1 //===-- CommandFlags.h - Command Line Flags Interface -----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
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
12 // flag duplication.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_CODEGEN_COMMANDFLAGS_H
17 #define LLVM_CODEGEN_COMMANDFLAGS_H
18 
19 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
20 #include "llvm/Support/CodeGen.h"
21 #include "llvm/Support/CommandLine.h"
22 #include "llvm/Target/TargetMachine.h"
23 #include "llvm/Target/TargetOptions.h"
24 #include <string>
25 using namespace llvm;
26 
27 cl::opt<std::string>
28 MArch("march", cl::desc("Architecture to generate code for (see --version)"));
29 
30 cl::opt<std::string>
31 MCPU("mcpu",
32      cl::desc("Target a specific cpu type (-mcpu=help for details)"),
33      cl::value_desc("cpu-name"),
34      cl::init(""));
35 
36 cl::list<std::string>
37 MAttrs("mattr",
38        cl::CommaSeparated,
39        cl::desc("Target specific attributes (-mattr=help for details)"),
40        cl::value_desc("a1,+a2,-a3,..."));
41 
42 cl::opt<Reloc::Model>
43 RelocModel("relocation-model",
44            cl::desc("Choose relocation model"),
45            cl::init(Reloc::Default),
46            cl::values(
47               clEnumValN(Reloc::Default, "default",
48                       "Target default relocation model"),
49               clEnumValN(Reloc::Static, "static",
50                       "Non-relocatable code"),
51               clEnumValN(Reloc::PIC_, "pic",
52                       "Fully relocatable, position independent code"),
53               clEnumValN(Reloc::DynamicNoPIC, "dynamic-no-pic",
54                       "Relocatable external references, non-relocatable code"),
55               clEnumValEnd));
56 
57 cl::opt<ThreadModel::Model>
58 TMModel("thread-model",
59         cl::desc("Choose threading model"),
60         cl::init(ThreadModel::POSIX),
61         cl::values(clEnumValN(ThreadModel::POSIX, "posix",
62                               "POSIX thread model"),
63                    clEnumValN(ThreadModel::Single, "single",
64                               "Single thread model"),
65                    clEnumValEnd));
66 
67 cl::opt<llvm::CodeModel::Model>
68 CMModel("code-model",
69         cl::desc("Choose code model"),
70         cl::init(CodeModel::Default),
71         cl::values(clEnumValN(CodeModel::Default, "default",
72                               "Target default code model"),
73                    clEnumValN(CodeModel::Small, "small",
74                               "Small code model"),
75                    clEnumValN(CodeModel::Kernel, "kernel",
76                               "Kernel code model"),
77                    clEnumValN(CodeModel::Medium, "medium",
78                               "Medium code model"),
79                    clEnumValN(CodeModel::Large, "large",
80                               "Large code model"),
81                    clEnumValEnd));
82 
83 cl::opt<TargetMachine::CodeGenFileType>
84 FileType("filetype", cl::init(TargetMachine::CGFT_AssemblyFile),
85   cl::desc("Choose a file type (not all types are supported by all targets):"),
86   cl::values(
87              clEnumValN(TargetMachine::CGFT_AssemblyFile, "asm",
88                         "Emit an assembly ('.s') file"),
89              clEnumValN(TargetMachine::CGFT_ObjectFile, "obj",
90                         "Emit a native object ('.o') file"),
91              clEnumValN(TargetMachine::CGFT_Null, "null",
92                         "Emit nothing, for performance testing"),
93              clEnumValEnd));
94 
95 cl::opt<bool>
96 EnableFPMAD("enable-fp-mad",
97             cl::desc("Enable less precise MAD instructions to be generated"),
98             cl::init(false));
99 
100 cl::opt<bool>
101 DisableFPElim("disable-fp-elim",
102               cl::desc("Disable frame pointer elimination optimization"),
103               cl::init(false));
104 
105 cl::opt<bool>
106 EnableUnsafeFPMath("enable-unsafe-fp-math",
107                 cl::desc("Enable optimizations that may decrease FP precision"),
108                 cl::init(false));
109 
110 cl::opt<bool>
111 EnableNoInfsFPMath("enable-no-infs-fp-math",
112                 cl::desc("Enable FP math optimizations that assume no +-Infs"),
113                 cl::init(false));
114 
115 cl::opt<bool>
116 EnableNoNaNsFPMath("enable-no-nans-fp-math",
117                    cl::desc("Enable FP math optimizations that assume no NaNs"),
118                    cl::init(false));
119 
120 cl::opt<bool>
121 EnableHonorSignDependentRoundingFPMath("enable-sign-dependent-rounding-fp-math",
122       cl::Hidden,
123       cl::desc("Force codegen to assume rounding mode can change dynamically"),
124       cl::init(false));
125 
126 cl::opt<bool>
127 GenerateSoftFloatCalls("soft-float",
128                     cl::desc("Generate software floating point library calls"),
129                     cl::init(false));
130 
131 cl::opt<llvm::FloatABI::ABIType>
132 FloatABIForCalls("float-abi",
133                  cl::desc("Choose float ABI type"),
134                  cl::init(FloatABI::Default),
135                  cl::values(
136                      clEnumValN(FloatABI::Default, "default",
137                                 "Target default float ABI type"),
138                      clEnumValN(FloatABI::Soft, "soft",
139                                 "Soft float ABI (implied by -soft-float)"),
140                      clEnumValN(FloatABI::Hard, "hard",
141                                 "Hard float ABI (uses FP registers)"),
142                      clEnumValEnd));
143 
144 cl::opt<llvm::FPOpFusion::FPOpFusionMode>
145 FuseFPOps("fp-contract",
146           cl::desc("Enable aggressive formation of fused FP ops"),
147           cl::init(FPOpFusion::Standard),
148           cl::values(
149               clEnumValN(FPOpFusion::Fast, "fast",
150                          "Fuse FP ops whenever profitable"),
151               clEnumValN(FPOpFusion::Standard, "on",
152                          "Only fuse 'blessed' FP ops."),
153               clEnumValN(FPOpFusion::Strict, "off",
154                          "Only fuse FP ops when the result won't be effected."),
155               clEnumValEnd));
156 
157 cl::opt<bool>
158 DontPlaceZerosInBSS("nozero-initialized-in-bss",
159               cl::desc("Don't place zero-initialized symbols into bss section"),
160               cl::init(false));
161 
162 cl::opt<bool>
163 EnableGuaranteedTailCallOpt("tailcallopt",
164   cl::desc("Turn fastcc calls into tail calls by (potentially) changing ABI."),
165   cl::init(false));
166 
167 cl::opt<bool>
168 DisableTailCalls("disable-tail-calls",
169                  cl::desc("Never emit tail calls"),
170                  cl::init(false));
171 
172 cl::opt<unsigned>
173 OverrideStackAlignment("stack-alignment",
174                        cl::desc("Override default stack alignment"),
175                        cl::init(0));
176 
177 cl::opt<std::string>
178 TrapFuncName("trap-func", cl::Hidden,
179         cl::desc("Emit a call to trap function rather than a trap instruction"),
180         cl::init(""));
181 
182 cl::opt<bool>
183 EnablePIE("enable-pie",
184           cl::desc("Assume the creation of a position independent executable."),
185           cl::init(false));
186 
187 cl::opt<bool>
188 UseCtors("use-ctors",
189              cl::desc("Use .ctors instead of .init_array."),
190              cl::init(false));
191 
192 cl::opt<std::string> StopAfter("stop-after",
193                             cl::desc("Stop compilation after a specific pass"),
194                             cl::value_desc("pass-name"),
195                                       cl::init(""));
196 cl::opt<std::string> StartAfter("start-after",
197                           cl::desc("Resume compilation after a specific pass"),
198                           cl::value_desc("pass-name"),
199                           cl::init(""));
200 
201 cl::opt<bool> DataSections("data-sections",
202                            cl::desc("Emit data into separate sections"),
203                            cl::init(false));
204 
205 cl::opt<bool>
206 FunctionSections("function-sections",
207                  cl::desc("Emit functions into separate sections"),
208                  cl::init(false));
209 
210 cl::opt<bool> UniqueSectionNames("unique-section-names",
211                                  cl::desc("Give unique names to every section"),
212                                  cl::init(true));
213 
214 cl::opt<llvm::JumpTable::JumpTableType>
215 JTableType("jump-table-type",
216           cl::desc("Choose the type of Jump-Instruction Table for jumptable."),
217           cl::init(JumpTable::Single),
218           cl::values(
219               clEnumValN(JumpTable::Single, "single",
220                          "Create a single table for all jumptable functions"),
221               clEnumValN(JumpTable::Arity, "arity",
222                          "Create one table per number of parameters."),
223               clEnumValN(JumpTable::Simplified, "simplified",
224                          "Create one table per simplified function type."),
225               clEnumValN(JumpTable::Full, "full",
226                          "Create one table per unique function type."),
227               clEnumValEnd));
228 
229 cl::opt<bool>
230 FCFI("fcfi",
231      cl::desc("Apply forward-edge control-flow integrity"),
232      cl::init(false));
233 
234 cl::opt<llvm::CFIntegrity>
235 CFIType("cfi-type",
236         cl::desc("Choose the type of Control-Flow Integrity check to add"),
237         cl::init(CFIntegrity::Sub),
238         cl::values(
239             clEnumValN(CFIntegrity::Sub, "sub",
240                        "Subtract the pointer from the table base, then mask."),
241             clEnumValN(CFIntegrity::Ror, "ror",
242                        "Use rotate to check the offset from a table base."),
243             clEnumValN(CFIntegrity::Add, "add",
244                        "Mask out the high bits and add to an aligned base."),
245             clEnumValEnd));
246 
247 cl::opt<bool>
248 CFIEnforcing("cfi-enforcing",
249              cl::desc("Enforce CFI or pass the violation to a function."),
250              cl::init(false));
251 
252 // Note that this option is linked to the cfi-enforcing option above: if
253 // cfi-enforcing is set, then the cfi-func-name option is entirely ignored. If
254 // cfi-enforcing is false and no cfi-func-name is set, then a default function
255 // will be generated that ignores all CFI violations. The expected signature for
256 // functions called with CFI violations is
257 //
258 // void (i8*, i8*)
259 //
260 // The first pointer is a C string containing the name of the function in which
261 // the violation occurs, and the second pointer is the pointer that violated
262 // CFI.
263 cl::opt<std::string>
264 CFIFuncName("cfi-func-name", cl::desc("The name of the CFI function to call"),
265             cl::init(""));
266 
267 // Common utility function tightly tied to the options listed here. Initializes
268 // a TargetOptions object with CodeGen flags and returns it.
InitTargetOptionsFromCodeGenFlags()269 static inline TargetOptions InitTargetOptionsFromCodeGenFlags() {
270   TargetOptions Options;
271   Options.LessPreciseFPMADOption = EnableFPMAD;
272   Options.NoFramePointerElim = DisableFPElim;
273   Options.AllowFPOpFusion = FuseFPOps;
274   Options.UnsafeFPMath = EnableUnsafeFPMath;
275   Options.NoInfsFPMath = EnableNoInfsFPMath;
276   Options.NoNaNsFPMath = EnableNoNaNsFPMath;
277   Options.HonorSignDependentRoundingFPMathOption =
278       EnableHonorSignDependentRoundingFPMath;
279   Options.UseSoftFloat = GenerateSoftFloatCalls;
280   if (FloatABIForCalls != FloatABI::Default)
281     Options.FloatABIType = FloatABIForCalls;
282   Options.NoZerosInBSS = DontPlaceZerosInBSS;
283   Options.GuaranteedTailCallOpt = EnableGuaranteedTailCallOpt;
284   Options.DisableTailCalls = DisableTailCalls;
285   Options.StackAlignmentOverride = OverrideStackAlignment;
286   Options.TrapFuncName = TrapFuncName;
287   Options.PositionIndependentExecutable = EnablePIE;
288   Options.UseInitArray = !UseCtors;
289   Options.DataSections = DataSections;
290   Options.FunctionSections = FunctionSections;
291   Options.UniqueSectionNames = UniqueSectionNames;
292 
293   Options.MCOptions = InitMCTargetOptionsFromFlags();
294   Options.JTType = JTableType;
295   Options.FCFI = FCFI;
296   Options.CFIType = CFIType;
297   Options.CFIEnforcing = CFIEnforcing;
298   Options.CFIFuncName = CFIFuncName;
299 
300   Options.ThreadModel = TMModel;
301 
302   return Options;
303 }
304 
305 #endif
306