xref: /freebsd/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVInstrFormats.td (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
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<string name, bits<7> val> {
111  string Name = name;
112  bits<7> Value = val;
113}
114def RISCVOpcodesList : GenericTable {
115  let FilterClass = "RISCVOpcode";
116  let Fields = [
117    "Name", "Value"
118  ];
119  let PrimaryKey = [ "Value" ];
120  let PrimaryKeyName = "lookupRISCVOpcodeByValue";
121}
122def lookupRISCVOpcodeByName : SearchIndex {
123  let Table = RISCVOpcodesList;
124  let Key = [ "Name" ];
125}
126def OPC_LOAD      : RISCVOpcode<"LOAD",      0b0000011>;
127def OPC_LOAD_FP   : RISCVOpcode<"LOAD_FP",   0b0000111>;
128def OPC_MISC_MEM  : RISCVOpcode<"MISC_MEM",  0b0001111>;
129def OPC_OP_IMM    : RISCVOpcode<"OP_IMM",    0b0010011>;
130def OPC_AUIPC     : RISCVOpcode<"AUIPC",     0b0010111>;
131def OPC_OP_IMM_32 : RISCVOpcode<"OP_IMM_32", 0b0011011>;
132def OPC_STORE     : RISCVOpcode<"STORE",     0b0100011>;
133def OPC_STORE_FP  : RISCVOpcode<"STORE_FP",  0b0100111>;
134def OPC_AMO       : RISCVOpcode<"AMO",       0b0101111>;
135def OPC_OP        : RISCVOpcode<"OP",        0b0110011>;
136def OPC_LUI       : RISCVOpcode<"LUI",       0b0110111>;
137def OPC_OP_32     : RISCVOpcode<"OP_32",     0b0111011>;
138def OPC_MADD      : RISCVOpcode<"MADD",      0b1000011>;
139def OPC_MSUB      : RISCVOpcode<"MSUB",      0b1000111>;
140def OPC_NMSUB     : RISCVOpcode<"NMSUB",     0b1001011>;
141def OPC_NMADD     : RISCVOpcode<"NMADD",     0b1001111>;
142def OPC_OP_FP     : RISCVOpcode<"OP_FP",     0b1010011>;
143def OPC_OP_V      : RISCVOpcode<"OP_V",      0b1010111>;
144def OPC_BRANCH    : RISCVOpcode<"BRANCH",    0b1100011>;
145def OPC_JALR      : RISCVOpcode<"JALR",      0b1100111>;
146def OPC_JAL       : RISCVOpcode<"JAL",       0b1101111>;
147def OPC_SYSTEM    : RISCVOpcode<"SYSTEM",    0b1110011>;
148
149class RVInst<dag outs, dag ins, string opcodestr, string argstr,
150             list<dag> pattern, InstFormat format>
151    : Instruction {
152  field bits<32> Inst;
153  // SoftFail is a field the disassembler can use to provide a way for
154  // instructions to not match without killing the whole decode process. It is
155  // mainly used for ARM, but Tablegen expects this field to exist or it fails
156  // to build the decode table.
157  field bits<32> SoftFail = 0;
158  let Size = 4;
159
160  bits<7> Opcode = 0;
161
162  let Inst{6-0} = Opcode;
163
164  let Namespace = "RISCV";
165
166  dag OutOperandList = outs;
167  dag InOperandList = ins;
168  let AsmString = opcodestr # "\t" # argstr;
169  let Pattern = pattern;
170
171  let TSFlags{4-0} = format.Value;
172
173  // Defaults
174  RISCVVConstraint RVVConstraint = NoConstraint;
175  let TSFlags{7-5} = RVVConstraint.Value;
176
177  bits<3> VLMul = 0;
178  let TSFlags{10-8} = VLMul;
179
180  bit HasDummyMask = 0;
181  let TSFlags{11} = HasDummyMask;
182
183  bit ForceTailAgnostic = false;
184  let TSFlags{12} = ForceTailAgnostic;
185
186  bit HasMergeOp = 0;
187  let TSFlags{13} = HasMergeOp;
188
189  bit HasSEWOp = 0;
190  let TSFlags{14} = HasSEWOp;
191
192  bit HasVLOp = 0;
193  let TSFlags{15} = HasVLOp;
194
195  bit HasVecPolicyOp = 0;
196  let TSFlags{16} = HasVecPolicyOp;
197
198  bit IsRVVWideningReduction = 0;
199  let TSFlags{17} =  IsRVVWideningReduction;
200}
201
202// Pseudo instructions
203class Pseudo<dag outs, dag ins, list<dag> pattern, string opcodestr = "", string argstr = "">
204    : RVInst<outs, ins, opcodestr, argstr, pattern, InstFormatPseudo> {
205  let isPseudo = 1;
206  let isCodeGenOnly = 1;
207}
208
209class PseudoQuietFCMP<RegisterClass Ty>
210    : Pseudo<(outs GPR:$rd), (ins Ty:$rs1, Ty:$rs2), []> {
211  let hasSideEffects = 1;
212  let mayLoad = 0;
213  let mayStore = 0;
214}
215
216// Pseudo load instructions.
217class PseudoLoad<string opcodestr, RegisterClass rdty = GPR>
218    : Pseudo<(outs rdty:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr"> {
219  let hasSideEffects = 0;
220  let mayLoad = 1;
221  let mayStore = 0;
222  let isCodeGenOnly = 0;
223  let isAsmParserOnly = 1;
224}
225
226class PseudoFloatLoad<string opcodestr, RegisterClass rdty = GPR>
227    : Pseudo<(outs GPR:$tmp, rdty:$rd), (ins bare_symbol:$addr), [], opcodestr, "$rd, $addr, $tmp"> {
228  let hasSideEffects = 0;
229  let mayLoad = 1;
230  let mayStore = 0;
231  let isCodeGenOnly = 0;
232  let isAsmParserOnly = 1;
233}
234
235// Pseudo store instructions.
236class PseudoStore<string opcodestr, RegisterClass rsty = GPR>
237    : Pseudo<(outs GPR:$tmp), (ins rsty:$rs, bare_symbol:$addr), [], opcodestr, "$rs, $addr, $tmp"> {
238  let hasSideEffects = 0;
239  let mayLoad = 0;
240  let mayStore = 1;
241  let isCodeGenOnly = 0;
242  let isAsmParserOnly = 1;
243}
244
245// Instruction formats are listed in the order they appear in the RISC-V
246// instruction set manual (R, I, S, B, U, J) with sub-formats (e.g. RVInstR4,
247// RVInstRAtomic) sorted alphabetically.
248
249class RVInstR<bits<7> funct7, bits<3> funct3, RISCVOpcode opcode, dag outs,
250              dag ins, string opcodestr, string argstr>
251    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR> {
252  bits<5> rs2;
253  bits<5> rs1;
254  bits<5> rd;
255
256  let Inst{31-25} = funct7;
257  let Inst{24-20} = rs2;
258  let Inst{19-15} = rs1;
259  let Inst{14-12} = funct3;
260  let Inst{11-7} = rd;
261  let Opcode = opcode.Value;
262}
263
264class RVInstR4<bits<2> funct2, bits<3> funct3, RISCVOpcode opcode, dag outs,
265               dag ins, string opcodestr, string argstr>
266    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR4> {
267  bits<5> rs3;
268  bits<5> rs2;
269  bits<5> rs1;
270  bits<5> rd;
271
272  let Inst{31-27} = rs3;
273  let Inst{26-25} = funct2;
274  let Inst{24-20} = rs2;
275  let Inst{19-15} = rs1;
276  let Inst{14-12} = funct3;
277  let Inst{11-7} = rd;
278  let Opcode = opcode.Value;
279}
280
281class RVInstR4Frm<bits<2> funct2, RISCVOpcode opcode, dag outs, dag ins,
282                  string opcodestr, string argstr>
283    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR4> {
284  bits<5> rs3;
285  bits<5> rs2;
286  bits<5> rs1;
287  bits<3> frm;
288  bits<5> rd;
289
290  let Inst{31-27} = rs3;
291  let Inst{26-25} = funct2;
292  let Inst{24-20} = rs2;
293  let Inst{19-15} = rs1;
294  let Inst{14-12} = frm;
295  let Inst{11-7} = rd;
296  let Opcode = opcode.Value;
297}
298
299class RVInstRAtomic<bits<5> funct5, bit aq, bit rl, bits<3> funct3,
300                    RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
301                    string argstr>
302    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR> {
303  bits<5> rs2;
304  bits<5> rs1;
305  bits<5> rd;
306
307  let Inst{31-27} = funct5;
308  let Inst{26} = aq;
309  let Inst{25} = rl;
310  let Inst{24-20} = rs2;
311  let Inst{19-15} = rs1;
312  let Inst{14-12} = funct3;
313  let Inst{11-7} = rd;
314  let Opcode = opcode.Value;
315}
316
317class RVInstRFrm<bits<7> funct7, RISCVOpcode opcode, dag outs, dag ins,
318                 string opcodestr, string argstr>
319    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatR> {
320  bits<5> rs2;
321  bits<5> rs1;
322  bits<3> frm;
323  bits<5> rd;
324
325  let Inst{31-25} = funct7;
326  let Inst{24-20} = rs2;
327  let Inst{19-15} = rs1;
328  let Inst{14-12} = frm;
329  let Inst{11-7} = rd;
330  let Opcode = opcode.Value;
331}
332
333class RVInstI<bits<3> funct3, RISCVOpcode opcode, dag outs, dag ins,
334              string opcodestr, string argstr>
335    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
336  bits<12> imm12;
337  bits<5> rs1;
338  bits<5> rd;
339
340  let Inst{31-20} = imm12;
341  let Inst{19-15} = rs1;
342  let Inst{14-12} = funct3;
343  let Inst{11-7} = rd;
344  let Opcode = opcode.Value;
345}
346
347class RVInstIShift<bits<5> imm11_7, bits<3> funct3, RISCVOpcode opcode,
348                   dag outs, dag ins, string opcodestr, string argstr>
349    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
350  bits<6> shamt;
351  bits<5> rs1;
352  bits<5> rd;
353
354  let Inst{31-27} = imm11_7;
355  let Inst{26} = 0;
356  let Inst{25-20} = shamt;
357  let Inst{19-15} = rs1;
358  let Inst{14-12} = funct3;
359  let Inst{11-7} = rd;
360  let Opcode = opcode.Value;
361}
362
363class RVInstIShiftW<bits<7> imm11_5, bits<3> funct3, RISCVOpcode opcode,
364                    dag outs, dag ins, string opcodestr, string argstr>
365    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatI> {
366  bits<5> shamt;
367  bits<5> rs1;
368  bits<5> rd;
369
370  let Inst{31-25} = imm11_5;
371  let Inst{24-20} = shamt;
372  let Inst{19-15} = rs1;
373  let Inst{14-12} = funct3;
374  let Inst{11-7} = rd;
375  let Opcode = opcode.Value;
376}
377
378class RVInstS<bits<3> funct3, RISCVOpcode opcode, dag outs, dag ins,
379              string opcodestr, string argstr>
380    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatS> {
381  bits<12> imm12;
382  bits<5> rs2;
383  bits<5> rs1;
384
385  let Inst{31-25} = imm12{11-5};
386  let Inst{24-20} = rs2;
387  let Inst{19-15} = rs1;
388  let Inst{14-12} = funct3;
389  let Inst{11-7} = imm12{4-0};
390  let Opcode = opcode.Value;
391}
392
393class RVInstB<bits<3> funct3, RISCVOpcode opcode, dag outs, dag ins,
394              string opcodestr, string argstr>
395    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatB> {
396  bits<12> imm12;
397  bits<5> rs2;
398  bits<5> rs1;
399
400  let Inst{31} = imm12{11};
401  let Inst{30-25} = imm12{9-4};
402  let Inst{24-20} = rs2;
403  let Inst{19-15} = rs1;
404  let Inst{14-12} = funct3;
405  let Inst{11-8} = imm12{3-0};
406  let Inst{7} = imm12{10};
407  let Opcode = opcode.Value;
408}
409
410class RVInstU<RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
411              string argstr>
412    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatU> {
413  bits<20> imm20;
414  bits<5> rd;
415
416  let Inst{31-12} = imm20;
417  let Inst{11-7} = rd;
418  let Opcode = opcode.Value;
419}
420
421class RVInstJ<RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
422              string argstr>
423    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatJ> {
424  bits<20> imm20;
425  bits<5> rd;
426
427  let Inst{31} = imm20{19};
428  let Inst{30-21} = imm20{9-0};
429  let Inst{20} = imm20{10};
430  let Inst{19-12} = imm20{18-11};
431  let Inst{11-7} = rd;
432  let Opcode = opcode.Value;
433}
434
435//===----------------------------------------------------------------------===//
436// Instruction classes for .insn directives
437//===----------------------------------------------------------------------===//
438
439class DirectiveInsnR<dag outs, dag ins, string argstr>
440  : RVInst<outs, ins, "", "", [], InstFormatR> {
441  bits<7> opcode;
442  bits<7> funct7;
443  bits<3> funct3;
444
445  bits<5> rs2;
446  bits<5> rs1;
447  bits<5> rd;
448
449  let Inst{31-25} = funct7;
450  let Inst{24-20} = rs2;
451  let Inst{19-15} = rs1;
452  let Inst{14-12} = funct3;
453  let Inst{11-7} = rd;
454  let Opcode = opcode;
455
456  let AsmString = ".insn r " # argstr;
457}
458
459class DirectiveInsnR4<dag outs, dag ins, string argstr>
460  : RVInst<outs, ins, "", "", [], InstFormatR4> {
461  bits<7> opcode;
462  bits<2> funct2;
463  bits<3> funct3;
464
465  bits<5> rs3;
466  bits<5> rs2;
467  bits<5> rs1;
468  bits<5> rd;
469
470  let Inst{31-27} = rs3;
471  let Inst{26-25} = funct2;
472  let Inst{24-20} = rs2;
473  let Inst{19-15} = rs1;
474  let Inst{14-12} = funct3;
475  let Inst{11-7} = rd;
476  let Opcode = opcode;
477
478  let AsmString = ".insn r4 " # argstr;
479}
480
481class DirectiveInsnI<dag outs, dag ins, string argstr>
482  : RVInst<outs, ins, "", "", [], InstFormatI> {
483  bits<7> opcode;
484  bits<3> funct3;
485
486  bits<12> imm12;
487  bits<5> rs1;
488  bits<5> rd;
489
490  let Inst{31-20} = imm12;
491  let Inst{19-15} = rs1;
492  let Inst{14-12} = funct3;
493  let Inst{11-7} = rd;
494  let Opcode = opcode;
495
496  let AsmString = ".insn i " # argstr;
497}
498
499class DirectiveInsnS<dag outs, dag ins, string argstr>
500  : RVInst<outs, ins, "", "", [], InstFormatS> {
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{31-25} = imm12{11-5};
509  let Inst{24-20} = rs2;
510  let Inst{19-15} = rs1;
511  let Inst{14-12} = funct3;
512  let Inst{11-7} = imm12{4-0};
513  let Opcode = opcode;
514
515  let AsmString = ".insn s " # argstr;
516}
517
518class DirectiveInsnB<dag outs, dag ins, string argstr>
519  : RVInst<outs, ins, "", "", [], InstFormatB> {
520  bits<7> opcode;
521  bits<3> funct3;
522
523  bits<12> imm12;
524  bits<5> rs2;
525  bits<5> rs1;
526
527  let Inst{31} = imm12{11};
528  let Inst{30-25} = imm12{9-4};
529  let Inst{24-20} = rs2;
530  let Inst{19-15} = rs1;
531  let Inst{14-12} = funct3;
532  let Inst{11-8} = imm12{3-0};
533  let Inst{7} = imm12{10};
534  let Opcode = opcode;
535
536  let AsmString = ".insn b " # argstr;
537}
538
539class DirectiveInsnU<dag outs, dag ins, string argstr>
540  : RVInst<outs, ins, "", "", [], InstFormatU> {
541  bits<7> opcode;
542
543  bits<20> imm20;
544  bits<5> rd;
545
546  let Inst{31-12} = imm20;
547  let Inst{11-7} = rd;
548  let Opcode = opcode;
549
550  let AsmString = ".insn u " # argstr;
551}
552
553class DirectiveInsnJ<dag outs, dag ins, string argstr>
554  : RVInst<outs, ins, "", "", [], InstFormatJ> {
555  bits<7> opcode;
556
557  bits<20> imm20;
558  bits<5> rd;
559
560  let Inst{31-12} = imm20;
561  let Inst{11-7} = rd;
562  let Opcode = opcode;
563
564  let AsmString = ".insn j " # argstr;
565}
566