llvm-6502/lib/Target/X86/X86InstrInfo.h
Chris Lattner 548abfcbd6 Implement support for the bizarre 3DNow! encoding (which is unlike anything
else in X86), and add support for pavgusb.  This is apparently the
only instruction (other than movsx) that is preventing ffmpeg from building
with clang.

If someone else is interested in banging out the rest of the 3DNow! 
instructions, it should be quite easy now.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115466 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-03 18:08:05 +00:00

883 lines
36 KiB
C++

//===- X86InstrInfo.h - X86 Instruction 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 the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#ifndef X86INSTRUCTIONINFO_H
#define X86INSTRUCTIONINFO_H
#include "llvm/Target/TargetInstrInfo.h"
#include "X86.h"
#include "X86RegisterInfo.h"
#include "llvm/ADT/DenseMap.h"
namespace llvm {
class X86RegisterInfo;
class X86TargetMachine;
namespace X86 {
// Enums for memory operand decoding. Each memory operand is represented with
// a 5 operand sequence in the form:
// [BaseReg, ScaleAmt, IndexReg, Disp, Segment]
// These enums help decode this.
enum {
AddrBaseReg = 0,
AddrScaleAmt = 1,
AddrIndexReg = 2,
AddrDisp = 3,
/// AddrSegmentReg - The operand # of the segment in the memory operand.
AddrSegmentReg = 4,
/// AddrNumOperands - Total number of operands in a memory reference.
AddrNumOperands = 5
};
// X86 specific condition code. These correspond to X86_*_COND in
// X86InstrInfo.td. They must be kept in synch.
enum CondCode {
COND_A = 0,
COND_AE = 1,
COND_B = 2,
COND_BE = 3,
COND_E = 4,
COND_G = 5,
COND_GE = 6,
COND_L = 7,
COND_LE = 8,
COND_NE = 9,
COND_NO = 10,
COND_NP = 11,
COND_NS = 12,
COND_O = 13,
COND_P = 14,
COND_S = 15,
// Artificial condition codes. These are used by AnalyzeBranch
// to indicate a block terminated with two conditional branches to
// the same location. This occurs in code using FCMP_OEQ or FCMP_UNE,
// which can't be represented on x86 with a single condition. These
// are never used in MachineInstrs.
COND_NE_OR_P,
COND_NP_OR_E,
COND_INVALID
};
// Turn condition code into conditional branch opcode.
unsigned GetCondBranchFromCond(CondCode CC);
/// GetOppositeBranchCondition - Return the inverse of the specified cond,
/// e.g. turning COND_E to COND_NE.
CondCode GetOppositeBranchCondition(X86::CondCode CC);
}
/// X86II - This namespace holds all of the target specific flags that
/// instruction info tracks.
///
namespace X86II {
/// Target Operand Flag enum.
enum TOF {
//===------------------------------------------------------------------===//
// X86 Specific MachineOperand flags.
MO_NO_FLAG,
/// MO_GOT_ABSOLUTE_ADDRESS - On a symbol operand, this represents a
/// relocation of:
/// SYMBOL_LABEL + [. - PICBASELABEL]
MO_GOT_ABSOLUTE_ADDRESS,
/// MO_PIC_BASE_OFFSET - On a symbol operand this indicates that the
/// immediate should get the value of the symbol minus the PIC base label:
/// SYMBOL_LABEL - PICBASELABEL
MO_PIC_BASE_OFFSET,
/// MO_GOT - On a symbol operand this indicates that the immediate is the
/// offset to the GOT entry for the symbol name from the base of the GOT.
///
/// See the X86-64 ELF ABI supplement for more details.
/// SYMBOL_LABEL @GOT
MO_GOT,
/// MO_GOTOFF - On a symbol operand this indicates that the immediate is
/// the offset to the location of the symbol name from the base of the GOT.
///
/// See the X86-64 ELF ABI supplement for more details.
/// SYMBOL_LABEL @GOTOFF
MO_GOTOFF,
/// MO_GOTPCREL - On a symbol operand this indicates that the immediate is
/// offset to the GOT entry for the symbol name from the current code
/// location.
///
/// See the X86-64 ELF ABI supplement for more details.
/// SYMBOL_LABEL @GOTPCREL
MO_GOTPCREL,
/// MO_PLT - On a symbol operand this indicates that the immediate is
/// offset to the PLT entry of symbol name from the current code location.
///
/// See the X86-64 ELF ABI supplement for more details.
/// SYMBOL_LABEL @PLT
MO_PLT,
/// MO_TLSGD - On a symbol operand this indicates that the immediate is
/// some TLS offset.
///
/// See 'ELF Handling for Thread-Local Storage' for more details.
/// SYMBOL_LABEL @TLSGD
MO_TLSGD,
/// MO_GOTTPOFF - On a symbol operand this indicates that the immediate is
/// some TLS offset.
///
/// See 'ELF Handling for Thread-Local Storage' for more details.
/// SYMBOL_LABEL @GOTTPOFF
MO_GOTTPOFF,
/// MO_INDNTPOFF - On a symbol operand this indicates that the immediate is
/// some TLS offset.
///
/// See 'ELF Handling for Thread-Local Storage' for more details.
/// SYMBOL_LABEL @INDNTPOFF
MO_INDNTPOFF,
/// MO_TPOFF - On a symbol operand this indicates that the immediate is
/// some TLS offset.
///
/// See 'ELF Handling for Thread-Local Storage' for more details.
/// SYMBOL_LABEL @TPOFF
MO_TPOFF,
/// MO_NTPOFF - On a symbol operand this indicates that the immediate is
/// some TLS offset.
///
/// See 'ELF Handling for Thread-Local Storage' for more details.
/// SYMBOL_LABEL @NTPOFF
MO_NTPOFF,
/// MO_DLLIMPORT - On a symbol operand "FOO", this indicates that the
/// reference is actually to the "__imp_FOO" symbol. This is used for
/// dllimport linkage on windows.
MO_DLLIMPORT,
/// MO_DARWIN_STUB - On a symbol operand "FOO", this indicates that the
/// reference is actually to the "FOO$stub" symbol. This is used for calls
/// and jumps to external functions on Tiger and before.
MO_DARWIN_STUB,
/// MO_DARWIN_NONLAZY - On a symbol operand "FOO", this indicates that the
/// reference is actually to the "FOO$non_lazy_ptr" symbol, which is a
/// non-PIC-base-relative reference to a non-hidden dyld lazy pointer stub.
MO_DARWIN_NONLAZY,
/// MO_DARWIN_NONLAZY_PIC_BASE - On a symbol operand "FOO", this indicates
/// that the reference is actually to "FOO$non_lazy_ptr - PICBASE", which is
/// a PIC-base-relative reference to a non-hidden dyld lazy pointer stub.
MO_DARWIN_NONLAZY_PIC_BASE,
/// MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE - On a symbol operand "FOO", this
/// indicates that the reference is actually to "FOO$non_lazy_ptr -PICBASE",
/// which is a PIC-base-relative reference to a hidden dyld lazy pointer
/// stub.
MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE,
/// MO_TLVP - On a symbol operand this indicates that the immediate is
/// some TLS offset.
///
/// This is the TLS offset for the Darwin TLS mechanism.
MO_TLVP,
/// MO_TLVP_PIC_BASE - On a symbol operand this indicates that the immediate
/// is some TLS offset from the picbase.
///
/// This is the 32-bit TLS offset for Darwin TLS in PIC mode.
MO_TLVP_PIC_BASE
};
}
/// isGlobalStubReference - Return true if the specified TargetFlag operand is
/// a reference to a stub for a global, not the global itself.
inline static bool isGlobalStubReference(unsigned char TargetFlag) {
switch (TargetFlag) {
case X86II::MO_DLLIMPORT: // dllimport stub.
case X86II::MO_GOTPCREL: // rip-relative GOT reference.
case X86II::MO_GOT: // normal GOT reference.
case X86II::MO_DARWIN_NONLAZY_PIC_BASE: // Normal $non_lazy_ptr ref.
case X86II::MO_DARWIN_NONLAZY: // Normal $non_lazy_ptr ref.
case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE: // Hidden $non_lazy_ptr ref.
return true;
default:
return false;
}
}
/// isGlobalRelativeToPICBase - Return true if the specified global value
/// reference is relative to a 32-bit PIC base (X86ISD::GlobalBaseReg). If this
/// is true, the addressing mode has the PIC base register added in (e.g. EBX).
inline static bool isGlobalRelativeToPICBase(unsigned char TargetFlag) {
switch (TargetFlag) {
case X86II::MO_GOTOFF: // isPICStyleGOT: local global.
case X86II::MO_GOT: // isPICStyleGOT: other global.
case X86II::MO_PIC_BASE_OFFSET: // Darwin local global.
case X86II::MO_DARWIN_NONLAZY_PIC_BASE: // Darwin/32 external global.
case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE: // Darwin/32 hidden global.
case X86II::MO_TLVP: // ??? Pretty sure..
return true;
default:
return false;
}
}
/// X86II - This namespace holds all of the target specific flags that
/// instruction info tracks.
///
namespace X86II {
enum {
//===------------------------------------------------------------------===//
// Instruction encodings. These are the standard/most common forms for X86
// instructions.
//
// PseudoFrm - This represents an instruction that is a pseudo instruction
// or one that has not been implemented yet. It is illegal to code generate
// it, but tolerated for intermediate implementation stages.
Pseudo = 0,
/// Raw - This form is for instructions that don't have any operands, so
/// they are just a fixed opcode value, like 'leave'.
RawFrm = 1,
/// AddRegFrm - This form is used for instructions like 'push r32' that have
/// their one register operand added to their opcode.
AddRegFrm = 2,
/// MRMDestReg - This form is used for instructions that use the Mod/RM byte
/// to specify a destination, which in this case is a register.
///
MRMDestReg = 3,
/// MRMDestMem - This form is used for instructions that use the Mod/RM byte
/// to specify a destination, which in this case is memory.
///
MRMDestMem = 4,
/// MRMSrcReg - This form is used for instructions that use the Mod/RM byte
/// to specify a source, which in this case is a register.
///
MRMSrcReg = 5,
/// MRMSrcMem - This form is used for instructions that use the Mod/RM byte
/// to specify a source, which in this case is memory.
///
MRMSrcMem = 6,
/// MRM[0-7][rm] - These forms are used to represent instructions that use
/// a Mod/RM byte, and use the middle field to hold extended opcode
/// information. In the intel manual these are represented as /0, /1, ...
///
// First, instructions that operate on a register r/m operand...
MRM0r = 16, MRM1r = 17, MRM2r = 18, MRM3r = 19, // Format /0 /1 /2 /3
MRM4r = 20, MRM5r = 21, MRM6r = 22, MRM7r = 23, // Format /4 /5 /6 /7
// Next, instructions that operate on a memory r/m operand...
MRM0m = 24, MRM1m = 25, MRM2m = 26, MRM3m = 27, // Format /0 /1 /2 /3
MRM4m = 28, MRM5m = 29, MRM6m = 30, MRM7m = 31, // Format /4 /5 /6 /7
// MRMInitReg - This form is used for instructions whose source and
// destinations are the same register.
MRMInitReg = 32,
//// MRM_C1 - A mod/rm byte of exactly 0xC1.
MRM_C1 = 33,
MRM_C2 = 34,
MRM_C3 = 35,
MRM_C4 = 36,
MRM_C8 = 37,
MRM_C9 = 38,
MRM_E8 = 39,
MRM_F0 = 40,
MRM_F8 = 41,
MRM_F9 = 42,
/// RawFrmImm8 - This is used for the ENTER instruction, which has two
/// immediates, the first of which is a 16-bit immediate (specified by
/// the imm encoding) and the second is a 8-bit fixed value.
RawFrmImm8 = 43,
/// RawFrmImm16 - This is used for CALL FAR instructions, which have two
/// immediates, the first of which is a 16 or 32-bit immediate (specified by
/// the imm encoding) and the second is a 16-bit fixed value. In the AMD
/// manual, this operand is described as pntr16:32 and pntr16:16
RawFrmImm16 = 44,
FormMask = 63,
//===------------------------------------------------------------------===//
// Actual flags...
// OpSize - Set if this instruction requires an operand size prefix (0x66),
// which most often indicates that the instruction operates on 16 bit data
// instead of 32 bit data.
OpSize = 1 << 6,
// AsSize - Set if this instruction requires an operand size prefix (0x67),
// which most often indicates that the instruction address 16 bit address
// instead of 32 bit address (or 32 bit address in 64 bit mode).
AdSize = 1 << 7,
//===------------------------------------------------------------------===//
// Op0Mask - There are several prefix bytes that are used to form two byte
// opcodes. These are currently 0x0F, 0xF3, and 0xD8-0xDF. This mask is
// used to obtain the setting of this field. If no bits in this field is
// set, there is no prefix byte for obtaining a multibyte opcode.
//
Op0Shift = 8,
Op0Mask = 0xF << Op0Shift,
// TB - TwoByte - Set if this instruction has a two byte opcode, which
// starts with a 0x0F byte before the real opcode.
TB = 1 << Op0Shift,
// REP - The 0xF3 prefix byte indicating repetition of the following
// instruction.
REP = 2 << Op0Shift,
// D8-DF - These escape opcodes are used by the floating point unit. These
// values must remain sequential.
D8 = 3 << Op0Shift, D9 = 4 << Op0Shift,
DA = 5 << Op0Shift, DB = 6 << Op0Shift,
DC = 7 << Op0Shift, DD = 8 << Op0Shift,
DE = 9 << Op0Shift, DF = 10 << Op0Shift,
// XS, XD - These prefix codes are for single and double precision scalar
// floating point operations performed in the SSE registers.
XD = 11 << Op0Shift, XS = 12 << Op0Shift,
// T8, TA - Prefix after the 0x0F prefix.
T8 = 13 << Op0Shift, TA = 14 << Op0Shift,
// TF - Prefix before and after 0x0F
TF = 15 << Op0Shift,
//===------------------------------------------------------------------===//
// REX_W - REX prefixes are instruction prefixes used in 64-bit mode.
// They are used to specify GPRs and SSE registers, 64-bit operand size,
// etc. We only cares about REX.W and REX.R bits and only the former is
// statically determined.
//
REXShift = 12,
REX_W = 1 << REXShift,
//===------------------------------------------------------------------===//
// This three-bit field describes the size of an immediate operand. Zero is
// unused so that we can tell if we forgot to set a value.
ImmShift = 13,
ImmMask = 7 << ImmShift,
Imm8 = 1 << ImmShift,
Imm8PCRel = 2 << ImmShift,
Imm16 = 3 << ImmShift,
Imm16PCRel = 4 << ImmShift,
Imm32 = 5 << ImmShift,
Imm32PCRel = 6 << ImmShift,
Imm64 = 7 << ImmShift,
//===------------------------------------------------------------------===//
// FP Instruction Classification... Zero is non-fp instruction.
// FPTypeMask - Mask for all of the FP types...
FPTypeShift = 16,
FPTypeMask = 7 << FPTypeShift,
// NotFP - The default, set for instructions that do not use FP registers.
NotFP = 0 << FPTypeShift,
// ZeroArgFP - 0 arg FP instruction which implicitly pushes ST(0), f.e. fld0
ZeroArgFP = 1 << FPTypeShift,
// OneArgFP - 1 arg FP instructions which implicitly read ST(0), such as fst
OneArgFP = 2 << FPTypeShift,
// OneArgFPRW - 1 arg FP instruction which implicitly read ST(0) and write a
// result back to ST(0). For example, fcos, fsqrt, etc.
//
OneArgFPRW = 3 << FPTypeShift,
// TwoArgFP - 2 arg FP instructions which implicitly read ST(0), and an
// explicit argument, storing the result to either ST(0) or the implicit
// argument. For example: fadd, fsub, fmul, etc...
TwoArgFP = 4 << FPTypeShift,
// CompareFP - 2 arg FP instructions which implicitly read ST(0) and an
// explicit argument, but have no destination. Example: fucom, fucomi, ...
CompareFP = 5 << FPTypeShift,
// CondMovFP - "2 operand" floating point conditional move instructions.
CondMovFP = 6 << FPTypeShift,
// SpecialFP - Special instruction forms. Dispatch by opcode explicitly.
SpecialFP = 7 << FPTypeShift,
// Lock prefix
LOCKShift = 19,
LOCK = 1 << LOCKShift,
// Segment override prefixes. Currently we just need ability to address
// stuff in gs and fs segments.
SegOvrShift = 20,
SegOvrMask = 3 << SegOvrShift,
FS = 1 << SegOvrShift,
GS = 2 << SegOvrShift,
// Execution domain for SSE instructions in bits 22, 23.
// 0 in bits 22-23 means normal, non-SSE instruction.
SSEDomainShift = 22,
OpcodeShift = 24,
OpcodeMask = 0xFF << OpcodeShift,
//===------------------------------------------------------------------===//
/// VEX - The opcode prefix used by AVX instructions
VEX = 1U << 0,
/// VEX_W - Has a opcode specific functionality, but is used in the same
/// way as REX_W is for regular SSE instructions.
VEX_W = 1U << 1,
/// VEX_4V - Used to specify an additional AVX/SSE register. Several 2
/// address instructions in SSE are represented as 3 address ones in AVX
/// and the additional register is encoded in VEX_VVVV prefix.
VEX_4V = 1U << 2,
/// VEX_I8IMM - Specifies that the last register used in a AVX instruction,
/// must be encoded in the i8 immediate field. This usually happens in
/// instructions with 4 operands.
VEX_I8IMM = 1U << 3,
/// VEX_L - Stands for a bit in the VEX opcode prefix meaning the current
/// instruction uses 256-bit wide registers. This is usually auto detected
/// if a VR256 register is used, but some AVX instructions also have this
/// field marked when using a f256 memory references.
VEX_L = 1U << 4,
/// Has3DNow0F0FOpcode - This flag indicates that the instruction uses the
/// wacky 0x0F 0x0F prefix for 3DNow! instructions. The manual documents
/// this as having a 0x0F prefix with a 0x0F opcode, and each instruction
/// storing a classifier in the imm8 field. To simplify our implementation,
/// we handle this by storeing the classifier in the opcode field and using
/// this flag to indicate that the encoder should do the wacky 3DNow! thing.
Has3DNow0F0FOpcode = 1U << 5
};
// getBaseOpcodeFor - This function returns the "base" X86 opcode for the
// specified machine instruction.
//
static inline unsigned char getBaseOpcodeFor(uint64_t TSFlags) {
return TSFlags >> X86II::OpcodeShift;
}
static inline bool hasImm(uint64_t TSFlags) {
return (TSFlags & X86II::ImmMask) != 0;
}
/// getSizeOfImm - Decode the "size of immediate" field from the TSFlags field
/// of the specified instruction.
static inline unsigned getSizeOfImm(uint64_t TSFlags) {
switch (TSFlags & X86II::ImmMask) {
default: assert(0 && "Unknown immediate size");
case X86II::Imm8:
case X86II::Imm8PCRel: return 1;
case X86II::Imm16:
case X86II::Imm16PCRel: return 2;
case X86II::Imm32:
case X86II::Imm32PCRel: return 4;
case X86II::Imm64: return 8;
}
}
/// isImmPCRel - Return true if the immediate of the specified instruction's
/// TSFlags indicates that it is pc relative.
static inline unsigned isImmPCRel(uint64_t TSFlags) {
switch (TSFlags & X86II::ImmMask) {
default: assert(0 && "Unknown immediate size");
case X86II::Imm8PCRel:
case X86II::Imm16PCRel:
case X86II::Imm32PCRel:
return true;
case X86II::Imm8:
case X86II::Imm16:
case X86II::Imm32:
case X86II::Imm64:
return false;
}
}
/// getMemoryOperandNo - The function returns the MCInst operand # for the
/// first field of the memory operand. If the instruction doesn't have a
/// memory operand, this returns -1.
///
/// Note that this ignores tied operands. If there is a tied register which
/// is duplicated in the MCInst (e.g. "EAX = addl EAX, [mem]") it is only
/// counted as one operand.
///
static inline int getMemoryOperandNo(uint64_t TSFlags) {
switch (TSFlags & X86II::FormMask) {
case X86II::MRMInitReg: assert(0 && "FIXME: Remove this form");
default: assert(0 && "Unknown FormMask value in getMemoryOperandNo!");
case X86II::Pseudo:
case X86II::RawFrm:
case X86II::AddRegFrm:
case X86II::MRMDestReg:
case X86II::MRMSrcReg:
case X86II::RawFrmImm8:
case X86II::RawFrmImm16:
return -1;
case X86II::MRMDestMem:
return 0;
case X86II::MRMSrcMem: {
bool HasVEX_4V = (TSFlags >> 32) & X86II::VEX_4V;
unsigned FirstMemOp = 1;
if (HasVEX_4V)
++FirstMemOp;// Skip the register source (which is encoded in VEX_VVVV).
// FIXME: Maybe lea should have its own form? This is a horrible hack.
//if (Opcode == X86::LEA64r || Opcode == X86::LEA64_32r ||
// Opcode == X86::LEA16r || Opcode == X86::LEA32r)
return FirstMemOp;
}
case X86II::MRM0r: case X86II::MRM1r:
case X86II::MRM2r: case X86II::MRM3r:
case X86II::MRM4r: case X86II::MRM5r:
case X86II::MRM6r: case X86II::MRM7r:
return -1;
case X86II::MRM0m: case X86II::MRM1m:
case X86II::MRM2m: case X86II::MRM3m:
case X86II::MRM4m: case X86II::MRM5m:
case X86II::MRM6m: case X86II::MRM7m:
return 0;
case X86II::MRM_C1:
case X86II::MRM_C2:
case X86II::MRM_C3:
case X86II::MRM_C4:
case X86II::MRM_C8:
case X86II::MRM_C9:
case X86II::MRM_E8:
case X86II::MRM_F0:
case X86II::MRM_F8:
case X86II::MRM_F9:
return -1;
}
}
}
inline static bool isScale(const MachineOperand &MO) {
return MO.isImm() &&
(MO.getImm() == 1 || MO.getImm() == 2 ||
MO.getImm() == 4 || MO.getImm() == 8);
}
inline static bool isLeaMem(const MachineInstr *MI, unsigned Op) {
if (MI->getOperand(Op).isFI()) return true;
return Op+4 <= MI->getNumOperands() &&
MI->getOperand(Op ).isReg() && isScale(MI->getOperand(Op+1)) &&
MI->getOperand(Op+2).isReg() &&
(MI->getOperand(Op+3).isImm() ||
MI->getOperand(Op+3).isGlobal() ||
MI->getOperand(Op+3).isCPI() ||
MI->getOperand(Op+3).isJTI());
}
inline static bool isMem(const MachineInstr *MI, unsigned Op) {
if (MI->getOperand(Op).isFI()) return true;
return Op+5 <= MI->getNumOperands() &&
MI->getOperand(Op+4).isReg() &&
isLeaMem(MI, Op);
}
class X86InstrInfo : public TargetInstrInfoImpl {
X86TargetMachine &TM;
const X86RegisterInfo RI;
/// RegOp2MemOpTable2Addr, RegOp2MemOpTable0, RegOp2MemOpTable1,
/// RegOp2MemOpTable2 - Load / store folding opcode maps.
///
DenseMap<unsigned*, std::pair<unsigned,unsigned> > RegOp2MemOpTable2Addr;
DenseMap<unsigned*, std::pair<unsigned,unsigned> > RegOp2MemOpTable0;
DenseMap<unsigned*, std::pair<unsigned,unsigned> > RegOp2MemOpTable1;
DenseMap<unsigned*, std::pair<unsigned,unsigned> > RegOp2MemOpTable2;
/// MemOp2RegOpTable - Load / store unfolding opcode map.
///
DenseMap<unsigned*, std::pair<unsigned, unsigned> > MemOp2RegOpTable;
public:
explicit X86InstrInfo(X86TargetMachine &tm);
/// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As
/// such, whenever a client has an instance of instruction info, it should
/// always be able to get register info as well (through this method).
///
virtual const X86RegisterInfo &getRegisterInfo() const { return RI; }
/// isCoalescableExtInstr - Return true if the instruction is a "coalescable"
/// extension instruction. That is, it's like a copy where it's legal for the
/// source to overlap the destination. e.g. X86::MOVSX64rr32. If this returns
/// true, then it's expected the pre-extension value is available as a subreg
/// of the result register. This also returns the sub-register index in
/// SubIdx.
virtual bool isCoalescableExtInstr(const MachineInstr &MI,
unsigned &SrcReg, unsigned &DstReg,
unsigned &SubIdx) const;
unsigned isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const;
/// isLoadFromStackSlotPostFE - Check for post-frame ptr elimination
/// stack locations as well. This uses a heuristic so it isn't
/// reliable for correctness.
unsigned isLoadFromStackSlotPostFE(const MachineInstr *MI,
int &FrameIndex) const;
/// hasLoadFromStackSlot - If the specified machine instruction has
/// a load from a stack slot, return true along with the FrameIndex
/// of the loaded stack slot and the machine mem operand containing
/// the reference. If not, return false. Unlike
/// isLoadFromStackSlot, this returns true for any instructions that
/// loads from the stack. This is a hint only and may not catch all
/// cases.
bool hasLoadFromStackSlot(const MachineInstr *MI,
const MachineMemOperand *&MMO,
int &FrameIndex) const;
unsigned isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const;
/// isStoreToStackSlotPostFE - Check for post-frame ptr elimination
/// stack locations as well. This uses a heuristic so it isn't
/// reliable for correctness.
unsigned isStoreToStackSlotPostFE(const MachineInstr *MI,
int &FrameIndex) const;
/// hasStoreToStackSlot - If the specified machine instruction has a
/// store to a stack slot, return true along with the FrameIndex of
/// the loaded stack slot and the machine mem operand containing the
/// reference. If not, return false. Unlike isStoreToStackSlot,
/// this returns true for any instructions that loads from the
/// stack. This is a hint only and may not catch all cases.
bool hasStoreToStackSlot(const MachineInstr *MI,
const MachineMemOperand *&MMO,
int &FrameIndex) const;
bool isReallyTriviallyReMaterializable(const MachineInstr *MI,
AliasAnalysis *AA) const;
void reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SubIdx,
const MachineInstr *Orig,
const TargetRegisterInfo &TRI) const;
/// convertToThreeAddress - This method must be implemented by targets that
/// set the M_CONVERTIBLE_TO_3_ADDR flag. When this flag is set, the target
/// may be able to convert a two-address instruction into a true
/// three-address instruction on demand. This allows the X86 target (for
/// example) to convert ADD and SHL instructions into LEA instructions if they
/// would require register copies due to two-addressness.
///
/// This method returns a null pointer if the transformation cannot be
/// performed, otherwise it returns the new instruction.
///
virtual MachineInstr *convertToThreeAddress(MachineFunction::iterator &MFI,
MachineBasicBlock::iterator &MBBI,
LiveVariables *LV) const;
/// commuteInstruction - We have a few instructions that must be hacked on to
/// commute them.
///
virtual MachineInstr *commuteInstruction(MachineInstr *MI, bool NewMI) const;
// Branch analysis.
virtual bool isUnpredicatedTerminator(const MachineInstr* MI) const;
virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const;
virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const;
virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond,
DebugLoc DL) const;
virtual void copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI, DebugLoc DL,
unsigned DestReg, unsigned SrcReg,
bool KillSrc) const;
virtual void storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, bool isKill, int FrameIndex,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const;
virtual void storeRegToAddr(MachineFunction &MF, unsigned SrcReg, bool isKill,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
MachineInstr::mmo_iterator MMOBegin,
MachineInstr::mmo_iterator MMOEnd,
SmallVectorImpl<MachineInstr*> &NewMIs) const;
virtual void loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIndex,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const;
virtual void loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
MachineInstr::mmo_iterator MMOBegin,
MachineInstr::mmo_iterator MMOEnd,
SmallVectorImpl<MachineInstr*> &NewMIs) const;
virtual bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI,
const TargetRegisterInfo *TRI) const;
virtual bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI,
const TargetRegisterInfo *TRI) const;
virtual
MachineInstr *emitFrameIndexDebugValue(MachineFunction &MF,
int FrameIx, uint64_t Offset,
const MDNode *MDPtr,
DebugLoc DL) const;
/// foldMemoryOperand - If this target supports it, fold a load or store of
/// the specified stack slot into the specified machine instruction for the
/// specified operand(s). If this is possible, the target should perform the
/// folding and return true, otherwise it should return false. If it folds
/// the instruction, it is likely that the MachineInstruction the iterator
/// references has been changed.
virtual MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
MachineInstr* MI,
const SmallVectorImpl<unsigned> &Ops,
int FrameIndex) const;
/// foldMemoryOperand - Same as the previous version except it allows folding
/// of any load and store from / to any address, not just from a specific
/// stack slot.
virtual MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
MachineInstr* MI,
const SmallVectorImpl<unsigned> &Ops,
MachineInstr* LoadMI) const;
/// canFoldMemoryOperand - Returns true if the specified load / store is
/// folding is possible.
virtual bool canFoldMemoryOperand(const MachineInstr*,
const SmallVectorImpl<unsigned> &) const;
/// unfoldMemoryOperand - Separate a single instruction which folded a load or
/// a store or a load and a store into two or more instruction. If this is
/// possible, returns true as well as the new instructions by reference.
virtual bool unfoldMemoryOperand(MachineFunction &MF, MachineInstr *MI,
unsigned Reg, bool UnfoldLoad, bool UnfoldStore,
SmallVectorImpl<MachineInstr*> &NewMIs) const;
virtual bool unfoldMemoryOperand(SelectionDAG &DAG, SDNode *N,
SmallVectorImpl<SDNode*> &NewNodes) const;
/// getOpcodeAfterMemoryUnfold - Returns the opcode of the would be new
/// instruction after load / store are unfolded from an instruction of the
/// specified opcode. It returns zero if the specified unfolding is not
/// possible. If LoadRegIndex is non-null, it is filled in with the operand
/// index of the operand which will hold the register holding the loaded
/// value.
virtual unsigned getOpcodeAfterMemoryUnfold(unsigned Opc,
bool UnfoldLoad, bool UnfoldStore,
unsigned *LoadRegIndex = 0) const;
/// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler
/// to determine if two loads are loading from the same base address. It
/// should only return true if the base pointers are the same and the
/// only differences between the two addresses are the offset. It also returns
/// the offsets by reference.
virtual bool areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2,
int64_t &Offset1, int64_t &Offset2) const;
/// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
/// determine (in conjuction with areLoadsFromSameBasePtr) if two loads should
/// be scheduled togther. On some targets if two loads are loading from
/// addresses in the same cache line, it's better if they are scheduled
/// together. This function takes two integers that represent the load offsets
/// from the common base address. It returns true if it decides it's desirable
/// to schedule the two loads together. "NumLoads" is the number of loads that
/// have already been scheduled after Load1.
virtual bool shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2,
int64_t Offset1, int64_t Offset2,
unsigned NumLoads) const;
virtual void getNoopForMachoTarget(MCInst &NopInst) const;
virtual
bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const;
/// isSafeToMoveRegClassDefs - Return true if it's safe to move a machine
/// instruction that defines the specified register class.
bool isSafeToMoveRegClassDefs(const TargetRegisterClass *RC) const;
static bool isX86_64NonExtLowByteReg(unsigned reg) {
return (reg == X86::SPL || reg == X86::BPL ||
reg == X86::SIL || reg == X86::DIL);
}
static bool isX86_64ExtendedReg(const MachineOperand &MO) {
if (!MO.isReg()) return false;
return isX86_64ExtendedReg(MO.getReg());
}
/// isX86_64ExtendedReg - Is the MachineOperand a x86-64 extended (r8 or
/// higher) register? e.g. r8, xmm8, xmm13, etc.
static bool isX86_64ExtendedReg(unsigned RegNo);
/// getGlobalBaseReg - Return a virtual register initialized with the
/// the global base register value. Output instructions required to
/// initialize the register in the function entry block, if necessary.
///
unsigned getGlobalBaseReg(MachineFunction *MF) const;
/// GetSSEDomain - Return the SSE execution domain of MI as the first element,
/// and a bitmask of possible arguments to SetSSEDomain ase the second.
std::pair<uint16_t, uint16_t> GetSSEDomain(const MachineInstr *MI) const;
/// SetSSEDomain - Set the SSEDomain of MI.
void SetSSEDomain(MachineInstr *MI, unsigned Domain) const;
MachineInstr* foldMemoryOperandImpl(MachineFunction &MF,
MachineInstr* MI,
unsigned OpNum,
const SmallVectorImpl<MachineOperand> &MOs,
unsigned Size, unsigned Alignment) const;
private:
MachineInstr * convertToThreeAddressWithLEA(unsigned MIOpc,
MachineFunction::iterator &MFI,
MachineBasicBlock::iterator &MBBI,
LiveVariables *LV) const;
/// isFrameOperand - Return true and the FrameIndex if the specified
/// operand and follow operands form a reference to the stack frame.
bool isFrameOperand(const MachineInstr *MI, unsigned int Op,
int &FrameIndex) const;
};
} // End llvm namespace
#endif