1/* Shared HTM header. Emulate transactional execution facility intrinsics for
2 compilers and assemblers that do not support the intrinsics and instructions
3 yet.
4
5 Copyright (C) 2015-2024 Free Software Foundation, Inc.
6 This file is part of the GNU C Library.
7
8 The GNU C Library is free software; you can redistribute it and/or
9 modify it under the terms of the GNU Lesser General Public
10 License as published by the Free Software Foundation; either
11 version 2.1 of the License, or (at your option) any later version.
12
13 The GNU C Library is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
17
18 You should have received a copy of the GNU Lesser General Public
19 License along with the GNU C Library; if not, see
20 <https://www.gnu.org/licenses/>. */
21
22#ifndef _HTM_H
23#define _HTM_H 1
24
25#ifdef __ASSEMBLER__
26
27/* tbegin. */
28.macro TBEGIN
29 .long 0x7c00051d
30.endm
31
32/* tend. 0 */
33.macro TEND
34 .long 0x7c00055d
35.endm
36
37/* tabort. code */
38.macro TABORT code
39 .byte 0x7c
40 .byte \code
41 .byte 0x07
42 .byte 0x1d
43.endm
44
45/*"TEXASR - Transaction EXception And Summary Register"
46 mfspr %dst,130 */
47.macro TEXASR dst
48 mfspr \dst,130
49.endm
50
51#else
52
53#include <bits/endian.h>
54
55/* Official HTM intrinsics interface matching GCC, but works
56 on older GCC compatible compilers and binutils.
57 We should somehow detect if the compiler supports it, because
58 it may be able to generate slightly better code. */
59
60#define TBEGIN ".long 0x7c00051d"
61#define TEND ".long 0x7c00055d"
62#if __BYTE_ORDER == __LITTLE_ENDIAN
63# define TABORT ".byte 0x1d,0x07,%1,0x7c"
64#else
65# define TABORT ".byte 0x7c,%1,0x07,0x1d"
66#endif
67
68#define __force_inline inline __attribute__((__always_inline__))
69
70#ifndef __HTM__
71
72#define _TEXASRU_EXTRACT_BITS(TEXASR,BITNUM,SIZE) \
73 (((TEXASR) >> (31-(BITNUM))) & ((1<<(SIZE))-1))
74#define _TEXASRU_FAILURE_PERSISTENT(TEXASRU) \
75 _TEXASRU_EXTRACT_BITS(TEXASRU, 7, 1)
76
77#define _tbegin() \
78 ({ unsigned int __ret; \
79 asm volatile ( \
80 TBEGIN "\t\n" \
81 "mfcr %0\t\n" \
82 "rlwinm %0,%0,3,1\t\n" \
83 "xori %0,%0,1\t\n" \
84 : "=r" (__ret) : \
85 : "cr0", "memory"); \
86 __ret; \
87 })
88
89#define _tend() \
90 ({ unsigned int __ret; \
91 asm volatile ( \
92 TEND "\t\n" \
93 "mfcr %0\t\n" \
94 "rlwinm %0,%0,3,1\t\n" \
95 "xori %0,%0,1\t\n" \
96 : "=r" (__ret) : \
97 : "cr0", "memory"); \
98 __ret; \
99 })
100
101#define _tabort(__code) \
102 ({ unsigned int __ret; \
103 asm volatile ( \
104 TABORT "\t\n" \
105 "mfcr %0\t\n" \
106 "rlwinm %0,%0,3,1\t\n" \
107 "xori %0,%0,1\t\n" \
108 : "=r" (__ret) : "r" (__code) \
109 : "cr0", "memory"); \
110 __ret; \
111 })
112
113#define _texasru() \
114 ({ unsigned long __ret; \
115 asm volatile ( \
116 "mfspr %0,131\t\n" \
117 : "=r" (__ret)); \
118 __ret; \
119 })
120
121#define __libc_tbegin(tdb) _tbegin ()
122#define __libc_tend(nested) _tend ()
123#define __libc_tabort(abortcode) _tabort (abortcode)
124#define __builtin_get_texasru() _texasru ()
125
126#else
127# include <htmintrin.h>
128
129# ifdef __TM_FENCE__
130 /* New GCC behavior. */
131# define __libc_tbegin(R) __builtin_tbegin (R)
132# define __libc_tend(R) __builtin_tend (R)
133# define __libc_tabort(R) __builtin_tabort (R)
134# else
135 /* Workaround an old GCC behavior. Earlier releases of GCC 4.9 and 5.0,
136 didn't use to treat __builtin_tbegin, __builtin_tend and
137 __builtin_tabort as compiler barriers, moving instructions into and
138 out the transaction.
139 Remove this when glibc drops support for GCC 5.0. */
140# define __libc_tbegin(R) \
141 ({ __asm__ volatile("" ::: "memory"); \
142 unsigned int __ret = __builtin_tbegin (R); \
143 __asm__ volatile("" ::: "memory"); \
144 __ret; \
145 })
146# define __libc_tabort(R) \
147 ({ __asm__ volatile("" ::: "memory"); \
148 unsigned int __ret = __builtin_tabort (R); \
149 __asm__ volatile("" ::: "memory"); \
150 __ret; \
151 })
152# define __libc_tend(R) \
153 ({ __asm__ volatile("" ::: "memory"); \
154 unsigned int __ret = __builtin_tend (R); \
155 __asm__ volatile("" ::: "memory"); \
156 __ret; \
157 })
158# endif /* __TM_FENCE__ */
159#endif /* __HTM__ */
160
161#endif /* __ASSEMBLER__ */
162
163/* Definitions used for TEXASR Failure code (bits 0:7). If the failure
164 should be persistent, the abort code must be odd. 0xd0 through 0xff
165 are reserved for the kernel and potential hypervisor. */
166#define _ABORT_PERSISTENT 0x01 /* An unspecified persistent abort. */
167#define _ABORT_LOCK_BUSY 0x34 /* Busy lock, not persistent. */
168#define _ABORT_NESTED_TRYLOCK (0x32 | _ABORT_PERSISTENT)
169#define _ABORT_SYSCALL (0x30 | _ABORT_PERSISTENT)
170
171#endif
172

source code of glibc/sysdeps/unix/sysv/linux/powerpc/htm.h