(MBB, MBBI, StackPtr, true);
+
+ // If there is an ADD32ri or SUB32ri of ESP immediately after this
+ // instruction, merge the two instructions.
+ mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes);
+
+ // Adjust stack pointer: ESP -= numbytes.
+
+ // Windows and cygwin/mingw require a prologue helper routine when allocating
+ // more than 4K bytes on the stack. Windows uses __chkstk and cygwin/mingw
+ // uses __alloca. __alloca and the 32-bit version of __chkstk will probe the
+ // stack and adjust the stack pointer in one go. The 64-bit version of
+ // __chkstk is only responsible for probing the stack. The 64-bit prologue is
+ // responsible for adjusting the stack pointer. Touching the stack at 4K
+ // increments is necessary to ensure that the guard pages used by the OS
+ // virtual memory manager are allocated in correct sequence.
+ if (NumBytes >= 4096 &&
+ (Subtarget->isTargetCygMing() || Subtarget->isTargetWin32())) {
+ // Check whether EAX is livein for this function.
+ bool isEAXAlive = isEAXLiveIn(MF);
+
+ const char *StackProbeSymbol =
+ Subtarget->isTargetWindows() ? "_chkstk" : "_alloca";
+ unsigned CallOp = Is64Bit ? X86::CALL64pcrel32 : X86::CALLpcrel32;
+ if (!isEAXAlive) {
+ BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
+ .addImm(NumBytes);
+ BuildMI(MBB, MBBI, DL, TII.get(CallOp))
+ .addExternalSymbol(StackProbeSymbol)
+ .addReg(StackPtr, RegState::Define | RegState::Implicit)
+ .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
+ } else {
+ // Save EAX
+ BuildMI(MBB, MBBI, DL, TII.get(X86::PUSH32r))
+ .addReg(X86::EAX, RegState::Kill);
+
+ // Allocate NumBytes-4 bytes on stack. We'll also use 4 already
+ // allocated bytes for EAX.
+ BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
+ .addImm(NumBytes - 4);
+ BuildMI(MBB, MBBI, DL, TII.get(CallOp))
+ .addExternalSymbol(StackProbeSymbol)
+ .addReg(StackPtr, RegState::Define | RegState::Implicit)
+ .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
+
+ // Restore EAX
+ MachineInstr *MI = addRegOffset(BuildMI(MF, DL, TII.get(X86::MOV32rm),
+ X86::EAX),
+ StackPtr, false, NumBytes - 4);
+ MBB.insert(MBBI, MI);
+ }
+ } else if (NumBytes >= 4096 && Subtarget->isTargetWin64()) {
+ // Sanity check that EAX is not livein for this function. It should
+ // should not be, so throw an assert.
+ assert(!isEAXLiveIn(MF) && "EAX is livein in the Win64 case!");
+
+ // Handle the 64-bit Windows ABI case where we need to call __chkstk.
+ // Function prologue is responsible for adjusting the stack pointer.
+ BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
+ .addImm(NumBytes);
+ BuildMI(MBB, MBBI, DL, TII.get(X86::WINCALL64pcrel32))
+ .addExternalSymbol("__chkstk")
+ .addReg(StackPtr, RegState::Define | RegState::Implicit);
+ emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
+ } else if (NumBytes)
+ emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
+
+ if ((NumBytes || PushedRegs) && needsFrameMoves) {
+ // Mark end of stack pointer adjustment.
+ MCSymbol *Label = MMI.getContext().CreateTempSymbol();
+ BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(Label);
+
+ if (!HasFP && NumBytes) {
+ // Define the current CFA rule to use the provided offset.
+ if (StackSize) {
+ MachineLocation SPDst(MachineLocation::VirtualFP);
+ MachineLocation SPSrc(MachineLocation::VirtualFP,
+ -StackSize + stackGrowth);
+ Moves.push_back(MachineMove(Label, SPDst, SPSrc));
+ } else {
+ // FIXME: Verify & implement for FP
+ MachineLocation SPDst(StackPtr);
+ MachineLocation SPSrc(StackPtr, stackGrowth);
+ Moves.push_back(MachineMove(Label, SPDst, SPSrc));
+ }
+ }
+
+ // Emit DWARF info specifying the offsets of the callee-saved registers.
+ if (PushedRegs)
+ emitCalleeSavedFrameMoves(MF, Label, HasFP ? FramePtr : StackPtr);
+ }
+}
+
+void X86FrameInfo::emitEpilogue(MachineFunction &MF,
+ MachineBasicBlock &MBB) const {
+ const MachineFrameInfo *MFI = MF.getFrameInfo();
+ X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
+ const X86RegisterInfo *RegInfo =
+ static_cast<const X86RegisterInfo*>(MF.getTarget().getRegisterInfo());
+ const X86InstrInfo &TII =
+ *static_cast<const X86InstrInfo*>(MF.getTarget().getInstrInfo());
+ MachineBasicBlock::iterator MBBI = prior(MBB.end());
+ unsigned RetOpcode = MBBI->getOpcode();
+ DebugLoc DL = MBBI->getDebugLoc();
+ bool Is64Bit = STI.is64Bit();
+ unsigned StackAlign = getStackAlignment();
+ unsigned SlotSize = RegInfo->getSlotSize();
+ unsigned FramePtr = RegInfo->getFrameRegister(MF);
+ unsigned StackPtr = RegInfo->getStackRegister();
+
+ switch (RetOpcode) {
+ default:
+ llvm_unreachable("Can only insert epilog into returning blocks");
+ case X86::RET:
+ case X86::RETI:
+ case X86::TCRETURNdi:
+ case X86::TCRETURNri:
+ case X86::TCRETURNmi:
+ case X86::TCRETURNdi64:
+ case X86::TCRETURNri64:
+ case X86::TCRETURNmi64:
+ case X86::EH_RETURN:
+ case X86::EH_RETURN64:
+ break; // These are ok
+ }
+
+ // Get the number of bytes to allocate from the FrameInfo.
+ uint64_t StackSize = MFI->getStackSize();
+ uint64_t MaxAlign = MFI->getMaxAlignment();
+ unsigned CSSize = X86FI->getCalleeSavedFrameSize();
+ uint64_t NumBytes = 0;
+
+ // If we're forcing a stack realignment we can't rely on just the frame
+ // info, we need to know the ABI stack alignment as well in case we
+ // have a call out. Otherwise just make sure we have some alignment - we'll
+ // go with the minimum.
+ if (ForceStackAlign) {
+ if (MFI->hasCalls())
+ MaxAlign = (StackAlign > MaxAlign) ? StackAlign : MaxAlign;
+ else
+ MaxAlign = MaxAlign ? MaxAlign : 4;
+ }
+
+ if (RegInfo->hasFP(MF)) {
+ // Calculate required stack adjustment.
+ uint64_t FrameSize = StackSize - SlotSize;
+ if (RegInfo->needsStackRealignment(MF))
+ FrameSize = (FrameSize + MaxAlign - 1)/MaxAlign*MaxAlign;
+
+ NumBytes = FrameSize - CSSize;
+
+ // Pop EBP.
+ BuildMI(MBB, MBBI, DL,
+ TII.get(Is64Bit ? X86::POP64r : X86::POP32r), FramePtr);
+ } else {
+ NumBytes = StackSize - CSSize;
+ }
+
+ // Skip the callee-saved pop instructions.
+ MachineBasicBlock::iterator LastCSPop = MBBI;
+ while (MBBI != MBB.begin()) {
+ MachineBasicBlock::iterator PI = prior(MBBI);
+ unsigned Opc = PI->getOpcode();
+
+ if (Opc != X86::POP32r && Opc != X86::POP64r &&
+ !PI->getDesc().isTerminator())
+ break;
+
+ --MBBI;
+ }
+
+ DL = MBBI->getDebugLoc();
+
+ // If there is an ADD32ri or SUB32ri of ESP immediately before this
+ // instruction, merge the two instructions.
+ if (NumBytes || MFI->hasVarSizedObjects())
+ mergeSPUpdatesUp(MBB, MBBI, StackPtr, &NumBytes);
+
+ // If dynamic alloca is used, then reset esp to point to the last callee-saved
+ // slot before popping them off! Same applies for the case, when stack was
+ // realigned.
+ if (RegInfo->needsStackRealignment(MF)) {
+ // We cannot use LEA here, because stack pointer was realigned. We need to
+ // deallocate local frame back.
+ if (CSSize) {
+ emitSPUpdate(MBB, MBBI, StackPtr, NumBytes, Is64Bit, TII);
+ MBBI = prior(LastCSPop);
+ }
+
+ BuildMI(MBB, MBBI, DL,
+ TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr),
+ StackPtr).addReg(FramePtr);
+ } else if (MFI->hasVarSizedObjects()) {
+ if (CSSize) {
+ unsigned Opc = Is64Bit ? X86::LEA64r : X86::LEA32r;
+ MachineInstr *MI =
+ addRegOffset(BuildMI(MF, DL, TII.get(Opc), StackPtr),
+ FramePtr, false, -CSSize);
+ MBB.insert(MBBI, MI);
+ } else {
+ BuildMI(MBB, MBBI, DL,
+ TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), StackPtr)
+ .addReg(FramePtr);
+ }
+ } else if (NumBytes) {
+ // Adjust stack pointer back: ESP += numbytes.
+ emitSPUpdate(MBB, MBBI, StackPtr, NumBytes, Is64Bit, TII);
+ }
+
+ // We're returning from function via eh_return.
+ if (RetOpcode == X86::EH_RETURN || RetOpcode == X86::EH_RETURN64) {
+ MBBI = prior(MBB.end());
+ MachineOperand &DestAddr = MBBI->getOperand(0);
+ assert(DestAddr.isReg() && "Offset should be in register!");
+ BuildMI(MBB, MBBI, DL,
+ TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr),
+ StackPtr).addReg(DestAddr.getReg());
+ } else if (RetOpcode == X86::TCRETURNri || RetOpcode == X86::TCRETURNdi ||
+ RetOpcode == X86::TCRETURNmi ||
+ RetOpcode == X86::TCRETURNri64 || RetOpcode == X86::TCRETURNdi64 ||
+ RetOpcode == X86::TCRETURNmi64) {
+ bool isMem = RetOpcode == X86::TCRETURNmi || RetOpcode == X86::TCRETURNmi64;
+ // Tail call return: adjust the stack pointer and jump to callee.
+ MBBI = prior(MBB.end());
+ MachineOperand &JumpTarget = MBBI->getOperand(0);
+ MachineOperand &StackAdjust = MBBI->getOperand(isMem ? 5 : 1);
+ assert(StackAdjust.isImm() && "Expecting immediate value.");
+
+ // Adjust stack pointer.
+ int StackAdj = StackAdjust.getImm();
+ int MaxTCDelta = X86FI->getTCReturnAddrDelta();
+ int Offset = 0;
+ assert(MaxTCDelta <= 0 && "MaxTCDelta should never be positive");
+
+ // Incoporate the retaddr area.
+ Offset = StackAdj-MaxTCDelta;
+ assert(Offset >= 0 && "Offset should never be negative");
+
+ if (Offset) {
+ // Check for possible merge with preceeding ADD instruction.
+ Offset += mergeSPUpdates(MBB, MBBI, StackPtr, true);
+ emitSPUpdate(MBB, MBBI, StackPtr, Offset, Is64Bit, TII);
+ }
+
+ // Jump to label or value in register.
+ if (RetOpcode == X86::TCRETURNdi || RetOpcode == X86::TCRETURNdi64) {
+ BuildMI(MBB, MBBI, DL, TII.get((RetOpcode == X86::TCRETURNdi)
+ ? X86::TAILJMPd : X86::TAILJMPd64)).
+ addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset(),
+ JumpTarget.getTargetFlags());
+ } else if (RetOpcode == X86::TCRETURNmi || RetOpcode == X86::TCRETURNmi64) {
+ MachineInstrBuilder MIB =
+ BuildMI(MBB, MBBI, DL, TII.get((RetOpcode == X86::TCRETURNmi)
+ ? X86::TAILJMPm : X86::TAILJMPm64));
+ for (unsigned i = 0; i != 5; ++i)
+ MIB.addOperand(MBBI->getOperand(i));
+ } else if (RetOpcode == X86::TCRETURNri64) {
+ BuildMI(MBB, MBBI, DL, TII.get(X86::TAILJMPr64)).
+ addReg(JumpTarget.getReg(), RegState::Kill);
+ } else {
+ BuildMI(MBB, MBBI, DL, TII.get(X86::TAILJMPr)).
+ addReg(JumpTarget.getReg(), RegState::Kill);
+ }
+
+ MachineInstr *NewMI = prior(MBBI);
+ for (unsigned i = 2, e = MBBI->getNumOperands(); i != e; ++i)
+ NewMI->addOperand(MBBI->getOperand(i));
+
+ // Delete the pseudo instruction TCRETURN.
+ MBB.erase(MBBI);
+ } else if ((RetOpcode == X86::RET || RetOpcode == X86::RETI) &&
+ (X86FI->getTCReturnAddrDelta() < 0)) {
+ // Add the return addr area delta back since we are not tail calling.
+ int delta = -1*X86FI->getTCReturnAddrDelta();
+ MBBI = prior(MBB.end());
+
+ // Check for possible merge with preceeding ADD instruction.
+ delta += mergeSPUpdates(MBB, MBBI, StackPtr, true);
+ emitSPUpdate(MBB, MBBI, StackPtr, delta, Is64Bit, TII);
+ }
+}
diff --git a/llvm/lib/Target/X86/X86FrameInfo.h b/llvm/lib/Target/X86/X86FrameInfo.h
new file mode 100644
index 0000000..7828e17
--- /dev/null
+++ b/llvm/lib/Target/X86/X86FrameInfo.h
@@ -0,0 +1,46 @@
+//===-- X86TargetFrameInfo.h - Define TargetFrameInfo for X86 ---*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef X86_FRAMEINFO_H
+#define X86_FRAMEINFO_H
+
+#include "X86Subtarget.h"
+#include "llvm/Target/TargetFrameInfo.h"
+
+namespace llvm {
+ class MCSymbol;
+
+class X86FrameInfo : public TargetFrameInfo {
+protected:
+ const X86Subtarget &STI;
+
+public:
+ explicit X86FrameInfo(const X86Subtarget &sti)
+ : TargetFrameInfo(StackGrowsDown,
+ sti.getStackAlignment(),
+ (sti.isTargetWin64() ? -40 : (sti.is64Bit() ? -8 : -4))),
+ STI(sti) {
+ }
+
+ void emitCalleeSavedFrameMoves(MachineFunction &MF, MCSymbol *Label,
+ unsigned FramePtr) const;
+
+ /// emitProlog/emitEpilog - These methods insert prolog and epilog code into
+ /// the function.
+ void emitPrologue(MachineFunction &MF) const;
+ void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const;
+};
+
+} // End llvm namespace
+
+#endif
diff --git a/llvm/lib/Target/X86/X86RegisterInfo.cpp b/llvm/lib/Target/X86/X86RegisterInfo.cpp
index dfe73dc..0f505d1 100644
--- a/llvm/lib/Target/X86/X86RegisterInfo.cpp
+++ b/llvm/lib/Target/X86/X86RegisterInfo.cpp
@@ -41,7 +41,7 @@
#include "llvm/Support/CommandLine.h"
using namespace llvm;
-static cl::opt<bool>
+cl::opt<bool>
ForceStackAlign("force-align-stack",
cl::desc("Force align the stack to the minimum alignment"
" needed for the function."),
@@ -696,665 +696,6 @@
}
}
-/// emitSPUpdate - Emit a series of instructions to increment / decrement the
-/// stack pointer by a constant value.
-static
-void emitSPUpdate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
- unsigned StackPtr, int64_t NumBytes, bool Is64Bit,
- const TargetInstrInfo &TII) {
- bool isSub = NumBytes < 0;
- uint64_t Offset = isSub ? -NumBytes : NumBytes;
- unsigned Opc = isSub ?
- getSUBriOpcode(Is64Bit, Offset) :
- getADDriOpcode(Is64Bit, Offset);
- uint64_t Chunk = (1LL << 31) - 1;
- DebugLoc DL = MBB.findDebugLoc(MBBI);
-
- while (Offset) {
- uint64_t ThisVal = (Offset > Chunk) ? Chunk : Offset;
- MachineInstr *MI =
- BuildMI(MBB, MBBI, DL, TII.get(Opc), StackPtr)
- .addReg(StackPtr)
- .addImm(ThisVal);
- MI->getOperand(3).setIsDead(); // The EFLAGS implicit def is dead.
- Offset -= ThisVal;
- }
-}
-
-/// mergeSPUpdatesUp - Merge two stack-manipulating instructions upper iterator.
-static
-void mergeSPUpdatesUp(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI,
- unsigned StackPtr, uint64_t *NumBytes = NULL) {
- if (MBBI == MBB.begin()) return;
-
- MachineBasicBlock::iterator PI = prior(MBBI);
- unsigned Opc = PI->getOpcode();
- if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
- Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
- PI->getOperand(0).getReg() == StackPtr) {
- if (NumBytes)
- *NumBytes += PI->getOperand(2).getImm();
- MBB.erase(PI);
- } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
- Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
- PI->getOperand(0).getReg() == StackPtr) {
- if (NumBytes)
- *NumBytes -= PI->getOperand(2).getImm();
- MBB.erase(PI);
- }
-}
-
-/// mergeSPUpdatesDown - Merge two stack-manipulating instructions lower iterator.
-static
-void mergeSPUpdatesDown(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator &MBBI,
- unsigned StackPtr, uint64_t *NumBytes = NULL) {
- // FIXME: THIS ISN'T RUN!!!
- return;
-
- if (MBBI == MBB.end()) return;
-
- MachineBasicBlock::iterator NI = llvm::next(MBBI);
- if (NI == MBB.end()) return;
-
- unsigned Opc = NI->getOpcode();
- if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
- Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
- NI->getOperand(0).getReg() == StackPtr) {
- if (NumBytes)
- *NumBytes -= NI->getOperand(2).getImm();
- MBB.erase(NI);
- MBBI = NI;
- } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
- Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
- NI->getOperand(0).getReg() == StackPtr) {
- if (NumBytes)
- *NumBytes += NI->getOperand(2).getImm();
- MBB.erase(NI);
- MBBI = NI;
- }
-}
-
-/// mergeSPUpdates - Checks the instruction before/after the passed
-/// instruction. If it is an ADD/SUB instruction it is deleted argument and the
-/// stack adjustment is returned as a positive value for ADD and a negative for
-/// SUB.
-static int mergeSPUpdates(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator &MBBI,
- unsigned StackPtr,
- bool doMergeWithPrevious) {
- if ((doMergeWithPrevious && MBBI == MBB.begin()) ||
- (!doMergeWithPrevious && MBBI == MBB.end()))
- return 0;
-
- MachineBasicBlock::iterator PI = doMergeWithPrevious ? prior(MBBI) : MBBI;
- MachineBasicBlock::iterator NI = doMergeWithPrevious ? 0 : llvm::next(MBBI);
- unsigned Opc = PI->getOpcode();
- int Offset = 0;
-
- if ((Opc == X86::ADD64ri32 || Opc == X86::ADD64ri8 ||
- Opc == X86::ADD32ri || Opc == X86::ADD32ri8) &&
- PI->getOperand(0).getReg() == StackPtr){
- Offset += PI->getOperand(2).getImm();
- MBB.erase(PI);
- if (!doMergeWithPrevious) MBBI = NI;
- } else if ((Opc == X86::SUB64ri32 || Opc == X86::SUB64ri8 ||
- Opc == X86::SUB32ri || Opc == X86::SUB32ri8) &&
- PI->getOperand(0).getReg() == StackPtr) {
- Offset -= PI->getOperand(2).getImm();
- MBB.erase(PI);
- if (!doMergeWithPrevious) MBBI = NI;
- }
-
- return Offset;
-}
-
-void X86RegisterInfo::emitCalleeSavedFrameMoves(MachineFunction &MF,
- MCSymbol *Label,
- unsigned FramePtr) const {
- MachineFrameInfo *MFI = MF.getFrameInfo();
- MachineModuleInfo &MMI = MF.getMMI();
-
- // Add callee saved registers to move list.
- const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
- if (CSI.empty()) return;
-
- std::vector<MachineMove> &Moves = MMI.getFrameMoves();
- const TargetData *TD = MF.getTarget().getTargetData();
- bool HasFP = hasFP(MF);
-
- // Calculate amount of bytes used for return address storing.
- int stackGrowth =
- (MF.getTarget().getFrameInfo()->getStackGrowthDirection() ==
- TargetFrameInfo::StackGrowsUp ?
- TD->getPointerSize() : -TD->getPointerSize());
-
- // FIXME: This is dirty hack. The code itself is pretty mess right now.
- // It should be rewritten from scratch and generalized sometimes.
-
- // Determine maximum offset (minumum due to stack growth).
- int64_t MaxOffset = 0;
- for (std::vector<CalleeSavedInfo>::const_iterator
- I = CSI.begin(), E = CSI.end(); I != E; ++I)
- MaxOffset = std::min(MaxOffset,
- MFI->getObjectOffset(I->getFrameIdx()));
-
- // Calculate offsets.
- int64_t saveAreaOffset = (HasFP ? 3 : 2) * stackGrowth;
- for (std::vector<CalleeSavedInfo>::const_iterator
- I = CSI.begin(), E = CSI.end(); I != E; ++I) {
- int64_t Offset = MFI->getObjectOffset(I->getFrameIdx());
- unsigned Reg = I->getReg();
- Offset = MaxOffset - Offset + saveAreaOffset;
-
- // Don't output a new machine move if we're re-saving the frame
- // pointer. This happens when the PrologEpilogInserter has inserted an extra
- // "PUSH" of the frame pointer -- the "emitPrologue" method automatically
- // generates one when frame pointers are used. If we generate a "machine
- // move" for this extra "PUSH", the linker will lose track of the fact that
- // the frame pointer should have the value of the first "PUSH" when it's
- // trying to unwind.
- //
- // FIXME: This looks inelegant. It's possibly correct, but it's covering up
- // another bug. I.e., one where we generate a prolog like this:
- //
- // pushl %ebp
- // movl %esp, %ebp
- // pushl %ebp
- // pushl %esi
- // ...
- //
- // The immediate re-push of EBP is unnecessary. At the least, it's an
- // optimization bug. EBP can be used as a scratch register in certain
- // cases, but probably not when we have a frame pointer.
- if (HasFP && FramePtr == Reg)
- continue;
-
- MachineLocation CSDst(MachineLocation::VirtualFP, Offset);
- MachineLocation CSSrc(Reg);
- Moves.push_back(MachineMove(Label, CSDst, CSSrc));
- }
-}
-
-static bool isEAXLiveIn(MachineFunction &MF) {
- for (MachineRegisterInfo::livein_iterator II = MF.getRegInfo().livein_begin(),
- EE = MF.getRegInfo().livein_end(); II != EE; ++II) {
- unsigned Reg = II->first;
-
- if (Reg == X86::EAX || Reg == X86::AX ||
- Reg == X86::AH || Reg == X86::AL)
- return true;
- }
-
- return false;
-}
-
-/// emitPrologue - Push callee-saved registers onto the stack, which
-/// automatically adjust the stack pointer. Adjust the stack pointer to allocate
-/// space for local variables. Also emit labels used by the exception handler to
-/// generate the exception handling frames.
-void X86RegisterInfo::emitPrologue(MachineFunction &MF) const {
- MachineBasicBlock &MBB = MF.front(); // Prologue goes in entry BB.
- MachineBasicBlock::iterator MBBI = MBB.begin();
- MachineFrameInfo *MFI = MF.getFrameInfo();
- const Function *Fn = MF.getFunction();
- const X86Subtarget *Subtarget = &MF.getTarget().getSubtarget<X86Subtarget>();
- MachineModuleInfo &MMI = MF.getMMI();
- X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
- bool needsFrameMoves = MMI.hasDebugInfo() ||
- !Fn->doesNotThrow() || UnwindTablesMandatory;
- uint64_t MaxAlign = MFI->getMaxAlignment(); // Desired stack alignment.
- uint64_t StackSize = MFI->getStackSize(); // Number of bytes to allocate.
- bool HasFP = hasFP(MF);
- DebugLoc DL;
-
- // If we're forcing a stack realignment we can't rely on just the frame
- // info, we need to know the ABI stack alignment as well in case we
- // have a call out. Otherwise just make sure we have some alignment - we'll
- // go with the minimum SlotSize.
- if (ForceStackAlign) {
- if (MFI->hasCalls())
- MaxAlign = (StackAlign > MaxAlign) ? StackAlign : MaxAlign;
- else if (MaxAlign < SlotSize)
- MaxAlign = SlotSize;
- }
-
- // Add RETADDR move area to callee saved frame size.
- int TailCallReturnAddrDelta = X86FI->getTCReturnAddrDelta();
- if (TailCallReturnAddrDelta < 0)
- X86FI->setCalleeSavedFrameSize(
- X86FI->getCalleeSavedFrameSize() - TailCallReturnAddrDelta);
-
- // If this is x86-64 and the Red Zone is not disabled, if we are a leaf
- // function, and use up to 128 bytes of stack space, don't have a frame
- // pointer, calls, or dynamic alloca then we do not need to adjust the
- // stack pointer (we fit in the Red Zone).
- if (Is64Bit && !Fn->hasFnAttr(Attribute::NoRedZone) &&
- !needsStackRealignment(MF) &&
- !MFI->hasVarSizedObjects() && // No dynamic alloca.
- !MFI->adjustsStack() && // No calls.
- !IsWin64) { // Win64 has no Red Zone
- uint64_t MinSize = X86FI->getCalleeSavedFrameSize();
- if (HasFP) MinSize += SlotSize;
- StackSize = std::max(MinSize, StackSize > 128 ? StackSize - 128 : 0);
- MFI->setStackSize(StackSize);
- } else if (IsWin64) {
- // We need to always allocate 32 bytes as register spill area.
- // FIXME: We might reuse these 32 bytes for leaf functions.
- StackSize += 32;
- MFI->setStackSize(StackSize);
- }
-
- // Insert stack pointer adjustment for later moving of return addr. Only
- // applies to tail call optimized functions where the callee argument stack
- // size is bigger than the callers.
- if (TailCallReturnAddrDelta < 0) {
- MachineInstr *MI =
- BuildMI(MBB, MBBI, DL,
- TII.get(getSUBriOpcode(Is64Bit, -TailCallReturnAddrDelta)),
- StackPtr)
- .addReg(StackPtr)
- .addImm(-TailCallReturnAddrDelta);
- MI->getOperand(3).setIsDead(); // The EFLAGS implicit def is dead.
- }
-
- // Mapping for machine moves:
- //
- // DST: VirtualFP AND
- // SRC: VirtualFP => DW_CFA_def_cfa_offset
- // ELSE => DW_CFA_def_cfa
- //
- // SRC: VirtualFP AND
- // DST: Register => DW_CFA_def_cfa_register
- //
- // ELSE
- // OFFSET < 0 => DW_CFA_offset_extended_sf
- // REG < 64 => DW_CFA_offset + Reg
- // ELSE => DW_CFA_offset_extended
-
- std::vector<MachineMove> &Moves = MMI.getFrameMoves();
- const TargetData *TD = MF.getTarget().getTargetData();
- uint64_t NumBytes = 0;
- int stackGrowth = -TD->getPointerSize();
-
- if (HasFP) {
- // Calculate required stack adjustment.
- uint64_t FrameSize = StackSize - SlotSize;
- if (needsStackRealignment(MF))
- FrameSize = (FrameSize + MaxAlign - 1) / MaxAlign * MaxAlign;
-
- NumBytes = FrameSize - X86FI->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 EBP/RBP into the appropriate stack slot.
- BuildMI(MBB, MBBI, DL, TII.get(Is64Bit ? X86::PUSH64r : X86::PUSH32r))
- .addReg(FramePtr, RegState::Kill);
-
- if (needsFrameMoves) {
- // Mark the place where EBP/RBP was saved.
- MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol();
- BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(FrameLabel);
-
- // Define the current CFA rule to use the provided offset.
- if (StackSize) {
- MachineLocation SPDst(MachineLocation::VirtualFP);
- MachineLocation SPSrc(MachineLocation::VirtualFP, 2 * stackGrowth);
- Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc));
- } else {
- // FIXME: Verify & implement for FP
- MachineLocation SPDst(StackPtr);
- MachineLocation SPSrc(StackPtr, stackGrowth);
- Moves.push_back(MachineMove(FrameLabel, SPDst, SPSrc));
- }
-
- // Change the rule for the FramePtr to be an "offset" rule.
- MachineLocation FPDst(MachineLocation::VirtualFP, 2 * stackGrowth);
- MachineLocation FPSrc(FramePtr);
- Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc));
- }
-
- // Update EBP with the new base value...
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), FramePtr)
- .addReg(StackPtr);
-
- if (needsFrameMoves) {
- // Mark effective beginning of when frame pointer becomes valid.
- MCSymbol *FrameLabel = MMI.getContext().CreateTempSymbol();
- BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(FrameLabel);
-
- // Define the current CFA to use the EBP/RBP register.
- MachineLocation FPDst(FramePtr);
- MachineLocation FPSrc(MachineLocation::VirtualFP);
- Moves.push_back(MachineMove(FrameLabel, FPDst, FPSrc));
- }
-
- // 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(FramePtr);
-
- // Realign stack
- if (needsStackRealignment(MF)) {
- MachineInstr *MI =
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::AND64ri32 : X86::AND32ri),
- StackPtr).addReg(StackPtr).addImm(-MaxAlign);
-
- // The EFLAGS implicit def is dead.
- MI->getOperand(3).setIsDead();
- }
- } else {
- NumBytes = StackSize - X86FI->getCalleeSavedFrameSize();
- }
-
- // Skip the callee-saved push instructions.
- bool PushedRegs = false;
- int StackOffset = 2 * stackGrowth;
-
- while (MBBI != MBB.end() &&
- (MBBI->getOpcode() == X86::PUSH32r ||
- MBBI->getOpcode() == X86::PUSH64r)) {
- PushedRegs = true;
- ++MBBI;
-
- if (!HasFP && needsFrameMoves) {
- // Mark callee-saved push instruction.
- MCSymbol *Label = MMI.getContext().CreateTempSymbol();
- BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(Label);
-
- // Define the current CFA rule to use the provided offset.
- unsigned Ptr = StackSize ?
- MachineLocation::VirtualFP : StackPtr;
- MachineLocation SPDst(Ptr);
- MachineLocation SPSrc(Ptr, StackOffset);
- Moves.push_back(MachineMove(Label, SPDst, SPSrc));
- StackOffset += stackGrowth;
- }
- }
-
- DL = MBB.findDebugLoc(MBBI);
-
- // If there is an SUB32ri of ESP immediately before this instruction, merge
- // the two. This can be the case when tail call elimination is enabled and
- // the callee has more arguments then the caller.
- NumBytes -= mergeSPUpdates(MBB, MBBI, StackPtr, true);
-
- // If there is an ADD32ri or SUB32ri of ESP immediately after this
- // instruction, merge the two instructions.
- mergeSPUpdatesDown(MBB, MBBI, StackPtr, &NumBytes);
-
- // Adjust stack pointer: ESP -= numbytes.
-
- // Windows and cygwin/mingw require a prologue helper routine when allocating
- // more than 4K bytes on the stack. Windows uses __chkstk and cygwin/mingw
- // uses __alloca. __alloca and the 32-bit version of __chkstk will probe the
- // stack and adjust the stack pointer in one go. The 64-bit version of
- // __chkstk is only responsible for probing the stack. The 64-bit prologue is
- // responsible for adjusting the stack pointer. Touching the stack at 4K
- // increments is necessary to ensure that the guard pages used by the OS
- // virtual memory manager are allocated in correct sequence.
- if (NumBytes >= 4096 &&
- (Subtarget->isTargetCygMing() || Subtarget->isTargetWin32())) {
- // Check whether EAX is livein for this function.
- bool isEAXAlive = isEAXLiveIn(MF);
-
- const char *StackProbeSymbol =
- Subtarget->isTargetWindows() ? "_chkstk" : "_alloca";
- unsigned CallOp = Is64Bit ? X86::CALL64pcrel32 : X86::CALLpcrel32;
- if (!isEAXAlive) {
- BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
- .addImm(NumBytes);
- BuildMI(MBB, MBBI, DL, TII.get(CallOp))
- .addExternalSymbol(StackProbeSymbol)
- .addReg(StackPtr, RegState::Define | RegState::Implicit)
- .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
- } else {
- // Save EAX
- BuildMI(MBB, MBBI, DL, TII.get(X86::PUSH32r))
- .addReg(X86::EAX, RegState::Kill);
-
- // Allocate NumBytes-4 bytes on stack. We'll also use 4 already
- // allocated bytes for EAX.
- BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
- .addImm(NumBytes - 4);
- BuildMI(MBB, MBBI, DL, TII.get(CallOp))
- .addExternalSymbol(StackProbeSymbol)
- .addReg(StackPtr, RegState::Define | RegState::Implicit)
- .addReg(X86::EFLAGS, RegState::Define | RegState::Implicit);
-
- // Restore EAX
- MachineInstr *MI = addRegOffset(BuildMI(MF, DL, TII.get(X86::MOV32rm),
- X86::EAX),
- StackPtr, false, NumBytes - 4);
- MBB.insert(MBBI, MI);
- }
- } else if (NumBytes >= 4096 && Subtarget->isTargetWin64()) {
- // Sanity check that EAX is not livein for this function. It should
- // should not be, so throw an assert.
- assert(!isEAXLiveIn(MF) && "EAX is livein in the Win64 case!");
-
- // Handle the 64-bit Windows ABI case where we need to call __chkstk.
- // Function prologue is responsible for adjusting the stack pointer.
- BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), X86::EAX)
- .addImm(NumBytes);
- BuildMI(MBB, MBBI, DL, TII.get(X86::WINCALL64pcrel32))
- .addExternalSymbol("__chkstk")
- .addReg(StackPtr, RegState::Define | RegState::Implicit);
- emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
- } else if (NumBytes)
- emitSPUpdate(MBB, MBBI, StackPtr, -(int64_t)NumBytes, Is64Bit, TII);
-
- if ((NumBytes || PushedRegs) && needsFrameMoves) {
- // Mark end of stack pointer adjustment.
- MCSymbol *Label = MMI.getContext().CreateTempSymbol();
- BuildMI(MBB, MBBI, DL, TII.get(X86::PROLOG_LABEL)).addSym(Label);
-
- if (!HasFP && NumBytes) {
- // Define the current CFA rule to use the provided offset.
- if (StackSize) {
- MachineLocation SPDst(MachineLocation::VirtualFP);
- MachineLocation SPSrc(MachineLocation::VirtualFP,
- -StackSize + stackGrowth);
- Moves.push_back(MachineMove(Label, SPDst, SPSrc));
- } else {
- // FIXME: Verify & implement for FP
- MachineLocation SPDst(StackPtr);
- MachineLocation SPSrc(StackPtr, stackGrowth);
- Moves.push_back(MachineMove(Label, SPDst, SPSrc));
- }
- }
-
- // Emit DWARF info specifying the offsets of the callee-saved registers.
- if (PushedRegs)
- emitCalleeSavedFrameMoves(MF, Label, HasFP ? FramePtr : StackPtr);
- }
-}
-
-void X86RegisterInfo::emitEpilogue(MachineFunction &MF,
- MachineBasicBlock &MBB) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
- MachineBasicBlock::iterator MBBI = prior(MBB.end());
- unsigned RetOpcode = MBBI->getOpcode();
- DebugLoc DL = MBBI->getDebugLoc();
-
- switch (RetOpcode) {
- default:
- llvm_unreachable("Can only insert epilog into returning blocks");
- case X86::RET:
- case X86::RETI:
- case X86::TCRETURNdi:
- case X86::TCRETURNri:
- case X86::TCRETURNmi:
- case X86::TCRETURNdi64:
- case X86::TCRETURNri64:
- case X86::TCRETURNmi64:
- case X86::EH_RETURN:
- case X86::EH_RETURN64:
- break; // These are ok
- }
-
- // Get the number of bytes to allocate from the FrameInfo.
- uint64_t StackSize = MFI->getStackSize();
- uint64_t MaxAlign = MFI->getMaxAlignment();
- unsigned CSSize = X86FI->getCalleeSavedFrameSize();
- uint64_t NumBytes = 0;
-
- // If we're forcing a stack realignment we can't rely on just the frame
- // info, we need to know the ABI stack alignment as well in case we
- // have a call out. Otherwise just make sure we have some alignment - we'll
- // go with the minimum.
- if (ForceStackAlign) {
- if (MFI->hasCalls())
- MaxAlign = (StackAlign > MaxAlign) ? StackAlign : MaxAlign;
- else
- MaxAlign = MaxAlign ? MaxAlign : 4;
- }
-
- if (hasFP(MF)) {
- // Calculate required stack adjustment.
- uint64_t FrameSize = StackSize - SlotSize;
- if (needsStackRealignment(MF))
- FrameSize = (FrameSize + MaxAlign - 1)/MaxAlign*MaxAlign;
-
- NumBytes = FrameSize - CSSize;
-
- // Pop EBP.
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::POP64r : X86::POP32r), FramePtr);
- } else {
- NumBytes = StackSize - CSSize;
- }
-
- // Skip the callee-saved pop instructions.
- MachineBasicBlock::iterator LastCSPop = MBBI;
- while (MBBI != MBB.begin()) {
- MachineBasicBlock::iterator PI = prior(MBBI);
- unsigned Opc = PI->getOpcode();
-
- if (Opc != X86::POP32r && Opc != X86::POP64r &&
- !PI->getDesc().isTerminator())
- break;
-
- --MBBI;
- }
-
- DL = MBBI->getDebugLoc();
-
- // If there is an ADD32ri or SUB32ri of ESP immediately before this
- // instruction, merge the two instructions.
- if (NumBytes || MFI->hasVarSizedObjects())
- mergeSPUpdatesUp(MBB, MBBI, StackPtr, &NumBytes);
-
- // If dynamic alloca is used, then reset esp to point to the last callee-saved
- // slot before popping them off! Same applies for the case, when stack was
- // realigned.
- if (needsStackRealignment(MF)) {
- // We cannot use LEA here, because stack pointer was realigned. We need to
- // deallocate local frame back.
- if (CSSize) {
- emitSPUpdate(MBB, MBBI, StackPtr, NumBytes, Is64Bit, TII);
- MBBI = prior(LastCSPop);
- }
-
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr),
- StackPtr).addReg(FramePtr);
- } else if (MFI->hasVarSizedObjects()) {
- if (CSSize) {
- unsigned Opc = Is64Bit ? X86::LEA64r : X86::LEA32r;
- MachineInstr *MI =
- addRegOffset(BuildMI(MF, DL, TII.get(Opc), StackPtr),
- FramePtr, false, -CSSize);
- MBB.insert(MBBI, MI);
- } else {
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr), StackPtr)
- .addReg(FramePtr);
- }
- } else if (NumBytes) {
- // Adjust stack pointer back: ESP += numbytes.
- emitSPUpdate(MBB, MBBI, StackPtr, NumBytes, Is64Bit, TII);
- }
-
- // We're returning from function via eh_return.
- if (RetOpcode == X86::EH_RETURN || RetOpcode == X86::EH_RETURN64) {
- MBBI = prior(MBB.end());
- MachineOperand &DestAddr = MBBI->getOperand(0);
- assert(DestAddr.isReg() && "Offset should be in register!");
- BuildMI(MBB, MBBI, DL,
- TII.get(Is64Bit ? X86::MOV64rr : X86::MOV32rr),
- StackPtr).addReg(DestAddr.getReg());
- } else if (RetOpcode == X86::TCRETURNri || RetOpcode == X86::TCRETURNdi ||
- RetOpcode == X86::TCRETURNmi ||
- RetOpcode == X86::TCRETURNri64 || RetOpcode == X86::TCRETURNdi64 ||
- RetOpcode == X86::TCRETURNmi64) {
- bool isMem = RetOpcode == X86::TCRETURNmi || RetOpcode == X86::TCRETURNmi64;
- // Tail call return: adjust the stack pointer and jump to callee.
- MBBI = prior(MBB.end());
- MachineOperand &JumpTarget = MBBI->getOperand(0);
- MachineOperand &StackAdjust = MBBI->getOperand(isMem ? 5 : 1);
- assert(StackAdjust.isImm() && "Expecting immediate value.");
-
- // Adjust stack pointer.
- int StackAdj = StackAdjust.getImm();
- int MaxTCDelta = X86FI->getTCReturnAddrDelta();
- int Offset = 0;
- assert(MaxTCDelta <= 0 && "MaxTCDelta should never be positive");
-
- // Incoporate the retaddr area.
- Offset = StackAdj-MaxTCDelta;
- assert(Offset >= 0 && "Offset should never be negative");
-
- if (Offset) {
- // Check for possible merge with preceeding ADD instruction.
- Offset += mergeSPUpdates(MBB, MBBI, StackPtr, true);
- emitSPUpdate(MBB, MBBI, StackPtr, Offset, Is64Bit, TII);
- }
-
- // Jump to label or value in register.
- if (RetOpcode == X86::TCRETURNdi || RetOpcode == X86::TCRETURNdi64) {
- BuildMI(MBB, MBBI, DL, TII.get((RetOpcode == X86::TCRETURNdi)
- ? X86::TAILJMPd : X86::TAILJMPd64)).
- addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset(),
- JumpTarget.getTargetFlags());
- } else if (RetOpcode == X86::TCRETURNmi || RetOpcode == X86::TCRETURNmi64) {
- MachineInstrBuilder MIB =
- BuildMI(MBB, MBBI, DL, TII.get((RetOpcode == X86::TCRETURNmi)
- ? X86::TAILJMPm : X86::TAILJMPm64));
- for (unsigned i = 0; i != 5; ++i)
- MIB.addOperand(MBBI->getOperand(i));
- } else if (RetOpcode == X86::TCRETURNri64) {
- BuildMI(MBB, MBBI, DL, TII.get(X86::TAILJMPr64)).
- addReg(JumpTarget.getReg(), RegState::Kill);
- } else {
- BuildMI(MBB, MBBI, DL, TII.get(X86::TAILJMPr)).
- addReg(JumpTarget.getReg(), RegState::Kill);
- }
-
- MachineInstr *NewMI = prior(MBBI);
- for (unsigned i = 2, e = MBBI->getNumOperands(); i != e; ++i)
- NewMI->addOperand(MBBI->getOperand(i));
-
- // Delete the pseudo instruction TCRETURN.
- MBB.erase(MBBI);
- } else if ((RetOpcode == X86::RET || RetOpcode == X86::RETI) &&
- (X86FI->getTCReturnAddrDelta() < 0)) {
- // Add the return addr area delta back since we are not tail calling.
- int delta = -1*X86FI->getTCReturnAddrDelta();
- MBBI = prior(MBB.end());
-
- // Check for possible merge with preceeding ADD instruction.
- delta += mergeSPUpdates(MBB, MBBI, StackPtr, true);
- emitSPUpdate(MBB, MBBI, StackPtr, delta, Is64Bit, TII);
- }
-}
-
unsigned X86RegisterInfo::getRARegister() const {
return Is64Bit ? X86::RIP // Should have dwarf #16.
: X86::EIP; // Should have dwarf #8.
diff --git a/llvm/lib/Target/X86/X86RegisterInfo.h b/llvm/lib/Target/X86/X86RegisterInfo.h
index 527df05..0796191 100644
--- a/llvm/lib/Target/X86/X86RegisterInfo.h
+++ b/llvm/lib/Target/X86/X86RegisterInfo.h
@@ -132,14 +132,13 @@
void processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
RegScavenger *RS = NULL) const;
- void emitCalleeSavedFrameMoves(MachineFunction &MF, MCSymbol *Label,
- unsigned FramePtr) const;
- void emitPrologue(MachineFunction &MF) const;
- void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const;
-
// Debug information queries.
unsigned getRARegister() const;
unsigned getFrameRegister(const MachineFunction &MF) const;
+ unsigned getStackRegister() const { return StackPtr; }
+ // FIXME: Move to FrameInfok
+ unsigned getSlotSize() const { return SlotSize; }
+
int getFrameIndexOffset(const MachineFunction &MF, int FI) const;
void getInitialFrameState(std::vector<MachineMove> &Moves) const;
diff --git a/llvm/lib/Target/X86/X86TargetMachine.cpp b/llvm/lib/Target/X86/X86TargetMachine.cpp
index 4e435ee..4c01e60 100644
--- a/llvm/lib/Target/X86/X86TargetMachine.cpp
+++ b/llvm/lib/Target/X86/X86TargetMachine.cpp
@@ -119,10 +119,7 @@
const std::string &FS, bool is64Bit)
: LLVMTargetMachine(T, TT),
Subtarget(TT, FS, is64Bit),
- FrameInfo(TargetFrameInfo::StackGrowsDown,
- Subtarget.getStackAlignment(),
- (Subtarget.isTargetWin64() ? -40 :
- (Subtarget.is64Bit() ? -8 : -4))),
+ FrameInfo(Subtarget),
ELFWriterInfo(is64Bit, true) {
DefRelocModel = getRelocationModel();
diff --git a/llvm/lib/Target/X86/X86TargetMachine.h b/llvm/lib/Target/X86/X86TargetMachine.h
index 2b4b326..8ba7a71 100644
--- a/llvm/lib/Target/X86/X86TargetMachine.h
+++ b/llvm/lib/Target/X86/X86TargetMachine.h
@@ -14,16 +14,17 @@
#ifndef X86TARGETMACHINE_H
#define X86TARGETMACHINE_H
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetData.h"
-#include "llvm/Target/TargetFrameInfo.h"
#include "X86.h"
#include "X86ELFWriterInfo.h"
#include "X86InstrInfo.h"
-#include "X86JITInfo.h"
-#include "X86Subtarget.h"
#include "X86ISelLowering.h"
+#include "X86FrameInfo.h"
+#include "X86JITInfo.h"
#include "X86SelectionDAGInfo.h"
+#include "X86Subtarget.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetFrameInfo.h"
namespace llvm {
@@ -31,7 +32,7 @@
class X86TargetMachine : public LLVMTargetMachine {
X86Subtarget Subtarget;
- TargetFrameInfo FrameInfo;
+ X86FrameInfo FrameInfo;
X86ELFWriterInfo ELFWriterInfo;
Reloc::Model DefRelocModel; // Reloc model before it's overridden.