xref: /freebsd/contrib/llvm-project/llvm/lib/Target/ARM/ARMTargetMachine.cpp (revision 2c2ec6bbc9cc7762a250ffe903bda6c2e44d25ff)
1 //===-- ARMTargetMachine.cpp - Define TargetMachine for ARM ---------------===//
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 "ARMTargetMachine.h"
13 #include "ARM.h"
14 #include "ARMLatencyMutations.h"
15 #include "ARMMachineFunctionInfo.h"
16 #include "ARMMacroFusion.h"
17 #include "ARMSubtarget.h"
18 #include "ARMTargetObjectFile.h"
19 #include "ARMTargetTransformInfo.h"
20 #include "MCTargetDesc/ARMMCTargetDesc.h"
21 #include "TargetInfo/ARMTargetInfo.h"
22 #include "llvm/ADT/StringRef.h"
23 #include "llvm/Analysis/TargetTransformInfo.h"
24 #include "llvm/CodeGen/ExecutionDomainFix.h"
25 #include "llvm/CodeGen/GlobalISel/CSEInfo.h"
26 #include "llvm/CodeGen/GlobalISel/CallLowering.h"
27 #include "llvm/CodeGen/GlobalISel/IRTranslator.h"
28 #include "llvm/CodeGen/GlobalISel/InstructionSelect.h"
29 #include "llvm/CodeGen/GlobalISel/Legalizer.h"
30 #include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
31 #include "llvm/CodeGen/GlobalISel/RegBankSelect.h"
32 #include "llvm/CodeGen/MIRParser/MIParser.h"
33 #include "llvm/CodeGen/MachineFunction.h"
34 #include "llvm/CodeGen/MachineScheduler.h"
35 #include "llvm/CodeGen/Passes.h"
36 #include "llvm/CodeGen/TargetPassConfig.h"
37 #include "llvm/IR/Attributes.h"
38 #include "llvm/IR/DataLayout.h"
39 #include "llvm/IR/Function.h"
40 #include "llvm/MC/TargetRegistry.h"
41 #include "llvm/Pass.h"
42 #include "llvm/Support/CodeGen.h"
43 #include "llvm/Support/CommandLine.h"
44 #include "llvm/Support/Compiler.h"
45 #include "llvm/Support/ErrorHandling.h"
46 #include "llvm/Target/TargetLoweringObjectFile.h"
47 #include "llvm/Target/TargetOptions.h"
48 #include "llvm/TargetParser/ARMTargetParser.h"
49 #include "llvm/TargetParser/TargetParser.h"
50 #include "llvm/TargetParser/Triple.h"
51 #include "llvm/Transforms/CFGuard.h"
52 #include "llvm/Transforms/IPO.h"
53 #include "llvm/Transforms/Scalar.h"
54 #include <cassert>
55 #include <memory>
56 #include <optional>
57 #include <string>
58 
59 using namespace llvm;
60 
61 static cl::opt<bool>
62 DisableA15SDOptimization("disable-a15-sd-optimization", cl::Hidden,
63                    cl::desc("Inhibit optimization of S->D register accesses on A15"),
64                    cl::init(false));
65 
66 static cl::opt<bool>
67 EnableAtomicTidy("arm-atomic-cfg-tidy", cl::Hidden,
68                  cl::desc("Run SimplifyCFG after expanding atomic operations"
69                           " to make use of cmpxchg flow-based information"),
70                  cl::init(true));
71 
72 static cl::opt<bool>
73 EnableARMLoadStoreOpt("arm-load-store-opt", cl::Hidden,
74                       cl::desc("Enable ARM load/store optimization pass"),
75                       cl::init(true));
76 
77 // FIXME: Unify control over GlobalMerge.
78 static cl::opt<cl::boolOrDefault>
79 EnableGlobalMerge("arm-global-merge", cl::Hidden,
80                   cl::desc("Enable the global merge pass"));
81 
82 namespace llvm {
83   void initializeARMExecutionDomainFixPass(PassRegistry&);
84 }
85 
86 extern "C" LLVM_ABI LLVM_EXTERNAL_VISIBILITY void LLVMInitializeARMTarget() {
87   // Register the target.
88   RegisterTargetMachine<ARMLETargetMachine> X(getTheARMLETarget());
89   RegisterTargetMachine<ARMLETargetMachine> A(getTheThumbLETarget());
90   RegisterTargetMachine<ARMBETargetMachine> Y(getTheARMBETarget());
91   RegisterTargetMachine<ARMBETargetMachine> B(getTheThumbBETarget());
92 
93   PassRegistry &Registry = *PassRegistry::getPassRegistry();
94   initializeGlobalISel(Registry);
95   initializeARMAsmPrinterPass(Registry);
96   initializeARMLoadStoreOptPass(Registry);
97   initializeARMPreAllocLoadStoreOptPass(Registry);
98   initializeARMParallelDSPPass(Registry);
99   initializeARMBranchTargetsPass(Registry);
100   initializeARMConstantIslandsPass(Registry);
101   initializeARMExecutionDomainFixPass(Registry);
102   initializeARMExpandPseudoPass(Registry);
103   initializeThumb2SizeReducePass(Registry);
104   initializeMVEVPTBlockPass(Registry);
105   initializeMVETPAndVPTOptimisationsPass(Registry);
106   initializeMVETailPredicationPass(Registry);
107   initializeARMLowOverheadLoopsPass(Registry);
108   initializeARMBlockPlacementPass(Registry);
109   initializeMVEGatherScatterLoweringPass(Registry);
110   initializeARMSLSHardeningPass(Registry);
111   initializeMVELaneInterleavingPass(Registry);
112   initializeARMFixCortexA57AES1742098Pass(Registry);
113   initializeARMDAGToDAGISelLegacyPass(Registry);
114 }
115 
116 static std::unique_ptr<TargetLoweringObjectFile> createTLOF(const Triple &TT) {
117   if (TT.isOSBinFormatMachO())
118     return std::make_unique<TargetLoweringObjectFileMachO>();
119   if (TT.isOSWindows())
120     return std::make_unique<TargetLoweringObjectFileCOFF>();
121   return std::make_unique<ARMElfTargetObjectFile>();
122 }
123 
124 static std::string computeDataLayout(const Triple &TT, StringRef CPU,
125                                      const TargetOptions &Options,
126                                      bool isLittle) {
127   auto ABI = ARM::computeTargetABI(TT, CPU, Options.MCOptions.ABIName);
128   std::string Ret;
129 
130   if (isLittle)
131     // Little endian.
132     Ret += "e";
133   else
134     // Big endian.
135     Ret += "E";
136 
137   Ret += DataLayout::getManglingComponent(TT);
138 
139   // Pointers are 32 bits and aligned to 32 bits.
140   Ret += "-p:32:32";
141 
142   // Function pointers are aligned to 8 bits (because the LSB stores the
143   // ARM/Thumb state).
144   Ret += "-Fi8";
145 
146   // ABIs other than APCS have 64 bit integers with natural alignment.
147   if (ABI != ARM::ARM_ABI_APCS)
148     Ret += "-i64:64";
149 
150   // We have 64 bits floats. The APCS ABI requires them to be aligned to 32
151   // bits, others to 64 bits. We always try to align to 64 bits.
152   if (ABI == ARM::ARM_ABI_APCS)
153     Ret += "-f64:32:64";
154 
155   // We have 128 and 64 bit vectors. The APCS ABI aligns them to 32 bits, others
156   // to 64. We always ty to give them natural alignment.
157   if (ABI == ARM::ARM_ABI_APCS)
158     Ret += "-v64:32:64-v128:32:128";
159   else if (ABI != ARM::ARM_ABI_AAPCS16)
160     Ret += "-v128:64:128";
161 
162   // Try to align aggregates to 32 bits (the default is 64 bits, which has no
163   // particular hardware support on 32-bit ARM).
164   Ret += "-a:0:32";
165 
166   // Integer registers are 32 bits.
167   Ret += "-n32";
168 
169   // The stack is 128 bit aligned on NaCl, 64 bit aligned on AAPCS and 32 bit
170   // aligned everywhere else.
171   if (TT.isOSNaCl() || ABI == ARM::ARM_ABI_AAPCS16)
172     Ret += "-S128";
173   else if (ABI == ARM::ARM_ABI_AAPCS)
174     Ret += "-S64";
175   else
176     Ret += "-S32";
177 
178   return Ret;
179 }
180 
181 static Reloc::Model getEffectiveRelocModel(const Triple &TT,
182                                            std::optional<Reloc::Model> RM) {
183   if (!RM)
184     // Default relocation model on Darwin is PIC.
185     return TT.isOSBinFormatMachO() ? Reloc::PIC_ : Reloc::Static;
186 
187   if (*RM == Reloc::ROPI || *RM == Reloc::RWPI || *RM == Reloc::ROPI_RWPI)
188     assert(TT.isOSBinFormatELF() &&
189            "ROPI/RWPI currently only supported for ELF");
190 
191   // DynamicNoPIC is only used on darwin.
192   if (*RM == Reloc::DynamicNoPIC && !TT.isOSDarwin())
193     return Reloc::Static;
194 
195   return *RM;
196 }
197 
198 /// Create an ARM architecture model.
199 ///
200 ARMBaseTargetMachine::ARMBaseTargetMachine(const Target &T, const Triple &TT,
201                                            StringRef CPU, StringRef FS,
202                                            const TargetOptions &Options,
203                                            std::optional<Reloc::Model> RM,
204                                            std::optional<CodeModel::Model> CM,
205                                            CodeGenOptLevel OL, bool isLittle)
206     : CodeGenTargetMachineImpl(T, computeDataLayout(TT, CPU, Options, isLittle),
207                                TT, CPU, FS, Options,
208                                getEffectiveRelocModel(TT, RM),
209                                getEffectiveCodeModel(CM, CodeModel::Small), OL),
210       TargetABI(ARM::computeTargetABI(TT, CPU, Options.MCOptions.ABIName)),
211       TLOF(createTLOF(getTargetTriple())), isLittle(isLittle) {
212 
213   // Default to triple-appropriate float ABI
214   if (Options.FloatABIType == FloatABI::Default) {
215     if (isTargetHardFloat())
216       this->Options.FloatABIType = FloatABI::Hard;
217     else
218       this->Options.FloatABIType = FloatABI::Soft;
219   }
220 
221   // Default to triple-appropriate EABI
222   if (Options.EABIVersion == EABI::Default ||
223       Options.EABIVersion == EABI::Unknown) {
224     // musl is compatible with glibc with regard to EABI version
225     if ((TargetTriple.getEnvironment() == Triple::GNUEABI ||
226          TargetTriple.getEnvironment() == Triple::GNUEABIT64 ||
227          TargetTriple.getEnvironment() == Triple::GNUEABIHF ||
228          TargetTriple.getEnvironment() == Triple::GNUEABIHFT64 ||
229          TargetTriple.getEnvironment() == Triple::MuslEABI ||
230          TargetTriple.getEnvironment() == Triple::MuslEABIHF ||
231          TargetTriple.getEnvironment() == Triple::OpenHOS) &&
232         !(TargetTriple.isOSWindows() || TargetTriple.isOSDarwin()))
233       this->Options.EABIVersion = EABI::GNU;
234     else
235       this->Options.EABIVersion = EABI::EABI5;
236   }
237 
238   if (TT.isOSBinFormatMachO()) {
239     this->Options.TrapUnreachable = true;
240     this->Options.NoTrapAfterNoreturn = true;
241   }
242 
243   // ARM supports the debug entry values.
244   setSupportsDebugEntryValues(true);
245 
246   initAsmInfo();
247 
248   // ARM supports the MachineOutliner.
249   setMachineOutliner(true);
250   setSupportsDefaultOutlining(true);
251 }
252 
253 ARMBaseTargetMachine::~ARMBaseTargetMachine() = default;
254 
255 MachineFunctionInfo *ARMBaseTargetMachine::createMachineFunctionInfo(
256     BumpPtrAllocator &Allocator, const Function &F,
257     const TargetSubtargetInfo *STI) const {
258   return ARMFunctionInfo::create<ARMFunctionInfo>(
259       Allocator, F, static_cast<const ARMSubtarget *>(STI));
260 }
261 
262 const ARMSubtarget *
263 ARMBaseTargetMachine::getSubtargetImpl(const Function &F) const {
264   Attribute CPUAttr = F.getFnAttribute("target-cpu");
265   Attribute FSAttr = F.getFnAttribute("target-features");
266 
267   std::string CPU =
268       CPUAttr.isValid() ? CPUAttr.getValueAsString().str() : TargetCPU;
269   std::string FS =
270       FSAttr.isValid() ? FSAttr.getValueAsString().str() : TargetFS;
271 
272   // FIXME: This is related to the code below to reset the target options,
273   // we need to know whether or not the soft float flag is set on the
274   // function before we can generate a subtarget. We also need to use
275   // it as a key for the subtarget since that can be the only difference
276   // between two functions.
277   bool SoftFloat = F.getFnAttribute("use-soft-float").getValueAsBool();
278   // If the soft float attribute is set on the function turn on the soft float
279   // subtarget feature.
280   if (SoftFloat)
281     FS += FS.empty() ? "+soft-float" : ",+soft-float";
282 
283   // Use the optminsize to identify the subtarget, but don't use it in the
284   // feature string.
285   std::string Key = CPU + FS;
286   if (F.hasMinSize())
287     Key += "+minsize";
288 
289   auto &I = SubtargetMap[Key];
290   if (!I) {
291     // This needs to be done before we create a new subtarget since any
292     // creation will depend on the TM and the code generation flags on the
293     // function that reside in TargetOptions.
294     resetTargetOptions(F);
295     I = std::make_unique<ARMSubtarget>(TargetTriple, CPU, FS, *this, isLittle,
296                                         F.hasMinSize());
297 
298     if (!I->isThumb() && !I->hasARMOps())
299       F.getContext().emitError("Function '" + F.getName() + "' uses ARM "
300           "instructions, but the target does not support ARM mode execution.");
301   }
302 
303   return I.get();
304 }
305 
306 TargetTransformInfo
307 ARMBaseTargetMachine::getTargetTransformInfo(const Function &F) const {
308   return TargetTransformInfo(std::make_unique<ARMTTIImpl>(this, F));
309 }
310 
311 ScheduleDAGInstrs *
312 ARMBaseTargetMachine::createMachineScheduler(MachineSchedContext *C) const {
313   ScheduleDAGMILive *DAG = createSchedLive(C);
314   // add DAG Mutations here.
315   const ARMSubtarget &ST = C->MF->getSubtarget<ARMSubtarget>();
316   if (ST.hasFusion())
317     DAG->addMutation(createARMMacroFusionDAGMutation());
318   return DAG;
319 }
320 
321 ScheduleDAGInstrs *
322 ARMBaseTargetMachine::createPostMachineScheduler(MachineSchedContext *C) const {
323   ScheduleDAGMI *DAG = createSchedPostRA(C);
324   // add DAG Mutations here.
325   const ARMSubtarget &ST = C->MF->getSubtarget<ARMSubtarget>();
326   if (ST.hasFusion())
327     DAG->addMutation(createARMMacroFusionDAGMutation());
328   if (auto Mutation = createARMLatencyMutations(ST, C->AA))
329     DAG->addMutation(std::move(Mutation));
330   return DAG;
331 }
332 
333 ARMLETargetMachine::ARMLETargetMachine(const Target &T, const Triple &TT,
334                                        StringRef CPU, StringRef FS,
335                                        const TargetOptions &Options,
336                                        std::optional<Reloc::Model> RM,
337                                        std::optional<CodeModel::Model> CM,
338                                        CodeGenOptLevel OL, bool JIT)
339     : ARMBaseTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, true) {}
340 
341 ARMBETargetMachine::ARMBETargetMachine(const Target &T, const Triple &TT,
342                                        StringRef CPU, StringRef FS,
343                                        const TargetOptions &Options,
344                                        std::optional<Reloc::Model> RM,
345                                        std::optional<CodeModel::Model> CM,
346                                        CodeGenOptLevel OL, bool JIT)
347     : ARMBaseTargetMachine(T, TT, CPU, FS, Options, RM, CM, OL, false) {}
348 
349 namespace {
350 
351 /// ARM Code Generator Pass Configuration Options.
352 class ARMPassConfig : public TargetPassConfig {
353 public:
354   ARMPassConfig(ARMBaseTargetMachine &TM, PassManagerBase &PM)
355       : TargetPassConfig(TM, PM) {}
356 
357   ARMBaseTargetMachine &getARMTargetMachine() const {
358     return getTM<ARMBaseTargetMachine>();
359   }
360 
361   void addIRPasses() override;
362   void addCodeGenPrepare() override;
363   bool addPreISel() override;
364   bool addInstSelector() override;
365   bool addIRTranslator() override;
366   bool addLegalizeMachineIR() override;
367   bool addRegBankSelect() override;
368   bool addGlobalInstructionSelect() override;
369   void addPreRegAlloc() override;
370   void addPreSched2() override;
371   void addPreEmitPass() override;
372   void addPreEmitPass2() override;
373 
374   std::unique_ptr<CSEConfigBase> getCSEConfig() const override;
375 };
376 
377 class ARMExecutionDomainFix : public ExecutionDomainFix {
378 public:
379   static char ID;
380   ARMExecutionDomainFix() : ExecutionDomainFix(ID, ARM::DPRRegClass) {}
381   StringRef getPassName() const override {
382     return "ARM Execution Domain Fix";
383   }
384 };
385 char ARMExecutionDomainFix::ID;
386 
387 } // end anonymous namespace
388 
389 INITIALIZE_PASS_BEGIN(ARMExecutionDomainFix, "arm-execution-domain-fix",
390   "ARM Execution Domain Fix", false, false)
391 INITIALIZE_PASS_DEPENDENCY(ReachingDefAnalysis)
392 INITIALIZE_PASS_END(ARMExecutionDomainFix, "arm-execution-domain-fix",
393   "ARM Execution Domain Fix", false, false)
394 
395 TargetPassConfig *ARMBaseTargetMachine::createPassConfig(PassManagerBase &PM) {
396   return new ARMPassConfig(*this, PM);
397 }
398 
399 std::unique_ptr<CSEConfigBase> ARMPassConfig::getCSEConfig() const {
400   return getStandardCSEConfigForOpt(TM->getOptLevel());
401 }
402 
403 void ARMPassConfig::addIRPasses() {
404   if (TM->Options.ThreadModel == ThreadModel::Single)
405     addPass(createLowerAtomicPass());
406   else
407     addPass(createAtomicExpandLegacyPass());
408 
409   // Cmpxchg instructions are often used with a subsequent comparison to
410   // determine whether it succeeded. We can exploit existing control-flow in
411   // ldrex/strex loops to simplify this, but it needs tidying up.
412   if (TM->getOptLevel() != CodeGenOptLevel::None && EnableAtomicTidy)
413     addPass(createCFGSimplificationPass(
414         SimplifyCFGOptions().hoistCommonInsts(true).sinkCommonInsts(true),
415         [this](const Function &F) {
416           const auto &ST = this->TM->getSubtarget<ARMSubtarget>(F);
417           return ST.hasAnyDataBarrier() && !ST.isThumb1Only();
418         }));
419 
420   addPass(createMVEGatherScatterLoweringPass());
421   addPass(createMVELaneInterleavingPass());
422 
423   TargetPassConfig::addIRPasses();
424 
425   // Run the parallel DSP pass.
426   if (getOptLevel() == CodeGenOptLevel::Aggressive)
427     addPass(createARMParallelDSPPass());
428 
429   // Match complex arithmetic patterns
430   if (TM->getOptLevel() >= CodeGenOptLevel::Default)
431     addPass(createComplexDeinterleavingPass(TM));
432 
433   // Match interleaved memory accesses to ldN/stN intrinsics.
434   if (TM->getOptLevel() != CodeGenOptLevel::None)
435     addPass(createInterleavedAccessPass());
436 
437   // Add Control Flow Guard checks.
438   if (TM->getTargetTriple().isOSWindows())
439     addPass(createCFGuardCheckPass());
440 
441   if (TM->Options.JMCInstrument)
442     addPass(createJMCInstrumenterPass());
443 }
444 
445 void ARMPassConfig::addCodeGenPrepare() {
446   if (getOptLevel() != CodeGenOptLevel::None)
447     addPass(createTypePromotionLegacyPass());
448   TargetPassConfig::addCodeGenPrepare();
449 }
450 
451 bool ARMPassConfig::addPreISel() {
452   if ((TM->getOptLevel() != CodeGenOptLevel::None &&
453        EnableGlobalMerge == cl::BOU_UNSET) ||
454       EnableGlobalMerge == cl::BOU_TRUE) {
455     // FIXME: This is using the thumb1 only constant value for
456     // maximal global offset for merging globals. We may want
457     // to look into using the old value for non-thumb1 code of
458     // 4095 based on the TargetMachine, but this starts to become
459     // tricky when doing code gen per function.
460     bool OnlyOptimizeForSize =
461         (TM->getOptLevel() < CodeGenOptLevel::Aggressive) &&
462         (EnableGlobalMerge == cl::BOU_UNSET);
463     // Merging of extern globals is enabled by default on non-Mach-O as we
464     // expect it to be generally either beneficial or harmless. On Mach-O it
465     // is disabled as we emit the .subsections_via_symbols directive which
466     // means that merging extern globals is not safe.
467     bool MergeExternalByDefault = !TM->getTargetTriple().isOSBinFormatMachO();
468     addPass(createGlobalMergePass(TM, 127, OnlyOptimizeForSize,
469                                   MergeExternalByDefault));
470   }
471 
472   if (TM->getOptLevel() != CodeGenOptLevel::None) {
473     addPass(createHardwareLoopsLegacyPass());
474     addPass(createMVETailPredicationPass());
475     // FIXME: IR passes can delete address-taken basic blocks, deleting
476     // corresponding blockaddresses. ARMConstantPoolConstant holds references to
477     // address-taken basic blocks which can be invalidated if the function
478     // containing the blockaddress has already been codegen'd and the basic
479     // block is removed. Work around this by forcing all IR passes to run before
480     // any ISel takes place. We should have a more principled way of handling
481     // this. See D99707 for more details.
482     addPass(createBarrierNoopPass());
483   }
484 
485   return false;
486 }
487 
488 bool ARMPassConfig::addInstSelector() {
489   addPass(createARMISelDag(getARMTargetMachine(), getOptLevel()));
490   return false;
491 }
492 
493 bool ARMPassConfig::addIRTranslator() {
494   addPass(new IRTranslator(getOptLevel()));
495   return false;
496 }
497 
498 bool ARMPassConfig::addLegalizeMachineIR() {
499   addPass(new Legalizer());
500   return false;
501 }
502 
503 bool ARMPassConfig::addRegBankSelect() {
504   addPass(new RegBankSelect());
505   return false;
506 }
507 
508 bool ARMPassConfig::addGlobalInstructionSelect() {
509   addPass(new InstructionSelect(getOptLevel()));
510   return false;
511 }
512 
513 void ARMPassConfig::addPreRegAlloc() {
514   if (getOptLevel() != CodeGenOptLevel::None) {
515     if (getOptLevel() == CodeGenOptLevel::Aggressive)
516       addPass(&MachinePipelinerID);
517 
518     addPass(createMVETPAndVPTOptimisationsPass());
519 
520     addPass(createMLxExpansionPass());
521 
522     if (EnableARMLoadStoreOpt)
523       addPass(createARMLoadStoreOptimizationPass(/* pre-register alloc */ true));
524 
525     if (!DisableA15SDOptimization)
526       addPass(createA15SDOptimizerPass());
527   }
528 }
529 
530 void ARMPassConfig::addPreSched2() {
531   if (getOptLevel() != CodeGenOptLevel::None) {
532     if (EnableARMLoadStoreOpt)
533       addPass(createARMLoadStoreOptimizationPass());
534 
535     addPass(new ARMExecutionDomainFix());
536     addPass(createBreakFalseDeps());
537   }
538 
539   // Expand some pseudo instructions into multiple instructions to allow
540   // proper scheduling.
541   addPass(createARMExpandPseudoPass());
542 
543   if (getOptLevel() != CodeGenOptLevel::None) {
544     // When optimising for size, always run the Thumb2SizeReduction pass before
545     // IfConversion. Otherwise, check whether IT blocks are restricted
546     // (e.g. in v8, IfConversion depends on Thumb instruction widths)
547     addPass(createThumb2SizeReductionPass([this](const Function &F) {
548       return this->TM->getSubtarget<ARMSubtarget>(F).hasMinSize() ||
549              this->TM->getSubtarget<ARMSubtarget>(F).restrictIT();
550     }));
551 
552     addPass(createIfConverter([](const MachineFunction &MF) {
553       return !MF.getSubtarget<ARMSubtarget>().isThumb1Only();
554     }));
555   }
556   addPass(createThumb2ITBlockPass());
557 
558   // Add both scheduling passes to give the subtarget an opportunity to pick
559   // between them.
560   if (getOptLevel() != CodeGenOptLevel::None) {
561     addPass(&PostMachineSchedulerID);
562     addPass(&PostRASchedulerID);
563   }
564 
565   addPass(createMVEVPTBlockPass());
566   addPass(createARMIndirectThunks());
567   addPass(createARMSLSHardeningPass());
568 }
569 
570 void ARMPassConfig::addPreEmitPass() {
571   addPass(createThumb2SizeReductionPass());
572 
573   // Constant island pass work on unbundled instructions.
574   addPass(createUnpackMachineBundles([](const MachineFunction &MF) {
575     return MF.getSubtarget<ARMSubtarget>().isThumb2();
576   }));
577 
578   // Don't optimize barriers or block placement at -O0.
579   if (getOptLevel() != CodeGenOptLevel::None) {
580     addPass(createARMBlockPlacementPass());
581     addPass(createARMOptimizeBarriersPass());
582   }
583 }
584 
585 void ARMPassConfig::addPreEmitPass2() {
586   // Inserts fixup instructions before unsafe AES operations. Instructions may
587   // be inserted at the start of blocks and at within blocks so this pass has to
588   // come before those below.
589   addPass(createARMFixCortexA57AES1742098Pass());
590   // Inserts BTIs at the start of functions and indirectly-called basic blocks,
591   // so passes cannot add to the start of basic blocks once this has run.
592   addPass(createARMBranchTargetsPass());
593   // Inserts Constant Islands. Block sizes cannot be increased after this point,
594   // as this may push the branch ranges and load offsets of accessing constant
595   // pools out of range..
596   addPass(createARMConstantIslandPass());
597   // Finalises Low-Overhead Loops. This replaces pseudo instructions with real
598   // instructions, but the pseudos all have conservative sizes so that block
599   // sizes will only be decreased by this pass.
600   addPass(createARMLowOverheadLoopsPass());
601 
602   if (TM->getTargetTriple().isOSWindows()) {
603     // Identify valid longjmp targets for Windows Control Flow Guard.
604     addPass(createCFGuardLongjmpPass());
605     // Identify valid eh continuation targets for Windows EHCont Guard.
606     addPass(createEHContGuardTargetsPass());
607   }
608 }
609 
610 yaml::MachineFunctionInfo *
611 ARMBaseTargetMachine::createDefaultFuncInfoYAML() const {
612   return new yaml::ARMFunctionInfo();
613 }
614 
615 yaml::MachineFunctionInfo *
616 ARMBaseTargetMachine::convertFuncInfoToYAML(const MachineFunction &MF) const {
617   const auto *MFI = MF.getInfo<ARMFunctionInfo>();
618   return new yaml::ARMFunctionInfo(*MFI);
619 }
620 
621 bool ARMBaseTargetMachine::parseMachineFunctionInfo(
622     const yaml::MachineFunctionInfo &MFI, PerFunctionMIParsingState &PFS,
623     SMDiagnostic &Error, SMRange &SourceRange) const {
624   const auto &YamlMFI = static_cast<const yaml::ARMFunctionInfo &>(MFI);
625   MachineFunction &MF = PFS.MF;
626   MF.getInfo<ARMFunctionInfo>()->initializeBaseYamlFields(YamlMFI);
627   return false;
628 }
629 
630 void ARMBaseTargetMachine::reset() { SubtargetMap.clear(); }
631