forked from OSchip/llvm-project
650 lines
22 KiB
C++
650 lines
22 KiB
C++
//===-- X86RegisterInfo.cpp - X86 Register Information --------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file contains the X86 implementation of the TargetRegisterInfo class.
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// This file is responsible for the frame pointer elimination optimization
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// on X86.
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//
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//===----------------------------------------------------------------------===//
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#include "X86RegisterInfo.h"
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#include "X86FrameLowering.h"
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#include "X86InstrBuilder.h"
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#include "X86MachineFunctionInfo.h"
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#include "X86Subtarget.h"
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#include "X86TargetMachine.h"
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#include "llvm/ADT/BitVector.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineFunctionPass.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/MachineModuleInfo.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/Function.h"
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#include "llvm/IR/Type.h"
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#include "llvm/MC/MCAsmInfo.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Target/TargetFrameLowering.h"
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#include "llvm/Target/TargetInstrInfo.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetOptions.h"
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using namespace llvm;
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#define GET_REGINFO_TARGET_DESC
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#include "X86GenRegisterInfo.inc"
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static cl::opt<bool>
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EnableBasePointer("x86-use-base-pointer", cl::Hidden, cl::init(true),
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cl::desc("Enable use of a base pointer for complex stack frames"));
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X86RegisterInfo::X86RegisterInfo(const Triple &TT)
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: X86GenRegisterInfo((TT.isArch64Bit() ? X86::RIP : X86::EIP),
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X86_MC::getDwarfRegFlavour(TT, false),
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X86_MC::getDwarfRegFlavour(TT, true),
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(TT.isArch64Bit() ? X86::RIP : X86::EIP)) {
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X86_MC::initLLVMToSEHAndCVRegMapping(this);
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// Cache some information.
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Is64Bit = TT.isArch64Bit();
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IsWin64 = Is64Bit && TT.isOSWindows();
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// Use a callee-saved register as the base pointer. These registers must
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// not conflict with any ABI requirements. For example, in 32-bit mode PIC
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// requires GOT in the EBX register before function calls via PLT GOT pointer.
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if (Is64Bit) {
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SlotSize = 8;
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// This matches the simplified 32-bit pointer code in the data layout
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// computation.
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// FIXME: Should use the data layout?
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bool Use64BitReg = TT.getEnvironment() != Triple::GNUX32;
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StackPtr = Use64BitReg ? X86::RSP : X86::ESP;
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FramePtr = Use64BitReg ? X86::RBP : X86::EBP;
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BasePtr = Use64BitReg ? X86::RBX : X86::EBX;
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} else {
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SlotSize = 4;
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StackPtr = X86::ESP;
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FramePtr = X86::EBP;
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BasePtr = X86::ESI;
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}
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}
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bool
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X86RegisterInfo::trackLivenessAfterRegAlloc(const MachineFunction &MF) const {
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// ExeDepsFixer and PostRAScheduler require liveness.
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return true;
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}
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int
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X86RegisterInfo::getSEHRegNum(unsigned i) const {
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return getEncodingValue(i);
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}
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const TargetRegisterClass *
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X86RegisterInfo::getSubClassWithSubReg(const TargetRegisterClass *RC,
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unsigned Idx) const {
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// The sub_8bit sub-register index is more constrained in 32-bit mode.
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// It behaves just like the sub_8bit_hi index.
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if (!Is64Bit && Idx == X86::sub_8bit)
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Idx = X86::sub_8bit_hi;
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// Forward to TableGen's default version.
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return X86GenRegisterInfo::getSubClassWithSubReg(RC, Idx);
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}
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const TargetRegisterClass *
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X86RegisterInfo::getMatchingSuperRegClass(const TargetRegisterClass *A,
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const TargetRegisterClass *B,
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unsigned SubIdx) const {
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// The sub_8bit sub-register index is more constrained in 32-bit mode.
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if (!Is64Bit && SubIdx == X86::sub_8bit) {
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A = X86GenRegisterInfo::getSubClassWithSubReg(A, X86::sub_8bit_hi);
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if (!A)
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return nullptr;
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}
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return X86GenRegisterInfo::getMatchingSuperRegClass(A, B, SubIdx);
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}
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const TargetRegisterClass *
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X86RegisterInfo::getLargestLegalSuperClass(const TargetRegisterClass *RC,
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const MachineFunction &MF) const {
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// Don't allow super-classes of GR8_NOREX. This class is only used after
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// extracting sub_8bit_hi sub-registers. The H sub-registers cannot be copied
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// to the full GR8 register class in 64-bit mode, so we cannot allow the
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// reigster class inflation.
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//
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// The GR8_NOREX class is always used in a way that won't be constrained to a
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// sub-class, so sub-classes like GR8_ABCD_L are allowed to expand to the
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// full GR8 class.
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if (RC == &X86::GR8_NOREXRegClass)
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return RC;
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const TargetRegisterClass *Super = RC;
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TargetRegisterClass::sc_iterator I = RC->getSuperClasses();
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do {
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switch (Super->getID()) {
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case X86::GR8RegClassID:
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case X86::GR16RegClassID:
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case X86::GR32RegClassID:
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case X86::GR64RegClassID:
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case X86::FR32RegClassID:
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case X86::FR64RegClassID:
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case X86::RFP32RegClassID:
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case X86::RFP64RegClassID:
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case X86::RFP80RegClassID:
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case X86::VR128RegClassID:
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case X86::VR256RegClassID:
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// Don't return a super-class that would shrink the spill size.
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// That can happen with the vector and float classes.
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if (Super->getSize() == RC->getSize())
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return Super;
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}
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Super = *I++;
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} while (Super);
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return RC;
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}
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const TargetRegisterClass *
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X86RegisterInfo::getPointerRegClass(const MachineFunction &MF,
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unsigned Kind) const {
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const X86Subtarget &Subtarget = MF.getSubtarget<X86Subtarget>();
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switch (Kind) {
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default: llvm_unreachable("Unexpected Kind in getPointerRegClass!");
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case 0: // Normal GPRs.
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if (Subtarget.isTarget64BitLP64())
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return &X86::GR64RegClass;
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return &X86::GR32RegClass;
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case 1: // Normal GPRs except the stack pointer (for encoding reasons).
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if (Subtarget.isTarget64BitLP64())
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return &X86::GR64_NOSPRegClass;
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return &X86::GR32_NOSPRegClass;
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case 2: // NOREX GPRs.
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if (Subtarget.isTarget64BitLP64())
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return &X86::GR64_NOREXRegClass;
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return &X86::GR32_NOREXRegClass;
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case 3: // NOREX GPRs except the stack pointer (for encoding reasons).
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if (Subtarget.isTarget64BitLP64())
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return &X86::GR64_NOREX_NOSPRegClass;
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return &X86::GR32_NOREX_NOSPRegClass;
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case 4: // Available for tailcall (not callee-saved GPRs).
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return getGPRsForTailCall(MF);
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}
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}
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const TargetRegisterClass *
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X86RegisterInfo::getGPRsForTailCall(const MachineFunction &MF) const {
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const Function *F = MF.getFunction();
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if (IsWin64 || (F && F->getCallingConv() == CallingConv::X86_64_Win64))
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return &X86::GR64_TCW64RegClass;
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else if (Is64Bit)
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return &X86::GR64_TCRegClass;
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bool hasHipeCC = (F ? F->getCallingConv() == CallingConv::HiPE : false);
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if (hasHipeCC)
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return &X86::GR32RegClass;
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return &X86::GR32_TCRegClass;
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}
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const TargetRegisterClass *
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X86RegisterInfo::getCrossCopyRegClass(const TargetRegisterClass *RC) const {
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if (RC == &X86::CCRRegClass) {
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if (Is64Bit)
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return &X86::GR64RegClass;
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else
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return &X86::GR32RegClass;
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}
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return RC;
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}
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unsigned
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X86RegisterInfo::getRegPressureLimit(const TargetRegisterClass *RC,
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MachineFunction &MF) const {
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const X86FrameLowering *TFI = getFrameLowering(MF);
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unsigned FPDiff = TFI->hasFP(MF) ? 1 : 0;
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switch (RC->getID()) {
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default:
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return 0;
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case X86::GR32RegClassID:
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return 4 - FPDiff;
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case X86::GR64RegClassID:
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return 12 - FPDiff;
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case X86::VR128RegClassID:
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return Is64Bit ? 10 : 4;
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case X86::VR64RegClassID:
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return 4;
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}
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}
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const MCPhysReg *
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X86RegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
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const X86Subtarget &Subtarget = MF->getSubtarget<X86Subtarget>();
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bool HasSSE = Subtarget.hasSSE1();
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bool HasAVX = Subtarget.hasAVX();
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bool HasAVX512 = Subtarget.hasAVX512();
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bool CallsEHReturn = MF->getMMI().callsEHReturn();
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assert(MF && "MachineFunction required");
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switch (MF->getFunction()->getCallingConv()) {
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case CallingConv::GHC:
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case CallingConv::HiPE:
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return CSR_NoRegs_SaveList;
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case CallingConv::AnyReg:
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if (HasAVX)
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return CSR_64_AllRegs_AVX_SaveList;
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return CSR_64_AllRegs_SaveList;
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case CallingConv::PreserveMost:
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return CSR_64_RT_MostRegs_SaveList;
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case CallingConv::PreserveAll:
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if (HasAVX)
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return CSR_64_RT_AllRegs_AVX_SaveList;
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return CSR_64_RT_AllRegs_SaveList;
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case CallingConv::CXX_FAST_TLS:
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if (Is64Bit)
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return MF->getInfo<X86MachineFunctionInfo>()->isSplitCSR() ?
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CSR_64_CXX_TLS_Darwin_PE_SaveList : CSR_64_TLS_Darwin_SaveList;
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break;
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case CallingConv::Intel_OCL_BI: {
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if (HasAVX512 && IsWin64)
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return CSR_Win64_Intel_OCL_BI_AVX512_SaveList;
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if (HasAVX512 && Is64Bit)
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return CSR_64_Intel_OCL_BI_AVX512_SaveList;
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if (HasAVX && IsWin64)
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return CSR_Win64_Intel_OCL_BI_AVX_SaveList;
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if (HasAVX && Is64Bit)
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return CSR_64_Intel_OCL_BI_AVX_SaveList;
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if (!HasAVX && !IsWin64 && Is64Bit)
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return CSR_64_Intel_OCL_BI_SaveList;
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break;
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}
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case CallingConv::HHVM:
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return CSR_64_HHVM_SaveList;
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case CallingConv::Cold:
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if (Is64Bit)
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return CSR_64_MostRegs_SaveList;
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break;
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case CallingConv::X86_64_Win64:
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return CSR_Win64_SaveList;
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case CallingConv::X86_64_SysV:
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if (CallsEHReturn)
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return CSR_64EHRet_SaveList;
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return CSR_64_SaveList;
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case CallingConv::X86_INTR:
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if (Is64Bit) {
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if (HasAVX)
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return CSR_64_AllRegs_AVX_SaveList;
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else
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return CSR_64_AllRegs_SaveList;
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} else {
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if (HasSSE)
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return CSR_32_AllRegs_SSE_SaveList;
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else
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return CSR_32_AllRegs_SaveList;
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}
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default:
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break;
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}
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if (Is64Bit) {
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if (IsWin64)
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return CSR_Win64_SaveList;
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if (CallsEHReturn)
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return CSR_64EHRet_SaveList;
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return CSR_64_SaveList;
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}
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if (CallsEHReturn)
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return CSR_32EHRet_SaveList;
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return CSR_32_SaveList;
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}
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const MCPhysReg *X86RegisterInfo::getCalleeSavedRegsViaCopy(
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const MachineFunction *MF) const {
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assert(MF && "Invalid MachineFunction pointer.");
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if (MF->getFunction()->getCallingConv() == CallingConv::CXX_FAST_TLS &&
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MF->getInfo<X86MachineFunctionInfo>()->isSplitCSR())
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return CSR_64_CXX_TLS_Darwin_ViaCopy_SaveList;
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return nullptr;
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}
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const uint32_t *
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X86RegisterInfo::getCallPreservedMask(const MachineFunction &MF,
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CallingConv::ID CC) const {
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const X86Subtarget &Subtarget = MF.getSubtarget<X86Subtarget>();
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bool HasSSE = Subtarget.hasSSE1();
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bool HasAVX = Subtarget.hasAVX();
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bool HasAVX512 = Subtarget.hasAVX512();
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switch (CC) {
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case CallingConv::GHC:
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case CallingConv::HiPE:
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return CSR_NoRegs_RegMask;
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case CallingConv::AnyReg:
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if (HasAVX)
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return CSR_64_AllRegs_AVX_RegMask;
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return CSR_64_AllRegs_RegMask;
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case CallingConv::PreserveMost:
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return CSR_64_RT_MostRegs_RegMask;
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case CallingConv::PreserveAll:
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if (HasAVX)
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return CSR_64_RT_AllRegs_AVX_RegMask;
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return CSR_64_RT_AllRegs_RegMask;
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case CallingConv::CXX_FAST_TLS:
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if (Is64Bit)
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return CSR_64_TLS_Darwin_RegMask;
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break;
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case CallingConv::Intel_OCL_BI: {
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if (HasAVX512 && IsWin64)
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return CSR_Win64_Intel_OCL_BI_AVX512_RegMask;
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if (HasAVX512 && Is64Bit)
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return CSR_64_Intel_OCL_BI_AVX512_RegMask;
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if (HasAVX && IsWin64)
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return CSR_Win64_Intel_OCL_BI_AVX_RegMask;
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if (HasAVX && Is64Bit)
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return CSR_64_Intel_OCL_BI_AVX_RegMask;
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if (!HasAVX && !IsWin64 && Is64Bit)
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return CSR_64_Intel_OCL_BI_RegMask;
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break;
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}
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case CallingConv::HHVM:
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return CSR_64_HHVM_RegMask;
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case CallingConv::Cold:
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if (Is64Bit)
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return CSR_64_MostRegs_RegMask;
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break;
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case CallingConv::X86_64_Win64:
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return CSR_Win64_RegMask;
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case CallingConv::X86_64_SysV:
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return CSR_64_RegMask;
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case CallingConv::X86_INTR:
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if (Is64Bit) {
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if (HasAVX)
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return CSR_64_AllRegs_AVX_RegMask;
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else
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return CSR_64_AllRegs_RegMask;
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} else {
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if (HasSSE)
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return CSR_32_AllRegs_SSE_RegMask;
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else
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return CSR_32_AllRegs_RegMask;
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}
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default:
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break;
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}
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// Unlike getCalleeSavedRegs(), we don't have MMI so we can't check
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// callsEHReturn().
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if (Is64Bit) {
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if (IsWin64)
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return CSR_Win64_RegMask;
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return CSR_64_RegMask;
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}
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return CSR_32_RegMask;
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}
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const uint32_t*
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X86RegisterInfo::getNoPreservedMask() const {
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return CSR_NoRegs_RegMask;
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}
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const uint32_t *X86RegisterInfo::getDarwinTLSCallPreservedMask() const {
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return CSR_64_TLS_Darwin_RegMask;
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}
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BitVector X86RegisterInfo::getReservedRegs(const MachineFunction &MF) const {
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BitVector Reserved(getNumRegs());
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const X86FrameLowering *TFI = getFrameLowering(MF);
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// Set the stack-pointer register and its aliases as reserved.
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for (MCSubRegIterator I(X86::RSP, this, /*IncludeSelf=*/true); I.isValid();
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++I)
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Reserved.set(*I);
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// Set the instruction pointer register and its aliases as reserved.
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for (MCSubRegIterator I(X86::RIP, this, /*IncludeSelf=*/true); I.isValid();
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++I)
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Reserved.set(*I);
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// Set the frame-pointer register and its aliases as reserved if needed.
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if (TFI->hasFP(MF)) {
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for (MCSubRegIterator I(X86::RBP, this, /*IncludeSelf=*/true); I.isValid();
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++I)
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Reserved.set(*I);
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}
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// Set the base-pointer register and its aliases as reserved if needed.
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if (hasBasePointer(MF)) {
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CallingConv::ID CC = MF.getFunction()->getCallingConv();
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const uint32_t *RegMask = getCallPreservedMask(MF, CC);
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if (MachineOperand::clobbersPhysReg(RegMask, getBaseRegister()))
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report_fatal_error(
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"Stack realignment in presence of dynamic allocas is not supported with"
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"this calling convention.");
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unsigned BasePtr = getX86SubSuperRegister(getBaseRegister(), 64);
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for (MCSubRegIterator I(BasePtr, this, /*IncludeSelf=*/true);
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I.isValid(); ++I)
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Reserved.set(*I);
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}
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// Mark the segment registers as reserved.
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Reserved.set(X86::CS);
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Reserved.set(X86::SS);
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Reserved.set(X86::DS);
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Reserved.set(X86::ES);
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Reserved.set(X86::FS);
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Reserved.set(X86::GS);
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// Mark the floating point stack registers as reserved.
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for (unsigned n = 0; n != 8; ++n)
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Reserved.set(X86::ST0 + n);
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// Reserve the registers that only exist in 64-bit mode.
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if (!Is64Bit) {
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// These 8-bit registers are part of the x86-64 extension even though their
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// super-registers are old 32-bits.
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Reserved.set(X86::SIL);
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Reserved.set(X86::DIL);
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Reserved.set(X86::BPL);
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Reserved.set(X86::SPL);
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for (unsigned n = 0; n != 8; ++n) {
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// R8, R9, ...
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for (MCRegAliasIterator AI(X86::R8 + n, this, true); AI.isValid(); ++AI)
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Reserved.set(*AI);
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// XMM8, XMM9, ...
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for (MCRegAliasIterator AI(X86::XMM8 + n, this, true); AI.isValid(); ++AI)
|
|
Reserved.set(*AI);
|
|
}
|
|
}
|
|
if (!Is64Bit || !MF.getSubtarget<X86Subtarget>().hasAVX512()) {
|
|
for (unsigned n = 16; n != 32; ++n) {
|
|
for (MCRegAliasIterator AI(X86::XMM0 + n, this, true); AI.isValid(); ++AI)
|
|
Reserved.set(*AI);
|
|
}
|
|
}
|
|
|
|
return Reserved;
|
|
}
|
|
|
|
void X86RegisterInfo::adjustStackMapLiveOutMask(uint32_t *Mask) const {
|
|
// Check if the EFLAGS register is marked as live-out. This shouldn't happen,
|
|
// because the calling convention defines the EFLAGS register as NOT
|
|
// preserved.
|
|
//
|
|
// Unfortunatelly the EFLAGS show up as live-out after branch folding. Adding
|
|
// an assert to track this and clear the register afterwards to avoid
|
|
// unnecessary crashes during release builds.
|
|
assert(!(Mask[X86::EFLAGS / 32] & (1U << (X86::EFLAGS % 32))) &&
|
|
"EFLAGS are not live-out from a patchpoint.");
|
|
|
|
// Also clean other registers that don't need preserving (IP).
|
|
for (auto Reg : {X86::EFLAGS, X86::RIP, X86::EIP, X86::IP})
|
|
Mask[Reg / 32] &= ~(1U << (Reg % 32));
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Stack Frame Processing methods
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
static bool CantUseSP(const MachineFrameInfo *MFI) {
|
|
return MFI->hasVarSizedObjects() || MFI->hasOpaqueSPAdjustment();
|
|
}
|
|
|
|
bool X86RegisterInfo::hasBasePointer(const MachineFunction &MF) const {
|
|
const MachineFrameInfo *MFI = MF.getFrameInfo();
|
|
|
|
if (!EnableBasePointer)
|
|
return false;
|
|
|
|
// When we need stack realignment, we can't address the stack from the frame
|
|
// pointer. When we have dynamic allocas or stack-adjusting inline asm, we
|
|
// can't address variables from the stack pointer. MS inline asm can
|
|
// reference locals while also adjusting the stack pointer. When we can't
|
|
// use both the SP and the FP, we need a separate base pointer register.
|
|
bool CantUseFP = needsStackRealignment(MF);
|
|
return CantUseFP && CantUseSP(MFI);
|
|
}
|
|
|
|
bool X86RegisterInfo::canRealignStack(const MachineFunction &MF) const {
|
|
if (!TargetRegisterInfo::canRealignStack(MF))
|
|
return false;
|
|
|
|
const MachineFrameInfo *MFI = MF.getFrameInfo();
|
|
const MachineRegisterInfo *MRI = &MF.getRegInfo();
|
|
|
|
// Stack realignment requires a frame pointer. If we already started
|
|
// register allocation with frame pointer elimination, it is too late now.
|
|
if (!MRI->canReserveReg(FramePtr))
|
|
return false;
|
|
|
|
// If a base pointer is necessary. Check that it isn't too late to reserve
|
|
// it.
|
|
if (CantUseSP(MFI))
|
|
return MRI->canReserveReg(BasePtr);
|
|
return true;
|
|
}
|
|
|
|
bool X86RegisterInfo::hasReservedSpillSlot(const MachineFunction &MF,
|
|
unsigned Reg, int &FrameIdx) const {
|
|
// Since X86 defines assignCalleeSavedSpillSlots which always return true
|
|
// this function neither used nor tested.
|
|
llvm_unreachable("Unused function on X86. Otherwise need a test case.");
|
|
}
|
|
|
|
void
|
|
X86RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
|
|
int SPAdj, unsigned FIOperandNum,
|
|
RegScavenger *RS) const {
|
|
MachineInstr &MI = *II;
|
|
MachineFunction &MF = *MI.getParent()->getParent();
|
|
const X86FrameLowering *TFI = getFrameLowering(MF);
|
|
int FrameIndex = MI.getOperand(FIOperandNum).getIndex();
|
|
unsigned BasePtr;
|
|
|
|
unsigned Opc = MI.getOpcode();
|
|
bool AfterFPPop = Opc == X86::TAILJMPm64 || Opc == X86::TAILJMPm ||
|
|
Opc == X86::TCRETURNmi || Opc == X86::TCRETURNmi64;
|
|
|
|
if (hasBasePointer(MF))
|
|
BasePtr = (FrameIndex < 0 ? FramePtr : getBaseRegister());
|
|
else if (needsStackRealignment(MF))
|
|
BasePtr = (FrameIndex < 0 ? FramePtr : StackPtr);
|
|
else if (AfterFPPop)
|
|
BasePtr = StackPtr;
|
|
else
|
|
BasePtr = (TFI->hasFP(MF) ? FramePtr : StackPtr);
|
|
|
|
// LOCAL_ESCAPE uses a single offset, with no register. It only works in the
|
|
// simple FP case, and doesn't work with stack realignment. On 32-bit, the
|
|
// offset is from the traditional base pointer location. On 64-bit, the
|
|
// offset is from the SP at the end of the prologue, not the FP location. This
|
|
// matches the behavior of llvm.frameaddress.
|
|
unsigned IgnoredFrameReg;
|
|
if (Opc == TargetOpcode::LOCAL_ESCAPE) {
|
|
MachineOperand &FI = MI.getOperand(FIOperandNum);
|
|
int Offset;
|
|
Offset = TFI->getFrameIndexReference(MF, FrameIndex, IgnoredFrameReg);
|
|
FI.ChangeToImmediate(Offset);
|
|
return;
|
|
}
|
|
|
|
// For LEA64_32r when BasePtr is 32-bits (X32) we can use full-size 64-bit
|
|
// register as source operand, semantic is the same and destination is
|
|
// 32-bits. It saves one byte per lea in code since 0x67 prefix is avoided.
|
|
if (Opc == X86::LEA64_32r && X86::GR32RegClass.contains(BasePtr))
|
|
BasePtr = getX86SubSuperRegister(BasePtr, 64);
|
|
|
|
// This must be part of a four operand memory reference. Replace the
|
|
// FrameIndex with base register with EBP. Add an offset to the offset.
|
|
MI.getOperand(FIOperandNum).ChangeToRegister(BasePtr, false);
|
|
|
|
// Now add the frame object offset to the offset from EBP.
|
|
int FIOffset;
|
|
if (AfterFPPop) {
|
|
// Tail call jmp happens after FP is popped.
|
|
const MachineFrameInfo *MFI = MF.getFrameInfo();
|
|
FIOffset = MFI->getObjectOffset(FrameIndex) - TFI->getOffsetOfLocalArea();
|
|
} else
|
|
FIOffset = TFI->getFrameIndexReference(MF, FrameIndex, IgnoredFrameReg);
|
|
|
|
if (BasePtr == StackPtr)
|
|
FIOffset += SPAdj;
|
|
|
|
// The frame index format for stackmaps and patchpoints is different from the
|
|
// X86 format. It only has a FI and an offset.
|
|
if (Opc == TargetOpcode::STACKMAP || Opc == TargetOpcode::PATCHPOINT) {
|
|
assert(BasePtr == FramePtr && "Expected the FP as base register");
|
|
int64_t Offset = MI.getOperand(FIOperandNum + 1).getImm() + FIOffset;
|
|
MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
|
|
return;
|
|
}
|
|
|
|
if (MI.getOperand(FIOperandNum+3).isImm()) {
|
|
// Offset is a 32-bit integer.
|
|
int Imm = (int)(MI.getOperand(FIOperandNum + 3).getImm());
|
|
int Offset = FIOffset + Imm;
|
|
assert((!Is64Bit || isInt<32>((long long)FIOffset + Imm)) &&
|
|
"Requesting 64-bit offset in 32-bit immediate!");
|
|
MI.getOperand(FIOperandNum + 3).ChangeToImmediate(Offset);
|
|
} else {
|
|
// Offset is symbolic. This is extremely rare.
|
|
uint64_t Offset = FIOffset +
|
|
(uint64_t)MI.getOperand(FIOperandNum+3).getOffset();
|
|
MI.getOperand(FIOperandNum + 3).setOffset(Offset);
|
|
}
|
|
}
|
|
|
|
unsigned X86RegisterInfo::getFrameRegister(const MachineFunction &MF) const {
|
|
const X86FrameLowering *TFI = getFrameLowering(MF);
|
|
return TFI->hasFP(MF) ? FramePtr : StackPtr;
|
|
}
|
|
|
|
unsigned
|
|
X86RegisterInfo::getPtrSizedFrameRegister(const MachineFunction &MF) const {
|
|
const X86Subtarget &Subtarget = MF.getSubtarget<X86Subtarget>();
|
|
unsigned FrameReg = getFrameRegister(MF);
|
|
if (Subtarget.isTarget64BitILP32())
|
|
FrameReg = getX86SubSuperRegister(FrameReg, 32);
|
|
return FrameReg;
|
|
}
|
|
|
|
unsigned llvm::get512BitSuperRegister(unsigned Reg) {
|
|
if (Reg >= X86::XMM0 && Reg <= X86::XMM31)
|
|
return X86::ZMM0 + (Reg - X86::XMM0);
|
|
if (Reg >= X86::YMM0 && Reg <= X86::YMM31)
|
|
return X86::ZMM0 + (Reg - X86::YMM0);
|
|
if (Reg >= X86::ZMM0 && Reg <= X86::ZMM31)
|
|
return Reg;
|
|
llvm_unreachable("Unexpected SIMD register");
|
|
}
|