1 //===- X86RegisterInfo.td - Describe the X86 Register File --*- tablegen -*-==//
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
7 //===----------------------------------------------------------------------===//
9 // This file describes the X86 Register file, defining the registers themselves,
10 // aliases between the registers, and the register classes built out of the
13 //===----------------------------------------------------------------------===//
15 class X86Reg<string n, bits<16> Enc, list<Register> subregs = []> : Register<n> {
16 let Namespace = "X86";
18 let SubRegs = subregs;
21 // Subregister indices.
22 let Namespace = "X86" in {
23 def sub_8bit : SubRegIndex<8>;
24 def sub_8bit_hi : SubRegIndex<8, 8>;
25 def sub_8bit_hi_phony : SubRegIndex<8, 8>;
26 def sub_16bit : SubRegIndex<16>;
27 def sub_16bit_hi : SubRegIndex<16, 16>;
28 def sub_32bit : SubRegIndex<32>;
29 def sub_xmm : SubRegIndex<128>;
30 def sub_ymm : SubRegIndex<256>;
31 def sub_mask_0 : SubRegIndex<-1>;
32 def sub_mask_1 : SubRegIndex<-1, -1>;
35 //===----------------------------------------------------------------------===//
36 // Register definitions...
39 // In the register alias definitions below, we define which registers alias
40 // which others. We only specify which registers the small registers alias,
41 // because the register file generator is smart enough to figure out that
42 // AL aliases AX if we tell it that AX aliased AL (for example).
44 // Dwarf numbering is different for 32-bit and 64-bit, and there are
45 // variations by target as well. Currently the first entry is for X86-64,
46 // second - for EH on X86-32/Darwin and third is 'generic' one (X86-32/Linux
47 // and debug information on X86-32/Darwin)
51 def AL : X86Reg<"al", 0>;
52 def DL : X86Reg<"dl", 2>;
53 def CL : X86Reg<"cl", 1>;
54 def BL : X86Reg<"bl", 3>;
56 // High registers. On x86-64, these cannot be used in any instruction
58 def AH : X86Reg<"ah", 4>;
59 def DH : X86Reg<"dh", 6>;
60 def CH : X86Reg<"ch", 5>;
61 def BH : X86Reg<"bh", 7>;
63 // X86-64 only, requires REX.
64 let CostPerUse = 1 in {
65 def SIL : X86Reg<"sil", 6>;
66 def DIL : X86Reg<"dil", 7>;
67 def BPL : X86Reg<"bpl", 5>;
68 def SPL : X86Reg<"spl", 4>;
69 def R8B : X86Reg<"r8b", 8>;
70 def R9B : X86Reg<"r9b", 9>;
71 def R10B : X86Reg<"r10b", 10>;
72 def R11B : X86Reg<"r11b", 11>;
73 def R12B : X86Reg<"r12b", 12>;
74 def R13B : X86Reg<"r13b", 13>;
75 def R14B : X86Reg<"r14b", 14>;
76 def R15B : X86Reg<"r15b", 15>;
79 let isArtificial = 1 in {
80 // High byte of the low 16 bits of the super-register:
81 def SIH : X86Reg<"", -1>;
82 def DIH : X86Reg<"", -1>;
83 def BPH : X86Reg<"", -1>;
84 def SPH : X86Reg<"", -1>;
85 def R8BH : X86Reg<"", -1>;
86 def R9BH : X86Reg<"", -1>;
87 def R10BH : X86Reg<"", -1>;
88 def R11BH : X86Reg<"", -1>;
89 def R12BH : X86Reg<"", -1>;
90 def R13BH : X86Reg<"", -1>;
91 def R14BH : X86Reg<"", -1>;
92 def R15BH : X86Reg<"", -1>;
93 // High word of the low 32 bits of the super-register:
94 def HAX : X86Reg<"", -1>;
95 def HDX : X86Reg<"", -1>;
96 def HCX : X86Reg<"", -1>;
97 def HBX : X86Reg<"", -1>;
98 def HSI : X86Reg<"", -1>;
99 def HDI : X86Reg<"", -1>;
100 def HBP : X86Reg<"", -1>;
101 def HSP : X86Reg<"", -1>;
102 def HIP : X86Reg<"", -1>;
103 def R8WH : X86Reg<"", -1>;
104 def R9WH : X86Reg<"", -1>;
105 def R10WH : X86Reg<"", -1>;
106 def R11WH : X86Reg<"", -1>;
107 def R12WH : X86Reg<"", -1>;
108 def R13WH : X86Reg<"", -1>;
109 def R14WH : X86Reg<"", -1>;
110 def R15WH : X86Reg<"", -1>;
114 let SubRegIndices = [sub_8bit, sub_8bit_hi], CoveredBySubRegs = 1 in {
115 def AX : X86Reg<"ax", 0, [AL,AH]>;
116 def DX : X86Reg<"dx", 2, [DL,DH]>;
117 def CX : X86Reg<"cx", 1, [CL,CH]>;
118 def BX : X86Reg<"bx", 3, [BL,BH]>;
120 let SubRegIndices = [sub_8bit, sub_8bit_hi_phony], CoveredBySubRegs = 1 in {
121 def SI : X86Reg<"si", 6, [SIL,SIH]>;
122 def DI : X86Reg<"di", 7, [DIL,DIH]>;
123 def BP : X86Reg<"bp", 5, [BPL,BPH]>;
124 def SP : X86Reg<"sp", 4, [SPL,SPH]>;
126 def IP : X86Reg<"ip", 0>;
128 // X86-64 only, requires REX.
129 let SubRegIndices = [sub_8bit, sub_8bit_hi_phony], CostPerUse = 1,
130 CoveredBySubRegs = 1 in {
131 def R8W : X86Reg<"r8w", 8, [R8B,R8BH]>;
132 def R9W : X86Reg<"r9w", 9, [R9B,R9BH]>;
133 def R10W : X86Reg<"r10w", 10, [R10B,R10BH]>;
134 def R11W : X86Reg<"r11w", 11, [R11B,R11BH]>;
135 def R12W : X86Reg<"r12w", 12, [R12B,R12BH]>;
136 def R13W : X86Reg<"r13w", 13, [R13B,R13BH]>;
137 def R14W : X86Reg<"r14w", 14, [R14B,R14BH]>;
138 def R15W : X86Reg<"r15w", 15, [R15B,R15BH]>;
142 let SubRegIndices = [sub_16bit, sub_16bit_hi], CoveredBySubRegs = 1 in {
143 def EAX : X86Reg<"eax", 0, [AX, HAX]>, DwarfRegNum<[-2, 0, 0]>;
144 def EDX : X86Reg<"edx", 2, [DX, HDX]>, DwarfRegNum<[-2, 2, 2]>;
145 def ECX : X86Reg<"ecx", 1, [CX, HCX]>, DwarfRegNum<[-2, 1, 1]>;
146 def EBX : X86Reg<"ebx", 3, [BX, HBX]>, DwarfRegNum<[-2, 3, 3]>;
147 def ESI : X86Reg<"esi", 6, [SI, HSI]>, DwarfRegNum<[-2, 6, 6]>;
148 def EDI : X86Reg<"edi", 7, [DI, HDI]>, DwarfRegNum<[-2, 7, 7]>;
149 def EBP : X86Reg<"ebp", 5, [BP, HBP]>, DwarfRegNum<[-2, 4, 5]>;
150 def ESP : X86Reg<"esp", 4, [SP, HSP]>, DwarfRegNum<[-2, 5, 4]>;
151 def EIP : X86Reg<"eip", 0, [IP, HIP]>, DwarfRegNum<[-2, 8, 8]>;
154 // X86-64 only, requires REX
155 let SubRegIndices = [sub_16bit, sub_16bit_hi], CostPerUse = 1,
156 CoveredBySubRegs = 1 in {
157 def R8D : X86Reg<"r8d", 8, [R8W,R8WH]>;
158 def R9D : X86Reg<"r9d", 9, [R9W,R9WH]>;
159 def R10D : X86Reg<"r10d", 10, [R10W,R10WH]>;
160 def R11D : X86Reg<"r11d", 11, [R11W,R11WH]>;
161 def R12D : X86Reg<"r12d", 12, [R12W,R12WH]>;
162 def R13D : X86Reg<"r13d", 13, [R13W,R13WH]>;
163 def R14D : X86Reg<"r14d", 14, [R14W,R14WH]>;
164 def R15D : X86Reg<"r15d", 15, [R15W,R15WH]>;
167 // 64-bit registers, X86-64 only
168 let SubRegIndices = [sub_32bit] in {
169 def RAX : X86Reg<"rax", 0, [EAX]>, DwarfRegNum<[0, -2, -2]>;
170 def RDX : X86Reg<"rdx", 2, [EDX]>, DwarfRegNum<[1, -2, -2]>;
171 def RCX : X86Reg<"rcx", 1, [ECX]>, DwarfRegNum<[2, -2, -2]>;
172 def RBX : X86Reg<"rbx", 3, [EBX]>, DwarfRegNum<[3, -2, -2]>;
173 def RSI : X86Reg<"rsi", 6, [ESI]>, DwarfRegNum<[4, -2, -2]>;
174 def RDI : X86Reg<"rdi", 7, [EDI]>, DwarfRegNum<[5, -2, -2]>;
175 def RBP : X86Reg<"rbp", 5, [EBP]>, DwarfRegNum<[6, -2, -2]>;
176 def RSP : X86Reg<"rsp", 4, [ESP]>, DwarfRegNum<[7, -2, -2]>;
178 // These also require REX.
179 let CostPerUse = 1 in {
180 def R8 : X86Reg<"r8", 8, [R8D]>, DwarfRegNum<[ 8, -2, -2]>;
181 def R9 : X86Reg<"r9", 9, [R9D]>, DwarfRegNum<[ 9, -2, -2]>;
182 def R10 : X86Reg<"r10", 10, [R10D]>, DwarfRegNum<[10, -2, -2]>;
183 def R11 : X86Reg<"r11", 11, [R11D]>, DwarfRegNum<[11, -2, -2]>;
184 def R12 : X86Reg<"r12", 12, [R12D]>, DwarfRegNum<[12, -2, -2]>;
185 def R13 : X86Reg<"r13", 13, [R13D]>, DwarfRegNum<[13, -2, -2]>;
186 def R14 : X86Reg<"r14", 14, [R14D]>, DwarfRegNum<[14, -2, -2]>;
187 def R15 : X86Reg<"r15", 15, [R15D]>, DwarfRegNum<[15, -2, -2]>;
188 def RIP : X86Reg<"rip", 0, [EIP]>, DwarfRegNum<[16, -2, -2]>;
191 // MMX Registers. These are actually aliased to ST0 .. ST7
192 def MM0 : X86Reg<"mm0", 0>, DwarfRegNum<[41, 29, 29]>;
193 def MM1 : X86Reg<"mm1", 1>, DwarfRegNum<[42, 30, 30]>;
194 def MM2 : X86Reg<"mm2", 2>, DwarfRegNum<[43, 31, 31]>;
195 def MM3 : X86Reg<"mm3", 3>, DwarfRegNum<[44, 32, 32]>;
196 def MM4 : X86Reg<"mm4", 4>, DwarfRegNum<[45, 33, 33]>;
197 def MM5 : X86Reg<"mm5", 5>, DwarfRegNum<[46, 34, 34]>;
198 def MM6 : X86Reg<"mm6", 6>, DwarfRegNum<[47, 35, 35]>;
199 def MM7 : X86Reg<"mm7", 7>, DwarfRegNum<[48, 36, 36]>;
201 // Pseudo Floating Point registers
202 def FP0 : X86Reg<"fp0", 0>;
203 def FP1 : X86Reg<"fp1", 0>;
204 def FP2 : X86Reg<"fp2", 0>;
205 def FP3 : X86Reg<"fp3", 0>;
206 def FP4 : X86Reg<"fp4", 0>;
207 def FP5 : X86Reg<"fp5", 0>;
208 def FP6 : X86Reg<"fp6", 0>;
209 def FP7 : X86Reg<"fp7", 0>;
211 // XMM Registers, used by the various SSE instruction set extensions.
212 def XMM0: X86Reg<"xmm0", 0>, DwarfRegNum<[17, 21, 21]>;
213 def XMM1: X86Reg<"xmm1", 1>, DwarfRegNum<[18, 22, 22]>;
214 def XMM2: X86Reg<"xmm2", 2>, DwarfRegNum<[19, 23, 23]>;
215 def XMM3: X86Reg<"xmm3", 3>, DwarfRegNum<[20, 24, 24]>;
216 def XMM4: X86Reg<"xmm4", 4>, DwarfRegNum<[21, 25, 25]>;
217 def XMM5: X86Reg<"xmm5", 5>, DwarfRegNum<[22, 26, 26]>;
218 def XMM6: X86Reg<"xmm6", 6>, DwarfRegNum<[23, 27, 27]>;
219 def XMM7: X86Reg<"xmm7", 7>, DwarfRegNum<[24, 28, 28]>;
222 let CostPerUse = 1 in {
223 def XMM8: X86Reg<"xmm8", 8>, DwarfRegNum<[25, -2, -2]>;
224 def XMM9: X86Reg<"xmm9", 9>, DwarfRegNum<[26, -2, -2]>;
225 def XMM10: X86Reg<"xmm10", 10>, DwarfRegNum<[27, -2, -2]>;
226 def XMM11: X86Reg<"xmm11", 11>, DwarfRegNum<[28, -2, -2]>;
227 def XMM12: X86Reg<"xmm12", 12>, DwarfRegNum<[29, -2, -2]>;
228 def XMM13: X86Reg<"xmm13", 13>, DwarfRegNum<[30, -2, -2]>;
229 def XMM14: X86Reg<"xmm14", 14>, DwarfRegNum<[31, -2, -2]>;
230 def XMM15: X86Reg<"xmm15", 15>, DwarfRegNum<[32, -2, -2]>;
232 def XMM16: X86Reg<"xmm16", 16>, DwarfRegNum<[67, -2, -2]>;
233 def XMM17: X86Reg<"xmm17", 17>, DwarfRegNum<[68, -2, -2]>;
234 def XMM18: X86Reg<"xmm18", 18>, DwarfRegNum<[69, -2, -2]>;
235 def XMM19: X86Reg<"xmm19", 19>, DwarfRegNum<[70, -2, -2]>;
236 def XMM20: X86Reg<"xmm20", 20>, DwarfRegNum<[71, -2, -2]>;
237 def XMM21: X86Reg<"xmm21", 21>, DwarfRegNum<[72, -2, -2]>;
238 def XMM22: X86Reg<"xmm22", 22>, DwarfRegNum<[73, -2, -2]>;
239 def XMM23: X86Reg<"xmm23", 23>, DwarfRegNum<[74, -2, -2]>;
240 def XMM24: X86Reg<"xmm24", 24>, DwarfRegNum<[75, -2, -2]>;
241 def XMM25: X86Reg<"xmm25", 25>, DwarfRegNum<[76, -2, -2]>;
242 def XMM26: X86Reg<"xmm26", 26>, DwarfRegNum<[77, -2, -2]>;
243 def XMM27: X86Reg<"xmm27", 27>, DwarfRegNum<[78, -2, -2]>;
244 def XMM28: X86Reg<"xmm28", 28>, DwarfRegNum<[79, -2, -2]>;
245 def XMM29: X86Reg<"xmm29", 29>, DwarfRegNum<[80, -2, -2]>;
246 def XMM30: X86Reg<"xmm30", 30>, DwarfRegNum<[81, -2, -2]>;
247 def XMM31: X86Reg<"xmm31", 31>, DwarfRegNum<[82, -2, -2]>;
251 // YMM0-15 registers, used by AVX instructions and
252 // YMM16-31 registers, used by AVX-512 instructions.
253 let SubRegIndices = [sub_xmm] in {
254 foreach Index = 0-31 in {
255 def YMM#Index : X86Reg<"ymm"#Index, Index, [!cast<X86Reg>("XMM"#Index)]>,
256 DwarfRegAlias<!cast<X86Reg>("XMM"#Index)>;
260 // ZMM Registers, used by AVX-512 instructions.
261 let SubRegIndices = [sub_ymm] in {
262 foreach Index = 0-31 in {
263 def ZMM#Index : X86Reg<"zmm"#Index, Index, [!cast<X86Reg>("YMM"#Index)]>,
264 DwarfRegAlias<!cast<X86Reg>("XMM"#Index)>;
268 // Mask Registers, used by AVX-512 instructions.
269 def K0 : X86Reg<"k0", 0>, DwarfRegNum<[118, 93, 93]>;
270 def K1 : X86Reg<"k1", 1>, DwarfRegNum<[119, 94, 94]>;
271 def K2 : X86Reg<"k2", 2>, DwarfRegNum<[120, 95, 95]>;
272 def K3 : X86Reg<"k3", 3>, DwarfRegNum<[121, 96, 96]>;
273 def K4 : X86Reg<"k4", 4>, DwarfRegNum<[122, 97, 97]>;
274 def K5 : X86Reg<"k5", 5>, DwarfRegNum<[123, 98, 98]>;
275 def K6 : X86Reg<"k6", 6>, DwarfRegNum<[124, 99, 99]>;
276 def K7 : X86Reg<"k7", 7>, DwarfRegNum<[125, 100, 100]>;
278 // Floating point stack registers. These don't map one-to-one to the FP
279 // pseudo registers, but we still mark them as aliasing FP registers. That
280 // way both kinds can be live without exceeding the stack depth. ST registers
281 // are only live around inline assembly.
282 def ST0 : X86Reg<"st", 0>, DwarfRegNum<[33, 12, 11]>;
283 def ST1 : X86Reg<"st(1)", 1>, DwarfRegNum<[34, 13, 12]>;
284 def ST2 : X86Reg<"st(2)", 2>, DwarfRegNum<[35, 14, 13]>;
285 def ST3 : X86Reg<"st(3)", 3>, DwarfRegNum<[36, 15, 14]>;
286 def ST4 : X86Reg<"st(4)", 4>, DwarfRegNum<[37, 16, 15]>;
287 def ST5 : X86Reg<"st(5)", 5>, DwarfRegNum<[38, 17, 16]>;
288 def ST6 : X86Reg<"st(6)", 6>, DwarfRegNum<[39, 18, 17]>;
289 def ST7 : X86Reg<"st(7)", 7>, DwarfRegNum<[40, 19, 18]>;
291 // Floating-point status word
292 def FPSW : X86Reg<"fpsr", 0>;
294 // Floating-point control word
295 def FPCW : X86Reg<"fpcr", 0>;
297 // SIMD Floating-point control register.
298 // Note: We only model the "Uses" of the control bits: current rounding modes,
299 // DAZ, FTZ and exception masks. We don't model the "Defs" of flag bits.
300 def MXCSR : X86Reg<"mxcsr", 0>;
302 // Status flags register.
304 // Note that some flags that are commonly thought of as part of the status
305 // flags register are modeled separately. Typically this is due to instructions
306 // reading and updating those flags independently of all the others. We don't
307 // want to create false dependencies between these instructions and so we use
308 // a separate register to model them.
309 def EFLAGS : X86Reg<"flags", 0>;
311 // The direction flag.
312 def DF : X86Reg<"dirflag", 0>;
316 def CS : X86Reg<"cs", 1>;
317 def DS : X86Reg<"ds", 3>;
318 def SS : X86Reg<"ss", 2>;
319 def ES : X86Reg<"es", 0>;
320 def FS : X86Reg<"fs", 4>;
321 def GS : X86Reg<"gs", 5>;
324 def DR0 : X86Reg<"dr0", 0>;
325 def DR1 : X86Reg<"dr1", 1>;
326 def DR2 : X86Reg<"dr2", 2>;
327 def DR3 : X86Reg<"dr3", 3>;
328 def DR4 : X86Reg<"dr4", 4>;
329 def DR5 : X86Reg<"dr5", 5>;
330 def DR6 : X86Reg<"dr6", 6>;
331 def DR7 : X86Reg<"dr7", 7>;
332 def DR8 : X86Reg<"dr8", 8>;
333 def DR9 : X86Reg<"dr9", 9>;
334 def DR10 : X86Reg<"dr10", 10>;
335 def DR11 : X86Reg<"dr11", 11>;
336 def DR12 : X86Reg<"dr12", 12>;
337 def DR13 : X86Reg<"dr13", 13>;
338 def DR14 : X86Reg<"dr14", 14>;
339 def DR15 : X86Reg<"dr15", 15>;
342 def CR0 : X86Reg<"cr0", 0>;
343 def CR1 : X86Reg<"cr1", 1>;
344 def CR2 : X86Reg<"cr2", 2>;
345 def CR3 : X86Reg<"cr3", 3>;
346 def CR4 : X86Reg<"cr4", 4>;
347 def CR5 : X86Reg<"cr5", 5>;
348 def CR6 : X86Reg<"cr6", 6>;
349 def CR7 : X86Reg<"cr7", 7>;
350 def CR8 : X86Reg<"cr8", 8>;
351 def CR9 : X86Reg<"cr9", 9>;
352 def CR10 : X86Reg<"cr10", 10>;
353 def CR11 : X86Reg<"cr11", 11>;
354 def CR12 : X86Reg<"cr12", 12>;
355 def CR13 : X86Reg<"cr13", 13>;
356 def CR14 : X86Reg<"cr14", 14>;
357 def CR15 : X86Reg<"cr15", 15>;
359 // Pseudo index registers
360 def EIZ : X86Reg<"eiz", 4>;
361 def RIZ : X86Reg<"riz", 4>;
363 // Bound registers, used in MPX instructions
364 def BND0 : X86Reg<"bnd0", 0>;
365 def BND1 : X86Reg<"bnd1", 1>;
366 def BND2 : X86Reg<"bnd2", 2>;
367 def BND3 : X86Reg<"bnd3", 3>;
369 // CET registers - Shadow Stack Pointer
370 def SSP : X86Reg<"ssp", 0>;
372 //===----------------------------------------------------------------------===//
373 // Register Class Definitions... now that we have all of the pieces, define the
374 // top-level register classes. The order specified in the register list is
375 // implicitly defined to be the register allocation order.
378 // List call-clobbered registers before callee-save registers. RBX, RBP, (and
379 // R12, R13, R14, and R15 for X86-64) are callee-save registers.
380 // In 64-mode, there are 12 additional i8 registers, SIL, DIL, BPL, SPL, and
382 // Allocate R12 and R13 last, as these require an extra byte when
383 // encoded in x86_64 instructions.
384 // FIXME: Allow AH, CH, DH, BH to be used as general-purpose registers in
385 // 64-bit mode. The main complication is that they cannot be encoded in an
386 // instruction requiring a REX prefix, while SIL, DIL, BPL, R8D, etc.
387 // require a REX prefix. For example, "addb %ah, %dil" and "movzbl %ah, %r8d"
388 // cannot be encoded.
389 def GR8 : RegisterClass<"X86", [i8], 8,
390 (add AL, CL, DL, AH, CH, DH, BL, BH, SIL, DIL, BPL, SPL,
391 R8B, R9B, R10B, R11B, R14B, R15B, R12B, R13B)> {
392 let AltOrders = [(sub GR8, AH, BH, CH, DH)];
393 let AltOrderSelect = [{
394 return MF.getSubtarget<X86Subtarget>().is64Bit();
398 let isAllocatable = 0 in
399 def GRH8 : RegisterClass<"X86", [i8], 8,
400 (add SIH, DIH, BPH, SPH, R8BH, R9BH, R10BH, R11BH,
401 R12BH, R13BH, R14BH, R15BH)>;
403 def GR16 : RegisterClass<"X86", [i16], 16,
404 (add AX, CX, DX, SI, DI, BX, BP, SP,
405 R8W, R9W, R10W, R11W, R14W, R15W, R12W, R13W)>;
407 let isAllocatable = 0 in
408 def GRH16 : RegisterClass<"X86", [i16], 16,
409 (add HAX, HCX, HDX, HSI, HDI, HBX, HBP, HSP, HIP,
410 R8WH, R9WH, R10WH, R11WH, R12WH, R13WH, R14WH,
413 def GR32 : RegisterClass<"X86", [i32], 32,
414 (add EAX, ECX, EDX, ESI, EDI, EBX, EBP, ESP,
415 R8D, R9D, R10D, R11D, R14D, R15D, R12D, R13D)>;
417 // GR64 - 64-bit GPRs. This oddly includes RIP, which isn't accurate, since
418 // RIP isn't really a register and it can't be used anywhere except in an
419 // address, but it doesn't cause trouble.
420 // FIXME: it *does* cause trouble - CheckBaseRegAndIndexReg() has extra
421 // tests because of the inclusion of RIP in this register class.
422 def GR64 : RegisterClass<"X86", [i64], 64,
423 (add RAX, RCX, RDX, RSI, RDI, R8, R9, R10, R11,
424 RBX, R14, R15, R12, R13, RBP, RSP, RIP)>;
426 // Segment registers for use by MOV instructions (and others) that have a
427 // segment register as one operand. Always contain a 16-bit segment
429 def SEGMENT_REG : RegisterClass<"X86", [i16], 16, (add CS, DS, SS, ES, FS, GS)>;
432 def DEBUG_REG : RegisterClass<"X86", [i32], 32, (sequence "DR%u", 0, 15)>;
434 // Control registers.
435 def CONTROL_REG : RegisterClass<"X86", [i64], 64, (sequence "CR%u", 0, 15)>;
437 // GR8_ABCD_L, GR8_ABCD_H, GR16_ABCD, GR32_ABCD, GR64_ABCD - Subclasses of
438 // GR8, GR16, GR32, and GR64 which contain just the "a" "b", "c", and "d"
439 // registers. On x86-32, GR16_ABCD and GR32_ABCD are classes for registers
440 // that support 8-bit subreg operations. On x86-64, GR16_ABCD, GR32_ABCD,
441 // and GR64_ABCD are classes for registers that support 8-bit h-register
443 def GR8_ABCD_L : RegisterClass<"X86", [i8], 8, (add AL, CL, DL, BL)>;
444 def GR8_ABCD_H : RegisterClass<"X86", [i8], 8, (add AH, CH, DH, BH)>;
445 def GR16_ABCD : RegisterClass<"X86", [i16], 16, (add AX, CX, DX, BX)>;
446 def GR32_ABCD : RegisterClass<"X86", [i32], 32, (add EAX, ECX, EDX, EBX)>;
447 def GR64_ABCD : RegisterClass<"X86", [i64], 64, (add RAX, RCX, RDX, RBX)>;
448 def GR32_TC : RegisterClass<"X86", [i32], 32, (add EAX, ECX, EDX, ESP)>;
449 def GR64_TC : RegisterClass<"X86", [i64], 64, (add RAX, RCX, RDX, RSI, RDI,
450 R8, R9, R11, RIP, RSP)>;
451 def GR64_TCW64 : RegisterClass<"X86", [i64], 64, (add RAX, RCX, RDX,
455 // GR8_NOREX - GR8 registers which do not require a REX prefix.
456 def GR8_NOREX : RegisterClass<"X86", [i8], 8,
457 (add AL, CL, DL, AH, CH, DH, BL, BH)> {
458 let AltOrders = [(sub GR8_NOREX, AH, BH, CH, DH)];
459 let AltOrderSelect = [{
460 return MF.getSubtarget<X86Subtarget>().is64Bit();
463 // GR16_NOREX - GR16 registers which do not require a REX prefix.
464 def GR16_NOREX : RegisterClass<"X86", [i16], 16,
465 (add AX, CX, DX, SI, DI, BX, BP, SP)>;
466 // GR32_NOREX - GR32 registers which do not require a REX prefix.
467 def GR32_NOREX : RegisterClass<"X86", [i32], 32,
468 (add EAX, ECX, EDX, ESI, EDI, EBX, EBP, ESP)>;
469 // GR64_NOREX - GR64 registers which do not require a REX prefix.
470 def GR64_NOREX : RegisterClass<"X86", [i64], 64,
471 (add RAX, RCX, RDX, RSI, RDI, RBX, RBP, RSP, RIP)>;
473 // GR32_NOSP - GR32 registers except ESP.
474 def GR32_NOSP : RegisterClass<"X86", [i32], 32, (sub GR32, ESP)>;
476 // GR64_NOSP - GR64 registers except RSP (and RIP).
477 def GR64_NOSP : RegisterClass<"X86", [i64], 64, (sub GR64, RSP, RIP)>;
479 // GR32_NOREX_NOSP - GR32 registers which do not require a REX prefix except
481 def GR32_NOREX_NOSP : RegisterClass<"X86", [i32], 32,
482 (and GR32_NOREX, GR32_NOSP)>;
484 // GR64_NOREX_NOSP - GR64_NOREX registers except RSP.
485 def GR64_NOREX_NOSP : RegisterClass<"X86", [i64], 64,
486 (and GR64_NOREX, GR64_NOSP)>;
488 // Register classes used for ABIs that use 32-bit address accesses,
489 // while using the whole x84_64 ISA.
491 // In such cases, it is fine to use RIP as we are sure the 32 high
492 // bits are not set. We do not need variants for NOSP as RIP is not
494 // RIP is not spilled anywhere for now, so stick to 32-bit alignment
495 // to save on memory space.
496 // FIXME: We could allow all 64bit registers, but we would need
497 // something to check that the 32 high bits are not set,
498 // which we do not have right now.
499 def LOW32_ADDR_ACCESS : RegisterClass<"X86", [i32], 32, (add GR32, RIP)>;
501 // When RBP is used as a base pointer in a 32-bit addresses environement,
502 // this is also safe to use the full register to access addresses.
503 // Since RBP will never be spilled, stick to a 32 alignment to save
504 // on memory consumption.
505 def LOW32_ADDR_ACCESS_RBP : RegisterClass<"X86", [i32], 32,
506 (add LOW32_ADDR_ACCESS, RBP)>;
508 // A class to support the 'A' assembler constraint: [ER]AX then [ER]DX.
509 def GR32_AD : RegisterClass<"X86", [i32], 32, (add EAX, EDX)>;
510 def GR64_AD : RegisterClass<"X86", [i64], 64, (add RAX, RDX)>;
512 // Classes to support the 64-bit assembler constraint tied to a fixed
513 // register in 32-bit mode. The second register is always the next in
514 // the list. Wrap around causes an error.
515 def GR32_DC : RegisterClass<"X86", [i32], 32, (add EDX, ECX)>;
516 def GR32_CB : RegisterClass<"X86", [i32], 32, (add ECX, EBX)>;
517 def GR32_BSI : RegisterClass<"X86", [i32], 32, (add EBX, ESI)>;
518 def GR32_SIDI : RegisterClass<"X86", [i32], 32, (add ESI, EDI)>;
519 def GR32_DIBP : RegisterClass<"X86", [i32], 32, (add EDI, EBP)>;
520 def GR32_BPSP : RegisterClass<"X86", [i32], 32, (add EBP, ESP)>;
522 // Scalar SSE2 floating point registers.
523 def FR32 : RegisterClass<"X86", [f32], 32, (sequence "XMM%u", 0, 15)>;
525 def FR64 : RegisterClass<"X86", [f64], 64, (add FR32)>;
528 // FIXME: This sets up the floating point register files as though they are f64
529 // values, though they really are f80 values. This will cause us to spill
530 // values as 64-bit quantities instead of 80-bit quantities, which is much much
531 // faster on common hardware. In reality, this should be controlled by a
532 // command line option or something.
535 def RFP32 : RegisterClass<"X86",[f32], 32, (sequence "FP%u", 0, 6)>;
536 def RFP64 : RegisterClass<"X86",[f64], 32, (add RFP32)>;
537 def RFP80 : RegisterClass<"X86",[f80], 32, (add RFP32)>;
539 // st(7) may be is not allocatable.
540 def RFP80_7 : RegisterClass<"X86",[f80], 32, (add FP7)> {
541 let isAllocatable = 0;
544 // Floating point stack registers (these are not allocatable by the
545 // register allocator - the floating point stackifier is responsible
546 // for transforming FPn allocations to STn registers)
547 def RST : RegisterClass<"X86", [f80, f64, f32], 32, (sequence "ST%u", 0, 7)> {
548 let isAllocatable = 0;
551 // Helper to allow %st to print as %st(0) when its encoded in the instruction.
552 def RSTi : RegisterOperand<RST, "printSTiRegOperand">;
554 // Generic vector registers: VR64 and VR128.
555 // Ensure that float types are declared first - only float is legal on SSE1.
556 def VR64: RegisterClass<"X86", [x86mmx], 64, (sequence "MM%u", 0, 7)>;
557 def VR128 : RegisterClass<"X86", [v4f32, v2f64, v16i8, v8i16, v4i32, v2i64, f128],
559 def VR256 : RegisterClass<"X86", [v8f32, v4f64, v32i8, v16i16, v8i32, v4i64],
560 256, (sequence "YMM%u", 0, 15)>;
562 // Status flags registers.
563 def CCR : RegisterClass<"X86", [i32], 32, (add EFLAGS)> {
564 let CopyCost = -1; // Don't allow copying of status registers.
565 let isAllocatable = 0;
567 def FPCCR : RegisterClass<"X86", [i16], 16, (add FPSW)> {
568 let CopyCost = -1; // Don't allow copying of status registers.
569 let isAllocatable = 0;
571 def DFCCR : RegisterClass<"X86", [i32], 32, (add DF)> {
572 let CopyCost = -1; // Don't allow copying of status registers.
573 let isAllocatable = 0;
576 // AVX-512 vector/mask registers.
577 def VR512 : RegisterClass<"X86", [v16f32, v8f64, v64i8, v32i16, v16i32, v8i64],
578 512, (sequence "ZMM%u", 0, 31)>;
580 // Represents the lower 16 registers that have VEX/legacy encodable subregs.
581 def VR512_0_15 : RegisterClass<"X86", [v16f32, v8f64, v64i8, v32i16, v16i32, v8i64],
582 512, (sequence "ZMM%u", 0, 15)>;
584 // Scalar AVX-512 floating point registers.
585 def FR32X : RegisterClass<"X86", [f32], 32, (sequence "XMM%u", 0, 31)>;
587 def FR64X : RegisterClass<"X86", [f64], 64, (add FR32X)>;
589 // Extended VR128 and VR256 for AVX-512 instructions
590 def VR128X : RegisterClass<"X86", [v4f32, v2f64, v16i8, v8i16, v4i32, v2i64, f128],
592 def VR256X : RegisterClass<"X86", [v8f32, v4f64, v32i8, v16i16, v8i32, v4i64],
593 256, (sequence "YMM%u", 0, 31)>;
596 def VK1 : RegisterClass<"X86", [v1i1], 16, (sequence "K%u", 0, 7)> {let Size = 16;}
597 def VK2 : RegisterClass<"X86", [v2i1], 16, (add VK1)> {let Size = 16;}
598 def VK4 : RegisterClass<"X86", [v4i1], 16, (add VK2)> {let Size = 16;}
599 def VK8 : RegisterClass<"X86", [v8i1], 16, (add VK4)> {let Size = 16;}
600 def VK16 : RegisterClass<"X86", [v16i1], 16, (add VK8)> {let Size = 16;}
601 def VK32 : RegisterClass<"X86", [v32i1], 32, (add VK16)> {let Size = 32;}
602 def VK64 : RegisterClass<"X86", [v64i1], 64, (add VK32)> {let Size = 64;}
604 // Mask register pairs
605 def KPAIRS : RegisterTuples<[sub_mask_0, sub_mask_1],
606 [(add K0, K2, K4, K6), (add K1, K3, K5, K7)]>;
608 def VK1PAIR : RegisterClass<"X86", [untyped], 16, (add KPAIRS)> {let Size = 32;}
609 def VK2PAIR : RegisterClass<"X86", [untyped], 16, (add KPAIRS)> {let Size = 32;}
610 def VK4PAIR : RegisterClass<"X86", [untyped], 16, (add KPAIRS)> {let Size = 32;}
611 def VK8PAIR : RegisterClass<"X86", [untyped], 16, (add KPAIRS)> {let Size = 32;}
612 def VK16PAIR : RegisterClass<"X86", [untyped], 16, (add KPAIRS)> {let Size = 32;}
614 def VK1WM : RegisterClass<"X86", [v1i1], 16, (sub VK1, K0)> {let Size = 16;}
615 def VK2WM : RegisterClass<"X86", [v2i1], 16, (sub VK2, K0)> {let Size = 16;}
616 def VK4WM : RegisterClass<"X86", [v4i1], 16, (sub VK4, K0)> {let Size = 16;}
617 def VK8WM : RegisterClass<"X86", [v8i1], 16, (sub VK8, K0)> {let Size = 16;}
618 def VK16WM : RegisterClass<"X86", [v16i1], 16, (add VK8WM)> {let Size = 16;}
619 def VK32WM : RegisterClass<"X86", [v32i1], 32, (add VK16WM)> {let Size = 32;}
620 def VK64WM : RegisterClass<"X86", [v64i1], 64, (add VK32WM)> {let Size = 64;}
623 def BNDR : RegisterClass<"X86", [v2i64], 128, (sequence "BND%u", 0, 3)>;