xref: /freebsd/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVInstrFormats.td (revision 5e801ac66d24704442eba426ed13c3effb8a34e7)
1//===-- RISCVInstrFormats.td - RISCV Instruction Formats ---*- tablegen -*-===//
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//===----------------------------------------------------------------------===//
10//
11//  These instruction format definitions are structured to match the
12//  description in the RISC-V User-Level ISA specification as closely as
13//  possible. For instance, the specification describes instructions with the
14//  MSB (31st bit) on the left and the LSB (0th bit) on the right. This is
15//  reflected in the order of parameters to each instruction class.
16//
17//  One area of divergence is in the description of immediates. The
18//  specification describes immediate encoding in terms of bit-slicing
19//  operations on the logical value represented. The immediate argument to
20//  these instruction formats instead represents the bit sequence that will be
21//  inserted into the instruction. e.g. although JAL's immediate is logically
22//  a 21-bit value (where the LSB is always zero), we describe it as an imm20
23//  to match how it is encoded.
24//
25//===----------------------------------------------------------------------===//
26
27// Format specifies the encoding used by the instruction. This is used by
28// RISCVMCCodeEmitter to determine which form of fixup to use. These
29// definitions must be kept in-sync with RISCVBaseInfo.h.
30class InstFormat<bits<5> val> {
31  bits<5> Value = val;
32}
33def InstFormatPseudo : InstFormat<0>;
34def InstFormatR      : InstFormat<1>;
35def InstFormatR4     : InstFormat<2>;
36def InstFormatI      : InstFormat<3>;
37def InstFormatS      : InstFormat<4>;
38def InstFormatB      : InstFormat<5>;
39def InstFormatU      : InstFormat<6>;
40def InstFormatJ      : InstFormat<7>;
41def InstFormatCR     : InstFormat<8>;
42def InstFormatCI     : InstFormat<9>;
43def InstFormatCSS    : InstFormat<10>;
44def InstFormatCIW    : InstFormat<11>;
45def InstFormatCL     : InstFormat<12>;
46def InstFormatCS     : InstFormat<13>;
47def InstFormatCA     : InstFormat<14>;
48def InstFormatCB     : InstFormat<15>;
49def InstFormatCJ     : InstFormat<16>;
50def InstFormatOther  : InstFormat<17>;
51
52class RISCVVConstraint<bits<3> val> {
53  bits<3> Value = val;
54}
55def NoConstraint  : RISCVVConstraint<0b000>;
56def VS2Constraint : RISCVVConstraint<0b001>;
57def VS1Constraint : RISCVVConstraint<0b010>;
58def VMConstraint  : RISCVVConstraint<0b100>;
59
60// Illegal instructions:
61//
62// * The destination vector register group for a masked vector instruction
63// cannot overlap the source mask register (v0), unless the destination vector
64// register is being written with a mask value (e.g., comparisons) or the
65// scalar result of a reduction.
66//
67// * Widening: The destination EEW is greater than the source EEW, the source
68// EMUL is at least 1. The destination vector register group cannot overlap
69// with the source vector register groups besides the highest-numbered part of
70// the destination register group.
71//
72// * Narrowing: The destination EEW is smaller than the source EEW. The
73// destination vector register group cannot overlap with the source vector
74// register groups besides the lowest-numbered part of the source register
75// group.
76//
77// * vmsbf.m/vmsif.m/vmsof.m: The destination register cannot overlap the
78// source register and, if masked, cannot overlap the mask register ('v0').
79//
80// * viota: The destination register cannot overlap the source register and,
81// if masked, cannot overlap the mask register ('v0').
82//
83// * v[f]slide[1]up: The destination vector register group for vslideup cannot
84// overlap the source vector register group.
85//
86// * vrgather: The destination vector register group cannot overlap with the
87// source vector register groups.
88//
89// * vcompress: The destination vector register group cannot overlap the
90// source vector register group or the source mask register
91def WidenV       : RISCVVConstraint<!or(VS2Constraint.Value,
92                                        VS1Constraint.Value,
93                                        VMConstraint.Value)>;
94def WidenW       : RISCVVConstraint<!or(VS1Constraint.Value,
95                                        VMConstraint.Value)>;
96def WidenCvt     : RISCVVConstraint<!or(VS2Constraint.Value,
97                                        VMConstraint.Value)>;
98def Iota         : RISCVVConstraint<!or(VS2Constraint.Value,
99                                        VMConstraint.Value)>;
100def SlideUp      : RISCVVConstraint<!or(VS2Constraint.Value,
101                                        VMConstraint.Value)>;
102def Vrgather     : RISCVVConstraint<!or(VS2Constraint.Value,
103                                        VS1Constraint.Value,
104                                        VMConstraint.Value)>;
105def Vcompress    : RISCVVConstraint<!or(VS2Constraint.Value,
106                                        VS1Constraint.Value)>;
107
108// The following opcode names match those given in Table 19.1 in the
109// RISC-V User-level ISA specification ("RISC-V base opcode map").
110class RISCVOpcode<bits<7> val> {
111  bits<7> Value = val;
112}
113def OPC_LOAD      : RISCVOpcode<0b0000011>;
114def OPC_LOAD_FP   : RISCVOpcode<0b0000111>;
115def OPC_MISC_MEM  : RISCVOpcode<0b0001111>;
116def OPC_OP_IMM    : RISCVOpcode<0b0010011>;
117def OPC_AUIPC     : RISCVOpcode<0b0010111>;
118def OPC_OP_IMM_32 : RISCVOpcode<0b0011011>;
119def OPC_STORE     : RISCVOpcode<0b0100011>;
120def OPC_STORE_FP  : RISCVOpcode<0b0100111>;
121def OPC_AMO       : RISCVOpcode<0b0101111>;
122def OPC_OP        : RISCVOpcode<0b0110011>;
123def OPC_LUI       : RISCVOpcode<0b0110111>;
124def OPC_OP_32     : RISCVOpcode<0b0111011>;
125def OPC_MADD      : RISCVOpcode<0b1000011>;
126def OPC_MSUB      : RISCVOpcode<0b1000111>;
127def OPC_NMSUB     : RISCVOpcode<0b1001011>;
128def OPC_NMADD     : RISCVOpcode<0b1001111>;
129def OPC_OP_FP     : RISCVOpcode<0b1010011>;
130def OPC_OP_V      : RISCVOpcode<0b1010111>;
131def OPC_BRANCH    : RISCVOpcode<0b1100011>;
132def OPC_JALR      : RISCVOpcode<0b1100111>;
133def OPC_JAL       : RISCVOpcode<0b1101111>;
134def OPC_SYSTEM    : RISCVOpcode<0b1110011>;
135
136class RVInst<dag outs, dag ins, string opcodestr, string argstr,
137             list<dag> pattern, InstFormat format>
138    : Instruction {
139  field bits<32> Inst;
140  // SoftFail is a field the disassembler can use to provide a way for
141  // instructions to not match without killing the whole decode process. It is
142  // mainly used for ARM, but Tablegen expects this field to exist or it fails
143  // to build the decode table.
144  field bits<32> SoftFail = 0;
145  let Size = 4;
146
147  bits<7> Opcode = 0;
148
149  let Inst{6-0} = Opcode;
150
151  let Namespace = "RISCV";
152
153  dag OutOperandList = outs;
154  dag InOperandList = ins;
155  let AsmString = opcodestr # "\t" # argstr;
156  let Pattern = pattern;
157
158  let TSFlags{4-0} = format.Value;
159
160  // Defaults
161  RISCVVConstraint RVVConstraint = NoConstraint;
162  let TSFlags{7-5} = RVVConstraint.Value;
163
164  bits<3> VLMul = 0;
165  let TSFlags{10-8} = VLMul;
166
167  bit HasDummyMask = 0;
168  let TSFlags{11} = HasDummyMask;
169
170  bit ForceTailAgnostic = false;
171  let TSFlags{12} = ForceTailAgnostic;
172
173  bit HasMergeOp = 0;
174  let TSFlags{13} = HasMergeOp;
175
176  bit HasSEWOp = 0;
177  let TSFlags{14} = HasSEWOp;
178
179  bit HasVLOp = 0;
180  let TSFlags{15} = HasVLOp;
181
182  bit HasVecPolicyOp = 0;
183  let TSFlags{16} = HasVecPolicyOp;
184
185  bit IsRVVWideningReduction = 0;
186  let TSFlags{17} =  IsRVVWideningReduction;
187}
188
189// Pseudo instructions
190class Pseudo<dag outs, dag ins, list<dag> pattern, string opcodestr = "", string argstr = "">
191    : RVInst<outs, ins, opcodestr, argstr, pattern, InstFormatPseudo>,
192      Sched<[]> {
193  let isPseudo = 1;
194  let isCodeGenOnly = 1;
195}
196
197// Pseudo load instructions.
198class PseudoLoad<string opcodestr, RegisterClass rdty = GPR>
199    : Pseudo<(outs rdty:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr"> {
200  let hasSideEffects = 0;
201  let mayLoad = 1;
202  let mayStore = 0;
203  let isCodeGenOnly = 0;
204  let isAsmParserOnly = 1;
205}
206
207class PseudoFloatLoad<string opcodestr, RegisterClass rdty = GPR>
208    : Pseudo<(outs GPR:$tmp, rdty:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr, $tmp"> {
209  let hasSideEffects = 0;
210  let mayLoad = 1;
211  let mayStore = 0;
212  let isCodeGenOnly = 0;
213  let isAsmParserOnly = 1;
214}
215
216// Pseudo store instructions.
217class PseudoStore<string opcodestr, RegisterClass rsty = GPR>
218    : Pseudo<(outs GPR:$tmp), (ins rsty:$rs, bare_symbol:$addr), [], opcodestr, "$rs, $addr, $tmp"> {
219  let hasSideEffects = 0;
220  let mayLoad = 0;
221  let mayStore = 1;
222  let isCodeGenOnly = 0;
223  let isAsmParserOnly = 1;
224}
225
226// Instruction formats are listed in the order they appear in the RISC-V
227// instruction set manual (R, I, S, B, U, J) with sub-formats (e.g. RVInstR4,
228// RVInstRAtomic) sorted alphabetically.
229
230class RVInstR<bits<7> funct7, bits<3> funct3, RISCVOpcode opcode, dag outs,
231              dag ins, string opcodestr, string argstr>
232    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR> {
233  bits<5> rs2;
234  bits<5> rs1;
235  bits<5> rd;
236
237  let Inst{31-25} = funct7;
238  let Inst{24-20} = rs2;
239  let Inst{19-15} = rs1;
240  let Inst{14-12} = funct3;
241  let Inst{11-7} = rd;
242  let Opcode = opcode.Value;
243}
244
245class RVInstR4<bits<2> funct2, bits<3> funct3, RISCVOpcode opcode, dag outs,
246               dag ins, string opcodestr, string argstr>
247    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR4> {
248  bits<5> rs3;
249  bits<5> rs2;
250  bits<5> rs1;
251  bits<5> rd;
252
253  let Inst{31-27} = rs3;
254  let Inst{26-25} = funct2;
255  let Inst{24-20} = rs2;
256  let Inst{19-15} = rs1;
257  let Inst{14-12} = funct3;
258  let Inst{11-7} = rd;
259  let Opcode = opcode.Value;
260}
261
262class RVInstR4Frm<bits<2> funct2, RISCVOpcode opcode, dag outs, dag ins,
263                  string opcodestr, string argstr>
264    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR4> {
265  bits<5> rs3;
266  bits<5> rs2;
267  bits<5> rs1;
268  bits<3> funct3;
269  bits<5> rd;
270
271  let Inst{31-27} = rs3;
272  let Inst{26-25} = funct2;
273  let Inst{24-20} = rs2;
274  let Inst{19-15} = rs1;
275  let Inst{14-12} = funct3;
276  let Inst{11-7} = rd;
277  let Opcode = opcode.Value;
278}
279
280class RVInstRAtomic<bits<5> funct5, bit aq, bit rl, bits<3> funct3,
281                    RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
282                    string argstr>
283    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR> {
284  bits<5> rs2;
285  bits<5> rs1;
286  bits<5> rd;
287
288  let Inst{31-27} = funct5;
289  let Inst{26} = aq;
290  let Inst{25} = rl;
291  let Inst{24-20} = rs2;
292  let Inst{19-15} = rs1;
293  let Inst{14-12} = funct3;
294  let Inst{11-7} = rd;
295  let Opcode = opcode.Value;
296}
297
298class RVInstRFrm<bits<7> funct7, RISCVOpcode opcode, dag outs, dag ins,
299                 string opcodestr, string argstr>
300    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR> {
301  bits<5> rs2;
302  bits<5> rs1;
303  bits<3> funct3;
304  bits<5> rd;
305
306  let Inst{31-25} = funct7;
307  let Inst{24-20} = rs2;
308  let Inst{19-15} = rs1;
309  let Inst{14-12} = funct3;
310  let Inst{11-7} = rd;
311  let Opcode = opcode.Value;
312}
313
314class RVInstI<bits<3> funct3, RISCVOpcode opcode, dag outs, dag ins,
315              string opcodestr, string argstr>
316    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
317  bits<12> imm12;
318  bits<5> rs1;
319  bits<5> rd;
320
321  let Inst{31-20} = imm12;
322  let Inst{19-15} = rs1;
323  let Inst{14-12} = funct3;
324  let Inst{11-7} = rd;
325  let Opcode = opcode.Value;
326}
327
328class RVInstIShift<bits<5> imm11_7, bits<3> funct3, RISCVOpcode opcode,
329                   dag outs, dag ins, string opcodestr, string argstr>
330    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
331  bits<6> shamt;
332  bits<5> rs1;
333  bits<5> rd;
334
335  let Inst{31-27} = imm11_7;
336  let Inst{26} = 0;
337  let Inst{25-20} = shamt;
338  let Inst{19-15} = rs1;
339  let Inst{14-12} = funct3;
340  let Inst{11-7} = rd;
341  let Opcode = opcode.Value;
342}
343
344class RVInstIShiftW<bits<7> imm11_5, bits<3> funct3, RISCVOpcode opcode,
345                    dag outs, dag ins, string opcodestr, string argstr>
346    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
347  bits<5> shamt;
348  bits<5> rs1;
349  bits<5> rd;
350
351  let Inst{31-25} = imm11_5;
352  let Inst{24-20} = shamt;
353  let Inst{19-15} = rs1;
354  let Inst{14-12} = funct3;
355  let Inst{11-7} = rd;
356  let Opcode = opcode.Value;
357}
358
359class RVInstS<bits<3> funct3, RISCVOpcode opcode, dag outs, dag ins,
360              string opcodestr, string argstr>
361    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatS> {
362  bits<12> imm12;
363  bits<5> rs2;
364  bits<5> rs1;
365
366  let Inst{31-25} = imm12{11-5};
367  let Inst{24-20} = rs2;
368  let Inst{19-15} = rs1;
369  let Inst{14-12} = funct3;
370  let Inst{11-7} = imm12{4-0};
371  let Opcode = opcode.Value;
372}
373
374class RVInstB<bits<3> funct3, RISCVOpcode opcode, dag outs, dag ins,
375              string opcodestr, string argstr>
376    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatB> {
377  bits<12> imm12;
378  bits<5> rs2;
379  bits<5> rs1;
380
381  let Inst{31} = imm12{11};
382  let Inst{30-25} = imm12{9-4};
383  let Inst{24-20} = rs2;
384  let Inst{19-15} = rs1;
385  let Inst{14-12} = funct3;
386  let Inst{11-8} = imm12{3-0};
387  let Inst{7} = imm12{10};
388  let Opcode = opcode.Value;
389}
390
391class RVInstU<RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
392              string argstr>
393    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatU> {
394  bits<20> imm20;
395  bits<5> rd;
396
397  let Inst{31-12} = imm20;
398  let Inst{11-7} = rd;
399  let Opcode = opcode.Value;
400}
401
402class RVInstJ<RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
403              string argstr>
404    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatJ> {
405  bits<20> imm20;
406  bits<5> rd;
407
408  let Inst{31} = imm20{19};
409  let Inst{30-21} = imm20{9-0};
410  let Inst{20} = imm20{10};
411  let Inst{19-12} = imm20{18-11};
412  let Inst{11-7} = rd;
413  let Opcode = opcode.Value;
414}
415
416//===----------------------------------------------------------------------===//
417// Instruction classes for .insn directives
418//===----------------------------------------------------------------------===//
419
420class DirectiveInsnR<dag outs, dag ins, string argstr>
421  : RVInst<outs, ins, "", "", [], InstFormatR> {
422  bits<7> opcode;
423  bits<7> funct7;
424  bits<3> funct3;
425
426  bits<5> rs2;
427  bits<5> rs1;
428  bits<5> rd;
429
430  let Inst{31-25} = funct7;
431  let Inst{24-20} = rs2;
432  let Inst{19-15} = rs1;
433  let Inst{14-12} = funct3;
434  let Inst{11-7} = rd;
435  let Opcode = opcode;
436
437  let AsmString = ".insn r " # argstr;
438}
439
440class DirectiveInsnR4<dag outs, dag ins, string argstr>
441  : RVInst<outs, ins, "", "", [], InstFormatR4> {
442  bits<7> opcode;
443  bits<2> funct2;
444  bits<3> funct3;
445
446  bits<5> rs3;
447  bits<5> rs2;
448  bits<5> rs1;
449  bits<5> rd;
450
451  let Inst{31-27} = rs3;
452  let Inst{26-25} = funct2;
453  let Inst{24-20} = rs2;
454  let Inst{19-15} = rs1;
455  let Inst{14-12} = funct3;
456  let Inst{11-7} = rd;
457  let Opcode = opcode;
458
459  let AsmString = ".insn r4 " # argstr;
460}
461
462class DirectiveInsnI<dag outs, dag ins, string argstr>
463  : RVInst<outs, ins, "", "", [], InstFormatI> {
464  bits<7> opcode;
465  bits<3> funct3;
466
467  bits<12> imm12;
468  bits<5> rs1;
469  bits<5> rd;
470
471  let Inst{31-20} = imm12;
472  let Inst{19-15} = rs1;
473  let Inst{14-12} = funct3;
474  let Inst{11-7} = rd;
475  let Opcode = opcode;
476
477  let AsmString = ".insn i " # argstr;
478}
479
480class DirectiveInsnS<dag outs, dag ins, string argstr>
481  : RVInst<outs, ins, "", "", [], InstFormatS> {
482  bits<7> opcode;
483  bits<3> funct3;
484
485  bits<12> imm12;
486  bits<5> rs2;
487  bits<5> rs1;
488
489  let Inst{31-25} = imm12{11-5};
490  let Inst{24-20} = rs2;
491  let Inst{19-15} = rs1;
492  let Inst{14-12} = funct3;
493  let Inst{11-7} = imm12{4-0};
494  let Opcode = opcode;
495
496  let AsmString = ".insn s " # argstr;
497}
498
499class DirectiveInsnB<dag outs, dag ins, string argstr>
500  : RVInst<outs, ins, "", "", [], InstFormatB> {
501  bits<7> opcode;
502  bits<3> funct3;
503
504  bits<12> imm12;
505  bits<5> rs2;
506  bits<5> rs1;
507
508  let Inst{31} = imm12{11};
509  let Inst{30-25} = imm12{9-4};
510  let Inst{24-20} = rs2;
511  let Inst{19-15} = rs1;
512  let Inst{14-12} = funct3;
513  let Inst{11-8} = imm12{3-0};
514  let Inst{7} = imm12{10};
515  let Opcode = opcode;
516
517  let AsmString = ".insn b " # argstr;
518}
519
520class DirectiveInsnU<dag outs, dag ins, string argstr>
521  : RVInst<outs, ins, "", "", [], InstFormatU> {
522  bits<7> opcode;
523
524  bits<20> imm20;
525  bits<5> rd;
526
527  let Inst{31-12} = imm20;
528  let Inst{11-7} = rd;
529  let Opcode = opcode;
530
531  let AsmString = ".insn u " # argstr;
532}
533
534class DirectiveInsnJ<dag outs, dag ins, string argstr>
535  : RVInst<outs, ins, "", "", [], InstFormatJ> {
536  bits<7> opcode;
537
538  bits<20> imm20;
539  bits<5> rd;
540
541  let Inst{31-12} = imm20;
542  let Inst{11-7} = rd;
543  let Opcode = opcode;
544
545  let AsmString = ".insn j " # argstr;
546}
547