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"
23 class X86RegisterInfo
;
24 class X86TargetMachine
;
27 // Enums for memory operand decoding. Each memory operand is represented with
28 // a 5 operand sequence in the form:
29 // [BaseReg, ScaleAmt, IndexReg, Disp, Segment]
30 // These enums help decode this.
37 /// AddrSegmentReg - The operand # of the segment in the memory operand.
40 /// AddrNumOperands - Total number of operands in a memory reference.
45 // X86 specific condition code. These correspond to X86_*_COND in
46 // X86InstrInfo.td. They must be kept in synch.
65 // Artificial condition codes. These are used by AnalyzeBranch
66 // to indicate a block terminated with two conditional branches to
67 // the same location. This occurs in code using FCMP_OEQ or FCMP_UNE,
68 // which can't be represented on x86 with a single condition. These
69 // are never used in MachineInstrs.
76 // Turn condition code into conditional branch opcode.
77 unsigned GetCondBranchFromCond(CondCode CC
);
79 /// GetOppositeBranchCondition - Return the inverse of the specified cond,
80 /// e.g. turning COND_E to COND_NE.
81 CondCode
GetOppositeBranchCondition(X86::CondCode CC
);
85 /// X86II - This namespace holds all of the target specific flags that
86 /// instruction info tracks.
89 /// Target Operand Flag enum.
91 //===------------------------------------------------------------------===//
92 // X86 Specific MachineOperand flags.
96 /// MO_GOT_ABSOLUTE_ADDRESS - On a symbol operand, this represents a
98 /// SYMBOL_LABEL + [. - PICBASELABEL]
99 MO_GOT_ABSOLUTE_ADDRESS
,
101 /// MO_PIC_BASE_OFFSET - On a symbol operand this indicates that the
102 /// immediate should get the value of the symbol minus the PIC base label:
103 /// SYMBOL_LABEL - PICBASELABEL
106 /// MO_GOT - On a symbol operand this indicates that the immediate is the
107 /// offset to the GOT entry for the symbol name from the base of the GOT.
109 /// See the X86-64 ELF ABI supplement for more details.
110 /// SYMBOL_LABEL @GOT
113 /// MO_GOTOFF - On a symbol operand this indicates that the immediate is
114 /// the offset to the location of the symbol name from the base of the GOT.
116 /// See the X86-64 ELF ABI supplement for more details.
117 /// SYMBOL_LABEL @GOTOFF
120 /// MO_GOTPCREL - On a symbol operand this indicates that the immediate is
121 /// offset to the GOT entry for the symbol name from the current code
124 /// See the X86-64 ELF ABI supplement for more details.
125 /// SYMBOL_LABEL @GOTPCREL
128 /// MO_PLT - On a symbol operand this indicates that the immediate is
129 /// offset to the PLT entry of symbol name from the current code location.
131 /// See the X86-64 ELF ABI supplement for more details.
132 /// SYMBOL_LABEL @PLT
135 /// MO_TLSGD - On a symbol operand this indicates that the immediate is
138 /// See 'ELF Handling for Thread-Local Storage' for more details.
139 /// SYMBOL_LABEL @TLSGD
142 /// MO_GOTTPOFF - On a symbol operand this indicates that the immediate is
145 /// See 'ELF Handling for Thread-Local Storage' for more details.
146 /// SYMBOL_LABEL @GOTTPOFF
149 /// MO_INDNTPOFF - On a symbol operand this indicates that the immediate is
152 /// See 'ELF Handling for Thread-Local Storage' for more details.
153 /// SYMBOL_LABEL @INDNTPOFF
156 /// MO_TPOFF - On a symbol operand this indicates that the immediate is
159 /// See 'ELF Handling for Thread-Local Storage' for more details.
160 /// SYMBOL_LABEL @TPOFF
163 /// MO_NTPOFF - On a symbol operand this indicates that the immediate is
166 /// See 'ELF Handling for Thread-Local Storage' for more details.
167 /// SYMBOL_LABEL @NTPOFF
170 /// MO_DLLIMPORT - On a symbol operand "FOO", this indicates that the
171 /// reference is actually to the "__imp_FOO" symbol. This is used for
172 /// dllimport linkage on windows.
175 /// MO_DARWIN_STUB - On a symbol operand "FOO", this indicates that the
176 /// reference is actually to the "FOO$stub" symbol. This is used for calls
177 /// and jumps to external functions on Tiger and earlier.
180 /// MO_DARWIN_NONLAZY - On a symbol operand "FOO", this indicates that the
181 /// reference is actually to the "FOO$non_lazy_ptr" symbol, which is a
182 /// non-PIC-base-relative reference to a non-hidden dyld lazy pointer stub.
185 /// MO_DARWIN_NONLAZY_PIC_BASE - On a symbol operand "FOO", this indicates
186 /// that the reference is actually to "FOO$non_lazy_ptr - PICBASE", which is
187 /// a PIC-base-relative reference to a non-hidden dyld lazy pointer stub.
188 MO_DARWIN_NONLAZY_PIC_BASE
,
190 /// MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE - On a symbol operand "FOO", this
191 /// indicates that the reference is actually to "FOO$non_lazy_ptr -PICBASE",
192 /// which is a PIC-base-relative reference to a hidden dyld lazy pointer
194 MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE
,
196 /// MO_TLVP - On a symbol operand this indicates that the immediate is
199 /// This is the TLS offset for the Darwin TLS mechanism.
202 /// MO_TLVP_PIC_BASE - On a symbol operand this indicates that the immediate
203 /// is some TLS offset from the picbase.
205 /// This is the 32-bit TLS offset for Darwin TLS in PIC mode.
210 /// isGlobalStubReference - Return true if the specified TargetFlag operand is
211 /// a reference to a stub for a global, not the global itself.
212 inline static bool isGlobalStubReference(unsigned char TargetFlag
) {
213 switch (TargetFlag
) {
214 case X86II::MO_DLLIMPORT
: // dllimport stub.
215 case X86II::MO_GOTPCREL
: // rip-relative GOT reference.
216 case X86II::MO_GOT
: // normal GOT reference.
217 case X86II::MO_DARWIN_NONLAZY_PIC_BASE
: // Normal $non_lazy_ptr ref.
218 case X86II::MO_DARWIN_NONLAZY
: // Normal $non_lazy_ptr ref.
219 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE
: // Hidden $non_lazy_ptr ref.
226 /// isGlobalRelativeToPICBase - Return true if the specified global value
227 /// reference is relative to a 32-bit PIC base (X86ISD::GlobalBaseReg). If this
228 /// is true, the addressing mode has the PIC base register added in (e.g. EBX).
229 inline static bool isGlobalRelativeToPICBase(unsigned char TargetFlag
) {
230 switch (TargetFlag
) {
231 case X86II::MO_GOTOFF
: // isPICStyleGOT: local global.
232 case X86II::MO_GOT
: // isPICStyleGOT: other global.
233 case X86II::MO_PIC_BASE_OFFSET
: // Darwin local global.
234 case X86II::MO_DARWIN_NONLAZY_PIC_BASE
: // Darwin/32 external global.
235 case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE
: // Darwin/32 hidden global.
236 case X86II::MO_TLVP
: // ??? Pretty sure..
243 /// X86II - This namespace holds all of the target specific flags that
244 /// instruction info tracks.
248 //===------------------------------------------------------------------===//
249 // Instruction encodings. These are the standard/most common forms for X86
253 // PseudoFrm - This represents an instruction that is a pseudo instruction
254 // or one that has not been implemented yet. It is illegal to code generate
255 // it, but tolerated for intermediate implementation stages.
258 /// Raw - This form is for instructions that don't have any operands, so
259 /// they are just a fixed opcode value, like 'leave'.
262 /// AddRegFrm - This form is used for instructions like 'push r32' that have
263 /// their one register operand added to their opcode.
266 /// MRMDestReg - This form is used for instructions that use the Mod/RM byte
267 /// to specify a destination, which in this case is a register.
271 /// MRMDestMem - This form is used for instructions that use the Mod/RM byte
272 /// to specify a destination, which in this case is memory.
276 /// MRMSrcReg - This form is used for instructions that use the Mod/RM byte
277 /// to specify a source, which in this case is a register.
281 /// MRMSrcMem - This form is used for instructions that use the Mod/RM byte
282 /// to specify a source, which in this case is memory.
286 /// MRM[0-7][rm] - These forms are used to represent instructions that use
287 /// a Mod/RM byte, and use the middle field to hold extended opcode
288 /// information. In the intel manual these are represented as /0, /1, ...
291 // First, instructions that operate on a register r/m operand...
292 MRM0r
= 16, MRM1r
= 17, MRM2r
= 18, MRM3r
= 19, // Format /0 /1 /2 /3
293 MRM4r
= 20, MRM5r
= 21, MRM6r
= 22, MRM7r
= 23, // Format /4 /5 /6 /7
295 // Next, instructions that operate on a memory r/m operand...
296 MRM0m
= 24, MRM1m
= 25, MRM2m
= 26, MRM3m
= 27, // Format /0 /1 /2 /3
297 MRM4m
= 28, MRM5m
= 29, MRM6m
= 30, MRM7m
= 31, // Format /4 /5 /6 /7
299 // MRMInitReg - This form is used for instructions whose source and
300 // destinations are the same register.
303 //// MRM_C1 - A mod/rm byte of exactly 0xC1.
317 /// RawFrmImm8 - This is used for the ENTER instruction, which has two
318 /// immediates, the first of which is a 16-bit immediate (specified by
319 /// the imm encoding) and the second is a 8-bit fixed value.
322 /// RawFrmImm16 - This is used for CALL FAR instructions, which have two
323 /// immediates, the first of which is a 16 or 32-bit immediate (specified by
324 /// the imm encoding) and the second is a 16-bit fixed value. In the AMD
325 /// manual, this operand is described as pntr16:32 and pntr16:16
330 //===------------------------------------------------------------------===//
333 // OpSize - Set if this instruction requires an operand size prefix (0x66),
334 // which most often indicates that the instruction operates on 16 bit data
335 // instead of 32 bit data.
338 // AsSize - Set if this instruction requires an operand size prefix (0x67),
339 // which most often indicates that the instruction address 16 bit address
340 // instead of 32 bit address (or 32 bit address in 64 bit mode).
343 //===------------------------------------------------------------------===//
344 // Op0Mask - There are several prefix bytes that are used to form two byte
345 // opcodes. These are currently 0x0F, 0xF3, and 0xD8-0xDF. This mask is
346 // used to obtain the setting of this field. If no bits in this field is
347 // set, there is no prefix byte for obtaining a multibyte opcode.
350 Op0Mask
= 0x1F << Op0Shift
,
352 // TB - TwoByte - Set if this instruction has a two byte opcode, which
353 // starts with a 0x0F byte before the real opcode.
356 // REP - The 0xF3 prefix byte indicating repetition of the following
360 // D8-DF - These escape opcodes are used by the floating point unit. These
361 // values must remain sequential.
362 D8
= 3 << Op0Shift
, D9
= 4 << Op0Shift
,
363 DA
= 5 << Op0Shift
, DB
= 6 << Op0Shift
,
364 DC
= 7 << Op0Shift
, DD
= 8 << Op0Shift
,
365 DE
= 9 << Op0Shift
, DF
= 10 << Op0Shift
,
367 // XS, XD - These prefix codes are for single and double precision scalar
368 // floating point operations performed in the SSE registers.
369 XD
= 11 << Op0Shift
, XS
= 12 << Op0Shift
,
371 // T8, TA, A6, A7 - Prefix after the 0x0F prefix.
372 T8
= 13 << Op0Shift
, TA
= 14 << Op0Shift
,
373 A6
= 15 << Op0Shift
, A7
= 16 << Op0Shift
,
375 // TF - Prefix before and after 0x0F
378 //===------------------------------------------------------------------===//
379 // REX_W - REX prefixes are instruction prefixes used in 64-bit mode.
380 // They are used to specify GPRs and SSE registers, 64-bit operand size,
381 // etc. We only cares about REX.W and REX.R bits and only the former is
382 // statically determined.
384 REXShift
= Op0Shift
+ 5,
385 REX_W
= 1 << REXShift
,
387 //===------------------------------------------------------------------===//
388 // This three-bit field describes the size of an immediate operand. Zero is
389 // unused so that we can tell if we forgot to set a value.
390 ImmShift
= REXShift
+ 1,
391 ImmMask
= 7 << ImmShift
,
392 Imm8
= 1 << ImmShift
,
393 Imm8PCRel
= 2 << ImmShift
,
394 Imm16
= 3 << ImmShift
,
395 Imm16PCRel
= 4 << ImmShift
,
396 Imm32
= 5 << ImmShift
,
397 Imm32PCRel
= 6 << ImmShift
,
398 Imm64
= 7 << ImmShift
,
400 //===------------------------------------------------------------------===//
401 // FP Instruction Classification... Zero is non-fp instruction.
403 // FPTypeMask - Mask for all of the FP types...
404 FPTypeShift
= ImmShift
+ 3,
405 FPTypeMask
= 7 << FPTypeShift
,
407 // NotFP - The default, set for instructions that do not use FP registers.
408 NotFP
= 0 << FPTypeShift
,
410 // ZeroArgFP - 0 arg FP instruction which implicitly pushes ST(0), f.e. fld0
411 ZeroArgFP
= 1 << FPTypeShift
,
413 // OneArgFP - 1 arg FP instructions which implicitly read ST(0), such as fst
414 OneArgFP
= 2 << FPTypeShift
,
416 // OneArgFPRW - 1 arg FP instruction which implicitly read ST(0) and write a
417 // result back to ST(0). For example, fcos, fsqrt, etc.
419 OneArgFPRW
= 3 << FPTypeShift
,
421 // TwoArgFP - 2 arg FP instructions which implicitly read ST(0), and an
422 // explicit argument, storing the result to either ST(0) or the implicit
423 // argument. For example: fadd, fsub, fmul, etc...
424 TwoArgFP
= 4 << FPTypeShift
,
426 // CompareFP - 2 arg FP instructions which implicitly read ST(0) and an
427 // explicit argument, but have no destination. Example: fucom, fucomi, ...
428 CompareFP
= 5 << FPTypeShift
,
430 // CondMovFP - "2 operand" floating point conditional move instructions.
431 CondMovFP
= 6 << FPTypeShift
,
433 // SpecialFP - Special instruction forms. Dispatch by opcode explicitly.
434 SpecialFP
= 7 << FPTypeShift
,
437 LOCKShift
= FPTypeShift
+ 3,
438 LOCK
= 1 << LOCKShift
,
440 // Segment override prefixes. Currently we just need ability to address
441 // stuff in gs and fs segments.
442 SegOvrShift
= LOCKShift
+ 1,
443 SegOvrMask
= 3 << SegOvrShift
,
444 FS
= 1 << SegOvrShift
,
445 GS
= 2 << SegOvrShift
,
447 // Execution domain for SSE instructions in bits 23, 24.
448 // 0 in bits 23-24 means normal, non-SSE instruction.
449 SSEDomainShift
= SegOvrShift
+ 2,
451 OpcodeShift
= SSEDomainShift
+ 2,
452 OpcodeMask
= 0xFFULL
<< OpcodeShift
,
454 //===------------------------------------------------------------------===//
455 /// VEX - The opcode prefix used by AVX instructions
456 VEXShift
= OpcodeShift
+ 8,
459 /// VEX_W - Has a opcode specific functionality, but is used in the same
460 /// way as REX_W is for regular SSE instructions.
463 /// VEX_4V - Used to specify an additional AVX/SSE register. Several 2
464 /// address instructions in SSE are represented as 3 address ones in AVX
465 /// and the additional register is encoded in VEX_VVVV prefix.
468 /// VEX_I8IMM - Specifies that the last register used in a AVX instruction,
469 /// must be encoded in the i8 immediate field. This usually happens in
470 /// instructions with 4 operands.
473 /// VEX_L - Stands for a bit in the VEX opcode prefix meaning the current
474 /// instruction uses 256-bit wide registers. This is usually auto detected
475 /// if a VR256 register is used, but some AVX instructions also have this
476 /// field marked when using a f256 memory references.
479 /// Has3DNow0F0FOpcode - This flag indicates that the instruction uses the
480 /// wacky 0x0F 0x0F prefix for 3DNow! instructions. The manual documents
481 /// this as having a 0x0F prefix with a 0x0F opcode, and each instruction
482 /// storing a classifier in the imm8 field. To simplify our implementation,
483 /// we handle this by storeing the classifier in the opcode field and using
484 /// this flag to indicate that the encoder should do the wacky 3DNow! thing.
485 Has3DNow0F0FOpcode
= 1U << 5
488 // getBaseOpcodeFor - This function returns the "base" X86 opcode for the
489 // specified machine instruction.
491 static inline unsigned char getBaseOpcodeFor(uint64_t TSFlags
) {
492 return TSFlags
>> X86II::OpcodeShift
;
495 static inline bool hasImm(uint64_t TSFlags
) {
496 return (TSFlags
& X86II::ImmMask
) != 0;
499 /// getSizeOfImm - Decode the "size of immediate" field from the TSFlags field
500 /// of the specified instruction.
501 static inline unsigned getSizeOfImm(uint64_t TSFlags
) {
502 switch (TSFlags
& X86II::ImmMask
) {
503 default: assert(0 && "Unknown immediate size");
505 case X86II::Imm8PCRel
: return 1;
507 case X86II::Imm16PCRel
: return 2;
509 case X86II::Imm32PCRel
: return 4;
510 case X86II::Imm64
: return 8;
514 /// isImmPCRel - Return true if the immediate of the specified instruction's
515 /// TSFlags indicates that it is pc relative.
516 static inline unsigned isImmPCRel(uint64_t TSFlags
) {
517 switch (TSFlags
& X86II::ImmMask
) {
518 default: assert(0 && "Unknown immediate size");
519 case X86II::Imm8PCRel
:
520 case X86II::Imm16PCRel
:
521 case X86II::Imm32PCRel
:
531 /// getMemoryOperandNo - The function returns the MCInst operand # for the
532 /// first field of the memory operand. If the instruction doesn't have a
533 /// memory operand, this returns -1.
535 /// Note that this ignores tied operands. If there is a tied register which
536 /// is duplicated in the MCInst (e.g. "EAX = addl EAX, [mem]") it is only
537 /// counted as one operand.
539 static inline int getMemoryOperandNo(uint64_t TSFlags
) {
540 switch (TSFlags
& X86II::FormMask
) {
541 case X86II::MRMInitReg
: assert(0 && "FIXME: Remove this form");
542 default: assert(0 && "Unknown FormMask value in getMemoryOperandNo!");
545 case X86II::AddRegFrm
:
546 case X86II::MRMDestReg
:
547 case X86II::MRMSrcReg
:
548 case X86II::RawFrmImm8
:
549 case X86II::RawFrmImm16
:
551 case X86II::MRMDestMem
:
553 case X86II::MRMSrcMem
: {
554 bool HasVEX_4V
= (TSFlags
>> X86II::VEXShift
) & X86II::VEX_4V
;
555 unsigned FirstMemOp
= 1;
557 ++FirstMemOp
;// Skip the register source (which is encoded in VEX_VVVV).
559 // FIXME: Maybe lea should have its own form? This is a horrible hack.
560 //if (Opcode == X86::LEA64r || Opcode == X86::LEA64_32r ||
561 // Opcode == X86::LEA16r || Opcode == X86::LEA32r)
564 case X86II::MRM0r
: case X86II::MRM1r
:
565 case X86II::MRM2r
: case X86II::MRM3r
:
566 case X86II::MRM4r
: case X86II::MRM5r
:
567 case X86II::MRM6r
: case X86II::MRM7r
:
569 case X86II::MRM0m
: case X86II::MRM1m
:
570 case X86II::MRM2m
: case X86II::MRM3m
:
571 case X86II::MRM4m
: case X86II::MRM5m
:
572 case X86II::MRM6m
: case X86II::MRM7m
:
591 inline static bool isScale(const MachineOperand
&MO
) {
593 (MO
.getImm() == 1 || MO
.getImm() == 2 ||
594 MO
.getImm() == 4 || MO
.getImm() == 8);
597 inline static bool isLeaMem(const MachineInstr
*MI
, unsigned Op
) {
598 if (MI
->getOperand(Op
).isFI()) return true;
599 return Op
+4 <= MI
->getNumOperands() &&
600 MI
->getOperand(Op
).isReg() && isScale(MI
->getOperand(Op
+1)) &&
601 MI
->getOperand(Op
+2).isReg() &&
602 (MI
->getOperand(Op
+3).isImm() ||
603 MI
->getOperand(Op
+3).isGlobal() ||
604 MI
->getOperand(Op
+3).isCPI() ||
605 MI
->getOperand(Op
+3).isJTI());
608 inline static bool isMem(const MachineInstr
*MI
, unsigned Op
) {
609 if (MI
->getOperand(Op
).isFI()) return true;
610 return Op
+5 <= MI
->getNumOperands() &&
611 MI
->getOperand(Op
+4).isReg() &&
615 class X86InstrInfo
: public TargetInstrInfoImpl
{
616 X86TargetMachine
&TM
;
617 const X86RegisterInfo RI
;
619 /// RegOp2MemOpTable2Addr, RegOp2MemOpTable0, RegOp2MemOpTable1,
620 /// RegOp2MemOpTable2 - Load / store folding opcode maps.
622 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable2Addr
;
623 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable0
;
624 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable1
;
625 DenseMap
<unsigned, std::pair
<unsigned,unsigned> > RegOp2MemOpTable2
;
627 /// MemOp2RegOpTable - Load / store unfolding opcode map.
629 DenseMap
<unsigned, std::pair
<unsigned, unsigned> > MemOp2RegOpTable
;
632 explicit X86InstrInfo(X86TargetMachine
&tm
);
634 /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As
635 /// such, whenever a client has an instance of instruction info, it should
636 /// always be able to get register info as well (through this method).
638 virtual const X86RegisterInfo
&getRegisterInfo() const { return RI
; }
640 /// isCoalescableExtInstr - Return true if the instruction is a "coalescable"
641 /// extension instruction. That is, it's like a copy where it's legal for the
642 /// source to overlap the destination. e.g. X86::MOVSX64rr32. If this returns
643 /// true, then it's expected the pre-extension value is available as a subreg
644 /// of the result register. This also returns the sub-register index in
646 virtual bool isCoalescableExtInstr(const MachineInstr
&MI
,
647 unsigned &SrcReg
, unsigned &DstReg
,
648 unsigned &SubIdx
) const;
650 unsigned isLoadFromStackSlot(const MachineInstr
*MI
, int &FrameIndex
) const;
651 /// isLoadFromStackSlotPostFE - Check for post-frame ptr elimination
652 /// stack locations as well. This uses a heuristic so it isn't
653 /// reliable for correctness.
654 unsigned isLoadFromStackSlotPostFE(const MachineInstr
*MI
,
655 int &FrameIndex
) const;
657 /// hasLoadFromStackSlot - If the specified machine instruction has
658 /// a load from a stack slot, return true along with the FrameIndex
659 /// of the loaded stack slot and the machine mem operand containing
660 /// the reference. If not, return false. Unlike
661 /// isLoadFromStackSlot, this returns true for any instructions that
662 /// loads from the stack. This is a hint only and may not catch all
664 bool hasLoadFromStackSlot(const MachineInstr
*MI
,
665 const MachineMemOperand
*&MMO
,
666 int &FrameIndex
) const;
668 unsigned isStoreToStackSlot(const MachineInstr
*MI
, int &FrameIndex
) const;
669 /// isStoreToStackSlotPostFE - Check for post-frame ptr elimination
670 /// stack locations as well. This uses a heuristic so it isn't
671 /// reliable for correctness.
672 unsigned isStoreToStackSlotPostFE(const MachineInstr
*MI
,
673 int &FrameIndex
) const;
675 /// hasStoreToStackSlot - If the specified machine instruction has a
676 /// store to a stack slot, return true along with the FrameIndex of
677 /// the loaded stack slot and the machine mem operand containing the
678 /// reference. If not, return false. Unlike isStoreToStackSlot,
679 /// this returns true for any instructions that loads from the
680 /// stack. This is a hint only and may not catch all cases.
681 bool hasStoreToStackSlot(const MachineInstr
*MI
,
682 const MachineMemOperand
*&MMO
,
683 int &FrameIndex
) const;
685 bool isReallyTriviallyReMaterializable(const MachineInstr
*MI
,
686 AliasAnalysis
*AA
) const;
687 void reMaterialize(MachineBasicBlock
&MBB
, MachineBasicBlock::iterator MI
,
688 unsigned DestReg
, unsigned SubIdx
,
689 const MachineInstr
*Orig
,
690 const TargetRegisterInfo
&TRI
) const;
692 /// convertToThreeAddress - This method must be implemented by targets that
693 /// set the M_CONVERTIBLE_TO_3_ADDR flag. When this flag is set, the target
694 /// may be able to convert a two-address instruction into a true
695 /// three-address instruction on demand. This allows the X86 target (for
696 /// example) to convert ADD and SHL instructions into LEA instructions if they
697 /// would require register copies due to two-addressness.
699 /// This method returns a null pointer if the transformation cannot be
700 /// performed, otherwise it returns the new instruction.
702 virtual MachineInstr
*convertToThreeAddress(MachineFunction::iterator
&MFI
,
703 MachineBasicBlock::iterator
&MBBI
,
704 LiveVariables
*LV
) const;
706 /// commuteInstruction - We have a few instructions that must be hacked on to
709 virtual MachineInstr
*commuteInstruction(MachineInstr
*MI
, bool NewMI
) const;
712 virtual bool isUnpredicatedTerminator(const MachineInstr
* MI
) const;
713 virtual bool AnalyzeBranch(MachineBasicBlock
&MBB
, MachineBasicBlock
*&TBB
,
714 MachineBasicBlock
*&FBB
,
715 SmallVectorImpl
<MachineOperand
> &Cond
,
716 bool AllowModify
) const;
717 virtual unsigned RemoveBranch(MachineBasicBlock
&MBB
) const;
718 virtual unsigned InsertBranch(MachineBasicBlock
&MBB
, MachineBasicBlock
*TBB
,
719 MachineBasicBlock
*FBB
,
720 const SmallVectorImpl
<MachineOperand
> &Cond
,
722 virtual void copyPhysReg(MachineBasicBlock
&MBB
,
723 MachineBasicBlock::iterator MI
, DebugLoc DL
,
724 unsigned DestReg
, unsigned SrcReg
,
726 virtual void storeRegToStackSlot(MachineBasicBlock
&MBB
,
727 MachineBasicBlock::iterator MI
,
728 unsigned SrcReg
, bool isKill
, int FrameIndex
,
729 const TargetRegisterClass
*RC
,
730 const TargetRegisterInfo
*TRI
) const;
732 virtual void storeRegToAddr(MachineFunction
&MF
, unsigned SrcReg
, bool isKill
,
733 SmallVectorImpl
<MachineOperand
> &Addr
,
734 const TargetRegisterClass
*RC
,
735 MachineInstr::mmo_iterator MMOBegin
,
736 MachineInstr::mmo_iterator MMOEnd
,
737 SmallVectorImpl
<MachineInstr
*> &NewMIs
) const;
739 virtual void loadRegFromStackSlot(MachineBasicBlock
&MBB
,
740 MachineBasicBlock::iterator MI
,
741 unsigned DestReg
, int FrameIndex
,
742 const TargetRegisterClass
*RC
,
743 const TargetRegisterInfo
*TRI
) const;
745 virtual void loadRegFromAddr(MachineFunction
&MF
, unsigned DestReg
,
746 SmallVectorImpl
<MachineOperand
> &Addr
,
747 const TargetRegisterClass
*RC
,
748 MachineInstr::mmo_iterator MMOBegin
,
749 MachineInstr::mmo_iterator MMOEnd
,
750 SmallVectorImpl
<MachineInstr
*> &NewMIs
) const;
752 MachineInstr
*emitFrameIndexDebugValue(MachineFunction
&MF
,
753 int FrameIx
, uint64_t Offset
,
757 /// foldMemoryOperand - If this target supports it, fold a load or store of
758 /// the specified stack slot into the specified machine instruction for the
759 /// specified operand(s). If this is possible, the target should perform the
760 /// folding and return true, otherwise it should return false. If it folds
761 /// the instruction, it is likely that the MachineInstruction the iterator
762 /// references has been changed.
763 virtual MachineInstr
* foldMemoryOperandImpl(MachineFunction
&MF
,
765 const SmallVectorImpl
<unsigned> &Ops
,
766 int FrameIndex
) const;
768 /// foldMemoryOperand - Same as the previous version except it allows folding
769 /// of any load and store from / to any address, not just from a specific
771 virtual MachineInstr
* foldMemoryOperandImpl(MachineFunction
&MF
,
773 const SmallVectorImpl
<unsigned> &Ops
,
774 MachineInstr
* LoadMI
) const;
776 /// canFoldMemoryOperand - Returns true if the specified load / store is
777 /// folding is possible.
778 virtual bool canFoldMemoryOperand(const MachineInstr
*,
779 const SmallVectorImpl
<unsigned> &) const;
781 /// unfoldMemoryOperand - Separate a single instruction which folded a load or
782 /// a store or a load and a store into two or more instruction. If this is
783 /// possible, returns true as well as the new instructions by reference.
784 virtual bool unfoldMemoryOperand(MachineFunction
&MF
, MachineInstr
*MI
,
785 unsigned Reg
, bool UnfoldLoad
, bool UnfoldStore
,
786 SmallVectorImpl
<MachineInstr
*> &NewMIs
) const;
788 virtual bool unfoldMemoryOperand(SelectionDAG
&DAG
, SDNode
*N
,
789 SmallVectorImpl
<SDNode
*> &NewNodes
) const;
791 /// getOpcodeAfterMemoryUnfold - Returns the opcode of the would be new
792 /// instruction after load / store are unfolded from an instruction of the
793 /// specified opcode. It returns zero if the specified unfolding is not
794 /// possible. If LoadRegIndex is non-null, it is filled in with the operand
795 /// index of the operand which will hold the register holding the loaded
797 virtual unsigned getOpcodeAfterMemoryUnfold(unsigned Opc
,
798 bool UnfoldLoad
, bool UnfoldStore
,
799 unsigned *LoadRegIndex
= 0) const;
801 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler
802 /// to determine if two loads are loading from the same base address. It
803 /// should only return true if the base pointers are the same and the
804 /// only differences between the two addresses are the offset. It also returns
805 /// the offsets by reference.
806 virtual bool areLoadsFromSameBasePtr(SDNode
*Load1
, SDNode
*Load2
,
807 int64_t &Offset1
, int64_t &Offset2
) const;
809 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
810 /// determine (in conjuction with areLoadsFromSameBasePtr) if two loads should
811 /// be scheduled togther. On some targets if two loads are loading from
812 /// addresses in the same cache line, it's better if they are scheduled
813 /// together. This function takes two integers that represent the load offsets
814 /// from the common base address. It returns true if it decides it's desirable
815 /// to schedule the two loads together. "NumLoads" is the number of loads that
816 /// have already been scheduled after Load1.
817 virtual bool shouldScheduleLoadsNear(SDNode
*Load1
, SDNode
*Load2
,
818 int64_t Offset1
, int64_t Offset2
,
819 unsigned NumLoads
) const;
821 virtual void getNoopForMachoTarget(MCInst
&NopInst
) const;
824 bool ReverseBranchCondition(SmallVectorImpl
<MachineOperand
> &Cond
) const;
826 /// isSafeToMoveRegClassDefs - Return true if it's safe to move a machine
827 /// instruction that defines the specified register class.
828 bool isSafeToMoveRegClassDefs(const TargetRegisterClass
*RC
) const;
830 static bool isX86_64NonExtLowByteReg(unsigned reg
) {
831 return (reg
== X86::SPL
|| reg
== X86::BPL
||
832 reg
== X86::SIL
|| reg
== X86::DIL
);
835 static bool isX86_64ExtendedReg(const MachineOperand
&MO
) {
836 if (!MO
.isReg()) return false;
837 return isX86_64ExtendedReg(MO
.getReg());
840 /// isX86_64ExtendedReg - Is the MachineOperand a x86-64 extended (r8 or
841 /// higher) register? e.g. r8, xmm8, xmm13, etc.
842 static bool isX86_64ExtendedReg(unsigned RegNo
);
844 /// getGlobalBaseReg - Return a virtual register initialized with the
845 /// the global base register value. Output instructions required to
846 /// initialize the register in the function entry block, if necessary.
848 unsigned getGlobalBaseReg(MachineFunction
*MF
) const;
850 /// GetSSEDomain - Return the SSE execution domain of MI as the first element,
851 /// and a bitmask of possible arguments to SetSSEDomain ase the second.
852 std::pair
<uint16_t, uint16_t> GetSSEDomain(const MachineInstr
*MI
) const;
854 /// SetSSEDomain - Set the SSEDomain of MI.
855 void SetSSEDomain(MachineInstr
*MI
, unsigned Domain
) const;
857 MachineInstr
* foldMemoryOperandImpl(MachineFunction
&MF
,
860 const SmallVectorImpl
<MachineOperand
> &MOs
,
861 unsigned Size
, unsigned Alignment
) const;
863 bool isHighLatencyDef(int opc
) const;
865 bool hasHighOperandLatency(const InstrItineraryData
*ItinData
,
866 const MachineRegisterInfo
*MRI
,
867 const MachineInstr
*DefMI
, unsigned DefIdx
,
868 const MachineInstr
*UseMI
, unsigned UseIdx
) const;
871 MachineInstr
* convertToThreeAddressWithLEA(unsigned MIOpc
,
872 MachineFunction::iterator
&MFI
,
873 MachineBasicBlock::iterator
&MBBI
,
874 LiveVariables
*LV
) const;
876 /// isFrameOperand - Return true and the FrameIndex if the specified
877 /// operand and follow operands form a reference to the stack frame.
878 bool isFrameOperand(const MachineInstr
*MI
, unsigned int Op
,
879 int &FrameIndex
) const;
882 } // End llvm namespace