1 //===-- CommandFlags.cpp - Command Line Flags Interface ---------*- C++ -*-===//
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 // This file contains codegen-specific flags that are shared between different
10 // command line tools. The tools "llc" and "opt" both use this file to prevent
11 // flag duplication.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/CodeGen/CommandFlags.h"
16 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/ADT/Triple.h"
18 #include "llvm/IR/Instructions.h"
19 #include "llvm/IR/Intrinsics.h"
20 #include "llvm/IR/Module.h"
21 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
22 #include "llvm/MC/SubtargetFeature.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/Host.h"
25 #include "llvm/Support/MemoryBuffer.h"
26 
27 using namespace llvm;
28 
29 #define CGOPT(TY, NAME)                                                        \
30   static cl::opt<TY> *NAME##View;                                              \
31   TY codegen::get##NAME() {                                                    \
32     assert(NAME##View && "RegisterCodeGenFlags not created.");                 \
33     return *NAME##View;                                                        \
34   }
35 
36 #define CGLIST(TY, NAME)                                                       \
37   static cl::list<TY> *NAME##View;                                             \
38   std::vector<TY> codegen::get##NAME() {                                       \
39     assert(NAME##View && "RegisterCodeGenFlags not created.");                 \
40     return *NAME##View;                                                        \
41   }
42 
43 #define CGOPT_EXP(TY, NAME)                                                    \
44   CGOPT(TY, NAME)                                                              \
45   Optional<TY> codegen::getExplicit##NAME() {                                  \
46     if (NAME##View->getNumOccurrences()) {                                     \
47       TY res = *NAME##View;                                                    \
48       return res;                                                              \
49     }                                                                          \
50     return None;                                                               \
51   }
52 
53 CGOPT(std::string, MArch)
54 CGOPT(std::string, MCPU)
55 CGLIST(std::string, MAttrs)
56 CGOPT_EXP(Reloc::Model, RelocModel)
57 CGOPT(ThreadModel::Model, ThreadModel)
58 CGOPT_EXP(CodeModel::Model, CodeModel)
59 CGOPT(ExceptionHandling, ExceptionModel)
60 CGOPT_EXP(CodeGenFileType, FileType)
61 CGOPT(FramePointerKind, FramePointerUsage)
62 CGOPT(bool, EnableUnsafeFPMath)
63 CGOPT(bool, EnableNoInfsFPMath)
64 CGOPT(bool, EnableNoNaNsFPMath)
65 CGOPT(bool, EnableNoSignedZerosFPMath)
66 CGOPT(bool, EnableApproxFuncFPMath)
67 CGOPT(bool, EnableNoTrappingFPMath)
68 CGOPT(bool, EnableAIXExtendedAltivecABI)
69 CGOPT(DenormalMode::DenormalModeKind, DenormalFPMath)
70 CGOPT(DenormalMode::DenormalModeKind, DenormalFP32Math)
71 CGOPT(bool, EnableHonorSignDependentRoundingFPMath)
72 CGOPT(FloatABI::ABIType, FloatABIForCalls)
73 CGOPT(FPOpFusion::FPOpFusionMode, FuseFPOps)
74 CGOPT(SwiftAsyncFramePointerMode, SwiftAsyncFramePointer)
75 CGOPT(bool, DontPlaceZerosInBSS)
76 CGOPT(bool, EnableGuaranteedTailCallOpt)
77 CGOPT(bool, DisableTailCalls)
78 CGOPT(bool, StackSymbolOrdering)
79 CGOPT(bool, StackRealign)
80 CGOPT(std::string, TrapFuncName)
81 CGOPT(bool, UseCtors)
82 CGOPT(bool, LowerGlobalDtorsViaCxaAtExit)
83 CGOPT(bool, RelaxELFRelocations)
84 CGOPT_EXP(bool, DataSections)
85 CGOPT_EXP(bool, FunctionSections)
86 CGOPT(bool, IgnoreXCOFFVisibility)
87 CGOPT(bool, XCOFFTracebackTable)
88 CGOPT(std::string, BBSections)
89 CGOPT(unsigned, TLSSize)
90 CGOPT(bool, EmulatedTLS)
91 CGOPT(bool, UniqueSectionNames)
92 CGOPT(bool, UniqueBasicBlockSectionNames)
93 CGOPT(EABI, EABIVersion)
94 CGOPT(DebuggerKind, DebuggerTuningOpt)
95 CGOPT(bool, EnableStackSizeSection)
96 CGOPT(bool, EnableAddrsig)
97 CGOPT(bool, EmitCallSiteInfo)
98 CGOPT(bool, EnableMachineFunctionSplitter)
99 CGOPT(bool, EnableDebugEntryValues)
100 CGOPT(bool, ForceDwarfFrameSection)
101 CGOPT(bool, XRayOmitFunctionIndex)
102 CGOPT(bool, DebugStrictDwarf)
103 CGOPT(unsigned, AlignLoops)
104 CGOPT(bool, JMCInstrument)
105 
106 codegen::RegisterCodeGenFlags::RegisterCodeGenFlags() {
107 #define CGBINDOPT(NAME)                                                        \
108   do {                                                                         \
109     NAME##View = std::addressof(NAME);                                         \
110   } while (0)
111 
112   static cl::opt<std::string> MArch(
113       "march", cl::desc("Architecture to generate code for (see --version)"));
114   CGBINDOPT(MArch);
115 
116   static cl::opt<std::string> MCPU(
117       "mcpu", cl::desc("Target a specific cpu type (-mcpu=help for details)"),
118       cl::value_desc("cpu-name"), cl::init(""));
119   CGBINDOPT(MCPU);
120 
121   static cl::list<std::string> MAttrs(
122       "mattr", cl::CommaSeparated,
123       cl::desc("Target specific attributes (-mattr=help for details)"),
124       cl::value_desc("a1,+a2,-a3,..."));
125   CGBINDOPT(MAttrs);
126 
127   static cl::opt<Reloc::Model> RelocModel(
128       "relocation-model", cl::desc("Choose relocation model"),
129       cl::values(
130           clEnumValN(Reloc::Static, "static", "Non-relocatable code"),
131           clEnumValN(Reloc::PIC_, "pic",
132                      "Fully relocatable, position independent code"),
133           clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
134                      "Relocatable external references, non-relocatable code"),
135           clEnumValN(
136               Reloc::ROPI, "ropi",
137               "Code and read-only data relocatable, accessed PC-relative"),
138           clEnumValN(
139               Reloc::RWPI, "rwpi",
140               "Read-write data relocatable, accessed relative to static base"),
141           clEnumValN(Reloc::ROPI_RWPI, "ropi-rwpi",
142                      "Combination of ropi and rwpi")));
143   CGBINDOPT(RelocModel);
144 
145   static cl::opt<ThreadModel::Model> ThreadModel(
146       "thread-model", cl::desc("Choose threading model"),
147       cl::init(ThreadModel::POSIX),
148       cl::values(
149           clEnumValN(ThreadModel::POSIX, "posix", "POSIX thread model"),
150           clEnumValN(ThreadModel::Single, "single", "Single thread model")));
151   CGBINDOPT(ThreadModel);
152 
153   static cl::opt<CodeModel::Model> CodeModel(
154       "code-model", cl::desc("Choose code model"),
155       cl::values(clEnumValN(CodeModel::Tiny, "tiny", "Tiny code model"),
156                  clEnumValN(CodeModel::Small, "small", "Small code model"),
157                  clEnumValN(CodeModel::Kernel, "kernel", "Kernel code model"),
158                  clEnumValN(CodeModel::Medium, "medium", "Medium code model"),
159                  clEnumValN(CodeModel::Large, "large", "Large code model")));
160   CGBINDOPT(CodeModel);
161 
162   static cl::opt<ExceptionHandling> ExceptionModel(
163       "exception-model", cl::desc("exception model"),
164       cl::init(ExceptionHandling::None),
165       cl::values(
166           clEnumValN(ExceptionHandling::None, "default",
167                      "default exception handling model"),
168           clEnumValN(ExceptionHandling::DwarfCFI, "dwarf",
169                      "DWARF-like CFI based exception handling"),
170           clEnumValN(ExceptionHandling::SjLj, "sjlj",
171                      "SjLj exception handling"),
172           clEnumValN(ExceptionHandling::ARM, "arm", "ARM EHABI exceptions"),
173           clEnumValN(ExceptionHandling::WinEH, "wineh",
174                      "Windows exception model"),
175           clEnumValN(ExceptionHandling::Wasm, "wasm",
176                      "WebAssembly exception handling")));
177   CGBINDOPT(ExceptionModel);
178 
179   static cl::opt<CodeGenFileType> FileType(
180       "filetype", cl::init(CGFT_AssemblyFile),
181       cl::desc(
182           "Choose a file type (not all types are supported by all targets):"),
183       cl::values(
184           clEnumValN(CGFT_AssemblyFile, "asm", "Emit an assembly ('.s') file"),
185           clEnumValN(CGFT_ObjectFile, "obj",
186                      "Emit a native object ('.o') file"),
187           clEnumValN(CGFT_Null, "null",
188                      "Emit nothing, for performance testing")));
189   CGBINDOPT(FileType);
190 
191   static cl::opt<FramePointerKind> FramePointerUsage(
192       "frame-pointer",
193       cl::desc("Specify frame pointer elimination optimization"),
194       cl::init(FramePointerKind::None),
195       cl::values(
196           clEnumValN(FramePointerKind::All, "all",
197                      "Disable frame pointer elimination"),
198           clEnumValN(FramePointerKind::NonLeaf, "non-leaf",
199                      "Disable frame pointer elimination for non-leaf frame"),
200           clEnumValN(FramePointerKind::None, "none",
201                      "Enable frame pointer elimination")));
202   CGBINDOPT(FramePointerUsage);
203 
204   static cl::opt<bool> EnableUnsafeFPMath(
205       "enable-unsafe-fp-math",
206       cl::desc("Enable optimizations that may decrease FP precision"),
207       cl::init(false));
208   CGBINDOPT(EnableUnsafeFPMath);
209 
210   static cl::opt<bool> EnableNoInfsFPMath(
211       "enable-no-infs-fp-math",
212       cl::desc("Enable FP math optimizations that assume no +-Infs"),
213       cl::init(false));
214   CGBINDOPT(EnableNoInfsFPMath);
215 
216   static cl::opt<bool> EnableNoNaNsFPMath(
217       "enable-no-nans-fp-math",
218       cl::desc("Enable FP math optimizations that assume no NaNs"),
219       cl::init(false));
220   CGBINDOPT(EnableNoNaNsFPMath);
221 
222   static cl::opt<bool> EnableNoSignedZerosFPMath(
223       "enable-no-signed-zeros-fp-math",
224       cl::desc("Enable FP math optimizations that assume "
225                "the sign of 0 is insignificant"),
226       cl::init(false));
227   CGBINDOPT(EnableNoSignedZerosFPMath);
228 
229   static cl::opt<bool> EnableApproxFuncFPMath(
230       "enable-approx-func-fp-math",
231       cl::desc("Enable FP math optimizations that assume approx func"),
232       cl::init(false));
233   CGBINDOPT(EnableApproxFuncFPMath);
234 
235   static cl::opt<bool> EnableNoTrappingFPMath(
236       "enable-no-trapping-fp-math",
237       cl::desc("Enable setting the FP exceptions build "
238                "attribute not to use exceptions"),
239       cl::init(false));
240   CGBINDOPT(EnableNoTrappingFPMath);
241 
242   static const auto DenormFlagEnumOptions =
243   cl::values(clEnumValN(DenormalMode::IEEE, "ieee",
244                         "IEEE 754 denormal numbers"),
245              clEnumValN(DenormalMode::PreserveSign, "preserve-sign",
246                         "the sign of a  flushed-to-zero number is preserved "
247                         "in the sign of 0"),
248              clEnumValN(DenormalMode::PositiveZero, "positive-zero",
249                         "denormals are flushed to positive zero"));
250 
251   // FIXME: Doesn't have way to specify separate input and output modes.
252   static cl::opt<DenormalMode::DenormalModeKind> DenormalFPMath(
253     "denormal-fp-math",
254     cl::desc("Select which denormal numbers the code is permitted to require"),
255     cl::init(DenormalMode::IEEE),
256     DenormFlagEnumOptions);
257   CGBINDOPT(DenormalFPMath);
258 
259   static cl::opt<DenormalMode::DenormalModeKind> DenormalFP32Math(
260     "denormal-fp-math-f32",
261     cl::desc("Select which denormal numbers the code is permitted to require for float"),
262     cl::init(DenormalMode::Invalid),
263     DenormFlagEnumOptions);
264   CGBINDOPT(DenormalFP32Math);
265 
266   static cl::opt<bool> EnableHonorSignDependentRoundingFPMath(
267       "enable-sign-dependent-rounding-fp-math", cl::Hidden,
268       cl::desc("Force codegen to assume rounding mode can change dynamically"),
269       cl::init(false));
270   CGBINDOPT(EnableHonorSignDependentRoundingFPMath);
271 
272   static cl::opt<FloatABI::ABIType> FloatABIForCalls(
273       "float-abi", cl::desc("Choose float ABI type"),
274       cl::init(FloatABI::Default),
275       cl::values(clEnumValN(FloatABI::Default, "default",
276                             "Target default float ABI type"),
277                  clEnumValN(FloatABI::Soft, "soft",
278                             "Soft float ABI (implied by -soft-float)"),
279                  clEnumValN(FloatABI::Hard, "hard",
280                             "Hard float ABI (uses FP registers)")));
281   CGBINDOPT(FloatABIForCalls);
282 
283   static cl::opt<FPOpFusion::FPOpFusionMode> FuseFPOps(
284       "fp-contract", cl::desc("Enable aggressive formation of fused FP ops"),
285       cl::init(FPOpFusion::Standard),
286       cl::values(
287           clEnumValN(FPOpFusion::Fast, "fast",
288                      "Fuse FP ops whenever profitable"),
289           clEnumValN(FPOpFusion::Standard, "on", "Only fuse 'blessed' FP ops."),
290           clEnumValN(FPOpFusion::Strict, "off",
291                      "Only fuse FP ops when the result won't be affected.")));
292   CGBINDOPT(FuseFPOps);
293 
294   static cl::opt<SwiftAsyncFramePointerMode> SwiftAsyncFramePointer(
295       "swift-async-fp",
296       cl::desc("Determine when the Swift async frame pointer should be set"),
297       cl::init(SwiftAsyncFramePointerMode::Always),
298       cl::values(clEnumValN(SwiftAsyncFramePointerMode::DeploymentBased, "auto",
299                             "Determine based on deployment target"),
300                  clEnumValN(SwiftAsyncFramePointerMode::Always, "always",
301                             "Always set the bit"),
302                  clEnumValN(SwiftAsyncFramePointerMode::Never, "never",
303                             "Never set the bit")));
304   CGBINDOPT(SwiftAsyncFramePointer);
305 
306   static cl::opt<bool> DontPlaceZerosInBSS(
307       "nozero-initialized-in-bss",
308       cl::desc("Don't place zero-initialized symbols into bss section"),
309       cl::init(false));
310   CGBINDOPT(DontPlaceZerosInBSS);
311 
312   static cl::opt<bool> EnableAIXExtendedAltivecABI(
313       "vec-extabi", cl::desc("Enable the AIX Extended Altivec ABI."),
314       cl::init(false));
315   CGBINDOPT(EnableAIXExtendedAltivecABI);
316 
317   static cl::opt<bool> EnableGuaranteedTailCallOpt(
318       "tailcallopt",
319       cl::desc(
320           "Turn fastcc calls into tail calls by (potentially) changing ABI."),
321       cl::init(false));
322   CGBINDOPT(EnableGuaranteedTailCallOpt);
323 
324   static cl::opt<bool> DisableTailCalls(
325       "disable-tail-calls", cl::desc("Never emit tail calls"), cl::init(false));
326   CGBINDOPT(DisableTailCalls);
327 
328   static cl::opt<bool> StackSymbolOrdering(
329       "stack-symbol-ordering", cl::desc("Order local stack symbols."),
330       cl::init(true));
331   CGBINDOPT(StackSymbolOrdering);
332 
333   static cl::opt<bool> StackRealign(
334       "stackrealign",
335       cl::desc("Force align the stack to the minimum alignment"),
336       cl::init(false));
337   CGBINDOPT(StackRealign);
338 
339   static cl::opt<std::string> TrapFuncName(
340       "trap-func", cl::Hidden,
341       cl::desc("Emit a call to trap function rather than a trap instruction"),
342       cl::init(""));
343   CGBINDOPT(TrapFuncName);
344 
345   static cl::opt<bool> UseCtors("use-ctors",
346                                 cl::desc("Use .ctors instead of .init_array."),
347                                 cl::init(false));
348   CGBINDOPT(UseCtors);
349 
350   static cl::opt<bool> LowerGlobalDtorsViaCxaAtExit(
351       "lower-global-dtors-via-cxa-atexit",
352       cl::desc("Lower llvm.global_dtors (global destructors) via __cxa_atexit"),
353       cl::init(true));
354   CGBINDOPT(LowerGlobalDtorsViaCxaAtExit);
355 
356   static cl::opt<bool> RelaxELFRelocations(
357       "relax-elf-relocations",
358       cl::desc(
359           "Emit GOTPCRELX/REX_GOTPCRELX instead of GOTPCREL on x86-64 ELF"),
360       cl::init(false));
361   CGBINDOPT(RelaxELFRelocations);
362 
363   static cl::opt<bool> DataSections(
364       "data-sections", cl::desc("Emit data into separate sections"),
365       cl::init(false));
366   CGBINDOPT(DataSections);
367 
368   static cl::opt<bool> FunctionSections(
369       "function-sections", cl::desc("Emit functions into separate sections"),
370       cl::init(false));
371   CGBINDOPT(FunctionSections);
372 
373   static cl::opt<bool> IgnoreXCOFFVisibility(
374       "ignore-xcoff-visibility",
375       cl::desc("Not emit the visibility attribute for asm in AIX OS or give "
376                "all symbols 'unspecified' visibility in XCOFF object file"),
377       cl::init(false));
378   CGBINDOPT(IgnoreXCOFFVisibility);
379 
380   static cl::opt<bool> XCOFFTracebackTable(
381       "xcoff-traceback-table", cl::desc("Emit the XCOFF traceback table"),
382       cl::init(true));
383   CGBINDOPT(XCOFFTracebackTable);
384 
385   static cl::opt<std::string> BBSections(
386       "basic-block-sections",
387       cl::desc("Emit basic blocks into separate sections"),
388       cl::value_desc("all | <function list (file)> | labels | none"),
389       cl::init("none"));
390   CGBINDOPT(BBSections);
391 
392   static cl::opt<unsigned> TLSSize(
393       "tls-size", cl::desc("Bit size of immediate TLS offsets"), cl::init(0));
394   CGBINDOPT(TLSSize);
395 
396   static cl::opt<bool> EmulatedTLS(
397       "emulated-tls", cl::desc("Use emulated TLS model"), cl::init(false));
398   CGBINDOPT(EmulatedTLS);
399 
400   static cl::opt<bool> UniqueSectionNames(
401       "unique-section-names", cl::desc("Give unique names to every section"),
402       cl::init(true));
403   CGBINDOPT(UniqueSectionNames);
404 
405   static cl::opt<bool> UniqueBasicBlockSectionNames(
406       "unique-basic-block-section-names",
407       cl::desc("Give unique names to every basic block section"),
408       cl::init(false));
409   CGBINDOPT(UniqueBasicBlockSectionNames);
410 
411   static cl::opt<EABI> EABIVersion(
412       "meabi", cl::desc("Set EABI type (default depends on triple):"),
413       cl::init(EABI::Default),
414       cl::values(
415           clEnumValN(EABI::Default, "default", "Triple default EABI version"),
416           clEnumValN(EABI::EABI4, "4", "EABI version 4"),
417           clEnumValN(EABI::EABI5, "5", "EABI version 5"),
418           clEnumValN(EABI::GNU, "gnu", "EABI GNU")));
419   CGBINDOPT(EABIVersion);
420 
421   static cl::opt<DebuggerKind> DebuggerTuningOpt(
422       "debugger-tune", cl::desc("Tune debug info for a particular debugger"),
423       cl::init(DebuggerKind::Default),
424       cl::values(
425           clEnumValN(DebuggerKind::GDB, "gdb", "gdb"),
426           clEnumValN(DebuggerKind::LLDB, "lldb", "lldb"),
427           clEnumValN(DebuggerKind::DBX, "dbx", "dbx"),
428           clEnumValN(DebuggerKind::SCE, "sce", "SCE targets (e.g. PS4)")));
429   CGBINDOPT(DebuggerTuningOpt);
430 
431   static cl::opt<bool> EnableStackSizeSection(
432       "stack-size-section",
433       cl::desc("Emit a section containing stack size metadata"),
434       cl::init(false));
435   CGBINDOPT(EnableStackSizeSection);
436 
437   static cl::opt<bool> EnableAddrsig(
438       "addrsig", cl::desc("Emit an address-significance table"),
439       cl::init(false));
440   CGBINDOPT(EnableAddrsig);
441 
442   static cl::opt<bool> EmitCallSiteInfo(
443       "emit-call-site-info",
444       cl::desc(
445           "Emit call site debug information, if debug information is enabled."),
446       cl::init(false));
447   CGBINDOPT(EmitCallSiteInfo);
448 
449   static cl::opt<bool> EnableDebugEntryValues(
450       "debug-entry-values",
451       cl::desc("Enable debug info for the debug entry values."),
452       cl::init(false));
453   CGBINDOPT(EnableDebugEntryValues);
454 
455   static cl::opt<bool> EnableMachineFunctionSplitter(
456       "split-machine-functions",
457       cl::desc("Split out cold basic blocks from machine functions based on "
458                "profile information"),
459       cl::init(false));
460   CGBINDOPT(EnableMachineFunctionSplitter);
461 
462   static cl::opt<bool> ForceDwarfFrameSection(
463       "force-dwarf-frame-section",
464       cl::desc("Always emit a debug frame section."), cl::init(false));
465   CGBINDOPT(ForceDwarfFrameSection);
466 
467   static cl::opt<bool> XRayOmitFunctionIndex(
468       "no-xray-index", cl::desc("Don't emit xray_fn_idx section"),
469       cl::init(false));
470   CGBINDOPT(XRayOmitFunctionIndex);
471 
472   static cl::opt<bool> DebugStrictDwarf(
473       "strict-dwarf", cl::desc("use strict dwarf"), cl::init(false));
474   CGBINDOPT(DebugStrictDwarf);
475 
476   static cl::opt<unsigned> AlignLoops("align-loops",
477                                       cl::desc("Default alignment for loops"));
478   CGBINDOPT(AlignLoops);
479 
480   static cl::opt<bool> JMCInstrument(
481       "enable-jmc-instrument",
482       cl::desc("Instrument functions with a call to __CheckForDebuggerJustMyCode"),
483       cl::init(false));
484   CGBINDOPT(JMCInstrument);
485 
486 #undef CGBINDOPT
487 
488   mc::RegisterMCTargetOptionsFlags();
489 }
490 
491 llvm::BasicBlockSection
492 codegen::getBBSectionsMode(llvm::TargetOptions &Options) {
493   if (getBBSections() == "all")
494     return BasicBlockSection::All;
495   else if (getBBSections() == "labels")
496     return BasicBlockSection::Labels;
497   else if (getBBSections() == "none")
498     return BasicBlockSection::None;
499   else {
500     ErrorOr<std::unique_ptr<MemoryBuffer>> MBOrErr =
501         MemoryBuffer::getFile(getBBSections());
502     if (!MBOrErr) {
503       errs() << "Error loading basic block sections function list file: "
504              << MBOrErr.getError().message() << "\n";
505     } else {
506       Options.BBSectionsFuncListBuf = std::move(*MBOrErr);
507     }
508     return BasicBlockSection::List;
509   }
510 }
511 
512 // Common utility function tightly tied to the options listed here. Initializes
513 // a TargetOptions object with CodeGen flags and returns it.
514 TargetOptions
515 codegen::InitTargetOptionsFromCodeGenFlags(const Triple &TheTriple) {
516   TargetOptions Options;
517   Options.AllowFPOpFusion = getFuseFPOps();
518   Options.UnsafeFPMath = getEnableUnsafeFPMath();
519   Options.NoInfsFPMath = getEnableNoInfsFPMath();
520   Options.NoNaNsFPMath = getEnableNoNaNsFPMath();
521   Options.NoSignedZerosFPMath = getEnableNoSignedZerosFPMath();
522   Options.ApproxFuncFPMath = getEnableApproxFuncFPMath();
523   Options.NoTrappingFPMath = getEnableNoTrappingFPMath();
524 
525   DenormalMode::DenormalModeKind DenormKind = getDenormalFPMath();
526 
527   // FIXME: Should have separate input and output flags
528   Options.setFPDenormalMode(DenormalMode(DenormKind, DenormKind));
529 
530   Options.HonorSignDependentRoundingFPMathOption =
531       getEnableHonorSignDependentRoundingFPMath();
532   if (getFloatABIForCalls() != FloatABI::Default)
533     Options.FloatABIType = getFloatABIForCalls();
534   Options.EnableAIXExtendedAltivecABI = getEnableAIXExtendedAltivecABI();
535   Options.NoZerosInBSS = getDontPlaceZerosInBSS();
536   Options.GuaranteedTailCallOpt = getEnableGuaranteedTailCallOpt();
537   Options.StackSymbolOrdering = getStackSymbolOrdering();
538   Options.UseInitArray = !getUseCtors();
539   Options.LowerGlobalDtorsViaCxaAtExit = getLowerGlobalDtorsViaCxaAtExit();
540   Options.RelaxELFRelocations = getRelaxELFRelocations();
541   Options.DataSections =
542       getExplicitDataSections().value_or(TheTriple.hasDefaultDataSections());
543   Options.FunctionSections = getFunctionSections();
544   Options.IgnoreXCOFFVisibility = getIgnoreXCOFFVisibility();
545   Options.XCOFFTracebackTable = getXCOFFTracebackTable();
546   Options.BBSections = getBBSectionsMode(Options);
547   Options.UniqueSectionNames = getUniqueSectionNames();
548   Options.UniqueBasicBlockSectionNames = getUniqueBasicBlockSectionNames();
549   Options.TLSSize = getTLSSize();
550   Options.EmulatedTLS = getEmulatedTLS();
551   Options.ExplicitEmulatedTLS = EmulatedTLSView->getNumOccurrences() > 0;
552   Options.ExceptionModel = getExceptionModel();
553   Options.EmitStackSizeSection = getEnableStackSizeSection();
554   Options.EnableMachineFunctionSplitter = getEnableMachineFunctionSplitter();
555   Options.EmitAddrsig = getEnableAddrsig();
556   Options.EmitCallSiteInfo = getEmitCallSiteInfo();
557   Options.EnableDebugEntryValues = getEnableDebugEntryValues();
558   Options.ForceDwarfFrameSection = getForceDwarfFrameSection();
559   Options.XRayOmitFunctionIndex = getXRayOmitFunctionIndex();
560   Options.DebugStrictDwarf = getDebugStrictDwarf();
561   Options.LoopAlignment = getAlignLoops();
562   Options.JMCInstrument = getJMCInstrument();
563 
564   Options.MCOptions = mc::InitMCTargetOptionsFromFlags();
565 
566   Options.ThreadModel = getThreadModel();
567   Options.EABIVersion = getEABIVersion();
568   Options.DebuggerTuning = getDebuggerTuningOpt();
569   Options.SwiftAsyncFramePointer = getSwiftAsyncFramePointer();
570   return Options;
571 }
572 
573 std::string codegen::getCPUStr() {
574   // If user asked for the 'native' CPU, autodetect here. If autodection fails,
575   // this will set the CPU to an empty string which tells the target to
576   // pick a basic default.
577   if (getMCPU() == "native")
578     return std::string(sys::getHostCPUName());
579 
580   return getMCPU();
581 }
582 
583 std::string codegen::getFeaturesStr() {
584   SubtargetFeatures Features;
585 
586   // If user asked for the 'native' CPU, we need to autodetect features.
587   // This is necessary for x86 where the CPU might not support all the
588   // features the autodetected CPU name lists in the target. For example,
589   // not all Sandybridge processors support AVX.
590   if (getMCPU() == "native") {
591     StringMap<bool> HostFeatures;
592     if (sys::getHostCPUFeatures(HostFeatures))
593       for (auto &F : HostFeatures)
594         Features.AddFeature(F.first(), F.second);
595   }
596 
597   for (auto const &MAttr : getMAttrs())
598     Features.AddFeature(MAttr);
599 
600   return Features.getString();
601 }
602 
603 std::vector<std::string> codegen::getFeatureList() {
604   SubtargetFeatures Features;
605 
606   // If user asked for the 'native' CPU, we need to autodetect features.
607   // This is necessary for x86 where the CPU might not support all the
608   // features the autodetected CPU name lists in the target. For example,
609   // not all Sandybridge processors support AVX.
610   if (getMCPU() == "native") {
611     StringMap<bool> HostFeatures;
612     if (sys::getHostCPUFeatures(HostFeatures))
613       for (auto &F : HostFeatures)
614         Features.AddFeature(F.first(), F.second);
615   }
616 
617   for (auto const &MAttr : getMAttrs())
618     Features.AddFeature(MAttr);
619 
620   return Features.getFeatures();
621 }
622 
623 void codegen::renderBoolStringAttr(AttrBuilder &B, StringRef Name, bool Val) {
624   B.addAttribute(Name, Val ? "true" : "false");
625 }
626 
627 #define HANDLE_BOOL_ATTR(CL, AttrName)                                         \
628   do {                                                                         \
629     if (CL->getNumOccurrences() > 0 && !F.hasFnAttribute(AttrName))            \
630       renderBoolStringAttr(NewAttrs, AttrName, *CL);                           \
631   } while (0)
632 
633 /// Set function attributes of function \p F based on CPU, Features, and command
634 /// line flags.
635 void codegen::setFunctionAttributes(StringRef CPU, StringRef Features,
636                                     Function &F) {
637   auto &Ctx = F.getContext();
638   AttributeList Attrs = F.getAttributes();
639   AttrBuilder NewAttrs(Ctx);
640 
641   if (!CPU.empty() && !F.hasFnAttribute("target-cpu"))
642     NewAttrs.addAttribute("target-cpu", CPU);
643   if (!Features.empty()) {
644     // Append the command line features to any that are already on the function.
645     StringRef OldFeatures =
646         F.getFnAttribute("target-features").getValueAsString();
647     if (OldFeatures.empty())
648       NewAttrs.addAttribute("target-features", Features);
649     else {
650       SmallString<256> Appended(OldFeatures);
651       Appended.push_back(',');
652       Appended.append(Features);
653       NewAttrs.addAttribute("target-features", Appended);
654     }
655   }
656   if (FramePointerUsageView->getNumOccurrences() > 0 &&
657       !F.hasFnAttribute("frame-pointer")) {
658     if (getFramePointerUsage() == FramePointerKind::All)
659       NewAttrs.addAttribute("frame-pointer", "all");
660     else if (getFramePointerUsage() == FramePointerKind::NonLeaf)
661       NewAttrs.addAttribute("frame-pointer", "non-leaf");
662     else if (getFramePointerUsage() == FramePointerKind::None)
663       NewAttrs.addAttribute("frame-pointer", "none");
664   }
665   if (DisableTailCallsView->getNumOccurrences() > 0)
666     NewAttrs.addAttribute("disable-tail-calls",
667                           toStringRef(getDisableTailCalls()));
668   if (getStackRealign())
669     NewAttrs.addAttribute("stackrealign");
670 
671   HANDLE_BOOL_ATTR(EnableUnsafeFPMathView, "unsafe-fp-math");
672   HANDLE_BOOL_ATTR(EnableNoInfsFPMathView, "no-infs-fp-math");
673   HANDLE_BOOL_ATTR(EnableNoNaNsFPMathView, "no-nans-fp-math");
674   HANDLE_BOOL_ATTR(EnableNoSignedZerosFPMathView, "no-signed-zeros-fp-math");
675   HANDLE_BOOL_ATTR(EnableApproxFuncFPMathView, "approx-func-fp-math");
676 
677   if (DenormalFPMathView->getNumOccurrences() > 0 &&
678       !F.hasFnAttribute("denormal-fp-math")) {
679     DenormalMode::DenormalModeKind DenormKind = getDenormalFPMath();
680 
681     // FIXME: Command line flag should expose separate input/output modes.
682     NewAttrs.addAttribute("denormal-fp-math",
683                           DenormalMode(DenormKind, DenormKind).str());
684   }
685 
686   if (DenormalFP32MathView->getNumOccurrences() > 0 &&
687       !F.hasFnAttribute("denormal-fp-math-f32")) {
688     // FIXME: Command line flag should expose separate input/output modes.
689     DenormalMode::DenormalModeKind DenormKind = getDenormalFP32Math();
690 
691     NewAttrs.addAttribute(
692       "denormal-fp-math-f32",
693       DenormalMode(DenormKind, DenormKind).str());
694   }
695 
696   if (TrapFuncNameView->getNumOccurrences() > 0)
697     for (auto &B : F)
698       for (auto &I : B)
699         if (auto *Call = dyn_cast<CallInst>(&I))
700           if (const auto *F = Call->getCalledFunction())
701             if (F->getIntrinsicID() == Intrinsic::debugtrap ||
702                 F->getIntrinsicID() == Intrinsic::trap)
703               Call->addFnAttr(
704                   Attribute::get(Ctx, "trap-func-name", getTrapFuncName()));
705 
706   // Let NewAttrs override Attrs.
707   F.setAttributes(Attrs.addFnAttributes(Ctx, NewAttrs));
708 }
709 
710 /// Set function attributes of functions in Module M based on CPU,
711 /// Features, and command line flags.
712 void codegen::setFunctionAttributes(StringRef CPU, StringRef Features,
713                                     Module &M) {
714   for (Function &F : M)
715     setFunctionAttributes(CPU, Features, F);
716 }
717