LLVM  9.0.0svn
CommandFlags.inc
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1 //===-- CommandFlags.h - 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/ADT/StringExtras.h"
16 #include "llvm/IR/Instructions.h"
17 #include "llvm/IR/Intrinsics.h"
18 #include "llvm/IR/Module.h"
21 #include "llvm/Support/CodeGen.h"
23 #include "llvm/Support/Host.h"
26 #include <string>
27 using namespace llvm;
28 
30  MArch("march",
31  cl::desc("Architecture to generate code for (see --version)"));
32 
34  MCPU("mcpu",
35  cl::desc("Target a specific cpu type (-mcpu=help for details)"),
36  cl::value_desc("cpu-name"), cl::init(""));
37 
39  MAttrs("mattr", cl::CommaSeparated,
40  cl::desc("Target specific attributes (-mattr=help for details)"),
41  cl::value_desc("a1,+a2,-a3,..."));
42 
43 static cl::opt<Reloc::Model> RelocModel(
44  "relocation-model", cl::desc("Choose relocation model"),
45  cl::values(
46  clEnumValN(Reloc::Static, "static", "Non-relocatable code"),
47  clEnumValN(Reloc::PIC_, "pic",
48  "Fully relocatable, position independent code"),
49  clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
50  "Relocatable external references, non-relocatable code"),
51  clEnumValN(Reloc::ROPI, "ropi",
52  "Code and read-only data relocatable, accessed PC-relative"),
53  clEnumValN(
54  Reloc::RWPI, "rwpi",
55  "Read-write data relocatable, accessed relative to static base"),
56  clEnumValN(Reloc::ROPI_RWPI, "ropi-rwpi",
57  "Combination of ropi and rwpi")));
58 
60  if (RelocModel.getNumOccurrences()) {
61  Reloc::Model R = RelocModel;
62  return R;
63  }
64  return None;
65 }
66 
67 static cl::opt<ThreadModel::Model> TMModel(
68  "thread-model", cl::desc("Choose threading model"),
70  cl::values(clEnumValN(ThreadModel::POSIX, "posix", "POSIX thread model"),
72  "Single thread model")));
73 
74 static cl::opt<llvm::CodeModel::Model> CMModel(
75  "code-model", cl::desc("Choose code model"),
76  cl::values(clEnumValN(CodeModel::Tiny, "tiny", "Tiny code model"),
77  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")));
81 
83  if (CMModel.getNumOccurrences()) {
84  CodeModel::Model M = CMModel;
85  return M;
86  }
87  return None;
88 }
89 
90 static cl::opt<llvm::ExceptionHandling> ExceptionModel(
91  "exception-model", cl::desc("exception model"),
93  cl::values(
95  "default exception handling model"),
97  "DWARF-like CFI based exception handling"),
98  clEnumValN(ExceptionHandling::SjLj, "sjlj", "SjLj exception handling"),
99  clEnumValN(ExceptionHandling::ARM, "arm", "ARM EHABI exceptions"),
101  "Windows exception model"),
103  "WebAssembly exception handling")));
104 
107  cl::desc(
108  "Choose a file type (not all types are supported by all targets):"),
110  "Emit an assembly ('.s') file"),
112  "Emit a native object ('.o') file"),
114  "Emit nothing, for performance testing")));
115 
116 static cl::opt<llvm::FramePointer::FP> FramePointerUsage(
117  "frame-pointer", cl::desc("Specify frame pointer elimination optimization"),
119  cl::values(
121  "Disable frame pointer elimination"),
123  "Disable frame pointer elimination for non-leaf frame"),
125  "Enable frame pointer elimination")));
126 
127 static cl::opt<bool> EnableUnsafeFPMath(
128  "enable-unsafe-fp-math",
129  cl::desc("Enable optimizations that may decrease FP precision"),
130  cl::init(false));
131 
132 static cl::opt<bool> EnableNoInfsFPMath(
133  "enable-no-infs-fp-math",
134  cl::desc("Enable FP math optimizations that assume no +-Infs"),
135  cl::init(false));
136 
137 static cl::opt<bool> EnableNoNaNsFPMath(
138  "enable-no-nans-fp-math",
139  cl::desc("Enable FP math optimizations that assume no NaNs"),
140  cl::init(false));
141 
142 static cl::opt<bool> EnableNoSignedZerosFPMath(
143  "enable-no-signed-zeros-fp-math",
144  cl::desc("Enable FP math optimizations that assume "
145  "the sign of 0 is insignificant"),
146  cl::init(false));
147 
148 static cl::opt<bool>
149  EnableNoTrappingFPMath("enable-no-trapping-fp-math",
150  cl::desc("Enable setting the FP exceptions build "
151  "attribute not to use exceptions"),
152  cl::init(false));
153 
155  "denormal-fp-math",
156  cl::desc("Select which denormal numbers the code is permitted to require"),
159  "IEEE 754 denormal numbers"),
160  clEnumValN(FPDenormal::PreserveSign, "preserve-sign",
161  "the sign of a flushed-to-zero number is preserved "
162  "in the sign of 0"),
163  clEnumValN(FPDenormal::PositiveZero, "positive-zero",
164  "denormals are flushed to positive zero")));
165 
166 static cl::opt<bool> EnableHonorSignDependentRoundingFPMath(
167  "enable-sign-dependent-rounding-fp-math", cl::Hidden,
168  cl::desc("Force codegen to assume rounding mode can change dynamically"),
169  cl::init(false));
170 
171 static cl::opt<llvm::FloatABI::ABIType> FloatABIForCalls(
172  "float-abi", cl::desc("Choose float ABI type"), cl::init(FloatABI::Default),
174  "Target default float ABI type"),
175  clEnumValN(FloatABI::Soft, "soft",
176  "Soft float ABI (implied by -soft-float)"),
177  clEnumValN(FloatABI::Hard, "hard",
178  "Hard float ABI (uses FP registers)")));
179 
181  "fp-contract", cl::desc("Enable aggressive formation of fused FP ops"),
183  cl::values(
184  clEnumValN(FPOpFusion::Fast, "fast", "Fuse FP ops whenever profitable"),
185  clEnumValN(FPOpFusion::Standard, "on", "Only fuse 'blessed' FP ops."),
187  "Only fuse FP ops when the result won't be affected.")));
188 
189 static cl::opt<bool> DontPlaceZerosInBSS(
190  "nozero-initialized-in-bss",
191  cl::desc("Don't place zero-initialized symbols into bss section"),
192  cl::init(false));
193 
194 static cl::opt<bool> EnableGuaranteedTailCallOpt(
195  "tailcallopt",
196  cl::desc(
197  "Turn fastcc calls into tail calls by (potentially) changing ABI."),
198  cl::init(false));
199 
200 static cl::opt<bool> DisableTailCalls("disable-tail-calls",
201  cl::desc("Never emit tail calls"),
202  cl::init(false));
203 
204 static cl::opt<bool> StackSymbolOrdering("stack-symbol-ordering",
205  cl::desc("Order local stack symbols."),
206  cl::init(true));
207 
208 static cl::opt<unsigned>
209  OverrideStackAlignment("stack-alignment",
210  cl::desc("Override default stack alignment"),
211  cl::init(0));
212 
213 static cl::opt<bool>
214  StackRealign("stackrealign",
215  cl::desc("Force align the stack to the minimum alignment"),
216  cl::init(false));
217 
218 static cl::opt<std::string> TrapFuncName(
219  "trap-func", cl::Hidden,
220  cl::desc("Emit a call to trap function rather than a trap instruction"),
221  cl::init(""));
222 
223 static cl::opt<bool> UseCtors("use-ctors",
224  cl::desc("Use .ctors instead of .init_array."),
225  cl::init(false));
226 
227 static cl::opt<bool> RelaxELFRelocations(
228  "relax-elf-relocations",
229  cl::desc("Emit GOTPCRELX/REX_GOTPCRELX instead of GOTPCREL on x86-64 ELF"),
230  cl::init(false));
231 
232 static cl::opt<bool> DataSections("data-sections",
233  cl::desc("Emit data into separate sections"),
234  cl::init(false));
235 
236 static cl::opt<bool>
237  FunctionSections("function-sections",
238  cl::desc("Emit functions into separate sections"),
239  cl::init(false));
240 
241 static cl::opt<bool> EmulatedTLS("emulated-tls",
242  cl::desc("Use emulated TLS model"),
243  cl::init(false));
244 
245 static cl::opt<bool>
246  UniqueSectionNames("unique-section-names",
247  cl::desc("Give unique names to every section"),
248  cl::init(true));
249 
250 static cl::opt<llvm::EABI>
251  EABIVersion("meabi", cl::desc("Set EABI type (default depends on triple):"),
254  "Triple default EABI version"),
255  clEnumValN(EABI::EABI4, "4", "EABI version 4"),
256  clEnumValN(EABI::EABI5, "5", "EABI version 5"),
257  clEnumValN(EABI::GNU, "gnu", "EABI GNU")));
258 
259 static cl::opt<DebuggerKind> DebuggerTuningOpt(
260  "debugger-tune", cl::desc("Tune debug info for a particular debugger"),
262  cl::values(clEnumValN(DebuggerKind::GDB, "gdb", "gdb"),
263  clEnumValN(DebuggerKind::LLDB, "lldb", "lldb"),
264  clEnumValN(DebuggerKind::SCE, "sce", "SCE targets (e.g. PS4)")));
265 
266 static cl::opt<bool> EnableStackSizeSection(
267  "stack-size-section",
268  cl::desc("Emit a section containing stack size metadata"), cl::init(false));
269 
270 static cl::opt<bool>
271  EnableAddrsig("addrsig", cl::desc("Emit an address-significance table"),
272  cl::init(false));
273 
274 // Common utility function tightly tied to the options listed here. Initializes
275 // a TargetOptions object with CodeGen flags and returns it.
276 static TargetOptions InitTargetOptionsFromCodeGenFlags() {
277  TargetOptions Options;
278  Options.AllowFPOpFusion = FuseFPOps;
279  Options.UnsafeFPMath = EnableUnsafeFPMath;
280  Options.NoInfsFPMath = EnableNoInfsFPMath;
281  Options.NoNaNsFPMath = EnableNoNaNsFPMath;
282  Options.NoSignedZerosFPMath = EnableNoSignedZerosFPMath;
283  Options.NoTrappingFPMath = EnableNoTrappingFPMath;
284  Options.FPDenormalMode = DenormalMode;
286  EnableHonorSignDependentRoundingFPMath;
287  if (FloatABIForCalls != FloatABI::Default)
288  Options.FloatABIType = FloatABIForCalls;
289  Options.NoZerosInBSS = DontPlaceZerosInBSS;
290  Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
291  Options.StackAlignmentOverride = OverrideStackAlignment;
292  Options.StackSymbolOrdering = StackSymbolOrdering;
293  Options.UseInitArray = !UseCtors;
294  Options.RelaxELFRelocations = RelaxELFRelocations;
295  Options.DataSections = DataSections;
296  Options.FunctionSections = FunctionSections;
297  Options.UniqueSectionNames = UniqueSectionNames;
298  Options.EmulatedTLS = EmulatedTLS;
299  Options.ExplicitEmulatedTLS = EmulatedTLS.getNumOccurrences() > 0;
300  Options.ExceptionModel = ExceptionModel;
301  Options.EmitStackSizeSection = EnableStackSizeSection;
302  Options.EmitAddrsig = EnableAddrsig;
303 
304  Options.MCOptions = InitMCTargetOptionsFromFlags();
305 
306  Options.ThreadModel = TMModel;
307  Options.EABIVersion = EABIVersion;
308  Options.DebuggerTuning = DebuggerTuningOpt;
309 
310  return Options;
311 }
312 
313 LLVM_ATTRIBUTE_UNUSED static std::string getCPUStr() {
314  // If user asked for the 'native' CPU, autodetect here. If autodection fails,
315  // this will set the CPU to an empty string which tells the target to
316  // pick a basic default.
317  if (MCPU == "native")
318  return sys::getHostCPUName();
319 
320  return MCPU;
321 }
322 
323 LLVM_ATTRIBUTE_UNUSED static std::string getFeaturesStr() {
324  SubtargetFeatures Features;
325 
326  // If user asked for the 'native' CPU, we need to autodetect features.
327  // This is necessary for x86 where the CPU might not support all the
328  // features the autodetected CPU name lists in the target. For example,
329  // not all Sandybridge processors support AVX.
330  if (MCPU == "native") {
331  StringMap<bool> HostFeatures;
332  if (sys::getHostCPUFeatures(HostFeatures))
333  for (auto &F : HostFeatures)
334  Features.AddFeature(F.first(), F.second);
335  }
336 
337  for (unsigned i = 0; i != MAttrs.size(); ++i)
338  Features.AddFeature(MAttrs[i]);
339 
340  return Features.getString();
341 }
342 
343 LLVM_ATTRIBUTE_UNUSED static std::vector<std::string> getFeatureList() {
344  SubtargetFeatures Features;
345 
346  // If user asked for the 'native' CPU, we need to autodetect features.
347  // This is necessary for x86 where the CPU might not support all the
348  // features the autodetected CPU name lists in the target. For example,
349  // not all Sandybridge processors support AVX.
350  if (MCPU == "native") {
351  StringMap<bool> HostFeatures;
352  if (sys::getHostCPUFeatures(HostFeatures))
353  for (auto &F : HostFeatures)
354  Features.AddFeature(F.first(), F.second);
355  }
356 
357  for (unsigned i = 0; i != MAttrs.size(); ++i)
358  Features.AddFeature(MAttrs[i]);
359 
360  return Features.getFeatures();
361 }
362 
363 /// Set function attributes of functions in Module M based on CPU,
364 /// Features, and command line flags.
365 LLVM_ATTRIBUTE_UNUSED static void
366 setFunctionAttributes(StringRef CPU, StringRef Features, Module &M) {
367  for (auto &F : M) {
368  auto &Ctx = F.getContext();
369  AttributeList Attrs = F.getAttributes();
370  AttrBuilder NewAttrs;
371 
372  if (!CPU.empty())
373  NewAttrs.addAttribute("target-cpu", CPU);
374  if (!Features.empty())
375  NewAttrs.addAttribute("target-features", Features);
376  if (FramePointerUsage.getNumOccurrences() > 0) {
377  if (FramePointerUsage == llvm::FramePointer::All)
378  NewAttrs.addAttribute("frame-pointer", "all");
379  else if (FramePointerUsage == llvm::FramePointer::NonLeaf)
380  NewAttrs.addAttribute("frame-pointer", "non-leaf");
381  else if (FramePointerUsage == llvm::FramePointer::None)
382  NewAttrs.addAttribute("frame-pointer", "none");
383  }
384  if (DisableTailCalls.getNumOccurrences() > 0)
385  NewAttrs.addAttribute("disable-tail-calls",
386  toStringRef(DisableTailCalls));
387  if (StackRealign)
388  NewAttrs.addAttribute("stackrealign");
389 
390  if (TrapFuncName.getNumOccurrences() > 0)
391  for (auto &B : F)
392  for (auto &I : B)
393  if (auto *Call = dyn_cast<CallInst>(&I))
394  if (const auto *F = Call->getCalledFunction())
395  if (F->getIntrinsicID() == Intrinsic::debugtrap ||
396  F->getIntrinsicID() == Intrinsic::trap)
397  Call->addAttribute(
399  Attribute::get(Ctx, "trap-func-name", TrapFuncName));
400 
401  // Let NewAttrs override Attrs.
402  F.setAttributes(
403  Attrs.addAttributes(Ctx, AttributeList::FunctionIndex, NewAttrs));
404  }
405 }
unsigned StackSymbolOrdering
StackSymbolOrdering - When true, this will allow CodeGen to order the local stack symbols (for code s...
const NoneType None
Definition: None.h:23
unsigned NoTrappingFPMath
NoTrappingFPMath - This flag is enabled when the -enable-no-trapping-fp-math is specified on the comm...
MCTargetOptions MCOptions
Machine level options.
This class represents lattice values for constants.
Definition: AllocatorList.h:23
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:65
EABI EABIVersion
EABIVersion - This flag specifies the EABI version.
unsigned DataSections
Emit data into separate sections.
setjmp/longjmp based exceptions
std::string getString() const
Returns features as a string.
F(f)
AttrBuilder & addAttribute(Attribute::AttrKind Val)
Add an attribute to the builder.
ThreadModel::Model ThreadModel
ThreadModel - This flag specifies the type of threading model to assume for things like atomics...
ExceptionHandling ExceptionModel
What exception model to use.
LLVM_NODISCARD bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:126
void AddFeature(StringRef String, bool Enable=true)
Adds Features.
unsigned NoNaNsFPMath
NoNaNsFPMath - This flag is enabled when the -enable-no-nans-fp-math flag is specified on the command...
unsigned FunctionSections
Emit functions into separate sections.
unsigned UniqueSectionNames
constexpr char Attrs[]
Key for Kernel::Metadata::mAttrs.
static Reloc::Model getRelocModel(Optional< Reloc::Model > RM)
WebAssembly Exception Handling.
DebuggerKind DebuggerTuning
Which debugger to tune for.
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:427
const std::vector< std::string > & getFeatures() const
Returns the vector of individual subtarget features.
unsigned UnsafeFPMath
UnsafeFPMath - This flag is enabled when the -enable-unsafe-fp-math flag is specified on the command ...
FPOpFusion::FPOpFusionMode AllowFPOpFusion
AllowFPOpFusion - This flag is set by the -fuse-fp-ops=xxx option.
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
unsigned ExplicitEmulatedTLS
Whether -emulated-tls or -no-emulated-tls is set.
ValuesClass values(OptsTy... Options)
Helper to build a ValuesClass by forwarding a variable number of arguments as an initializer list to ...
Definition: CommandLine.h:647
unsigned EmitStackSizeSection
Emit section containing metadata on function stack sizes.
#define LLVM_ATTRIBUTE_UNUSED
Definition: Compiler.h:159
unsigned GuaranteedTailCallOpt
GuaranteedTailCallOpt - This flag is enabled when -tailcallopt is specified on the commandline...
unsigned NoInfsFPMath
NoInfsFPMath - This flag is enabled when the -enable-no-infs-fp-math flag is specified on the command...
FPDenormal::DenormalMode FPDenormalMode
FPDenormalMode - This flags specificies which denormal numbers the code is permitted to require...
unsigned NoZerosInBSS
NoZerosInBSS - By default some codegens place zero-initialized data to .bss section.
StringRef toStringRef(bool B)
Construct a string ref from a boolean.
Definition: StringExtras.h:52
FileType
Defines the file type this file represents.
Definition: InterfaceFile.h:65
unsigned UseInitArray
UseInitArray - Use .init_array instead of .ctors for static constructors.
Module.h This file contains the declarations for the Module class.
unsigned EmitAddrsig
Emit address-significance table.
unsigned StackAlignmentOverride
StackAlignmentOverride - Override default stack alignment for target.
Manages the enabling and disabling of subtarget specific features.
unsigned EmulatedTLS
EmulatedTLS - This flag enables emulated TLS model, using emutls function in the runtime library...
unsigned RelaxELFRelocations
#define clEnumValN(ENUMVAL, FLAGNAME, DESC)
Definition: CommandLine.h:622
StringRef getHostCPUName()
getHostCPUName - Get the LLVM name for the host CPU.
Definition: Host.cpp:1174
No exception support.
Windows Exception Handling.
#define I(x, y, z)
Definition: MD5.cpp:58
static Attribute get(LLVMContext &Context, AttrKind Kind, uint64_t Val=0)
Return a uniquified Attribute object.
Definition: Attributes.cpp:80
LLVM_NODISCARD AttributeList addAttributes(LLVMContext &C, unsigned Index, const AttrBuilder &B) const
Add attributes to the attribute set at the given index.
unsigned HonorSignDependentRoundingFPMathOption
HonorSignDependentRoundingFPMath - This returns true when the -enable-sign-dependent-rounding-fp-math...
unsigned NoSignedZerosFPMath
NoSignedZerosFPMath - This flag is enabled when the -enable-no-signed-zeros-fp-math is specified on t...
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
bool getHostCPUFeatures(StringMap< bool > &Features)
getHostCPUFeatures - Get the LLVM names for the host CPU features.
Definition: Host.cpp:1461
DWARF-like instruction based exceptions.
FloatABI::ABIType FloatABIType
FloatABIType - This setting is set by -float-abi=xxx option is specfied on the command line...