1 //===-- CommandFlags.h - Command Line Flags Interface -----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains codegen-specific flags that are shared between different
11 // command line tools. The tools "llc" and "opt" both use this file to prevent
14 //===----------------------------------------------------------------------===//
16 #include "llvm/ADT/StringExtras.h"
17 #include "llvm/IR/Instructions.h"
18 #include "llvm/IR/Intrinsics.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/MC/MCTargetOptionsCommandFlags.inc"
21 #include "llvm/MC/SubtargetFeature.h"
22 #include "llvm/Support/CodeGen.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/Host.h"
25 #include "llvm/Target/TargetMachine.h"
26 #include "llvm/Target/TargetOptions.h"
30 static cl::opt<std::string>
32 cl::desc("Architecture to generate code for (see --version)"));
34 static cl::opt<std::string>
36 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
37 cl::value_desc("cpu-name"), cl::init(""));
39 static cl::list<std::string>
40 MAttrs("mattr", cl::CommaSeparated,
41 cl::desc("Target specific attributes (-mattr=help for details)"),
42 cl::value_desc("a1,+a2,-a3,..."));
44 static cl::opt<Reloc::Model> RelocModel(
45 "relocation-model", cl::desc("Choose relocation model"),
47 clEnumValN(Reloc::Static, "static", "Non-relocatable code"),
48 clEnumValN(Reloc::PIC_, "pic",
49 "Fully relocatable, position independent code"),
50 clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
51 "Relocatable external references, non-relocatable code"),
52 clEnumValN(Reloc::ROPI, "ropi",
53 "Code and read-only data relocatable, accessed PC-relative"),
56 "Read-write data relocatable, accessed relative to static base"),
57 clEnumValN(Reloc::ROPI_RWPI, "ropi-rwpi",
58 "Combination of ropi and rwpi")));
60 LLVM_ATTRIBUTE_UNUSED static Optional<Reloc::Model> getRelocModel() {
61 if (RelocModel.getNumOccurrences()) {
62 Reloc::Model R = RelocModel;
68 static cl::opt<ThreadModel::Model> TMModel(
69 "thread-model", cl::desc("Choose threading model"),
70 cl::init(ThreadModel::POSIX),
71 cl::values(clEnumValN(ThreadModel::POSIX, "posix", "POSIX thread model"),
72 clEnumValN(ThreadModel::Single, "single",
73 "Single thread model")));
75 static cl::opt<llvm::CodeModel::Model> CMModel(
76 "code-model", cl::desc("Choose code model"),
77 cl::values(clEnumValN(CodeModel::Small, "small", "Small code model"),
78 clEnumValN(CodeModel::Kernel, "kernel", "Kernel code model"),
79 clEnumValN(CodeModel::Medium, "medium", "Medium code model"),
80 clEnumValN(CodeModel::Large, "large", "Large code model")));
82 LLVM_ATTRIBUTE_UNUSED static Optional<CodeModel::Model> getCodeModel() {
83 if (CMModel.getNumOccurrences()) {
84 CodeModel::Model M = CMModel;
90 static cl::opt<llvm::ExceptionHandling> ExceptionModel(
91 "exception-model", cl::desc("exception model"),
92 cl::init(ExceptionHandling::None),
94 clEnumValN(ExceptionHandling::None, "default",
95 "default exception handling model"),
96 clEnumValN(ExceptionHandling::DwarfCFI, "dwarf",
97 "DWARF-like CFI based exception handling"),
98 clEnumValN(ExceptionHandling::SjLj, "sjlj", "SjLj exception handling"),
99 clEnumValN(ExceptionHandling::ARM, "arm", "ARM EHABI exceptions"),
100 clEnumValN(ExceptionHandling::WinEH, "wineh",
101 "Windows exception model"),
102 clEnumValN(ExceptionHandling::Wasm, "wasm",
103 "WebAssembly exception handling")));
105 static cl::opt<TargetMachine::CodeGenFileType> FileType(
106 "filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
108 "Choose a file type (not all types are supported by all targets):"),
109 cl::values(clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
110 "Emit an assembly ('.s') file"),
111 clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
112 "Emit a native object ('.o') file"),
113 clEnumValN(TargetMachine::CGFT_Null, "null",
114 "Emit nothing, for performance testing")));
117 DisableFPElim("disable-fp-elim",
118 cl::desc("Disable frame pointer elimination optimization"),
121 static cl::opt<bool> EnableUnsafeFPMath(
122 "enable-unsafe-fp-math",
123 cl::desc("Enable optimizations that may decrease FP precision"),
126 static cl::opt<bool> EnableNoInfsFPMath(
127 "enable-no-infs-fp-math",
128 cl::desc("Enable FP math optimizations that assume no +-Infs"),
131 static cl::opt<bool> EnableNoNaNsFPMath(
132 "enable-no-nans-fp-math",
133 cl::desc("Enable FP math optimizations that assume no NaNs"),
136 static cl::opt<bool> EnableNoSignedZerosFPMath(
137 "enable-no-signed-zeros-fp-math",
138 cl::desc("Enable FP math optimizations that assume "
139 "the sign of 0 is insignificant"),
143 EnableNoTrappingFPMath("enable-no-trapping-fp-math",
144 cl::desc("Enable setting the FP exceptions build "
145 "attribute not to use exceptions"),
148 static cl::opt<llvm::FPDenormal::DenormalMode> DenormalMode(
150 cl::desc("Select which denormal numbers the code is permitted to require"),
151 cl::init(FPDenormal::IEEE),
152 cl::values(clEnumValN(FPDenormal::IEEE, "ieee",
153 "IEEE 754 denormal numbers"),
154 clEnumValN(FPDenormal::PreserveSign, "preserve-sign",
155 "the sign of a flushed-to-zero number is preserved "
157 clEnumValN(FPDenormal::PositiveZero, "positive-zero",
158 "denormals are flushed to positive zero")));
160 static cl::opt<bool> EnableHonorSignDependentRoundingFPMath(
161 "enable-sign-dependent-rounding-fp-math", cl::Hidden,
162 cl::desc("Force codegen to assume rounding mode can change dynamically"),
165 static cl::opt<llvm::FloatABI::ABIType> FloatABIForCalls(
166 "float-abi", cl::desc("Choose float ABI type"), cl::init(FloatABI::Default),
167 cl::values(clEnumValN(FloatABI::Default, "default",
168 "Target default float ABI type"),
169 clEnumValN(FloatABI::Soft, "soft",
170 "Soft float ABI (implied by -soft-float)"),
171 clEnumValN(FloatABI::Hard, "hard",
172 "Hard float ABI (uses FP registers)")));
174 static cl::opt<llvm::FPOpFusion::FPOpFusionMode> FuseFPOps(
175 "fp-contract", cl::desc("Enable aggressive formation of fused FP ops"),
176 cl::init(FPOpFusion::Standard),
178 clEnumValN(FPOpFusion::Fast, "fast", "Fuse FP ops whenever profitable"),
179 clEnumValN(FPOpFusion::Standard, "on", "Only fuse 'blessed' FP ops."),
180 clEnumValN(FPOpFusion::Strict, "off",
181 "Only fuse FP ops when the result won't be affected.")));
183 static cl::opt<bool> DontPlaceZerosInBSS(
184 "nozero-initialized-in-bss",
185 cl::desc("Don't place zero-initialized symbols into bss section"),
188 static cl::opt<bool> EnableGuaranteedTailCallOpt(
191 "Turn fastcc calls into tail calls by (potentially) changing ABI."),
194 static cl::opt<bool> DisableTailCalls("disable-tail-calls",
195 cl::desc("Never emit tail calls"),
198 static cl::opt<bool> StackSymbolOrdering("stack-symbol-ordering",
199 cl::desc("Order local stack symbols."),
202 static cl::opt<unsigned>
203 OverrideStackAlignment("stack-alignment",
204 cl::desc("Override default stack alignment"),
208 StackRealign("stackrealign",
209 cl::desc("Force align the stack to the minimum alignment"),
212 static cl::opt<std::string> TrapFuncName(
213 "trap-func", cl::Hidden,
214 cl::desc("Emit a call to trap function rather than a trap instruction"),
217 static cl::opt<bool> UseCtors("use-ctors",
218 cl::desc("Use .ctors instead of .init_array."),
221 static cl::opt<bool> RelaxELFRelocations(
222 "relax-elf-relocations",
223 cl::desc("Emit GOTPCRELX/REX_GOTPCRELX instead of GOTPCREL on x86-64 ELF"),
226 static cl::opt<bool> DataSections("data-sections",
227 cl::desc("Emit data into separate sections"),
231 FunctionSections("function-sections",
232 cl::desc("Emit functions into separate sections"),
235 static cl::opt<bool> EmulatedTLS("emulated-tls",
236 cl::desc("Use emulated TLS model"),
240 UniqueSectionNames("unique-section-names",
241 cl::desc("Give unique names to every section"),
244 static cl::opt<llvm::EABI>
245 EABIVersion("meabi", cl::desc("Set EABI type (default depends on triple):"),
246 cl::init(EABI::Default),
247 cl::values(clEnumValN(EABI::Default, "default",
248 "Triple default EABI version"),
249 clEnumValN(EABI::EABI4, "4", "EABI version 4"),
250 clEnumValN(EABI::EABI5, "5", "EABI version 5"),
251 clEnumValN(EABI::GNU, "gnu", "EABI GNU")));
253 static cl::opt<DebuggerKind> DebuggerTuningOpt(
254 "debugger-tune", cl::desc("Tune debug info for a particular debugger"),
255 cl::init(DebuggerKind::Default),
256 cl::values(clEnumValN(DebuggerKind::GDB, "gdb", "gdb"),
257 clEnumValN(DebuggerKind::LLDB, "lldb", "lldb"),
258 clEnumValN(DebuggerKind::SCE, "sce", "SCE targets (e.g. PS4)")));
260 static cl::opt<bool> EnableStackSizeSection(
261 "stack-size-section",
262 cl::desc("Emit a section containing stack size metadata"), cl::init(false));
265 EnableAddrsig("addrsig", cl::desc("Emit an address-significance table"),
268 // Common utility function tightly tied to the options listed here. Initializes
269 // a TargetOptions object with CodeGen flags and returns it.
270 static TargetOptions InitTargetOptionsFromCodeGenFlags() {
271 TargetOptions Options;
272 Options.AllowFPOpFusion = FuseFPOps;
273 Options.UnsafeFPMath = EnableUnsafeFPMath;
274 Options.NoInfsFPMath = EnableNoInfsFPMath;
275 Options.NoNaNsFPMath = EnableNoNaNsFPMath;
276 Options.NoSignedZerosFPMath = EnableNoSignedZerosFPMath;
277 Options.NoTrappingFPMath = EnableNoTrappingFPMath;
278 Options.FPDenormalMode = DenormalMode;
279 Options.HonorSignDependentRoundingFPMathOption =
280 EnableHonorSignDependentRoundingFPMath;
281 if (FloatABIForCalls != FloatABI::Default)
282 Options.FloatABIType = FloatABIForCalls;
283 Options.NoZerosInBSS = DontPlaceZerosInBSS;
284 Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
285 Options.StackAlignmentOverride = OverrideStackAlignment;
286 Options.StackSymbolOrdering = StackSymbolOrdering;
287 Options.UseInitArray = !UseCtors;
288 Options.RelaxELFRelocations = RelaxELFRelocations;
289 Options.DataSections = DataSections;
290 Options.FunctionSections = FunctionSections;
291 Options.UniqueSectionNames = UniqueSectionNames;
292 Options.EmulatedTLS = EmulatedTLS;
293 Options.ExplicitEmulatedTLS = EmulatedTLS.getNumOccurrences() > 0;
294 Options.ExceptionModel = ExceptionModel;
295 Options.EmitStackSizeSection = EnableStackSizeSection;
296 Options.EmitAddrsig = EnableAddrsig;
298 Options.MCOptions = InitMCTargetOptionsFromFlags();
300 Options.ThreadModel = TMModel;
301 Options.EABIVersion = EABIVersion;
302 Options.DebuggerTuning = DebuggerTuningOpt;
307 LLVM_ATTRIBUTE_UNUSED static std::string getCPUStr() {
308 // If user asked for the 'native' CPU, autodetect here. If autodection fails,
309 // this will set the CPU to an empty string which tells the target to
310 // pick a basic default.
311 if (MCPU == "native")
312 return sys::getHostCPUName();
317 LLVM_ATTRIBUTE_UNUSED static std::string getFeaturesStr() {
318 SubtargetFeatures Features;
320 // If user asked for the 'native' CPU, we need to autodetect features.
321 // This is necessary for x86 where the CPU might not support all the
322 // features the autodetected CPU name lists in the target. For example,
323 // not all Sandybridge processors support AVX.
324 if (MCPU == "native") {
325 StringMap<bool> HostFeatures;
326 if (sys::getHostCPUFeatures(HostFeatures))
327 for (auto &F : HostFeatures)
328 Features.AddFeature(F.first(), F.second);
331 for (unsigned i = 0; i != MAttrs.size(); ++i)
332 Features.AddFeature(MAttrs[i]);
334 return Features.getString();
337 LLVM_ATTRIBUTE_UNUSED static std::vector<std::string> getFeatureList() {
338 SubtargetFeatures Features;
340 // If user asked for the 'native' CPU, we need to autodetect features.
341 // This is necessary for x86 where the CPU might not support all the
342 // features the autodetected CPU name lists in the target. For example,
343 // not all Sandybridge processors support AVX.
344 if (MCPU == "native") {
345 StringMap<bool> HostFeatures;
346 if (sys::getHostCPUFeatures(HostFeatures))
347 for (auto &F : HostFeatures)
348 Features.AddFeature(F.first(), F.second);
351 for (unsigned i = 0; i != MAttrs.size(); ++i)
352 Features.AddFeature(MAttrs[i]);
354 return Features.getFeatures();
357 /// Set function attributes of functions in Module M based on CPU,
358 /// Features, and command line flags.
359 LLVM_ATTRIBUTE_UNUSED static void
360 setFunctionAttributes(StringRef CPU, StringRef Features, Module &M) {
362 auto &Ctx = F.getContext();
363 AttributeList Attrs = F.getAttributes();
364 AttrBuilder NewAttrs;
367 NewAttrs.addAttribute("target-cpu", CPU);
368 if (!Features.empty())
369 NewAttrs.addAttribute("target-features", Features);
370 if (DisableFPElim.getNumOccurrences() > 0)
371 NewAttrs.addAttribute("no-frame-pointer-elim",
372 DisableFPElim ? "true" : "false");
373 if (DisableTailCalls.getNumOccurrences() > 0)
374 NewAttrs.addAttribute("disable-tail-calls",
375 toStringRef(DisableTailCalls));
377 NewAttrs.addAttribute("stackrealign");
379 if (TrapFuncName.getNumOccurrences() > 0)
382 if (auto *Call = dyn_cast<CallInst>(&I))
383 if (const auto *F = Call->getCalledFunction())
384 if (F->getIntrinsicID() == Intrinsic::debugtrap ||
385 F->getIntrinsicID() == Intrinsic::trap)
387 llvm::AttributeList::FunctionIndex,
388 Attribute::get(Ctx, "trap-func-name", TrapFuncName));
390 // Let NewAttrs override Attrs.
392 Attrs.addAttributes(Ctx, AttributeList::FunctionIndex, NewAttrs));