xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Lanai/LanaiInstrFormats.td (revision ebacd8013fe5f7fdf9f6a5b286f6680dd2891036)
1//===- LanaiInstrFormats.td - Lanai 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
9class InstLanai<dag outs, dag ins, string asmstr, list<dag> pattern>
10    : Instruction {
11  field bits<32> Inst;
12  field bits<32> SoftFail = 0;
13  let Size = 4;
14
15  let Namespace = "Lanai";
16  let DecoderNamespace = "Lanai";
17
18  bits<4> Opcode;
19  let Inst{31 - 28} = Opcode;
20
21  dag OutOperandList = outs;
22  dag InOperandList = ins;
23  let AsmString = asmstr;
24  let Pattern = pattern;
25}
26
27//------------------------------------------------------------------------------
28// Register Immediate (RI)
29//------------------------------------------------------------------------------
30// Encoding:
31//           -----------------------------------------------------------------
32//           |0.A.A.A| . . . . | . . . . |F.H| . . . . . . . . . . . . . . . |
33//           -----------------------------------------------------------------
34//            opcode     Rd        Rs1                constant (16)
35//
36// Action:
37//           Rd <- Rs1 op constant
38//
39// Except for shift instructions, `H' determines whether the constant
40// is in the high (1) or low (0) word.  The other halfword is 0x0000,
41// except for the `AND' instruction (`AAA' = 100), for which the other
42// halfword is 0xFFFF, and shifts (`AAA' = 111), for which the constant is
43// sign extended.
44//
45// `F' determines whether the instruction modifies (1) or does not
46// modify (0) the program flags.
47//
48// `AAA' specifies the operation: `add' (000), `addc' (001), `sub'
49// (010), `subb' (011), `and' (100), `or' (101), `xor' (110), or `shift'
50// (111).  For the shift, `H' specifies a logical (0) or arithmetic (1)
51// shift.  The amount and direction of the shift are determined by the
52// sign extended constant interpreted as a two's complement number.  The
53// shift operation is defined only for the range of:
54//      31 ... 0 -1 ... -31
55//      \      / \        /
56//        left     right
57//        shift    shift
58//
59// If and only if the `F' bit is 1, RI instructions modify the
60// condition bits, `Z' (Zero), `N' (Negative), `V' (oVerflow), and `C'
61// (Carry), according to the result.  If the flags are updated, they are
62// updated as follows:
63// `Z'
64//      is set if the result is zero and cleared otherwise.
65//
66// `N'
67//      is set to the most significant bit of the result.
68//
69// `V'
70//      For arithmetic instructions (`add', `addc', `sub', `subb') `V' is
71//      set if the sign (most significant) bits of the input operands are
72//      the same but different from the sign bit of the result and cleared
73//      otherwise.  For other RI instructions, `V' is cleared.
74//
75// `C'
76//      For arithmetic instructions, `C' is set/cleared if there is/is_not
77//      a carry generated out of the most significant when performing the
78//      twos-complement addition (`sub(a,b) == a + ~b + 1', `subb(a,b) ==
79//      a + ~b + `C'').  For left shifts, `C' is set to the least
80//      significant bit discarded by the shift operation.  For all other
81//      operations, `C' is cleared.
82//
83// A Jump is accomplished by `Rd' being `pc', and it has one shadow.
84//
85// The all-0s word is the instruction `R0 <- R0 + 0', which is a no-op.
86class InstRI<bits<3> op, dag outs, dag ins, string asmstr,
87             list<dag> pattern>
88    : InstLanai<outs, ins, asmstr, pattern>, Sched<[WriteALU]> {
89  let Itinerary = IIC_ALU;
90  bits<5> Rd;
91  bits<5> Rs1;
92  bit F;
93  bit H;
94  bits<16> imm16;
95
96  let Opcode{3} = 0;
97  let Opcode{2 - 0} = op;
98  let Inst{27 - 23} = Rd;
99  let Inst{22 - 18} = Rs1;
100  let Inst{17} = F;
101  let Inst{16} = H;
102  let Inst{15 - 0} = imm16;
103}
104
105//------------------------------------------------------------------------------
106// Register Register (RR)
107//------------------------------------------------------------------------------
108// Encoding:
109//           -----------------------------------------------------------------
110//           |1.1.0.0| . . . . | . . . . |F.I| . . . . |B.B.B|J.J.J.J.J|D.D.D|
111//           -----------------------------------------------------------------
112//            opcode     Rd        Rs1           Rs2   \       operation     /
113//
114// Action:
115//           `Rd <- Rs1 op Rs2' iff condition DDDI is true.
116//
117// `DDDI' is as described for the BR instruction.
118//
119// `F' determines whether the instruction modifies (1) or does not
120// modify (0) the program flags.
121//
122// `BBB' determines the operation: `add' (000), `addc' (001), `sub'
123// (010), `subb' (011), `and' (100), `or' (101), `xor' (110), or "special"
124// (111).  The `JJJJJ' field is irrelevant except for special.
125//
126// `JJJJJ' determines which special operation is performed.  `10---'
127// is a logical shift, and `11---' is an arithmetic shift, and ‘00000` is
128// the SELECT operation.  The amount and direction of the shift are
129// determined by the contents of `Rs2' interpreted as a two's complement
130// number (in the same way as shifts in the Register-Immediate
131// instructions in *Note RI::).  For the SELECT operation, Rd gets Rs1 if
132// condition DDDI is true, Rs2 otherwise. All other `JJJJJ' combinations
133// are reserved for instructions that may be defined in the future.
134//
135// If the `F' bit is 1, RR instructions modify the condition bits, `Z'
136// (Zero), `N' (Negative), `V' (oVerflow), and `C' (Carry), according to
137// the result.  All RR instructions modify the `Z', `N', and `V' flags.
138// Except for arithmetic instructions (`add', `addc', `sub', `subb'), `V'
139// is cleared.  Only arithmetic instructions and shifts modify `C'. Right
140// shifts clear C.
141//
142// DDDI is as described in the table for the BR instruction and only used for
143// the select instruction.
144//
145// A Jump is accomplished by `Rd' being `pc', and it has one shadow.
146class InstRR<bits<3> op, dag outs, dag ins, string asmstr,
147             list<dag> pattern>
148    : InstLanai<outs, ins, asmstr, pattern>, Sched<[WriteALU]> {
149  let Itinerary = IIC_ALU;
150  bits<5> Rd;
151  bits<5> Rs1;
152  bits<5> Rs2;
153  bit F;
154  bits<4> DDDI;
155  bits<5> JJJJJ;
156
157  let Opcode = 0b1100;
158  let Inst{27 - 23} = Rd;
159  let Inst{22 - 18} = Rs1;
160  let Inst{17} = F;
161  let Inst{16} = DDDI{0};
162  let Inst{15 - 11} = Rs2;
163  let Inst{10 - 8} = op;
164  let Inst{7 - 3} = JJJJJ;
165  let Inst{2 - 0} = DDDI{3 - 1};
166}
167
168//------------------------------------------------------------------------------
169// Register Memory (RM)
170//------------------------------------------------------------------------------
171// Encoding:
172//          -----------------------------------------------------------------
173//          |1.0.0.S| . . . . | . . . . |P.Q| . . . . . . . . . . . . . . . |
174//          -----------------------------------------------------------------
175//           opcode     Rd        Rs1                 constant (16)
176//
177// Action:
178//        Rd <- Memory(ea)      (Load)    see below for the
179//        Memory(ea) <- Rd      (Store)   definition of ea.
180//
181// `S' determines whether the instruction is a Load (0) or a Store (1).
182// Loads appear in Rd one cycle after this instruction executes.  If the
183// following instruction reads Rd, that instruction will be delayed by 1
184// clock cycle.
185//
186//   PQ      operation
187//   --      ------------------------------------------
188//   00      ea = Rs1
189//   01      ea = Rs1,             Rs1 <- Rs1 + constant
190//   10      ea = Rs1 + constant
191//   11      ea = Rs1 + constant,  Rs1 <- Rs1 + constant
192//
193// The constant is sign-extended for this instruction.
194//
195// A Jump is accomplished by `Rd' being `pc', and it has *two* delay slots.
196class InstRM<bit S, dag outs, dag ins, string asmstr, list<dag> pattern>
197    : InstLanai<outs, ins, asmstr, pattern> {
198  bits<5> Rd;
199  bits<5> Rs1;
200  bit P;
201  bit Q;
202  bits<16> imm16;
203  // Dummy variables to allow multiclass definition of RM and RRM
204  bits<2> YL;
205  bit E;
206
207  let Opcode{3 - 1} = 0b100;
208  let Opcode{0} = S;
209  let Inst{27 - 23} = Rd;
210  let Inst{22 - 18} = Rs1;
211  let Inst{17} = P;
212  let Inst{16} = Q;
213  let Inst{15 - 0} = imm16;
214
215  let PostEncoderMethod = "adjustPqBitsRmAndRrm";
216}
217
218//------------------------------------------------------------------------------
219// Register Register Memory (RRM)
220//------------------------------------------------------------------------------
221// Encoding:
222//           -----------------------------------------------------------------
223//           |1.0.1.S| . . . . | . . . . |P.Q| . . . . |B.B.B|J.J.J.J.J|Y.L.E|
224//           -----------------------------------------------------------------
225//            opcode     Rd        Rs1           Rs2   \       operation     /
226//
227// Action:
228//           Rd <- Memory(ea)      (Load)    see below for the
229//           Memory(ea) <- Rd      (Store)   definition of ea.
230//
231// The RRM instruction is identical to the RM (*note RM::.) instruction
232// except that:
233//
234// 1. `Rs1 + constant' is replaced with `Rs1 op Rs2', where `op' is
235//    determined in the same way as in the RR instruction (*note RR::.)
236//    and
237//
238// 2. part-word memory accesses are allowed as specified below.
239//
240//    If `BBB' != 111 (i.e.: For all but shift operations):
241//        If `YLE' = 01- => fuLl-word memory access
242//        If `YLE' = 00- => half-word memory access
243//        If `YLE' = 10- => bYte memory access
244//        If `YLE' = --1 => loads are zEro extended
245//        If `YLE' = --0 => loads are sign extended
246//
247//    If `BBB' = 111 (For shift operations):
248//        fullword memory access are performed.
249//
250// All part-word loads write the least significant part of the
251// destination register with the higher-order bits zero- or sign-extended.
252// All part-word stores store the least significant part-word of the
253// source register in the destination memory location.
254//
255// A Jump is accomplished by `Rd' being `pc', and it has *two* delay slots.
256class InstRRM<bit S, dag outs, dag ins, string asmstr,
257              list<dag> pattern>
258    : InstLanai<outs, ins, asmstr, pattern> {
259  bits<5> Rd;
260  bits<5> Rs1;
261  bits<5> Rs2;
262  bit P;
263  bit Q;
264  bits<3> BBB;
265  bits<5> JJJJJ;
266  bits<2> YL;
267  bit E;
268
269  let Opcode{3 - 1} = 0b101;
270  let Opcode{0} = S;
271  let Inst{27 - 23} = Rd;
272  let Inst{22 - 18} = Rs1;
273  let Inst{17} = P;
274  let Inst{16} = Q;
275  let Inst{15 - 11} = Rs2;
276  let Inst{10 - 8} = BBB;
277  let Inst{7 - 3} = JJJJJ;
278  let Inst{2 - 1} = YL;
279  let Inst{0} = E;
280
281  let PostEncoderMethod = "adjustPqBitsRmAndRrm";
282}
283
284//------------------------------------------------------------------------------
285// Conditional Branch (BR)
286//------------------------------------------------------------------------------
287// Encoding:
288//           -----------------------------------------------------------------
289//           |1.1.1.0|D.D.D| . . . . . . . . . . . . . . . . . . . . . . |0.I|
290//           -----------------------------------------------------------------
291//            opcode condition                   constant (23)
292//
293// Action:
294//            if (condition) { `pc' <- 4*(zero-extended constant) }
295//
296// The BR instruction is an absolute branch.
297// The constant is scaled as shown by its position in the instruction word such
298// that it specifies word-aligned addresses in the range [0,2^25-4]
299//
300// The `DDDI' field selects the condition that causes the branch to be taken.
301// (the `I' (Invert sense) bit inverts the sense of the condition):
302//
303//   DDDI  logical function                        [code, used for...]
304//   ----  --------------------------------------  ------------------------
305//   0000  1                                       [T, true]
306//   0001  0                                       [F, false]
307//   0010  C AND Z'                                [HI, high]
308//   0011  C' OR Z                                 [LS, low or same]
309//   0100  C'                                      [CC, carry cleared]
310//   0101  C                                       [CS, carry set]
311//   0110  Z'                                      [NE, not equal]
312//   0111  Z                                       [EQ, equal]
313//   1000  V'                                      [VC, oVerflow cleared]
314//   1001  V                                       [VS, oVerflow set]
315//   1010  N'                                      [PL, plus]
316//   1011  N                                       [MI, minus]
317//   1100  (N AND V) OR (N' AND V')                [GE, greater than or equal]
318//   1101  (N AND V') OR (N' AND V)                [LT, less than]
319//   1110  (N AND V AND Z') OR (N' AND V' AND Z')  [GT, greater than]
320//   1111  (Z) OR (N AND V') OR (N' AND V)         [LE, less than or equal]
321//
322// If the branch is not taken, the BR instruction is a no-op.  If the branch is
323// taken, the processor starts executing instructions at the branch target
324// address *after* the processor has executed one more instruction.  That is,
325// the branch has one “branch delay slot”.  Be very careful if you find yourself
326// wanting to put a branch in a branch delays slot!
327class InstBR<dag outs, dag ins, string asmstr, list<dag> pattern>
328    : InstLanai<outs, ins, asmstr, pattern> {
329  let Itinerary = IIC_ALU;
330  bits<25> addr;
331  bits<4> DDDI;
332
333  let Opcode = 0b1110;
334  let Inst{27 - 25} = DDDI{3 - 1};
335  let Inst{24 - 0} = addr;
336  // These instructions overwrite the last two address bits (which are assumed
337  // and ensured to be 0).
338  let Inst{1} = 0;
339  let Inst{0} = DDDI{0};
340}
341
342//------------------------------------------------------------------------------
343// Conditional Branch Relative (BRR)
344//------------------------------------------------------------------------------
345// Encoding:
346//           -----------------------------------------------------------------
347//           |1.1.1.0|D.D.D|1|-| . . . . |-.-| . . . . . . . . . . . . . |1.I|
348//           -----------------------------------------------------------------
349//            opcode condition     Rs1           constant (14)
350// Action:
351//           if (condition) { ‘pc’ <- Rs1 + 4*sign-extended constant) }
352//
353// BRR behaves like BR, except the branch target address is a 16-bit PC relative
354// offset.
355class InstBRR<dag outs, dag ins, string asmstr, list<dag> pattern>
356    : InstLanai<outs, ins, asmstr, pattern> {
357  bits<4> DDDI;
358  bits<5> Rs1;
359  bits<16> imm16;
360
361  let Opcode = 0b1110;
362  let Inst{27 - 25} = DDDI{3 - 1};
363  let Inst{24} = 1;
364  let Inst{22 - 18} = Rs1;
365  let Inst{17 - 16} = 0;
366  let Inst{15 - 0} = imm16;
367  // Overwrite last two bits which have to be zero
368  let Inst{1} = 1;
369  let Inst{0} = DDDI{0};
370
371  // Set don't cares to zero
372  let Inst{23} = 0;
373}
374
375//------------------------------------------------------------------------------
376// Conditional Set (SCC)
377//------------------------------------------------------------------------------
378// Encoding:
379//           -----------------------------------------------------------------
380//           |1.1.1.0|D.D.D|0.-| . . . . |-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-|1.I|
381//           -----------------------------------------------------------------
382//            opcode condition     Rs1
383//
384// Action:
385//       Rs1 <- logical function result
386//
387// SCC sets dst_reg to the boolean result of computing the logical function
388// specified by DDDI, as described in the table for the BR instruction.
389class InstSCC<dag outs, dag ins, string asmstr,
390              list<dag> pattern>
391    : InstLanai<outs, ins, asmstr, pattern> {
392  let Itinerary = IIC_ALU;
393  bits<5> Rs1; // dst_reg in documentation
394  bits<4> DDDI;
395
396  let Opcode = 0b1110;
397  let Inst{27 - 25} = DDDI{3 - 1};
398  let Inst{24} = 0;
399  let Inst{22 - 18} = Rs1;
400  let Inst{1} = 1;
401  let Inst{0} = DDDI{0};
402
403  // Set don't cares to zero
404  let Inst{23} = 0;
405  let Inst{17 - 2} = 0;
406}
407
408//------------------------------------------------------------------------------
409// Special Load/Store (SLS)
410//------------------------------------------------------------------------------
411//
412// Encoding:
413//           -----------------------------------------------------------------
414//           |1.1.1.1| . . . . | . . . . |0.S| . . . . . . . . . . . . . . . |
415//           -----------------------------------------------------------------
416//            opcode     Rd    addr 5msb's            address 16 lsb's
417//
418// Action:
419//           If S = 0 (LOAD):   Rd <- Memory(address);
420//           If S = 1 (STORE):  Memory(address) <- Rd
421//
422// The timing is the same as for RM (*note RM::.) and RRM (*note
423// RRM::.) instructions.  The two low-order bits of the 21-bit address are
424// ignored.  The address is zero extended.  Fullword memory accesses are
425// performed.
426class InstSLS<bit S, dag outs, dag ins, string asmstr, list<dag> pattern>
427    : InstLanai<outs, ins, asmstr, pattern> {
428  bits<5> Rd;
429  bits<5> msb;
430  bits<16> lsb;
431
432  let Opcode = 0b1111;
433  let Inst{27 - 23} = Rd;
434  let Inst{22 - 18} = msb;
435  let Inst{17} = 0;
436  let Inst{16} = S;
437  let Inst{15 - 0} = lsb;
438}
439
440//------------------------------------------------------------------------------
441// Special Load Immediate (SLI)
442//------------------------------------------------------------------------------
443// Encoding:
444//           -----------------------------------------------------------------
445//           |1.1.1.1| . . . . | . . . . |1.0| . . . . . . . . . . . . . . . |
446//           -----------------------------------------------------------------
447//            opcode     Rd    const 5msb's          constant 16 lsb's
448//
449// Action:
450//           Rd <- constant
451//
452// The 21-bit constant is zero-extended.  The timing is the same as the
453// RM instruction (*note RM::.).
454class InstSLI<dag outs, dag ins, string asmstr, list<dag> pattern>
455    : InstLanai<outs, ins, asmstr, pattern> {
456  bits<5> Rd;
457  bits<5> msb;
458  bits<16> lsb;
459
460  let Opcode = 0b1111;
461  let Inst{27 - 23} = Rd;
462  let Inst{22 - 18} = msb;
463  let Inst{17} = 1;
464  let Inst{16} = 0;
465  let Inst{15 - 0} = lsb;
466}
467
468//------------------------------------------------------------------------------
469// Special Part-Word Load/Store (SPLS)
470//------------------------------------------------------------------------------
471// Encoding:
472//        -----------------------------------------------------------------
473//        |1.1.1.1| . . . . | . . . . |1.1.0.Y.S.E.P.Q| . . . . . . . . . |
474//        -----------------------------------------------------------------
475//         opcode     Rd        Rs1                       constant (10)
476//
477// Action:
478//        If `YS' = 11  (bYte     Store):
479//             Memory(ea) <- (least significant byte of Rr)
480//        If `YS' = 01  (halfword Store):
481//             Memory(ea) <- (least significant half-word of Rr)
482//        If `YS' = 10  (bYte     load):  Rr <- Memory(ea)
483//        If `YS' = 00  (halfword load):  Rr <- Memory(ea)
484//             [Note: here ea is determined as in the RM instruction. ]
485//        If `SE' = 01 then the value is zEro extended
486//             before being loaded into Rd.
487//        If `SE' = 00 then the value is sign extended
488//             before being loaded into Rd.
489//
490// `P' and `Q' are used to determine `ea' as in the RM instruction. The
491// constant is sign extended.  The timing is the same as the RM and RRM
492// instructions.  *Note RM:: and *Note RRM::.
493//
494// All part-word loads write the part-word into the least significant
495// part of the destination register, with the higher-order bits zero- or
496// sign-extended.  All part-word stores store the least significant
497// part-word of the source register into the destination memory location.
498class InstSPLS<dag outs, dag ins, string asmstr,
499               list<dag> pattern>
500    : InstLanai<outs, ins, asmstr, pattern> {
501  bits<5> Rd;
502  bits<5> Rs1;
503  bits<5> msb;
504  bit Y;
505  bit S;
506  bit E;
507  bit P;
508  bit Q;
509  bits<10> imm10;
510
511  let Opcode = 0b1111;
512  let Inst{27 - 23} = Rd;
513  let Inst{22 - 18} = Rs1;
514  let Inst{17 - 15} = 0b110;
515  let Inst{14} = Y;
516  let Inst{13} = S;
517  let Inst{12} = E;
518  let Inst{11} = P;
519  let Inst{10} = Q;
520  let Inst{9 - 0} = imm10;
521
522  let PostEncoderMethod = "adjustPqBitsSpls";
523}
524
525//------------------------------------------------------------------------------
526// Special instructions (popc, leadz, trailz)
527//------------------------------------------------------------------------------
528// Encoding:
529//         -----------------------------------------------------------------
530//         |1.1.0.1|    Rd   |   Rs1   |F.-| . . . . | . . | . . . . | OP  |
531//         -----------------------------------------------------------------
532//          opcode      Rd       Rs1
533// Action:
534//         Rd <- Perform action encoded in OP on Rs1
535//   OP is one of:
536//      0b001 POPC   Population count;
537//      0b010 LEADZ  Count number of leading zeros;
538//      0b011 TRAILZ Count number of trailing zeros;
539class InstSpecial<bits<3> op, dag outs, dag ins, string asmstr,
540                  list<dag> pattern> : InstLanai<outs, ins, asmstr,
541                  pattern>, Sched<[WriteALU]> {
542  let Itinerary = IIC_ALU;
543  bit F;
544  bits<5> Rd;
545  bits<5> Rs1;
546
547  let Opcode = 0b1101;
548  let Inst{27 - 23} = Rd;
549  let Inst{22 - 18} = Rs1;
550  let Inst{17} = F;
551  let Inst{16 - 3} = 0;
552  let Inst{2 - 0} = op;
553}
554
555// Pseudo instructions
556class Pseudo<dag outs, dag ins, string asmstr, list<dag> pattern>
557    : InstLanai<outs, ins, asmstr, pattern> {
558  let Inst{15 - 0} = 0;
559  let isPseudo = 1;
560}
561