1 //===--- X86InstPrinterCommon.cpp - X86 assembly instruction printing -----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file includes common code for rendering MCInst instances as Intel-style
10 // and Intel-style assembly.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "X86InstPrinterCommon.h"
15 #include "X86BaseInfo.h"
16 #include "llvm/MC/MCAsmInfo.h"
17 #include "llvm/MC/MCExpr.h"
18 #include "llvm/MC/MCInst.h"
19 #include "llvm/MC/MCInstrDesc.h"
20 #include "llvm/MC/MCInstrInfo.h"
21 #include "llvm/MC/MCSubtargetInfo.h"
22 #include "llvm/Support/Casting.h"
23 #include "llvm/Support/raw_ostream.h"
24 #include <cassert>
25 #include <cstdint>
26
27 using namespace llvm;
28
printCondCode(const MCInst * MI,unsigned Op,raw_ostream & O)29 void X86InstPrinterCommon::printCondCode(const MCInst *MI, unsigned Op,
30 raw_ostream &O) {
31 int64_t Imm = MI->getOperand(Op).getImm();
32 unsigned Opc = MI->getOpcode();
33 bool IsCMPCCXADD = X86::isCMPCCXADD(Opc);
34 bool IsCCMPOrCTEST = X86::isCCMPCC(Opc) || X86::isCTESTCC(Opc);
35
36 // clang-format off
37 switch (Imm) {
38 default: llvm_unreachable("Invalid condcode argument!");
39 case 0: O << "o"; break;
40 case 1: O << "no"; break;
41 case 2: O << "b"; break;
42 case 3: O << (IsCMPCCXADD ? "nb" : "ae"); break;
43 case 4: O << (IsCMPCCXADD ? "z" : "e"); break;
44 case 5: O << (IsCMPCCXADD ? "nz" : "ne"); break;
45 case 6: O << "be"; break;
46 case 7: O << (IsCMPCCXADD ? "nbe" : "a"); break;
47 case 8: O << "s"; break;
48 case 9: O << "ns"; break;
49 case 0xa: O << (IsCCMPOrCTEST ? "t" : "p"); break;
50 case 0xb: O << (IsCCMPOrCTEST ? "f" : "np"); break;
51 case 0xc: O << "l"; break;
52 case 0xd: O << (IsCMPCCXADD ? "nl" : "ge"); break;
53 case 0xe: O << "le"; break;
54 case 0xf: O << (IsCMPCCXADD ? "nle" : "g"); break;
55 }
56 // clang-format on
57 }
58
printCondFlags(const MCInst * MI,unsigned Op,raw_ostream & O)59 void X86InstPrinterCommon::printCondFlags(const MCInst *MI, unsigned Op,
60 raw_ostream &O) {
61 // +----+----+----+----+
62 // | OF | SF | ZF | CF |
63 // +----+----+----+----+
64 int64_t Imm = MI->getOperand(Op).getImm();
65 assert(Imm >= 0 && Imm < 16 && "Invalid condition flags");
66 O << "{dfv=";
67 std::string Flags;
68 if (Imm & 0x8)
69 Flags += "of,";
70 if (Imm & 0x4)
71 Flags += "sf,";
72 if (Imm & 0x2)
73 Flags += "zf,";
74 if (Imm & 0x1)
75 Flags += "cf,";
76 StringRef SimplifiedFlags = StringRef(Flags).rtrim(",");
77 O << SimplifiedFlags << "}";
78 }
79
printSSEAVXCC(const MCInst * MI,unsigned Op,raw_ostream & O)80 void X86InstPrinterCommon::printSSEAVXCC(const MCInst *MI, unsigned Op,
81 raw_ostream &O) {
82 int64_t Imm = MI->getOperand(Op).getImm();
83 switch (Imm) {
84 default: llvm_unreachable("Invalid ssecc/avxcc argument!");
85 case 0: O << "eq"; break;
86 case 1: O << "lt"; break;
87 case 2: O << "le"; break;
88 case 3: O << "unord"; break;
89 case 4: O << "neq"; break;
90 case 5: O << "nlt"; break;
91 case 6: O << "nle"; break;
92 case 7: O << "ord"; break;
93 case 8: O << "eq_uq"; break;
94 case 9: O << "nge"; break;
95 case 0xa: O << "ngt"; break;
96 case 0xb: O << "false"; break;
97 case 0xc: O << "neq_oq"; break;
98 case 0xd: O << "ge"; break;
99 case 0xe: O << "gt"; break;
100 case 0xf: O << "true"; break;
101 case 0x10: O << "eq_os"; break;
102 case 0x11: O << "lt_oq"; break;
103 case 0x12: O << "le_oq"; break;
104 case 0x13: O << "unord_s"; break;
105 case 0x14: O << "neq_us"; break;
106 case 0x15: O << "nlt_uq"; break;
107 case 0x16: O << "nle_uq"; break;
108 case 0x17: O << "ord_s"; break;
109 case 0x18: O << "eq_us"; break;
110 case 0x19: O << "nge_uq"; break;
111 case 0x1a: O << "ngt_uq"; break;
112 case 0x1b: O << "false_os"; break;
113 case 0x1c: O << "neq_os"; break;
114 case 0x1d: O << "ge_oq"; break;
115 case 0x1e: O << "gt_oq"; break;
116 case 0x1f: O << "true_us"; break;
117 }
118 }
119
printVPCOMMnemonic(const MCInst * MI,raw_ostream & OS)120 void X86InstPrinterCommon::printVPCOMMnemonic(const MCInst *MI,
121 raw_ostream &OS) {
122 OS << "vpcom";
123
124 int64_t Imm = MI->getOperand(MI->getNumOperands() - 1).getImm();
125 switch (Imm) {
126 default: llvm_unreachable("Invalid vpcom argument!");
127 case 0: OS << "lt"; break;
128 case 1: OS << "le"; break;
129 case 2: OS << "gt"; break;
130 case 3: OS << "ge"; break;
131 case 4: OS << "eq"; break;
132 case 5: OS << "neq"; break;
133 case 6: OS << "false"; break;
134 case 7: OS << "true"; break;
135 }
136
137 switch (MI->getOpcode()) {
138 default: llvm_unreachable("Unexpected opcode!");
139 case X86::VPCOMBmi: case X86::VPCOMBri: OS << "b\t"; break;
140 case X86::VPCOMDmi: case X86::VPCOMDri: OS << "d\t"; break;
141 case X86::VPCOMQmi: case X86::VPCOMQri: OS << "q\t"; break;
142 case X86::VPCOMUBmi: case X86::VPCOMUBri: OS << "ub\t"; break;
143 case X86::VPCOMUDmi: case X86::VPCOMUDri: OS << "ud\t"; break;
144 case X86::VPCOMUQmi: case X86::VPCOMUQri: OS << "uq\t"; break;
145 case X86::VPCOMUWmi: case X86::VPCOMUWri: OS << "uw\t"; break;
146 case X86::VPCOMWmi: case X86::VPCOMWri: OS << "w\t"; break;
147 }
148 }
149
printVPCMPMnemonic(const MCInst * MI,raw_ostream & OS)150 void X86InstPrinterCommon::printVPCMPMnemonic(const MCInst *MI,
151 raw_ostream &OS) {
152 OS << "vpcmp";
153
154 printSSEAVXCC(MI, MI->getNumOperands() - 1, OS);
155
156 switch (MI->getOpcode()) {
157 default: llvm_unreachable("Unexpected opcode!");
158 case X86::VPCMPBZ128rmi: case X86::VPCMPBZ128rri:
159 case X86::VPCMPBZ256rmi: case X86::VPCMPBZ256rri:
160 case X86::VPCMPBZrmi: case X86::VPCMPBZrri:
161 case X86::VPCMPBZ128rmik: case X86::VPCMPBZ128rrik:
162 case X86::VPCMPBZ256rmik: case X86::VPCMPBZ256rrik:
163 case X86::VPCMPBZrmik: case X86::VPCMPBZrrik:
164 OS << "b\t";
165 break;
166 case X86::VPCMPDZ128rmi: case X86::VPCMPDZ128rri:
167 case X86::VPCMPDZ256rmi: case X86::VPCMPDZ256rri:
168 case X86::VPCMPDZrmi: case X86::VPCMPDZrri:
169 case X86::VPCMPDZ128rmik: case X86::VPCMPDZ128rrik:
170 case X86::VPCMPDZ256rmik: case X86::VPCMPDZ256rrik:
171 case X86::VPCMPDZrmik: case X86::VPCMPDZrrik:
172 case X86::VPCMPDZ128rmib: case X86::VPCMPDZ128rmibk:
173 case X86::VPCMPDZ256rmib: case X86::VPCMPDZ256rmibk:
174 case X86::VPCMPDZrmib: case X86::VPCMPDZrmibk:
175 OS << "d\t";
176 break;
177 case X86::VPCMPQZ128rmi: case X86::VPCMPQZ128rri:
178 case X86::VPCMPQZ256rmi: case X86::VPCMPQZ256rri:
179 case X86::VPCMPQZrmi: case X86::VPCMPQZrri:
180 case X86::VPCMPQZ128rmik: case X86::VPCMPQZ128rrik:
181 case X86::VPCMPQZ256rmik: case X86::VPCMPQZ256rrik:
182 case X86::VPCMPQZrmik: case X86::VPCMPQZrrik:
183 case X86::VPCMPQZ128rmib: case X86::VPCMPQZ128rmibk:
184 case X86::VPCMPQZ256rmib: case X86::VPCMPQZ256rmibk:
185 case X86::VPCMPQZrmib: case X86::VPCMPQZrmibk:
186 OS << "q\t";
187 break;
188 case X86::VPCMPUBZ128rmi: case X86::VPCMPUBZ128rri:
189 case X86::VPCMPUBZ256rmi: case X86::VPCMPUBZ256rri:
190 case X86::VPCMPUBZrmi: case X86::VPCMPUBZrri:
191 case X86::VPCMPUBZ128rmik: case X86::VPCMPUBZ128rrik:
192 case X86::VPCMPUBZ256rmik: case X86::VPCMPUBZ256rrik:
193 case X86::VPCMPUBZrmik: case X86::VPCMPUBZrrik:
194 OS << "ub\t";
195 break;
196 case X86::VPCMPUDZ128rmi: case X86::VPCMPUDZ128rri:
197 case X86::VPCMPUDZ256rmi: case X86::VPCMPUDZ256rri:
198 case X86::VPCMPUDZrmi: case X86::VPCMPUDZrri:
199 case X86::VPCMPUDZ128rmik: case X86::VPCMPUDZ128rrik:
200 case X86::VPCMPUDZ256rmik: case X86::VPCMPUDZ256rrik:
201 case X86::VPCMPUDZrmik: case X86::VPCMPUDZrrik:
202 case X86::VPCMPUDZ128rmib: case X86::VPCMPUDZ128rmibk:
203 case X86::VPCMPUDZ256rmib: case X86::VPCMPUDZ256rmibk:
204 case X86::VPCMPUDZrmib: case X86::VPCMPUDZrmibk:
205 OS << "ud\t";
206 break;
207 case X86::VPCMPUQZ128rmi: case X86::VPCMPUQZ128rri:
208 case X86::VPCMPUQZ256rmi: case X86::VPCMPUQZ256rri:
209 case X86::VPCMPUQZrmi: case X86::VPCMPUQZrri:
210 case X86::VPCMPUQZ128rmik: case X86::VPCMPUQZ128rrik:
211 case X86::VPCMPUQZ256rmik: case X86::VPCMPUQZ256rrik:
212 case X86::VPCMPUQZrmik: case X86::VPCMPUQZrrik:
213 case X86::VPCMPUQZ128rmib: case X86::VPCMPUQZ128rmibk:
214 case X86::VPCMPUQZ256rmib: case X86::VPCMPUQZ256rmibk:
215 case X86::VPCMPUQZrmib: case X86::VPCMPUQZrmibk:
216 OS << "uq\t";
217 break;
218 case X86::VPCMPUWZ128rmi: case X86::VPCMPUWZ128rri:
219 case X86::VPCMPUWZ256rri: case X86::VPCMPUWZ256rmi:
220 case X86::VPCMPUWZrmi: case X86::VPCMPUWZrri:
221 case X86::VPCMPUWZ128rmik: case X86::VPCMPUWZ128rrik:
222 case X86::VPCMPUWZ256rrik: case X86::VPCMPUWZ256rmik:
223 case X86::VPCMPUWZrmik: case X86::VPCMPUWZrrik:
224 OS << "uw\t";
225 break;
226 case X86::VPCMPWZ128rmi: case X86::VPCMPWZ128rri:
227 case X86::VPCMPWZ256rmi: case X86::VPCMPWZ256rri:
228 case X86::VPCMPWZrmi: case X86::VPCMPWZrri:
229 case X86::VPCMPWZ128rmik: case X86::VPCMPWZ128rrik:
230 case X86::VPCMPWZ256rmik: case X86::VPCMPWZ256rrik:
231 case X86::VPCMPWZrmik: case X86::VPCMPWZrrik:
232 OS << "w\t";
233 break;
234 }
235 }
236
printCMPMnemonic(const MCInst * MI,bool IsVCmp,raw_ostream & OS)237 void X86InstPrinterCommon::printCMPMnemonic(const MCInst *MI, bool IsVCmp,
238 raw_ostream &OS) {
239 OS << (IsVCmp ? "vcmp" : "cmp");
240
241 printSSEAVXCC(MI, MI->getNumOperands() - 1, OS);
242
243 switch (MI->getOpcode()) {
244 default: llvm_unreachable("Unexpected opcode!");
245 case X86::CMPPDrmi: case X86::CMPPDrri:
246 case X86::VCMPPDrmi: case X86::VCMPPDrri:
247 case X86::VCMPPDYrmi: case X86::VCMPPDYrri:
248 case X86::VCMPPDZ128rmi: case X86::VCMPPDZ128rri:
249 case X86::VCMPPDZ256rmi: case X86::VCMPPDZ256rri:
250 case X86::VCMPPDZrmi: case X86::VCMPPDZrri:
251 case X86::VCMPPDZ128rmik: case X86::VCMPPDZ128rrik:
252 case X86::VCMPPDZ256rmik: case X86::VCMPPDZ256rrik:
253 case X86::VCMPPDZrmik: case X86::VCMPPDZrrik:
254 case X86::VCMPPDZ128rmbi: case X86::VCMPPDZ128rmbik:
255 case X86::VCMPPDZ256rmbi: case X86::VCMPPDZ256rmbik:
256 case X86::VCMPPDZrmbi: case X86::VCMPPDZrmbik:
257 case X86::VCMPPDZrrib: case X86::VCMPPDZrribk:
258 OS << "pd\t";
259 break;
260 case X86::CMPPSrmi: case X86::CMPPSrri:
261 case X86::VCMPPSrmi: case X86::VCMPPSrri:
262 case X86::VCMPPSYrmi: case X86::VCMPPSYrri:
263 case X86::VCMPPSZ128rmi: case X86::VCMPPSZ128rri:
264 case X86::VCMPPSZ256rmi: case X86::VCMPPSZ256rri:
265 case X86::VCMPPSZrmi: case X86::VCMPPSZrri:
266 case X86::VCMPPSZ128rmik: case X86::VCMPPSZ128rrik:
267 case X86::VCMPPSZ256rmik: case X86::VCMPPSZ256rrik:
268 case X86::VCMPPSZrmik: case X86::VCMPPSZrrik:
269 case X86::VCMPPSZ128rmbi: case X86::VCMPPSZ128rmbik:
270 case X86::VCMPPSZ256rmbi: case X86::VCMPPSZ256rmbik:
271 case X86::VCMPPSZrmbi: case X86::VCMPPSZrmbik:
272 case X86::VCMPPSZrrib: case X86::VCMPPSZrribk:
273 OS << "ps\t";
274 break;
275 case X86::CMPSDrmi: case X86::CMPSDrri:
276 case X86::CMPSDrmi_Int: case X86::CMPSDrri_Int:
277 case X86::VCMPSDrmi: case X86::VCMPSDrri:
278 case X86::VCMPSDrmi_Int: case X86::VCMPSDrri_Int:
279 case X86::VCMPSDZrmi: case X86::VCMPSDZrri:
280 case X86::VCMPSDZrmi_Int: case X86::VCMPSDZrri_Int:
281 case X86::VCMPSDZrmi_Intk: case X86::VCMPSDZrri_Intk:
282 case X86::VCMPSDZrrib_Int: case X86::VCMPSDZrrib_Intk:
283 OS << "sd\t";
284 break;
285 case X86::CMPSSrmi: case X86::CMPSSrri:
286 case X86::CMPSSrmi_Int: case X86::CMPSSrri_Int:
287 case X86::VCMPSSrmi: case X86::VCMPSSrri:
288 case X86::VCMPSSrmi_Int: case X86::VCMPSSrri_Int:
289 case X86::VCMPSSZrmi: case X86::VCMPSSZrri:
290 case X86::VCMPSSZrmi_Int: case X86::VCMPSSZrri_Int:
291 case X86::VCMPSSZrmi_Intk: case X86::VCMPSSZrri_Intk:
292 case X86::VCMPSSZrrib_Int: case X86::VCMPSSZrrib_Intk:
293 OS << "ss\t";
294 break;
295 case X86::VCMPPHZ128rmi: case X86::VCMPPHZ128rri:
296 case X86::VCMPPHZ256rmi: case X86::VCMPPHZ256rri:
297 case X86::VCMPPHZrmi: case X86::VCMPPHZrri:
298 case X86::VCMPPHZ128rmik: case X86::VCMPPHZ128rrik:
299 case X86::VCMPPHZ256rmik: case X86::VCMPPHZ256rrik:
300 case X86::VCMPPHZrmik: case X86::VCMPPHZrrik:
301 case X86::VCMPPHZ128rmbi: case X86::VCMPPHZ128rmbik:
302 case X86::VCMPPHZ256rmbi: case X86::VCMPPHZ256rmbik:
303 case X86::VCMPPHZrmbi: case X86::VCMPPHZrmbik:
304 case X86::VCMPPHZrrib: case X86::VCMPPHZrribk:
305 OS << "ph\t";
306 break;
307 case X86::VCMPSHZrmi: case X86::VCMPSHZrri:
308 case X86::VCMPSHZrmi_Int: case X86::VCMPSHZrri_Int:
309 case X86::VCMPSHZrrib_Int: case X86::VCMPSHZrrib_Intk:
310 case X86::VCMPSHZrmi_Intk: case X86::VCMPSHZrri_Intk:
311 OS << "sh\t";
312 break;
313 }
314 }
315
printRoundingControl(const MCInst * MI,unsigned Op,raw_ostream & O)316 void X86InstPrinterCommon::printRoundingControl(const MCInst *MI, unsigned Op,
317 raw_ostream &O) {
318 int64_t Imm = MI->getOperand(Op).getImm();
319 switch (Imm) {
320 default:
321 llvm_unreachable("Invalid rounding control!");
322 case X86::TO_NEAREST_INT:
323 O << "{rn-sae}";
324 break;
325 case X86::TO_NEG_INF:
326 O << "{rd-sae}";
327 break;
328 case X86::TO_POS_INF:
329 O << "{ru-sae}";
330 break;
331 case X86::TO_ZERO:
332 O << "{rz-sae}";
333 break;
334 }
335 }
336
337 /// value (e.g. for jumps and calls). In Intel-style these print slightly
338 /// differently than normal immediates. For example, a $ is not emitted.
339 ///
340 /// \p Address The address of the next instruction.
341 /// \see MCInstPrinter::printInst
printPCRelImm(const MCInst * MI,uint64_t Address,unsigned OpNo,raw_ostream & O)342 void X86InstPrinterCommon::printPCRelImm(const MCInst *MI, uint64_t Address,
343 unsigned OpNo, raw_ostream &O) {
344 // Do not print the numberic target address when symbolizing.
345 if (SymbolizeOperands)
346 return;
347
348 const MCOperand &Op = MI->getOperand(OpNo);
349 if (Op.isImm()) {
350 if (PrintBranchImmAsAddress) {
351 uint64_t Target = Address + Op.getImm();
352 if (MAI.getCodePointerSize() == 4)
353 Target &= 0xffffffff;
354 markup(O, Markup::Target) << formatHex(Target);
355 } else
356 markup(O, Markup::Immediate) << formatImm(Op.getImm());
357 } else {
358 assert(Op.isExpr() && "unknown pcrel immediate operand");
359 // If a symbolic branch target was added as a constant expression then print
360 // that address in hex.
361 const MCConstantExpr *BranchTarget = dyn_cast<MCConstantExpr>(Op.getExpr());
362 int64_t Address;
363 if (BranchTarget && BranchTarget->evaluateAsAbsolute(Address)) {
364 markup(O, Markup::Immediate) << formatHex((uint64_t)Address);
365 } else {
366 // Otherwise, just print the expression.
367 Op.getExpr()->print(O, &MAI);
368 }
369 }
370 }
371
printOptionalSegReg(const MCInst * MI,unsigned OpNo,raw_ostream & O)372 void X86InstPrinterCommon::printOptionalSegReg(const MCInst *MI, unsigned OpNo,
373 raw_ostream &O) {
374 if (MI->getOperand(OpNo).getReg()) {
375 printOperand(MI, OpNo, O);
376 O << ':';
377 }
378 }
379
printInstFlags(const MCInst * MI,raw_ostream & O,const MCSubtargetInfo & STI)380 void X86InstPrinterCommon::printInstFlags(const MCInst *MI, raw_ostream &O,
381 const MCSubtargetInfo &STI) {
382 const MCInstrDesc &Desc = MII.get(MI->getOpcode());
383 uint64_t TSFlags = Desc.TSFlags;
384 unsigned Flags = MI->getFlags();
385
386 if ((TSFlags & X86II::LOCK) || (Flags & X86::IP_HAS_LOCK))
387 O << "\tlock\t";
388
389 if ((TSFlags & X86II::NOTRACK) || (Flags & X86::IP_HAS_NOTRACK))
390 O << "\tnotrack\t";
391
392 if (Flags & X86::IP_HAS_REPEAT_NE)
393 O << "\trepne\t";
394 else if (Flags & X86::IP_HAS_REPEAT)
395 O << "\trep\t";
396
397 if (TSFlags & X86II::EVEX_NF && !X86::isCFCMOVCC(MI->getOpcode()))
398 O << "\t{nf}";
399
400 // These all require a pseudo prefix
401 if ((Flags & X86::IP_USE_VEX) ||
402 (TSFlags & X86II::ExplicitOpPrefixMask) == X86II::ExplicitVEXPrefix)
403 O << "\t{vex}";
404 else if (Flags & X86::IP_USE_VEX2)
405 O << "\t{vex2}";
406 else if (Flags & X86::IP_USE_VEX3)
407 O << "\t{vex3}";
408 else if ((Flags & X86::IP_USE_EVEX) ||
409 (TSFlags & X86II::ExplicitOpPrefixMask) == X86II::ExplicitEVEXPrefix)
410 O << "\t{evex}";
411
412 if (Flags & X86::IP_USE_DISP8)
413 O << "\t{disp8}";
414 else if (Flags & X86::IP_USE_DISP32)
415 O << "\t{disp32}";
416
417 // Determine where the memory operand starts, if present
418 int MemoryOperand = X86II::getMemoryOperandNo(TSFlags);
419 if (MemoryOperand != -1)
420 MemoryOperand += X86II::getOperandBias(Desc);
421
422 // Address-Size override prefix
423 if (Flags & X86::IP_HAS_AD_SIZE &&
424 !X86_MC::needsAddressSizeOverride(*MI, STI, MemoryOperand, TSFlags)) {
425 if (STI.hasFeature(X86::Is16Bit) || STI.hasFeature(X86::Is64Bit))
426 O << "\taddr32\t";
427 else if (STI.hasFeature(X86::Is32Bit))
428 O << "\taddr16\t";
429 }
430 }
431
printVKPair(const MCInst * MI,unsigned OpNo,raw_ostream & OS)432 void X86InstPrinterCommon::printVKPair(const MCInst *MI, unsigned OpNo,
433 raw_ostream &OS) {
434 // In assembly listings, a pair is represented by one of its members, any
435 // of the two. Here, we pick k0, k2, k4, k6, but we could as well
436 // print K2_K3 as "k3". It would probably make a lot more sense, if
437 // the assembly would look something like:
438 // "vp2intersect %zmm5, %zmm7, {%k2, %k3}"
439 // but this can work too.
440 switch (MI->getOperand(OpNo).getReg()) {
441 case X86::K0_K1:
442 printRegName(OS, X86::K0);
443 return;
444 case X86::K2_K3:
445 printRegName(OS, X86::K2);
446 return;
447 case X86::K4_K5:
448 printRegName(OS, X86::K4);
449 return;
450 case X86::K6_K7:
451 printRegName(OS, X86::K6);
452 return;
453 }
454 llvm_unreachable("Unknown mask pair register name");
455 }
456