1 //===-- ARMAsmBackend.cpp - ARM Assembler Backend -------------------------===//
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 #include "MCTargetDesc/ARMMCTargetDesc.h"
11 #include "MCTargetDesc/ARMAddressingModes.h"
12 #include "MCTargetDesc/ARMAsmBackend.h"
13 #include "MCTargetDesc/ARMAsmBackendDarwin.h"
14 #include "MCTargetDesc/ARMAsmBackendELF.h"
15 #include "MCTargetDesc/ARMAsmBackendWinCOFF.h"
16 #include "MCTargetDesc/ARMBaseInfo.h"
17 #include "MCTargetDesc/ARMFixupKinds.h"
18 #include "llvm/ADT/StringSwitch.h"
19 #include "llvm/MC/MCAsmBackend.h"
20 #include "llvm/MC/MCAssembler.h"
21 #include "llvm/MC/MCContext.h"
22 #include "llvm/MC/MCDirectives.h"
23 #include "llvm/MC/MCELFObjectWriter.h"
24 #include "llvm/MC/MCExpr.h"
25 #include "llvm/MC/MCFixupKindInfo.h"
26 #include "llvm/MC/MCMachObjectWriter.h"
27 #include "llvm/MC/MCObjectWriter.h"
28 #include "llvm/MC/MCRegisterInfo.h"
29 #include "llvm/MC/MCSectionELF.h"
30 #include "llvm/MC/MCSectionMachO.h"
31 #include "llvm/MC/MCSubtargetInfo.h"
32 #include "llvm/MC/MCValue.h"
33 #include "llvm/Support/Debug.h"
34 #include "llvm/Support/ELF.h"
35 #include "llvm/Support/ErrorHandling.h"
36 #include "llvm/Support/Format.h"
37 #include "llvm/Support/MachO.h"
38 #include "llvm/Support/TargetParser.h"
39 #include "llvm/Support/raw_ostream.h"
43 class ARMELFObjectWriter : public MCELFObjectTargetWriter {
45 ARMELFObjectWriter(uint8_t OSABI)
46 : MCELFObjectTargetWriter(/*Is64Bit*/ false, OSABI, ELF::EM_ARM,
47 /*HasRelocationAddend*/ false) {}
49 } // end anonymous namespace
51 const MCFixupKindInfo &ARMAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
52 const static MCFixupKindInfo InfosLE[ARM::NumTargetFixupKinds] = {
53 // This table *must* be in the order that the fixup_* kinds are defined in
56 // Name Offset (bits) Size (bits) Flags
57 {"fixup_arm_ldst_pcrel_12", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
58 {"fixup_t2_ldst_pcrel_12", 0, 32,
59 MCFixupKindInfo::FKF_IsPCRel |
60 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
61 {"fixup_arm_pcrel_10_unscaled", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
62 {"fixup_arm_pcrel_10", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
63 {"fixup_t2_pcrel_10", 0, 32,
64 MCFixupKindInfo::FKF_IsPCRel |
65 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
66 {"fixup_arm_pcrel_9", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
67 {"fixup_t2_pcrel_9", 0, 32,
68 MCFixupKindInfo::FKF_IsPCRel |
69 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
70 {"fixup_thumb_adr_pcrel_10", 0, 8,
71 MCFixupKindInfo::FKF_IsPCRel |
72 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
73 {"fixup_arm_adr_pcrel_12", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
74 {"fixup_t2_adr_pcrel_12", 0, 32,
75 MCFixupKindInfo::FKF_IsPCRel |
76 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
77 {"fixup_arm_condbranch", 0, 24, MCFixupKindInfo::FKF_IsPCRel},
78 {"fixup_arm_uncondbranch", 0, 24, MCFixupKindInfo::FKF_IsPCRel},
79 {"fixup_t2_condbranch", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
80 {"fixup_t2_uncondbranch", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
81 {"fixup_arm_thumb_br", 0, 16, MCFixupKindInfo::FKF_IsPCRel},
82 {"fixup_arm_uncondbl", 0, 24, MCFixupKindInfo::FKF_IsPCRel},
83 {"fixup_arm_condbl", 0, 24, MCFixupKindInfo::FKF_IsPCRel},
84 {"fixup_arm_blx", 0, 24, MCFixupKindInfo::FKF_IsPCRel},
85 {"fixup_arm_thumb_bl", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
86 {"fixup_arm_thumb_blx", 0, 32,
87 MCFixupKindInfo::FKF_IsPCRel |
88 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
89 {"fixup_arm_thumb_cb", 0, 16, MCFixupKindInfo::FKF_IsPCRel},
90 {"fixup_arm_thumb_cp", 0, 8,
91 MCFixupKindInfo::FKF_IsPCRel |
92 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
93 {"fixup_arm_thumb_bcc", 0, 8, MCFixupKindInfo::FKF_IsPCRel},
94 // movw / movt: 16-bits immediate but scattered into two chunks 0 - 12, 16
96 {"fixup_arm_movt_hi16", 0, 20, 0},
97 {"fixup_arm_movw_lo16", 0, 20, 0},
98 {"fixup_t2_movt_hi16", 0, 20, 0},
99 {"fixup_t2_movw_lo16", 0, 20, 0},
100 {"fixup_arm_mod_imm", 0, 12, 0},
102 const static MCFixupKindInfo InfosBE[ARM::NumTargetFixupKinds] = {
103 // This table *must* be in the order that the fixup_* kinds are defined in
106 // Name Offset (bits) Size (bits) Flags
107 {"fixup_arm_ldst_pcrel_12", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
108 {"fixup_t2_ldst_pcrel_12", 0, 32,
109 MCFixupKindInfo::FKF_IsPCRel |
110 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
111 {"fixup_arm_pcrel_10_unscaled", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
112 {"fixup_arm_pcrel_10", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
113 {"fixup_t2_pcrel_10", 0, 32,
114 MCFixupKindInfo::FKF_IsPCRel |
115 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
116 {"fixup_arm_pcrel_9", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
117 {"fixup_t2_pcrel_9", 0, 32,
118 MCFixupKindInfo::FKF_IsPCRel |
119 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
120 {"fixup_thumb_adr_pcrel_10", 8, 8,
121 MCFixupKindInfo::FKF_IsPCRel |
122 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
123 {"fixup_arm_adr_pcrel_12", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
124 {"fixup_t2_adr_pcrel_12", 0, 32,
125 MCFixupKindInfo::FKF_IsPCRel |
126 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
127 {"fixup_arm_condbranch", 8, 24, MCFixupKindInfo::FKF_IsPCRel},
128 {"fixup_arm_uncondbranch", 8, 24, MCFixupKindInfo::FKF_IsPCRel},
129 {"fixup_t2_condbranch", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
130 {"fixup_t2_uncondbranch", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
131 {"fixup_arm_thumb_br", 0, 16, MCFixupKindInfo::FKF_IsPCRel},
132 {"fixup_arm_uncondbl", 8, 24, MCFixupKindInfo::FKF_IsPCRel},
133 {"fixup_arm_condbl", 8, 24, MCFixupKindInfo::FKF_IsPCRel},
134 {"fixup_arm_blx", 8, 24, MCFixupKindInfo::FKF_IsPCRel},
135 {"fixup_arm_thumb_bl", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
136 {"fixup_arm_thumb_blx", 0, 32,
137 MCFixupKindInfo::FKF_IsPCRel |
138 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
139 {"fixup_arm_thumb_cb", 0, 16, MCFixupKindInfo::FKF_IsPCRel},
140 {"fixup_arm_thumb_cp", 8, 8,
141 MCFixupKindInfo::FKF_IsPCRel |
142 MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
143 {"fixup_arm_thumb_bcc", 8, 8, MCFixupKindInfo::FKF_IsPCRel},
144 // movw / movt: 16-bits immediate but scattered into two chunks 0 - 12, 16
146 {"fixup_arm_movt_hi16", 12, 20, 0},
147 {"fixup_arm_movw_lo16", 12, 20, 0},
148 {"fixup_t2_movt_hi16", 12, 20, 0},
149 {"fixup_t2_movw_lo16", 12, 20, 0},
150 {"fixup_arm_mod_imm", 20, 12, 0},
153 if (Kind < FirstTargetFixupKind)
154 return MCAsmBackend::getFixupKindInfo(Kind);
156 assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
158 return (IsLittleEndian ? InfosLE : InfosBE)[Kind - FirstTargetFixupKind];
161 void ARMAsmBackend::handleAssemblerFlag(MCAssemblerFlag Flag) {
174 unsigned ARMAsmBackend::getRelaxedOpcode(unsigned Op) const {
175 bool HasThumb2 = STI->getFeatureBits()[ARM::FeatureThumb2];
176 bool HasV8MBaselineOps = STI->getFeatureBits()[ARM::HasV8MBaselineOps];
182 return HasThumb2 ? (unsigned)ARM::t2Bcc : Op;
184 return HasThumb2 ? (unsigned)ARM::t2LDRpci : Op;
186 return HasThumb2 ? (unsigned)ARM::t2ADR : Op;
188 return HasV8MBaselineOps ? (unsigned)ARM::t2B : Op;
196 bool ARMAsmBackend::mayNeedRelaxation(const MCInst &Inst) const {
197 if (getRelaxedOpcode(Inst.getOpcode()) != Inst.getOpcode())
202 const char *ARMAsmBackend::reasonForFixupRelaxation(const MCFixup &Fixup,
203 uint64_t Value) const {
204 switch ((unsigned)Fixup.getKind()) {
205 case ARM::fixup_arm_thumb_br: {
206 // Relaxing tB to t2B. tB has a signed 12-bit displacement with the
207 // low bit being an implied zero. There's an implied +4 offset for the
208 // branch, so we adjust the other way here to determine what's
211 // Relax if the value is too big for a (signed) i8.
212 int64_t Offset = int64_t(Value) - 4;
213 if (Offset > 2046 || Offset < -2048)
214 return "out of range pc-relative fixup value";
217 case ARM::fixup_arm_thumb_bcc: {
218 // Relaxing tBcc to t2Bcc. tBcc has a signed 9-bit displacement with the
219 // low bit being an implied zero. There's an implied +4 offset for the
220 // branch, so we adjust the other way here to determine what's
223 // Relax if the value is too big for a (signed) i8.
224 int64_t Offset = int64_t(Value) - 4;
225 if (Offset > 254 || Offset < -256)
226 return "out of range pc-relative fixup value";
229 case ARM::fixup_thumb_adr_pcrel_10:
230 case ARM::fixup_arm_thumb_cp: {
231 // If the immediate is negative, greater than 1020, or not a multiple
232 // of four, the wide version of the instruction must be used.
233 int64_t Offset = int64_t(Value) - 4;
235 return "misaligned pc-relative fixup value";
236 else if (Offset > 1020 || Offset < 0)
237 return "out of range pc-relative fixup value";
240 case ARM::fixup_arm_thumb_cb: {
241 // If we have a Thumb CBZ or CBNZ instruction and its target is the next
242 // instruction it is is actually out of range for the instruction.
243 // It will be changed to a NOP.
244 int64_t Offset = (Value & ~1);
246 return "will be converted to nop";
250 llvm_unreachable("Unexpected fixup kind in reasonForFixupRelaxation()!");
255 bool ARMAsmBackend::fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
256 const MCRelaxableFragment *DF,
257 const MCAsmLayout &Layout) const {
258 return reasonForFixupRelaxation(Fixup, Value);
261 void ARMAsmBackend::relaxInstruction(const MCInst &Inst,
262 const MCSubtargetInfo &STI,
264 unsigned RelaxedOp = getRelaxedOpcode(Inst.getOpcode());
266 // Sanity check w/ diagnostic if we get here w/ a bogus instruction.
267 if (RelaxedOp == Inst.getOpcode()) {
268 SmallString<256> Tmp;
269 raw_svector_ostream OS(Tmp);
270 Inst.dump_pretty(OS);
272 report_fatal_error("unexpected instruction to relax: " + OS.str());
275 // If we are changing Thumb CBZ or CBNZ instruction to a NOP, aka tHINT, we
276 // have to change the operands too.
277 if ((Inst.getOpcode() == ARM::tCBZ || Inst.getOpcode() == ARM::tCBNZ) &&
278 RelaxedOp == ARM::tHINT) {
279 Res.setOpcode(RelaxedOp);
280 Res.addOperand(MCOperand::createImm(0));
281 Res.addOperand(MCOperand::createImm(14));
282 Res.addOperand(MCOperand::createReg(0));
286 // The rest of instructions we're relaxing have the same operands.
287 // We just need to update to the proper opcode.
289 Res.setOpcode(RelaxedOp);
292 bool ARMAsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const {
293 const uint16_t Thumb1_16bitNopEncoding = 0x46c0; // using MOV r8,r8
294 const uint16_t Thumb2_16bitNopEncoding = 0xbf00; // NOP
295 const uint32_t ARMv4_NopEncoding = 0xe1a00000; // using MOV r0,r0
296 const uint32_t ARMv6T2_NopEncoding = 0xe320f000; // NOP
298 const uint16_t nopEncoding =
299 hasNOP() ? Thumb2_16bitNopEncoding : Thumb1_16bitNopEncoding;
300 uint64_t NumNops = Count / 2;
301 for (uint64_t i = 0; i != NumNops; ++i)
302 OW->write16(nopEncoding);
308 const uint32_t nopEncoding =
309 hasNOP() ? ARMv6T2_NopEncoding : ARMv4_NopEncoding;
310 uint64_t NumNops = Count / 4;
311 for (uint64_t i = 0; i != NumNops; ++i)
312 OW->write32(nopEncoding);
313 // FIXME: should this function return false when unable to write exactly
314 // 'Count' bytes with NOP encodings?
317 break; // No leftover bytes to write
333 static uint32_t swapHalfWords(uint32_t Value, bool IsLittleEndian) {
334 if (IsLittleEndian) {
335 // Note that the halfwords are stored high first and low second in thumb;
336 // so we need to swap the fixup value here to map properly.
337 uint32_t Swapped = (Value & 0xFFFF0000) >> 16;
338 Swapped |= (Value & 0x0000FFFF) << 16;
344 static uint32_t joinHalfWords(uint32_t FirstHalf, uint32_t SecondHalf,
345 bool IsLittleEndian) {
348 if (IsLittleEndian) {
349 Value = (SecondHalf & 0xFFFF) << 16;
350 Value |= (FirstHalf & 0xFFFF);
352 Value = (SecondHalf & 0xFFFF);
353 Value |= (FirstHalf & 0xFFFF) << 16;
359 unsigned ARMAsmBackend::adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
360 bool IsPCRel, MCContext &Ctx,
362 bool IsResolved) const {
363 unsigned Kind = Fixup.getKind();
366 Ctx.reportError(Fixup.getLoc(), "bad relocation fixup type");
376 case ARM::fixup_arm_movt_hi16:
380 case ARM::fixup_arm_movw_lo16: {
381 unsigned Hi4 = (Value & 0xF000) >> 12;
382 unsigned Lo12 = Value & 0x0FFF;
383 // inst{19-16} = Hi4;
384 // inst{11-0} = Lo12;
385 Value = (Hi4 << 16) | (Lo12);
388 case ARM::fixup_t2_movt_hi16:
392 case ARM::fixup_t2_movw_lo16: {
393 unsigned Hi4 = (Value & 0xF000) >> 12;
394 unsigned i = (Value & 0x800) >> 11;
395 unsigned Mid3 = (Value & 0x700) >> 8;
396 unsigned Lo8 = Value & 0x0FF;
397 // inst{19-16} = Hi4;
399 // inst{14-12} = Mid3;
401 Value = (Hi4 << 16) | (i << 26) | (Mid3 << 12) | (Lo8);
402 return swapHalfWords(Value, IsLittleEndian);
404 case ARM::fixup_arm_ldst_pcrel_12:
405 // ARM PC-relative values are offset by 8.
408 case ARM::fixup_t2_ldst_pcrel_12: {
409 // Offset by 4, adjusted by two due to the half-word ordering of thumb.
412 if ((int64_t)Value < 0) {
417 Ctx.reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
420 Value |= isAdd << 23;
422 // Same addressing mode as fixup_arm_pcrel_10,
423 // but with 16-bit halfwords swapped.
424 if (Kind == ARM::fixup_t2_ldst_pcrel_12)
425 return swapHalfWords(Value, IsLittleEndian);
429 case ARM::fixup_arm_adr_pcrel_12: {
430 // ARM PC-relative values are offset by 8.
432 unsigned opc = 4; // bits {24-21}. Default to add: 0b0100
433 if ((int64_t)Value < 0) {
437 if (ARM_AM::getSOImmVal(Value) == -1) {
438 Ctx.reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
441 // Encode the immediate and shift the opcode into place.
442 return ARM_AM::getSOImmVal(Value) | (opc << 21);
445 case ARM::fixup_t2_adr_pcrel_12: {
448 if ((int64_t)Value < 0) {
453 uint32_t out = (opc << 21);
454 out |= (Value & 0x800) << 15;
455 out |= (Value & 0x700) << 4;
456 out |= (Value & 0x0FF);
458 return swapHalfWords(out, IsLittleEndian);
461 case ARM::fixup_arm_condbranch:
462 case ARM::fixup_arm_uncondbranch:
463 case ARM::fixup_arm_uncondbl:
464 case ARM::fixup_arm_condbl:
465 case ARM::fixup_arm_blx:
466 // These values don't encode the low two bits since they're always zero.
467 // Offset by 8 just as above.
468 if (const MCSymbolRefExpr *SRE =
469 dyn_cast<MCSymbolRefExpr>(Fixup.getValue()))
470 if (SRE->getKind() == MCSymbolRefExpr::VK_TLSCALL)
472 return 0xffffff & ((Value - 8) >> 2);
473 case ARM::fixup_t2_uncondbranch: {
475 Value >>= 1; // Low bit is not encoded.
478 bool I = Value & 0x800000;
479 bool J1 = Value & 0x400000;
480 bool J2 = Value & 0x200000;
484 out |= I << 26; // S bit
485 out |= !J1 << 13; // J1 bit
486 out |= !J2 << 11; // J2 bit
487 out |= (Value & 0x1FF800) << 5; // imm6 field
488 out |= (Value & 0x0007FF); // imm11 field
490 return swapHalfWords(out, IsLittleEndian);
492 case ARM::fixup_t2_condbranch: {
494 Value >>= 1; // Low bit is not encoded.
497 out |= (Value & 0x80000) << 7; // S bit
498 out |= (Value & 0x40000) >> 7; // J2 bit
499 out |= (Value & 0x20000) >> 4; // J1 bit
500 out |= (Value & 0x1F800) << 5; // imm6 field
501 out |= (Value & 0x007FF); // imm11 field
503 return swapHalfWords(out, IsLittleEndian);
505 case ARM::fixup_arm_thumb_bl: {
506 // The value doesn't encode the low bit (always zero) and is offset by
507 // four. The 32-bit immediate value is encoded as
508 // imm32 = SignExtend(S:I1:I2:imm10:imm11:0)
509 // where I1 = NOT(J1 ^ S) and I2 = NOT(J2 ^ S).
510 // The value is encoded into disjoint bit positions in the destination
511 // opcode. x = unchanged, I = immediate value bit, S = sign extension bit,
512 // J = either J1 or J2 bit
514 // BL: xxxxxSIIIIIIIIII xxJxJIIIIIIIIIII
516 // Note that the halfwords are stored high first, low second; so we need
517 // to transpose the fixup value here to map properly.
518 uint32_t offset = (Value - 4) >> 1;
519 uint32_t signBit = (offset & 0x800000) >> 23;
520 uint32_t I1Bit = (offset & 0x400000) >> 22;
521 uint32_t J1Bit = (I1Bit ^ 0x1) ^ signBit;
522 uint32_t I2Bit = (offset & 0x200000) >> 21;
523 uint32_t J2Bit = (I2Bit ^ 0x1) ^ signBit;
524 uint32_t imm10Bits = (offset & 0x1FF800) >> 11;
525 uint32_t imm11Bits = (offset & 0x000007FF);
527 uint32_t FirstHalf = (((uint16_t)signBit << 10) | (uint16_t)imm10Bits);
528 uint32_t SecondHalf = (((uint16_t)J1Bit << 13) | ((uint16_t)J2Bit << 11) |
529 (uint16_t)imm11Bits);
530 return joinHalfWords(FirstHalf, SecondHalf, IsLittleEndian);
532 case ARM::fixup_arm_thumb_blx: {
533 // The value doesn't encode the low two bits (always zero) and is offset by
534 // four (see fixup_arm_thumb_cp). The 32-bit immediate value is encoded as
535 // imm32 = SignExtend(S:I1:I2:imm10H:imm10L:00)
536 // where I1 = NOT(J1 ^ S) and I2 = NOT(J2 ^ S).
537 // The value is encoded into disjoint bit positions in the destination
538 // opcode. x = unchanged, I = immediate value bit, S = sign extension bit,
539 // J = either J1 or J2 bit, 0 = zero.
541 // BLX: xxxxxSIIIIIIIIII xxJxJIIIIIIIIII0
543 // Note that the halfwords are stored high first, low second; so we need
544 // to transpose the fixup value here to map properly.
545 if (Value % 4 != 0) {
546 Ctx.reportError(Fixup.getLoc(), "misaligned ARM call destination");
550 uint32_t offset = (Value - 4) >> 2;
551 if (const MCSymbolRefExpr *SRE =
552 dyn_cast<MCSymbolRefExpr>(Fixup.getValue()))
553 if (SRE->getKind() == MCSymbolRefExpr::VK_TLSCALL)
555 uint32_t signBit = (offset & 0x400000) >> 22;
556 uint32_t I1Bit = (offset & 0x200000) >> 21;
557 uint32_t J1Bit = (I1Bit ^ 0x1) ^ signBit;
558 uint32_t I2Bit = (offset & 0x100000) >> 20;
559 uint32_t J2Bit = (I2Bit ^ 0x1) ^ signBit;
560 uint32_t imm10HBits = (offset & 0xFFC00) >> 10;
561 uint32_t imm10LBits = (offset & 0x3FF);
563 uint32_t FirstHalf = (((uint16_t)signBit << 10) | (uint16_t)imm10HBits);
564 uint32_t SecondHalf = (((uint16_t)J1Bit << 13) | ((uint16_t)J2Bit << 11) |
565 ((uint16_t)imm10LBits) << 1);
566 return joinHalfWords(FirstHalf, SecondHalf, IsLittleEndian);
568 case ARM::fixup_thumb_adr_pcrel_10:
569 case ARM::fixup_arm_thumb_cp:
570 // On CPUs supporting Thumb2, this will be relaxed to an ldr.w, otherwise we
571 // could have an error on our hands.
572 if (!STI->getFeatureBits()[ARM::FeatureThumb2] && IsResolved) {
573 const char *FixupDiagnostic = reasonForFixupRelaxation(Fixup, Value);
574 if (FixupDiagnostic) {
575 Ctx.reportError(Fixup.getLoc(), FixupDiagnostic);
579 // Offset by 4, and don't encode the low two bits.
580 return ((Value - 4) >> 2) & 0xff;
581 case ARM::fixup_arm_thumb_cb: {
582 // CB instructions can only branch to offsets in [4, 126] in multiples of 2
583 // so ensure that the raw value LSB is zero and it lies in [2, 130].
584 // An offset of 2 will be relaxed to a NOP.
585 if ((int64_t)Value < 2 || Value > 0x82 || Value & 1) {
586 Ctx.reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
589 // Offset by 4 and don't encode the lower bit, which is always 0.
590 // FIXME: diagnose if no Thumb2
591 uint32_t Binary = (Value - 4) >> 1;
592 return ((Binary & 0x20) << 4) | ((Binary & 0x1f) << 3);
594 case ARM::fixup_arm_thumb_br:
595 // Offset by 4 and don't encode the lower bit, which is always 0.
596 if (!STI->getFeatureBits()[ARM::FeatureThumb2] &&
597 !STI->getFeatureBits()[ARM::HasV8MBaselineOps]) {
598 const char *FixupDiagnostic = reasonForFixupRelaxation(Fixup, Value);
599 if (FixupDiagnostic) {
600 Ctx.reportError(Fixup.getLoc(), FixupDiagnostic);
604 return ((Value - 4) >> 1) & 0x7ff;
605 case ARM::fixup_arm_thumb_bcc:
606 // Offset by 4 and don't encode the lower bit, which is always 0.
607 if (!STI->getFeatureBits()[ARM::FeatureThumb2]) {
608 const char *FixupDiagnostic = reasonForFixupRelaxation(Fixup, Value);
609 if (FixupDiagnostic) {
610 Ctx.reportError(Fixup.getLoc(), FixupDiagnostic);
614 return ((Value - 4) >> 1) & 0xff;
615 case ARM::fixup_arm_pcrel_10_unscaled: {
616 Value = Value - 8; // ARM fixups offset by an additional word and don't
617 // need to adjust for the half-word ordering.
619 if ((int64_t)Value < 0) {
623 // The value has the low 4 bits encoded in [3:0] and the high 4 in [11:8].
625 Ctx.reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
628 Value = (Value & 0xf) | ((Value & 0xf0) << 4);
629 return Value | (isAdd << 23);
631 case ARM::fixup_arm_pcrel_10:
632 Value = Value - 4; // ARM fixups offset by an additional word and don't
633 // need to adjust for the half-word ordering.
635 case ARM::fixup_t2_pcrel_10: {
636 // Offset by 4, adjusted by two due to the half-word ordering of thumb.
639 if ((int64_t)Value < 0) {
643 // These values don't encode the low two bits since they're always zero.
646 Ctx.reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
649 Value |= isAdd << 23;
651 // Same addressing mode as fixup_arm_pcrel_10, but with 16-bit halfwords
653 if (Kind == ARM::fixup_t2_pcrel_10)
654 return swapHalfWords(Value, IsLittleEndian);
658 case ARM::fixup_arm_pcrel_9:
659 Value = Value - 4; // ARM fixups offset by an additional word and don't
660 // need to adjust for the half-word ordering.
662 case ARM::fixup_t2_pcrel_9: {
663 // Offset by 4, adjusted by two due to the half-word ordering of thumb.
666 if ((int64_t)Value < 0) {
670 // These values don't encode the low bit since it's always zero.
672 Ctx.reportError(Fixup.getLoc(), "invalid value for this fixup");
677 Ctx.reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
680 Value |= isAdd << 23;
682 // Same addressing mode as fixup_arm_pcrel_9, but with 16-bit halfwords
684 if (Kind == ARM::fixup_t2_pcrel_9)
685 return swapHalfWords(Value, IsLittleEndian);
689 case ARM::fixup_arm_mod_imm:
690 Value = ARM_AM::getSOImmVal(Value);
692 Ctx.reportError(Fixup.getLoc(), "out of range immediate fixup value");
699 void ARMAsmBackend::processFixupValue(const MCAssembler &Asm,
700 const MCAsmLayout &Layout,
701 const MCFixup &Fixup,
702 const MCFragment *DF,
703 const MCValue &Target, uint64_t &Value,
705 const MCSymbolRefExpr *A = Target.getSymA();
706 const MCSymbol *Sym = A ? &A->getSymbol() : nullptr;
707 // MachO (the only user of "Value") tries to make .o files that look vaguely
708 // pre-linked, so for MOVW/MOVT and .word relocations they put the Thumb bit
709 // into the addend if possible. Other relocation types don't want this bit
710 // though (branches couldn't encode it if it *was* present, and no other
711 // relocations exist) and it can interfere with checking valid expressions.
712 if ((unsigned)Fixup.getKind() == FK_Data_4 ||
713 (unsigned)Fixup.getKind() == ARM::fixup_arm_movw_lo16 ||
714 (unsigned)Fixup.getKind() == ARM::fixup_arm_movt_hi16 ||
715 (unsigned)Fixup.getKind() == ARM::fixup_t2_movw_lo16 ||
716 (unsigned)Fixup.getKind() == ARM::fixup_t2_movt_hi16) {
718 if (Asm.isThumbFunc(Sym))
722 if (IsResolved && (unsigned)Fixup.getKind() == ARM::fixup_arm_thumb_bl) {
723 assert(Sym && "How did we resolve this?");
725 // If the symbol is external the linker will handle it.
726 // FIXME: Should we handle it as an optimization?
728 // If the symbol is out of range, produce a relocation and hope the
729 // linker can handle it. GNU AS produces an error in this case.
730 if (Sym->isExternal() || Value >= 0x400004)
732 // When an ARM function is called from a Thumb function, produce a
733 // relocation so the linker will use the correct branch instruction for ELF
736 unsigned Type = dyn_cast<MCSymbolELF>(Sym)->getType();
737 if ((Type == ELF::STT_FUNC || Type == ELF::STT_GNU_IFUNC) &&
738 !Asm.isThumbFunc(Sym))
742 // We must always generate a relocation for BL/BLX instructions if we have
743 // a symbol to reference, as the linker relies on knowing the destination
744 // symbol's thumb-ness to get interworking right.
745 if (A && ((unsigned)Fixup.getKind() == ARM::fixup_arm_thumb_blx ||
746 (unsigned)Fixup.getKind() == ARM::fixup_arm_blx ||
747 (unsigned)Fixup.getKind() == ARM::fixup_arm_uncondbl ||
748 (unsigned)Fixup.getKind() == ARM::fixup_arm_condbl))
752 /// getFixupKindNumBytes - The number of bytes the fixup may change.
753 static unsigned getFixupKindNumBytes(unsigned Kind) {
756 llvm_unreachable("Unknown fixup kind!");
759 case ARM::fixup_arm_thumb_bcc:
760 case ARM::fixup_arm_thumb_cp:
761 case ARM::fixup_thumb_adr_pcrel_10:
765 case ARM::fixup_arm_thumb_br:
766 case ARM::fixup_arm_thumb_cb:
767 case ARM::fixup_arm_mod_imm:
770 case ARM::fixup_arm_pcrel_10_unscaled:
771 case ARM::fixup_arm_ldst_pcrel_12:
772 case ARM::fixup_arm_pcrel_10:
773 case ARM::fixup_arm_pcrel_9:
774 case ARM::fixup_arm_adr_pcrel_12:
775 case ARM::fixup_arm_uncondbl:
776 case ARM::fixup_arm_condbl:
777 case ARM::fixup_arm_blx:
778 case ARM::fixup_arm_condbranch:
779 case ARM::fixup_arm_uncondbranch:
783 case ARM::fixup_t2_ldst_pcrel_12:
784 case ARM::fixup_t2_condbranch:
785 case ARM::fixup_t2_uncondbranch:
786 case ARM::fixup_t2_pcrel_10:
787 case ARM::fixup_t2_pcrel_9:
788 case ARM::fixup_t2_adr_pcrel_12:
789 case ARM::fixup_arm_thumb_bl:
790 case ARM::fixup_arm_thumb_blx:
791 case ARM::fixup_arm_movt_hi16:
792 case ARM::fixup_arm_movw_lo16:
793 case ARM::fixup_t2_movt_hi16:
794 case ARM::fixup_t2_movw_lo16:
804 /// getFixupKindContainerSizeBytes - The number of bytes of the
805 /// container involved in big endian.
806 static unsigned getFixupKindContainerSizeBytes(unsigned Kind) {
809 llvm_unreachable("Unknown fixup kind!");
818 case ARM::fixup_arm_thumb_bcc:
819 case ARM::fixup_arm_thumb_cp:
820 case ARM::fixup_thumb_adr_pcrel_10:
821 case ARM::fixup_arm_thumb_br:
822 case ARM::fixup_arm_thumb_cb:
823 // Instruction size is 2 bytes.
826 case ARM::fixup_arm_pcrel_10_unscaled:
827 case ARM::fixup_arm_ldst_pcrel_12:
828 case ARM::fixup_arm_pcrel_10:
829 case ARM::fixup_arm_adr_pcrel_12:
830 case ARM::fixup_arm_uncondbl:
831 case ARM::fixup_arm_condbl:
832 case ARM::fixup_arm_blx:
833 case ARM::fixup_arm_condbranch:
834 case ARM::fixup_arm_uncondbranch:
835 case ARM::fixup_t2_ldst_pcrel_12:
836 case ARM::fixup_t2_condbranch:
837 case ARM::fixup_t2_uncondbranch:
838 case ARM::fixup_t2_pcrel_10:
839 case ARM::fixup_t2_adr_pcrel_12:
840 case ARM::fixup_arm_thumb_bl:
841 case ARM::fixup_arm_thumb_blx:
842 case ARM::fixup_arm_movt_hi16:
843 case ARM::fixup_arm_movw_lo16:
844 case ARM::fixup_t2_movt_hi16:
845 case ARM::fixup_t2_movw_lo16:
846 case ARM::fixup_arm_mod_imm:
847 // Instruction size is 4 bytes.
852 void ARMAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
853 unsigned DataSize, uint64_t Value, bool IsPCRel,
854 MCContext &Ctx) const {
855 unsigned NumBytes = getFixupKindNumBytes(Fixup.getKind());
856 Value = adjustFixupValue(Fixup, Value, IsPCRel, Ctx, IsLittleEndian, true);
858 return; // Doesn't change encoding.
860 unsigned Offset = Fixup.getOffset();
861 assert(Offset + NumBytes <= DataSize && "Invalid fixup offset!");
863 // Used to point to big endian bytes.
864 unsigned FullSizeBytes;
865 if (!IsLittleEndian) {
866 FullSizeBytes = getFixupKindContainerSizeBytes(Fixup.getKind());
867 assert((Offset + FullSizeBytes) <= DataSize && "Invalid fixup size!");
868 assert(NumBytes <= FullSizeBytes && "Invalid fixup size!");
871 // For each byte of the fragment that the fixup touches, mask in the bits from
872 // the fixup value. The Value has been "split up" into the appropriate
874 for (unsigned i = 0; i != NumBytes; ++i) {
875 unsigned Idx = IsLittleEndian ? i : (FullSizeBytes - 1 - i);
876 Data[Offset + Idx] |= uint8_t((Value >> (i * 8)) & 0xff);
882 /// \brief Compact unwind encoding values.
883 enum CompactUnwindEncodings {
884 UNWIND_ARM_MODE_MASK = 0x0F000000,
885 UNWIND_ARM_MODE_FRAME = 0x01000000,
886 UNWIND_ARM_MODE_FRAME_D = 0x02000000,
887 UNWIND_ARM_MODE_DWARF = 0x04000000,
889 UNWIND_ARM_FRAME_STACK_ADJUST_MASK = 0x00C00000,
891 UNWIND_ARM_FRAME_FIRST_PUSH_R4 = 0x00000001,
892 UNWIND_ARM_FRAME_FIRST_PUSH_R5 = 0x00000002,
893 UNWIND_ARM_FRAME_FIRST_PUSH_R6 = 0x00000004,
895 UNWIND_ARM_FRAME_SECOND_PUSH_R8 = 0x00000008,
896 UNWIND_ARM_FRAME_SECOND_PUSH_R9 = 0x00000010,
897 UNWIND_ARM_FRAME_SECOND_PUSH_R10 = 0x00000020,
898 UNWIND_ARM_FRAME_SECOND_PUSH_R11 = 0x00000040,
899 UNWIND_ARM_FRAME_SECOND_PUSH_R12 = 0x00000080,
901 UNWIND_ARM_FRAME_D_REG_COUNT_MASK = 0x00000F00,
903 UNWIND_ARM_DWARF_SECTION_OFFSET = 0x00FFFFFF
906 } // end CU namespace
908 /// Generate compact unwind encoding for the function based on the CFI
909 /// instructions. If the CFI instructions describe a frame that cannot be
910 /// encoded in compact unwind, the method returns UNWIND_ARM_MODE_DWARF which
911 /// tells the runtime to fallback and unwind using dwarf.
912 uint32_t ARMAsmBackendDarwin::generateCompactUnwindEncoding(
913 ArrayRef<MCCFIInstruction> Instrs) const {
914 DEBUG_WITH_TYPE("compact-unwind", llvm::dbgs() << "generateCU()\n");
915 // Only armv7k uses CFI based unwinding.
916 if (Subtype != MachO::CPU_SUBTYPE_ARM_V7K)
918 // No .cfi directives means no frame.
921 // Start off assuming CFA is at SP+0.
922 int CFARegister = ARM::SP;
923 int CFARegisterOffset = 0;
924 // Mark savable registers as initially unsaved
925 DenseMap<unsigned, int> RegOffsets;
926 int FloatRegCount = 0;
927 // Process each .cfi directive and build up compact unwind info.
928 for (size_t i = 0, e = Instrs.size(); i != e; ++i) {
930 const MCCFIInstruction &Inst = Instrs[i];
931 switch (Inst.getOperation()) {
932 case MCCFIInstruction::OpDefCfa: // DW_CFA_def_cfa
933 CFARegisterOffset = -Inst.getOffset();
934 CFARegister = MRI.getLLVMRegNum(Inst.getRegister(), true);
936 case MCCFIInstruction::OpDefCfaOffset: // DW_CFA_def_cfa_offset
937 CFARegisterOffset = -Inst.getOffset();
939 case MCCFIInstruction::OpDefCfaRegister: // DW_CFA_def_cfa_register
940 CFARegister = MRI.getLLVMRegNum(Inst.getRegister(), true);
942 case MCCFIInstruction::OpOffset: // DW_CFA_offset
943 Reg = MRI.getLLVMRegNum(Inst.getRegister(), true);
944 if (ARMMCRegisterClasses[ARM::GPRRegClassID].contains(Reg))
945 RegOffsets[Reg] = Inst.getOffset();
946 else if (ARMMCRegisterClasses[ARM::DPRRegClassID].contains(Reg)) {
947 RegOffsets[Reg] = Inst.getOffset();
950 DEBUG_WITH_TYPE("compact-unwind",
951 llvm::dbgs() << ".cfi_offset on unknown register="
952 << Inst.getRegister() << "\n");
953 return CU::UNWIND_ARM_MODE_DWARF;
956 case MCCFIInstruction::OpRelOffset: // DW_CFA_advance_loc
960 // Directive not convertable to compact unwind, bail out.
961 DEBUG_WITH_TYPE("compact-unwind",
963 << "CFI directive not compatiable with comact "
964 "unwind encoding, opcode=" << Inst.getOperation()
966 return CU::UNWIND_ARM_MODE_DWARF;
971 // If no frame set up, return no unwind info.
972 if ((CFARegister == ARM::SP) && (CFARegisterOffset == 0))
975 // Verify standard frame (lr/r7) was used.
976 if (CFARegister != ARM::R7) {
977 DEBUG_WITH_TYPE("compact-unwind", llvm::dbgs() << "frame register is "
979 << " instead of r7\n");
980 return CU::UNWIND_ARM_MODE_DWARF;
982 int StackAdjust = CFARegisterOffset - 8;
983 if (RegOffsets.lookup(ARM::LR) != (-4 - StackAdjust)) {
984 DEBUG_WITH_TYPE("compact-unwind",
986 << "LR not saved as standard frame, StackAdjust="
988 << ", CFARegisterOffset=" << CFARegisterOffset
989 << ", lr save at offset=" << RegOffsets[14] << "\n");
990 return CU::UNWIND_ARM_MODE_DWARF;
992 if (RegOffsets.lookup(ARM::R7) != (-8 - StackAdjust)) {
993 DEBUG_WITH_TYPE("compact-unwind",
994 llvm::dbgs() << "r7 not saved as standard frame\n");
995 return CU::UNWIND_ARM_MODE_DWARF;
997 uint32_t CompactUnwindEncoding = CU::UNWIND_ARM_MODE_FRAME;
999 // If var-args are used, there may be a stack adjust required.
1000 switch (StackAdjust) {
1004 CompactUnwindEncoding |= 0x00400000;
1007 CompactUnwindEncoding |= 0x00800000;
1010 CompactUnwindEncoding |= 0x00C00000;
1013 DEBUG_WITH_TYPE("compact-unwind", llvm::dbgs()
1014 << ".cfi_def_cfa stack adjust ("
1015 << StackAdjust << ") out of range\n");
1016 return CU::UNWIND_ARM_MODE_DWARF;
1019 // If r6 is saved, it must be right below r7.
1023 } GPRCSRegs[] = {{ARM::R6, CU::UNWIND_ARM_FRAME_FIRST_PUSH_R6},
1024 {ARM::R5, CU::UNWIND_ARM_FRAME_FIRST_PUSH_R5},
1025 {ARM::R4, CU::UNWIND_ARM_FRAME_FIRST_PUSH_R4},
1026 {ARM::R12, CU::UNWIND_ARM_FRAME_SECOND_PUSH_R12},
1027 {ARM::R11, CU::UNWIND_ARM_FRAME_SECOND_PUSH_R11},
1028 {ARM::R10, CU::UNWIND_ARM_FRAME_SECOND_PUSH_R10},
1029 {ARM::R9, CU::UNWIND_ARM_FRAME_SECOND_PUSH_R9},
1030 {ARM::R8, CU::UNWIND_ARM_FRAME_SECOND_PUSH_R8}};
1032 int CurOffset = -8 - StackAdjust;
1033 for (auto CSReg : GPRCSRegs) {
1034 auto Offset = RegOffsets.find(CSReg.Reg);
1035 if (Offset == RegOffsets.end())
1038 int RegOffset = Offset->second;
1039 if (RegOffset != CurOffset - 4) {
1040 DEBUG_WITH_TYPE("compact-unwind",
1041 llvm::dbgs() << MRI.getName(CSReg.Reg) << " saved at "
1042 << RegOffset << " but only supported at "
1043 << CurOffset << "\n");
1044 return CU::UNWIND_ARM_MODE_DWARF;
1046 CompactUnwindEncoding |= CSReg.Encoding;
1050 // If no floats saved, we are done.
1051 if (FloatRegCount == 0)
1052 return CompactUnwindEncoding;
1054 // Switch mode to include D register saving.
1055 CompactUnwindEncoding &= ~CU::UNWIND_ARM_MODE_MASK;
1056 CompactUnwindEncoding |= CU::UNWIND_ARM_MODE_FRAME_D;
1058 // FIXME: supporting more than 4 saved D-registers compactly would be trivial,
1059 // but needs coordination with the linker and libunwind.
1060 if (FloatRegCount > 4) {
1061 DEBUG_WITH_TYPE("compact-unwind",
1062 llvm::dbgs() << "unsupported number of D registers saved ("
1063 << FloatRegCount << ")\n");
1064 return CU::UNWIND_ARM_MODE_DWARF;
1067 // Floating point registers must either be saved sequentially, or we defer to
1068 // DWARF. No gaps allowed here so check that each saved d-register is
1069 // precisely where it should be.
1070 static unsigned FPRCSRegs[] = { ARM::D8, ARM::D10, ARM::D12, ARM::D14 };
1071 for (int Idx = FloatRegCount - 1; Idx >= 0; --Idx) {
1072 auto Offset = RegOffsets.find(FPRCSRegs[Idx]);
1073 if (Offset == RegOffsets.end()) {
1074 DEBUG_WITH_TYPE("compact-unwind",
1075 llvm::dbgs() << FloatRegCount << " D-regs saved, but "
1076 << MRI.getName(FPRCSRegs[Idx])
1078 return CU::UNWIND_ARM_MODE_DWARF;
1079 } else if (Offset->second != CurOffset - 8) {
1080 DEBUG_WITH_TYPE("compact-unwind",
1081 llvm::dbgs() << FloatRegCount << " D-regs saved, but "
1082 << MRI.getName(FPRCSRegs[Idx])
1083 << " saved at " << Offset->second
1084 << ", expected at " << CurOffset - 8
1086 return CU::UNWIND_ARM_MODE_DWARF;
1091 return CompactUnwindEncoding | ((FloatRegCount - 1) << 8);
1094 static MachO::CPUSubTypeARM getMachOSubTypeFromArch(StringRef Arch) {
1095 unsigned AK = ARM::parseArch(Arch);
1098 return MachO::CPU_SUBTYPE_ARM_V7;
1099 case ARM::AK_ARMV4T:
1100 return MachO::CPU_SUBTYPE_ARM_V4T;
1101 case ARM::AK_ARMV5T:
1102 case ARM::AK_ARMV5TE:
1103 case ARM::AK_ARMV5TEJ:
1104 return MachO::CPU_SUBTYPE_ARM_V5;
1106 case ARM::AK_ARMV6K:
1107 return MachO::CPU_SUBTYPE_ARM_V6;
1108 case ARM::AK_ARMV7A:
1109 return MachO::CPU_SUBTYPE_ARM_V7;
1110 case ARM::AK_ARMV7S:
1111 return MachO::CPU_SUBTYPE_ARM_V7S;
1112 case ARM::AK_ARMV7K:
1113 return MachO::CPU_SUBTYPE_ARM_V7K;
1114 case ARM::AK_ARMV6M:
1115 return MachO::CPU_SUBTYPE_ARM_V6M;
1116 case ARM::AK_ARMV7M:
1117 return MachO::CPU_SUBTYPE_ARM_V7M;
1118 case ARM::AK_ARMV7EM:
1119 return MachO::CPU_SUBTYPE_ARM_V7EM;
1123 MCAsmBackend *llvm::createARMAsmBackend(const Target &T,
1124 const MCRegisterInfo &MRI,
1125 const Triple &TheTriple, StringRef CPU,
1126 const MCTargetOptions &Options,
1128 switch (TheTriple.getObjectFormat()) {
1130 llvm_unreachable("unsupported object format");
1131 case Triple::MachO: {
1132 MachO::CPUSubTypeARM CS = getMachOSubTypeFromArch(TheTriple.getArchName());
1133 return new ARMAsmBackendDarwin(T, TheTriple, MRI, CS);
1136 assert(TheTriple.isOSWindows() && "non-Windows ARM COFF is not supported");
1137 return new ARMAsmBackendWinCOFF(T, TheTriple);
1139 assert(TheTriple.isOSBinFormatELF() && "using ELF for non-ELF target");
1140 uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TheTriple.getOS());
1141 return new ARMAsmBackendELF(T, TheTriple, OSABI, isLittle);
1145 MCAsmBackend *llvm::createARMLEAsmBackend(const Target &T,
1146 const MCRegisterInfo &MRI,
1147 const Triple &TT, StringRef CPU,
1148 const MCTargetOptions &Options) {
1149 return createARMAsmBackend(T, MRI, TT, CPU, Options, true);
1152 MCAsmBackend *llvm::createARMBEAsmBackend(const Target &T,
1153 const MCRegisterInfo &MRI,
1154 const Triple &TT, StringRef CPU,
1155 const MCTargetOptions &Options) {
1156 return createARMAsmBackend(T, MRI, TT, CPU, Options, false);
1159 MCAsmBackend *llvm::createThumbLEAsmBackend(const Target &T,
1160 const MCRegisterInfo &MRI,
1161 const Triple &TT, StringRef CPU,
1162 const MCTargetOptions &Options) {
1163 return createARMAsmBackend(T, MRI, TT, CPU, Options, true);
1166 MCAsmBackend *llvm::createThumbBEAsmBackend(const Target &T,
1167 const MCRegisterInfo &MRI,
1168 const Triple &TT, StringRef CPU,
1169 const MCTargetOptions &Options) {
1170 return createARMAsmBackend(T, MRI, TT, CPU, Options, false);