xref: /freebsd/contrib/llvm-project/llvm/lib/Target/AArch64/AArch64TargetMachine.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 //===-- AArch64TargetMachine.cpp - Define TargetMachine for AArch64 -------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //
10 //===----------------------------------------------------------------------===//
11 
12 #include "AArch64TargetMachine.h"
13 #include "AArch64.h"
14 #include "AArch64MachineFunctionInfo.h"
15 #include "AArch64MachineScheduler.h"
16 #include "AArch64MacroFusion.h"
17 #include "AArch64Subtarget.h"
18 #include "AArch64TargetObjectFile.h"
19 #include "AArch64TargetTransformInfo.h"
20 #include "MCTargetDesc/AArch64MCTargetDesc.h"
21 #include "TargetInfo/AArch64TargetInfo.h"
22 #include "llvm/ADT/STLExtras.h"
23 #include "llvm/Analysis/TargetTransformInfo.h"
24 #include "llvm/Analysis/ValueTracking.h"
25 #include "llvm/CodeGen/CFIFixup.h"
26 #include "llvm/CodeGen/CSEConfigBase.h"
27 #include "llvm/CodeGen/GlobalISel/CSEInfo.h"
28 #include "llvm/CodeGen/GlobalISel/IRTranslator.h"
29 #include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
30 #include "llvm/CodeGen/GlobalISel/Legalizer.h"
31 #include "llvm/CodeGen/GlobalISel/LoadStoreOpt.h"
32 #include "llvm/CodeGen/GlobalISel/Localizer.h"
33 #include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
34 #include "llvm/CodeGen/MIRParser/MIParser.h"
35 #include "llvm/CodeGen/MachineScheduler.h"
36 #include "llvm/CodeGen/Passes.h"
37 #include "llvm/CodeGen/TargetInstrInfo.h"
38 #include "llvm/CodeGen/TargetPassConfig.h"
39 #include "llvm/IR/Attributes.h"
40 #include "llvm/IR/Function.h"
41 #include "llvm/InitializePasses.h"
42 #include "llvm/MC/MCAsmInfo.h"
43 #include "llvm/MC/MCTargetOptions.h"
44 #include "llvm/MC/TargetRegistry.h"
45 #include "llvm/Pass.h"
46 #include "llvm/Passes/PassBuilder.h"
47 #include "llvm/Support/CodeGen.h"
48 #include "llvm/Support/CommandLine.h"
49 #include "llvm/Target/TargetLoweringObjectFile.h"
50 #include "llvm/Target/TargetOptions.h"
51 #include "llvm/TargetParser/Triple.h"
52 #include "llvm/Transforms/CFGuard.h"
53 #include "llvm/Transforms/Scalar.h"
54 #include "llvm/Transforms/Vectorize/LoopIdiomVectorize.h"
55 #include <memory>
56 #include <optional>
57 #include <string>
58 
59 using namespace llvm;
60 
61 static cl::opt<bool> EnableCCMP("aarch64-enable-ccmp",
62                                 cl::desc("Enable the CCMP formation pass"),
63                                 cl::init(true), cl::Hidden);
64 
65 static cl::opt<bool>
66     EnableCondBrTuning("aarch64-enable-cond-br-tune",
67                        cl::desc("Enable the conditional branch tuning pass"),
68                        cl::init(true), cl::Hidden);
69 
70 static cl::opt<bool> EnableAArch64CopyPropagation(
71     "aarch64-enable-copy-propagation",
72     cl::desc("Enable the copy propagation with AArch64 copy instr"),
73     cl::init(true), cl::Hidden);
74 
75 static cl::opt<bool> EnableMCR("aarch64-enable-mcr",
76                                cl::desc("Enable the machine combiner pass"),
77                                cl::init(true), cl::Hidden);
78 
79 static cl::opt<bool> EnableStPairSuppress("aarch64-enable-stp-suppress",
80                                           cl::desc("Suppress STP for AArch64"),
81                                           cl::init(true), cl::Hidden);
82 
83 static cl::opt<bool> EnableAdvSIMDScalar(
84     "aarch64-enable-simd-scalar",
85     cl::desc("Enable use of AdvSIMD scalar integer instructions"),
86     cl::init(false), cl::Hidden);
87 
88 static cl::opt<bool>
89     EnablePromoteConstant("aarch64-enable-promote-const",
90                           cl::desc("Enable the promote constant pass"),
91                           cl::init(true), cl::Hidden);
92 
93 static cl::opt<bool> EnableCollectLOH(
94     "aarch64-enable-collect-loh",
95     cl::desc("Enable the pass that emits the linker optimization hints (LOH)"),
96     cl::init(true), cl::Hidden);
97 
98 static cl::opt<bool>
99     EnableDeadRegisterElimination("aarch64-enable-dead-defs", cl::Hidden,
100                                   cl::desc("Enable the pass that removes dead"
101                                            " definitons and replaces stores to"
102                                            " them with stores to the zero"
103                                            " register"),
104                                   cl::init(true));
105 
106 static cl::opt<bool> EnableRedundantCopyElimination(
107     "aarch64-enable-copyelim",
108     cl::desc("Enable the redundant copy elimination pass"), cl::init(true),
109     cl::Hidden);
110 
111 static cl::opt<bool> EnableLoadStoreOpt("aarch64-enable-ldst-opt",
112                                         cl::desc("Enable the load/store pair"
113                                                  " optimization pass"),
114                                         cl::init(true), cl::Hidden);
115 
116 static cl::opt<bool> EnableAtomicTidy(
117     "aarch64-enable-atomic-cfg-tidy", cl::Hidden,
118     cl::desc("Run SimplifyCFG after expanding atomic operations"
119              " to make use of cmpxchg flow-based information"),
120     cl::init(true));
121 
122 static cl::opt<bool>
123 EnableEarlyIfConversion("aarch64-enable-early-ifcvt", cl::Hidden,
124                         cl::desc("Run early if-conversion"),
125                         cl::init(true));
126 
127 static cl::opt<bool>
128     EnableCondOpt("aarch64-enable-condopt",
129                   cl::desc("Enable the condition optimizer pass"),
130                   cl::init(true), cl::Hidden);
131 
132 static cl::opt<bool>
133     EnableGEPOpt("aarch64-enable-gep-opt", cl::Hidden,
134                  cl::desc("Enable optimizations on complex GEPs"),
135                  cl::init(false));
136 
137 static cl::opt<bool>
138     EnableSelectOpt("aarch64-select-opt", cl::Hidden,
139                     cl::desc("Enable select to branch optimizations"),
140                     cl::init(true));
141 
142 static cl::opt<bool>
143     BranchRelaxation("aarch64-enable-branch-relax", cl::Hidden, cl::init(true),
144                      cl::desc("Relax out of range conditional branches"));
145 
146 static cl::opt<bool> EnableCompressJumpTables(
147     "aarch64-enable-compress-jump-tables", cl::Hidden, cl::init(true),
148     cl::desc("Use smallest entry possible for jump tables"));
149 
150 // FIXME: Unify control over GlobalMerge.
151 static cl::opt<cl::boolOrDefault>
152     EnableGlobalMerge("aarch64-enable-global-merge", cl::Hidden,
153                       cl::desc("Enable the global merge pass"));
154 
155 static cl::opt<bool>
156     EnableLoopDataPrefetch("aarch64-enable-loop-data-prefetch", cl::Hidden,
157                            cl::desc("Enable the loop data prefetch pass"),
158                            cl::init(true));
159 
160 static cl::opt<int> EnableGlobalISelAtO(
161     "aarch64-enable-global-isel-at-O", cl::Hidden,
162     cl::desc("Enable GlobalISel at or below an opt level (-1 to disable)"),
163     cl::init(0));
164 
165 static cl::opt<bool>
166     EnableSVEIntrinsicOpts("aarch64-enable-sve-intrinsic-opts", cl::Hidden,
167                            cl::desc("Enable SVE intrinsic opts"),
168                            cl::init(true));
169 
170 static cl::opt<bool> EnableFalkorHWPFFix("aarch64-enable-falkor-hwpf-fix",
171                                          cl::init(true), cl::Hidden);
172 
173 static cl::opt<bool>
174     EnableBranchTargets("aarch64-enable-branch-targets", cl::Hidden,
175                         cl::desc("Enable the AArch64 branch target pass"),
176                         cl::init(true));
177 
178 static cl::opt<unsigned> SVEVectorBitsMaxOpt(
179     "aarch64-sve-vector-bits-max",
180     cl::desc("Assume SVE vector registers are at most this big, "
181              "with zero meaning no maximum size is assumed."),
182     cl::init(0), cl::Hidden);
183 
184 static cl::opt<unsigned> SVEVectorBitsMinOpt(
185     "aarch64-sve-vector-bits-min",
186     cl::desc("Assume SVE vector registers are at least this big, "
187              "with zero meaning no minimum size is assumed."),
188     cl::init(0), cl::Hidden);
189 
190 static cl::opt<bool> ForceStreaming(
191     "force-streaming",
192     cl::desc("Force the use of streaming code for all functions"),
193     cl::init(false), cl::Hidden);
194 
195 static cl::opt<bool> ForceStreamingCompatible(
196     "force-streaming-compatible",
197     cl::desc("Force the use of streaming-compatible code for all functions"),
198     cl::init(false), cl::Hidden);
199 
200 extern cl::opt<bool> EnableHomogeneousPrologEpilog;
201 
202 static cl::opt<bool> EnableGISelLoadStoreOptPreLegal(
203     "aarch64-enable-gisel-ldst-prelegal",
204     cl::desc("Enable GlobalISel's pre-legalizer load/store optimization pass"),
205     cl::init(true), cl::Hidden);
206 
207 static cl::opt<bool> EnableGISelLoadStoreOptPostLegal(
208     "aarch64-enable-gisel-ldst-postlegal",
209     cl::desc("Enable GlobalISel's post-legalizer load/store optimization pass"),
210     cl::init(false), cl::Hidden);
211 
212 static cl::opt<bool>
213     EnableSinkFold("aarch64-enable-sink-fold",
214                    cl::desc("Enable sinking and folding of instruction copies"),
215                    cl::init(true), cl::Hidden);
216 
217 static cl::opt<bool>
218     EnableMachinePipeliner("aarch64-enable-pipeliner",
219                            cl::desc("Enable Machine Pipeliner for AArch64"),
220                            cl::init(false), cl::Hidden);
221 
LLVMInitializeAArch64Target()222 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeAArch64Target() {
223   // Register the target.
224   RegisterTargetMachine<AArch64leTargetMachine> X(getTheAArch64leTarget());
225   RegisterTargetMachine<AArch64beTargetMachine> Y(getTheAArch64beTarget());
226   RegisterTargetMachine<AArch64leTargetMachine> Z(getTheARM64Target());
227   RegisterTargetMachine<AArch64leTargetMachine> W(getTheARM64_32Target());
228   RegisterTargetMachine<AArch64leTargetMachine> V(getTheAArch64_32Target());
229   auto PR = PassRegistry::getPassRegistry();
230   initializeGlobalISel(*PR);
231   initializeAArch64A53Fix835769Pass(*PR);
232   initializeAArch64A57FPLoadBalancingPass(*PR);
233   initializeAArch64AdvSIMDScalarPass(*PR);
234   initializeAArch64BranchTargetsPass(*PR);
235   initializeAArch64CollectLOHPass(*PR);
236   initializeAArch64CompressJumpTablesPass(*PR);
237   initializeAArch64ConditionalComparesPass(*PR);
238   initializeAArch64ConditionOptimizerPass(*PR);
239   initializeAArch64DeadRegisterDefinitionsPass(*PR);
240   initializeAArch64ExpandPseudoPass(*PR);
241   initializeAArch64LoadStoreOptPass(*PR);
242   initializeAArch64MIPeepholeOptPass(*PR);
243   initializeAArch64SIMDInstrOptPass(*PR);
244   initializeAArch64O0PreLegalizerCombinerPass(*PR);
245   initializeAArch64PreLegalizerCombinerPass(*PR);
246   initializeAArch64PointerAuthPass(*PR);
247   initializeAArch64PostCoalescerPass(*PR);
248   initializeAArch64PostLegalizerCombinerPass(*PR);
249   initializeAArch64PostLegalizerLoweringPass(*PR);
250   initializeAArch64PostSelectOptimizePass(*PR);
251   initializeAArch64PromoteConstantPass(*PR);
252   initializeAArch64RedundantCopyEliminationPass(*PR);
253   initializeAArch64StorePairSuppressPass(*PR);
254   initializeFalkorHWPFFixPass(*PR);
255   initializeFalkorMarkStridedAccessesLegacyPass(*PR);
256   initializeLDTLSCleanupPass(*PR);
257   initializeKCFIPass(*PR);
258   initializeSMEABIPass(*PR);
259   initializeSVEIntrinsicOptsPass(*PR);
260   initializeAArch64SpeculationHardeningPass(*PR);
261   initializeAArch64SLSHardeningPass(*PR);
262   initializeAArch64StackTaggingPass(*PR);
263   initializeAArch64StackTaggingPreRAPass(*PR);
264   initializeAArch64LowerHomogeneousPrologEpilogPass(*PR);
265   initializeAArch64DAGToDAGISelLegacyPass(*PR);
266   initializeAArch64GlobalsTaggingPass(*PR);
267 }
268 
269 //===----------------------------------------------------------------------===//
270 // AArch64 Lowering public interface.
271 //===----------------------------------------------------------------------===//
createTLOF(const Triple & TT)272 static std::unique_ptr<TargetLoweringObjectFile> createTLOF(const Triple &TT) {
273   if (TT.isOSBinFormatMachO())
274     return std::make_unique<AArch64_MachoTargetObjectFile>();
275   if (TT.isOSBinFormatCOFF())
276     return std::make_unique<AArch64_COFFTargetObjectFile>();
277 
278   return std::make_unique<AArch64_ELFTargetObjectFile>();
279 }
280 
281 // Helper function to build a DataLayout string
computeDataLayout(const Triple & TT,const MCTargetOptions & Options,bool LittleEndian)282 static std::string computeDataLayout(const Triple &TT,
283                                      const MCTargetOptions &Options,
284                                      bool LittleEndian) {
285   if (TT.isOSBinFormatMachO()) {
286     if (TT.getArch() == Triple::aarch64_32)
287       return "e-m:o-p:32:32-i64:64-i128:128-n32:64-S128-Fn32";
288     return "e-m:o-i64:64-i128:128-n32:64-S128-Fn32";
289   }
290   if (TT.isOSBinFormatCOFF())
291     return "e-m:w-p:64:64-i32:32-i64:64-i128:128-n32:64-S128-Fn32";
292   std::string Endian = LittleEndian ? "e" : "E";
293   std::string Ptr32 = TT.getEnvironment() == Triple::GNUILP32 ? "-p:32:32" : "";
294   return Endian + "-m:e" + Ptr32 +
295          "-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32";
296 }
297 
computeDefaultCPU(const Triple & TT,StringRef CPU)298 static StringRef computeDefaultCPU(const Triple &TT, StringRef CPU) {
299   if (CPU.empty() && TT.isArm64e())
300     return "apple-a12";
301   return CPU;
302 }
303 
getEffectiveRelocModel(const Triple & TT,std::optional<Reloc::Model> RM)304 static Reloc::Model getEffectiveRelocModel(const Triple &TT,
305                                            std::optional<Reloc::Model> RM) {
306   // AArch64 Darwin and Windows are always PIC.
307   if (TT.isOSDarwin() || TT.isOSWindows())
308     return Reloc::PIC_;
309   // On ELF platforms the default static relocation model has a smart enough
310   // linker to cope with referencing external symbols defined in a shared
311   // library. Hence DynamicNoPIC doesn't need to be promoted to PIC.
312   if (!RM || *RM == Reloc::DynamicNoPIC)
313     return Reloc::Static;
314   return *RM;
315 }
316 
317 static CodeModel::Model
getEffectiveAArch64CodeModel(const Triple & TT,std::optional<CodeModel::Model> CM,bool JIT)318 getEffectiveAArch64CodeModel(const Triple &TT,
319                              std::optional<CodeModel::Model> CM, bool JIT) {
320   if (CM) {
321     if (*CM != CodeModel::Small && *CM != CodeModel::Tiny &&
322         *CM != CodeModel::Large) {
323       report_fatal_error(
324           "Only small, tiny and large code models are allowed on AArch64");
325     } else if (*CM == CodeModel::Tiny && !TT.isOSBinFormatELF())
326       report_fatal_error("tiny code model is only supported on ELF");
327     return *CM;
328   }
329   // The default MCJIT memory managers make no guarantees about where they can
330   // find an executable page; JITed code needs to be able to refer to globals
331   // no matter how far away they are.
332   // We should set the CodeModel::Small for Windows ARM64 in JIT mode,
333   // since with large code model LLVM generating 4 MOV instructions, and
334   // Windows doesn't support relocating these long branch (4 MOVs).
335   if (JIT && !TT.isOSWindows())
336     return CodeModel::Large;
337   return CodeModel::Small;
338 }
339 
340 /// Create an AArch64 architecture model.
341 ///
AArch64TargetMachine(const Target & T,const Triple & TT,StringRef CPU,StringRef FS,const TargetOptions & Options,std::optional<Reloc::Model> RM,std::optional<CodeModel::Model> CM,CodeGenOptLevel OL,bool JIT,bool LittleEndian)342 AArch64TargetMachine::AArch64TargetMachine(const Target &T, const Triple &TT,
343                                            StringRef CPU, StringRef FS,
344                                            const TargetOptions &Options,
345                                            std::optional<Reloc::Model> RM,
346                                            std::optional<CodeModel::Model> CM,
347                                            CodeGenOptLevel OL, bool JIT,
348                                            bool LittleEndian)
349     : LLVMTargetMachine(T,
350                         computeDataLayout(TT, Options.MCOptions, LittleEndian),
351                         TT, computeDefaultCPU(TT, CPU), FS, Options,
352                         getEffectiveRelocModel(TT, RM),
353                         getEffectiveAArch64CodeModel(TT, CM, JIT), OL),
354       TLOF(createTLOF(getTargetTriple())), isLittle(LittleEndian) {
355   initAsmInfo();
356 
357   if (TT.isOSBinFormatMachO()) {
358     this->Options.TrapUnreachable = true;
359     this->Options.NoTrapAfterNoreturn = true;
360   }
361 
362   if (getMCAsmInfo()->usesWindowsCFI()) {
363     // Unwinding can get confused if the last instruction in an
364     // exception-handling region (function, funclet, try block, etc.)
365     // is a call.
366     //
367     // FIXME: We could elide the trap if the next instruction would be in
368     // the same region anyway.
369     this->Options.TrapUnreachable = true;
370   }
371 
372   if (this->Options.TLSSize == 0) // default
373     this->Options.TLSSize = 24;
374   if ((getCodeModel() == CodeModel::Small ||
375        getCodeModel() == CodeModel::Kernel) &&
376       this->Options.TLSSize > 32)
377     // for the small (and kernel) code model, the maximum TLS size is 4GiB
378     this->Options.TLSSize = 32;
379   else if (getCodeModel() == CodeModel::Tiny && this->Options.TLSSize > 24)
380     // for the tiny code model, the maximum TLS size is 1MiB (< 16MiB)
381     this->Options.TLSSize = 24;
382 
383   // Enable GlobalISel at or below EnableGlobalISelAt0, unless this is
384   // MachO/CodeModel::Large, which GlobalISel does not support.
385   if (static_cast<int>(getOptLevel()) <= EnableGlobalISelAtO &&
386       TT.getArch() != Triple::aarch64_32 &&
387       TT.getEnvironment() != Triple::GNUILP32 &&
388       !(getCodeModel() == CodeModel::Large && TT.isOSBinFormatMachO())) {
389     setGlobalISel(true);
390     setGlobalISelAbort(GlobalISelAbortMode::Disable);
391   }
392 
393   // AArch64 supports the MachineOutliner.
394   setMachineOutliner(true);
395 
396   // AArch64 supports default outlining behaviour.
397   setSupportsDefaultOutlining(true);
398 
399   // AArch64 supports the debug entry values.
400   setSupportsDebugEntryValues(true);
401 
402   // AArch64 supports fixing up the DWARF unwind information.
403   if (!getMCAsmInfo()->usesWindowsCFI())
404     setCFIFixup(true);
405 }
406 
407 AArch64TargetMachine::~AArch64TargetMachine() = default;
408 
409 const AArch64Subtarget *
getSubtargetImpl(const Function & F) const410 AArch64TargetMachine::getSubtargetImpl(const Function &F) const {
411   Attribute CPUAttr = F.getFnAttribute("target-cpu");
412   Attribute TuneAttr = F.getFnAttribute("tune-cpu");
413   Attribute FSAttr = F.getFnAttribute("target-features");
414 
415   StringRef CPU = CPUAttr.isValid() ? CPUAttr.getValueAsString() : TargetCPU;
416   StringRef TuneCPU = TuneAttr.isValid() ? TuneAttr.getValueAsString() : CPU;
417   StringRef FS = FSAttr.isValid() ? FSAttr.getValueAsString() : TargetFS;
418   bool HasMinSize = F.hasMinSize();
419 
420   bool IsStreaming = ForceStreaming ||
421                      F.hasFnAttribute("aarch64_pstate_sm_enabled") ||
422                      F.hasFnAttribute("aarch64_pstate_sm_body");
423   bool IsStreamingCompatible = ForceStreamingCompatible ||
424                                F.hasFnAttribute("aarch64_pstate_sm_compatible");
425 
426   unsigned MinSVEVectorSize = 0;
427   unsigned MaxSVEVectorSize = 0;
428   if (F.hasFnAttribute(Attribute::VScaleRange)) {
429     ConstantRange CR = getVScaleRange(&F, 64);
430     MinSVEVectorSize = CR.getUnsignedMin().getZExtValue() * 128;
431     MaxSVEVectorSize = CR.getUnsignedMax().getZExtValue() * 128;
432   } else {
433     MinSVEVectorSize = SVEVectorBitsMinOpt;
434     MaxSVEVectorSize = SVEVectorBitsMaxOpt;
435   }
436 
437   assert(MinSVEVectorSize % 128 == 0 &&
438          "SVE requires vector length in multiples of 128!");
439   assert(MaxSVEVectorSize % 128 == 0 &&
440          "SVE requires vector length in multiples of 128!");
441   assert((MaxSVEVectorSize >= MinSVEVectorSize || MaxSVEVectorSize == 0) &&
442          "Minimum SVE vector size should not be larger than its maximum!");
443 
444   // Sanitize user input in case of no asserts
445   if (MaxSVEVectorSize != 0) {
446     MinSVEVectorSize = std::min(MinSVEVectorSize, MaxSVEVectorSize);
447     MaxSVEVectorSize = std::max(MinSVEVectorSize, MaxSVEVectorSize);
448   }
449 
450   SmallString<512> Key;
451   raw_svector_ostream(Key) << "SVEMin" << MinSVEVectorSize << "SVEMax"
452                            << MaxSVEVectorSize << "IsStreaming=" << IsStreaming
453                            << "IsStreamingCompatible=" << IsStreamingCompatible
454                            << CPU << TuneCPU << FS
455                            << "HasMinSize=" << HasMinSize;
456 
457   auto &I = SubtargetMap[Key];
458   if (!I) {
459     // This needs to be done before we create a new subtarget since any
460     // creation will depend on the TM and the code generation flags on the
461     // function that reside in TargetOptions.
462     resetTargetOptions(F);
463     I = std::make_unique<AArch64Subtarget>(
464         TargetTriple, CPU, TuneCPU, FS, *this, isLittle, MinSVEVectorSize,
465         MaxSVEVectorSize, IsStreaming, IsStreamingCompatible, HasMinSize);
466   }
467 
468   assert((!IsStreaming || I->hasSME()) && "Expected SME to be available");
469 
470   return I.get();
471 }
472 
anchor()473 void AArch64leTargetMachine::anchor() { }
474 
AArch64leTargetMachine(const Target & T,const Triple & TT,StringRef CPU,StringRef FS,const TargetOptions & Options,std::optional<Reloc::Model> RM,std::optional<CodeModel::Model> CM,CodeGenOptLevel OL,bool JIT)475 AArch64leTargetMachine::AArch64leTargetMachine(
476     const Target &T, const Triple &TT, StringRef CPU, StringRef FS,
477     const TargetOptions &Options, std::optional<Reloc::Model> RM,
478     std::optional<CodeModel::Model> CM, CodeGenOptLevel OL, bool JIT)
479     : AArch64TargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, JIT, true) {}
480 
anchor()481 void AArch64beTargetMachine::anchor() { }
482 
AArch64beTargetMachine(const Target & T,const Triple & TT,StringRef CPU,StringRef FS,const TargetOptions & Options,std::optional<Reloc::Model> RM,std::optional<CodeModel::Model> CM,CodeGenOptLevel OL,bool JIT)483 AArch64beTargetMachine::AArch64beTargetMachine(
484     const Target &T, const Triple &TT, StringRef CPU, StringRef FS,
485     const TargetOptions &Options, std::optional<Reloc::Model> RM,
486     std::optional<CodeModel::Model> CM, CodeGenOptLevel OL, bool JIT)
487     : AArch64TargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, JIT, false) {}
488 
489 namespace {
490 
491 /// AArch64 Code Generator Pass Configuration Options.
492 class AArch64PassConfig : public TargetPassConfig {
493 public:
AArch64PassConfig(AArch64TargetMachine & TM,PassManagerBase & PM)494   AArch64PassConfig(AArch64TargetMachine &TM, PassManagerBase &PM)
495       : TargetPassConfig(TM, PM) {
496     if (TM.getOptLevel() != CodeGenOptLevel::None)
497       substitutePass(&PostRASchedulerID, &PostMachineSchedulerID);
498     setEnableSinkAndFold(EnableSinkFold);
499   }
500 
getAArch64TargetMachine() const501   AArch64TargetMachine &getAArch64TargetMachine() const {
502     return getTM<AArch64TargetMachine>();
503   }
504 
505   ScheduleDAGInstrs *
createMachineScheduler(MachineSchedContext * C) const506   createMachineScheduler(MachineSchedContext *C) const override {
507     const AArch64Subtarget &ST = C->MF->getSubtarget<AArch64Subtarget>();
508     ScheduleDAGMILive *DAG = createGenericSchedLive(C);
509     DAG->addMutation(createLoadClusterDAGMutation(DAG->TII, DAG->TRI));
510     DAG->addMutation(createStoreClusterDAGMutation(DAG->TII, DAG->TRI));
511     if (ST.hasFusion())
512       DAG->addMutation(createAArch64MacroFusionDAGMutation());
513     return DAG;
514   }
515 
516   ScheduleDAGInstrs *
createPostMachineScheduler(MachineSchedContext * C) const517   createPostMachineScheduler(MachineSchedContext *C) const override {
518     const AArch64Subtarget &ST = C->MF->getSubtarget<AArch64Subtarget>();
519     ScheduleDAGMI *DAG =
520         new ScheduleDAGMI(C, std::make_unique<AArch64PostRASchedStrategy>(C),
521                           /* RemoveKillFlags=*/true);
522     if (ST.hasFusion()) {
523       // Run the Macro Fusion after RA again since literals are expanded from
524       // pseudos then (v. addPreSched2()).
525       DAG->addMutation(createAArch64MacroFusionDAGMutation());
526       return DAG;
527     }
528 
529     return DAG;
530   }
531 
532   void addIRPasses()  override;
533   bool addPreISel() override;
534   void addCodeGenPrepare() override;
535   bool addInstSelector() override;
536   bool addIRTranslator() override;
537   void addPreLegalizeMachineIR() override;
538   bool addLegalizeMachineIR() override;
539   void addPreRegBankSelect() override;
540   bool addRegBankSelect() override;
541   bool addGlobalInstructionSelect() override;
542   void addMachineSSAOptimization() override;
543   bool addILPOpts() override;
544   void addPreRegAlloc() override;
545   void addPostRegAlloc() override;
546   void addPreSched2() override;
547   void addPreEmitPass() override;
548   void addPostBBSections() override;
549   void addPreEmitPass2() override;
550   bool addRegAssignAndRewriteOptimized() override;
551 
552   std::unique_ptr<CSEConfigBase> getCSEConfig() const override;
553 };
554 
555 } // end anonymous namespace
556 
registerPassBuilderCallbacks(PassBuilder & PB)557 void AArch64TargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
558 
559   PB.registerLateLoopOptimizationsEPCallback(
560       [=](LoopPassManager &LPM, OptimizationLevel Level) {
561         LPM.addPass(LoopIdiomVectorizePass());
562       });
563 }
564 
565 TargetTransformInfo
getTargetTransformInfo(const Function & F) const566 AArch64TargetMachine::getTargetTransformInfo(const Function &F) const {
567   return TargetTransformInfo(AArch64TTIImpl(this, F));
568 }
569 
createPassConfig(PassManagerBase & PM)570 TargetPassConfig *AArch64TargetMachine::createPassConfig(PassManagerBase &PM) {
571   return new AArch64PassConfig(*this, PM);
572 }
573 
getCSEConfig() const574 std::unique_ptr<CSEConfigBase> AArch64PassConfig::getCSEConfig() const {
575   return getStandardCSEConfigForOpt(TM->getOptLevel());
576 }
577 
addIRPasses()578 void AArch64PassConfig::addIRPasses() {
579   // Always expand atomic operations, we don't deal with atomicrmw or cmpxchg
580   // ourselves.
581   addPass(createAtomicExpandLegacyPass());
582 
583   // Expand any SVE vector library calls that we can't code generate directly.
584   if (EnableSVEIntrinsicOpts &&
585       TM->getOptLevel() == CodeGenOptLevel::Aggressive)
586     addPass(createSVEIntrinsicOptsPass());
587 
588   // Cmpxchg instructions are often used with a subsequent comparison to
589   // determine whether it succeeded. We can exploit existing control-flow in
590   // ldrex/strex loops to simplify this, but it needs tidying up.
591   if (TM->getOptLevel() != CodeGenOptLevel::None && EnableAtomicTidy)
592     addPass(createCFGSimplificationPass(SimplifyCFGOptions()
593                                             .forwardSwitchCondToPhi(true)
594                                             .convertSwitchRangeToICmp(true)
595                                             .convertSwitchToLookupTable(true)
596                                             .needCanonicalLoops(false)
597                                             .hoistCommonInsts(true)
598                                             .sinkCommonInsts(true)));
599 
600   // Run LoopDataPrefetch
601   //
602   // Run this before LSR to remove the multiplies involved in computing the
603   // pointer values N iterations ahead.
604   if (TM->getOptLevel() != CodeGenOptLevel::None) {
605     if (EnableLoopDataPrefetch)
606       addPass(createLoopDataPrefetchPass());
607     if (EnableFalkorHWPFFix)
608       addPass(createFalkorMarkStridedAccessesPass());
609   }
610 
611   if (EnableGEPOpt) {
612     // Call SeparateConstOffsetFromGEP pass to extract constants within indices
613     // and lower a GEP with multiple indices to either arithmetic operations or
614     // multiple GEPs with single index.
615     addPass(createSeparateConstOffsetFromGEPPass(true));
616     // Call EarlyCSE pass to find and remove subexpressions in the lowered
617     // result.
618     addPass(createEarlyCSEPass());
619     // Do loop invariant code motion in case part of the lowered result is
620     // invariant.
621     addPass(createLICMPass());
622   }
623 
624   TargetPassConfig::addIRPasses();
625 
626   if (getOptLevel() == CodeGenOptLevel::Aggressive && EnableSelectOpt)
627     addPass(createSelectOptimizePass());
628 
629   addPass(createAArch64GlobalsTaggingPass());
630   addPass(createAArch64StackTaggingPass(
631       /*IsOptNone=*/TM->getOptLevel() == CodeGenOptLevel::None));
632 
633   // Match complex arithmetic patterns
634   if (TM->getOptLevel() >= CodeGenOptLevel::Default)
635     addPass(createComplexDeinterleavingPass(TM));
636 
637   // Match interleaved memory accesses to ldN/stN intrinsics.
638   if (TM->getOptLevel() != CodeGenOptLevel::None) {
639     addPass(createInterleavedLoadCombinePass());
640     addPass(createInterleavedAccessPass());
641   }
642 
643   // Expand any functions marked with SME attributes which require special
644   // changes for the calling convention or that require the lazy-saving
645   // mechanism specified in the SME ABI.
646   addPass(createSMEABIPass());
647 
648   // Add Control Flow Guard checks.
649   if (TM->getTargetTriple().isOSWindows()) {
650     if (TM->getTargetTriple().isWindowsArm64EC())
651       addPass(createAArch64Arm64ECCallLoweringPass());
652     else
653       addPass(createCFGuardCheckPass());
654   }
655 
656   if (TM->Options.JMCInstrument)
657     addPass(createJMCInstrumenterPass());
658 }
659 
660 // Pass Pipeline Configuration
addPreISel()661 bool AArch64PassConfig::addPreISel() {
662   // Run promote constant before global merge, so that the promoted constants
663   // get a chance to be merged
664   if (TM->getOptLevel() != CodeGenOptLevel::None && EnablePromoteConstant)
665     addPass(createAArch64PromoteConstantPass());
666   // FIXME: On AArch64, this depends on the type.
667   // Basically, the addressable offsets are up to 4095 * Ty.getSizeInBytes().
668   // and the offset has to be a multiple of the related size in bytes.
669   if ((TM->getOptLevel() != CodeGenOptLevel::None &&
670        EnableGlobalMerge == cl::BOU_UNSET) ||
671       EnableGlobalMerge == cl::BOU_TRUE) {
672     bool OnlyOptimizeForSize =
673         (TM->getOptLevel() < CodeGenOptLevel::Aggressive) &&
674         (EnableGlobalMerge == cl::BOU_UNSET);
675 
676     // Merging of extern globals is enabled by default on non-Mach-O as we
677     // expect it to be generally either beneficial or harmless. On Mach-O it
678     // is disabled as we emit the .subsections_via_symbols directive which
679     // means that merging extern globals is not safe.
680     bool MergeExternalByDefault = !TM->getTargetTriple().isOSBinFormatMachO();
681 
682     // FIXME: extern global merging is only enabled when we optimise for size
683     // because there are some regressions with it also enabled for performance.
684     if (!OnlyOptimizeForSize)
685       MergeExternalByDefault = false;
686 
687     addPass(createGlobalMergePass(TM, 4095, OnlyOptimizeForSize,
688                                   MergeExternalByDefault));
689   }
690 
691   return false;
692 }
693 
addCodeGenPrepare()694 void AArch64PassConfig::addCodeGenPrepare() {
695   if (getOptLevel() != CodeGenOptLevel::None)
696     addPass(createTypePromotionLegacyPass());
697   TargetPassConfig::addCodeGenPrepare();
698 }
699 
addInstSelector()700 bool AArch64PassConfig::addInstSelector() {
701   addPass(createAArch64ISelDag(getAArch64TargetMachine(), getOptLevel()));
702 
703   // For ELF, cleanup any local-dynamic TLS accesses (i.e. combine as many
704   // references to _TLS_MODULE_BASE_ as possible.
705   if (TM->getTargetTriple().isOSBinFormatELF() &&
706       getOptLevel() != CodeGenOptLevel::None)
707     addPass(createAArch64CleanupLocalDynamicTLSPass());
708 
709   return false;
710 }
711 
addIRTranslator()712 bool AArch64PassConfig::addIRTranslator() {
713   addPass(new IRTranslator(getOptLevel()));
714   return false;
715 }
716 
addPreLegalizeMachineIR()717 void AArch64PassConfig::addPreLegalizeMachineIR() {
718   if (getOptLevel() == CodeGenOptLevel::None) {
719     addPass(createAArch64O0PreLegalizerCombiner());
720     addPass(new Localizer());
721   } else {
722     addPass(createAArch64PreLegalizerCombiner());
723     addPass(new Localizer());
724     if (EnableGISelLoadStoreOptPreLegal)
725       addPass(new LoadStoreOpt());
726   }
727 }
728 
addLegalizeMachineIR()729 bool AArch64PassConfig::addLegalizeMachineIR() {
730   addPass(new Legalizer());
731   return false;
732 }
733 
addPreRegBankSelect()734 void AArch64PassConfig::addPreRegBankSelect() {
735   bool IsOptNone = getOptLevel() == CodeGenOptLevel::None;
736   if (!IsOptNone) {
737     addPass(createAArch64PostLegalizerCombiner(IsOptNone));
738     if (EnableGISelLoadStoreOptPostLegal)
739       addPass(new LoadStoreOpt());
740   }
741   addPass(createAArch64PostLegalizerLowering());
742 }
743 
addRegBankSelect()744 bool AArch64PassConfig::addRegBankSelect() {
745   addPass(new RegBankSelect());
746   return false;
747 }
748 
addGlobalInstructionSelect()749 bool AArch64PassConfig::addGlobalInstructionSelect() {
750   addPass(new InstructionSelect(getOptLevel()));
751   if (getOptLevel() != CodeGenOptLevel::None)
752     addPass(createAArch64PostSelectOptimize());
753   return false;
754 }
755 
addMachineSSAOptimization()756 void AArch64PassConfig::addMachineSSAOptimization() {
757   // Run default MachineSSAOptimization first.
758   TargetPassConfig::addMachineSSAOptimization();
759 
760   if (TM->getOptLevel() != CodeGenOptLevel::None)
761     addPass(createAArch64MIPeepholeOptPass());
762 }
763 
addILPOpts()764 bool AArch64PassConfig::addILPOpts() {
765   if (EnableCondOpt)
766     addPass(createAArch64ConditionOptimizerPass());
767   if (EnableCCMP)
768     addPass(createAArch64ConditionalCompares());
769   if (EnableMCR)
770     addPass(&MachineCombinerID);
771   if (EnableCondBrTuning)
772     addPass(createAArch64CondBrTuning());
773   if (EnableEarlyIfConversion)
774     addPass(&EarlyIfConverterID);
775   if (EnableStPairSuppress)
776     addPass(createAArch64StorePairSuppressPass());
777   addPass(createAArch64SIMDInstrOptPass());
778   if (TM->getOptLevel() != CodeGenOptLevel::None)
779     addPass(createAArch64StackTaggingPreRAPass());
780   return true;
781 }
782 
addPreRegAlloc()783 void AArch64PassConfig::addPreRegAlloc() {
784   // Change dead register definitions to refer to the zero register.
785   if (TM->getOptLevel() != CodeGenOptLevel::None &&
786       EnableDeadRegisterElimination)
787     addPass(createAArch64DeadRegisterDefinitions());
788 
789   // Use AdvSIMD scalar instructions whenever profitable.
790   if (TM->getOptLevel() != CodeGenOptLevel::None && EnableAdvSIMDScalar) {
791     addPass(createAArch64AdvSIMDScalar());
792     // The AdvSIMD pass may produce copies that can be rewritten to
793     // be register coalescer friendly.
794     addPass(&PeepholeOptimizerID);
795   }
796   if (TM->getOptLevel() != CodeGenOptLevel::None && EnableMachinePipeliner)
797     addPass(&MachinePipelinerID);
798 }
799 
addPostRegAlloc()800 void AArch64PassConfig::addPostRegAlloc() {
801   // Remove redundant copy instructions.
802   if (TM->getOptLevel() != CodeGenOptLevel::None &&
803       EnableRedundantCopyElimination)
804     addPass(createAArch64RedundantCopyEliminationPass());
805 
806   if (TM->getOptLevel() != CodeGenOptLevel::None && usingDefaultRegAlloc())
807     // Improve performance for some FP/SIMD code for A57.
808     addPass(createAArch64A57FPLoadBalancing());
809 }
810 
addPreSched2()811 void AArch64PassConfig::addPreSched2() {
812   // Lower homogeneous frame instructions
813   if (EnableHomogeneousPrologEpilog)
814     addPass(createAArch64LowerHomogeneousPrologEpilogPass());
815   // Expand some pseudo instructions to allow proper scheduling.
816   addPass(createAArch64ExpandPseudoPass());
817   // Use load/store pair instructions when possible.
818   if (TM->getOptLevel() != CodeGenOptLevel::None) {
819     if (EnableLoadStoreOpt)
820       addPass(createAArch64LoadStoreOptimizationPass());
821   }
822   // Emit KCFI checks for indirect calls.
823   addPass(createKCFIPass());
824 
825   // The AArch64SpeculationHardeningPass destroys dominator tree and natural
826   // loop info, which is needed for the FalkorHWPFFixPass and also later on.
827   // Therefore, run the AArch64SpeculationHardeningPass before the
828   // FalkorHWPFFixPass to avoid recomputing dominator tree and natural loop
829   // info.
830   addPass(createAArch64SpeculationHardeningPass());
831 
832   if (TM->getOptLevel() != CodeGenOptLevel::None) {
833     if (EnableFalkorHWPFFix)
834       addPass(createFalkorHWPFFixPass());
835   }
836 }
837 
addPreEmitPass()838 void AArch64PassConfig::addPreEmitPass() {
839   // Machine Block Placement might have created new opportunities when run
840   // at O3, where the Tail Duplication Threshold is set to 4 instructions.
841   // Run the load/store optimizer once more.
842   if (TM->getOptLevel() >= CodeGenOptLevel::Aggressive && EnableLoadStoreOpt)
843     addPass(createAArch64LoadStoreOptimizationPass());
844 
845   if (TM->getOptLevel() >= CodeGenOptLevel::Aggressive &&
846       EnableAArch64CopyPropagation)
847     addPass(createMachineCopyPropagationPass(true));
848 
849   addPass(createAArch64A53Fix835769());
850 
851   if (TM->getTargetTriple().isOSWindows()) {
852     // Identify valid longjmp targets for Windows Control Flow Guard.
853     addPass(createCFGuardLongjmpPass());
854     // Identify valid eh continuation targets for Windows EHCont Guard.
855     addPass(createEHContGuardCatchretPass());
856   }
857 
858   if (TM->getOptLevel() != CodeGenOptLevel::None && EnableCollectLOH &&
859       TM->getTargetTriple().isOSBinFormatMachO())
860     addPass(createAArch64CollectLOHPass());
861 }
862 
addPostBBSections()863 void AArch64PassConfig::addPostBBSections() {
864   addPass(createAArch64SLSHardeningPass());
865   addPass(createAArch64PointerAuthPass());
866   if (EnableBranchTargets)
867     addPass(createAArch64BranchTargetsPass());
868   // Relax conditional branch instructions if they're otherwise out of
869   // range of their destination.
870   if (BranchRelaxation)
871     addPass(&BranchRelaxationPassID);
872 
873   if (TM->getOptLevel() != CodeGenOptLevel::None && EnableCompressJumpTables)
874     addPass(createAArch64CompressJumpTablesPass());
875 }
876 
addPreEmitPass2()877 void AArch64PassConfig::addPreEmitPass2() {
878   // SVE bundles move prefixes with destructive operations. BLR_RVMARKER pseudo
879   // instructions are lowered to bundles as well.
880   addPass(createUnpackMachineBundles(nullptr));
881 }
882 
addRegAssignAndRewriteOptimized()883 bool AArch64PassConfig::addRegAssignAndRewriteOptimized() {
884   addPass(createAArch64PostCoalescerPass());
885   return TargetPassConfig::addRegAssignAndRewriteOptimized();
886 }
887 
createMachineFunctionInfo(BumpPtrAllocator & Allocator,const Function & F,const TargetSubtargetInfo * STI) const888 MachineFunctionInfo *AArch64TargetMachine::createMachineFunctionInfo(
889     BumpPtrAllocator &Allocator, const Function &F,
890     const TargetSubtargetInfo *STI) const {
891   return AArch64FunctionInfo::create<AArch64FunctionInfo>(
892       Allocator, F, static_cast<const AArch64Subtarget *>(STI));
893 }
894 
895 yaml::MachineFunctionInfo *
createDefaultFuncInfoYAML() const896 AArch64TargetMachine::createDefaultFuncInfoYAML() const {
897   return new yaml::AArch64FunctionInfo();
898 }
899 
900 yaml::MachineFunctionInfo *
convertFuncInfoToYAML(const MachineFunction & MF) const901 AArch64TargetMachine::convertFuncInfoToYAML(const MachineFunction &MF) const {
902   const auto *MFI = MF.getInfo<AArch64FunctionInfo>();
903   return new yaml::AArch64FunctionInfo(*MFI);
904 }
905 
parseMachineFunctionInfo(const yaml::MachineFunctionInfo & MFI,PerFunctionMIParsingState & PFS,SMDiagnostic & Error,SMRange & SourceRange) const906 bool AArch64TargetMachine::parseMachineFunctionInfo(
907     const yaml::MachineFunctionInfo &MFI, PerFunctionMIParsingState &PFS,
908     SMDiagnostic &Error, SMRange &SourceRange) const {
909   const auto &YamlMFI = static_cast<const yaml::AArch64FunctionInfo &>(MFI);
910   MachineFunction &MF = PFS.MF;
911   MF.getInfo<AArch64FunctionInfo>()->initializeBaseYamlFields(YamlMFI);
912   return false;
913 }
914