1 | // Licensed to the .NET Foundation under one or more agreements. |
2 | // The .NET Foundation licenses this file to you under the MIT license. |
3 | // See the LICENSE file in the project root for more information. |
4 | |
5 | /*XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
6 | XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
7 | XX XX |
8 | XX Lowering for AMD64, x86 XX |
9 | XX XX |
10 | XX This encapsulates all the logic for lowering trees for the AMD64 XX |
11 | XX architecture. For a more detailed view of what is lowering, please XX |
12 | XX take a look at Lower.cpp XX |
13 | XX XX |
14 | XX XX |
15 | XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
16 | XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX |
17 | */ |
18 | |
19 | #include "jitpch.h" |
20 | #ifdef _MSC_VER |
21 | #pragma hdrstop |
22 | #endif |
23 | |
24 | #ifdef _TARGET_XARCH_ // This file is only used for xarch |
25 | |
26 | #include "jit.h" |
27 | #include "sideeffects.h" |
28 | #include "lower.h" |
29 | |
30 | // xarch supports both ROL and ROR instructions so no lowering is required. |
31 | void Lowering::LowerRotate(GenTree* tree) |
32 | { |
33 | ContainCheckShiftRotate(tree->AsOp()); |
34 | } |
35 | |
36 | //------------------------------------------------------------------------ |
37 | // LowerStoreLoc: Lower a store of a lclVar |
38 | // |
39 | // Arguments: |
40 | // storeLoc - the local store (GT_STORE_LCL_FLD or GT_STORE_LCL_VAR) |
41 | // |
42 | // Notes: |
43 | // This involves: |
44 | // - Handling of contained immediates. |
45 | // - Widening operations of unsigneds. |
46 | |
47 | void Lowering::LowerStoreLoc(GenTreeLclVarCommon* storeLoc) |
48 | { |
49 | // Try to widen the ops if they are going into a local var. |
50 | if ((storeLoc->gtOper == GT_STORE_LCL_VAR) && (storeLoc->gtOp1->gtOper == GT_CNS_INT)) |
51 | { |
52 | GenTreeIntCon* con = storeLoc->gtOp1->AsIntCon(); |
53 | ssize_t ival = con->gtIconVal; |
54 | |
55 | unsigned varNum = storeLoc->gtLclNum; |
56 | LclVarDsc* varDsc = comp->lvaTable + varNum; |
57 | |
58 | if (varDsc->lvIsSIMDType()) |
59 | { |
60 | noway_assert(storeLoc->gtType != TYP_STRUCT); |
61 | } |
62 | unsigned size = genTypeSize(storeLoc); |
63 | // If we are storing a constant into a local variable |
64 | // we extend the size of the store here |
65 | if ((size < 4) && !varTypeIsStruct(varDsc)) |
66 | { |
67 | if (!varTypeIsUnsigned(varDsc)) |
68 | { |
69 | if (genTypeSize(storeLoc) == 1) |
70 | { |
71 | if ((ival & 0x7f) != ival) |
72 | { |
73 | ival = ival | 0xffffff00; |
74 | } |
75 | } |
76 | else |
77 | { |
78 | assert(genTypeSize(storeLoc) == 2); |
79 | if ((ival & 0x7fff) != ival) |
80 | { |
81 | ival = ival | 0xffff0000; |
82 | } |
83 | } |
84 | } |
85 | |
86 | // A local stack slot is at least 4 bytes in size, regardless of |
87 | // what the local var is typed as, so auto-promote it here |
88 | // unless it is a field of a promoted struct |
89 | // TODO-XArch-CQ: if the field is promoted shouldn't we also be able to do this? |
90 | if (!varDsc->lvIsStructField) |
91 | { |
92 | storeLoc->gtType = TYP_INT; |
93 | con->SetIconValue(ival); |
94 | } |
95 | } |
96 | } |
97 | if (storeLoc->OperIs(GT_STORE_LCL_FLD)) |
98 | { |
99 | // We should only encounter this for lclVars that are lvDoNotEnregister. |
100 | verifyLclFldDoNotEnregister(storeLoc->gtLclNum); |
101 | } |
102 | ContainCheckStoreLoc(storeLoc); |
103 | } |
104 | |
105 | //------------------------------------------------------------------------ |
106 | // LowerStoreIndir: Determine addressing mode for an indirection, and whether operands are contained. |
107 | // |
108 | // Arguments: |
109 | // node - The indirect store node (GT_STORE_IND) of interest |
110 | // |
111 | // Return Value: |
112 | // None. |
113 | // |
114 | void Lowering::LowerStoreIndir(GenTreeIndir* node) |
115 | { |
116 | // Mark all GT_STOREIND nodes to indicate that it is not known |
117 | // whether it represents a RMW memory op. |
118 | node->AsStoreInd()->SetRMWStatusDefault(); |
119 | |
120 | if (!varTypeIsFloating(node)) |
121 | { |
122 | // Perform recognition of trees with the following structure: |
123 | // StoreInd(addr, BinOp(expr, GT_IND(addr))) |
124 | // to be able to fold this into an instruction of the form |
125 | // BINOP [addr], register |
126 | // where register is the actual place where 'expr' is computed. |
127 | // |
128 | // SSE2 doesn't support RMW form of instructions. |
129 | if (LowerRMWMemOp(node)) |
130 | { |
131 | return; |
132 | } |
133 | } |
134 | ContainCheckStoreIndir(node); |
135 | } |
136 | |
137 | //------------------------------------------------------------------------ |
138 | // LowerBlockStore: Set block store type |
139 | // |
140 | // Arguments: |
141 | // blkNode - The block store node of interest |
142 | // |
143 | // Return Value: |
144 | // None. |
145 | // |
146 | void Lowering::LowerBlockStore(GenTreeBlk* blkNode) |
147 | { |
148 | GenTree* dstAddr = blkNode->Addr(); |
149 | unsigned size = blkNode->gtBlkSize; |
150 | GenTree* source = blkNode->Data(); |
151 | Compiler* compiler = comp; |
152 | GenTree* srcAddrOrFill = nullptr; |
153 | bool isInitBlk = blkNode->OperIsInitBlkOp(); |
154 | |
155 | if (!isInitBlk) |
156 | { |
157 | // CopyObj or CopyBlk |
158 | if ((blkNode->OperGet() == GT_STORE_OBJ) && ((blkNode->AsObj()->gtGcPtrCount == 0) || blkNode->gtBlkOpGcUnsafe)) |
159 | { |
160 | blkNode->SetOper(GT_STORE_BLK); |
161 | } |
162 | if (source->gtOper == GT_IND) |
163 | { |
164 | srcAddrOrFill = blkNode->Data()->gtGetOp1(); |
165 | } |
166 | } |
167 | |
168 | if (isInitBlk) |
169 | { |
170 | GenTree* initVal = source; |
171 | if (initVal->OperIsInitVal()) |
172 | { |
173 | initVal->SetContained(); |
174 | initVal = initVal->gtGetOp1(); |
175 | } |
176 | srcAddrOrFill = initVal; |
177 | // If we have an InitBlk with constant block size we can optimize several ways: |
178 | // a) If the size is smaller than a small memory page but larger than INITBLK_UNROLL_LIMIT bytes |
179 | // we use rep stosb since this reduces the register pressure in LSRA and we have |
180 | // roughly the same performance as calling the helper. |
181 | // b) If the size is <= INITBLK_UNROLL_LIMIT bytes and the fill byte is a constant, |
182 | // we can speed this up by unrolling the loop using SSE2 stores. The reason for |
183 | // this threshold is because our last investigation (Fall 2013), more than 95% of initblks |
184 | // in our framework assemblies are actually <= INITBLK_UNROLL_LIMIT bytes size, so this is the |
185 | // preferred code sequence for the vast majority of cases. |
186 | |
187 | // This threshold will decide from using the helper or let the JIT decide to inline |
188 | // a code sequence of its choice. |
189 | unsigned helperThreshold = max(INITBLK_STOS_LIMIT, INITBLK_UNROLL_LIMIT); |
190 | |
191 | // TODO-X86-CQ: Investigate whether a helper call would be beneficial on x86 |
192 | if (size != 0 && size <= helperThreshold) |
193 | { |
194 | // Always favor unrolling vs rep stos. |
195 | if (size <= INITBLK_UNROLL_LIMIT && initVal->IsCnsIntOrI()) |
196 | { |
197 | // The fill value of an initblk is interpreted to hold a |
198 | // value of (unsigned int8) however a constant of any size |
199 | // may practically reside on the evaluation stack. So extract |
200 | // the lower byte out of the initVal constant and replicate |
201 | // it to a larger constant whose size is sufficient to support |
202 | // the largest width store of the desired inline expansion. |
203 | |
204 | ssize_t fill = initVal->gtIntCon.gtIconVal & 0xFF; |
205 | #ifdef _TARGET_AMD64_ |
206 | if (size < REGSIZE_BYTES) |
207 | { |
208 | initVal->gtIntCon.gtIconVal = 0x01010101 * fill; |
209 | } |
210 | else |
211 | { |
212 | initVal->gtIntCon.gtIconVal = 0x0101010101010101LL * fill; |
213 | initVal->gtType = TYP_LONG; |
214 | if ((fill == 0) && ((size & 0xf) == 0)) |
215 | { |
216 | MakeSrcContained(blkNode, source); |
217 | } |
218 | } |
219 | #else // !_TARGET_AMD64_ |
220 | initVal->gtIntCon.gtIconVal = 0x01010101 * fill; |
221 | #endif // !_TARGET_AMD64_ |
222 | |
223 | if ((fill == 0) && ((size & 0xf) == 0)) |
224 | { |
225 | MakeSrcContained(blkNode, source); |
226 | } |
227 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindUnroll; |
228 | } |
229 | else |
230 | { |
231 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindRepInstr; |
232 | } |
233 | } |
234 | else |
235 | { |
236 | #ifdef _TARGET_AMD64_ |
237 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindHelper; |
238 | #else // !_TARGET_AMD64_ |
239 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindRepInstr; |
240 | #endif // !_TARGET_AMD64_ |
241 | } |
242 | } |
243 | else |
244 | { |
245 | if (blkNode->gtOper == GT_STORE_OBJ) |
246 | { |
247 | // CopyObj |
248 | |
249 | GenTreeObj* cpObjNode = blkNode->AsObj(); |
250 | |
251 | unsigned slots = cpObjNode->gtSlots; |
252 | |
253 | #ifdef DEBUG |
254 | // CpObj must always have at least one GC-Pointer as a member. |
255 | assert(cpObjNode->gtGcPtrCount > 0); |
256 | |
257 | assert(dstAddr->gtType == TYP_BYREF || dstAddr->gtType == TYP_I_IMPL); |
258 | |
259 | CORINFO_CLASS_HANDLE clsHnd = cpObjNode->gtClass; |
260 | size_t classSize = comp->info.compCompHnd->getClassSize(clsHnd); |
261 | size_t blkSize = roundUp(classSize, TARGET_POINTER_SIZE); |
262 | |
263 | // Currently, the EE always round up a class data structure so |
264 | // we are not handling the case where we have a non multiple of pointer sized |
265 | // struct. This behavior may change in the future so in order to keeps things correct |
266 | // let's assert it just to be safe. Going forward we should simply |
267 | // handle this case. |
268 | assert(classSize == blkSize); |
269 | assert((blkSize / TARGET_POINTER_SIZE) == slots); |
270 | assert(cpObjNode->HasGCPtr()); |
271 | #endif |
272 | |
273 | bool IsRepMovsProfitable = false; |
274 | |
275 | // If the destination is not on the stack, let's find out if we |
276 | // can improve code size by using rep movsq instead of generating |
277 | // sequences of movsq instructions. |
278 | if (!dstAddr->OperIsLocalAddr()) |
279 | { |
280 | // Let's inspect the struct/class layout and determine if it's profitable |
281 | // to use rep movsq for copying non-gc memory instead of using single movsq |
282 | // instructions for each memory slot. |
283 | unsigned i = 0; |
284 | BYTE* gcPtrs = cpObjNode->gtGcPtrs; |
285 | |
286 | do |
287 | { |
288 | unsigned nonGCSlots = 0; |
289 | // Measure a contiguous non-gc area inside the struct and note the maximum. |
290 | while (i < slots && gcPtrs[i] == TYPE_GC_NONE) |
291 | { |
292 | nonGCSlots++; |
293 | i++; |
294 | } |
295 | |
296 | while (i < slots && gcPtrs[i] != TYPE_GC_NONE) |
297 | { |
298 | i++; |
299 | } |
300 | |
301 | if (nonGCSlots >= CPOBJ_NONGC_SLOTS_LIMIT) |
302 | { |
303 | IsRepMovsProfitable = true; |
304 | break; |
305 | } |
306 | } while (i < slots); |
307 | } |
308 | else if (slots >= CPOBJ_NONGC_SLOTS_LIMIT) |
309 | { |
310 | IsRepMovsProfitable = true; |
311 | } |
312 | |
313 | // There are two cases in which we need to materialize the |
314 | // struct size: |
315 | // a) When the destination is on the stack we don't need to use the |
316 | // write barrier, we can just simply call rep movsq and get a win in codesize. |
317 | // b) If we determine we have contiguous non-gc regions in the struct where it's profitable |
318 | // to use rep movsq instead of a sequence of single movsq instructions. According to the |
319 | // Intel Manual, the sweet spot for small structs is between 4 to 12 slots of size where |
320 | // the entire operation takes 20 cycles and encodes in 5 bytes (moving RCX, and calling rep movsq). |
321 | if (IsRepMovsProfitable) |
322 | { |
323 | // We need the size of the contiguous Non-GC-region to be in RCX to call rep movsq. |
324 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindRepInstr; |
325 | } |
326 | else |
327 | { |
328 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindUnroll; |
329 | } |
330 | } |
331 | else |
332 | { |
333 | assert((blkNode->OperGet() == GT_STORE_BLK) || (blkNode->OperGet() == GT_STORE_DYN_BLK)); |
334 | // CopyBlk |
335 | // In case of a CpBlk with a constant size and less than CPBLK_MOVS_LIMIT size |
336 | // we can use rep movs to generate code instead of the helper call. |
337 | |
338 | // This threshold will decide between using the helper or let the JIT decide to inline |
339 | // a code sequence of its choice. |
340 | unsigned helperThreshold = max(CPBLK_MOVS_LIMIT, CPBLK_UNROLL_LIMIT); |
341 | |
342 | // TODO-X86-CQ: Investigate whether a helper call would be beneficial on x86 |
343 | if ((size != 0) && (size <= helperThreshold)) |
344 | { |
345 | // If we have a buffer between XMM_REGSIZE_BYTES and CPBLK_UNROLL_LIMIT bytes, we'll use SSE2. |
346 | // Structs and buffer with sizes <= CPBLK_UNROLL_LIMIT bytes are occurring in more than 95% of |
347 | // our framework assemblies, so this is the main code generation scheme we'll use. |
348 | if (size <= CPBLK_UNROLL_LIMIT) |
349 | { |
350 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindUnroll; |
351 | |
352 | // If src or dst are on stack, we don't have to generate the address |
353 | // into a register because it's just some constant+SP. |
354 | if ((srcAddrOrFill != nullptr) && srcAddrOrFill->OperIsLocalAddr()) |
355 | { |
356 | MakeSrcContained(blkNode, srcAddrOrFill); |
357 | } |
358 | |
359 | if (dstAddr->OperIsLocalAddr()) |
360 | { |
361 | MakeSrcContained(blkNode, dstAddr); |
362 | } |
363 | } |
364 | else |
365 | { |
366 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindRepInstr; |
367 | } |
368 | } |
369 | #ifdef _TARGET_AMD64_ |
370 | else |
371 | { |
372 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindHelper; |
373 | } |
374 | #elif defined(_TARGET_X86_) |
375 | else |
376 | { |
377 | blkNode->gtBlkOpKind = GenTreeBlk::BlkOpKindRepInstr; |
378 | } |
379 | #endif // _TARGET_X86_ |
380 | assert(blkNode->gtBlkOpKind != GenTreeBlk::BlkOpKindInvalid); |
381 | } |
382 | |
383 | // CopyObj or CopyBlk |
384 | if (source->gtOper == GT_IND) |
385 | { |
386 | // The GT_IND is contained, but the address must be in a register unless it is local. |
387 | MakeSrcContained(blkNode, source); |
388 | GenTree* addr = source->AsIndir()->Addr(); |
389 | if (!addr->OperIsLocalAddr()) |
390 | { |
391 | addr->ClearContained(); |
392 | } |
393 | } |
394 | else if (!source->IsMultiRegCall() && !source->OperIsSIMD() && !source->OperIsSimdHWIntrinsic()) |
395 | { |
396 | assert(source->IsLocal()); |
397 | MakeSrcContained(blkNode, source); |
398 | } |
399 | } |
400 | } |
401 | |
402 | //------------------------------------------------------------------------ |
403 | // LowerPutArgStk: Lower a GT_PUTARG_STK. |
404 | // |
405 | // Arguments: |
406 | // tree - The node of interest |
407 | // |
408 | // Return Value: |
409 | // None. |
410 | // |
411 | void Lowering::LowerPutArgStk(GenTreePutArgStk* putArgStk) |
412 | { |
413 | #ifdef _TARGET_X86_ |
414 | if (putArgStk->gtOp1->gtOper == GT_FIELD_LIST) |
415 | { |
416 | putArgStk->gtNumberReferenceSlots = 0; |
417 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::Invalid; |
418 | |
419 | GenTreeFieldList* fieldList = putArgStk->gtOp1->AsFieldList(); |
420 | |
421 | // The code generator will push these fields in reverse order by offset. Reorder the list here s.t. the order |
422 | // of uses is visible to LSRA. |
423 | unsigned fieldCount = 0; |
424 | GenTreeFieldList* head = nullptr; |
425 | for (GenTreeFieldList *current = fieldList, *next; current != nullptr; current = next) |
426 | { |
427 | next = current->Rest(); |
428 | |
429 | // First, insert the field node into the sorted list. |
430 | GenTreeFieldList* prev = nullptr; |
431 | for (GenTreeFieldList* cursor = head;; cursor = cursor->Rest()) |
432 | { |
433 | // If the offset of the current list node is greater than the offset of the cursor or if we have |
434 | // reached the end of the list, insert the current node before the cursor and terminate. |
435 | if ((cursor == nullptr) || (current->gtFieldOffset > cursor->gtFieldOffset)) |
436 | { |
437 | if (prev == nullptr) |
438 | { |
439 | assert(cursor == head); |
440 | head = current; |
441 | } |
442 | else |
443 | { |
444 | prev->Rest() = current; |
445 | } |
446 | |
447 | current->Rest() = cursor; |
448 | break; |
449 | } |
450 | } |
451 | |
452 | fieldCount++; |
453 | } |
454 | |
455 | // In theory, the upper bound for the size of a field list is 8: these constructs only appear when passing the |
456 | // collection of lclVars that represent the fields of a promoted struct lclVar, and we do not promote struct |
457 | // lclVars with more than 4 fields. If each of these lclVars is of type long, decomposition will split the |
458 | // corresponding field list nodes in two, giving an upper bound of 8. |
459 | // |
460 | // The reason that this is important is that the algorithm we use above to sort the field list is O(N^2): if |
461 | // the maximum size of a field list grows significantly, we will need to reevaluate it. |
462 | assert(fieldCount <= 8); |
463 | |
464 | // The sort above may have changed which node is at the head of the list. Update the PUTARG_STK node if |
465 | // necessary. |
466 | if (head != fieldList) |
467 | { |
468 | head->gtFlags |= GTF_FIELD_LIST_HEAD; |
469 | head->SetContained(); |
470 | |
471 | fieldList->ClearContained(); |
472 | fieldList->gtFlags &= ~GTF_FIELD_LIST_HEAD; |
473 | |
474 | #ifdef DEBUG |
475 | head->gtSeqNum = fieldList->gtSeqNum; |
476 | #endif // DEBUG |
477 | |
478 | BlockRange().InsertAfter(fieldList, head); |
479 | BlockRange().Remove(fieldList); |
480 | |
481 | fieldList = head; |
482 | putArgStk->gtOp1 = fieldList; |
483 | putArgStk->gtType = fieldList->gtType; |
484 | } |
485 | |
486 | // Now that the fields have been sorted, the kind of code we will generate. |
487 | bool allFieldsAreSlots = true; |
488 | unsigned prevOffset = putArgStk->getArgSize(); |
489 | for (GenTreeFieldList* current = fieldList; current != nullptr; current = current->Rest()) |
490 | { |
491 | GenTree* const fieldNode = current->Current(); |
492 | const var_types fieldType = fieldNode->TypeGet(); |
493 | const unsigned fieldOffset = current->gtFieldOffset; |
494 | assert(fieldType != TYP_LONG); |
495 | |
496 | // We can treat as a slot any field that is stored at a slot boundary, where the previous |
497 | // field is not in the same slot. (Note that we store the fields in reverse order.) |
498 | const bool fieldIsSlot = ((fieldOffset % 4) == 0) && ((prevOffset - fieldOffset) >= 4); |
499 | if (!fieldIsSlot) |
500 | { |
501 | allFieldsAreSlots = false; |
502 | } |
503 | |
504 | if (varTypeIsGC(fieldType)) |
505 | { |
506 | putArgStk->gtNumberReferenceSlots++; |
507 | } |
508 | |
509 | // For x86 we must mark all integral fields as contained or reg-optional, and handle them |
510 | // accordingly in code generation, since we may have up to 8 fields, which cannot all be in |
511 | // registers to be consumed atomically by the call. |
512 | if (varTypeIsIntegralOrI(fieldNode)) |
513 | { |
514 | if (fieldNode->OperGet() == GT_LCL_VAR) |
515 | { |
516 | LclVarDsc* varDsc = &(comp->lvaTable[fieldNode->AsLclVarCommon()->gtLclNum]); |
517 | if (!varDsc->lvDoNotEnregister) |
518 | { |
519 | fieldNode->SetRegOptional(); |
520 | } |
521 | else |
522 | { |
523 | MakeSrcContained(putArgStk, fieldNode); |
524 | } |
525 | } |
526 | else if (fieldNode->IsIntCnsFitsInI32()) |
527 | { |
528 | MakeSrcContained(putArgStk, fieldNode); |
529 | } |
530 | else |
531 | { |
532 | // For the case where we cannot directly push the value, if we run out of registers, |
533 | // it would be better to defer computation until we are pushing the arguments rather |
534 | // than spilling, but this situation is not all that common, as most cases of promoted |
535 | // structs do not have a large number of fields, and of those most are lclVars or |
536 | // copy-propagated constants. |
537 | fieldNode->SetRegOptional(); |
538 | } |
539 | } |
540 | |
541 | prevOffset = fieldOffset; |
542 | } |
543 | |
544 | // Set the copy kind. |
545 | // TODO-X86-CQ: Even if we are using push, if there are contiguous floating point fields, we should |
546 | // adjust the stack once for those fields. The latter is really best done in code generation, but |
547 | // this tuning should probably be undertaken as a whole. |
548 | // Also, if there are floating point fields, it may be better to use the "Unroll" mode |
549 | // of copying the struct as a whole, if the fields are not register candidates. |
550 | if (allFieldsAreSlots) |
551 | { |
552 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::PushAllSlots; |
553 | } |
554 | else |
555 | { |
556 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::Push; |
557 | } |
558 | return; |
559 | } |
560 | #endif // _TARGET_X86_ |
561 | |
562 | GenTree* src = putArgStk->gtOp1; |
563 | |
564 | #ifdef FEATURE_PUT_STRUCT_ARG_STK |
565 | if (src->TypeGet() != TYP_STRUCT) |
566 | #endif // FEATURE_PUT_STRUCT_ARG_STK |
567 | { |
568 | // If the child of GT_PUTARG_STK is a constant, we don't need a register to |
569 | // move it to memory (stack location). |
570 | // |
571 | // On AMD64, we don't want to make 0 contained, because we can generate smaller code |
572 | // by zeroing a register and then storing it. E.g.: |
573 | // xor rdx, rdx |
574 | // mov gword ptr [rsp+28H], rdx |
575 | // is 2 bytes smaller than: |
576 | // mov gword ptr [rsp+28H], 0 |
577 | // |
578 | // On x86, we push stack arguments; we don't use 'mov'. So: |
579 | // push 0 |
580 | // is 1 byte smaller than: |
581 | // xor rdx, rdx |
582 | // push rdx |
583 | |
584 | if (IsContainableImmed(putArgStk, src) |
585 | #if defined(_TARGET_AMD64_) |
586 | && !src->IsIntegralConst(0) |
587 | #endif // _TARGET_AMD64_ |
588 | ) |
589 | { |
590 | MakeSrcContained(putArgStk, src); |
591 | } |
592 | return; |
593 | } |
594 | |
595 | #ifdef FEATURE_PUT_STRUCT_ARG_STK |
596 | GenTree* dst = putArgStk; |
597 | GenTree* srcAddr = nullptr; |
598 | |
599 | bool haveLocalAddr = false; |
600 | if ((src->OperGet() == GT_OBJ) || (src->OperGet() == GT_IND)) |
601 | { |
602 | srcAddr = src->gtOp.gtOp1; |
603 | assert(srcAddr != nullptr); |
604 | haveLocalAddr = srcAddr->OperIsLocalAddr(); |
605 | } |
606 | else |
607 | { |
608 | assert(varTypeIsSIMD(putArgStk)); |
609 | } |
610 | |
611 | // In case of a CpBlk we could use a helper call. In case of putarg_stk we |
612 | // can't do that since the helper call could kill some already set up outgoing args. |
613 | // TODO-Amd64-Unix: converge the code for putarg_stk with cpyblk/cpyobj. |
614 | // The cpyXXXX code is rather complex and this could cause it to be more complex, but |
615 | // it might be the right thing to do. |
616 | |
617 | // This threshold will decide from using the helper or let the JIT decide to inline |
618 | // a code sequence of its choice. |
619 | ssize_t helperThreshold = max(CPBLK_MOVS_LIMIT, CPBLK_UNROLL_LIMIT); |
620 | ssize_t size = putArgStk->gtNumSlots * TARGET_POINTER_SIZE; |
621 | |
622 | // TODO-X86-CQ: The helper call either is not supported on x86 or required more work |
623 | // (I don't know which). |
624 | |
625 | // If we have a buffer between XMM_REGSIZE_BYTES and CPBLK_UNROLL_LIMIT bytes, we'll use SSE2. |
626 | // Structs and buffer with sizes <= CPBLK_UNROLL_LIMIT bytes are occurring in more than 95% of |
627 | // our framework assemblies, so this is the main code generation scheme we'll use. |
628 | if (size <= CPBLK_UNROLL_LIMIT && putArgStk->gtNumberReferenceSlots == 0) |
629 | { |
630 | #ifdef _TARGET_X86_ |
631 | if (size < XMM_REGSIZE_BYTES) |
632 | { |
633 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::Push; |
634 | } |
635 | else |
636 | #endif // _TARGET_X86_ |
637 | { |
638 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::Unroll; |
639 | } |
640 | } |
641 | #ifdef _TARGET_X86_ |
642 | else if (putArgStk->gtNumberReferenceSlots != 0) |
643 | { |
644 | // On x86, we must use `push` to store GC references to the stack in order for the emitter to properly update |
645 | // the function's GC info. These `putargstk` nodes will generate a sequence of `push` instructions. |
646 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::Push; |
647 | } |
648 | #endif // _TARGET_X86_ |
649 | else |
650 | { |
651 | putArgStk->gtPutArgStkKind = GenTreePutArgStk::Kind::RepInstr; |
652 | } |
653 | // Always mark the OBJ and ADDR as contained trees by the putarg_stk. The codegen will deal with this tree. |
654 | MakeSrcContained(putArgStk, src); |
655 | if (haveLocalAddr) |
656 | { |
657 | // If the source address is the address of a lclVar, make the source address contained to avoid unnecessary |
658 | // copies. |
659 | // |
660 | MakeSrcContained(putArgStk, srcAddr); |
661 | } |
662 | #endif // FEATURE_PUT_STRUCT_ARG_STK |
663 | } |
664 | |
665 | /* Lower GT_CAST(srcType, DstType) nodes. |
666 | * |
667 | * Casts from small int type to float/double are transformed as follows: |
668 | * GT_CAST(byte, float/double) = GT_CAST(GT_CAST(byte, int32), float/double) |
669 | * GT_CAST(sbyte, float/double) = GT_CAST(GT_CAST(sbyte, int32), float/double) |
670 | * GT_CAST(int16, float/double) = GT_CAST(GT_CAST(int16, int32), float/double) |
671 | * GT_CAST(uint16, float/double) = GT_CAST(GT_CAST(uint16, int32), float/double) |
672 | * |
673 | * SSE2 conversion instructions operate on signed integers. casts from Uint32/Uint64 |
674 | * are morphed as follows by front-end and hence should not be seen here. |
675 | * GT_CAST(uint32, float/double) = GT_CAST(GT_CAST(uint32, long), float/double) |
676 | * GT_CAST(uint64, float) = GT_CAST(GT_CAST(uint64, double), float) |
677 | * |
678 | * |
679 | * Similarly casts from float/double to a smaller int type are transformed as follows: |
680 | * GT_CAST(float/double, byte) = GT_CAST(GT_CAST(float/double, int32), byte) |
681 | * GT_CAST(float/double, sbyte) = GT_CAST(GT_CAST(float/double, int32), sbyte) |
682 | * GT_CAST(float/double, int16) = GT_CAST(GT_CAST(double/double, int32), int16) |
683 | * GT_CAST(float/double, uint16) = GT_CAST(GT_CAST(double/double, int32), uint16) |
684 | * |
685 | * SSE2 has instructions to convert a float/double vlaue into a signed 32/64-bit |
686 | * integer. The above transformations help us to leverage those instructions. |
687 | * |
688 | * Note that for the following conversions we still depend on helper calls and |
689 | * don't expect to see them here. |
690 | * i) GT_CAST(float/double, uint64) |
691 | * ii) GT_CAST(float/double, int type with overflow detection) |
692 | * |
693 | * TODO-XArch-CQ: (Low-pri): Jit64 generates in-line code of 8 instructions for (i) above. |
694 | * There are hardly any occurrences of this conversion operation in platform |
695 | * assemblies or in CQ perf benchmarks (1 occurrence in mscorlib, microsoft.jscript, |
696 | * 1 occurence in Roslyn and no occurrences in system, system.core, system.numerics |
697 | * system.windows.forms, scimark, fractals, bio mums). If we ever find evidence that |
698 | * doing this optimization is a win, should consider generating in-lined code. |
699 | */ |
700 | void Lowering::LowerCast(GenTree* tree) |
701 | { |
702 | assert(tree->OperGet() == GT_CAST); |
703 | |
704 | GenTree* castOp = tree->gtCast.CastOp(); |
705 | var_types castToType = tree->CastToType(); |
706 | var_types srcType = castOp->TypeGet(); |
707 | var_types tmpType = TYP_UNDEF; |
708 | |
709 | // force the srcType to unsigned if GT_UNSIGNED flag is set |
710 | if (tree->gtFlags & GTF_UNSIGNED) |
711 | { |
712 | srcType = genUnsignedType(srcType); |
713 | } |
714 | |
715 | // We should never see the following casts as they are expected to be lowered |
716 | // apropriately or converted into helper calls by front-end. |
717 | // srcType = float/double castToType = * and overflow detecting cast |
718 | // Reason: must be converted to a helper call |
719 | // srcType = float/double, castToType = ulong |
720 | // Reason: must be converted to a helper call |
721 | // srcType = uint castToType = float/double |
722 | // Reason: uint -> float/double = uint -> long -> float/double |
723 | // srcType = ulong castToType = float |
724 | // Reason: ulong -> float = ulong -> double -> float |
725 | if (varTypeIsFloating(srcType)) |
726 | { |
727 | noway_assert(!tree->gtOverflow()); |
728 | noway_assert(castToType != TYP_ULONG); |
729 | } |
730 | else if (srcType == TYP_UINT) |
731 | { |
732 | noway_assert(!varTypeIsFloating(castToType)); |
733 | } |
734 | else if (srcType == TYP_ULONG) |
735 | { |
736 | noway_assert(castToType != TYP_FLOAT); |
737 | } |
738 | |
739 | // Case of src is a small type and dst is a floating point type. |
740 | if (varTypeIsSmall(srcType) && varTypeIsFloating(castToType)) |
741 | { |
742 | // These conversions can never be overflow detecting ones. |
743 | noway_assert(!tree->gtOverflow()); |
744 | tmpType = TYP_INT; |
745 | } |
746 | // case of src is a floating point type and dst is a small type. |
747 | else if (varTypeIsFloating(srcType) && varTypeIsSmall(castToType)) |
748 | { |
749 | tmpType = TYP_INT; |
750 | } |
751 | |
752 | if (tmpType != TYP_UNDEF) |
753 | { |
754 | GenTree* tmp = comp->gtNewCastNode(tmpType, castOp, tree->IsUnsigned(), tmpType); |
755 | tmp->gtFlags |= (tree->gtFlags & (GTF_OVERFLOW | GTF_EXCEPT)); |
756 | |
757 | tree->gtFlags &= ~GTF_UNSIGNED; |
758 | tree->gtOp.gtOp1 = tmp; |
759 | BlockRange().InsertAfter(castOp, tmp); |
760 | ContainCheckCast(tmp->AsCast()); |
761 | } |
762 | |
763 | // Now determine if we have operands that should be contained. |
764 | ContainCheckCast(tree->AsCast()); |
765 | } |
766 | |
767 | #ifdef FEATURE_SIMD |
768 | //---------------------------------------------------------------------------------------------- |
769 | // Lowering::LowerSIMD: Perform containment analysis for a SIMD intrinsic node. |
770 | // |
771 | // Arguments: |
772 | // simdNode - The SIMD intrinsic node. |
773 | // |
774 | void Lowering::LowerSIMD(GenTreeSIMD* simdNode) |
775 | { |
776 | if (simdNode->TypeGet() == TYP_SIMD12) |
777 | { |
778 | // GT_SIMD node requiring to produce TYP_SIMD12 in fact |
779 | // produces a TYP_SIMD16 result |
780 | simdNode->gtType = TYP_SIMD16; |
781 | } |
782 | |
783 | #ifdef _TARGET_XARCH_ |
784 | if ((simdNode->gtSIMDIntrinsicID == SIMDIntrinsicGetItem) && (simdNode->gtGetOp1()->OperGet() == GT_IND)) |
785 | { |
786 | // If SIMD vector is already in memory, we force its |
787 | // addr to be evaluated into a reg. This would allow |
788 | // us to generate [regBase] or [regBase+offset] or |
789 | // [regBase+sizeOf(SIMD vector baseType)*regIndex] |
790 | // to access the required SIMD vector element directly |
791 | // from memory. |
792 | // |
793 | // TODO-CQ-XARCH: If addr of GT_IND is GT_LEA, we |
794 | // might be able update GT_LEA to fold the regIndex |
795 | // or offset in some cases. Instead with this |
796 | // approach we always evaluate GT_LEA into a reg. |
797 | // Ideally, we should be able to lower GetItem intrinsic |
798 | // into GT_IND(newAddr) where newAddr combines |
799 | // the addr of SIMD vector with the given index. |
800 | simdNode->gtOp1->gtFlags |= GTF_IND_REQ_ADDR_IN_REG; |
801 | } |
802 | else if (simdNode->IsSIMDEqualityOrInequality()) |
803 | { |
804 | LIR::Use simdUse; |
805 | |
806 | if (BlockRange().TryGetUse(simdNode, &simdUse)) |
807 | { |
808 | // |
809 | // Try to transform JTRUE(EQ|NE(SIMD<OpEquality|OpInEquality>(x, y), 0|1)) into |
810 | // JCC(SIMD<OpEquality|OpInEquality>(x, y)). SIMD<OpEquality|OpInEquality>(x, y) |
811 | // is expected to set the Zero flag appropriately. |
812 | // All the involved nodes must form a continuous range, there's no other way to |
813 | // guarantee that condition flags aren't changed between the SIMD node and the JCC |
814 | // node. |
815 | // |
816 | |
817 | bool transformed = false; |
818 | GenTree* simdUser = simdUse.User(); |
819 | |
820 | if (simdUser->OperIs(GT_EQ, GT_NE) && simdUser->gtGetOp2()->IsCnsIntOrI() && |
821 | (simdNode->gtNext == simdUser->gtGetOp2()) && (simdUser->gtGetOp2()->gtNext == simdUser)) |
822 | { |
823 | ssize_t relopOp2Value = simdUser->gtGetOp2()->AsIntCon()->IconValue(); |
824 | |
825 | if ((relopOp2Value == 0) || (relopOp2Value == 1)) |
826 | { |
827 | GenTree* jtrue = simdUser->gtNext; |
828 | |
829 | if ((jtrue != nullptr) && jtrue->OperIs(GT_JTRUE) && (jtrue->gtGetOp1() == simdUser)) |
830 | { |
831 | if ((simdNode->gtSIMDIntrinsicID == SIMDIntrinsicOpEquality) != simdUser->OperIs(GT_EQ)) |
832 | { |
833 | relopOp2Value ^= 1; |
834 | } |
835 | |
836 | jtrue->ChangeOper(GT_JCC); |
837 | GenTreeCC* jcc = jtrue->AsCC(); |
838 | jcc->gtFlags |= GTF_USE_FLAGS; |
839 | jcc->gtCondition = (relopOp2Value == 0) ? GT_NE : GT_EQ; |
840 | |
841 | BlockRange().Remove(simdUser->gtGetOp2()); |
842 | BlockRange().Remove(simdUser); |
843 | transformed = true; |
844 | } |
845 | } |
846 | } |
847 | |
848 | if (!transformed) |
849 | { |
850 | // |
851 | // The code generated for SIMD SIMD<OpEquality|OpInEquality>(x, y) nodes sets |
852 | // the Zero flag like integer compares do so we can simply use SETCC<EQ|NE> |
853 | // to produce the desired result. This avoids the need for subsequent phases |
854 | // to have to handle 2 cases (set flags/set destination register). |
855 | // |
856 | |
857 | genTreeOps condition = (simdNode->gtSIMDIntrinsicID == SIMDIntrinsicOpEquality) ? GT_EQ : GT_NE; |
858 | GenTreeCC* setcc = new (comp, GT_SETCC) GenTreeCC(GT_SETCC, condition, simdNode->TypeGet()); |
859 | setcc->gtFlags |= GTF_USE_FLAGS; |
860 | BlockRange().InsertAfter(simdNode, setcc); |
861 | simdUse.ReplaceWith(comp, setcc); |
862 | } |
863 | } |
864 | |
865 | simdNode->gtFlags |= GTF_SET_FLAGS; |
866 | simdNode->gtType = TYP_VOID; |
867 | } |
868 | #endif |
869 | ContainCheckSIMD(simdNode); |
870 | } |
871 | #endif // FEATURE_SIMD |
872 | |
873 | #ifdef FEATURE_HW_INTRINSICS |
874 | //---------------------------------------------------------------------------------------------- |
875 | // Lowering::LowerHWIntrinsic: Perform containment analysis for a hardware intrinsic node. |
876 | // |
877 | // Arguments: |
878 | // node - The hardware intrinsic node. |
879 | // |
880 | void Lowering::LowerHWIntrinsic(GenTreeHWIntrinsic* node) |
881 | { |
882 | ContainCheckHWIntrinsic(node); |
883 | } |
884 | #endif // FEATURE_HW_INTRINSICS |
885 | |
886 | //---------------------------------------------------------------------------------------------- |
887 | // Lowering::IsRMWIndirCandidate: |
888 | // Returns true if the given operand is a candidate indirection for a read-modify-write |
889 | // operator. |
890 | // |
891 | // Arguments: |
892 | // operand - The operand to consider. |
893 | // storeInd - The indirect store that roots the possible RMW operator. |
894 | // |
895 | bool Lowering::IsRMWIndirCandidate(GenTree* operand, GenTree* storeInd) |
896 | { |
897 | // If the operand isn't an indirection, it's trivially not a candidate. |
898 | if (operand->OperGet() != GT_IND) |
899 | { |
900 | return false; |
901 | } |
902 | |
903 | // If the indirection's source address isn't equivalent to the destination address of the storeIndir, then the |
904 | // indirection is not a candidate. |
905 | GenTree* srcAddr = operand->gtGetOp1(); |
906 | GenTree* dstAddr = storeInd->gtGetOp1(); |
907 | if ((srcAddr->OperGet() != dstAddr->OperGet()) || !IndirsAreEquivalent(operand, storeInd)) |
908 | { |
909 | return false; |
910 | } |
911 | |
912 | // If it is not safe to contain the entire tree rooted at the indirection, then the indirection is not a |
913 | // candidate. Crawl the IR from the node immediately preceding the storeIndir until the last node in the |
914 | // indirection's tree is visited and check the side effects at each point. |
915 | |
916 | m_scratchSideEffects.Clear(); |
917 | |
918 | assert((operand->gtLIRFlags & LIR::Flags::Mark) == 0); |
919 | operand->gtLIRFlags |= LIR::Flags::Mark; |
920 | |
921 | unsigned markCount = 1; |
922 | GenTree* node; |
923 | for (node = storeInd->gtPrev; markCount > 0; node = node->gtPrev) |
924 | { |
925 | assert(node != nullptr); |
926 | |
927 | if ((node->gtLIRFlags & LIR::Flags::Mark) == 0) |
928 | { |
929 | m_scratchSideEffects.AddNode(comp, node); |
930 | } |
931 | else |
932 | { |
933 | node->gtLIRFlags &= ~LIR::Flags::Mark; |
934 | markCount--; |
935 | |
936 | if (m_scratchSideEffects.InterferesWith(comp, node, false)) |
937 | { |
938 | // The indirection's tree contains some node that can't be moved to the storeInder. The indirection is |
939 | // not a candidate. Clear any leftover mark bits and return. |
940 | for (; markCount > 0; node = node->gtPrev) |
941 | { |
942 | if ((node->gtLIRFlags & LIR::Flags::Mark) != 0) |
943 | { |
944 | node->gtLIRFlags &= ~LIR::Flags::Mark; |
945 | markCount--; |
946 | } |
947 | } |
948 | return false; |
949 | } |
950 | |
951 | node->VisitOperands([&markCount](GenTree* nodeOperand) -> GenTree::VisitResult { |
952 | assert((nodeOperand->gtLIRFlags & LIR::Flags::Mark) == 0); |
953 | nodeOperand->gtLIRFlags |= LIR::Flags::Mark; |
954 | markCount++; |
955 | return GenTree::VisitResult::Continue; |
956 | }); |
957 | } |
958 | } |
959 | |
960 | // At this point we've verified that the operand is an indirection, its address is equivalent to the storeIndir's |
961 | // destination address, and that it and the transitive closure of its operand can be safely contained by the |
962 | // storeIndir. This indirection is therefore a candidate for an RMW op. |
963 | return true; |
964 | } |
965 | |
966 | //---------------------------------------------------------------------------------------------- |
967 | // Returns true if this tree is bin-op of a GT_STOREIND of the following form |
968 | // storeInd(subTreeA, binOp(gtInd(subTreeA), subtreeB)) or |
969 | // storeInd(subTreeA, binOp(subtreeB, gtInd(subTreeA)) in case of commutative bin-ops |
970 | // |
971 | // The above form for storeInd represents a read-modify-write memory binary operation. |
972 | // |
973 | // Parameters |
974 | // tree - GentreePtr of binOp |
975 | // |
976 | // Return Value |
977 | // True if 'tree' is part of a RMW memory operation pattern |
978 | // |
979 | bool Lowering::IsBinOpInRMWStoreInd(GenTree* tree) |
980 | { |
981 | // Must be a non floating-point type binary operator since SSE2 doesn't support RMW memory ops |
982 | assert(!varTypeIsFloating(tree)); |
983 | assert(GenTree::OperIsBinary(tree->OperGet())); |
984 | |
985 | // Cheap bail out check before more expensive checks are performed. |
986 | // RMW memory op pattern requires that one of the operands of binOp to be GT_IND. |
987 | if (tree->gtGetOp1()->OperGet() != GT_IND && tree->gtGetOp2()->OperGet() != GT_IND) |
988 | { |
989 | return false; |
990 | } |
991 | |
992 | LIR::Use use; |
993 | if (!BlockRange().TryGetUse(tree, &use) || use.User()->OperGet() != GT_STOREIND || use.User()->gtGetOp2() != tree) |
994 | { |
995 | return false; |
996 | } |
997 | |
998 | // Since it is not relatively cheap to recognize RMW memory op pattern, we |
999 | // cache the result in GT_STOREIND node so that while lowering GT_STOREIND |
1000 | // we can use the result. |
1001 | GenTree* indirCandidate = nullptr; |
1002 | GenTree* indirOpSource = nullptr; |
1003 | return IsRMWMemOpRootedAtStoreInd(use.User(), &indirCandidate, &indirOpSource); |
1004 | } |
1005 | |
1006 | //---------------------------------------------------------------------------------------------- |
1007 | // This method recognizes the case where we have a treeNode with the following structure: |
1008 | // storeInd(IndirDst, binOp(gtInd(IndirDst), indirOpSource)) OR |
1009 | // storeInd(IndirDst, binOp(indirOpSource, gtInd(IndirDst)) in case of commutative operations OR |
1010 | // storeInd(IndirDst, unaryOp(gtInd(IndirDst)) in case of unary operations |
1011 | // |
1012 | // Terminology: |
1013 | // indirDst = memory write of an addr mode (i.e. storeind destination) |
1014 | // indirSrc = value being written to memory (i.e. storeind source which could either be a binary or unary op) |
1015 | // indirCandidate = memory read i.e. a gtInd of an addr mode |
1016 | // indirOpSource = source operand used in binary/unary op (i.e. source operand of indirSrc node) |
1017 | // |
1018 | // In x86/x64 this storeInd pattern can be effectively encoded in a single instruction of the |
1019 | // following form in case of integer operations: |
1020 | // binOp [addressing mode], RegIndirOpSource |
1021 | // binOp [addressing mode], immediateVal |
1022 | // where RegIndirOpSource is the register where indirOpSource was computed. |
1023 | // |
1024 | // Right now, we recognize few cases: |
1025 | // a) The gtInd child is a lea/lclVar/lclVarAddr/clsVarAddr/constant |
1026 | // b) BinOp is either add, sub, xor, or, and, shl, rsh, rsz. |
1027 | // c) unaryOp is either not/neg |
1028 | // |
1029 | // Implementation Note: The following routines need to be in sync for RMW memory op optimization |
1030 | // to be correct and functional. |
1031 | // IndirsAreEquivalent() |
1032 | // NodesAreEquivalentLeaves() |
1033 | // Codegen of GT_STOREIND and genCodeForShiftRMW() |
1034 | // emitInsRMW() |
1035 | // |
1036 | // TODO-CQ: Enable support for more complex indirections (if needed) or use the value numbering |
1037 | // package to perform more complex tree recognition. |
1038 | // |
1039 | // TODO-XArch-CQ: Add support for RMW of lcl fields (e.g. lclfield binop= source) |
1040 | // |
1041 | // Parameters: |
1042 | // tree - GT_STOREIND node |
1043 | // outIndirCandidate - out param set to indirCandidate as described above |
1044 | // ouutIndirOpSource - out param set to indirOpSource as described above |
1045 | // |
1046 | // Return value |
1047 | // True if there is a RMW memory operation rooted at a GT_STOREIND tree |
1048 | // and out params indirCandidate and indirOpSource are set to non-null values. |
1049 | // Otherwise, returns false with indirCandidate and indirOpSource set to null. |
1050 | // Also updates flags of GT_STOREIND tree with its RMW status. |
1051 | // |
1052 | bool Lowering::IsRMWMemOpRootedAtStoreInd(GenTree* tree, GenTree** outIndirCandidate, GenTree** outIndirOpSource) |
1053 | { |
1054 | assert(!varTypeIsFloating(tree)); |
1055 | assert(outIndirCandidate != nullptr); |
1056 | assert(outIndirOpSource != nullptr); |
1057 | |
1058 | *outIndirCandidate = nullptr; |
1059 | *outIndirOpSource = nullptr; |
1060 | |
1061 | // Early out if storeInd is already known to be a non-RMW memory op |
1062 | GenTreeStoreInd* storeInd = tree->AsStoreInd(); |
1063 | if (storeInd->IsNonRMWMemoryOp()) |
1064 | { |
1065 | return false; |
1066 | } |
1067 | |
1068 | GenTree* indirDst = storeInd->gtGetOp1(); |
1069 | GenTree* indirSrc = storeInd->gtGetOp2(); |
1070 | genTreeOps oper = indirSrc->OperGet(); |
1071 | |
1072 | // Early out if it is already known to be a RMW memory op |
1073 | if (storeInd->IsRMWMemoryOp()) |
1074 | { |
1075 | if (GenTree::OperIsBinary(oper)) |
1076 | { |
1077 | if (storeInd->IsRMWDstOp1()) |
1078 | { |
1079 | *outIndirCandidate = indirSrc->gtGetOp1(); |
1080 | *outIndirOpSource = indirSrc->gtGetOp2(); |
1081 | } |
1082 | else |
1083 | { |
1084 | assert(storeInd->IsRMWDstOp2()); |
1085 | *outIndirCandidate = indirSrc->gtGetOp2(); |
1086 | *outIndirOpSource = indirSrc->gtGetOp1(); |
1087 | } |
1088 | assert(IndirsAreEquivalent(*outIndirCandidate, storeInd)); |
1089 | } |
1090 | else |
1091 | { |
1092 | assert(GenTree::OperIsUnary(oper)); |
1093 | assert(IndirsAreEquivalent(indirSrc->gtGetOp1(), storeInd)); |
1094 | *outIndirCandidate = indirSrc->gtGetOp1(); |
1095 | *outIndirOpSource = indirSrc->gtGetOp1(); |
1096 | } |
1097 | |
1098 | return true; |
1099 | } |
1100 | |
1101 | // If reached here means that we do not know RMW status of tree rooted at storeInd |
1102 | assert(storeInd->IsRMWStatusUnknown()); |
1103 | |
1104 | // Early out if indirDst is not one of the supported memory operands. |
1105 | if (indirDst->OperGet() != GT_LEA && indirDst->OperGet() != GT_LCL_VAR && indirDst->OperGet() != GT_LCL_VAR_ADDR && |
1106 | indirDst->OperGet() != GT_CLS_VAR_ADDR && indirDst->OperGet() != GT_CNS_INT) |
1107 | { |
1108 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_ADDR); |
1109 | return false; |
1110 | } |
1111 | |
1112 | // We can not use Read-Modify-Write instruction forms with overflow checking instructions |
1113 | // because we are not allowed to modify the target until after the overflow check. |
1114 | if (indirSrc->gtOverflowEx()) |
1115 | { |
1116 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_OPER); |
1117 | return false; |
1118 | } |
1119 | |
1120 | // At this point we can match one of two patterns: |
1121 | // |
1122 | // t_ind = indir t_addr_0 |
1123 | // ... |
1124 | // t_value = binop t_ind, t_other |
1125 | // ... |
1126 | // storeIndir t_addr_1, t_value |
1127 | // |
1128 | // or |
1129 | // |
1130 | // t_ind = indir t_addr_0 |
1131 | // ... |
1132 | // t_value = unop t_ind |
1133 | // ... |
1134 | // storeIndir t_addr_1, t_value |
1135 | // |
1136 | // In all cases, we will eventually make the binop that produces t_value and the entire dataflow tree rooted at |
1137 | // t_ind contained by t_value. |
1138 | |
1139 | GenTree* indirCandidate = nullptr; |
1140 | GenTree* indirOpSource = nullptr; |
1141 | RMWStatus status = STOREIND_RMW_STATUS_UNKNOWN; |
1142 | if (GenTree::OperIsBinary(oper)) |
1143 | { |
1144 | // Return if binary op is not one of the supported operations for RMW of memory. |
1145 | if (!GenTree::OperIsRMWMemOp(oper)) |
1146 | { |
1147 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_OPER); |
1148 | return false; |
1149 | } |
1150 | |
1151 | if (GenTree::OperIsShiftOrRotate(oper) && varTypeIsSmall(storeInd)) |
1152 | { |
1153 | // In ldind, Integer values smaller than 4 bytes, a boolean, or a character converted to 4 bytes |
1154 | // by sign or zero-extension as appropriate. If we directly shift the short type data using sar, we |
1155 | // will lose the sign or zero-extension bits. |
1156 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_TYPE); |
1157 | return false; |
1158 | } |
1159 | |
1160 | // In the common case, the second operand to the binop will be the indir candidate. |
1161 | GenTreeOp* binOp = indirSrc->AsOp(); |
1162 | if (GenTree::OperIsCommutative(oper) && IsRMWIndirCandidate(binOp->gtOp2, storeInd)) |
1163 | { |
1164 | indirCandidate = binOp->gtOp2; |
1165 | indirOpSource = binOp->gtOp1; |
1166 | status = STOREIND_RMW_DST_IS_OP2; |
1167 | } |
1168 | else if (IsRMWIndirCandidate(binOp->gtOp1, storeInd)) |
1169 | { |
1170 | indirCandidate = binOp->gtOp1; |
1171 | indirOpSource = binOp->gtOp2; |
1172 | status = STOREIND_RMW_DST_IS_OP1; |
1173 | } |
1174 | else |
1175 | { |
1176 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_ADDR); |
1177 | return false; |
1178 | } |
1179 | } |
1180 | else if (GenTree::OperIsUnary(oper)) |
1181 | { |
1182 | // Nodes other than GT_NOT and GT_NEG are not yet supported. |
1183 | if (oper != GT_NOT && oper != GT_NEG) |
1184 | { |
1185 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_OPER); |
1186 | return false; |
1187 | } |
1188 | |
1189 | if (indirSrc->gtGetOp1()->OperGet() != GT_IND) |
1190 | { |
1191 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_ADDR); |
1192 | return false; |
1193 | } |
1194 | |
1195 | GenTreeUnOp* unOp = indirSrc->AsUnOp(); |
1196 | if (IsRMWIndirCandidate(unOp->gtOp1, storeInd)) |
1197 | { |
1198 | // src and dest are the same in case of unary ops |
1199 | indirCandidate = unOp->gtOp1; |
1200 | indirOpSource = unOp->gtOp1; |
1201 | status = STOREIND_RMW_DST_IS_OP1; |
1202 | } |
1203 | else |
1204 | { |
1205 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_ADDR); |
1206 | return false; |
1207 | } |
1208 | } |
1209 | else |
1210 | { |
1211 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_OPER); |
1212 | return false; |
1213 | } |
1214 | |
1215 | // By this point we've verified that we have a supported operand with a supported address. Now we need to ensure |
1216 | // that we're able to move the destination address for the source indirection forwards. |
1217 | if (!IsSafeToContainMem(storeInd, indirDst)) |
1218 | { |
1219 | storeInd->SetRMWStatus(STOREIND_RMW_UNSUPPORTED_ADDR); |
1220 | return false; |
1221 | } |
1222 | |
1223 | assert(indirCandidate != nullptr); |
1224 | assert(indirOpSource != nullptr); |
1225 | assert(status != STOREIND_RMW_STATUS_UNKNOWN); |
1226 | |
1227 | *outIndirCandidate = indirCandidate; |
1228 | *outIndirOpSource = indirOpSource; |
1229 | storeInd->SetRMWStatus(status); |
1230 | return true; |
1231 | } |
1232 | |
1233 | // anything is in range for AMD64 |
1234 | bool Lowering::IsCallTargetInRange(void* addr) |
1235 | { |
1236 | return true; |
1237 | } |
1238 | |
1239 | // return true if the immediate can be folded into an instruction, for example small enough and non-relocatable |
1240 | bool Lowering::IsContainableImmed(GenTree* parentNode, GenTree* childNode) |
1241 | { |
1242 | if (!childNode->IsIntCnsFitsInI32()) |
1243 | { |
1244 | return false; |
1245 | } |
1246 | |
1247 | // At this point we know that it is an int const fits within 4-bytes and hence can safely cast to IntConCommon. |
1248 | // Icons that need relocation should never be marked as contained immed |
1249 | if (childNode->AsIntConCommon()->ImmedValNeedsReloc(comp)) |
1250 | { |
1251 | return false; |
1252 | } |
1253 | |
1254 | return true; |
1255 | } |
1256 | |
1257 | //----------------------------------------------------------------------- |
1258 | // PreferredRegOptionalOperand: returns one of the operands of given |
1259 | // binary oper that is to be preferred for marking as reg optional. |
1260 | // |
1261 | // Since only one of op1 or op2 can be a memory operand on xarch, only |
1262 | // one of them have to be marked as reg optional. Since Lower doesn't |
1263 | // know apriori which of op1 or op2 is not likely to get a register, it |
1264 | // has to make a guess. This routine encapsulates heuristics that |
1265 | // guess whether it is likely to be beneficial to mark op1 or op2 as |
1266 | // reg optional. |
1267 | // |
1268 | // |
1269 | // Arguments: |
1270 | // tree - a binary-op tree node that is either commutative |
1271 | // or a compare oper. |
1272 | // |
1273 | // Returns: |
1274 | // Returns op1 or op2 of tree node that is preferred for |
1275 | // marking as reg optional. |
1276 | // |
1277 | // Note: if the tree oper is neither commutative nor a compare oper |
1278 | // then only op2 can be reg optional on xarch and hence no need to |
1279 | // call this routine. |
1280 | GenTree* Lowering::PreferredRegOptionalOperand(GenTree* tree) |
1281 | { |
1282 | assert(GenTree::OperIsBinary(tree->OperGet())); |
1283 | assert(tree->OperIsCommutative() || tree->OperIsCompare() || tree->OperIs(GT_CMP)); |
1284 | |
1285 | GenTree* op1 = tree->gtGetOp1(); |
1286 | GenTree* op2 = tree->gtGetOp2(); |
1287 | assert(!op1->IsRegOptional() && !op2->IsRegOptional()); |
1288 | |
1289 | // We default to op1, as op2 is likely to have the shorter lifetime. |
1290 | GenTree* preferredOp = op1; |
1291 | |
1292 | // This routine uses the following heuristics: |
1293 | // |
1294 | // a) If both are register candidates, marking the one with lower weighted |
1295 | // ref count as reg-optional would likely be beneficial as it has |
1296 | // higher probability of not getting a register. Note that we use !lvDoNotEnregister |
1297 | // here because this is being done while we are adding lclVars for Lowering. |
1298 | // |
1299 | // b) op1 = tracked local and op2 = untracked local: LSRA creates two |
1300 | // ref positions for op2: a def and use position. op2's def position |
1301 | // requires a reg and it is allocated a reg by spilling another |
1302 | // interval (if required) and that could be even op1. For this reason |
1303 | // it is beneficial to mark op1 as reg optional. |
1304 | // |
1305 | // TODO: It is not always mandatory for a def position of an untracked |
1306 | // local to be allocated a register if it is on rhs of an assignment |
1307 | // and its use position is reg-optional and has not been assigned a |
1308 | // register. Reg optional def positions is currently not yet supported. |
1309 | // |
1310 | // c) op1 = untracked local and op2 = tracked local: marking op1 as |
1311 | // reg optional is beneficial, since its use position is less likely |
1312 | // to get a register. |
1313 | // |
1314 | // d) If both are untracked locals (i.e. treated like tree temps by |
1315 | // LSRA): though either of them could be marked as reg optional, |
1316 | // marking op1 as reg optional is likely to be beneficial because |
1317 | // while allocating op2's def position, there is a possibility of |
1318 | // spilling op1's def and in which case op1 is treated as contained |
1319 | // memory operand rather than requiring to reload. |
1320 | // |
1321 | // e) If only one of them is a local var, prefer to mark it as |
1322 | // reg-optional. This is heuristic is based on the results |
1323 | // obtained against CQ perf benchmarks. |
1324 | // |
1325 | // f) If neither of them are local vars (i.e. tree temps), prefer to |
1326 | // mark op1 as reg optional for the same reason as mentioned in (d) above. |
1327 | if (op1->OperGet() == GT_LCL_VAR && op2->OperGet() == GT_LCL_VAR) |
1328 | { |
1329 | LclVarDsc* v1 = comp->lvaTable + op1->AsLclVarCommon()->GetLclNum(); |
1330 | LclVarDsc* v2 = comp->lvaTable + op2->AsLclVarCommon()->GetLclNum(); |
1331 | |
1332 | bool v1IsRegCandidate = !v1->lvDoNotEnregister; |
1333 | bool v2IsRegCandidate = !v2->lvDoNotEnregister; |
1334 | if (v1IsRegCandidate && v2IsRegCandidate) |
1335 | { |
1336 | // Both are enregisterable locals. The one with lower weight is less likely |
1337 | // to get a register and hence beneficial to mark the one with lower |
1338 | // weight as reg optional. |
1339 | // If either is not tracked, it may be that it was introduced after liveness |
1340 | // was run, in which case we will always prefer op1 (should we use raw refcnt??). |
1341 | if (v1->lvTracked && v2->lvTracked && (v1->lvRefCntWtd() >= v2->lvRefCntWtd())) |
1342 | { |
1343 | preferredOp = op2; |
1344 | } |
1345 | } |
1346 | } |
1347 | else if (!(op1->OperGet() == GT_LCL_VAR) && (op2->OperGet() == GT_LCL_VAR)) |
1348 | { |
1349 | preferredOp = op2; |
1350 | } |
1351 | |
1352 | return preferredOp; |
1353 | } |
1354 | |
1355 | //------------------------------------------------------------------------ |
1356 | // Containment analysis |
1357 | //------------------------------------------------------------------------ |
1358 | |
1359 | //------------------------------------------------------------------------ |
1360 | // ContainCheckCallOperands: Determine whether operands of a call should be contained. |
1361 | // |
1362 | // Arguments: |
1363 | // call - The call node of interest |
1364 | // |
1365 | // Return Value: |
1366 | // None. |
1367 | // |
1368 | void Lowering::ContainCheckCallOperands(GenTreeCall* call) |
1369 | { |
1370 | GenTree* ctrlExpr = call->gtControlExpr; |
1371 | if (call->gtCallType == CT_INDIRECT) |
1372 | { |
1373 | // either gtControlExpr != null or gtCallAddr != null. |
1374 | // Both cannot be non-null at the same time. |
1375 | assert(ctrlExpr == nullptr); |
1376 | assert(call->gtCallAddr != nullptr); |
1377 | ctrlExpr = call->gtCallAddr; |
1378 | |
1379 | #ifdef _TARGET_X86_ |
1380 | // Fast tail calls aren't currently supported on x86, but if they ever are, the code |
1381 | // below that handles indirect VSD calls will need to be fixed. |
1382 | assert(!call->IsFastTailCall() || !call->IsVirtualStub()); |
1383 | #endif // _TARGET_X86_ |
1384 | } |
1385 | |
1386 | // set reg requirements on call target represented as control sequence. |
1387 | if (ctrlExpr != nullptr) |
1388 | { |
1389 | // we should never see a gtControlExpr whose type is void. |
1390 | assert(ctrlExpr->TypeGet() != TYP_VOID); |
1391 | |
1392 | // In case of fast tail implemented as jmp, make sure that gtControlExpr is |
1393 | // computed into a register. |
1394 | if (!call->IsFastTailCall()) |
1395 | { |
1396 | #ifdef _TARGET_X86_ |
1397 | // On x86, we need to generate a very specific pattern for indirect VSD calls: |
1398 | // |
1399 | // 3-byte nop |
1400 | // call dword ptr [eax] |
1401 | // |
1402 | // Where EAX is also used as an argument to the stub dispatch helper. Make |
1403 | // sure that the call target address is computed into EAX in this case. |
1404 | if (call->IsVirtualStub() && (call->gtCallType == CT_INDIRECT)) |
1405 | { |
1406 | assert(ctrlExpr->isIndir()); |
1407 | MakeSrcContained(call, ctrlExpr); |
1408 | } |
1409 | else |
1410 | #endif // _TARGET_X86_ |
1411 | if (ctrlExpr->isIndir()) |
1412 | { |
1413 | // We may have cases where we have set a register target on the ctrlExpr, but if it |
1414 | // contained we must clear it. |
1415 | ctrlExpr->gtRegNum = REG_NA; |
1416 | MakeSrcContained(call, ctrlExpr); |
1417 | } |
1418 | } |
1419 | } |
1420 | |
1421 | GenTree* args = call->gtCallArgs; |
1422 | while (args) |
1423 | { |
1424 | GenTree* arg = args->gtOp.gtOp1; |
1425 | if (arg->gtOper == GT_PUTARG_STK) |
1426 | { |
1427 | LowerPutArgStk(arg->AsPutArgStk()); |
1428 | } |
1429 | args = args->gtOp.gtOp2; |
1430 | } |
1431 | args = call->gtCallLateArgs; |
1432 | while (args) |
1433 | { |
1434 | GenTree* arg = args->gtOp.gtOp1; |
1435 | if (arg->gtOper == GT_PUTARG_STK) |
1436 | { |
1437 | LowerPutArgStk(arg->AsPutArgStk()); |
1438 | } |
1439 | args = args->gtOp.gtOp2; |
1440 | } |
1441 | } |
1442 | |
1443 | //------------------------------------------------------------------------ |
1444 | // ContainCheckIndir: Determine whether operands of an indir should be contained. |
1445 | // |
1446 | // Arguments: |
1447 | // node - The indirection node of interest |
1448 | // |
1449 | // Notes: |
1450 | // This is called for both store and load indirections. In the former case, it is assumed that |
1451 | // LowerStoreIndir() has already been called to check for RMW opportunities. |
1452 | // |
1453 | // Return Value: |
1454 | // None. |
1455 | // |
1456 | void Lowering::ContainCheckIndir(GenTreeIndir* node) |
1457 | { |
1458 | GenTree* addr = node->Addr(); |
1459 | |
1460 | // If this is the rhs of a block copy it will be handled when we handle the store. |
1461 | if (node->TypeGet() == TYP_STRUCT) |
1462 | { |
1463 | return; |
1464 | } |
1465 | |
1466 | #ifdef FEATURE_SIMD |
1467 | // If indirTree is of TYP_SIMD12, don't mark addr as contained |
1468 | // so that it always get computed to a register. This would |
1469 | // mean codegen side logic doesn't need to handle all possible |
1470 | // addr expressions that could be contained. |
1471 | // |
1472 | // TODO-XArch-CQ: handle other addr mode expressions that could be marked |
1473 | // as contained. |
1474 | if (node->TypeGet() == TYP_SIMD12) |
1475 | { |
1476 | return; |
1477 | } |
1478 | #endif // FEATURE_SIMD |
1479 | |
1480 | if ((node->gtFlags & GTF_IND_REQ_ADDR_IN_REG) != 0) |
1481 | { |
1482 | // The address of an indirection that requires its address in a reg. |
1483 | // Skip any further processing that might otherwise make it contained. |
1484 | } |
1485 | else if ((addr->OperGet() == GT_CLS_VAR_ADDR) || (addr->OperGet() == GT_LCL_VAR_ADDR)) |
1486 | { |
1487 | // These nodes go into an addr mode: |
1488 | // - GT_CLS_VAR_ADDR turns into a constant. |
1489 | // - GT_LCL_VAR_ADDR is a stack addr mode. |
1490 | |
1491 | // make this contained, it turns into a constant that goes into an addr mode |
1492 | MakeSrcContained(node, addr); |
1493 | } |
1494 | else if (addr->IsCnsIntOrI() && addr->AsIntConCommon()->FitsInAddrBase(comp)) |
1495 | { |
1496 | // Amd64: |
1497 | // We can mark any pc-relative 32-bit addr as containable, except for a direct VSD call address. |
1498 | // (i.e. those VSD calls for which stub addr is known during JIT compilation time). In this case, |
1499 | // VM requires us to pass stub addr in VirtualStubParam.reg - see LowerVirtualStubCall(). For |
1500 | // that reason we cannot mark such an addr as contained. Note that this is not an issue for |
1501 | // indirect VSD calls since morphArgs() is explicitly materializing hidden param as a non-standard |
1502 | // argument. |
1503 | // |
1504 | // Workaround: |
1505 | // Note that LowerVirtualStubCall() sets addr->gtRegNum to VirtualStubParam.reg and Lowering::doPhase() |
1506 | // sets destination candidates on such nodes and resets addr->gtRegNum to REG_NA. |
1507 | // Ideally we should set a flag on addr nodes that shouldn't be marked as contained |
1508 | // (in LowerVirtualStubCall()), but we don't have any GTF_* flags left for that purpose. As a workaround |
1509 | // an explicit check is made here. |
1510 | // |
1511 | // On x86, direct VSD is done via a relative branch, and in fact it MUST be contained. |
1512 | MakeSrcContained(node, addr); |
1513 | } |
1514 | else if ((addr->OperGet() == GT_LEA) && IsSafeToContainMem(node, addr)) |
1515 | { |
1516 | MakeSrcContained(node, addr); |
1517 | } |
1518 | } |
1519 | |
1520 | //------------------------------------------------------------------------ |
1521 | // ContainCheckStoreIndir: determine whether the sources of a STOREIND node should be contained. |
1522 | // |
1523 | // Arguments: |
1524 | // node - pointer to the node |
1525 | // |
1526 | void Lowering::ContainCheckStoreIndir(GenTreeIndir* node) |
1527 | { |
1528 | // If the source is a containable immediate, make it contained, unless it is |
1529 | // an int-size or larger store of zero to memory, because we can generate smaller code |
1530 | // by zeroing a register and then storing it. |
1531 | GenTree* src = node->gtOp.gtOp2; |
1532 | if (IsContainableImmed(node, src) && |
1533 | (!src->IsIntegralConst(0) || varTypeIsSmall(node) || node->gtGetOp1()->OperGet() == GT_CLS_VAR_ADDR)) |
1534 | { |
1535 | MakeSrcContained(node, src); |
1536 | } |
1537 | ContainCheckIndir(node); |
1538 | } |
1539 | |
1540 | //------------------------------------------------------------------------ |
1541 | // ContainCheckMul: determine whether the sources of a MUL node should be contained. |
1542 | // |
1543 | // Arguments: |
1544 | // node - pointer to the node |
1545 | // |
1546 | void Lowering::ContainCheckMul(GenTreeOp* node) |
1547 | { |
1548 | #if defined(_TARGET_X86_) |
1549 | assert(node->OperIs(GT_MUL, GT_MULHI, GT_MUL_LONG)); |
1550 | #else |
1551 | assert(node->OperIs(GT_MUL, GT_MULHI)); |
1552 | #endif |
1553 | |
1554 | // Case of float/double mul. |
1555 | if (varTypeIsFloating(node->TypeGet())) |
1556 | { |
1557 | ContainCheckFloatBinary(node); |
1558 | return; |
1559 | } |
1560 | |
1561 | GenTree* op1 = node->gtOp.gtOp1; |
1562 | GenTree* op2 = node->gtOp.gtOp2; |
1563 | |
1564 | bool isSafeToContainOp1 = true; |
1565 | bool isSafeToContainOp2 = true; |
1566 | |
1567 | bool isUnsignedMultiply = ((node->gtFlags & GTF_UNSIGNED) != 0); |
1568 | bool requiresOverflowCheck = node->gtOverflowEx(); |
1569 | bool useLeaEncoding = false; |
1570 | GenTree* memOp = nullptr; |
1571 | |
1572 | bool hasImpliedFirstOperand = false; |
1573 | GenTreeIntConCommon* imm = nullptr; |
1574 | GenTree* other = nullptr; |
1575 | |
1576 | // Multiply should never be using small types |
1577 | assert(!varTypeIsSmall(node->TypeGet())); |
1578 | |
1579 | // We do use the widening multiply to implement |
1580 | // the overflow checking for unsigned multiply |
1581 | // |
1582 | if (isUnsignedMultiply && requiresOverflowCheck) |
1583 | { |
1584 | hasImpliedFirstOperand = true; |
1585 | } |
1586 | else if (node->OperGet() == GT_MULHI) |
1587 | { |
1588 | hasImpliedFirstOperand = true; |
1589 | } |
1590 | #if defined(_TARGET_X86_) |
1591 | else if (node->OperGet() == GT_MUL_LONG) |
1592 | { |
1593 | hasImpliedFirstOperand = true; |
1594 | } |
1595 | #endif |
1596 | else if (IsContainableImmed(node, op2) || IsContainableImmed(node, op1)) |
1597 | { |
1598 | if (IsContainableImmed(node, op2)) |
1599 | { |
1600 | imm = op2->AsIntConCommon(); |
1601 | other = op1; |
1602 | } |
1603 | else |
1604 | { |
1605 | imm = op1->AsIntConCommon(); |
1606 | other = op2; |
1607 | } |
1608 | |
1609 | // CQ: We want to rewrite this into a LEA |
1610 | ssize_t immVal = imm->AsIntConCommon()->IconValue(); |
1611 | if (!requiresOverflowCheck && (immVal == 3 || immVal == 5 || immVal == 9)) |
1612 | { |
1613 | useLeaEncoding = true; |
1614 | } |
1615 | |
1616 | MakeSrcContained(node, imm); // The imm is always contained |
1617 | if (IsContainableMemoryOp(other)) |
1618 | { |
1619 | memOp = other; // memOp may be contained below |
1620 | } |
1621 | } |
1622 | |
1623 | // We allow one operand to be a contained memory operand. |
1624 | // The memory op type must match with the 'node' type. |
1625 | // This is because during codegen we use 'node' type to derive EmitTypeSize. |
1626 | // E.g op1 type = byte, op2 type = byte but GT_MUL node type is int. |
1627 | // |
1628 | if (memOp == nullptr) |
1629 | { |
1630 | if ((op2->TypeGet() == node->TypeGet()) && IsContainableMemoryOp(op2)) |
1631 | { |
1632 | isSafeToContainOp2 = IsSafeToContainMem(node, op2); |
1633 | if (isSafeToContainOp2) |
1634 | { |
1635 | memOp = op2; |
1636 | } |
1637 | } |
1638 | |
1639 | if ((memOp == nullptr) && (op1->TypeGet() == node->TypeGet()) && IsContainableMemoryOp(op1)) |
1640 | { |
1641 | isSafeToContainOp1 = IsSafeToContainMem(node, op1); |
1642 | if (isSafeToContainOp1) |
1643 | { |
1644 | memOp = op1; |
1645 | } |
1646 | } |
1647 | } |
1648 | else |
1649 | { |
1650 | if ((memOp->TypeGet() != node->TypeGet())) |
1651 | { |
1652 | memOp = nullptr; |
1653 | } |
1654 | else if (!IsSafeToContainMem(node, memOp)) |
1655 | { |
1656 | if (memOp == op1) |
1657 | { |
1658 | isSafeToContainOp1 = false; |
1659 | } |
1660 | else |
1661 | { |
1662 | isSafeToContainOp2 = false; |
1663 | } |
1664 | memOp = nullptr; |
1665 | } |
1666 | } |
1667 | // To generate an LEA we need to force memOp into a register |
1668 | // so don't allow memOp to be 'contained' |
1669 | // |
1670 | if (!useLeaEncoding) |
1671 | { |
1672 | if (memOp != nullptr) |
1673 | { |
1674 | MakeSrcContained(node, memOp); |
1675 | } |
1676 | else |
1677 | { |
1678 | // IsSafeToContainMem is expensive so we call it at most once for each operand |
1679 | // in this method. If we already called IsSafeToContainMem, it must have returned false; |
1680 | // otherwise, memOp would be set to the corresponding operand (op1 or op2). |
1681 | if (imm != nullptr) |
1682 | { |
1683 | // Has a contained immediate operand. |
1684 | // Only 'other' operand can be marked as reg optional. |
1685 | assert(other != nullptr); |
1686 | |
1687 | isSafeToContainOp1 = ((other == op1) && isSafeToContainOp1 && IsSafeToContainMem(node, op1)); |
1688 | isSafeToContainOp2 = ((other == op2) && isSafeToContainOp2 && IsSafeToContainMem(node, op2)); |
1689 | } |
1690 | else if (hasImpliedFirstOperand) |
1691 | { |
1692 | // Only op2 can be marked as reg optional. |
1693 | isSafeToContainOp1 = false; |
1694 | isSafeToContainOp2 = isSafeToContainOp2 && IsSafeToContainMem(node, op2); |
1695 | } |
1696 | else |
1697 | { |
1698 | // If there are no containable operands, we can make either of op1 or op2 |
1699 | // as reg optional. |
1700 | isSafeToContainOp1 = isSafeToContainOp1 && IsSafeToContainMem(node, op1); |
1701 | isSafeToContainOp2 = isSafeToContainOp2 && IsSafeToContainMem(node, op2); |
1702 | } |
1703 | SetRegOptionalForBinOp(node, isSafeToContainOp1, isSafeToContainOp2); |
1704 | } |
1705 | } |
1706 | } |
1707 | |
1708 | //------------------------------------------------------------------------ |
1709 | // ContainCheckDivOrMod: determine which operands of a div/mod should be contained. |
1710 | // |
1711 | // Arguments: |
1712 | // node - pointer to the node |
1713 | // |
1714 | void Lowering::ContainCheckDivOrMod(GenTreeOp* node) |
1715 | { |
1716 | assert(node->OperIs(GT_DIV, GT_MOD, GT_UDIV, GT_UMOD)); |
1717 | |
1718 | if (varTypeIsFloating(node->TypeGet())) |
1719 | { |
1720 | ContainCheckFloatBinary(node); |
1721 | return; |
1722 | } |
1723 | |
1724 | GenTree* dividend = node->gtGetOp1(); |
1725 | GenTree* divisor = node->gtGetOp2(); |
1726 | |
1727 | bool divisorCanBeRegOptional = true; |
1728 | #ifdef _TARGET_X86_ |
1729 | if (dividend->OperGet() == GT_LONG) |
1730 | { |
1731 | divisorCanBeRegOptional = false; |
1732 | MakeSrcContained(node, dividend); |
1733 | } |
1734 | #endif |
1735 | |
1736 | // divisor can be an r/m, but the memory indirection must be of the same size as the divide |
1737 | if (IsContainableMemoryOp(divisor) && (divisor->TypeGet() == node->TypeGet())) |
1738 | { |
1739 | MakeSrcContained(node, divisor); |
1740 | } |
1741 | else if (divisorCanBeRegOptional) |
1742 | { |
1743 | // If there are no containable operands, we can make an operand reg optional. |
1744 | // Div instruction allows only divisor to be a memory op. |
1745 | divisor->SetRegOptional(); |
1746 | } |
1747 | } |
1748 | |
1749 | //------------------------------------------------------------------------ |
1750 | // ContainCheckShiftRotate: determine whether the sources of a shift/rotate node should be contained. |
1751 | // |
1752 | // Arguments: |
1753 | // node - pointer to the node |
1754 | // |
1755 | void Lowering::ContainCheckShiftRotate(GenTreeOp* node) |
1756 | { |
1757 | assert(node->OperIsShiftOrRotate()); |
1758 | #ifdef _TARGET_X86_ |
1759 | GenTree* source = node->gtOp1; |
1760 | if (node->OperIsShiftLong()) |
1761 | { |
1762 | assert(source->OperGet() == GT_LONG); |
1763 | MakeSrcContained(node, source); |
1764 | } |
1765 | #endif // !_TARGET_X86_ |
1766 | |
1767 | GenTree* shiftBy = node->gtOp2; |
1768 | if (IsContainableImmed(node, shiftBy) && (shiftBy->gtIntConCommon.IconValue() <= 255) && |
1769 | (shiftBy->gtIntConCommon.IconValue() >= 0)) |
1770 | { |
1771 | MakeSrcContained(node, shiftBy); |
1772 | } |
1773 | } |
1774 | |
1775 | //------------------------------------------------------------------------ |
1776 | // ContainCheckStoreLoc: determine whether the source of a STORE_LCL* should be contained. |
1777 | // |
1778 | // Arguments: |
1779 | // node - pointer to the node |
1780 | // |
1781 | void Lowering::ContainCheckStoreLoc(GenTreeLclVarCommon* storeLoc) |
1782 | { |
1783 | assert(storeLoc->OperIsLocalStore()); |
1784 | GenTree* op1 = storeLoc->gtGetOp1(); |
1785 | |
1786 | #ifdef FEATURE_SIMD |
1787 | if (varTypeIsSIMD(storeLoc)) |
1788 | { |
1789 | if (op1->IsCnsIntOrI()) |
1790 | { |
1791 | // For an InitBlk we want op1 to be contained; otherwise we want it to |
1792 | // be evaluated into an xmm register. |
1793 | MakeSrcContained(storeLoc, op1); |
1794 | } |
1795 | return; |
1796 | } |
1797 | #endif // FEATURE_SIMD |
1798 | |
1799 | // If the source is a containable immediate, make it contained, unless it is |
1800 | // an int-size or larger store of zero to memory, because we can generate smaller code |
1801 | // by zeroing a register and then storing it. |
1802 | if (IsContainableImmed(storeLoc, op1) && (!op1->IsIntegralConst(0) || varTypeIsSmall(storeLoc))) |
1803 | { |
1804 | MakeSrcContained(storeLoc, op1); |
1805 | } |
1806 | #ifdef _TARGET_X86_ |
1807 | else if (op1->OperGet() == GT_LONG) |
1808 | { |
1809 | MakeSrcContained(storeLoc, op1); |
1810 | } |
1811 | #endif // _TARGET_X86_ |
1812 | } |
1813 | |
1814 | //------------------------------------------------------------------------ |
1815 | // ContainCheckCast: determine whether the source of a CAST node should be contained. |
1816 | // |
1817 | // Arguments: |
1818 | // node - pointer to the node |
1819 | // |
1820 | void Lowering::ContainCheckCast(GenTreeCast* node) |
1821 | { |
1822 | GenTree* castOp = node->CastOp(); |
1823 | var_types castToType = node->CastToType(); |
1824 | var_types srcType = castOp->TypeGet(); |
1825 | |
1826 | // force the srcType to unsigned if GT_UNSIGNED flag is set |
1827 | if (node->gtFlags & GTF_UNSIGNED) |
1828 | { |
1829 | srcType = genUnsignedType(srcType); |
1830 | } |
1831 | |
1832 | if (!node->gtOverflow() && (varTypeIsFloating(castToType) || varTypeIsFloating(srcType))) |
1833 | { |
1834 | #ifdef DEBUG |
1835 | // If converting to float/double, the operand must be 4 or 8 byte in size. |
1836 | if (varTypeIsFloating(castToType)) |
1837 | { |
1838 | unsigned opSize = genTypeSize(srcType); |
1839 | assert(opSize == 4 || opSize == 8); |
1840 | } |
1841 | #endif // DEBUG |
1842 | |
1843 | // U8 -> R8 conversion requires that the operand be in a register. |
1844 | if (srcType != TYP_ULONG) |
1845 | { |
1846 | if (IsContainableMemoryOp(castOp) || castOp->IsCnsNonZeroFltOrDbl()) |
1847 | { |
1848 | MakeSrcContained(node, castOp); |
1849 | } |
1850 | else |
1851 | { |
1852 | // Mark castOp as reg optional to indicate codegen |
1853 | // can still generate code if it is on stack. |
1854 | castOp->SetRegOptional(); |
1855 | } |
1856 | } |
1857 | } |
1858 | #if !defined(_TARGET_64BIT_) |
1859 | if (varTypeIsLong(srcType)) |
1860 | { |
1861 | noway_assert(castOp->OperGet() == GT_LONG); |
1862 | castOp->SetContained(); |
1863 | } |
1864 | #endif // !defined(_TARGET_64BIT_) |
1865 | } |
1866 | |
1867 | //------------------------------------------------------------------------ |
1868 | // ContainCheckCompare: determine whether the sources of a compare node should be contained. |
1869 | // |
1870 | // Arguments: |
1871 | // node - pointer to the node |
1872 | // |
1873 | void Lowering::ContainCheckCompare(GenTreeOp* cmp) |
1874 | { |
1875 | assert(cmp->OperIsCompare() || cmp->OperIs(GT_CMP)); |
1876 | |
1877 | GenTree* op1 = cmp->gtOp.gtOp1; |
1878 | GenTree* op2 = cmp->gtOp.gtOp2; |
1879 | var_types op1Type = op1->TypeGet(); |
1880 | var_types op2Type = op2->TypeGet(); |
1881 | |
1882 | // If either of op1 or op2 is floating point values, then we need to use |
1883 | // ucomiss or ucomisd to compare, both of which support the following form: |
1884 | // ucomis[s|d] xmm, xmm/mem |
1885 | // That is only the second operand can be a memory op. |
1886 | // |
1887 | // Second operand is a memory Op: Note that depending on comparison operator, |
1888 | // the operands of ucomis[s|d] need to be reversed. Therefore, either op1 or |
1889 | // op2 can be a memory op depending on the comparison operator. |
1890 | if (varTypeIsFloating(op1Type)) |
1891 | { |
1892 | // The type of the operands has to be the same and no implicit conversions at this stage. |
1893 | assert(op1Type == op2Type); |
1894 | |
1895 | bool reverseOps; |
1896 | if ((cmp->gtFlags & GTF_RELOP_NAN_UN) != 0) |
1897 | { |
1898 | // Unordered comparison case |
1899 | reverseOps = cmp->OperIs(GT_GT, GT_GE); |
1900 | } |
1901 | else |
1902 | { |
1903 | reverseOps = cmp->OperIs(GT_LT, GT_LE); |
1904 | } |
1905 | |
1906 | GenTree* otherOp; |
1907 | if (reverseOps) |
1908 | { |
1909 | otherOp = op1; |
1910 | } |
1911 | else |
1912 | { |
1913 | otherOp = op2; |
1914 | } |
1915 | |
1916 | assert(otherOp != nullptr); |
1917 | bool isSafeToContainOtherOp = true; |
1918 | if (otherOp->IsCnsNonZeroFltOrDbl()) |
1919 | { |
1920 | MakeSrcContained(cmp, otherOp); |
1921 | } |
1922 | else if (IsContainableMemoryOp(otherOp)) |
1923 | { |
1924 | isSafeToContainOtherOp = IsSafeToContainMem(cmp, otherOp); |
1925 | if (isSafeToContainOtherOp) |
1926 | { |
1927 | MakeSrcContained(cmp, otherOp); |
1928 | } |
1929 | } |
1930 | |
1931 | if (!otherOp->isContained() && isSafeToContainOtherOp && IsSafeToContainMem(cmp, otherOp)) |
1932 | { |
1933 | // SSE2 allows only otherOp to be a memory-op. Since otherOp is not |
1934 | // contained, we can mark it reg-optional. |
1935 | // IsSafeToContainMem is expensive so we call it at most once for otherOp. |
1936 | // If we already called IsSafeToContainMem, it must have returned false; |
1937 | // otherwise, otherOp would be contained. |
1938 | otherOp->SetRegOptional(); |
1939 | } |
1940 | |
1941 | return; |
1942 | } |
1943 | |
1944 | // TODO-XArch-CQ: factor out cmp optimization in 'genCondSetFlags' to be used here |
1945 | // or in other backend. |
1946 | |
1947 | if (CheckImmedAndMakeContained(cmp, op2)) |
1948 | { |
1949 | // If the types are the same, or if the constant is of the correct size, |
1950 | // we can treat the MemoryOp as contained. |
1951 | if (op1Type == op2Type) |
1952 | { |
1953 | if (IsContainableMemoryOp(op1)) |
1954 | { |
1955 | MakeSrcContained(cmp, op1); |
1956 | } |
1957 | else |
1958 | { |
1959 | op1->SetRegOptional(); |
1960 | } |
1961 | } |
1962 | } |
1963 | else if (op1Type == op2Type) |
1964 | { |
1965 | // Note that TEST does not have a r,rm encoding like CMP has but we can still |
1966 | // contain the second operand because the emitter maps both r,rm and rm,r to |
1967 | // the same instruction code. This avoids the need to special case TEST here. |
1968 | |
1969 | bool isSafeToContainOp1 = true; |
1970 | bool isSafeToContainOp2 = true; |
1971 | |
1972 | if (IsContainableMemoryOp(op2)) |
1973 | { |
1974 | isSafeToContainOp2 = IsSafeToContainMem(cmp, op2); |
1975 | if (isSafeToContainOp2) |
1976 | { |
1977 | MakeSrcContained(cmp, op2); |
1978 | } |
1979 | } |
1980 | |
1981 | if (!op2->isContained() && IsContainableMemoryOp(op1)) |
1982 | { |
1983 | isSafeToContainOp1 = IsSafeToContainMem(cmp, op1); |
1984 | if (isSafeToContainOp1) |
1985 | { |
1986 | MakeSrcContained(cmp, op1); |
1987 | } |
1988 | } |
1989 | |
1990 | if (!op1->isContained() && !op2->isContained()) |
1991 | { |
1992 | // One of op1 or op2 could be marked as reg optional |
1993 | // to indicate that codegen can still generate code |
1994 | // if one of them is on stack. |
1995 | GenTree* regOptionalCandidate = op1->IsCnsIntOrI() ? op2 : PreferredRegOptionalOperand(cmp); |
1996 | |
1997 | // IsSafeToContainMem is expensive so we call it at most once for each operand |
1998 | // in this method. If we already called IsSafeToContainMem, it must have returned false; |
1999 | // otherwise, the corresponding operand (op1 or op2) would be contained. |
2000 | bool setRegOptional = (regOptionalCandidate == op1) ? isSafeToContainOp1 && IsSafeToContainMem(cmp, op1) |
2001 | : isSafeToContainOp2 && IsSafeToContainMem(cmp, op2); |
2002 | if (setRegOptional) |
2003 | { |
2004 | regOptionalCandidate->SetRegOptional(); |
2005 | } |
2006 | } |
2007 | } |
2008 | } |
2009 | |
2010 | //------------------------------------------------------------------------ |
2011 | // LowerRMWMemOp: Determine if this is a valid RMW mem op, and if so lower it accordingly |
2012 | // |
2013 | // Arguments: |
2014 | // node - The indirect store node (GT_STORE_IND) of interest |
2015 | // |
2016 | // Return Value: |
2017 | // Returns true if 'node' is a valid RMW mem op; false otherwise. |
2018 | // |
2019 | bool Lowering::LowerRMWMemOp(GenTreeIndir* storeInd) |
2020 | { |
2021 | assert(storeInd->OperGet() == GT_STOREIND); |
2022 | |
2023 | // SSE2 doesn't support RMW on float values |
2024 | assert(!varTypeIsFloating(storeInd)); |
2025 | |
2026 | // Terminology: |
2027 | // indirDst = memory write of an addr mode (i.e. storeind destination) |
2028 | // indirSrc = value being written to memory (i.e. storeind source which could a binary/unary op) |
2029 | // indirCandidate = memory read i.e. a gtInd of an addr mode |
2030 | // indirOpSource = source operand used in binary/unary op (i.e. source operand of indirSrc node) |
2031 | |
2032 | GenTree* indirCandidate = nullptr; |
2033 | GenTree* indirOpSource = nullptr; |
2034 | |
2035 | if (!IsRMWMemOpRootedAtStoreInd(storeInd, &indirCandidate, &indirOpSource)) |
2036 | { |
2037 | JITDUMP("Lower of StoreInd didn't mark the node as self contained for reason: %d\n" , |
2038 | storeInd->AsStoreInd()->GetRMWStatus()); |
2039 | DISPTREERANGE(BlockRange(), storeInd); |
2040 | return false; |
2041 | } |
2042 | |
2043 | GenTree* indirDst = storeInd->gtGetOp1(); |
2044 | GenTree* indirSrc = storeInd->gtGetOp2(); |
2045 | genTreeOps oper = indirSrc->OperGet(); |
2046 | |
2047 | // At this point we have successfully detected a RMW memory op of one of the following forms |
2048 | // storeInd(indirDst, indirSrc(indirCandidate, indirOpSource)) OR |
2049 | // storeInd(indirDst, indirSrc(indirOpSource, indirCandidate) in case of commutative operations OR |
2050 | // storeInd(indirDst, indirSrc(indirCandidate) in case of unary operations |
2051 | // |
2052 | // Here indirSrc = one of the supported binary or unary operation for RMW of memory |
2053 | // indirCandidate = a GT_IND node |
2054 | // indirCandidateChild = operand of GT_IND indirCandidate |
2055 | // |
2056 | // The logic below does the following |
2057 | // Make indirOpSource contained. |
2058 | // Make indirSrc contained. |
2059 | // Make indirCandidate contained. |
2060 | // Make indirCandidateChild contained. |
2061 | // Make indirDst contained except when it is a GT_LCL_VAR or GT_CNS_INT that doesn't fit within addr |
2062 | // base. |
2063 | // |
2064 | |
2065 | // We have already done containment analysis on the indirSrc op. |
2066 | // If any of its operands are marked regOptional, reset that now. |
2067 | indirSrc->AsOp()->gtOp1->ClearRegOptional(); |
2068 | if (GenTree::OperIsBinary(oper)) |
2069 | { |
2070 | // On Xarch RMW operations require the source to be an immediate or in a register. |
2071 | // Therefore, if we have previously marked the indirOpSource as contained while lowering |
2072 | // the binary node, we need to reset that now. |
2073 | if (IsContainableMemoryOp(indirOpSource)) |
2074 | { |
2075 | indirOpSource->ClearContained(); |
2076 | } |
2077 | indirSrc->AsOp()->gtOp2->ClearRegOptional(); |
2078 | JITDUMP("Lower succesfully detected an assignment of the form: *addrMode BinOp= source\n" ); |
2079 | } |
2080 | else |
2081 | { |
2082 | assert(GenTree::OperIsUnary(oper)); |
2083 | JITDUMP("Lower succesfully detected an assignment of the form: *addrMode = UnaryOp(*addrMode)\n" ); |
2084 | } |
2085 | DISPTREERANGE(BlockRange(), storeInd); |
2086 | |
2087 | indirSrc->SetContained(); |
2088 | indirCandidate->SetContained(); |
2089 | |
2090 | GenTree* indirCandidateChild = indirCandidate->gtGetOp1(); |
2091 | indirCandidateChild->SetContained(); |
2092 | |
2093 | if (indirCandidateChild->OperGet() == GT_LEA) |
2094 | { |
2095 | GenTreeAddrMode* addrMode = indirCandidateChild->AsAddrMode(); |
2096 | |
2097 | if (addrMode->HasBase()) |
2098 | { |
2099 | assert(addrMode->Base()->OperIsLeaf()); |
2100 | addrMode->Base()->SetContained(); |
2101 | } |
2102 | |
2103 | if (addrMode->HasIndex()) |
2104 | { |
2105 | assert(addrMode->Index()->OperIsLeaf()); |
2106 | addrMode->Index()->SetContained(); |
2107 | } |
2108 | |
2109 | indirDst->SetContained(); |
2110 | } |
2111 | else |
2112 | { |
2113 | assert(indirCandidateChild->OperGet() == GT_LCL_VAR || indirCandidateChild->OperGet() == GT_LCL_VAR_ADDR || |
2114 | indirCandidateChild->OperGet() == GT_CLS_VAR_ADDR || indirCandidateChild->OperGet() == GT_CNS_INT); |
2115 | |
2116 | // If it is a GT_LCL_VAR, it still needs the reg to hold the address. |
2117 | // We would still need a reg for GT_CNS_INT if it doesn't fit within addressing mode base. |
2118 | // For GT_CLS_VAR_ADDR, we don't need a reg to hold the address, because field address value is known at jit |
2119 | // time. Also, we don't need a reg for GT_CLS_VAR_ADDR. |
2120 | if (indirCandidateChild->OperGet() == GT_LCL_VAR_ADDR || indirCandidateChild->OperGet() == GT_CLS_VAR_ADDR) |
2121 | { |
2122 | indirDst->SetContained(); |
2123 | } |
2124 | else if (indirCandidateChild->IsCnsIntOrI() && indirCandidateChild->AsIntConCommon()->FitsInAddrBase(comp)) |
2125 | { |
2126 | indirDst->SetContained(); |
2127 | } |
2128 | } |
2129 | return true; |
2130 | } |
2131 | |
2132 | //------------------------------------------------------------------------ |
2133 | // ContainCheckBinary: Determine whether a binary op's operands should be contained. |
2134 | // |
2135 | // Arguments: |
2136 | // node - the node we care about |
2137 | // |
2138 | void Lowering::ContainCheckBinary(GenTreeOp* node) |
2139 | { |
2140 | assert(node->OperIsBinary()); |
2141 | |
2142 | if (varTypeIsFloating(node)) |
2143 | { |
2144 | assert(node->OperIs(GT_ADD, GT_SUB)); |
2145 | ContainCheckFloatBinary(node); |
2146 | return; |
2147 | } |
2148 | |
2149 | GenTree* op1 = node->gtOp1; |
2150 | GenTree* op2 = node->gtOp2; |
2151 | |
2152 | // We can directly encode the second operand if it is either a containable constant or a memory-op. |
2153 | // In case of memory-op, we can encode it directly provided its type matches with 'tree' type. |
2154 | // This is because during codegen, type of 'tree' is used to determine emit Type size. If the types |
2155 | // do not match, they get normalized (i.e. sign/zero extended) on load into a register. |
2156 | bool directlyEncodable = false; |
2157 | bool binOpInRMW = false; |
2158 | GenTree* operand = nullptr; |
2159 | bool isSafeToContainOp1 = true; |
2160 | bool isSafeToContainOp2 = true; |
2161 | |
2162 | if (IsContainableImmed(node, op2)) |
2163 | { |
2164 | directlyEncodable = true; |
2165 | operand = op2; |
2166 | } |
2167 | else |
2168 | { |
2169 | binOpInRMW = IsBinOpInRMWStoreInd(node); |
2170 | if (!binOpInRMW) |
2171 | { |
2172 | const unsigned operatorSize = genTypeSize(node->TypeGet()); |
2173 | if ((genTypeSize(op2->TypeGet()) == operatorSize) && IsContainableMemoryOp(op2)) |
2174 | { |
2175 | isSafeToContainOp2 = IsSafeToContainMem(node, op2); |
2176 | if (isSafeToContainOp2) |
2177 | { |
2178 | directlyEncodable = true; |
2179 | operand = op2; |
2180 | } |
2181 | } |
2182 | |
2183 | if ((operand == nullptr) && node->OperIsCommutative()) |
2184 | { |
2185 | // If it is safe, we can reverse the order of operands of commutative operations for efficient |
2186 | // codegen |
2187 | if (IsContainableImmed(node, op1)) |
2188 | { |
2189 | directlyEncodable = true; |
2190 | operand = op1; |
2191 | } |
2192 | else if ((genTypeSize(op1->TypeGet()) == operatorSize) && IsContainableMemoryOp(op1)) |
2193 | { |
2194 | isSafeToContainOp1 = IsSafeToContainMem(node, op1); |
2195 | if (isSafeToContainOp1) |
2196 | { |
2197 | directlyEncodable = true; |
2198 | operand = op1; |
2199 | } |
2200 | } |
2201 | } |
2202 | } |
2203 | } |
2204 | |
2205 | if (directlyEncodable) |
2206 | { |
2207 | assert(operand != nullptr); |
2208 | MakeSrcContained(node, operand); |
2209 | } |
2210 | else if (!binOpInRMW) |
2211 | { |
2212 | // If this binary op neither has contained operands, nor is a |
2213 | // Read-Modify-Write (RMW) operation, we can mark its operands |
2214 | // as reg optional. |
2215 | |
2216 | // IsSafeToContainMem is expensive so we call it at most once for each operand |
2217 | // in this method. If we already called IsSafeToContainMem, it must have returned false; |
2218 | // otherwise, directlyEncodable would be true. |
2219 | isSafeToContainOp1 = isSafeToContainOp1 && IsSafeToContainMem(node, op1); |
2220 | isSafeToContainOp2 = isSafeToContainOp2 && IsSafeToContainMem(node, op2); |
2221 | |
2222 | SetRegOptionalForBinOp(node, isSafeToContainOp1, isSafeToContainOp2); |
2223 | } |
2224 | } |
2225 | |
2226 | //------------------------------------------------------------------------ |
2227 | // ContainCheckBoundsChk: determine whether any source of a bounds check node should be contained. |
2228 | // |
2229 | // Arguments: |
2230 | // node - pointer to the node |
2231 | // |
2232 | void Lowering::ContainCheckBoundsChk(GenTreeBoundsChk* node) |
2233 | { |
2234 | assert(node->OperIsBoundsCheck()); |
2235 | GenTree* other; |
2236 | if (CheckImmedAndMakeContained(node, node->gtIndex)) |
2237 | { |
2238 | other = node->gtArrLen; |
2239 | } |
2240 | else if (CheckImmedAndMakeContained(node, node->gtArrLen)) |
2241 | { |
2242 | other = node->gtIndex; |
2243 | } |
2244 | else if (IsContainableMemoryOp(node->gtIndex)) |
2245 | { |
2246 | other = node->gtIndex; |
2247 | } |
2248 | else |
2249 | { |
2250 | other = node->gtArrLen; |
2251 | } |
2252 | |
2253 | if (node->gtIndex->TypeGet() == node->gtArrLen->TypeGet()) |
2254 | { |
2255 | if (IsContainableMemoryOp(other)) |
2256 | { |
2257 | MakeSrcContained(node, other); |
2258 | } |
2259 | else |
2260 | { |
2261 | // We can mark 'other' as reg optional, since it is not contained. |
2262 | other->SetRegOptional(); |
2263 | } |
2264 | } |
2265 | } |
2266 | |
2267 | //------------------------------------------------------------------------ |
2268 | // ContainCheckIntrinsic: determine whether the source of an INTRINSIC node should be contained. |
2269 | // |
2270 | // Arguments: |
2271 | // node - pointer to the node |
2272 | // |
2273 | void Lowering::ContainCheckIntrinsic(GenTreeOp* node) |
2274 | { |
2275 | assert(node->OperIs(GT_INTRINSIC)); |
2276 | |
2277 | CorInfoIntrinsics intrinsicId = node->gtIntrinsic.gtIntrinsicId; |
2278 | |
2279 | if (intrinsicId == CORINFO_INTRINSIC_Sqrt || intrinsicId == CORINFO_INTRINSIC_Round || |
2280 | intrinsicId == CORINFO_INTRINSIC_Ceiling || intrinsicId == CORINFO_INTRINSIC_Floor) |
2281 | { |
2282 | GenTree* op1 = node->gtGetOp1(); |
2283 | if (IsContainableMemoryOp(op1) || op1->IsCnsNonZeroFltOrDbl()) |
2284 | { |
2285 | MakeSrcContained(node, op1); |
2286 | } |
2287 | else |
2288 | { |
2289 | // Mark the operand as reg optional since codegen can still |
2290 | // generate code if op1 is on stack. |
2291 | op1->SetRegOptional(); |
2292 | } |
2293 | } |
2294 | } |
2295 | |
2296 | #ifdef FEATURE_SIMD |
2297 | //---------------------------------------------------------------------------------------------- |
2298 | // ContainCheckSIMD: Perform containment analysis for a SIMD intrinsic node. |
2299 | // |
2300 | // Arguments: |
2301 | // simdNode - The SIMD intrinsic node. |
2302 | // |
2303 | void Lowering::ContainCheckSIMD(GenTreeSIMD* simdNode) |
2304 | { |
2305 | switch (simdNode->gtSIMDIntrinsicID) |
2306 | { |
2307 | GenTree* op1; |
2308 | GenTree* op2; |
2309 | |
2310 | case SIMDIntrinsicInit: |
2311 | { |
2312 | op1 = simdNode->gtOp.gtOp1; |
2313 | #ifndef _TARGET_64BIT_ |
2314 | if (op1->OperGet() == GT_LONG) |
2315 | { |
2316 | MakeSrcContained(simdNode, op1); |
2317 | GenTree* op1lo = op1->gtGetOp1(); |
2318 | GenTree* op1hi = op1->gtGetOp2(); |
2319 | |
2320 | if ((op1lo->IsIntegralConst(0) && op1hi->IsIntegralConst(0)) || |
2321 | (op1lo->IsIntegralConst(-1) && op1hi->IsIntegralConst(-1))) |
2322 | { |
2323 | MakeSrcContained(op1, op1lo); |
2324 | MakeSrcContained(op1, op1hi); |
2325 | } |
2326 | } |
2327 | else |
2328 | #endif // !_TARGET_64BIT_ |
2329 | if (op1->IsFPZero() || op1->IsIntegralConst(0) || |
2330 | (varTypeIsIntegral(simdNode->gtSIMDBaseType) && op1->IsIntegralConst(-1))) |
2331 | { |
2332 | MakeSrcContained(simdNode, op1); |
2333 | } |
2334 | else if ((comp->getSIMDSupportLevel() == SIMD_AVX2_Supported) && |
2335 | ((simdNode->gtSIMDSize == 16) || (simdNode->gtSIMDSize == 32))) |
2336 | { |
2337 | // Either op1 is a float or dbl constant or an addr |
2338 | if (op1->IsCnsFltOrDbl() || op1->OperIsLocalAddr()) |
2339 | { |
2340 | MakeSrcContained(simdNode, op1); |
2341 | } |
2342 | } |
2343 | } |
2344 | break; |
2345 | |
2346 | case SIMDIntrinsicInitArray: |
2347 | // We have an array and an index, which may be contained. |
2348 | CheckImmedAndMakeContained(simdNode, simdNode->gtGetOp2()); |
2349 | break; |
2350 | |
2351 | case SIMDIntrinsicOpEquality: |
2352 | case SIMDIntrinsicOpInEquality: |
2353 | // On SSE4/AVX, we can generate optimal code for (in)equality |
2354 | // against zero using ptest. We can safely do this optimization |
2355 | // for integral vectors but not for floating-point for the reason |
2356 | // that we have +0.0 and -0.0 and +0.0 == -0.0 |
2357 | op2 = simdNode->gtGetOp2(); |
2358 | if ((comp->getSIMDSupportLevel() >= SIMD_SSE4_Supported) && op2->IsIntegralConstVector(0)) |
2359 | { |
2360 | MakeSrcContained(simdNode, op2); |
2361 | } |
2362 | break; |
2363 | |
2364 | case SIMDIntrinsicGetItem: |
2365 | { |
2366 | // This implements get_Item method. The sources are: |
2367 | // - the source SIMD struct |
2368 | // - index (which element to get) |
2369 | // The result is baseType of SIMD struct. |
2370 | op1 = simdNode->gtOp.gtOp1; |
2371 | op2 = simdNode->gtOp.gtOp2; |
2372 | |
2373 | if (op1->OperGet() == GT_IND) |
2374 | { |
2375 | assert((op1->gtFlags & GTF_IND_REQ_ADDR_IN_REG) != 0); |
2376 | op1->AsIndir()->Addr()->ClearContained(); |
2377 | } |
2378 | // If the index is a constant, mark it as contained. |
2379 | CheckImmedAndMakeContained(simdNode, op2); |
2380 | |
2381 | if (IsContainableMemoryOp(op1)) |
2382 | { |
2383 | MakeSrcContained(simdNode, op1); |
2384 | if (op1->OperGet() == GT_IND) |
2385 | { |
2386 | op1->AsIndir()->Addr()->ClearContained(); |
2387 | } |
2388 | } |
2389 | } |
2390 | break; |
2391 | |
2392 | case SIMDIntrinsicShuffleSSE2: |
2393 | // Second operand is an integer constant and marked as contained. |
2394 | assert(simdNode->gtOp.gtOp2->IsCnsIntOrI()); |
2395 | MakeSrcContained(simdNode, simdNode->gtOp.gtOp2); |
2396 | break; |
2397 | |
2398 | default: |
2399 | break; |
2400 | } |
2401 | } |
2402 | #endif // FEATURE_SIMD |
2403 | |
2404 | #ifdef FEATURE_HW_INTRINSICS |
2405 | //---------------------------------------------------------------------------------------------- |
2406 | // IsContainableHWIntrinsicOp: Return true if 'node' is a containable HWIntrinsic op. |
2407 | // |
2408 | // Arguments: |
2409 | // containingNode - The hardware intrinsic node which contains 'node' |
2410 | // node - The node to check |
2411 | // [Out] supportsRegOptional - On return, this will be true if 'containingNode' supports regOptional operands; |
2412 | // otherwise, false. |
2413 | // |
2414 | // Return Value: |
2415 | // true if 'node' is a containable hardware intrinsic node; otherwise, false. |
2416 | // |
2417 | bool Lowering::IsContainableHWIntrinsicOp(GenTreeHWIntrinsic* containingNode, GenTree* node, bool* supportsRegOptional) |
2418 | { |
2419 | NamedIntrinsic containingIntrinsicId = containingNode->gtHWIntrinsicId; |
2420 | HWIntrinsicCategory category = HWIntrinsicInfo::lookupCategory(containingIntrinsicId); |
2421 | |
2422 | // We shouldn't have called in here if containingNode doesn't support containment |
2423 | assert(HWIntrinsicInfo::SupportsContainment(containingIntrinsicId)); |
2424 | |
2425 | // containingNode supports nodes that read from an aligned memory address |
2426 | // |
2427 | // This will generally be an explicit LoadAligned instruction and is generally |
2428 | // false for machines with VEX support. This is because there is currently no way |
2429 | // to guarantee that the address read from will always be aligned and we could silently |
2430 | // change the behavior of the program in the case where an Access Violation would have |
2431 | // otherwise occurred. |
2432 | bool supportsAlignedSIMDLoads = false; |
2433 | |
2434 | // containingNode supports nodes that read from general memory |
2435 | // |
2436 | // We currently have to assume all "general" loads are unaligned. As such, this is |
2437 | // generally used to determine if we can mark the node as `regOptional` in the case |
2438 | // where `node` is not containable. However, this can also be used to determine whether |
2439 | // we can mark other types of reads as contained (such as when directly reading a local). |
2440 | bool supportsGeneralLoads = false; |
2441 | |
2442 | // containingNode supports nodes that read from a scalar memory address |
2443 | // |
2444 | // This will generally be an explicit LoadScalar instruction but is also used to determine |
2445 | // whether we can read an address of type T (we don't support this when the load would |
2446 | // read more than sizeof(T) bytes). |
2447 | bool supportsSIMDScalarLoads = false; |
2448 | |
2449 | // containingNode supports nodes that read from an unaligned memory address |
2450 | // |
2451 | // This will generally be an explicit Load instruction and is generally false for machines |
2452 | // without VEX support. This is because older hardware required that the SIMD operand always |
2453 | // be aligned to the 'natural alignment' of the type. |
2454 | bool supportsUnalignedSIMDLoads = false; |
2455 | |
2456 | switch (category) |
2457 | { |
2458 | case HW_Category_SimpleSIMD: |
2459 | { |
2460 | // These intrinsics only expect 16 or 32-byte nodes for containment |
2461 | assert((genTypeSize(node->TypeGet()) == 16) || (genTypeSize(node->TypeGet()) == 32)); |
2462 | assert(supportsSIMDScalarLoads == false); |
2463 | |
2464 | supportsAlignedSIMDLoads = |
2465 | !comp->canUseVexEncoding() && (containingIntrinsicId != NI_SSE2_ConvertToVector128Double); |
2466 | supportsUnalignedSIMDLoads = !supportsAlignedSIMDLoads; |
2467 | supportsGeneralLoads = supportsUnalignedSIMDLoads; |
2468 | |
2469 | break; |
2470 | } |
2471 | |
2472 | case HW_Category_IMM: |
2473 | { |
2474 | switch (containingIntrinsicId) |
2475 | { |
2476 | case NI_SSE_Shuffle: |
2477 | case NI_SSE2_CompareLessThan: |
2478 | case NI_SSE2_ShiftLeftLogical: |
2479 | case NI_SSE2_ShiftRightArithmetic: |
2480 | case NI_SSE2_ShiftRightLogical: |
2481 | case NI_SSE2_Shuffle: |
2482 | case NI_SSE2_ShuffleHigh: |
2483 | case NI_SSE2_ShuffleLow: |
2484 | case NI_SSSE3_AlignRight: |
2485 | case NI_SSE41_Blend: |
2486 | case NI_SSE41_DotProduct: |
2487 | case NI_SSE41_MultipleSumAbsoluteDifferences: |
2488 | case NI_AES_KeygenAssist: |
2489 | case NI_PCLMULQDQ_CarrylessMultiply: |
2490 | case NI_AVX_Blend: |
2491 | case NI_AVX_Compare: |
2492 | case NI_AVX_DotProduct: |
2493 | case NI_AVX_InsertVector128: |
2494 | case NI_AVX_Permute: |
2495 | case NI_AVX_Permute2x128: |
2496 | case NI_AVX2_Blend: |
2497 | case NI_AVX2_InsertVector128: |
2498 | case NI_AVX2_MultipleSumAbsoluteDifferences: |
2499 | case NI_AVX2_Permute2x128: |
2500 | case NI_AVX2_Permute4x64: |
2501 | case NI_AVX2_ShiftLeftLogical: |
2502 | case NI_AVX2_ShiftRightArithmetic: |
2503 | case NI_AVX2_ShiftRightLogical: |
2504 | case NI_AVX2_ShuffleHigh: |
2505 | case NI_AVX2_ShuffleLow: |
2506 | { |
2507 | // These intrinsics only expect 16 or 32-byte nodes for containment |
2508 | assert((genTypeSize(node->TypeGet()) == 16) || (genTypeSize(node->TypeGet()) == 32)); |
2509 | assert(supportsSIMDScalarLoads == false); |
2510 | |
2511 | supportsAlignedSIMDLoads = !comp->canUseVexEncoding(); |
2512 | supportsUnalignedSIMDLoads = !supportsAlignedSIMDLoads; |
2513 | supportsGeneralLoads = supportsUnalignedSIMDLoads; |
2514 | |
2515 | break; |
2516 | } |
2517 | |
2518 | case NI_SSE2_Insert: |
2519 | case NI_SSE41_Insert: |
2520 | case NI_SSE41_X64_Insert: |
2521 | { |
2522 | if (containingNode->gtSIMDBaseType == TYP_FLOAT) |
2523 | { |
2524 | assert(containingIntrinsicId == NI_SSE41_Insert); |
2525 | assert(genTypeSize(node->TypeGet()) == 16); |
2526 | |
2527 | // Sse41.Insert(V128<float>, V128<float>, byte) is a bit special |
2528 | // in that it has different behavior depending on whether the |
2529 | // second operand is coming from a register or memory. When coming |
2530 | // from a register, all 4 elements of the vector can be used and it |
2531 | // is effectively a regular `SimpleSIMD` operation; but when loading |
2532 | // from memory, it only works with the lowest element and is effectively |
2533 | // a `SIMDScalar`. |
2534 | |
2535 | assert(supportsAlignedSIMDLoads == false); |
2536 | assert(supportsUnalignedSIMDLoads == false); |
2537 | assert(supportsGeneralLoads == false); |
2538 | assert(supportsSIMDScalarLoads == false); |
2539 | |
2540 | GenTree* op1 = containingNode->gtGetOp1(); |
2541 | GenTree* op2 = nullptr; |
2542 | GenTree* op3 = nullptr; |
2543 | |
2544 | assert(op1->OperIsList()); |
2545 | assert(containingNode->gtGetOp2() == nullptr); |
2546 | |
2547 | GenTreeArgList* argList = op1->AsArgList(); |
2548 | |
2549 | op1 = argList->Current(); |
2550 | argList = argList->Rest(); |
2551 | |
2552 | op2 = argList->Current(); |
2553 | argList = argList->Rest(); |
2554 | |
2555 | assert(node == op2); |
2556 | |
2557 | op3 = argList->Current(); |
2558 | |
2559 | // The upper two bits of the immediate value are ignored if |
2560 | // op2 comes from memory. In order to support using the upper |
2561 | // bits, we need to disable containment support if op3 is not |
2562 | // constant or if the constant is greater than 0x3F (which means |
2563 | // at least one of the upper two bits is set). |
2564 | |
2565 | if (op3->IsCnsIntOrI()) |
2566 | { |
2567 | ssize_t ival = op3->AsIntCon()->IconValue(); |
2568 | assert((ival >= 0) && (ival <= 255)); |
2569 | |
2570 | supportsSIMDScalarLoads = (ival <= 0x3F); |
2571 | supportsGeneralLoads = supportsSIMDScalarLoads; |
2572 | } |
2573 | break; |
2574 | } |
2575 | |
2576 | // We should only get here for integral nodes. |
2577 | assert(varTypeIsIntegral(node->TypeGet())); |
2578 | |
2579 | assert(supportsAlignedSIMDLoads == false); |
2580 | assert(supportsUnalignedSIMDLoads == false); |
2581 | assert(supportsSIMDScalarLoads == false); |
2582 | |
2583 | const unsigned expectedSize = genTypeSize(containingNode->gtSIMDBaseType); |
2584 | const unsigned operandSize = genTypeSize(node->TypeGet()); |
2585 | |
2586 | supportsGeneralLoads = (operandSize >= expectedSize); |
2587 | break; |
2588 | } |
2589 | |
2590 | case NI_AVX_CompareScalar: |
2591 | { |
2592 | // These intrinsics only expect 16 or 32-byte nodes for containment |
2593 | assert((genTypeSize(node->TypeGet()) == 16) || (genTypeSize(node->TypeGet()) == 32)); |
2594 | |
2595 | assert(supportsAlignedSIMDLoads == false); |
2596 | assert(supportsUnalignedSIMDLoads == false); |
2597 | |
2598 | supportsSIMDScalarLoads = true; |
2599 | supportsGeneralLoads = supportsSIMDScalarLoads; |
2600 | break; |
2601 | } |
2602 | |
2603 | default: |
2604 | { |
2605 | assert(supportsAlignedSIMDLoads == false); |
2606 | assert(supportsGeneralLoads == false); |
2607 | assert(supportsSIMDScalarLoads == false); |
2608 | assert(supportsUnalignedSIMDLoads == false); |
2609 | break; |
2610 | } |
2611 | } |
2612 | break; |
2613 | } |
2614 | |
2615 | case HW_Category_SIMDScalar: |
2616 | { |
2617 | assert(supportsAlignedSIMDLoads == false); |
2618 | assert(supportsUnalignedSIMDLoads == false); |
2619 | |
2620 | switch (containingIntrinsicId) |
2621 | { |
2622 | case NI_Base_Vector128_CreateScalarUnsafe: |
2623 | case NI_Base_Vector256_CreateScalarUnsafe: |
2624 | { |
2625 | assert(supportsSIMDScalarLoads == false); |
2626 | |
2627 | const unsigned expectedSize = genTypeSize(genActualType(containingNode->gtSIMDBaseType)); |
2628 | const unsigned operandSize = genTypeSize(node->TypeGet()); |
2629 | |
2630 | supportsGeneralLoads = (operandSize == expectedSize); |
2631 | break; |
2632 | } |
2633 | |
2634 | case NI_SSE_ConvertScalarToVector128Single: |
2635 | case NI_SSE2_ConvertScalarToVector128Double: |
2636 | case NI_SSE2_ConvertScalarToVector128Int32: |
2637 | case NI_SSE2_ConvertScalarToVector128UInt32: |
2638 | case NI_SSE_X64_ConvertScalarToVector128Single: |
2639 | case NI_SSE2_X64_ConvertScalarToVector128Double: |
2640 | case NI_SSE2_X64_ConvertScalarToVector128Int64: |
2641 | case NI_SSE2_X64_ConvertScalarToVector128UInt64: |
2642 | { |
2643 | if (!varTypeIsIntegral(node->TypeGet())) |
2644 | { |
2645 | // The floating-point overload doesn't require any special semantics |
2646 | assert(containingIntrinsicId == NI_SSE2_ConvertScalarToVector128Double); |
2647 | supportsSIMDScalarLoads = true; |
2648 | supportsGeneralLoads = supportsSIMDScalarLoads; |
2649 | break; |
2650 | } |
2651 | |
2652 | assert(supportsSIMDScalarLoads == false); |
2653 | |
2654 | const unsigned expectedSize = genTypeSize(genActualType(containingNode->gtSIMDBaseType)); |
2655 | const unsigned operandSize = genTypeSize(node->TypeGet()); |
2656 | |
2657 | supportsGeneralLoads = (operandSize == expectedSize); |
2658 | break; |
2659 | } |
2660 | |
2661 | default: |
2662 | { |
2663 | // These intrinsics only expect 16 or 32-byte nodes for containment |
2664 | assert((genTypeSize(node->TypeGet()) == 16) || (genTypeSize(node->TypeGet()) == 32)); |
2665 | |
2666 | supportsSIMDScalarLoads = true; |
2667 | supportsGeneralLoads = supportsSIMDScalarLoads; |
2668 | break; |
2669 | } |
2670 | } |
2671 | break; |
2672 | } |
2673 | |
2674 | case HW_Category_Scalar: |
2675 | { |
2676 | // We should only get here for integral nodes. |
2677 | assert(varTypeIsIntegral(node->TypeGet())); |
2678 | |
2679 | assert(supportsAlignedSIMDLoads == false); |
2680 | assert(supportsUnalignedSIMDLoads == false); |
2681 | assert(supportsSIMDScalarLoads == false); |
2682 | |
2683 | const unsigned expectedSize = genTypeSize(containingNode->TypeGet()); |
2684 | const unsigned operandSize = genTypeSize(node->TypeGet()); |
2685 | |
2686 | supportsGeneralLoads = (operandSize >= expectedSize); |
2687 | break; |
2688 | } |
2689 | |
2690 | default: |
2691 | { |
2692 | assert(supportsAlignedSIMDLoads == false); |
2693 | assert(supportsGeneralLoads == false); |
2694 | assert(supportsSIMDScalarLoads == false); |
2695 | assert(supportsUnalignedSIMDLoads == false); |
2696 | break; |
2697 | } |
2698 | } |
2699 | |
2700 | noway_assert(supportsRegOptional != nullptr); |
2701 | *supportsRegOptional = supportsGeneralLoads; |
2702 | |
2703 | if (!node->OperIsHWIntrinsic()) |
2704 | { |
2705 | return supportsGeneralLoads && IsContainableMemoryOp(node); |
2706 | } |
2707 | |
2708 | // TODO-XArch: Update this to be table driven, if possible. |
2709 | |
2710 | NamedIntrinsic intrinsicId = node->AsHWIntrinsic()->gtHWIntrinsicId; |
2711 | |
2712 | switch (intrinsicId) |
2713 | { |
2714 | case NI_SSE_LoadAlignedVector128: |
2715 | case NI_SSE2_LoadAlignedVector128: |
2716 | case NI_AVX_LoadAlignedVector256: |
2717 | { |
2718 | return supportsAlignedSIMDLoads; |
2719 | } |
2720 | |
2721 | case NI_SSE_LoadScalarVector128: |
2722 | case NI_SSE2_LoadScalarVector128: |
2723 | { |
2724 | return supportsSIMDScalarLoads; |
2725 | } |
2726 | |
2727 | // VEX encoding supports unaligned memory ops, so we can fold them |
2728 | case NI_SSE_LoadVector128: |
2729 | case NI_SSE2_LoadVector128: |
2730 | case NI_AVX_LoadVector256: |
2731 | { |
2732 | return supportsUnalignedSIMDLoads; |
2733 | } |
2734 | |
2735 | default: |
2736 | { |
2737 | assert(!node->isContainableHWIntrinsic()); |
2738 | return false; |
2739 | } |
2740 | } |
2741 | } |
2742 | |
2743 | //---------------------------------------------------------------------------------------------- |
2744 | // ContainCheckHWIntrinsic: Perform containment analysis for a hardware intrinsic node. |
2745 | // |
2746 | // Arguments: |
2747 | // node - The hardware intrinsic node. |
2748 | // |
2749 | void Lowering::ContainCheckHWIntrinsic(GenTreeHWIntrinsic* node) |
2750 | { |
2751 | NamedIntrinsic intrinsicId = node->gtHWIntrinsicId; |
2752 | HWIntrinsicCategory category = HWIntrinsicInfo::lookupCategory(intrinsicId); |
2753 | int numArgs = HWIntrinsicInfo::lookupNumArgs(node); |
2754 | var_types baseType = node->gtSIMDBaseType; |
2755 | |
2756 | GenTree* op1 = node->gtGetOp1(); |
2757 | GenTree* op2 = node->gtGetOp2(); |
2758 | GenTree* op3 = nullptr; |
2759 | |
2760 | if (!HWIntrinsicInfo::SupportsContainment(intrinsicId)) |
2761 | { |
2762 | // AVX2 gather are not contaibable and always have constant IMM argument |
2763 | if (HWIntrinsicInfo::isAVX2GatherIntrinsic(intrinsicId)) |
2764 | { |
2765 | GenTree* lastOp = HWIntrinsicInfo::lookupLastOp(node); |
2766 | assert(lastOp != nullptr); |
2767 | MakeSrcContained(node, lastOp); |
2768 | } |
2769 | // Exit early if containment isn't supported |
2770 | return; |
2771 | } |
2772 | |
2773 | // TODO-XArch-CQ: Non-VEX encoded instructions can have both ops contained |
2774 | |
2775 | const bool isCommutative = HWIntrinsicInfo::IsCommutative(intrinsicId); |
2776 | |
2777 | if (numArgs == 1) |
2778 | { |
2779 | // One argument intrinsics cannot be commutative |
2780 | assert(!isCommutative); |
2781 | |
2782 | assert(!op1->OperIsList()); |
2783 | assert(op2 == nullptr); |
2784 | |
2785 | switch (category) |
2786 | { |
2787 | case HW_Category_SimpleSIMD: |
2788 | case HW_Category_SIMDScalar: |
2789 | case HW_Category_Scalar: |
2790 | { |
2791 | switch (intrinsicId) |
2792 | { |
2793 | case NI_SSE_ReciprocalScalar: |
2794 | case NI_SSE_ReciprocalSqrtScalar: |
2795 | case NI_SSE_SqrtScalar: |
2796 | case NI_SSE2_SqrtScalar: |
2797 | case NI_SSE41_CeilingScalar: |
2798 | case NI_SSE41_FloorScalar: |
2799 | case NI_SSE41_RoundCurrentDirectionScalar: |
2800 | case NI_SSE41_RoundToNearestIntegerScalar: |
2801 | case NI_SSE41_RoundToNegativeInfinityScalar: |
2802 | case NI_SSE41_RoundToPositiveInfinityScalar: |
2803 | case NI_SSE41_RoundToZeroScalar: |
2804 | { |
2805 | // These intrinsics have both 1 and 2-operand overloads. |
2806 | // |
2807 | // The 1-operand overload basically does `intrinsic(op1, op1)` |
2808 | // |
2809 | // Because of this, the operand must be loaded into a register |
2810 | // and cannot be contained. |
2811 | return; |
2812 | } |
2813 | |
2814 | case NI_SSE2_ConvertToInt32: |
2815 | case NI_SSE2_X64_ConvertToInt64: |
2816 | case NI_SSE2_ConvertToUInt32: |
2817 | case NI_SSE2_X64_ConvertToUInt64: |
2818 | case NI_AVX2_ConvertToInt32: |
2819 | case NI_AVX2_ConvertToUInt32: |
2820 | { |
2821 | if (varTypeIsIntegral(baseType)) |
2822 | { |
2823 | // These intrinsics are "ins reg/mem, xmm" and don't |
2824 | // currently support containment. |
2825 | return; |
2826 | } |
2827 | |
2828 | break; |
2829 | } |
2830 | |
2831 | default: |
2832 | { |
2833 | break; |
2834 | } |
2835 | } |
2836 | |
2837 | bool supportsRegOptional = false; |
2838 | |
2839 | if (IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
2840 | { |
2841 | MakeSrcContained(node, op1); |
2842 | } |
2843 | else if (supportsRegOptional) |
2844 | { |
2845 | op1->SetRegOptional(); |
2846 | } |
2847 | break; |
2848 | } |
2849 | |
2850 | default: |
2851 | { |
2852 | unreached(); |
2853 | break; |
2854 | } |
2855 | } |
2856 | } |
2857 | else |
2858 | { |
2859 | if (numArgs == 2) |
2860 | { |
2861 | assert(!op1->OperIsList()); |
2862 | assert(op2 != nullptr); |
2863 | assert(!op2->OperIsList()); |
2864 | |
2865 | switch (category) |
2866 | { |
2867 | case HW_Category_SimpleSIMD: |
2868 | case HW_Category_SIMDScalar: |
2869 | case HW_Category_Scalar: |
2870 | { |
2871 | if (HWIntrinsicInfo::GeneratesMultipleIns(intrinsicId)) |
2872 | { |
2873 | switch (intrinsicId) |
2874 | { |
2875 | case NI_SSE_CompareLessThanOrderedScalar: |
2876 | case NI_SSE_CompareLessThanUnorderedScalar: |
2877 | case NI_SSE_CompareLessThanOrEqualOrderedScalar: |
2878 | case NI_SSE_CompareLessThanOrEqualUnorderedScalar: |
2879 | case NI_SSE2_CompareLessThanOrderedScalar: |
2880 | case NI_SSE2_CompareLessThanUnorderedScalar: |
2881 | case NI_SSE2_CompareLessThanOrEqualOrderedScalar: |
2882 | case NI_SSE2_CompareLessThanOrEqualUnorderedScalar: |
2883 | { |
2884 | // We need to swap the operands for CompareLessThanOrEqual |
2885 | node->gtOp1 = op2; |
2886 | node->gtOp2 = op1; |
2887 | op2 = op1; |
2888 | break; |
2889 | } |
2890 | |
2891 | default: |
2892 | { |
2893 | // TODO-XArch-CQ: The Compare*OrderedScalar and Compare*UnorderedScalar methods |
2894 | // are commutative if you also inverse the intrinsic. |
2895 | break; |
2896 | } |
2897 | } |
2898 | } |
2899 | |
2900 | bool supportsRegOptional = false; |
2901 | |
2902 | if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
2903 | { |
2904 | MakeSrcContained(node, op2); |
2905 | } |
2906 | else if ((isCommutative || (intrinsicId == NI_BMI2_MultiplyNoFlags) || |
2907 | (intrinsicId == NI_BMI2_X64_MultiplyNoFlags)) && |
2908 | IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
2909 | { |
2910 | MakeSrcContained(node, op1); |
2911 | |
2912 | // Swap the operands here to make the containment checks in codegen significantly simpler |
2913 | node->gtOp1 = op2; |
2914 | node->gtOp2 = op1; |
2915 | } |
2916 | else if (supportsRegOptional) |
2917 | { |
2918 | op2->SetRegOptional(); |
2919 | |
2920 | // TODO-XArch-CQ: For commutative nodes, either operand can be reg-optional. |
2921 | // https://github.com/dotnet/coreclr/issues/6361 |
2922 | } |
2923 | break; |
2924 | } |
2925 | |
2926 | case HW_Category_IMM: |
2927 | { |
2928 | // We don't currently have any IMM intrinsics which are also commutative |
2929 | assert(!isCommutative); |
2930 | bool supportsRegOptional = false; |
2931 | |
2932 | switch (intrinsicId) |
2933 | { |
2934 | case NI_SSE2_ShiftLeftLogical: |
2935 | case NI_SSE2_ShiftRightArithmetic: |
2936 | case NI_SSE2_ShiftRightLogical: |
2937 | case NI_AVX2_ShiftLeftLogical: |
2938 | case NI_AVX2_ShiftRightArithmetic: |
2939 | case NI_AVX2_ShiftRightLogical: |
2940 | { |
2941 | // These intrinsics can have op2 be imm or reg/mem |
2942 | |
2943 | if (!HWIntrinsicInfo::isImmOp(intrinsicId, op2)) |
2944 | { |
2945 | if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
2946 | { |
2947 | MakeSrcContained(node, op2); |
2948 | } |
2949 | else if (supportsRegOptional) |
2950 | { |
2951 | op2->SetRegOptional(); |
2952 | } |
2953 | } |
2954 | break; |
2955 | } |
2956 | |
2957 | case NI_SSE2_Shuffle: |
2958 | case NI_SSE2_ShuffleHigh: |
2959 | case NI_SSE2_ShuffleLow: |
2960 | case NI_AVX2_Permute4x64: |
2961 | { |
2962 | // These intrinsics have op2 as an imm and op1 as a reg/mem |
2963 | |
2964 | if (IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
2965 | { |
2966 | MakeSrcContained(node, op1); |
2967 | } |
2968 | else if (supportsRegOptional) |
2969 | { |
2970 | op1->SetRegOptional(); |
2971 | } |
2972 | break; |
2973 | } |
2974 | |
2975 | case NI_AVX_Permute: |
2976 | { |
2977 | // These intrinsics can have op2 be imm or reg/mem |
2978 | // They also can have op1 be reg/mem and op2 be imm |
2979 | |
2980 | if (HWIntrinsicInfo::isImmOp(intrinsicId, op2)) |
2981 | { |
2982 | if (IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
2983 | { |
2984 | MakeSrcContained(node, op1); |
2985 | } |
2986 | else if (supportsRegOptional) |
2987 | { |
2988 | op1->SetRegOptional(); |
2989 | } |
2990 | } |
2991 | else if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
2992 | { |
2993 | MakeSrcContained(node, op2); |
2994 | } |
2995 | else if (supportsRegOptional) |
2996 | { |
2997 | op2->SetRegOptional(); |
2998 | } |
2999 | break; |
3000 | } |
3001 | |
3002 | case NI_AES_KeygenAssist: |
3003 | { |
3004 | if (IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
3005 | { |
3006 | MakeSrcContained(node, op1); |
3007 | } |
3008 | else if (supportsRegOptional) |
3009 | { |
3010 | op1->SetRegOptional(); |
3011 | } |
3012 | break; |
3013 | } |
3014 | |
3015 | default: |
3016 | { |
3017 | break; |
3018 | } |
3019 | } |
3020 | |
3021 | break; |
3022 | } |
3023 | |
3024 | case HW_Category_Special: |
3025 | { |
3026 | if (intrinsicId == NI_SSE2_CompareLessThan) |
3027 | { |
3028 | bool supportsRegOptional = false; |
3029 | |
3030 | if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
3031 | { |
3032 | MakeSrcContained(node, op2); |
3033 | } |
3034 | else if (supportsRegOptional) |
3035 | { |
3036 | op2->SetRegOptional(); |
3037 | } |
3038 | } |
3039 | else |
3040 | { |
3041 | unreached(); |
3042 | } |
3043 | break; |
3044 | } |
3045 | |
3046 | default: |
3047 | { |
3048 | unreached(); |
3049 | break; |
3050 | } |
3051 | } |
3052 | } |
3053 | else if (numArgs == 3) |
3054 | { |
3055 | // three argument intrinsics should not be marked commutative |
3056 | assert(!isCommutative); |
3057 | |
3058 | assert(op1->OperIsList()); |
3059 | assert(op2 == nullptr); |
3060 | |
3061 | GenTreeArgList* argList = op1->AsArgList(); |
3062 | GenTreeArgList* originalArgList = argList; |
3063 | |
3064 | op1 = argList->Current(); |
3065 | argList = argList->Rest(); |
3066 | |
3067 | op2 = argList->Current(); |
3068 | argList = argList->Rest(); |
3069 | |
3070 | op3 = argList->Current(); |
3071 | assert(argList->Rest() == nullptr); |
3072 | |
3073 | switch (category) |
3074 | { |
3075 | case HW_Category_SimpleSIMD: |
3076 | case HW_Category_SIMDScalar: |
3077 | case HW_Category_Scalar: |
3078 | { |
3079 | if ((intrinsicId >= NI_FMA_MultiplyAdd) && (intrinsicId <= NI_FMA_MultiplySubtractNegatedScalar)) |
3080 | { |
3081 | bool supportsRegOptional = false; |
3082 | |
3083 | if (IsContainableHWIntrinsicOp(node, op3, &supportsRegOptional)) |
3084 | { |
3085 | // 213 form: op1 = (op2 * op1) + [op3] |
3086 | MakeSrcContained(node, op3); |
3087 | } |
3088 | else if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
3089 | { |
3090 | // 132 form: op1 = (op1 * op3) + [op2] |
3091 | MakeSrcContained(node, op2); |
3092 | } |
3093 | else if (IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
3094 | { |
3095 | // Intrinsics with CopyUpperBits semantics cannot have op1 be contained |
3096 | |
3097 | if (!HWIntrinsicInfo::CopiesUpperBits(intrinsicId)) |
3098 | { |
3099 | // 231 form: op3 = (op2 * op3) + [op1] |
3100 | MakeSrcContained(node, op1); |
3101 | } |
3102 | } |
3103 | else |
3104 | { |
3105 | assert(supportsRegOptional); |
3106 | |
3107 | // TODO-XArch-CQ: Technically any one of the three operands can |
3108 | // be reg-optional. With a limitation on op1 where |
3109 | // it can only be so if CopyUpperBits is off. |
3110 | // https://github.com/dotnet/coreclr/issues/6361 |
3111 | |
3112 | // 213 form: op1 = (op2 * op1) + op3 |
3113 | op3->SetRegOptional(); |
3114 | } |
3115 | } |
3116 | else |
3117 | { |
3118 | bool supportsRegOptional = false; |
3119 | |
3120 | switch (intrinsicId) |
3121 | { |
3122 | case NI_SSE41_BlendVariable: |
3123 | case NI_AVX_BlendVariable: |
3124 | case NI_AVX2_BlendVariable: |
3125 | { |
3126 | if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
3127 | { |
3128 | MakeSrcContained(node, op2); |
3129 | } |
3130 | else if (supportsRegOptional) |
3131 | { |
3132 | op2->SetRegOptional(); |
3133 | } |
3134 | break; |
3135 | } |
3136 | |
3137 | case NI_BMI2_MultiplyNoFlags: |
3138 | case NI_BMI2_X64_MultiplyNoFlags: |
3139 | { |
3140 | if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
3141 | { |
3142 | MakeSrcContained(node, op2); |
3143 | } |
3144 | else if (IsContainableHWIntrinsicOp(node, op1, &supportsRegOptional)) |
3145 | { |
3146 | MakeSrcContained(node, op1); |
3147 | // MultiplyNoFlags is a Commutative operation, so swap the first two operands here |
3148 | // to make the containment checks in codegen significantly simpler |
3149 | *(originalArgList->pCurrent()) = op2; |
3150 | *(originalArgList->Rest()->pCurrent()) = op1; |
3151 | } |
3152 | else if (supportsRegOptional) |
3153 | { |
3154 | op2->SetRegOptional(); |
3155 | } |
3156 | break; |
3157 | } |
3158 | |
3159 | default: |
3160 | { |
3161 | unreached(); |
3162 | break; |
3163 | } |
3164 | } |
3165 | } |
3166 | } |
3167 | |
3168 | case HW_Category_IMM: |
3169 | { |
3170 | bool supportsRegOptional = false; |
3171 | |
3172 | switch (intrinsicId) |
3173 | { |
3174 | case NI_SSE_Shuffle: |
3175 | case NI_SSE2_Insert: |
3176 | case NI_SSE2_Shuffle: |
3177 | case NI_SSSE3_AlignRight: |
3178 | case NI_SSE41_Blend: |
3179 | case NI_SSE41_DotProduct: |
3180 | case NI_SSE41_Insert: |
3181 | case NI_SSE41_X64_Insert: |
3182 | case NI_SSE41_MultipleSumAbsoluteDifferences: |
3183 | case NI_AVX_Blend: |
3184 | case NI_AVX_Compare: |
3185 | case NI_AVX_CompareScalar: |
3186 | case NI_AVX_DotProduct: |
3187 | case NI_AVX_Permute2x128: |
3188 | case NI_AVX_Shuffle: |
3189 | case NI_AVX2_Blend: |
3190 | case NI_AVX2_MultipleSumAbsoluteDifferences: |
3191 | case NI_AVX2_Permute2x128: |
3192 | case NI_PCLMULQDQ_CarrylessMultiply: |
3193 | { |
3194 | if (IsContainableHWIntrinsicOp(node, op2, &supportsRegOptional)) |
3195 | { |
3196 | MakeSrcContained(node, op2); |
3197 | } |
3198 | else if (supportsRegOptional) |
3199 | { |
3200 | op2->SetRegOptional(); |
3201 | } |
3202 | break; |
3203 | } |
3204 | |
3205 | default: |
3206 | { |
3207 | break; |
3208 | } |
3209 | } |
3210 | |
3211 | break; |
3212 | } |
3213 | |
3214 | default: |
3215 | { |
3216 | unreached(); |
3217 | break; |
3218 | } |
3219 | } |
3220 | } |
3221 | else |
3222 | { |
3223 | unreached(); |
3224 | } |
3225 | |
3226 | if (HWIntrinsicInfo::lookupCategory(intrinsicId) == HW_Category_IMM) |
3227 | { |
3228 | GenTree* lastOp = HWIntrinsicInfo::lookupLastOp(node); |
3229 | assert(lastOp != nullptr); |
3230 | |
3231 | if (HWIntrinsicInfo::isImmOp(intrinsicId, lastOp) && lastOp->IsCnsIntOrI()) |
3232 | { |
3233 | MakeSrcContained(node, lastOp); |
3234 | } |
3235 | } |
3236 | } |
3237 | } |
3238 | #endif // FEATURE_HW_INTRINSICS |
3239 | |
3240 | //------------------------------------------------------------------------ |
3241 | // ContainCheckFloatBinary: determine whether the sources of a floating point binary node should be contained. |
3242 | // |
3243 | // Arguments: |
3244 | // node - pointer to the node |
3245 | // |
3246 | void Lowering::ContainCheckFloatBinary(GenTreeOp* node) |
3247 | { |
3248 | assert(node->OperIs(GT_ADD, GT_SUB, GT_MUL, GT_DIV) && varTypeIsFloating(node)); |
3249 | |
3250 | // overflow operations aren't supported on float/double types. |
3251 | assert(!node->gtOverflowEx()); |
3252 | |
3253 | GenTree* op1 = node->gtGetOp1(); |
3254 | GenTree* op2 = node->gtGetOp2(); |
3255 | |
3256 | // No implicit conversions at this stage as the expectation is that |
3257 | // everything is made explicit by adding casts. |
3258 | assert(op1->TypeGet() == op2->TypeGet()); |
3259 | |
3260 | bool isSafeToContainOp1 = true; |
3261 | bool isSafeToContainOp2 = true; |
3262 | |
3263 | if (op2->IsCnsNonZeroFltOrDbl()) |
3264 | { |
3265 | MakeSrcContained(node, op2); |
3266 | } |
3267 | else if (IsContainableMemoryOp(op2)) |
3268 | { |
3269 | isSafeToContainOp2 = IsSafeToContainMem(node, op2); |
3270 | if (isSafeToContainOp2) |
3271 | { |
3272 | MakeSrcContained(node, op2); |
3273 | } |
3274 | } |
3275 | |
3276 | if (!op2->isContained() && node->OperIsCommutative()) |
3277 | { |
3278 | // Though we have GT_ADD(op1=memOp, op2=non-memOp, we try to reorder the operands |
3279 | // as long as it is safe so that the following efficient code sequence is generated: |
3280 | // addss/sd targetReg, memOp (if op1Reg == targetReg) OR |
3281 | // movaps targetReg, op2Reg; addss/sd targetReg, [memOp] |
3282 | // |
3283 | // Instead of |
3284 | // movss op1Reg, [memOp]; addss/sd targetReg, Op2Reg (if op1Reg == targetReg) OR |
3285 | // movss op1Reg, [memOp]; movaps targetReg, op1Reg, addss/sd targetReg, Op2Reg |
3286 | |
3287 | if (op1->IsCnsNonZeroFltOrDbl()) |
3288 | { |
3289 | MakeSrcContained(node, op1); |
3290 | } |
3291 | else if (IsContainableMemoryOp(op1)) |
3292 | { |
3293 | isSafeToContainOp1 = IsSafeToContainMem(node, op1); |
3294 | if (isSafeToContainOp1) |
3295 | { |
3296 | MakeSrcContained(node, op1); |
3297 | } |
3298 | } |
3299 | } |
3300 | |
3301 | if (!op1->isContained() && !op2->isContained()) |
3302 | { |
3303 | // If there are no containable operands, we can make an operand reg optional. |
3304 | // IsSafeToContainMem is expensive so we call it at most once for each operand |
3305 | // in this method. If we already called IsSafeToContainMem, it must have returned false; |
3306 | // otherwise, the corresponding operand (op1 or op2) would be contained. |
3307 | isSafeToContainOp1 = isSafeToContainOp1 && IsSafeToContainMem(node, op1); |
3308 | isSafeToContainOp2 = isSafeToContainOp2 && IsSafeToContainMem(node, op2); |
3309 | SetRegOptionalForBinOp(node, isSafeToContainOp1, isSafeToContainOp2); |
3310 | } |
3311 | } |
3312 | |
3313 | #endif // _TARGET_XARCH_ |
3314 | |