1 //===- X86InstrInfo.h - X86 Instruction Information ------------*- C++ -*- ===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the X86 implementation of the TargetInstrInfo class.
12 //===----------------------------------------------------------------------===//
14 #ifndef X86INSTRUCTIONINFO_H
15 #define X86INSTRUCTIONINFO_H
17 #include "llvm/Target/TargetInstrInfo.h"
19 #include "X86RegisterInfo.h"
20 #include "llvm/ADT/DenseMap.h"
22 #define GET_INSTRINFO_HEADER
23 #include "X86GenInstrInfo.inc"
26 class X86RegisterInfo
;
27 class X86TargetMachine
;
30 // Enums for memory operand decoding. Each memory operand is represented with
31 // a 5 operand sequence in the form:
32 // [BaseReg, ScaleAmt, IndexReg, Disp, Segment]
33 // These enums help decode this.
40 /// AddrSegmentReg - The operand # of the segment in the memory operand.
43 /// AddrNumOperands - Total number of operands in a memory reference.
48 // X86 specific condition code. These correspond to X86_*_COND in
49 // X86InstrInfo.td. They must be kept in synch.
68 // Artificial condition codes. These are used by AnalyzeBranch
69 // to indicate a block terminated with two conditional branches to
70 // the same location. This occurs in code using FCMP_OEQ or FCMP_UNE,
71 // which can't be represented on x86 with a single condition. These
72 // are never used in MachineInstrs.
79 // Turn condition code into conditional branch opcode.
80 unsigned GetCondBranchFromCond(CondCode CC
);
82 /// GetOppositeBranchCondition - Return the inverse of the specified cond,
83 /// e.g. turning COND_E to COND_NE.
84 CondCode
GetOppositeBranchCondition(X86::CondCode CC
);
88 /// X86II - This namespace holds all of the target specific flags that
89 /// instruction info tracks.
92 /// Target Operand Flag enum.
94 //===------------------------------------------------------------------===//
95 // X86 Specific MachineOperand flags.
99 /// MO_GOT_ABSOLUTE_ADDRESS - On a symbol operand, this represents a
101 /// SYMBOL_LABEL + [. - PICBASELABEL]
102 MO_GOT_ABSOLUTE_ADDRESS
,
104 /// MO_PIC_BASE_OFFSET - On a symbol operand this indicates that the
105 /// immediate should get the value of the symbol minus the PIC base label:
106 /// SYMBOL_LABEL - PICBASELABEL
109 /// MO_GOT - On a symbol operand this indicates that the immediate is the
110 /// offset to the GOT entry for the symbol name from the base of the GOT.
112 /// See the X86-64 ELF ABI supplement for more details.
113 /// SYMBOL_LABEL @GOT
116 /// MO_GOTOFF - On a symbol operand this indicates that the immediate is
117 /// the offset to the location of the symbol name from the base of the GOT.
119 /// See the X86-64 ELF ABI supplement for more details.
120 /// SYMBOL_LABEL @GOTOFF
123 /// MO_GOTPCREL - On a symbol operand this indicates that the immediate is
124 /// offset to the GOT entry for the symbol name from the current code
127 /// See the X86-64 ELF ABI supplement for more details.
128 /// SYMBOL_LABEL @GOTPCREL
131 /// MO_PLT - On a symbol operand this indicates that the immediate is
132 /// offset to the PLT entry of symbol name from the current code location.
134 /// See the X86-64 ELF ABI supplement for more details.
135 /// SYMBOL_LABEL @PLT
138 /// MO_TLSGD - On a symbol operand this indicates that the immediate is
141 /// See 'ELF Handling for Thread-Local Storage' for more details.
142 /// SYMBOL_LABEL @TLSGD
145 /// MO_GOTTPOFF - On a symbol operand this indicates that the immediate is
148 /// See 'ELF Handling for Thread-Local Storage' for more details.
149 /// SYMBOL_LABEL @GOTTPOFF
152 /// MO_INDNTPOFF - On a symbol operand this indicates that the immediate is
155 /// See 'ELF Handling for Thread-Local Storage' for more details.
156 /// SYMBOL_LABEL @INDNTPOFF
159 /// MO_TPOFF - On a symbol operand this indicates that the immediate is
162 /// See 'ELF Handling for Thread-Local Storage' for more details.
163 /// SYMBOL_LABEL @TPOFF
166 /// MO_NTPOFF - On a symbol operand this indicates that the immediate is
169 /// See 'ELF Handling for Thread-Local Storage' for more details.
170 /// SYMBOL_LABEL @NTPOFF
173 /// MO_DLLIMPORT - On a symbol operand "FOO", this indicates that the
174 /// reference is actually to the "__imp_FOO" symbol. This is used for
175 /// dllimport linkage on windows.
178 /// MO_DARWIN_STUB - On a symbol operand "FOO", this indicates that the
179 /// reference is actually to the "FOO$stub" symbol. This is used for calls
180 /// and jumps to external functions on Tiger and earlier.
183 /// MO_DARWIN_NONLAZY - On a symbol operand "FOO", this indicates that the
184 /// reference is actually to the "FOO$non_lazy_ptr" symbol, which is a
185 /// non-PIC-base-relative reference to a non-hidden dyld lazy pointer stub.
188 /// MO_DARWIN_NONLAZY_PIC_BASE - On a symbol operand "FOO", this indicates
189 /// that the reference is actually to "FOO$non_lazy_ptr - PICBASE", which is
190 /// a PIC-base-relative reference to a non-hidden dyld lazy pointer stub.
191 MO_DARWIN_NONLAZY_PIC_BASE
,
193 /// MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE - On a symbol operand "FOO", this
194 /// indicates that the reference is actually to "FOO$non_lazy_ptr -PICBASE",
195 /// which is a PIC-base-relative reference to a hidden dyld lazy pointer
197 MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE
,
199 /// MO_TLVP - On a symbol operand this indicates that the immediate is
202 /// This is the TLS offset for the Darwin TLS mechanism.
205 /// MO_TLVP_PIC_BASE - On a symbol operand this indicates that the immediate
206 /// is some TLS offset from the picbase.
208 /// This is the 32-bit TLS offset for Darwin TLS in PIC mode.
213 /// isGlobalStubReference - Return true if the specified TargetFlag operand is
214 /// a reference to a stub for a global, not the global itself.
215 inline static bool isGlobalStubReference(unsigned char TargetFlag
) {
216 switch (TargetFlag
) {
217 case X86II::MO_DLLIMPORT
: // dllimport stub.
218 case X86II::MO_GOTPCREL
: // rip-relative GOT reference.
219 case X86II::MO_GOT
: // normal GOT reference.
220 case X86II::MO_DARWIN_NONLAZY_PIC_BASE
: // Normal $non_lazy_ptr ref.
221 case X86II::MO_DARWIN_NONLAZY
: // Normal $non_lazy_ptr ref.
222 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE
: // Hidden $non_lazy_ptr ref.
229 /// isGlobalRelativeToPICBase - Return true if the specified global value
230 /// reference is relative to a 32-bit PIC base (X86ISD::GlobalBaseReg). If this
231 /// is true, the addressing mode has the PIC base register added in (e.g. EBX).
232 inline static bool isGlobalRelativeToPICBase(unsigned char TargetFlag
) {
233 switch (TargetFlag
) {
234 case X86II::MO_GOTOFF
: // isPICStyleGOT: local global.
235 case X86II::MO_GOT
: // isPICStyleGOT: other global.
236 case X86II::MO_PIC_BASE_OFFSET
: // Darwin local global.
237 case X86II::MO_DARWIN_NONLAZY_PIC_BASE
: // Darwin/32 external global.
238 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE
: // Darwin/32 hidden global.
239 case X86II::MO_TLVP
: // ??? Pretty sure..
246 /// X86II - This namespace holds all of the target specific flags that
247 /// instruction info tracks.
251 //===------------------------------------------------------------------===//
252 // Instruction encodings. These are the standard/most common forms for X86
256 // PseudoFrm - This represents an instruction that is a pseudo instruction
257 // or one that has not been implemented yet. It is illegal to code generate
258 // it, but tolerated for intermediate implementation stages.
261 /// Raw - This form is for instructions that don't have any operands, so
262 /// they are just a fixed opcode value, like 'leave'.
265 /// AddRegFrm - This form is used for instructions like 'push r32' that have
266 /// their one register operand added to their opcode.
269 /// MRMDestReg - This form is used for instructions that use the Mod/RM byte
270 /// to specify a destination, which in this case is a register.
274 /// MRMDestMem - This form is used for instructions that use the Mod/RM byte
275 /// to specify a destination, which in this case is memory.
279 /// MRMSrcReg - This form is used for instructions that use the Mod/RM byte
280 /// to specify a source, which in this case is a register.
284 /// MRMSrcMem - This form is used for instructions that use the Mod/RM byte
285 /// to specify a source, which in this case is memory.
289 /// MRM[0-7][rm] - These forms are used to represent instructions that use
290 /// a Mod/RM byte, and use the middle field to hold extended opcode
291 /// information. In the intel manual these are represented as /0, /1, ...
294 // First, instructions that operate on a register r/m operand...
295 MRM0r
= 16, MRM1r
= 17, MRM2r
= 18, MRM3r
= 19, // Format /0 /1 /2 /3
296 MRM4r
= 20, MRM5r
= 21, MRM6r
= 22, MRM7r
= 23, // Format /4 /5 /6 /7
298 // Next, instructions that operate on a memory r/m operand...
299 MRM0m
= 24, MRM1m
= 25, MRM2m
= 26, MRM3m
= 27, // Format /0 /1 /2 /3
300 MRM4m
= 28, MRM5m
= 29, MRM6m
= 30, MRM7m
= 31, // Format /4 /5 /6 /7
302 // MRMInitReg - This form is used for instructions whose source and
303 // destinations are the same register.
306 //// MRM_C1 - A mod/rm byte of exactly 0xC1.
320 /// RawFrmImm8 - This is used for the ENTER instruction, which has two
321 /// immediates, the first of which is a 16-bit immediate (specified by
322 /// the imm encoding) and the second is a 8-bit fixed value.
325 /// RawFrmImm16 - This is used for CALL FAR instructions, which have two
326 /// immediates, the first of which is a 16 or 32-bit immediate (specified by
327 /// the imm encoding) and the second is a 16-bit fixed value. In the AMD
328 /// manual, this operand is described as pntr16:32 and pntr16:16
333 //===------------------------------------------------------------------===//
336 // OpSize - Set if this instruction requires an operand size prefix (0x66),
337 // which most often indicates that the instruction operates on 16 bit data
338 // instead of 32 bit data.
341 // AsSize - Set if this instruction requires an operand size prefix (0x67),
342 // which most often indicates that the instruction address 16 bit address
343 // instead of 32 bit address (or 32 bit address in 64 bit mode).
346 //===------------------------------------------------------------------===//
347 // Op0Mask - There are several prefix bytes that are used to form two byte
348 // opcodes. These are currently 0x0F, 0xF3, and 0xD8-0xDF. This mask is
349 // used to obtain the setting of this field. If no bits in this field is
350 // set, there is no prefix byte for obtaining a multibyte opcode.
353 Op0Mask
= 0x1F << Op0Shift
,
355 // TB - TwoByte - Set if this instruction has a two byte opcode, which
356 // starts with a 0x0F byte before the real opcode.
359 // REP - The 0xF3 prefix byte indicating repetition of the following
363 // D8-DF - These escape opcodes are used by the floating point unit. These
364 // values must remain sequential.
365 D8
= 3 << Op0Shift
, D9
= 4 << Op0Shift
,
366 DA
= 5 << Op0Shift
, DB
= 6 << Op0Shift
,
367 DC
= 7 << Op0Shift
, DD
= 8 << Op0Shift
,
368 DE
= 9 << Op0Shift
, DF
= 10 << Op0Shift
,
370 // XS, XD - These prefix codes are for single and double precision scalar
371 // floating point operations performed in the SSE registers.
372 XD
= 11 << Op0Shift
, XS
= 12 << Op0Shift
,
374 // T8, TA, A6, A7 - Prefix after the 0x0F prefix.
375 T8
= 13 << Op0Shift
, TA
= 14 << Op0Shift
,
376 A6
= 15 << Op0Shift
, A7
= 16 << Op0Shift
,
378 // TF - Prefix before and after 0x0F
381 //===------------------------------------------------------------------===//
382 // REX_W - REX prefixes are instruction prefixes used in 64-bit mode.
383 // They are used to specify GPRs and SSE registers, 64-bit operand size,
384 // etc. We only cares about REX.W and REX.R bits and only the former is
385 // statically determined.
387 REXShift
= Op0Shift
+ 5,
388 REX_W
= 1 << REXShift
,
390 //===------------------------------------------------------------------===//
391 // This three-bit field describes the size of an immediate operand. Zero is
392 // unused so that we can tell if we forgot to set a value.
393 ImmShift
= REXShift
+ 1,
394 ImmMask
= 7 << ImmShift
,
395 Imm8
= 1 << ImmShift
,
396 Imm8PCRel
= 2 << ImmShift
,
397 Imm16
= 3 << ImmShift
,
398 Imm16PCRel
= 4 << ImmShift
,
399 Imm32
= 5 << ImmShift
,
400 Imm32PCRel
= 6 << ImmShift
,
401 Imm64
= 7 << ImmShift
,
403 //===------------------------------------------------------------------===//
404 // FP Instruction Classification... Zero is non-fp instruction.
406 // FPTypeMask - Mask for all of the FP types...
407 FPTypeShift
= ImmShift
+ 3,
408 FPTypeMask
= 7 << FPTypeShift
,
410 // NotFP - The default, set for instructions that do not use FP registers.
411 NotFP
= 0 << FPTypeShift
,
413 // ZeroArgFP - 0 arg FP instruction which implicitly pushes ST(0), f.e. fld0
414 ZeroArgFP
= 1 << FPTypeShift
,
416 // OneArgFP - 1 arg FP instructions which implicitly read ST(0), such as fst
417 OneArgFP
= 2 << FPTypeShift
,
419 // OneArgFPRW - 1 arg FP instruction which implicitly read ST(0) and write a
420 // result back to ST(0). For example, fcos, fsqrt, etc.
422 OneArgFPRW
= 3 << FPTypeShift
,
424 // TwoArgFP - 2 arg FP instructions which implicitly read ST(0), and an
425 // explicit argument, storing the result to either ST(0) or the implicit
426 // argument. For example: fadd, fsub, fmul, etc...
427 TwoArgFP
= 4 << FPTypeShift
,
429 // CompareFP - 2 arg FP instructions which implicitly read ST(0) and an
430 // explicit argument, but have no destination. Example: fucom, fucomi, ...
431 CompareFP
= 5 << FPTypeShift
,
433 // CondMovFP - "2 operand" floating point conditional move instructions.
434 CondMovFP
= 6 << FPTypeShift
,
436 // SpecialFP - Special instruction forms. Dispatch by opcode explicitly.
437 SpecialFP
= 7 << FPTypeShift
,
440 LOCKShift
= FPTypeShift
+ 3,
441 LOCK
= 1 << LOCKShift
,
443 // Segment override prefixes. Currently we just need ability to address
444 // stuff in gs and fs segments.
445 SegOvrShift
= LOCKShift
+ 1,
446 SegOvrMask
= 3 << SegOvrShift
,
447 FS
= 1 << SegOvrShift
,
448 GS
= 2 << SegOvrShift
,
450 // Execution domain for SSE instructions in bits 23, 24.
451 // 0 in bits 23-24 means normal, non-SSE instruction.
452 SSEDomainShift
= SegOvrShift
+ 2,
454 OpcodeShift
= SSEDomainShift
+ 2,
456 //===------------------------------------------------------------------===//
457 /// VEX - The opcode prefix used by AVX instructions
458 VEXShift
= OpcodeShift
+ 8,
461 /// VEX_W - Has a opcode specific functionality, but is used in the same
462 /// way as REX_W is for regular SSE instructions.
465 /// VEX_4V - Used to specify an additional AVX/SSE register. Several 2
466 /// address instructions in SSE are represented as 3 address ones in AVX
467 /// and the additional register is encoded in VEX_VVVV prefix.
470 /// VEX_I8IMM - Specifies that the last register used in a AVX instruction,
471 /// must be encoded in the i8 immediate field. This usually happens in
472 /// instructions with 4 operands.
475 /// VEX_L - Stands for a bit in the VEX opcode prefix meaning the current
476 /// instruction uses 256-bit wide registers. This is usually auto detected
477 /// if a VR256 register is used, but some AVX instructions also have this
478 /// field marked when using a f256 memory references.
481 /// Has3DNow0F0FOpcode - This flag indicates that the instruction uses the
482 /// wacky 0x0F 0x0F prefix for 3DNow! instructions. The manual documents
483 /// this as having a 0x0F prefix with a 0x0F opcode, and each instruction
484 /// storing a classifier in the imm8 field. To simplify our implementation,
485 /// we handle this by storeing the classifier in the opcode field and using
486 /// this flag to indicate that the encoder should do the wacky 3DNow! thing.
487 Has3DNow0F0FOpcode
= 1U << 5
490 // getBaseOpcodeFor - This function returns the "base" X86 opcode for the
491 // specified machine instruction.
493 static inline unsigned char getBaseOpcodeFor(uint64_t TSFlags
) {
494 return TSFlags
>> X86II::OpcodeShift
;
497 static inline bool hasImm(uint64_t TSFlags
) {
498 return (TSFlags
& X86II::ImmMask
) != 0;
501 /// getSizeOfImm - Decode the "size of immediate" field from the TSFlags field
502 /// of the specified instruction.
503 static inline unsigned getSizeOfImm(uint64_t TSFlags
) {
504 switch (TSFlags
& X86II::ImmMask
) {
505 default: assert(0 && "Unknown immediate size");
507 case X86II::Imm8PCRel
: return 1;
509 case X86II::Imm16PCRel
: return 2;
511 case X86II::Imm32PCRel
: return 4;
512 case X86II::Imm64
: return 8;
516 /// isImmPCRel - Return true if the immediate of the specified instruction's
517 /// TSFlags indicates that it is pc relative.
518 static inline unsigned isImmPCRel(uint64_t TSFlags
) {
519 switch (TSFlags
& X86II::ImmMask
) {
520 default: assert(0 && "Unknown immediate size");
521 case X86II::Imm8PCRel
:
522 case X86II::Imm16PCRel
:
523 case X86II::Imm32PCRel
:
533 /// getMemoryOperandNo - The function returns the MCInst operand # for the
534 /// first field of the memory operand. If the instruction doesn't have a
535 /// memory operand, this returns -1.
537 /// Note that this ignores tied operands. If there is a tied register which
538 /// is duplicated in the MCInst (e.g. "EAX = addl EAX, [mem]") it is only
539 /// counted as one operand.
541 static inline int getMemoryOperandNo(uint64_t TSFlags
) {
542 switch (TSFlags
& X86II::FormMask
) {
543 case X86II::MRMInitReg
: assert(0 && "FIXME: Remove this form");
544 default: assert(0 && "Unknown FormMask value in getMemoryOperandNo!");
547 case X86II::AddRegFrm
:
548 case X86II::MRMDestReg
:
549 case X86II::MRMSrcReg
:
550 case X86II::RawFrmImm8
:
551 case X86II::RawFrmImm16
:
553 case X86II::MRMDestMem
:
555 case X86II::MRMSrcMem
: {
556 bool HasVEX_4V
= (TSFlags
>> X86II::VEXShift
) & X86II::VEX_4V
;
557 unsigned FirstMemOp
= 1;
559 ++FirstMemOp
;// Skip the register source (which is encoded in VEX_VVVV).
561 // FIXME: Maybe lea should have its own form? This is a horrible hack.
562 //if (Opcode == X86::LEA64r || Opcode == X86::LEA64_32r ||
563 // Opcode == X86::LEA16r || Opcode == X86::LEA32r)
566 case X86II::MRM0r
: case X86II::MRM1r
:
567 case X86II::MRM2r
: case X86II::MRM3r
:
568 case X86II::MRM4r
: case X86II::MRM5r
:
569 case X86II::MRM6r
: case X86II::MRM7r
:
571 case X86II::MRM0m
: case X86II::MRM1m
:
572 case X86II::MRM2m
: case X86II::MRM3m
:
573 case X86II::MRM4m
: case X86II::MRM5m
:
574 case X86II::MRM6m
: case X86II::MRM7m
:
593 inline static bool isScale(const MachineOperand
&MO
) {
595 (MO
.getImm() == 1 || MO
.getImm() == 2 ||
596 MO
.getImm() == 4 || MO
.getImm() == 8);
599 inline static bool isLeaMem(const MachineInstr
*MI
, unsigned Op
) {
600 if (MI
->getOperand(Op
).isFI()) return true;
601 return Op
+4 <= MI
->getNumOperands() &&
602 MI
->getOperand(Op
).isReg() && isScale(MI
->getOperand(Op
+1)) &&
603 MI
->getOperand(Op
+2).isReg() &&
604 (MI
->getOperand(Op
+3).isImm() ||
605 MI
->getOperand(Op
+3).isGlobal() ||
606 MI
->getOperand(Op
+3).isCPI() ||
607 MI
->getOperand(Op
+3).isJTI());
610 inline static bool isMem(const MachineInstr
*MI
, unsigned Op
) {
611 if (MI
->getOperand(Op
).isFI()) return true;
612 return Op
+5 <= MI
->getNumOperands() &&
613 MI
->getOperand(Op
+4).isReg() &&
617 class X86InstrInfo
: public X86GenInstrInfo
{
618 X86TargetMachine
&TM
;
619 const X86RegisterInfo RI
;
621 /// RegOp2MemOpTable2Addr, RegOp2MemOpTable0, RegOp2MemOpTable1,
622 /// RegOp2MemOpTable2 - Load / store folding opcode maps.
624 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable2Addr
;
625 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable0
;
626 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable1
;
627 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable2
;
629 /// MemOp2RegOpTable - Load / store unfolding opcode map.
631 DenseMap
<unsigned, std::pair
<unsigned, unsigned> > MemOp2RegOpTable
;
634 explicit X86InstrInfo(X86TargetMachine
&tm
);
636 /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As
637 /// such, whenever a client has an instance of instruction info, it should
638 /// always be able to get register info as well (through this method).
640 virtual const X86RegisterInfo
&getRegisterInfo() const { return RI
; }
642 /// isCoalescableExtInstr - Return true if the instruction is a "coalescable"
643 /// extension instruction. That is, it's like a copy where it's legal for the
644 /// source to overlap the destination. e.g. X86::MOVSX64rr32. If this returns
645 /// true, then it's expected the pre-extension value is available as a subreg
646 /// of the result register. This also returns the sub-register index in
648 virtual bool isCoalescableExtInstr(const MachineInstr
&MI
,
649 unsigned &SrcReg
, unsigned &DstReg
,
650 unsigned &SubIdx
) const;
652 unsigned isLoadFromStackSlot(const MachineInstr
*MI
, int &FrameIndex
) const;
653 /// isLoadFromStackSlotPostFE - Check for post-frame ptr elimination
654 /// stack locations as well. This uses a heuristic so it isn't
655 /// reliable for correctness.
656 unsigned isLoadFromStackSlotPostFE(const MachineInstr
*MI
,
657 int &FrameIndex
) const;
659 /// hasLoadFromStackSlot - If the specified machine instruction has
660 /// a load from a stack slot, return true along with the FrameIndex
661 /// of the loaded stack slot and the machine mem operand containing
662 /// the reference. If not, return false. Unlike
663 /// isLoadFromStackSlot, this returns true for any instructions that
664 /// loads from the stack. This is a hint only and may not catch all
666 bool hasLoadFromStackSlot(const MachineInstr
*MI
,
667 const MachineMemOperand
*&MMO
,
668 int &FrameIndex
) const;
670 unsigned isStoreToStackSlot(const MachineInstr
*MI
, int &FrameIndex
) const;
671 /// isStoreToStackSlotPostFE - Check for post-frame ptr elimination
672 /// stack locations as well. This uses a heuristic so it isn't
673 /// reliable for correctness.
674 unsigned isStoreToStackSlotPostFE(const MachineInstr
*MI
,
675 int &FrameIndex
) const;
677 /// hasStoreToStackSlot - If the specified machine instruction has a
678 /// store to a stack slot, return true along with the FrameIndex of
679 /// the loaded stack slot and the machine mem operand containing the
680 /// reference. If not, return false. Unlike isStoreToStackSlot,
681 /// this returns true for any instructions that loads from the
682 /// stack. This is a hint only and may not catch all cases.
683 bool hasStoreToStackSlot(const MachineInstr
*MI
,
684 const MachineMemOperand
*&MMO
,
685 int &FrameIndex
) const;
687 bool isReallyTriviallyReMaterializable(const MachineInstr
*MI
,
688 AliasAnalysis
*AA
) const;
689 void reMaterialize(MachineBasicBlock
&MBB
, MachineBasicBlock::iterator MI
,
690 unsigned DestReg
, unsigned SubIdx
,
691 const MachineInstr
*Orig
,
692 const TargetRegisterInfo
&TRI
) const;
694 /// convertToThreeAddress - This method must be implemented by targets that
695 /// set the M_CONVERTIBLE_TO_3_ADDR flag. When this flag is set, the target
696 /// may be able to convert a two-address instruction into a true
697 /// three-address instruction on demand. This allows the X86 target (for
698 /// example) to convert ADD and SHL instructions into LEA instructions if they
699 /// would require register copies due to two-addressness.
701 /// This method returns a null pointer if the transformation cannot be
702 /// performed, otherwise it returns the new instruction.
704 virtual MachineInstr
*convertToThreeAddress(MachineFunction::iterator
&MFI
,
705 MachineBasicBlock::iterator
&MBBI
,
706 LiveVariables
*LV
) const;
708 /// commuteInstruction - We have a few instructions that must be hacked on to
711 virtual MachineInstr
*commuteInstruction(MachineInstr
*MI
, bool NewMI
) const;
714 virtual bool isUnpredicatedTerminator(const MachineInstr
* MI
) const;
715 virtual bool AnalyzeBranch(MachineBasicBlock
&MBB
, MachineBasicBlock
*&TBB
,
716 MachineBasicBlock
*&FBB
,
717 SmallVectorImpl
<MachineOperand
> &Cond
,
718 bool AllowModify
) const;
719 virtual unsigned RemoveBranch(MachineBasicBlock
&MBB
) const;
720 virtual unsigned InsertBranch(MachineBasicBlock
&MBB
, MachineBasicBlock
*TBB
,
721 MachineBasicBlock
*FBB
,
722 const SmallVectorImpl
<MachineOperand
> &Cond
,
724 virtual void copyPhysReg(MachineBasicBlock
&MBB
,
725 MachineBasicBlock::iterator MI
, DebugLoc DL
,
726 unsigned DestReg
, unsigned SrcReg
,
728 virtual void storeRegToStackSlot(MachineBasicBlock
&MBB
,
729 MachineBasicBlock::iterator MI
,
730 unsigned SrcReg
, bool isKill
, int FrameIndex
,
731 const TargetRegisterClass
*RC
,
732 const TargetRegisterInfo
*TRI
) const;
734 virtual void storeRegToAddr(MachineFunction
&MF
, unsigned SrcReg
, bool isKill
,
735 SmallVectorImpl
<MachineOperand
> &Addr
,
736 const TargetRegisterClass
*RC
,
737 MachineInstr::mmo_iterator MMOBegin
,
738 MachineInstr::mmo_iterator MMOEnd
,
739 SmallVectorImpl
<MachineInstr
*> &NewMIs
) const;
741 virtual void loadRegFromStackSlot(MachineBasicBlock
&MBB
,
742 MachineBasicBlock::iterator MI
,
743 unsigned DestReg
, int FrameIndex
,
744 const TargetRegisterClass
*RC
,
745 const TargetRegisterInfo
*TRI
) const;
747 virtual void loadRegFromAddr(MachineFunction
&MF
, unsigned DestReg
,
748 SmallVectorImpl
<MachineOperand
> &Addr
,
749 const TargetRegisterClass
*RC
,
750 MachineInstr::mmo_iterator MMOBegin
,
751 MachineInstr::mmo_iterator MMOEnd
,
752 SmallVectorImpl
<MachineInstr
*> &NewMIs
) const;
754 MachineInstr
*emitFrameIndexDebugValue(MachineFunction
&MF
,
755 int FrameIx
, uint64_t Offset
,
759 /// foldMemoryOperand - If this target supports it, fold a load or store of
760 /// the specified stack slot into the specified machine instruction for the
761 /// specified operand(s). If this is possible, the target should perform the
762 /// folding and return true, otherwise it should return false. If it folds
763 /// the instruction, it is likely that the MachineInstruction the iterator
764 /// references has been changed.
765 virtual MachineInstr
* foldMemoryOperandImpl(MachineFunction
&MF
,
767 const SmallVectorImpl
<unsigned> &Ops
,
768 int FrameIndex
) const;
770 /// foldMemoryOperand - Same as the previous version except it allows folding
771 /// of any load and store from / to any address, not just from a specific
773 virtual MachineInstr
* foldMemoryOperandImpl(MachineFunction
&MF
,
775 const SmallVectorImpl
<unsigned> &Ops
,
776 MachineInstr
* LoadMI
) const;
778 /// canFoldMemoryOperand - Returns true if the specified load / store is
779 /// folding is possible.
780 virtual bool canFoldMemoryOperand(const MachineInstr
*,
781 const SmallVectorImpl
<unsigned> &) const;
783 /// unfoldMemoryOperand - Separate a single instruction which folded a load or
784 /// a store or a load and a store into two or more instruction. If this is
785 /// possible, returns true as well as the new instructions by reference.
786 virtual bool unfoldMemoryOperand(MachineFunction
&MF
, MachineInstr
*MI
,
787 unsigned Reg
, bool UnfoldLoad
, bool UnfoldStore
,
788 SmallVectorImpl
<MachineInstr
*> &NewMIs
) const;
790 virtual bool unfoldMemoryOperand(SelectionDAG
&DAG
, SDNode
*N
,
791 SmallVectorImpl
<SDNode
*> &NewNodes
) const;
793 /// getOpcodeAfterMemoryUnfold - Returns the opcode of the would be new
794 /// instruction after load / store are unfolded from an instruction of the
795 /// specified opcode. It returns zero if the specified unfolding is not
796 /// possible. If LoadRegIndex is non-null, it is filled in with the operand
797 /// index of the operand which will hold the register holding the loaded
799 virtual unsigned getOpcodeAfterMemoryUnfold(unsigned Opc
,
800 bool UnfoldLoad
, bool UnfoldStore
,
801 unsigned *LoadRegIndex
= 0) const;
803 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler
804 /// to determine if two loads are loading from the same base address. It
805 /// should only return true if the base pointers are the same and the
806 /// only differences between the two addresses are the offset. It also returns
807 /// the offsets by reference.
808 virtual bool areLoadsFromSameBasePtr(SDNode
*Load1
, SDNode
*Load2
,
809 int64_t &Offset1
, int64_t &Offset2
) const;
811 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
812 /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should
813 /// be scheduled togther. On some targets if two loads are loading from
814 /// addresses in the same cache line, it's better if they are scheduled
815 /// together. This function takes two integers that represent the load offsets
816 /// from the common base address. It returns true if it decides it's desirable
817 /// to schedule the two loads together. "NumLoads" is the number of loads that
818 /// have already been scheduled after Load1.
819 virtual bool shouldScheduleLoadsNear(SDNode
*Load1
, SDNode
*Load2
,
820 int64_t Offset1
, int64_t Offset2
,
821 unsigned NumLoads
) const;
823 virtual void getNoopForMachoTarget(MCInst
&NopInst
) const;
826 bool ReverseBranchCondition(SmallVectorImpl
<MachineOperand
> &Cond
) const;
828 /// isSafeToMoveRegClassDefs - Return true if it's safe to move a machine
829 /// instruction that defines the specified register class.
830 bool isSafeToMoveRegClassDefs(const TargetRegisterClass
*RC
) const;
832 static bool isX86_64NonExtLowByteReg(unsigned reg
) {
833 return (reg
== X86::SPL
|| reg
== X86::BPL
||
834 reg
== X86::SIL
|| reg
== X86::DIL
);
837 static bool isX86_64ExtendedReg(const MachineOperand
&MO
) {
838 if (!MO
.isReg()) return false;
839 return isX86_64ExtendedReg(MO
.getReg());
842 /// isX86_64ExtendedReg - Is the MachineOperand a x86-64 extended (r8 or
843 /// higher) register? e.g. r8, xmm8, xmm13, etc.
844 static bool isX86_64ExtendedReg(unsigned RegNo
);
846 /// getGlobalBaseReg - Return a virtual register initialized with the
847 /// the global base register value. Output instructions required to
848 /// initialize the register in the function entry block, if necessary.
850 unsigned getGlobalBaseReg(MachineFunction
*MF
) const;
852 /// GetSSEDomain - Return the SSE execution domain of MI as the first element,
853 /// and a bitmask of possible arguments to SetSSEDomain ase the second.
854 std::pair
<uint16_t, uint16_t> GetSSEDomain(const MachineInstr
*MI
) const;
856 /// SetSSEDomain - Set the SSEDomain of MI.
857 void SetSSEDomain(MachineInstr
*MI
, unsigned Domain
) const;
859 MachineInstr
* foldMemoryOperandImpl(MachineFunction
&MF
,
862 const SmallVectorImpl
<MachineOperand
> &MOs
,
863 unsigned Size
, unsigned Alignment
) const;
865 bool isHighLatencyDef(int opc
) const;
867 bool hasHighOperandLatency(const InstrItineraryData
*ItinData
,
868 const MachineRegisterInfo
*MRI
,
869 const MachineInstr
*DefMI
, unsigned DefIdx
,
870 const MachineInstr
*UseMI
, unsigned UseIdx
) const;
873 MachineInstr
* convertToThreeAddressWithLEA(unsigned MIOpc
,
874 MachineFunction::iterator
&MFI
,
875 MachineBasicBlock::iterator
&MBBI
,
876 LiveVariables
*LV
) const;
878 /// isFrameOperand - Return true and the FrameIndex if the specified
879 /// operand and follow operands form a reference to the stack frame.
880 bool isFrameOperand(const MachineInstr
*MI
, unsigned int Op
,
881 int &FrameIndex
) const;
884 } // End llvm namespace