1 //===-- AMDGPUTargetMachine.cpp - TargetMachine for hw codegen targets-----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 /// \file
10 /// The AMDGPU target machine contains all of the hardware specific
11 /// information  needed to emit code for SI+ GPUs.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "AMDGPUTargetMachine.h"
16 #include "AMDGPU.h"
17 #include "AMDGPUAliasAnalysis.h"
18 #include "AMDGPUExportClustering.h"
19 #include "AMDGPUMacroFusion.h"
20 #include "AMDGPUTargetObjectFile.h"
21 #include "AMDGPUTargetTransformInfo.h"
22 #include "GCNIterativeScheduler.h"
23 #include "GCNSchedStrategy.h"
24 #include "R600.h"
25 #include "R600TargetMachine.h"
26 #include "SIMachineFunctionInfo.h"
27 #include "SIMachineScheduler.h"
28 #include "TargetInfo/AMDGPUTargetInfo.h"
29 #include "llvm/Analysis/CGSCCPassManager.h"
30 #include "llvm/CodeGen/GlobalISel/IRTranslator.h"
31 #include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
32 #include "llvm/CodeGen/GlobalISel/Legalizer.h"
33 #include "llvm/CodeGen/GlobalISel/Localizer.h"
34 #include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
35 #include "llvm/CodeGen/MIRParser/MIParser.h"
36 #include "llvm/CodeGen/Passes.h"
37 #include "llvm/CodeGen/RegAllocRegistry.h"
38 #include "llvm/CodeGen/TargetPassConfig.h"
39 #include "llvm/IR/LegacyPassManager.h"
40 #include "llvm/IR/PassManager.h"
41 #include "llvm/InitializePasses.h"
42 #include "llvm/MC/TargetRegistry.h"
43 #include "llvm/Passes/PassBuilder.h"
44 #include "llvm/Transforms/IPO.h"
45 #include "llvm/Transforms/IPO/AlwaysInliner.h"
46 #include "llvm/Transforms/IPO/GlobalDCE.h"
47 #include "llvm/Transforms/IPO/Internalize.h"
48 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
49 #include "llvm/Transforms/Scalar.h"
50 #include "llvm/Transforms/Scalar/GVN.h"
51 #include "llvm/Transforms/Scalar/InferAddressSpaces.h"
52 #include "llvm/Transforms/Utils.h"
53 #include "llvm/Transforms/Utils/SimplifyLibCalls.h"
54 #include "llvm/Transforms/Vectorize.h"
55 
56 using namespace llvm;
57 
58 namespace {
59 class SGPRRegisterRegAlloc : public RegisterRegAllocBase<SGPRRegisterRegAlloc> {
60 public:
SGPRRegisterRegAlloc(const char * N,const char * D,FunctionPassCtor C)61   SGPRRegisterRegAlloc(const char *N, const char *D, FunctionPassCtor C)
62     : RegisterRegAllocBase(N, D, C) {}
63 };
64 
65 class VGPRRegisterRegAlloc : public RegisterRegAllocBase<VGPRRegisterRegAlloc> {
66 public:
VGPRRegisterRegAlloc(const char * N,const char * D,FunctionPassCtor C)67   VGPRRegisterRegAlloc(const char *N, const char *D, FunctionPassCtor C)
68     : RegisterRegAllocBase(N, D, C) {}
69 };
70 
onlyAllocateSGPRs(const TargetRegisterInfo & TRI,const TargetRegisterClass & RC)71 static bool onlyAllocateSGPRs(const TargetRegisterInfo &TRI,
72                               const TargetRegisterClass &RC) {
73   return static_cast<const SIRegisterInfo &>(TRI).isSGPRClass(&RC);
74 }
75 
onlyAllocateVGPRs(const TargetRegisterInfo & TRI,const TargetRegisterClass & RC)76 static bool onlyAllocateVGPRs(const TargetRegisterInfo &TRI,
77                               const TargetRegisterClass &RC) {
78   return !static_cast<const SIRegisterInfo &>(TRI).isSGPRClass(&RC);
79 }
80 
81 
82 /// -{sgpr|vgpr}-regalloc=... command line option.
useDefaultRegisterAllocator()83 static FunctionPass *useDefaultRegisterAllocator() { return nullptr; }
84 
85 /// A dummy default pass factory indicates whether the register allocator is
86 /// overridden on the command line.
87 static llvm::once_flag InitializeDefaultSGPRRegisterAllocatorFlag;
88 static llvm::once_flag InitializeDefaultVGPRRegisterAllocatorFlag;
89 
90 static SGPRRegisterRegAlloc
91 defaultSGPRRegAlloc("default",
92                     "pick SGPR register allocator based on -O option",
93                     useDefaultRegisterAllocator);
94 
95 static cl::opt<SGPRRegisterRegAlloc::FunctionPassCtor, false,
96                RegisterPassParser<SGPRRegisterRegAlloc>>
97 SGPRRegAlloc("sgpr-regalloc", cl::Hidden, cl::init(&useDefaultRegisterAllocator),
98              cl::desc("Register allocator to use for SGPRs"));
99 
100 static cl::opt<VGPRRegisterRegAlloc::FunctionPassCtor, false,
101                RegisterPassParser<VGPRRegisterRegAlloc>>
102 VGPRRegAlloc("vgpr-regalloc", cl::Hidden, cl::init(&useDefaultRegisterAllocator),
103              cl::desc("Register allocator to use for VGPRs"));
104 
105 
initializeDefaultSGPRRegisterAllocatorOnce()106 static void initializeDefaultSGPRRegisterAllocatorOnce() {
107   RegisterRegAlloc::FunctionPassCtor Ctor = SGPRRegisterRegAlloc::getDefault();
108 
109   if (!Ctor) {
110     Ctor = SGPRRegAlloc;
111     SGPRRegisterRegAlloc::setDefault(SGPRRegAlloc);
112   }
113 }
114 
initializeDefaultVGPRRegisterAllocatorOnce()115 static void initializeDefaultVGPRRegisterAllocatorOnce() {
116   RegisterRegAlloc::FunctionPassCtor Ctor = VGPRRegisterRegAlloc::getDefault();
117 
118   if (!Ctor) {
119     Ctor = VGPRRegAlloc;
120     VGPRRegisterRegAlloc::setDefault(VGPRRegAlloc);
121   }
122 }
123 
createBasicSGPRRegisterAllocator()124 static FunctionPass *createBasicSGPRRegisterAllocator() {
125   return createBasicRegisterAllocator(onlyAllocateSGPRs);
126 }
127 
createGreedySGPRRegisterAllocator()128 static FunctionPass *createGreedySGPRRegisterAllocator() {
129   return createGreedyRegisterAllocator(onlyAllocateSGPRs);
130 }
131 
createFastSGPRRegisterAllocator()132 static FunctionPass *createFastSGPRRegisterAllocator() {
133   return createFastRegisterAllocator(onlyAllocateSGPRs, false);
134 }
135 
createBasicVGPRRegisterAllocator()136 static FunctionPass *createBasicVGPRRegisterAllocator() {
137   return createBasicRegisterAllocator(onlyAllocateVGPRs);
138 }
139 
createGreedyVGPRRegisterAllocator()140 static FunctionPass *createGreedyVGPRRegisterAllocator() {
141   return createGreedyRegisterAllocator(onlyAllocateVGPRs);
142 }
143 
createFastVGPRRegisterAllocator()144 static FunctionPass *createFastVGPRRegisterAllocator() {
145   return createFastRegisterAllocator(onlyAllocateVGPRs, true);
146 }
147 
148 static SGPRRegisterRegAlloc basicRegAllocSGPR(
149   "basic", "basic register allocator", createBasicSGPRRegisterAllocator);
150 static SGPRRegisterRegAlloc greedyRegAllocSGPR(
151   "greedy", "greedy register allocator", createGreedySGPRRegisterAllocator);
152 
153 static SGPRRegisterRegAlloc fastRegAllocSGPR(
154   "fast", "fast register allocator", createFastSGPRRegisterAllocator);
155 
156 
157 static VGPRRegisterRegAlloc basicRegAllocVGPR(
158   "basic", "basic register allocator", createBasicVGPRRegisterAllocator);
159 static VGPRRegisterRegAlloc greedyRegAllocVGPR(
160   "greedy", "greedy register allocator", createGreedyVGPRRegisterAllocator);
161 
162 static VGPRRegisterRegAlloc fastRegAllocVGPR(
163   "fast", "fast register allocator", createFastVGPRRegisterAllocator);
164 }
165 
166 static cl::opt<bool> EnableSROA(
167   "amdgpu-sroa",
168   cl::desc("Run SROA after promote alloca pass"),
169   cl::ReallyHidden,
170   cl::init(true));
171 
172 static cl::opt<bool>
173 EnableEarlyIfConversion("amdgpu-early-ifcvt", cl::Hidden,
174                         cl::desc("Run early if-conversion"),
175                         cl::init(false));
176 
177 static cl::opt<bool>
178 OptExecMaskPreRA("amdgpu-opt-exec-mask-pre-ra", cl::Hidden,
179             cl::desc("Run pre-RA exec mask optimizations"),
180             cl::init(true));
181 
182 // Option to disable vectorizer for tests.
183 static cl::opt<bool> EnableLoadStoreVectorizer(
184   "amdgpu-load-store-vectorizer",
185   cl::desc("Enable load store vectorizer"),
186   cl::init(true),
187   cl::Hidden);
188 
189 // Option to control global loads scalarization
190 static cl::opt<bool> ScalarizeGlobal(
191   "amdgpu-scalarize-global-loads",
192   cl::desc("Enable global load scalarization"),
193   cl::init(true),
194   cl::Hidden);
195 
196 // Option to run internalize pass.
197 static cl::opt<bool> InternalizeSymbols(
198   "amdgpu-internalize-symbols",
199   cl::desc("Enable elimination of non-kernel functions and unused globals"),
200   cl::init(false),
201   cl::Hidden);
202 
203 // Option to inline all early.
204 static cl::opt<bool> EarlyInlineAll(
205   "amdgpu-early-inline-all",
206   cl::desc("Inline all functions early"),
207   cl::init(false),
208   cl::Hidden);
209 
210 static cl::opt<bool> EnableSDWAPeephole(
211   "amdgpu-sdwa-peephole",
212   cl::desc("Enable SDWA peepholer"),
213   cl::init(true));
214 
215 static cl::opt<bool> EnableDPPCombine(
216   "amdgpu-dpp-combine",
217   cl::desc("Enable DPP combiner"),
218   cl::init(true));
219 
220 // Enable address space based alias analysis
221 static cl::opt<bool> EnableAMDGPUAliasAnalysis("enable-amdgpu-aa", cl::Hidden,
222   cl::desc("Enable AMDGPU Alias Analysis"),
223   cl::init(true));
224 
225 // Option to run late CFG structurizer
226 static cl::opt<bool, true> LateCFGStructurize(
227   "amdgpu-late-structurize",
228   cl::desc("Enable late CFG structurization"),
229   cl::location(AMDGPUTargetMachine::EnableLateStructurizeCFG),
230   cl::Hidden);
231 
232 static cl::opt<bool, true> EnableAMDGPUFixedFunctionABIOpt(
233   "amdgpu-fixed-function-abi",
234   cl::desc("Enable all implicit function arguments"),
235   cl::location(AMDGPUTargetMachine::EnableFixedFunctionABI),
236   cl::init(false),
237   cl::Hidden);
238 
239 // Enable lib calls simplifications
240 static cl::opt<bool> EnableLibCallSimplify(
241   "amdgpu-simplify-libcall",
242   cl::desc("Enable amdgpu library simplifications"),
243   cl::init(true),
244   cl::Hidden);
245 
246 static cl::opt<bool> EnableLowerKernelArguments(
247   "amdgpu-ir-lower-kernel-arguments",
248   cl::desc("Lower kernel argument loads in IR pass"),
249   cl::init(true),
250   cl::Hidden);
251 
252 static cl::opt<bool> EnableRegReassign(
253   "amdgpu-reassign-regs",
254   cl::desc("Enable register reassign optimizations on gfx10+"),
255   cl::init(true),
256   cl::Hidden);
257 
258 static cl::opt<bool> OptVGPRLiveRange(
259     "amdgpu-opt-vgpr-liverange",
260     cl::desc("Enable VGPR liverange optimizations for if-else structure"),
261     cl::init(true), cl::Hidden);
262 
263 // Enable atomic optimization
264 static cl::opt<bool> EnableAtomicOptimizations(
265   "amdgpu-atomic-optimizations",
266   cl::desc("Enable atomic optimizations"),
267   cl::init(false),
268   cl::Hidden);
269 
270 // Enable Mode register optimization
271 static cl::opt<bool> EnableSIModeRegisterPass(
272   "amdgpu-mode-register",
273   cl::desc("Enable mode register pass"),
274   cl::init(true),
275   cl::Hidden);
276 
277 // Option is used in lit tests to prevent deadcoding of patterns inspected.
278 static cl::opt<bool>
279 EnableDCEInRA("amdgpu-dce-in-ra",
280     cl::init(true), cl::Hidden,
281     cl::desc("Enable machine DCE inside regalloc"));
282 
283 static cl::opt<bool> EnableScalarIRPasses(
284   "amdgpu-scalar-ir-passes",
285   cl::desc("Enable scalar IR passes"),
286   cl::init(true),
287   cl::Hidden);
288 
289 static cl::opt<bool> EnableStructurizerWorkarounds(
290     "amdgpu-enable-structurizer-workarounds",
291     cl::desc("Enable workarounds for the StructurizeCFG pass"), cl::init(true),
292     cl::Hidden);
293 
294 static cl::opt<bool> EnableLDSReplaceWithPointer(
295     "amdgpu-enable-lds-replace-with-pointer",
296     cl::desc("Enable LDS replace with pointer pass"), cl::init(false),
297     cl::Hidden);
298 
299 static cl::opt<bool, true> EnableLowerModuleLDS(
300     "amdgpu-enable-lower-module-lds", cl::desc("Enable lower module lds pass"),
301     cl::location(AMDGPUTargetMachine::EnableLowerModuleLDS), cl::init(true),
302     cl::Hidden);
303 
304 static cl::opt<bool> EnablePreRAOptimizations(
305     "amdgpu-enable-pre-ra-optimizations",
306     cl::desc("Enable Pre-RA optimizations pass"), cl::init(true),
307     cl::Hidden);
308 
LLVMInitializeAMDGPUTarget()309 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAMDGPUTarget() {
310   // Register the target
311   RegisterTargetMachine<R600TargetMachine> X(getTheAMDGPUTarget());
312   RegisterTargetMachine<GCNTargetMachine> Y(getTheGCNTarget());
313 
314   PassRegistry *PR = PassRegistry::getPassRegistry();
315   initializeR600ClauseMergePassPass(*PR);
316   initializeR600ControlFlowFinalizerPass(*PR);
317   initializeR600PacketizerPass(*PR);
318   initializeR600ExpandSpecialInstrsPassPass(*PR);
319   initializeR600VectorRegMergerPass(*PR);
320   initializeGlobalISel(*PR);
321   initializeAMDGPUDAGToDAGISelPass(*PR);
322   initializeGCNDPPCombinePass(*PR);
323   initializeSILowerI1CopiesPass(*PR);
324   initializeSILowerSGPRSpillsPass(*PR);
325   initializeSIFixSGPRCopiesPass(*PR);
326   initializeSIFixVGPRCopiesPass(*PR);
327   initializeSIFoldOperandsPass(*PR);
328   initializeSIPeepholeSDWAPass(*PR);
329   initializeSIShrinkInstructionsPass(*PR);
330   initializeSIOptimizeExecMaskingPreRAPass(*PR);
331   initializeSIOptimizeVGPRLiveRangePass(*PR);
332   initializeSILoadStoreOptimizerPass(*PR);
333   initializeAMDGPUFixFunctionBitcastsPass(*PR);
334   initializeAMDGPUCtorDtorLoweringPass(*PR);
335   initializeAMDGPUAlwaysInlinePass(*PR);
336   initializeAMDGPUAttributorPass(*PR);
337   initializeAMDGPUAnnotateKernelFeaturesPass(*PR);
338   initializeAMDGPUAnnotateUniformValuesPass(*PR);
339   initializeAMDGPUArgumentUsageInfoPass(*PR);
340   initializeAMDGPUAtomicOptimizerPass(*PR);
341   initializeAMDGPULowerKernelArgumentsPass(*PR);
342   initializeAMDGPULowerKernelAttributesPass(*PR);
343   initializeAMDGPULowerIntrinsicsPass(*PR);
344   initializeAMDGPUOpenCLEnqueuedBlockLoweringPass(*PR);
345   initializeAMDGPUPostLegalizerCombinerPass(*PR);
346   initializeAMDGPUPreLegalizerCombinerPass(*PR);
347   initializeAMDGPURegBankCombinerPass(*PR);
348   initializeAMDGPUPromoteAllocaPass(*PR);
349   initializeAMDGPUPromoteAllocaToVectorPass(*PR);
350   initializeAMDGPUCodeGenPreparePass(*PR);
351   initializeAMDGPULateCodeGenPreparePass(*PR);
352   initializeAMDGPUPropagateAttributesEarlyPass(*PR);
353   initializeAMDGPUPropagateAttributesLatePass(*PR);
354   initializeAMDGPUReplaceLDSUseWithPointerPass(*PR);
355   initializeAMDGPULowerModuleLDSPass(*PR);
356   initializeAMDGPURewriteOutArgumentsPass(*PR);
357   initializeAMDGPUUnifyMetadataPass(*PR);
358   initializeSIAnnotateControlFlowPass(*PR);
359   initializeSIInsertHardClausesPass(*PR);
360   initializeSIInsertWaitcntsPass(*PR);
361   initializeSIModeRegisterPass(*PR);
362   initializeSIWholeQuadModePass(*PR);
363   initializeSILowerControlFlowPass(*PR);
364   initializeSIPreEmitPeepholePass(*PR);
365   initializeSILateBranchLoweringPass(*PR);
366   initializeSIMemoryLegalizerPass(*PR);
367   initializeSIOptimizeExecMaskingPass(*PR);
368   initializeSIPreAllocateWWMRegsPass(*PR);
369   initializeSIFormMemoryClausesPass(*PR);
370   initializeSIPostRABundlerPass(*PR);
371   initializeAMDGPUUnifyDivergentExitNodesPass(*PR);
372   initializeAMDGPUAAWrapperPassPass(*PR);
373   initializeAMDGPUExternalAAWrapperPass(*PR);
374   initializeAMDGPUUseNativeCallsPass(*PR);
375   initializeAMDGPUSimplifyLibCallsPass(*PR);
376   initializeAMDGPUPrintfRuntimeBindingPass(*PR);
377   initializeAMDGPUResourceUsageAnalysisPass(*PR);
378   initializeGCNNSAReassignPass(*PR);
379   initializeGCNPreRAOptimizationsPass(*PR);
380 }
381 
createTLOF(const Triple & TT)382 static std::unique_ptr<TargetLoweringObjectFile> createTLOF(const Triple &TT) {
383   return std::make_unique<AMDGPUTargetObjectFile>();
384 }
385 
createSIMachineScheduler(MachineSchedContext * C)386 static ScheduleDAGInstrs *createSIMachineScheduler(MachineSchedContext *C) {
387   return new SIScheduleDAGMI(C);
388 }
389 
390 static ScheduleDAGInstrs *
createGCNMaxOccupancyMachineScheduler(MachineSchedContext * C)391 createGCNMaxOccupancyMachineScheduler(MachineSchedContext *C) {
392   ScheduleDAGMILive *DAG =
393     new GCNScheduleDAGMILive(C, std::make_unique<GCNMaxOccupancySchedStrategy>(C));
394   DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
395   DAG->addMutation(createAMDGPUMacroFusionDAGMutation());
396   DAG->addMutation(createAMDGPUExportClusteringDAGMutation());
397   return DAG;
398 }
399 
400 static ScheduleDAGInstrs *
createIterativeGCNMaxOccupancyMachineScheduler(MachineSchedContext * C)401 createIterativeGCNMaxOccupancyMachineScheduler(MachineSchedContext *C) {
402   auto DAG = new GCNIterativeScheduler(C,
403     GCNIterativeScheduler::SCHEDULE_LEGACYMAXOCCUPANCY);
404   DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
405   return DAG;
406 }
407 
createMinRegScheduler(MachineSchedContext * C)408 static ScheduleDAGInstrs *createMinRegScheduler(MachineSchedContext *C) {
409   return new GCNIterativeScheduler(C,
410     GCNIterativeScheduler::SCHEDULE_MINREGFORCED);
411 }
412 
413 static ScheduleDAGInstrs *
createIterativeILPMachineScheduler(MachineSchedContext * C)414 createIterativeILPMachineScheduler(MachineSchedContext *C) {
415   auto DAG = new GCNIterativeScheduler(C,
416     GCNIterativeScheduler::SCHEDULE_ILP);
417   DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
418   DAG->addMutation(createAMDGPUMacroFusionDAGMutation());
419   return DAG;
420 }
421 
422 static MachineSchedRegistry
423 SISchedRegistry("si", "Run SI's custom scheduler",
424                 createSIMachineScheduler);
425 
426 static MachineSchedRegistry
427 GCNMaxOccupancySchedRegistry("gcn-max-occupancy",
428                              "Run GCN scheduler to maximize occupancy",
429                              createGCNMaxOccupancyMachineScheduler);
430 
431 static MachineSchedRegistry
432 IterativeGCNMaxOccupancySchedRegistry("gcn-max-occupancy-experimental",
433   "Run GCN scheduler to maximize occupancy (experimental)",
434   createIterativeGCNMaxOccupancyMachineScheduler);
435 
436 static MachineSchedRegistry
437 GCNMinRegSchedRegistry("gcn-minreg",
438   "Run GCN iterative scheduler for minimal register usage (experimental)",
439   createMinRegScheduler);
440 
441 static MachineSchedRegistry
442 GCNILPSchedRegistry("gcn-ilp",
443   "Run GCN iterative scheduler for ILP scheduling (experimental)",
444   createIterativeILPMachineScheduler);
445 
computeDataLayout(const Triple & TT)446 static StringRef computeDataLayout(const Triple &TT) {
447   if (TT.getArch() == Triple::r600) {
448     // 32-bit pointers.
449     return "e-p:32:32-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
450            "-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-S32-A5-G1";
451   }
452 
453   // 32-bit private, local, and region pointers. 64-bit global, constant and
454   // flat, non-integral buffer fat pointers.
455   return "e-p:64:64-p1:64:64-p2:32:32-p3:32:32-p4:64:64-p5:32:32-p6:32:32"
456          "-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128"
457          "-v192:256-v256:256-v512:512-v1024:1024-v2048:2048-n32:64-S32-A5-G1"
458          "-ni:7";
459 }
460 
461 LLVM_READNONE
getGPUOrDefault(const Triple & TT,StringRef GPU)462 static StringRef getGPUOrDefault(const Triple &TT, StringRef GPU) {
463   if (!GPU.empty())
464     return GPU;
465 
466   // Need to default to a target with flat support for HSA.
467   if (TT.getArch() == Triple::amdgcn)
468     return TT.getOS() == Triple::AMDHSA ? "generic-hsa" : "generic";
469 
470   return "r600";
471 }
472 
getEffectiveRelocModel(Optional<Reloc::Model> RM)473 static Reloc::Model getEffectiveRelocModel(Optional<Reloc::Model> RM) {
474   // The AMDGPU toolchain only supports generating shared objects, so we
475   // must always use PIC.
476   return Reloc::PIC_;
477 }
478 
AMDGPUTargetMachine(const Target & T,const Triple & TT,StringRef CPU,StringRef FS,TargetOptions Options,Optional<Reloc::Model> RM,Optional<CodeModel::Model> CM,CodeGenOpt::Level OptLevel)479 AMDGPUTargetMachine::AMDGPUTargetMachine(const Target &T, const Triple &TT,
480                                          StringRef CPU, StringRef FS,
481                                          TargetOptions Options,
482                                          Optional<Reloc::Model> RM,
483                                          Optional<CodeModel::Model> CM,
484                                          CodeGenOpt::Level OptLevel)
485     : LLVMTargetMachine(T, computeDataLayout(TT), TT, getGPUOrDefault(TT, CPU),
486                         FS, Options, getEffectiveRelocModel(RM),
487                         getEffectiveCodeModel(CM, CodeModel::Small), OptLevel),
488       TLOF(createTLOF(getTargetTriple())) {
489   initAsmInfo();
490   if (TT.getArch() == Triple::amdgcn) {
491     if (getMCSubtargetInfo()->checkFeatures("+wavefrontsize64"))
492       MRI.reset(llvm::createGCNMCRegisterInfo(AMDGPUDwarfFlavour::Wave64));
493     else if (getMCSubtargetInfo()->checkFeatures("+wavefrontsize32"))
494       MRI.reset(llvm::createGCNMCRegisterInfo(AMDGPUDwarfFlavour::Wave32));
495   }
496 }
497 
498 bool AMDGPUTargetMachine::EnableLateStructurizeCFG = false;
499 bool AMDGPUTargetMachine::EnableFunctionCalls = false;
500 bool AMDGPUTargetMachine::EnableFixedFunctionABI = false;
501 bool AMDGPUTargetMachine::EnableLowerModuleLDS = true;
502 
503 AMDGPUTargetMachine::~AMDGPUTargetMachine() = default;
504 
getGPUName(const Function & F) const505 StringRef AMDGPUTargetMachine::getGPUName(const Function &F) const {
506   Attribute GPUAttr = F.getFnAttribute("target-cpu");
507   return GPUAttr.isValid() ? GPUAttr.getValueAsString() : getTargetCPU();
508 }
509 
getFeatureString(const Function & F) const510 StringRef AMDGPUTargetMachine::getFeatureString(const Function &F) const {
511   Attribute FSAttr = F.getFnAttribute("target-features");
512 
513   return FSAttr.isValid() ? FSAttr.getValueAsString()
514                           : getTargetFeatureString();
515 }
516 
517 /// Predicate for Internalize pass.
mustPreserveGV(const GlobalValue & GV)518 static bool mustPreserveGV(const GlobalValue &GV) {
519   if (const Function *F = dyn_cast<Function>(&GV))
520     return F->isDeclaration() || F->getName().startswith("__asan_") ||
521            F->getName().startswith("__sanitizer_") ||
522            AMDGPU::isEntryFunctionCC(F->getCallingConv());
523 
524   GV.removeDeadConstantUsers();
525   return !GV.use_empty();
526 }
527 
adjustPassManager(PassManagerBuilder & Builder)528 void AMDGPUTargetMachine::adjustPassManager(PassManagerBuilder &Builder) {
529   Builder.DivergentTarget = true;
530 
531   bool EnableOpt = getOptLevel() > CodeGenOpt::None;
532   bool Internalize = InternalizeSymbols;
533   bool EarlyInline = EarlyInlineAll && EnableOpt && !EnableFunctionCalls;
534   bool AMDGPUAA = EnableAMDGPUAliasAnalysis && EnableOpt;
535   bool LibCallSimplify = EnableLibCallSimplify && EnableOpt;
536 
537   if (EnableFunctionCalls) {
538     delete Builder.Inliner;
539     Builder.Inliner = createFunctionInliningPass();
540   }
541 
542   Builder.addExtension(
543     PassManagerBuilder::EP_ModuleOptimizerEarly,
544     [Internalize, EarlyInline, AMDGPUAA, this](const PassManagerBuilder &,
545                                                legacy::PassManagerBase &PM) {
546       if (AMDGPUAA) {
547         PM.add(createAMDGPUAAWrapperPass());
548         PM.add(createAMDGPUExternalAAWrapperPass());
549       }
550       PM.add(createAMDGPUUnifyMetadataPass());
551       PM.add(createAMDGPUPrintfRuntimeBinding());
552       if (Internalize)
553         PM.add(createInternalizePass(mustPreserveGV));
554       PM.add(createAMDGPUPropagateAttributesLatePass(this));
555       if (Internalize)
556         PM.add(createGlobalDCEPass());
557       if (EarlyInline)
558         PM.add(createAMDGPUAlwaysInlinePass(false));
559   });
560 
561   Builder.addExtension(
562     PassManagerBuilder::EP_EarlyAsPossible,
563     [AMDGPUAA, LibCallSimplify, this](const PassManagerBuilder &,
564                                       legacy::PassManagerBase &PM) {
565       if (AMDGPUAA) {
566         PM.add(createAMDGPUAAWrapperPass());
567         PM.add(createAMDGPUExternalAAWrapperPass());
568       }
569       PM.add(llvm::createAMDGPUPropagateAttributesEarlyPass(this));
570       PM.add(llvm::createAMDGPUUseNativeCallsPass());
571       if (LibCallSimplify)
572         PM.add(llvm::createAMDGPUSimplifyLibCallsPass(this));
573   });
574 
575   Builder.addExtension(
576     PassManagerBuilder::EP_CGSCCOptimizerLate,
577     [EnableOpt](const PassManagerBuilder &, legacy::PassManagerBase &PM) {
578       // Add infer address spaces pass to the opt pipeline after inlining
579       // but before SROA to increase SROA opportunities.
580       PM.add(createInferAddressSpacesPass());
581 
582       // This should run after inlining to have any chance of doing anything,
583       // and before other cleanup optimizations.
584       PM.add(createAMDGPULowerKernelAttributesPass());
585 
586       // Promote alloca to vector before SROA and loop unroll. If we manage
587       // to eliminate allocas before unroll we may choose to unroll less.
588       if (EnableOpt)
589         PM.add(createAMDGPUPromoteAllocaToVector());
590   });
591 }
592 
registerDefaultAliasAnalyses(AAManager & AAM)593 void AMDGPUTargetMachine::registerDefaultAliasAnalyses(AAManager &AAM) {
594   AAM.registerFunctionAnalysis<AMDGPUAA>();
595 }
596 
registerPassBuilderCallbacks(PassBuilder & PB)597 void AMDGPUTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
598   PB.registerPipelineParsingCallback(
599       [this](StringRef PassName, ModulePassManager &PM,
600              ArrayRef<PassBuilder::PipelineElement>) {
601         if (PassName == "amdgpu-propagate-attributes-late") {
602           PM.addPass(AMDGPUPropagateAttributesLatePass(*this));
603           return true;
604         }
605         if (PassName == "amdgpu-unify-metadata") {
606           PM.addPass(AMDGPUUnifyMetadataPass());
607           return true;
608         }
609         if (PassName == "amdgpu-printf-runtime-binding") {
610           PM.addPass(AMDGPUPrintfRuntimeBindingPass());
611           return true;
612         }
613         if (PassName == "amdgpu-always-inline") {
614           PM.addPass(AMDGPUAlwaysInlinePass());
615           return true;
616         }
617         if (PassName == "amdgpu-replace-lds-use-with-pointer") {
618           PM.addPass(AMDGPUReplaceLDSUseWithPointerPass());
619           return true;
620         }
621         if (PassName == "amdgpu-lower-module-lds") {
622           PM.addPass(AMDGPULowerModuleLDSPass());
623           return true;
624         }
625         return false;
626       });
627   PB.registerPipelineParsingCallback(
628       [this](StringRef PassName, FunctionPassManager &PM,
629              ArrayRef<PassBuilder::PipelineElement>) {
630         if (PassName == "amdgpu-simplifylib") {
631           PM.addPass(AMDGPUSimplifyLibCallsPass(*this));
632           return true;
633         }
634         if (PassName == "amdgpu-usenative") {
635           PM.addPass(AMDGPUUseNativeCallsPass());
636           return true;
637         }
638         if (PassName == "amdgpu-promote-alloca") {
639           PM.addPass(AMDGPUPromoteAllocaPass(*this));
640           return true;
641         }
642         if (PassName == "amdgpu-promote-alloca-to-vector") {
643           PM.addPass(AMDGPUPromoteAllocaToVectorPass(*this));
644           return true;
645         }
646         if (PassName == "amdgpu-lower-kernel-attributes") {
647           PM.addPass(AMDGPULowerKernelAttributesPass());
648           return true;
649         }
650         if (PassName == "amdgpu-propagate-attributes-early") {
651           PM.addPass(AMDGPUPropagateAttributesEarlyPass(*this));
652           return true;
653         }
654         return false;
655       });
656 
657   PB.registerAnalysisRegistrationCallback([](FunctionAnalysisManager &FAM) {
658     FAM.registerPass([&] { return AMDGPUAA(); });
659   });
660 
661   PB.registerParseAACallback([](StringRef AAName, AAManager &AAM) {
662     if (AAName == "amdgpu-aa") {
663       AAM.registerFunctionAnalysis<AMDGPUAA>();
664       return true;
665     }
666     return false;
667   });
668 
669   PB.registerPipelineStartEPCallback(
670       [this](ModulePassManager &PM, OptimizationLevel Level) {
671         FunctionPassManager FPM;
672         FPM.addPass(AMDGPUPropagateAttributesEarlyPass(*this));
673         FPM.addPass(AMDGPUUseNativeCallsPass());
674         if (EnableLibCallSimplify && Level != OptimizationLevel::O0)
675           FPM.addPass(AMDGPUSimplifyLibCallsPass(*this));
676         PM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
677       });
678 
679   PB.registerPipelineEarlySimplificationEPCallback(
680       [this](ModulePassManager &PM, OptimizationLevel Level) {
681         if (Level == OptimizationLevel::O0)
682           return;
683 
684         PM.addPass(AMDGPUUnifyMetadataPass());
685         PM.addPass(AMDGPUPrintfRuntimeBindingPass());
686 
687         if (InternalizeSymbols) {
688           PM.addPass(InternalizePass(mustPreserveGV));
689         }
690         PM.addPass(AMDGPUPropagateAttributesLatePass(*this));
691         if (InternalizeSymbols) {
692           PM.addPass(GlobalDCEPass());
693         }
694         if (EarlyInlineAll && !EnableFunctionCalls)
695           PM.addPass(AMDGPUAlwaysInlinePass());
696       });
697 
698   PB.registerCGSCCOptimizerLateEPCallback(
699       [this](CGSCCPassManager &PM, OptimizationLevel Level) {
700         if (Level == OptimizationLevel::O0)
701           return;
702 
703         FunctionPassManager FPM;
704 
705         // Add infer address spaces pass to the opt pipeline after inlining
706         // but before SROA to increase SROA opportunities.
707         FPM.addPass(InferAddressSpacesPass());
708 
709         // This should run after inlining to have any chance of doing
710         // anything, and before other cleanup optimizations.
711         FPM.addPass(AMDGPULowerKernelAttributesPass());
712 
713         if (Level != OptimizationLevel::O0) {
714           // Promote alloca to vector before SROA and loop unroll. If we
715           // manage to eliminate allocas before unroll we may choose to unroll
716           // less.
717           FPM.addPass(AMDGPUPromoteAllocaToVectorPass(*this));
718         }
719 
720         PM.addPass(createCGSCCToFunctionPassAdaptor(std::move(FPM)));
721       });
722 }
723 
getNullPointerValue(unsigned AddrSpace)724 int64_t AMDGPUTargetMachine::getNullPointerValue(unsigned AddrSpace) {
725   return (AddrSpace == AMDGPUAS::LOCAL_ADDRESS ||
726           AddrSpace == AMDGPUAS::PRIVATE_ADDRESS ||
727           AddrSpace == AMDGPUAS::REGION_ADDRESS)
728              ? -1
729              : 0;
730 }
731 
isNoopAddrSpaceCast(unsigned SrcAS,unsigned DestAS) const732 bool AMDGPUTargetMachine::isNoopAddrSpaceCast(unsigned SrcAS,
733                                               unsigned DestAS) const {
734   return AMDGPU::isFlatGlobalAddrSpace(SrcAS) &&
735          AMDGPU::isFlatGlobalAddrSpace(DestAS);
736 }
737 
getAssumedAddrSpace(const Value * V) const738 unsigned AMDGPUTargetMachine::getAssumedAddrSpace(const Value *V) const {
739   const auto *LD = dyn_cast<LoadInst>(V);
740   if (!LD)
741     return AMDGPUAS::UNKNOWN_ADDRESS_SPACE;
742 
743   // It must be a generic pointer loaded.
744   assert(V->getType()->isPointerTy() &&
745          V->getType()->getPointerAddressSpace() == AMDGPUAS::FLAT_ADDRESS);
746 
747   const auto *Ptr = LD->getPointerOperand();
748   if (Ptr->getType()->getPointerAddressSpace() != AMDGPUAS::CONSTANT_ADDRESS)
749     return AMDGPUAS::UNKNOWN_ADDRESS_SPACE;
750   // For a generic pointer loaded from the constant memory, it could be assumed
751   // as a global pointer since the constant memory is only populated on the
752   // host side. As implied by the offload programming model, only global
753   // pointers could be referenced on the host side.
754   return AMDGPUAS::GLOBAL_ADDRESS;
755 }
756 
757 //===----------------------------------------------------------------------===//
758 // GCN Target Machine (SI+)
759 //===----------------------------------------------------------------------===//
760 
GCNTargetMachine(const Target & T,const Triple & TT,StringRef CPU,StringRef FS,TargetOptions Options,Optional<Reloc::Model> RM,Optional<CodeModel::Model> CM,CodeGenOpt::Level OL,bool JIT)761 GCNTargetMachine::GCNTargetMachine(const Target &T, const Triple &TT,
762                                    StringRef CPU, StringRef FS,
763                                    TargetOptions Options,
764                                    Optional<Reloc::Model> RM,
765                                    Optional<CodeModel::Model> CM,
766                                    CodeGenOpt::Level OL, bool JIT)
767     : AMDGPUTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL) {}
768 
769 const TargetSubtargetInfo *
getSubtargetImpl(const Function & F) const770 GCNTargetMachine::getSubtargetImpl(const Function &F) const {
771   StringRef GPU = getGPUName(F);
772   StringRef FS = getFeatureString(F);
773 
774   SmallString<128> SubtargetKey(GPU);
775   SubtargetKey.append(FS);
776 
777   auto &I = SubtargetMap[SubtargetKey];
778   if (!I) {
779     // This needs to be done before we create a new subtarget since any
780     // creation will depend on the TM and the code generation flags on the
781     // function that reside in TargetOptions.
782     resetTargetOptions(F);
783     I = std::make_unique<GCNSubtarget>(TargetTriple, GPU, FS, *this);
784   }
785 
786   I->setScalarizeGlobalBehavior(ScalarizeGlobal);
787 
788   return I.get();
789 }
790 
791 TargetTransformInfo
getTargetTransformInfo(const Function & F)792 GCNTargetMachine::getTargetTransformInfo(const Function &F) {
793   return TargetTransformInfo(GCNTTIImpl(this, F));
794 }
795 
796 //===----------------------------------------------------------------------===//
797 // AMDGPU Pass Setup
798 //===----------------------------------------------------------------------===//
799 
getCSEConfig() const800 std::unique_ptr<CSEConfigBase> llvm::AMDGPUPassConfig::getCSEConfig() const {
801   return getStandardCSEConfigForOpt(TM->getOptLevel());
802 }
803 
804 namespace {
805 
806 class GCNPassConfig final : public AMDGPUPassConfig {
807 public:
GCNPassConfig(LLVMTargetMachine & TM,PassManagerBase & PM)808   GCNPassConfig(LLVMTargetMachine &TM, PassManagerBase &PM)
809     : AMDGPUPassConfig(TM, PM) {
810     // It is necessary to know the register usage of the entire call graph.  We
811     // allow calls without EnableAMDGPUFunctionCalls if they are marked
812     // noinline, so this is always required.
813     setRequiresCodeGenSCCOrder(true);
814     substitutePass(&PostRASchedulerID, &PostMachineSchedulerID);
815   }
816 
getGCNTargetMachine() const817   GCNTargetMachine &getGCNTargetMachine() const {
818     return getTM<GCNTargetMachine>();
819   }
820 
821   ScheduleDAGInstrs *
822   createMachineScheduler(MachineSchedContext *C) const override;
823 
824   ScheduleDAGInstrs *
createPostMachineScheduler(MachineSchedContext * C) const825   createPostMachineScheduler(MachineSchedContext *C) const override {
826     ScheduleDAGMI *DAG = createGenericSchedPostRA(C);
827     const GCNSubtarget &ST = C->MF->getSubtarget<GCNSubtarget>();
828     DAG->addMutation(ST.createFillMFMAShadowMutation(DAG->TII));
829     return DAG;
830   }
831 
832   bool addPreISel() override;
833   void addMachineSSAOptimization() override;
834   bool addILPOpts() override;
835   bool addInstSelector() override;
836   bool addIRTranslator() override;
837   void addPreLegalizeMachineIR() override;
838   bool addLegalizeMachineIR() override;
839   void addPreRegBankSelect() override;
840   bool addRegBankSelect() override;
841   void addPreGlobalInstructionSelect() override;
842   bool addGlobalInstructionSelect() override;
843   void addFastRegAlloc() override;
844   void addOptimizedRegAlloc() override;
845 
846   FunctionPass *createSGPRAllocPass(bool Optimized);
847   FunctionPass *createVGPRAllocPass(bool Optimized);
848   FunctionPass *createRegAllocPass(bool Optimized) override;
849 
850   bool addRegAssignAndRewriteFast() override;
851   bool addRegAssignAndRewriteOptimized() override;
852 
853   void addPreRegAlloc() override;
854   bool addPreRewrite() override;
855   void addPostRegAlloc() override;
856   void addPreSched2() override;
857   void addPreEmitPass() override;
858 };
859 
860 } // end anonymous namespace
861 
AMDGPUPassConfig(LLVMTargetMachine & TM,PassManagerBase & PM)862 AMDGPUPassConfig::AMDGPUPassConfig(LLVMTargetMachine &TM, PassManagerBase &PM)
863     : TargetPassConfig(TM, PM) {
864   // Exceptions and StackMaps are not supported, so these passes will never do
865   // anything.
866   disablePass(&StackMapLivenessID);
867   disablePass(&FuncletLayoutID);
868   // Garbage collection is not supported.
869   disablePass(&GCLoweringID);
870   disablePass(&ShadowStackGCLoweringID);
871 }
872 
addEarlyCSEOrGVNPass()873 void AMDGPUPassConfig::addEarlyCSEOrGVNPass() {
874   if (getOptLevel() == CodeGenOpt::Aggressive)
875     addPass(createGVNPass());
876   else
877     addPass(createEarlyCSEPass());
878 }
879 
addStraightLineScalarOptimizationPasses()880 void AMDGPUPassConfig::addStraightLineScalarOptimizationPasses() {
881   addPass(createLICMPass());
882   addPass(createSeparateConstOffsetFromGEPPass());
883   addPass(createSpeculativeExecutionPass());
884   // ReassociateGEPs exposes more opportunities for SLSR. See
885   // the example in reassociate-geps-and-slsr.ll.
886   addPass(createStraightLineStrengthReducePass());
887   // SeparateConstOffsetFromGEP and SLSR creates common expressions which GVN or
888   // EarlyCSE can reuse.
889   addEarlyCSEOrGVNPass();
890   // Run NaryReassociate after EarlyCSE/GVN to be more effective.
891   addPass(createNaryReassociatePass());
892   // NaryReassociate on GEPs creates redundant common expressions, so run
893   // EarlyCSE after it.
894   addPass(createEarlyCSEPass());
895 }
896 
addIRPasses()897 void AMDGPUPassConfig::addIRPasses() {
898   const AMDGPUTargetMachine &TM = getAMDGPUTargetMachine();
899 
900   // There is no reason to run these.
901   disablePass(&StackMapLivenessID);
902   disablePass(&FuncletLayoutID);
903   disablePass(&PatchableFunctionID);
904 
905   addPass(createAMDGPUPrintfRuntimeBinding());
906   addPass(createAMDGPUCtorDtorLoweringPass());
907 
908   // This must occur before inlining, as the inliner will not look through
909   // bitcast calls.
910   addPass(createAMDGPUFixFunctionBitcastsPass());
911 
912   // A call to propagate attributes pass in the backend in case opt was not run.
913   addPass(createAMDGPUPropagateAttributesEarlyPass(&TM));
914 
915   addPass(createAMDGPULowerIntrinsicsPass());
916 
917   // Function calls are not supported, so make sure we inline everything.
918   addPass(createAMDGPUAlwaysInlinePass());
919   addPass(createAlwaysInlinerLegacyPass());
920   // We need to add the barrier noop pass, otherwise adding the function
921   // inlining pass will cause all of the PassConfigs passes to be run
922   // one function at a time, which means if we have a nodule with two
923   // functions, then we will generate code for the first function
924   // without ever running any passes on the second.
925   addPass(createBarrierNoopPass());
926 
927   // Handle uses of OpenCL image2d_t, image3d_t and sampler_t arguments.
928   if (TM.getTargetTriple().getArch() == Triple::r600)
929     addPass(createR600OpenCLImageTypeLoweringPass());
930 
931   // Replace OpenCL enqueued block function pointers with global variables.
932   addPass(createAMDGPUOpenCLEnqueuedBlockLoweringPass());
933 
934   // Can increase LDS used by kernel so runs before PromoteAlloca
935   if (EnableLowerModuleLDS) {
936     // The pass "amdgpu-replace-lds-use-with-pointer" need to be run before the
937     // pass "amdgpu-lower-module-lds", and also it required to be run only if
938     // "amdgpu-lower-module-lds" pass is enabled.
939     if (EnableLDSReplaceWithPointer)
940       addPass(createAMDGPUReplaceLDSUseWithPointerPass());
941 
942     addPass(createAMDGPULowerModuleLDSPass());
943   }
944 
945   if (TM.getOptLevel() > CodeGenOpt::None)
946     addPass(createInferAddressSpacesPass());
947 
948   addPass(createAtomicExpandPass());
949 
950   if (TM.getOptLevel() > CodeGenOpt::None) {
951     addPass(createAMDGPUPromoteAlloca());
952 
953     if (EnableSROA)
954       addPass(createSROAPass());
955     if (isPassEnabled(EnableScalarIRPasses))
956       addStraightLineScalarOptimizationPasses();
957 
958     if (EnableAMDGPUAliasAnalysis) {
959       addPass(createAMDGPUAAWrapperPass());
960       addPass(createExternalAAWrapperPass([](Pass &P, Function &,
961                                              AAResults &AAR) {
962         if (auto *WrapperPass = P.getAnalysisIfAvailable<AMDGPUAAWrapperPass>())
963           AAR.addAAResult(WrapperPass->getResult());
964         }));
965     }
966 
967     if (TM.getTargetTriple().getArch() == Triple::amdgcn) {
968       // TODO: May want to move later or split into an early and late one.
969       addPass(createAMDGPUCodeGenPreparePass());
970     }
971   }
972 
973   TargetPassConfig::addIRPasses();
974 
975   // EarlyCSE is not always strong enough to clean up what LSR produces. For
976   // example, GVN can combine
977   //
978   //   %0 = add %a, %b
979   //   %1 = add %b, %a
980   //
981   // and
982   //
983   //   %0 = shl nsw %a, 2
984   //   %1 = shl %a, 2
985   //
986   // but EarlyCSE can do neither of them.
987   if (isPassEnabled(EnableScalarIRPasses))
988     addEarlyCSEOrGVNPass();
989 }
990 
addCodeGenPrepare()991 void AMDGPUPassConfig::addCodeGenPrepare() {
992   if (TM->getTargetTriple().getArch() == Triple::amdgcn) {
993     addPass(createAMDGPUAttributorPass());
994 
995     // FIXME: This pass adds 2 hacky attributes that can be replaced with an
996     // analysis, and should be removed.
997     addPass(createAMDGPUAnnotateKernelFeaturesPass());
998   }
999 
1000   if (TM->getTargetTriple().getArch() == Triple::amdgcn &&
1001       EnableLowerKernelArguments)
1002     addPass(createAMDGPULowerKernelArgumentsPass());
1003 
1004   TargetPassConfig::addCodeGenPrepare();
1005 
1006   if (isPassEnabled(EnableLoadStoreVectorizer))
1007     addPass(createLoadStoreVectorizerPass());
1008 
1009   // LowerSwitch pass may introduce unreachable blocks that can
1010   // cause unexpected behavior for subsequent passes. Placing it
1011   // here seems better that these blocks would get cleaned up by
1012   // UnreachableBlockElim inserted next in the pass flow.
1013   addPass(createLowerSwitchPass());
1014 }
1015 
addPreISel()1016 bool AMDGPUPassConfig::addPreISel() {
1017   if (TM->getOptLevel() > CodeGenOpt::None)
1018     addPass(createFlattenCFGPass());
1019   return false;
1020 }
1021 
addInstSelector()1022 bool AMDGPUPassConfig::addInstSelector() {
1023   addPass(createAMDGPUISelDag(&getAMDGPUTargetMachine(), getOptLevel()));
1024   return false;
1025 }
1026 
addGCPasses()1027 bool AMDGPUPassConfig::addGCPasses() {
1028   // Do nothing. GC is not supported.
1029   return false;
1030 }
1031 
1032 llvm::ScheduleDAGInstrs *
createMachineScheduler(MachineSchedContext * C) const1033 AMDGPUPassConfig::createMachineScheduler(MachineSchedContext *C) const {
1034   ScheduleDAGMILive *DAG = createGenericSchedLive(C);
1035   DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
1036   return DAG;
1037 }
1038 
1039 //===----------------------------------------------------------------------===//
1040 // GCN Pass Setup
1041 //===----------------------------------------------------------------------===//
1042 
createMachineScheduler(MachineSchedContext * C) const1043 ScheduleDAGInstrs *GCNPassConfig::createMachineScheduler(
1044   MachineSchedContext *C) const {
1045   const GCNSubtarget &ST = C->MF->getSubtarget<GCNSubtarget>();
1046   if (ST.enableSIScheduler())
1047     return createSIMachineScheduler(C);
1048   return createGCNMaxOccupancyMachineScheduler(C);
1049 }
1050 
addPreISel()1051 bool GCNPassConfig::addPreISel() {
1052   AMDGPUPassConfig::addPreISel();
1053 
1054   if (TM->getOptLevel() > CodeGenOpt::None)
1055     addPass(createAMDGPULateCodeGenPreparePass());
1056 
1057   if (isPassEnabled(EnableAtomicOptimizations, CodeGenOpt::Less)) {
1058     addPass(createAMDGPUAtomicOptimizerPass());
1059   }
1060 
1061   if (TM->getOptLevel() > CodeGenOpt::None)
1062     addPass(createSinkingPass());
1063 
1064   // Merge divergent exit nodes. StructurizeCFG won't recognize the multi-exit
1065   // regions formed by them.
1066   addPass(&AMDGPUUnifyDivergentExitNodesID);
1067   if (!LateCFGStructurize) {
1068     if (EnableStructurizerWorkarounds) {
1069       addPass(createFixIrreduciblePass());
1070       addPass(createUnifyLoopExitsPass());
1071     }
1072     addPass(createStructurizeCFGPass(false)); // true -> SkipUniformRegions
1073   }
1074   addPass(createAMDGPUAnnotateUniformValues());
1075   if (!LateCFGStructurize) {
1076     addPass(createSIAnnotateControlFlowPass());
1077   }
1078   addPass(createLCSSAPass());
1079 
1080   if (TM->getOptLevel() > CodeGenOpt::Less)
1081     addPass(&AMDGPUPerfHintAnalysisID);
1082 
1083   return false;
1084 }
1085 
addMachineSSAOptimization()1086 void GCNPassConfig::addMachineSSAOptimization() {
1087   TargetPassConfig::addMachineSSAOptimization();
1088 
1089   // We want to fold operands after PeepholeOptimizer has run (or as part of
1090   // it), because it will eliminate extra copies making it easier to fold the
1091   // real source operand. We want to eliminate dead instructions after, so that
1092   // we see fewer uses of the copies. We then need to clean up the dead
1093   // instructions leftover after the operands are folded as well.
1094   //
1095   // XXX - Can we get away without running DeadMachineInstructionElim again?
1096   addPass(&SIFoldOperandsID);
1097   if (EnableDPPCombine)
1098     addPass(&GCNDPPCombineID);
1099   addPass(&SILoadStoreOptimizerID);
1100   if (isPassEnabled(EnableSDWAPeephole)) {
1101     addPass(&SIPeepholeSDWAID);
1102     addPass(&EarlyMachineLICMID);
1103     addPass(&MachineCSEID);
1104     addPass(&SIFoldOperandsID);
1105   }
1106   addPass(&DeadMachineInstructionElimID);
1107   addPass(createSIShrinkInstructionsPass());
1108 }
1109 
addILPOpts()1110 bool GCNPassConfig::addILPOpts() {
1111   if (EnableEarlyIfConversion)
1112     addPass(&EarlyIfConverterID);
1113 
1114   TargetPassConfig::addILPOpts();
1115   return false;
1116 }
1117 
addInstSelector()1118 bool GCNPassConfig::addInstSelector() {
1119   AMDGPUPassConfig::addInstSelector();
1120   addPass(&SIFixSGPRCopiesID);
1121   addPass(createSILowerI1CopiesPass());
1122   return false;
1123 }
1124 
addIRTranslator()1125 bool GCNPassConfig::addIRTranslator() {
1126   addPass(new IRTranslator(getOptLevel()));
1127   return false;
1128 }
1129 
addPreLegalizeMachineIR()1130 void GCNPassConfig::addPreLegalizeMachineIR() {
1131   bool IsOptNone = getOptLevel() == CodeGenOpt::None;
1132   addPass(createAMDGPUPreLegalizeCombiner(IsOptNone));
1133   addPass(new Localizer());
1134 }
1135 
addLegalizeMachineIR()1136 bool GCNPassConfig::addLegalizeMachineIR() {
1137   addPass(new Legalizer());
1138   return false;
1139 }
1140 
addPreRegBankSelect()1141 void GCNPassConfig::addPreRegBankSelect() {
1142   bool IsOptNone = getOptLevel() == CodeGenOpt::None;
1143   addPass(createAMDGPUPostLegalizeCombiner(IsOptNone));
1144 }
1145 
addRegBankSelect()1146 bool GCNPassConfig::addRegBankSelect() {
1147   addPass(new RegBankSelect());
1148   return false;
1149 }
1150 
addPreGlobalInstructionSelect()1151 void GCNPassConfig::addPreGlobalInstructionSelect() {
1152   bool IsOptNone = getOptLevel() == CodeGenOpt::None;
1153   addPass(createAMDGPURegBankCombiner(IsOptNone));
1154 }
1155 
addGlobalInstructionSelect()1156 bool GCNPassConfig::addGlobalInstructionSelect() {
1157   addPass(new InstructionSelect(getOptLevel()));
1158   return false;
1159 }
1160 
addPreRegAlloc()1161 void GCNPassConfig::addPreRegAlloc() {
1162   if (LateCFGStructurize) {
1163     addPass(createAMDGPUMachineCFGStructurizerPass());
1164   }
1165 }
1166 
addFastRegAlloc()1167 void GCNPassConfig::addFastRegAlloc() {
1168   // FIXME: We have to disable the verifier here because of PHIElimination +
1169   // TwoAddressInstructions disabling it.
1170 
1171   // This must be run immediately after phi elimination and before
1172   // TwoAddressInstructions, otherwise the processing of the tied operand of
1173   // SI_ELSE will introduce a copy of the tied operand source after the else.
1174   insertPass(&PHIEliminationID, &SILowerControlFlowID, false);
1175 
1176   insertPass(&TwoAddressInstructionPassID, &SIWholeQuadModeID);
1177   insertPass(&TwoAddressInstructionPassID, &SIPreAllocateWWMRegsID);
1178 
1179   TargetPassConfig::addFastRegAlloc();
1180 }
1181 
addOptimizedRegAlloc()1182 void GCNPassConfig::addOptimizedRegAlloc() {
1183   // Allow the scheduler to run before SIWholeQuadMode inserts exec manipulation
1184   // instructions that cause scheduling barriers.
1185   insertPass(&MachineSchedulerID, &SIWholeQuadModeID);
1186   insertPass(&MachineSchedulerID, &SIPreAllocateWWMRegsID);
1187 
1188   if (OptExecMaskPreRA)
1189     insertPass(&MachineSchedulerID, &SIOptimizeExecMaskingPreRAID);
1190 
1191   if (isPassEnabled(EnablePreRAOptimizations))
1192     insertPass(&RenameIndependentSubregsID, &GCNPreRAOptimizationsID);
1193 
1194   // This is not an essential optimization and it has a noticeable impact on
1195   // compilation time, so we only enable it from O2.
1196   if (TM->getOptLevel() > CodeGenOpt::Less)
1197     insertPass(&MachineSchedulerID, &SIFormMemoryClausesID);
1198 
1199   // FIXME: when an instruction has a Killed operand, and the instruction is
1200   // inside a bundle, seems only the BUNDLE instruction appears as the Kills of
1201   // the register in LiveVariables, this would trigger a failure in verifier,
1202   // we should fix it and enable the verifier.
1203   if (OptVGPRLiveRange)
1204     insertPass(&LiveVariablesID, &SIOptimizeVGPRLiveRangeID, false);
1205   // This must be run immediately after phi elimination and before
1206   // TwoAddressInstructions, otherwise the processing of the tied operand of
1207   // SI_ELSE will introduce a copy of the tied operand source after the else.
1208   insertPass(&PHIEliminationID, &SILowerControlFlowID, false);
1209 
1210   if (EnableDCEInRA)
1211     insertPass(&DetectDeadLanesID, &DeadMachineInstructionElimID);
1212 
1213   TargetPassConfig::addOptimizedRegAlloc();
1214 }
1215 
addPreRewrite()1216 bool GCNPassConfig::addPreRewrite() {
1217   if (EnableRegReassign)
1218     addPass(&GCNNSAReassignID);
1219   return true;
1220 }
1221 
createSGPRAllocPass(bool Optimized)1222 FunctionPass *GCNPassConfig::createSGPRAllocPass(bool Optimized) {
1223   // Initialize the global default.
1224   llvm::call_once(InitializeDefaultSGPRRegisterAllocatorFlag,
1225                   initializeDefaultSGPRRegisterAllocatorOnce);
1226 
1227   RegisterRegAlloc::FunctionPassCtor Ctor = SGPRRegisterRegAlloc::getDefault();
1228   if (Ctor != useDefaultRegisterAllocator)
1229     return Ctor();
1230 
1231   if (Optimized)
1232     return createGreedyRegisterAllocator(onlyAllocateSGPRs);
1233 
1234   return createFastRegisterAllocator(onlyAllocateSGPRs, false);
1235 }
1236 
createVGPRAllocPass(bool Optimized)1237 FunctionPass *GCNPassConfig::createVGPRAllocPass(bool Optimized) {
1238   // Initialize the global default.
1239   llvm::call_once(InitializeDefaultVGPRRegisterAllocatorFlag,
1240                   initializeDefaultVGPRRegisterAllocatorOnce);
1241 
1242   RegisterRegAlloc::FunctionPassCtor Ctor = VGPRRegisterRegAlloc::getDefault();
1243   if (Ctor != useDefaultRegisterAllocator)
1244     return Ctor();
1245 
1246   if (Optimized)
1247     return createGreedyVGPRRegisterAllocator();
1248 
1249   return createFastVGPRRegisterAllocator();
1250 }
1251 
createRegAllocPass(bool Optimized)1252 FunctionPass *GCNPassConfig::createRegAllocPass(bool Optimized) {
1253   llvm_unreachable("should not be used");
1254 }
1255 
1256 static const char RegAllocOptNotSupportedMessage[] =
1257   "-regalloc not supported with amdgcn. Use -sgpr-regalloc and -vgpr-regalloc";
1258 
addRegAssignAndRewriteFast()1259 bool GCNPassConfig::addRegAssignAndRewriteFast() {
1260   if (!usingDefaultRegAlloc())
1261     report_fatal_error(RegAllocOptNotSupportedMessage);
1262 
1263   addPass(createSGPRAllocPass(false));
1264 
1265   // Equivalent of PEI for SGPRs.
1266   addPass(&SILowerSGPRSpillsID);
1267 
1268   addPass(createVGPRAllocPass(false));
1269   return true;
1270 }
1271 
addRegAssignAndRewriteOptimized()1272 bool GCNPassConfig::addRegAssignAndRewriteOptimized() {
1273   if (!usingDefaultRegAlloc())
1274     report_fatal_error(RegAllocOptNotSupportedMessage);
1275 
1276   addPass(createSGPRAllocPass(true));
1277 
1278   // Commit allocated register changes. This is mostly necessary because too
1279   // many things rely on the use lists of the physical registers, such as the
1280   // verifier. This is only necessary with allocators which use LiveIntervals,
1281   // since FastRegAlloc does the replacements itself.
1282   addPass(createVirtRegRewriter(false));
1283 
1284   // Equivalent of PEI for SGPRs.
1285   addPass(&SILowerSGPRSpillsID);
1286 
1287   addPass(createVGPRAllocPass(true));
1288 
1289   addPreRewrite();
1290   addPass(&VirtRegRewriterID);
1291 
1292   return true;
1293 }
1294 
addPostRegAlloc()1295 void GCNPassConfig::addPostRegAlloc() {
1296   addPass(&SIFixVGPRCopiesID);
1297   if (getOptLevel() > CodeGenOpt::None)
1298     addPass(&SIOptimizeExecMaskingID);
1299   TargetPassConfig::addPostRegAlloc();
1300 }
1301 
addPreSched2()1302 void GCNPassConfig::addPreSched2() {
1303   addPass(&SIPostRABundlerID);
1304 }
1305 
addPreEmitPass()1306 void GCNPassConfig::addPreEmitPass() {
1307   addPass(createSIMemoryLegalizerPass());
1308   addPass(createSIInsertWaitcntsPass());
1309 
1310   if (TM->getOptLevel() > CodeGenOpt::None)
1311     addPass(createSIShrinkInstructionsPass());
1312 
1313   addPass(createSIModeRegisterPass());
1314 
1315   if (getOptLevel() > CodeGenOpt::None)
1316     addPass(&SIInsertHardClausesID);
1317 
1318   addPass(&SILateBranchLoweringPassID);
1319   if (getOptLevel() > CodeGenOpt::None)
1320     addPass(&SIPreEmitPeepholeID);
1321   // The hazard recognizer that runs as part of the post-ra scheduler does not
1322   // guarantee to be able handle all hazards correctly. This is because if there
1323   // are multiple scheduling regions in a basic block, the regions are scheduled
1324   // bottom up, so when we begin to schedule a region we don't know what
1325   // instructions were emitted directly before it.
1326   //
1327   // Here we add a stand-alone hazard recognizer pass which can handle all
1328   // cases.
1329   addPass(&PostRAHazardRecognizerID);
1330   addPass(&BranchRelaxationPassID);
1331 }
1332 
createPassConfig(PassManagerBase & PM)1333 TargetPassConfig *GCNTargetMachine::createPassConfig(PassManagerBase &PM) {
1334   return new GCNPassConfig(*this, PM);
1335 }
1336 
createDefaultFuncInfoYAML() const1337 yaml::MachineFunctionInfo *GCNTargetMachine::createDefaultFuncInfoYAML() const {
1338   return new yaml::SIMachineFunctionInfo();
1339 }
1340 
1341 yaml::MachineFunctionInfo *
convertFuncInfoToYAML(const MachineFunction & MF) const1342 GCNTargetMachine::convertFuncInfoToYAML(const MachineFunction &MF) const {
1343   const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1344   return new yaml::SIMachineFunctionInfo(
1345       *MFI, *MF.getSubtarget().getRegisterInfo(), MF);
1346 }
1347 
parseMachineFunctionInfo(const yaml::MachineFunctionInfo & MFI_,PerFunctionMIParsingState & PFS,SMDiagnostic & Error,SMRange & SourceRange) const1348 bool GCNTargetMachine::parseMachineFunctionInfo(
1349     const yaml::MachineFunctionInfo &MFI_, PerFunctionMIParsingState &PFS,
1350     SMDiagnostic &Error, SMRange &SourceRange) const {
1351   const yaml::SIMachineFunctionInfo &YamlMFI =
1352       reinterpret_cast<const yaml::SIMachineFunctionInfo &>(MFI_);
1353   MachineFunction &MF = PFS.MF;
1354   SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1355 
1356   if (MFI->initializeBaseYamlFields(YamlMFI, MF, PFS, Error, SourceRange))
1357     return true;
1358 
1359   if (MFI->Occupancy == 0) {
1360     // Fixup the subtarget dependent default value.
1361     const GCNSubtarget &ST = MF.getSubtarget<GCNSubtarget>();
1362     MFI->Occupancy = ST.computeOccupancy(MF.getFunction(), MFI->getLDSSize());
1363   }
1364 
1365   auto parseRegister = [&](const yaml::StringValue &RegName, Register &RegVal) {
1366     Register TempReg;
1367     if (parseNamedRegisterReference(PFS, TempReg, RegName.Value, Error)) {
1368       SourceRange = RegName.SourceRange;
1369       return true;
1370     }
1371     RegVal = TempReg;
1372 
1373     return false;
1374   };
1375 
1376   auto diagnoseRegisterClass = [&](const yaml::StringValue &RegName) {
1377     // Create a diagnostic for a the register string literal.
1378     const MemoryBuffer &Buffer =
1379         *PFS.SM->getMemoryBuffer(PFS.SM->getMainFileID());
1380     Error = SMDiagnostic(*PFS.SM, SMLoc(), Buffer.getBufferIdentifier(), 1,
1381                          RegName.Value.size(), SourceMgr::DK_Error,
1382                          "incorrect register class for field", RegName.Value,
1383                          None, None);
1384     SourceRange = RegName.SourceRange;
1385     return true;
1386   };
1387 
1388   if (parseRegister(YamlMFI.ScratchRSrcReg, MFI->ScratchRSrcReg) ||
1389       parseRegister(YamlMFI.FrameOffsetReg, MFI->FrameOffsetReg) ||
1390       parseRegister(YamlMFI.StackPtrOffsetReg, MFI->StackPtrOffsetReg))
1391     return true;
1392 
1393   if (MFI->ScratchRSrcReg != AMDGPU::PRIVATE_RSRC_REG &&
1394       !AMDGPU::SGPR_128RegClass.contains(MFI->ScratchRSrcReg)) {
1395     return diagnoseRegisterClass(YamlMFI.ScratchRSrcReg);
1396   }
1397 
1398   if (MFI->FrameOffsetReg != AMDGPU::FP_REG &&
1399       !AMDGPU::SGPR_32RegClass.contains(MFI->FrameOffsetReg)) {
1400     return diagnoseRegisterClass(YamlMFI.FrameOffsetReg);
1401   }
1402 
1403   if (MFI->StackPtrOffsetReg != AMDGPU::SP_REG &&
1404       !AMDGPU::SGPR_32RegClass.contains(MFI->StackPtrOffsetReg)) {
1405     return diagnoseRegisterClass(YamlMFI.StackPtrOffsetReg);
1406   }
1407 
1408   auto parseAndCheckArgument = [&](const Optional<yaml::SIArgument> &A,
1409                                    const TargetRegisterClass &RC,
1410                                    ArgDescriptor &Arg, unsigned UserSGPRs,
1411                                    unsigned SystemSGPRs) {
1412     // Skip parsing if it's not present.
1413     if (!A)
1414       return false;
1415 
1416     if (A->IsRegister) {
1417       Register Reg;
1418       if (parseNamedRegisterReference(PFS, Reg, A->RegisterName.Value, Error)) {
1419         SourceRange = A->RegisterName.SourceRange;
1420         return true;
1421       }
1422       if (!RC.contains(Reg))
1423         return diagnoseRegisterClass(A->RegisterName);
1424       Arg = ArgDescriptor::createRegister(Reg);
1425     } else
1426       Arg = ArgDescriptor::createStack(A->StackOffset);
1427     // Check and apply the optional mask.
1428     if (A->Mask)
1429       Arg = ArgDescriptor::createArg(Arg, A->Mask.getValue());
1430 
1431     MFI->NumUserSGPRs += UserSGPRs;
1432     MFI->NumSystemSGPRs += SystemSGPRs;
1433     return false;
1434   };
1435 
1436   if (YamlMFI.ArgInfo &&
1437       (parseAndCheckArgument(YamlMFI.ArgInfo->PrivateSegmentBuffer,
1438                              AMDGPU::SGPR_128RegClass,
1439                              MFI->ArgInfo.PrivateSegmentBuffer, 4, 0) ||
1440        parseAndCheckArgument(YamlMFI.ArgInfo->DispatchPtr,
1441                              AMDGPU::SReg_64RegClass, MFI->ArgInfo.DispatchPtr,
1442                              2, 0) ||
1443        parseAndCheckArgument(YamlMFI.ArgInfo->QueuePtr, AMDGPU::SReg_64RegClass,
1444                              MFI->ArgInfo.QueuePtr, 2, 0) ||
1445        parseAndCheckArgument(YamlMFI.ArgInfo->KernargSegmentPtr,
1446                              AMDGPU::SReg_64RegClass,
1447                              MFI->ArgInfo.KernargSegmentPtr, 2, 0) ||
1448        parseAndCheckArgument(YamlMFI.ArgInfo->DispatchID,
1449                              AMDGPU::SReg_64RegClass, MFI->ArgInfo.DispatchID,
1450                              2, 0) ||
1451        parseAndCheckArgument(YamlMFI.ArgInfo->FlatScratchInit,
1452                              AMDGPU::SReg_64RegClass,
1453                              MFI->ArgInfo.FlatScratchInit, 2, 0) ||
1454        parseAndCheckArgument(YamlMFI.ArgInfo->PrivateSegmentSize,
1455                              AMDGPU::SGPR_32RegClass,
1456                              MFI->ArgInfo.PrivateSegmentSize, 0, 0) ||
1457        parseAndCheckArgument(YamlMFI.ArgInfo->WorkGroupIDX,
1458                              AMDGPU::SGPR_32RegClass, MFI->ArgInfo.WorkGroupIDX,
1459                              0, 1) ||
1460        parseAndCheckArgument(YamlMFI.ArgInfo->WorkGroupIDY,
1461                              AMDGPU::SGPR_32RegClass, MFI->ArgInfo.WorkGroupIDY,
1462                              0, 1) ||
1463        parseAndCheckArgument(YamlMFI.ArgInfo->WorkGroupIDZ,
1464                              AMDGPU::SGPR_32RegClass, MFI->ArgInfo.WorkGroupIDZ,
1465                              0, 1) ||
1466        parseAndCheckArgument(YamlMFI.ArgInfo->WorkGroupInfo,
1467                              AMDGPU::SGPR_32RegClass,
1468                              MFI->ArgInfo.WorkGroupInfo, 0, 1) ||
1469        parseAndCheckArgument(YamlMFI.ArgInfo->PrivateSegmentWaveByteOffset,
1470                              AMDGPU::SGPR_32RegClass,
1471                              MFI->ArgInfo.PrivateSegmentWaveByteOffset, 0, 1) ||
1472        parseAndCheckArgument(YamlMFI.ArgInfo->ImplicitArgPtr,
1473                              AMDGPU::SReg_64RegClass,
1474                              MFI->ArgInfo.ImplicitArgPtr, 0, 0) ||
1475        parseAndCheckArgument(YamlMFI.ArgInfo->ImplicitBufferPtr,
1476                              AMDGPU::SReg_64RegClass,
1477                              MFI->ArgInfo.ImplicitBufferPtr, 2, 0) ||
1478        parseAndCheckArgument(YamlMFI.ArgInfo->WorkItemIDX,
1479                              AMDGPU::VGPR_32RegClass,
1480                              MFI->ArgInfo.WorkItemIDX, 0, 0) ||
1481        parseAndCheckArgument(YamlMFI.ArgInfo->WorkItemIDY,
1482                              AMDGPU::VGPR_32RegClass,
1483                              MFI->ArgInfo.WorkItemIDY, 0, 0) ||
1484        parseAndCheckArgument(YamlMFI.ArgInfo->WorkItemIDZ,
1485                              AMDGPU::VGPR_32RegClass,
1486                              MFI->ArgInfo.WorkItemIDZ, 0, 0)))
1487     return true;
1488 
1489   MFI->Mode.IEEE = YamlMFI.Mode.IEEE;
1490   MFI->Mode.DX10Clamp = YamlMFI.Mode.DX10Clamp;
1491   MFI->Mode.FP32InputDenormals = YamlMFI.Mode.FP32InputDenormals;
1492   MFI->Mode.FP32OutputDenormals = YamlMFI.Mode.FP32OutputDenormals;
1493   MFI->Mode.FP64FP16InputDenormals = YamlMFI.Mode.FP64FP16InputDenormals;
1494   MFI->Mode.FP64FP16OutputDenormals = YamlMFI.Mode.FP64FP16OutputDenormals;
1495 
1496   return false;
1497 }
1498