1 //===-- llvm/Target/TargetOptions.h - Target Options ------------*- 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 defines command line option flags that are shared across various
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_TARGET_TARGETOPTIONS_H
16 #define LLVM_TARGET_TARGETOPTIONS_H
19 /// PrintMachineCode - This flag is enabled when the -print-machineinstrs
20 /// option is specified on the command line, and should enable debugging
21 /// output from the code generator.
22 extern bool PrintMachineCode;
24 /// NoFramePointerElim - This flag is enabled when the -disable-fp-elim is
25 /// specified on the command line. If the target supports the frame pointer
26 /// elimination optimization, this option should disable it.
27 extern bool NoFramePointerElim;
29 /// LessPreciseFPMAD - This flag is enabled when the
30 /// -enable-fp-mad is specified on the command line. When this flag is off
31 /// (the default), the code generator is not allowed to generate mad
32 /// (multiply add) if the result is "less precise" than doing those operations
34 extern bool LessPreciseFPMADOption;
35 extern bool LessPreciseFPMAD();
37 /// NoExcessFPPrecision - This flag is enabled when the
38 /// -disable-excess-fp-precision flag is specified on the command line. When
39 /// this flag is off (the default), the code generator is allowed to produce
40 /// results that are "more precise" than IEEE allows. This includes use of
41 /// FMA-like operations and use of the X86 FP registers without rounding all
43 extern bool NoExcessFPPrecision;
45 /// UnsafeFPMath - This flag is enabled when the
46 /// -enable-unsafe-fp-math flag is specified on the command line. When
47 /// this flag is off (the default), the code generator is not allowed to
48 /// produce results that are "less precise" than IEEE allows. This includes
49 /// use of X86 instructions like FSIN and FCOS instead of libcalls.
50 /// UnsafeFPMath implies FiniteOnlyFPMath and LessPreciseFPMAD.
51 extern bool UnsafeFPMath;
53 /// FiniteOnlyFPMath - This returns true when the -enable-finite-only-fp-math
54 /// option is specified on the command line. If this returns false (default),
55 /// the code generator is not allowed to assume that FP arithmetic arguments
56 /// and results are never NaNs or +-Infs.
57 extern bool FiniteOnlyFPMathOption;
58 extern bool FiniteOnlyFPMath();
60 /// HonorSignDependentRoundingFPMath - This returns true when the
61 /// -enable-sign-dependent-rounding-fp-math is specified. If this returns
62 /// false (the default), the code generator is allowed to assume that the
63 /// rounding behavior is the default (round-to-zero for all floating point to
64 /// integer conversions, and round-to-nearest for all other arithmetic
65 /// truncations). If this is enabled (set to true), the code generator must
66 /// assume that the rounding mode may dynamically change.
67 extern bool HonorSignDependentRoundingFPMathOption;
68 extern bool HonorSignDependentRoundingFPMath();
70 /// UseSoftFloat - This flag is enabled when the -soft-float flag is specified
71 /// on the command line. When this flag is on, the code generator will
72 /// generate libcalls to the software floating point library instead of
73 /// target FP instructions.
74 extern bool UseSoftFloat;
76 /// FloatABIType - This setting is set by -float-abi=xxx option is specfied
77 /// on the command line. This setting may either be Default, Soft, or Hard.
78 /// Default selects the target's default behavior. Soft selects the ABI for
79 /// UseSoftFloat, but does not inidcate that FP hardware may not be used.
80 /// Such a combination is unfortunately popular (e.g. arm-apple-darwin).
81 /// Hard presumes that the normal FP ABI is used.
82 extern FloatABI::ABIType FloatABIType;
84 /// NoZerosInBSS - By default some codegens place zero-initialized data to
85 /// .bss section. This flag disables such behaviour (necessary, e.g. for
86 /// crt*.o compiling).
87 extern bool NoZerosInBSS;
89 /// ExceptionHandling - This flag indicates that exception information should
91 extern bool ExceptionHandling;
93 /// UnwindTablesMandatory - This flag indicates that unwind tables should
94 /// be emitted for all functions.
95 extern bool UnwindTablesMandatory;
97 /// PerformTailCallOpt - This flag is enabled when -tailcallopt is specified
98 /// on the commandline. When the flag is on, the target will perform tail call
99 /// optimization (pop the caller's stack) providing it supports it.
100 extern bool PerformTailCallOpt;
102 /// StackAlignment - Override default stack alignment for target.
103 extern unsigned StackAlignment;
105 /// RealignStack - This flag indicates, whether stack should be automatically
106 /// realigned, if needed.
107 extern bool RealignStack;
109 /// DisableJumpTables - This flag indicates jump tables should not be
111 extern bool DisableJumpTables;
113 /// EnableFastISel - This flag enables fast-path instruction selection
114 /// which trades away generated code quality in favor of reducing
116 extern bool EnableFastISel;
118 /// StrongPHIElim - This flag enables more aggressive PHI elimination
119 /// wth earlier copy coalescing.
120 extern bool StrongPHIElim;
122 } // End llvm namespace