1/* This D file is implicitly imported by all ImportC source files. 2 * It provides definitions for C compiler builtin functions and declarations. 3 * The purpose is to make it unnecessary to hardwire them into the compiler. 4 * As the leading double underscore suggests, this is for internal use only. 5 * 6 * Copyright: Copyright Digital Mars 2022 7 * License: $(HTTP www.boost.org/LICENSE_1_0.txt, Boost License 1.0). 8 * Authors: Walter Bright 9 * Source: $(DRUNTIMESRC __builtins.d) 10 */ 11 12 13module __builtins; 14 15/* gcc relies on internal __builtin_xxxx functions and templates to 16 * accomplish <stdarg.h>. D does the same thing with templates in core.stdc.stdarg. 17 * Here, we redirect the gcc builtin declarations to the equivalent 18 * ones in core.stdc.stdarg, thereby avoiding having to hardware them 19 * into the D compiler. 20 */ 21 22import core.stdc.stdarg; 23 24alias va_list = core.stdc.stdarg.va_list; 25 26version (Posix) 27{ 28 version (X86_64) 29 alias __va_list_tag = core.stdc.stdarg.__va_list_tag; 30} 31 32alias __builtin_va_start = core.stdc.stdarg.va_start; 33 34alias __builtin_va_end = core.stdc.stdarg.va_end; 35 36alias __builtin_va_copy = core.stdc.stdarg.va_copy; 37 38/* dmd's ImportC rewrites __builtin_va_arg into an instantiation of va_arg 39 */ 40alias va_arg = core.stdc.stdarg.va_arg; 41 42version (CRuntime_Microsoft) 43{ 44 //https://docs.microsoft.com/en-us/cpp/cpp/int8-int16-int32-int64?view=msvc-170 45 alias __int8 = byte; 46 alias __int16 = short; 47 alias __int32 = int; 48 alias __int64 = long; 49} 50 51/*********** floating point *************/ 52 53/* https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html 54 */ 55 56version (DigitalMars) 57{ 58 double __builtin_inf()() { return double.infinity; } 59 float __builtin_inff()() { return float.infinity; } 60 real __builtin_infl()() { return real.infinity; } 61 62 alias __builtin_huge_val = __builtin_inf; 63 alias __builtin_huge_valf = __builtin_inff; 64 alias __builtin_huge_vall = __builtin_infl; 65 66 import core.stdc.math; 67 68 alias __builtin_fabs = core.stdc.math.fabs; 69 alias __builtin_fabsf = core.stdc.math.fabsf; 70 alias __builtin_fabsl = core.stdc.math.fabsl; 71 72 ushort __builtin_bswap16()(ushort value) 73 { 74 import core.bitop; 75 return core.bitop.byteswap(value); 76 } 77 78 uint __builtin_bswap32()(uint value) 79 { 80 import core.bitop; 81 return core.bitop.bswap(value); 82 } 83 84 ulong __builtin_bswap64()(ulong value) 85 { 86 import core.bitop; 87 return core.bitop.bswap(value); 88 } 89 90 // Stub these out to no-ops 91 int __builtin_constant_p(T)(T exp) { return 0; } // should be something like __traits(compiles, enum X = expr) 92 long __builtin_expect()(long exp, long c) { return exp; } 93 void* __builtin_assume_aligned()(const void* p, size_t align_, ...) { return cast(void*)p; } 94 95 // https://releases.llvm.org/13.0.0/tools/clang/docs/LanguageExtensions.html#builtin-assume 96 void __builtin_assume(T)(lazy T arg) { } 97 98 /* Header on macOS for arm64 references this. 99 * Don't need to implement it, it just needs to compile 100 */ 101 align (16) struct __uint128_t 102 { 103 ulong a, b; 104 } 105} 106