1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
|
//===-- PPCScheduleP9.td - PPC P9 Scheduling Definitions ---*- tablegen -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the itinerary class data for the POWER9 processor.
//
//===----------------------------------------------------------------------===//
include "PPCInstrInfo.td"
def P9Model : SchedMachineModel {
// The maximum number of instructions to be issued at the same time.
// While a value of 8 is technically correct since 8 instructions can be
// fetched from the instruction cache. However, only 6 instructions may be
// actually dispatched at a time.
let IssueWidth = 8;
// Load latency is 4 or 5 cycles depending on the load. This latency assumes
// that we have a cache hit. For a cache miss the load latency will be more.
// There are two instructions (lxvl, lxvll) that have a latency of 6 cycles.
// However it is not worth bumping this value up to 6 when the vast majority
// of instructions are 4 or 5 cycles.
let LoadLatency = 5;
// A total of 16 cycles to recover from a branch mispredict.
let MispredictPenalty = 16;
// Try to make sure we have at least 10 dispatch groups in a loop.
// A dispatch group is 6 instructions.
let LoopMicroOpBufferSize = 60;
// As iops are dispatched to a slice, they are held in an independent slice
// issue queue until all register sources and other dependencies have been
// resolved and they can be issued. Each of four execution slices has an
// 11-entry iop issue queue.
let MicroOpBufferSize = 44;
let CompleteModel = 1;
// Do not support SPE (Signal Processing Engine), prefixed instructions on
// Power 9, paired vector mem ops, MMA, PC relative mem ops, or instructions
// introduced in ISA 3.1.
let UnsupportedFeatures = [HasSPE, PrefixInstrs, PairedVectorMemops, MMA,
PCRelativeMemops, IsISA3_1];
}
let SchedModel = P9Model in {
// ***************** Processor Resources *****************
// Dispatcher slots:
// x0, x1, x2, and x3 are the dedicated slice dispatch ports, where each
// corresponds to one of the four execution slices.
def DISPx02 : ProcResource<2>;
def DISPx13 : ProcResource<2>;
// The xa and xb ports can be used to send an iop to either of the two slices
// of the superslice, but are restricted to iops with only two primary sources.
def DISPxab : ProcResource<2>;
// b0 and b1 are dedicated dispatch ports into the branch slice.
def DISPb01 : ProcResource<2>;
// Any non BR dispatch ports
def DISP_NBR
: ProcResGroup<[ DISPx02, DISPx13, DISPxab]>;
def DISP_SS : ProcResGroup<[ DISPx02, DISPx13]>;
// Issue Ports
// An instruction can go down one of two issue queues.
// Address Generation (AGEN) mainly for loads and stores.
// Execution (EXEC) for most other instructions.
// Some instructions cannot be run on just any issue queue and may require an
// Even or an Odd queue. The EXECE represents the even queues and the EXECO
// represents the odd queues.
def IP_AGEN : ProcResource<4>;
def IP_EXEC : ProcResource<4>;
def IP_EXECE : ProcResource<2> {
//Even Exec Ports
let Super = IP_EXEC;
}
def IP_EXECO : ProcResource<2> {
//Odd Exec Ports
let Super = IP_EXEC;
}
// Pipeline Groups
// Four ALU (Fixed Point Arithmetic) units in total. Two even, two Odd.
def ALU : ProcResource<4>;
def ALUE : ProcResource<2> {
//Even ALU pipelines
let Super = ALU;
}
def ALUO : ProcResource<2> {
//Odd ALU pipelines
let Super = ALU;
}
// Two DIV (Fixed Point Divide) units.
def DIV : ProcResource<2>;
// Four DP (Floating Point) units in total. Two even, two Odd.
def DP : ProcResource<4>;
def DPE : ProcResource<2> {
//Even DP pipelines
let Super = DP;
}
def DPO : ProcResource<2> {
//Odd DP pipelines
let Super = DP;
}
// Four LS (Load or Store) units.
def LS : ProcResource<4>;
// Two PM (Permute) units.
def PM : ProcResource<2>;
// Only one DFU (Decimal Floating Point and Quad Precision) unit.
def DFU : ProcResource<1>;
// Only one Branch unit.
def BR : ProcResource<1> {
let BufferSize = 16;
}
// Only one CY (Crypto) unit.
def CY : ProcResource<1>;
// ***************** SchedWriteRes Definitions *****************
// Dispatcher
// Dispatch Rules: '-' or 'V'
// Vector ('V') - vector iops (128-bit operand) take only one decode and
// dispatch slot but are dispatched to both the even and odd slices of a
// superslice.
def DISP_1C : SchedWriteRes<[DISP_NBR]> {
let NumMicroOps = 0;
let Latency = 1;
}
// Dispatch Rules: 'E'
// Even slice ('E')- certain operations must be sent only to an even slice.
// Also consumes odd dispatch slice slot of the same superslice at dispatch
def DISP_EVEN_1C : SchedWriteRes<[ DISPx02, DISPx13 ]> {
let NumMicroOps = 0;
let Latency = 1;
}
// Dispatch Rules: 'P'
// Paired ('P') - certain cracked and expanded iops are paired such that they
// must dispatch together to the same superslice.
def DISP_PAIR_1C : SchedWriteRes<[ DISP_SS, DISP_SS]> {
let NumMicroOps = 0;
let Latency = 1;
}
// Tuple Restricted ('R') - certain iops preclude dispatching more than one
// operation per slice for the super- slice to which they are dispatched
def DISP_3SLOTS_1C : SchedWriteRes<[DISPx02, DISPx13, DISPxab]> {
let NumMicroOps = 0;
let Latency = 1;
}
// Each execution and branch slice can receive up to two iops per cycle
def DISP_BR_1C : SchedWriteRes<[ DISPxab ]> {
let NumMicroOps = 0;
let Latency = 1;
}
// Issue Ports
def IP_AGEN_1C : SchedWriteRes<[IP_AGEN]> {
let NumMicroOps = 0;
let Latency = 1;
}
def IP_EXEC_1C : SchedWriteRes<[IP_EXEC]> {
let NumMicroOps = 0;
let Latency = 1;
}
def IP_EXECE_1C : SchedWriteRes<[IP_EXECE]> {
let NumMicroOps = 0;
let Latency = 1;
}
def IP_EXECO_1C : SchedWriteRes<[IP_EXECO]> {
let NumMicroOps = 0;
let Latency = 1;
}
//Pipeline Groups
// ALU Units
// An ALU may take either 2 or 3 cycles to complete the operation.
// However, the ALU unit is only ever busy for 1 cycle at a time and may
// receive new instructions each cycle.
def P9_ALU_2C : SchedWriteRes<[ALU]> {
let Latency = 2;
}
def P9_ALUE_2C : SchedWriteRes<[ALUE]> {
let Latency = 2;
}
def P9_ALUO_2C : SchedWriteRes<[ALUO]> {
let Latency = 2;
}
def P9_ALU_3C : SchedWriteRes<[ALU]> {
let Latency = 3;
}
def P9_ALUE_3C : SchedWriteRes<[ALUE]> {
let Latency = 3;
}
def P9_ALUO_3C : SchedWriteRes<[ALUO]> {
let Latency = 3;
}
// DIV Unit
// A DIV unit may take from 5 to 40 cycles to complete.
// Some DIV operations may keep the unit busy for up to 8 cycles.
def P9_DIV_5C : SchedWriteRes<[DIV]> {
let Latency = 5;
}
def P9_DIV_12C : SchedWriteRes<[DIV]> {
let Latency = 12;
}
def P9_DIV_16C_8 : SchedWriteRes<[DIV]> {
let ResourceCycles = [8];
let Latency = 16;
}
def P9_DIV_24C_8 : SchedWriteRes<[DIV]> {
let ResourceCycles = [8];
let Latency = 24;
}
def P9_DIV_40C_8 : SchedWriteRes<[DIV]> {
let ResourceCycles = [8];
let Latency = 40;
}
// DP Unit
// A DP unit may take from 2 to 36 cycles to complete.
// Some DP operations keep the unit busy for up to 10 cycles.
def P9_DP_5C : SchedWriteRes<[DP]> {
let Latency = 5;
}
def P9_DP_7C : SchedWriteRes<[DP]> {
let Latency = 7;
}
def P9_DPE_7C : SchedWriteRes<[DPE]> {
let Latency = 7;
}
def P9_DPO_7C : SchedWriteRes<[DPO]> {
let Latency = 7;
}
def P9_DP_22C_5 : SchedWriteRes<[DP]> {
let ResourceCycles = [5];
let Latency = 22;
}
def P9_DPO_24C_8 : SchedWriteRes<[DPO]> {
let ResourceCycles = [8];
let Latency = 24;
}
def P9_DPE_24C_8 : SchedWriteRes<[DPE]> {
let ResourceCycles = [8];
let Latency = 24;
}
def P9_DP_26C_5 : SchedWriteRes<[DP]> {
let ResourceCycles = [5];
let Latency = 22;
}
def P9_DPE_27C_10 : SchedWriteRes<[DP]> {
let ResourceCycles = [10];
let Latency = 27;
}
def P9_DPO_27C_10 : SchedWriteRes<[DP]> {
let ResourceCycles = [10];
let Latency = 27;
}
def P9_DP_33C_8 : SchedWriteRes<[DP]> {
let ResourceCycles = [8];
let Latency = 33;
}
def P9_DPE_33C_8 : SchedWriteRes<[DPE]> {
let ResourceCycles = [8];
let Latency = 33;
}
def P9_DPO_33C_8 : SchedWriteRes<[DPO]> {
let ResourceCycles = [8];
let Latency = 33;
}
def P9_DP_36C_10 : SchedWriteRes<[DP]> {
let ResourceCycles = [10];
let Latency = 36;
}
def P9_DPE_36C_10 : SchedWriteRes<[DP]> {
let ResourceCycles = [10];
let Latency = 36;
}
def P9_DPO_36C_10 : SchedWriteRes<[DP]> {
let ResourceCycles = [10];
let Latency = 36;
}
// PM Unit
// Three cycle permute operations.
def P9_PM_3C : SchedWriteRes<[PM]> {
let Latency = 3;
}
// Load and Store Units
// Loads can have 4, 5 or 6 cycles of latency.
// Stores are listed as having a single cycle of latency. This is not
// completely accurate since it takes more than 1 cycle to actually store
// the value. However, since the store does not produce a result it can be
// considered complete after one cycle.
def P9_LS_1C : SchedWriteRes<[LS]> {
let Latency = 1;
}
def P9_LS_4C : SchedWriteRes<[LS]> {
let Latency = 4;
}
def P9_LS_5C : SchedWriteRes<[LS]> {
let Latency = 5;
}
def P9_LS_6C : SchedWriteRes<[LS]> {
let Latency = 6;
}
// DFU Unit
// Some of the most expensive ops use the DFU.
// Can take from 12 cycles to 76 cycles to obtain a result.
// The unit may be busy for up to 62 cycles.
def P9_DFU_12C : SchedWriteRes<[DFU]> {
let Latency = 12;
}
def P9_DFU_23C : SchedWriteRes<[DFU]> {
let Latency = 23;
let ResourceCycles = [11];
}
def P9_DFU_24C : SchedWriteRes<[DFU]> {
let Latency = 24;
let ResourceCycles = [12];
}
def P9_DFU_37C : SchedWriteRes<[DFU]> {
let Latency = 37;
let ResourceCycles = [25];
}
def P9_DFU_58C : SchedWriteRes<[DFU]> {
let Latency = 58;
let ResourceCycles = [44];
}
def P9_DFU_76C : SchedWriteRes<[DFU]> {
let Latency = 76;
let ResourceCycles = [62];
}
// 2 or 5 cycle latencies for the branch unit.
def P9_BR_2C : SchedWriteRes<[BR]> {
let Latency = 2;
}
def P9_BR_5C : SchedWriteRes<[BR]> {
let Latency = 5;
}
// 6 cycle latency for the crypto unit
def P9_CY_6C : SchedWriteRes<[CY]> {
let Latency = 6;
}
// ***************** WriteSeq Definitions *****************
// These are combinations of the resources listed above.
// The idea is that some cracked instructions cannot be done in parallel and
// so the latencies for their resources must be added.
def P9_LoadAndALUOp_6C : WriteSequence<[P9_LS_4C, P9_ALU_2C]>;
def P9_LoadAndALUOp_7C : WriteSequence<[P9_LS_5C, P9_ALU_2C]>;
def P9_LoadAndALU2Op_7C : WriteSequence<[P9_LS_4C, P9_ALU_3C]>;
def P9_LoadAndALU2Op_8C : WriteSequence<[P9_LS_5C, P9_ALU_3C]>;
def P9_LoadAndPMOp_8C : WriteSequence<[P9_LS_5C, P9_PM_3C]>;
def P9_LoadAndLoadOp_8C : WriteSequence<[P9_LS_4C, P9_LS_4C]>;
def P9_IntDivAndALUOp_18C_8 : WriteSequence<[P9_DIV_16C_8, P9_ALU_2C]>;
def P9_IntDivAndALUOp_26C_8 : WriteSequence<[P9_DIV_24C_8, P9_ALU_2C]>;
def P9_IntDivAndALUOp_42C_8 : WriteSequence<[P9_DIV_40C_8, P9_ALU_2C]>;
def P9_StoreAndALUOp_3C : WriteSequence<[P9_LS_1C, P9_ALU_2C]>;
def P9_ALUOpAndALUOp_4C : WriteSequence<[P9_ALU_2C, P9_ALU_2C]>;
def P9_ALU2OpAndALU2Op_6C : WriteSequence<[P9_ALU_3C, P9_ALU_3C]>;
def P9_ALUOpAndALUOpAndALUOp_6C :
WriteSequence<[P9_ALU_2C, P9_ALU_2C, P9_ALU_2C]>;
def P9_DPOpAndALUOp_7C : WriteSequence<[P9_DP_5C, P9_ALU_2C]>;
def P9_DPOpAndALU2Op_10C : WriteSequence<[P9_DP_7C, P9_ALU_3C]>;
def P9_DPOpAndALU2Op_25C_5 : WriteSequence<[P9_DP_22C_5, P9_ALU_3C]>;
def P9_DPOpAndALU2Op_29C_5 : WriteSequence<[P9_DP_26C_5, P9_ALU_3C]>;
def P9_DPOpAndALU2Op_36C_8 : WriteSequence<[P9_DP_33C_8, P9_ALU_3C]>;
def P9_DPOpAndALU2Op_39C_10 : WriteSequence<[P9_DP_36C_10, P9_ALU_3C]>;
def P9_BROpAndALUOp_7C : WriteSequence<[P9_BR_5C, P9_ALU_2C]>;
// Include the resource requirements of individual instructions.
include "P9InstrResources.td"
}
|