xref: /freebsd-src/contrib/llvm-project/compiler-rt/lib/builtins/int_lib.h (revision 71daeec70a15871cfc0071321cd1e819399aa911)
1 //===-- int_lib.h - configuration header for compiler-rt  -----------------===//
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 is a configuration header for compiler-rt.
10 // This file is not part of the interface of this library.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef INT_LIB_H
15 #define INT_LIB_H
16 
17 // Assumption: Signed integral is 2's complement.
18 // Assumption: Right shift of signed negative is arithmetic shift.
19 // Assumption: Endianness is little or big (not mixed).
20 
21 // ABI macro definitions
22 
23 #if __ARM_EABI__
24 #if defined(COMPILER_RT_ARMHF_TARGET) || (!defined(__clang__) && \
25     defined(__GNUC__) && (__GNUC__ < 4 || __GNUC__ == 4 && __GNUC_MINOR__ < 5))
26 // The pcs attribute was introduced in GCC 4.5.0
27 #define COMPILER_RT_ABI
28 #else
29 #define COMPILER_RT_ABI __attribute__((__pcs__("aapcs")))
30 #endif
31 #else
32 #define COMPILER_RT_ABI
33 #endif
34 
35 #define AEABI_RTABI __attribute__((__pcs__("aapcs")))
36 
37 #if defined(_MSC_VER) && !defined(__clang__)
38 #define ALWAYS_INLINE __forceinline
39 #define NOINLINE __declspec(noinline)
40 #define NORETURN __declspec(noreturn)
41 #define UNUSED
42 #else
43 #define ALWAYS_INLINE __attribute__((always_inline))
44 #define NOINLINE __attribute__((noinline))
45 #define NORETURN __attribute__((noreturn))
46 #define UNUSED __attribute__((unused))
47 #endif
48 
49 #define STR(a) #a
50 #define XSTR(a) STR(a)
51 #define SYMBOL_NAME(name) XSTR(__USER_LABEL_PREFIX__) #name
52 
53 #if defined(__ELF__) || defined(__MINGW32__) || defined(__wasm__) ||           \
54     defined(_AIX)
55 #define COMPILER_RT_ALIAS(name, aliasname) \
56   COMPILER_RT_ABI __typeof(name) aliasname __attribute__((__alias__(#name)));
57 #elif defined(__APPLE__)
58 #if defined(VISIBILITY_HIDDEN)
59 #define COMPILER_RT_ALIAS_VISIBILITY(name) \
60   __asm__(".private_extern " SYMBOL_NAME(name));
61 #else
62 #define COMPILER_RT_ALIAS_VISIBILITY(name)
63 #endif
64 #define COMPILER_RT_ALIAS(name, aliasname) \
65   __asm__(".globl " SYMBOL_NAME(aliasname)); \
66   COMPILER_RT_ALIAS_VISIBILITY(aliasname) \
67   __asm__(SYMBOL_NAME(aliasname) " = " SYMBOL_NAME(name)); \
68   COMPILER_RT_ABI __typeof(name) aliasname;
69 #elif defined(_WIN32)
70 #define COMPILER_RT_ALIAS(name, aliasname)
71 #else
72 #error Unsupported target
73 #endif
74 
75 #if defined(__NetBSD__) && (defined(_KERNEL) || defined(_STANDALONE))
76 //
77 // Kernel and boot environment can't use normal headers,
78 // so use the equivalent system headers.
79 //
80 #include <machine/limits.h>
81 #include <sys/stdint.h>
82 #include <sys/types.h>
83 #else
84 // Include the standard compiler builtin headers we use functionality from.
85 #include <float.h>
86 #include <limits.h>
87 #include <stdbool.h>
88 #include <stdint.h>
89 #endif
90 
91 // Include the commonly used internal type definitions.
92 #include "int_types.h"
93 
94 // Include internal utility function declarations.
95 #include "int_util.h"
96 
97 /*
98  * Workaround for LLVM bug 11663.  Prevent endless recursion in
99  * __c?zdi2(), where calls to __builtin_c?z() are expanded to
100  * __c?zdi2() instead of __c?zsi2().
101  *
102  * Instead of placing this workaround in c?zdi2.c, put it in this
103  * global header to prevent other C files from making the detour
104  * through __c?zdi2() as well.
105  *
106  * This problem has been observed on FreeBSD for sparc64 and
107  * mips64 with GCC 4.2.1, and for riscv with GCC 5.2.0.
108  * Presumably it's any version of GCC, and targeting an arch that
109  * does not have dedicated bit counting instructions.
110  */
111 #if defined(__FreeBSD__) && (defined(__sparc64__) || \
112     defined(__mips_n32) || defined(__mips_n64) || defined(__mips_o64) || \
113     defined(__riscv))
114 si_int __clzsi2(si_int);
115 si_int __ctzsi2(si_int);
116 #define	__builtin_clz __clzsi2
117 #define	__builtin_ctz __ctzsi2
118 #endif /* FreeBSD && (sparc64 || mips_n32 || mips_n64 || mips_o64 || riscv) */
119 
120 COMPILER_RT_ABI int __paritysi2(si_int a);
121 COMPILER_RT_ABI int __paritydi2(di_int a);
122 
123 COMPILER_RT_ABI di_int __divdi3(di_int a, di_int b);
124 COMPILER_RT_ABI si_int __divsi3(si_int a, si_int b);
125 COMPILER_RT_ABI su_int __udivsi3(su_int n, su_int d);
126 
127 COMPILER_RT_ABI su_int __udivmodsi4(su_int a, su_int b, su_int *rem);
128 COMPILER_RT_ABI du_int __udivmoddi4(du_int a, du_int b, du_int *rem);
129 #ifdef CRT_HAS_128BIT
130 COMPILER_RT_ABI int __clzti2(ti_int a);
131 COMPILER_RT_ABI tu_int __udivmodti4(tu_int a, tu_int b, tu_int *rem);
132 #endif
133 
134 // Definitions for builtins unavailable on MSVC
135 #if defined(_MSC_VER) && !defined(__clang__)
136 #include <intrin.h>
137 
138 int __inline __builtin_ctz(uint32_t value) {
139   unsigned long trailing_zero = 0;
140   if (_BitScanForward(&trailing_zero, value))
141     return trailing_zero;
142   return 32;
143 }
144 
145 int __inline __builtin_clz(uint32_t value) {
146   unsigned long leading_zero = 0;
147   if (_BitScanReverse(&leading_zero, value))
148     return 31 - leading_zero;
149   return 32;
150 }
151 
152 #if defined(_M_ARM) || defined(_M_X64)
153 int __inline __builtin_clzll(uint64_t value) {
154   unsigned long leading_zero = 0;
155   if (_BitScanReverse64(&leading_zero, value))
156     return 63 - leading_zero;
157   return 64;
158 }
159 #else
160 int __inline __builtin_clzll(uint64_t value) {
161   if (value == 0)
162     return 64;
163   uint32_t msh = (uint32_t)(value >> 32);
164   uint32_t lsh = (uint32_t)(value & 0xFFFFFFFF);
165   if (msh != 0)
166     return __builtin_clz(msh);
167   return 32 + __builtin_clz(lsh);
168 }
169 #endif
170 
171 #define __builtin_clzl __builtin_clzll
172 #endif // defined(_MSC_VER) && !defined(__clang__)
173 
174 #endif // INT_LIB_H
175