1 //===- subzero/src/IceBuildDefs.h - Translator build defines ----*- C++ -*-===//
2 //
3 // The Subzero Code Generator
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// \brief Define the Ice::BuildDefs namespace
12 //===----------------------------------------------------------------------===//
13
14 #ifndef SUBZERO_SRC_ICEBUILDDEFS_H
15 #define SUBZERO_SRC_ICEBUILDDEFS_H
16
17 namespace Ice {
18 /// \brief Defines constexpr functions that express various Subzero build
19 /// system defined values.
20 ///
21 /// These resulting constexpr functions allow code to in effect be
22 /// conditionally compiled without having to do this using the older C++
23 /// preprocessor solution.
24
25 /** \verbatim
26
27 For example whenever the value of FEATURE_SUPPORTED is needed, instead
28 of (except in these constexpr functions):
29
30 #if FEATURE_SUPPORTED ...
31 ...
32 #endif
33
34 We can have:
35
36 namespace Ice {
37 namespace BuildDefs {
38
39 // Use this form when FEATURE_SUPPORTED is guaranteed to be defined on the
40 // C++ compiler command line as 0 or 1.
41 constexpr bool hasFeature() { return FEATURE_SUPPORTED; }
42
43 or
44
45 // Use this form when FEATURE_SUPPORTED may not necessarily be defined on
46 // the C++ compiler command line.
47 constexpr bool hasFeature() {
48 #if FEATURE_SUPPORTED
49 return true;
50 #else // !FEATURE_SUPPORTED
51 return false;
52 #endif // !FEATURE_SUPPORTED
53 }
54
55 ...} // end of namespace BuildDefs
56 } // end of namespace Ice
57
58
59 And later in the code:
60
61 if (Ice::BuildDefs::hasFeature() {
62 ...
63 }
64
65 \endverbatim
66
67 Since hasFeature() returns a constexpr, an optimizing compiler will know to
68 keep or discard the above fragment. In addition, the code will always be
69 looked at by the compiler which eliminates the problem with defines in that
70 if you don't build that variant, you don't even know if the code would
71 compile unless you build with that variant.
72
73 **/
74
75 namespace BuildDefs {
76
77 // The ALLOW_* etc. symbols must be #defined to zero or non-zero.
78 /// Return true if ALLOW_DUMP is defined as a non-zero value
dump()79 constexpr bool dump() { return ALLOW_DUMP; }
80 /// Return true if ALLOW_TIMERS is defined as a non-zero value
timers()81 constexpr bool timers() { return ALLOW_TIMERS; }
82 /// Return true if ALLOW_LLVM_CL is defined as a non-zero value
83 // TODO(stichnot): this ALLOW_LLVM_CL is a TBD option which will
84 // allow for replacement of llvm:cl command line processor with a
85 // smaller footprint version for Subzero.
llvmCl()86 constexpr bool llvmCl() { return ALLOW_LLVM_CL; }
87 /// Return true if ALLOW_LLVM_IR is defined as a non-zero value
llvmIr()88 constexpr bool llvmIr() { return ALLOW_LLVM_IR; }
89 /// Return true if ALLOW_LLVM_IR_AS_INPUT is defined as a non-zero value
llvmIrAsInput()90 constexpr bool llvmIrAsInput() { return ALLOW_LLVM_IR_AS_INPUT; }
91 /// Return true if ALLOW_MINIMAL_BUILD is defined as a non-zero value
minimal()92 constexpr bool minimal() { return ALLOW_MINIMAL_BUILD; }
93 /// Return true if ALLOW_WASM is defined as a non-zero value
wasm()94 constexpr bool wasm() { return ALLOW_WASM; }
95
96 /// Return true if NDEBUG is defined
asserts()97 constexpr bool asserts() {
98 #ifdef NDEBUG
99 return false;
100 #else // !NDEBUG
101 return true;
102 #endif // !NDEBUG
103 }
104
105 /// Return true if PNACL_BROWSER_TRANSLATOR is defined
browser()106 constexpr bool browser() {
107 #if PNACL_BROWSER_TRANSLATOR
108 return true;
109 #else // !PNACL_BROWSER_TRANSLATOR
110 return false;
111 #endif // !PNACL_BROWSER_TRANSLATOR
112 }
113
114 /// Return true if ALLOW_EXTRA_VALIDATION is defined
extraValidation()115 constexpr bool extraValidation() {
116 #if ALLOW_EXTRA_VALIDATION
117 return true;
118 #else // !ALLOW_EXTRA_VALIDATION
119 return false;
120 #endif // !ALLOW_EXTRA_VALIDATION
121 }
122
123 } // end of namespace BuildDefs
124 } // end of namespace Ice
125
126 #endif // SUBZERO_SRC_ICEBUILDDEFS_H
127