xref: /llvm-project/llvm/lib/CodeGen/CommandFlags.cpp (revision a1944386156dbbfae15dfc606a3728e08ac92cfe)
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/IR/Module.h"
17 #include "llvm/MC/SubtargetFeature.h"
18 #include "llvm/Support/CommandLine.h"
19 #include "llvm/Support/Host.h"
20 #include "llvm/Support/MemoryBuffer.h"
21 
22 using namespace llvm;
23 
24 #define CGOPT(TY, NAME)                                                        \
25   static cl::opt<TY> *NAME##View;                                              \
26   TY codegen::get##NAME() {                                                    \
27     assert(NAME##View && "RegisterCodeGenFlags not created.");                 \
28     return *NAME##View;                                                        \
29   }
30 
31 #define CGLIST(TY, NAME)                                                       \
32   static cl::list<TY> *NAME##View;                                             \
33   std::vector<TY> codegen::get##NAME() {                                       \
34     assert(NAME##View && "RegisterCodeGenFlags not created.");                 \
35     return *NAME##View;                                                        \
36   }
37 
38 #define CGOPT_EXP(TY, NAME)                                                    \
39   CGOPT(TY, NAME)                                                              \
40   Optional<TY> codegen::getExplicit##NAME() {                                  \
41     if (NAME##View->getNumOccurrences()) {                                     \
42       TY res = *NAME##View;                                                    \
43       return res;                                                              \
44     }                                                                          \
45     return None;                                                               \
46   }
47 
48 CGOPT(std::string, MArch)
49 CGOPT(std::string, MCPU)
50 CGLIST(std::string, MAttrs)
51 CGOPT_EXP(Reloc::Model, RelocModel)
52 CGOPT(ThreadModel::Model, ThreadModel)
53 CGOPT_EXP(CodeModel::Model, CodeModel)
54 CGOPT(ExceptionHandling, ExceptionModel)
55 CGOPT_EXP(CodeGenFileType, FileType)
56 CGOPT(FramePointerKind, FramePointerUsage)
57 CGOPT(bool, EnableUnsafeFPMath)
58 CGOPT(bool, EnableNoInfsFPMath)
59 CGOPT(bool, EnableNoNaNsFPMath)
60 CGOPT(bool, EnableNoSignedZerosFPMath)
61 CGOPT(bool, EnableNoTrappingFPMath)
62 CGOPT(bool, EnableAIXExtendedAltivecABI)
63 CGOPT(DenormalMode::DenormalModeKind, DenormalFPMath)
64 CGOPT(DenormalMode::DenormalModeKind, DenormalFP32Math)
65 CGOPT(bool, EnableHonorSignDependentRoundingFPMath)
66 CGOPT(FloatABI::ABIType, FloatABIForCalls)
67 CGOPT(FPOpFusion::FPOpFusionMode, FuseFPOps)
68 CGOPT(bool, DontPlaceZerosInBSS)
69 CGOPT(bool, EnableGuaranteedTailCallOpt)
70 CGOPT(bool, DisableTailCalls)
71 CGOPT(bool, StackSymbolOrdering)
72 CGOPT(bool, StackRealign)
73 CGOPT(std::string, TrapFuncName)
74 CGOPT(bool, UseCtors)
75 CGOPT(bool, RelaxELFRelocations)
76 CGOPT_EXP(bool, DataSections)
77 CGOPT_EXP(bool, FunctionSections)
78 CGOPT(bool, IgnoreXCOFFVisibility)
79 CGOPT(bool, XCOFFTracebackTable)
80 CGOPT(std::string, BBSections)
81 CGOPT(unsigned, TLSSize)
82 CGOPT(bool, EmulatedTLS)
83 CGOPT(bool, UniqueSectionNames)
84 CGOPT(bool, UniqueBasicBlockSectionNames)
85 CGOPT(EABI, EABIVersion)
86 CGOPT(DebuggerKind, DebuggerTuningOpt)
87 CGOPT(bool, EnableStackSizeSection)
88 CGOPT(bool, EnableAddrsig)
89 CGOPT(bool, EmitCallSiteInfo)
90 CGOPT(bool, EnableMachineFunctionSplitter)
91 CGOPT(bool, EnableDebugEntryValues)
92 CGOPT(bool, PseudoProbeForProfiling)
93 CGOPT(bool, ValueTrackingVariableLocations)
94 CGOPT(bool, ForceDwarfFrameSection)
95 CGOPT(bool, XRayOmitFunctionIndex)
96 CGOPT(bool, DebugStrictDwarf)
97 CGOPT(unsigned, AlignLoops)
98 
99 codegen::RegisterCodeGenFlags::RegisterCodeGenFlags() {
100 #define CGBINDOPT(NAME)                                                        \
101   do {                                                                         \
102     NAME##View = std::addressof(NAME);                                         \
103   } while (0)
104 
105   static cl::opt<std::string> MArch(
106       "march", cl::desc("Architecture to generate code for (see --version)"));
107   CGBINDOPT(MArch);
108 
109   static cl::opt<std::string> MCPU(
110       "mcpu", cl::desc("Target a specific cpu type (-mcpu=help for details)"),
111       cl::value_desc("cpu-name"), cl::init(""));
112   CGBINDOPT(MCPU);
113 
114   static cl::list<std::string> MAttrs(
115       "mattr", cl::CommaSeparated,
116       cl::desc("Target specific attributes (-mattr=help for details)"),
117       cl::value_desc("a1,+a2,-a3,..."));
118   CGBINDOPT(MAttrs);
119 
120   static cl::opt<Reloc::Model> RelocModel(
121       "relocation-model", cl::desc("Choose relocation model"),
122       cl::values(
123           clEnumValN(Reloc::Static, "static", "Non-relocatable code"),
124           clEnumValN(Reloc::PIC_, "pic",
125                      "Fully relocatable, position independent code"),
126           clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
127                      "Relocatable external references, non-relocatable code"),
128           clEnumValN(
129               Reloc::ROPI, "ropi",
130               "Code and read-only data relocatable, accessed PC-relative"),
131           clEnumValN(
132               Reloc::RWPI, "rwpi",
133               "Read-write data relocatable, accessed relative to static base"),
134           clEnumValN(Reloc::ROPI_RWPI, "ropi-rwpi",
135                      "Combination of ropi and rwpi")));
136   CGBINDOPT(RelocModel);
137 
138   static cl::opt<ThreadModel::Model> ThreadModel(
139       "thread-model", cl::desc("Choose threading model"),
140       cl::init(ThreadModel::POSIX),
141       cl::values(
142           clEnumValN(ThreadModel::POSIX, "posix", "POSIX thread model"),
143           clEnumValN(ThreadModel::Single, "single", "Single thread model")));
144   CGBINDOPT(ThreadModel);
145 
146   static cl::opt<CodeModel::Model> CodeModel(
147       "code-model", cl::desc("Choose code model"),
148       cl::values(clEnumValN(CodeModel::Tiny, "tiny", "Tiny code model"),
149                  clEnumValN(CodeModel::Small, "small", "Small code model"),
150                  clEnumValN(CodeModel::Kernel, "kernel", "Kernel code model"),
151                  clEnumValN(CodeModel::Medium, "medium", "Medium code model"),
152                  clEnumValN(CodeModel::Large, "large", "Large code model")));
153   CGBINDOPT(CodeModel);
154 
155   static cl::opt<ExceptionHandling> ExceptionModel(
156       "exception-model", cl::desc("exception model"),
157       cl::init(ExceptionHandling::None),
158       cl::values(
159           clEnumValN(ExceptionHandling::None, "default",
160                      "default exception handling model"),
161           clEnumValN(ExceptionHandling::DwarfCFI, "dwarf",
162                      "DWARF-like CFI based exception handling"),
163           clEnumValN(ExceptionHandling::SjLj, "sjlj",
164                      "SjLj exception handling"),
165           clEnumValN(ExceptionHandling::ARM, "arm", "ARM EHABI exceptions"),
166           clEnumValN(ExceptionHandling::WinEH, "wineh",
167                      "Windows exception model"),
168           clEnumValN(ExceptionHandling::Wasm, "wasm",
169                      "WebAssembly exception handling")));
170   CGBINDOPT(ExceptionModel);
171 
172   static cl::opt<CodeGenFileType> FileType(
173       "filetype", cl::init(CGFT_AssemblyFile),
174       cl::desc(
175           "Choose a file type (not all types are supported by all targets):"),
176       cl::values(
177           clEnumValN(CGFT_AssemblyFile, "asm", "Emit an assembly ('.s') file"),
178           clEnumValN(CGFT_ObjectFile, "obj",
179                      "Emit a native object ('.o') file"),
180           clEnumValN(CGFT_Null, "null",
181                      "Emit nothing, for performance testing")));
182   CGBINDOPT(FileType);
183 
184   static cl::opt<FramePointerKind> FramePointerUsage(
185       "frame-pointer",
186       cl::desc("Specify frame pointer elimination optimization"),
187       cl::init(FramePointerKind::None),
188       cl::values(
189           clEnumValN(FramePointerKind::All, "all",
190                      "Disable frame pointer elimination"),
191           clEnumValN(FramePointerKind::NonLeaf, "non-leaf",
192                      "Disable frame pointer elimination for non-leaf frame"),
193           clEnumValN(FramePointerKind::None, "none",
194                      "Enable frame pointer elimination")));
195   CGBINDOPT(FramePointerUsage);
196 
197   static cl::opt<bool> EnableUnsafeFPMath(
198       "enable-unsafe-fp-math",
199       cl::desc("Enable optimizations that may decrease FP precision"),
200       cl::init(false));
201   CGBINDOPT(EnableUnsafeFPMath);
202 
203   static cl::opt<bool> EnableNoInfsFPMath(
204       "enable-no-infs-fp-math",
205       cl::desc("Enable FP math optimizations that assume no +-Infs"),
206       cl::init(false));
207   CGBINDOPT(EnableNoInfsFPMath);
208 
209   static cl::opt<bool> EnableNoNaNsFPMath(
210       "enable-no-nans-fp-math",
211       cl::desc("Enable FP math optimizations that assume no NaNs"),
212       cl::init(false));
213   CGBINDOPT(EnableNoNaNsFPMath);
214 
215   static cl::opt<bool> EnableNoSignedZerosFPMath(
216       "enable-no-signed-zeros-fp-math",
217       cl::desc("Enable FP math optimizations that assume "
218                "the sign of 0 is insignificant"),
219       cl::init(false));
220   CGBINDOPT(EnableNoSignedZerosFPMath);
221 
222   static cl::opt<bool> EnableNoTrappingFPMath(
223       "enable-no-trapping-fp-math",
224       cl::desc("Enable setting the FP exceptions build "
225                "attribute not to use exceptions"),
226       cl::init(false));
227   CGBINDOPT(EnableNoTrappingFPMath);
228 
229   static const auto DenormFlagEnumOptions =
230   cl::values(clEnumValN(DenormalMode::IEEE, "ieee",
231                         "IEEE 754 denormal numbers"),
232              clEnumValN(DenormalMode::PreserveSign, "preserve-sign",
233                         "the sign of a  flushed-to-zero number is preserved "
234                         "in the sign of 0"),
235              clEnumValN(DenormalMode::PositiveZero, "positive-zero",
236                         "denormals are flushed to positive zero"));
237 
238   // FIXME: Doesn't have way to specify separate input and output modes.
239   static cl::opt<DenormalMode::DenormalModeKind> DenormalFPMath(
240     "denormal-fp-math",
241     cl::desc("Select which denormal numbers the code is permitted to require"),
242     cl::init(DenormalMode::IEEE),
243     DenormFlagEnumOptions);
244   CGBINDOPT(DenormalFPMath);
245 
246   static cl::opt<DenormalMode::DenormalModeKind> DenormalFP32Math(
247     "denormal-fp-math-f32",
248     cl::desc("Select which denormal numbers the code is permitted to require for float"),
249     cl::init(DenormalMode::Invalid),
250     DenormFlagEnumOptions);
251   CGBINDOPT(DenormalFP32Math);
252 
253   static cl::opt<bool> EnableHonorSignDependentRoundingFPMath(
254       "enable-sign-dependent-rounding-fp-math", cl::Hidden,
255       cl::desc("Force codegen to assume rounding mode can change dynamically"),
256       cl::init(false));
257   CGBINDOPT(EnableHonorSignDependentRoundingFPMath);
258 
259   static cl::opt<FloatABI::ABIType> FloatABIForCalls(
260       "float-abi", cl::desc("Choose float ABI type"),
261       cl::init(FloatABI::Default),
262       cl::values(clEnumValN(FloatABI::Default, "default",
263                             "Target default float ABI type"),
264                  clEnumValN(FloatABI::Soft, "soft",
265                             "Soft float ABI (implied by -soft-float)"),
266                  clEnumValN(FloatABI::Hard, "hard",
267                             "Hard float ABI (uses FP registers)")));
268   CGBINDOPT(FloatABIForCalls);
269 
270   static cl::opt<FPOpFusion::FPOpFusionMode> FuseFPOps(
271       "fp-contract", cl::desc("Enable aggressive formation of fused FP ops"),
272       cl::init(FPOpFusion::Standard),
273       cl::values(
274           clEnumValN(FPOpFusion::Fast, "fast",
275                      "Fuse FP ops whenever profitable"),
276           clEnumValN(FPOpFusion::Standard, "on", "Only fuse 'blessed' FP ops."),
277           clEnumValN(FPOpFusion::Strict, "off",
278                      "Only fuse FP ops when the result won't be affected.")));
279   CGBINDOPT(FuseFPOps);
280 
281   static cl::opt<bool> DontPlaceZerosInBSS(
282       "nozero-initialized-in-bss",
283       cl::desc("Don't place zero-initialized symbols into bss section"),
284       cl::init(false));
285   CGBINDOPT(DontPlaceZerosInBSS);
286 
287   static cl::opt<bool> EnableAIXExtendedAltivecABI(
288       "vec-extabi", cl::desc("Enable the AIX Extended Altivec ABI."),
289       cl::init(false));
290   CGBINDOPT(EnableAIXExtendedAltivecABI);
291 
292   static cl::opt<bool> EnableGuaranteedTailCallOpt(
293       "tailcallopt",
294       cl::desc(
295           "Turn fastcc calls into tail calls by (potentially) changing ABI."),
296       cl::init(false));
297   CGBINDOPT(EnableGuaranteedTailCallOpt);
298 
299   static cl::opt<bool> DisableTailCalls(
300       "disable-tail-calls", cl::desc("Never emit tail calls"), cl::init(false));
301   CGBINDOPT(DisableTailCalls);
302 
303   static cl::opt<bool> StackSymbolOrdering(
304       "stack-symbol-ordering", cl::desc("Order local stack symbols."),
305       cl::init(true));
306   CGBINDOPT(StackSymbolOrdering);
307 
308   static cl::opt<bool> StackRealign(
309       "stackrealign",
310       cl::desc("Force align the stack to the minimum alignment"),
311       cl::init(false));
312   CGBINDOPT(StackRealign);
313 
314   static cl::opt<std::string> TrapFuncName(
315       "trap-func", cl::Hidden,
316       cl::desc("Emit a call to trap function rather than a trap instruction"),
317       cl::init(""));
318   CGBINDOPT(TrapFuncName);
319 
320   static cl::opt<bool> UseCtors("use-ctors",
321                                 cl::desc("Use .ctors instead of .init_array."),
322                                 cl::init(false));
323   CGBINDOPT(UseCtors);
324 
325   static cl::opt<bool> RelaxELFRelocations(
326       "relax-elf-relocations",
327       cl::desc(
328           "Emit GOTPCRELX/REX_GOTPCRELX instead of GOTPCREL on x86-64 ELF"),
329       cl::init(false));
330   CGBINDOPT(RelaxELFRelocations);
331 
332   static cl::opt<bool> DataSections(
333       "data-sections", cl::desc("Emit data into separate sections"),
334       cl::init(false));
335   CGBINDOPT(DataSections);
336 
337   static cl::opt<bool> FunctionSections(
338       "function-sections", cl::desc("Emit functions into separate sections"),
339       cl::init(false));
340   CGBINDOPT(FunctionSections);
341 
342   static cl::opt<bool> IgnoreXCOFFVisibility(
343       "ignore-xcoff-visibility",
344       cl::desc("Not emit the visibility attribute for asm in AIX OS or give "
345                "all symbols 'unspecified' visibility in XCOFF object file"),
346       cl::init(false));
347   CGBINDOPT(IgnoreXCOFFVisibility);
348 
349   static cl::opt<bool> XCOFFTracebackTable(
350       "xcoff-traceback-table", cl::desc("Emit the XCOFF traceback table"),
351       cl::init(true));
352   CGBINDOPT(XCOFFTracebackTable);
353 
354   static cl::opt<std::string> BBSections(
355       "basic-block-sections",
356       cl::desc("Emit basic blocks into separate sections"),
357       cl::value_desc("all | <function list (file)> | labels | none"),
358       cl::init("none"));
359   CGBINDOPT(BBSections);
360 
361   static cl::opt<unsigned> TLSSize(
362       "tls-size", cl::desc("Bit size of immediate TLS offsets"), cl::init(0));
363   CGBINDOPT(TLSSize);
364 
365   static cl::opt<bool> EmulatedTLS(
366       "emulated-tls", cl::desc("Use emulated TLS model"), cl::init(false));
367   CGBINDOPT(EmulatedTLS);
368 
369   static cl::opt<bool> UniqueSectionNames(
370       "unique-section-names", cl::desc("Give unique names to every section"),
371       cl::init(true));
372   CGBINDOPT(UniqueSectionNames);
373 
374   static cl::opt<bool> UniqueBasicBlockSectionNames(
375       "unique-basic-block-section-names",
376       cl::desc("Give unique names to every basic block section"),
377       cl::init(false));
378   CGBINDOPT(UniqueBasicBlockSectionNames);
379 
380   static cl::opt<EABI> EABIVersion(
381       "meabi", cl::desc("Set EABI type (default depends on triple):"),
382       cl::init(EABI::Default),
383       cl::values(
384           clEnumValN(EABI::Default, "default", "Triple default EABI version"),
385           clEnumValN(EABI::EABI4, "4", "EABI version 4"),
386           clEnumValN(EABI::EABI5, "5", "EABI version 5"),
387           clEnumValN(EABI::GNU, "gnu", "EABI GNU")));
388   CGBINDOPT(EABIVersion);
389 
390   static cl::opt<DebuggerKind> DebuggerTuningOpt(
391       "debugger-tune", cl::desc("Tune debug info for a particular debugger"),
392       cl::init(DebuggerKind::Default),
393       cl::values(
394           clEnumValN(DebuggerKind::GDB, "gdb", "gdb"),
395           clEnumValN(DebuggerKind::LLDB, "lldb", "lldb"),
396           clEnumValN(DebuggerKind::DBX, "dbx", "dbx"),
397           clEnumValN(DebuggerKind::SCE, "sce", "SCE targets (e.g. PS4)")));
398   CGBINDOPT(DebuggerTuningOpt);
399 
400   static cl::opt<bool> EnableStackSizeSection(
401       "stack-size-section",
402       cl::desc("Emit a section containing stack size metadata"),
403       cl::init(false));
404   CGBINDOPT(EnableStackSizeSection);
405 
406   static cl::opt<bool> EnableAddrsig(
407       "addrsig", cl::desc("Emit an address-significance table"),
408       cl::init(false));
409   CGBINDOPT(EnableAddrsig);
410 
411   static cl::opt<bool> EmitCallSiteInfo(
412       "emit-call-site-info",
413       cl::desc(
414           "Emit call site debug information, if debug information is enabled."),
415       cl::init(false));
416   CGBINDOPT(EmitCallSiteInfo);
417 
418   static cl::opt<bool> EnableDebugEntryValues(
419       "debug-entry-values",
420       cl::desc("Enable debug info for the debug entry values."),
421       cl::init(false));
422   CGBINDOPT(EnableDebugEntryValues);
423 
424   static cl::opt<bool> PseudoProbeForProfiling(
425       "pseudo-probe-for-profiling", cl::desc("Emit pseudo probes for AutoFDO"),
426       cl::init(false));
427   CGBINDOPT(PseudoProbeForProfiling);
428 
429   static cl::opt<bool> ValueTrackingVariableLocations(
430       "experimental-debug-variable-locations",
431       cl::desc("Use experimental new value-tracking variable locations"),
432       cl::init(false));
433   CGBINDOPT(ValueTrackingVariableLocations);
434 
435   static cl::opt<bool> EnableMachineFunctionSplitter(
436       "split-machine-functions",
437       cl::desc("Split out cold basic blocks from machine functions based on "
438                "profile information"),
439       cl::init(false));
440   CGBINDOPT(EnableMachineFunctionSplitter);
441 
442   static cl::opt<bool> ForceDwarfFrameSection(
443       "force-dwarf-frame-section",
444       cl::desc("Always emit a debug frame section."), cl::init(false));
445   CGBINDOPT(ForceDwarfFrameSection);
446 
447   static cl::opt<bool> XRayOmitFunctionIndex(
448       "no-xray-index", cl::desc("Don't emit xray_fn_idx section"),
449       cl::init(false));
450   CGBINDOPT(XRayOmitFunctionIndex);
451 
452   static cl::opt<bool> DebugStrictDwarf(
453       "strict-dwarf", cl::desc("use strict dwarf"), cl::init(false));
454   CGBINDOPT(DebugStrictDwarf);
455 
456   static cl::opt<unsigned> AlignLoops("align-loops",
457                                       cl::desc("Default alignment for loops"));
458   CGBINDOPT(AlignLoops);
459 
460 #undef CGBINDOPT
461 
462   mc::RegisterMCTargetOptionsFlags();
463 }
464 
465 llvm::BasicBlockSection
466 codegen::getBBSectionsMode(llvm::TargetOptions &Options) {
467   if (getBBSections() == "all")
468     return BasicBlockSection::All;
469   else if (getBBSections() == "labels")
470     return BasicBlockSection::Labels;
471   else if (getBBSections() == "none")
472     return BasicBlockSection::None;
473   else {
474     ErrorOr<std::unique_ptr<MemoryBuffer>> MBOrErr =
475         MemoryBuffer::getFile(getBBSections());
476     if (!MBOrErr) {
477       errs() << "Error loading basic block sections function list file: "
478              << MBOrErr.getError().message() << "\n";
479     } else {
480       Options.BBSectionsFuncListBuf = std::move(*MBOrErr);
481     }
482     return BasicBlockSection::List;
483   }
484 }
485 
486 // Common utility function tightly tied to the options listed here. Initializes
487 // a TargetOptions object with CodeGen flags and returns it.
488 TargetOptions
489 codegen::InitTargetOptionsFromCodeGenFlags(const Triple &TheTriple) {
490   TargetOptions Options;
491   Options.AllowFPOpFusion = getFuseFPOps();
492   Options.UnsafeFPMath = getEnableUnsafeFPMath();
493   Options.NoInfsFPMath = getEnableNoInfsFPMath();
494   Options.NoNaNsFPMath = getEnableNoNaNsFPMath();
495   Options.NoSignedZerosFPMath = getEnableNoSignedZerosFPMath();
496   Options.NoTrappingFPMath = getEnableNoTrappingFPMath();
497 
498   DenormalMode::DenormalModeKind DenormKind = getDenormalFPMath();
499 
500   // FIXME: Should have separate input and output flags
501   Options.setFPDenormalMode(DenormalMode(DenormKind, DenormKind));
502 
503   Options.HonorSignDependentRoundingFPMathOption =
504       getEnableHonorSignDependentRoundingFPMath();
505   if (getFloatABIForCalls() != FloatABI::Default)
506     Options.FloatABIType = getFloatABIForCalls();
507   Options.EnableAIXExtendedAltivecABI = getEnableAIXExtendedAltivecABI();
508   Options.NoZerosInBSS = getDontPlaceZerosInBSS();
509   Options.GuaranteedTailCallOpt = getEnableGuaranteedTailCallOpt();
510   Options.StackSymbolOrdering = getStackSymbolOrdering();
511   Options.UseInitArray = !getUseCtors();
512   Options.RelaxELFRelocations = getRelaxELFRelocations();
513   Options.DataSections =
514       getExplicitDataSections().getValueOr(TheTriple.hasDefaultDataSections());
515   Options.FunctionSections = getFunctionSections();
516   Options.IgnoreXCOFFVisibility = getIgnoreXCOFFVisibility();
517   Options.XCOFFTracebackTable = getXCOFFTracebackTable();
518   Options.BBSections = getBBSectionsMode(Options);
519   Options.UniqueSectionNames = getUniqueSectionNames();
520   Options.UniqueBasicBlockSectionNames = getUniqueBasicBlockSectionNames();
521   Options.TLSSize = getTLSSize();
522   Options.EmulatedTLS = getEmulatedTLS();
523   Options.ExplicitEmulatedTLS = EmulatedTLSView->getNumOccurrences() > 0;
524   Options.ExceptionModel = getExceptionModel();
525   Options.EmitStackSizeSection = getEnableStackSizeSection();
526   Options.EnableMachineFunctionSplitter = getEnableMachineFunctionSplitter();
527   Options.EmitAddrsig = getEnableAddrsig();
528   Options.EmitCallSiteInfo = getEmitCallSiteInfo();
529   Options.EnableDebugEntryValues = getEnableDebugEntryValues();
530   Options.PseudoProbeForProfiling = getPseudoProbeForProfiling();
531   Options.ValueTrackingVariableLocations = getValueTrackingVariableLocations();
532   Options.ForceDwarfFrameSection = getForceDwarfFrameSection();
533   Options.XRayOmitFunctionIndex = getXRayOmitFunctionIndex();
534   Options.DebugStrictDwarf = getDebugStrictDwarf();
535   Options.LoopAlignment = getAlignLoops();
536 
537   Options.MCOptions = mc::InitMCTargetOptionsFromFlags();
538 
539   Options.ThreadModel = getThreadModel();
540   Options.EABIVersion = getEABIVersion();
541   Options.DebuggerTuning = getDebuggerTuningOpt();
542 
543   return Options;
544 }
545 
546 std::string codegen::getCPUStr() {
547   // If user asked for the 'native' CPU, autodetect here. If autodection fails,
548   // this will set the CPU to an empty string which tells the target to
549   // pick a basic default.
550   if (getMCPU() == "native")
551     return std::string(sys::getHostCPUName());
552 
553   return getMCPU();
554 }
555 
556 std::string codegen::getFeaturesStr() {
557   SubtargetFeatures Features;
558 
559   // If user asked for the 'native' CPU, we need to autodetect features.
560   // This is necessary for x86 where the CPU might not support all the
561   // features the autodetected CPU name lists in the target. For example,
562   // not all Sandybridge processors support AVX.
563   if (getMCPU() == "native") {
564     StringMap<bool> HostFeatures;
565     if (sys::getHostCPUFeatures(HostFeatures))
566       for (auto &F : HostFeatures)
567         Features.AddFeature(F.first(), F.second);
568   }
569 
570   for (auto const &MAttr : getMAttrs())
571     Features.AddFeature(MAttr);
572 
573   return Features.getString();
574 }
575 
576 std::vector<std::string> codegen::getFeatureList() {
577   SubtargetFeatures Features;
578 
579   // If user asked for the 'native' CPU, we need to autodetect features.
580   // This is necessary for x86 where the CPU might not support all the
581   // features the autodetected CPU name lists in the target. For example,
582   // not all Sandybridge processors support AVX.
583   if (getMCPU() == "native") {
584     StringMap<bool> HostFeatures;
585     if (sys::getHostCPUFeatures(HostFeatures))
586       for (auto &F : HostFeatures)
587         Features.AddFeature(F.first(), F.second);
588   }
589 
590   for (auto const &MAttr : getMAttrs())
591     Features.AddFeature(MAttr);
592 
593   return Features.getFeatures();
594 }
595 
596 void codegen::renderBoolStringAttr(AttrBuilder &B, StringRef Name, bool Val) {
597   B.addAttribute(Name, Val ? "true" : "false");
598 }
599 
600 #define HANDLE_BOOL_ATTR(CL, AttrName)                                         \
601   do {                                                                         \
602     if (CL->getNumOccurrences() > 0 && !F.hasFnAttribute(AttrName))            \
603       renderBoolStringAttr(NewAttrs, AttrName, *CL);                           \
604   } while (0)
605 
606 /// Set function attributes of function \p F based on CPU, Features, and command
607 /// line flags.
608 void codegen::setFunctionAttributes(StringRef CPU, StringRef Features,
609                                     Function &F) {
610   auto &Ctx = F.getContext();
611   AttributeList Attrs = F.getAttributes();
612   AttrBuilder NewAttrs;
613 
614   if (!CPU.empty() && !F.hasFnAttribute("target-cpu"))
615     NewAttrs.addAttribute("target-cpu", CPU);
616   if (!Features.empty()) {
617     // Append the command line features to any that are already on the function.
618     StringRef OldFeatures =
619         F.getFnAttribute("target-features").getValueAsString();
620     if (OldFeatures.empty())
621       NewAttrs.addAttribute("target-features", Features);
622     else {
623       SmallString<256> Appended(OldFeatures);
624       Appended.push_back(',');
625       Appended.append(Features);
626       NewAttrs.addAttribute("target-features", Appended);
627     }
628   }
629   if (FramePointerUsageView->getNumOccurrences() > 0 &&
630       !F.hasFnAttribute("frame-pointer")) {
631     if (getFramePointerUsage() == FramePointerKind::All)
632       NewAttrs.addAttribute("frame-pointer", "all");
633     else if (getFramePointerUsage() == FramePointerKind::NonLeaf)
634       NewAttrs.addAttribute("frame-pointer", "non-leaf");
635     else if (getFramePointerUsage() == FramePointerKind::None)
636       NewAttrs.addAttribute("frame-pointer", "none");
637   }
638   if (DisableTailCallsView->getNumOccurrences() > 0)
639     NewAttrs.addAttribute("disable-tail-calls",
640                           toStringRef(getDisableTailCalls()));
641   if (getStackRealign())
642     NewAttrs.addAttribute("stackrealign");
643 
644   HANDLE_BOOL_ATTR(EnableUnsafeFPMathView, "unsafe-fp-math");
645   HANDLE_BOOL_ATTR(EnableNoInfsFPMathView, "no-infs-fp-math");
646   HANDLE_BOOL_ATTR(EnableNoNaNsFPMathView, "no-nans-fp-math");
647   HANDLE_BOOL_ATTR(EnableNoSignedZerosFPMathView, "no-signed-zeros-fp-math");
648 
649   if (DenormalFPMathView->getNumOccurrences() > 0 &&
650       !F.hasFnAttribute("denormal-fp-math")) {
651     DenormalMode::DenormalModeKind DenormKind = getDenormalFPMath();
652 
653     // FIXME: Command line flag should expose separate input/output modes.
654     NewAttrs.addAttribute("denormal-fp-math",
655                           DenormalMode(DenormKind, DenormKind).str());
656   }
657 
658   if (DenormalFP32MathView->getNumOccurrences() > 0 &&
659       !F.hasFnAttribute("denormal-fp-math-f32")) {
660     // FIXME: Command line flag should expose separate input/output modes.
661     DenormalMode::DenormalModeKind DenormKind = getDenormalFP32Math();
662 
663     NewAttrs.addAttribute(
664       "denormal-fp-math-f32",
665       DenormalMode(DenormKind, DenormKind).str());
666   }
667 
668   if (TrapFuncNameView->getNumOccurrences() > 0)
669     for (auto &B : F)
670       for (auto &I : B)
671         if (auto *Call = dyn_cast<CallInst>(&I))
672           if (const auto *F = Call->getCalledFunction())
673             if (F->getIntrinsicID() == Intrinsic::debugtrap ||
674                 F->getIntrinsicID() == Intrinsic::trap)
675               Call->addAttribute(
676                   AttributeList::FunctionIndex,
677                   Attribute::get(Ctx, "trap-func-name", getTrapFuncName()));
678 
679   // Let NewAttrs override Attrs.
680   F.setAttributes(
681       Attrs.addAttributes(Ctx, AttributeList::FunctionIndex, NewAttrs));
682 }
683 
684 /// Set function attributes of functions in Module M based on CPU,
685 /// Features, and command line flags.
686 void codegen::setFunctionAttributes(StringRef CPU, StringRef Features,
687                                     Module &M) {
688   for (Function &F : M)
689     setFunctionAttributes(CPU, Features, F);
690 }
691