1 /* Assembler macros for 64 bit S/390.
2    Copyright (C) 2001-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <sysdeps/generic/sysdep.h>
20 
21 #ifdef	__ASSEMBLER__
22 
23 /* Syntactic details of assembler.  */
24 
25 /* ELF uses byte-counts for .align, most others use log2 of count of bytes.  */
26 #define ALIGNARG(log2) 1<<log2
27 #define ASM_SIZE_DIRECTIVE(name) .size name,.-name;
28 
29 
30 /* Define an entry point visible from C. */
31 #define	ENTRY(name)							      \
32   .globl C_SYMBOL_NAME(name);						      \
33   .type C_SYMBOL_NAME(name),@function;					      \
34   .align ALIGNARG(4);							      \
35   C_LABEL(name)								      \
36   cfi_startproc;							      \
37   CALL_MCOUNT
38 
39 #undef	END
40 #define END(name)							      \
41   cfi_endproc;								      \
42   ASM_SIZE_DIRECTIVE(name)						      \
43 
44 /* If compiled for profiling, call `mcount' at the start of each function.  */
45 #ifdef	PROF
46 #ifdef PIC
47 #define CALL_MCOUNT \
48   lgr 0,14 ; larl 1,0f ; brasl 14,_mcount@PLT ; lgr 14,0 ; \
49   .data ; .align 4 ; 0: .long 0 ; .text ;
50 #else
51 #define CALL_MCOUNT \
52   lgr 0,14 ; larl 1,0f ; brasl 14,_mcount ; lgr 14,0 ; \
53   .data ; .align 4 ; 0: .long 0 ; .text ;
54 #endif
55 #else
56 #define CALL_MCOUNT		/* Do nothing.  */
57 #endif
58 
59 /* Since C identifiers are not normally prefixed with an underscore
60    on this system, the asm identifier `syscall_error' intrudes on the
61    C name space.  Make sure we use an innocuous name.  */
62 #define	syscall_error	__syscall_error
63 #define mcount		_mcount
64 
65 #undef PSEUDO
66 #define	PSEUDO(name, syscall_name, args) \
67 lose: SYSCALL_PIC_SETUP			\
68   jg JUMPTARGET(syscall_error);		\
69   .globl syscall_error;			\
70   ENTRY (name)				\
71   DO_CALL (syscall_name, args);		\
72   jm lose
73 
74 #undef	PSEUDO_END
75 #define	PSEUDO_END(name)						      \
76   END (name)
77 
78 #undef JUMPTARGET
79 #ifdef SHARED
80 #define JUMPTARGET(name)	name##@PLT
81 #define SYSCALL_PIC_SETUP \
82     larl  %r12,_GLOBAL_OFFSET_TABLE_
83 #else
84 #define JUMPTARGET(name)	name
85 #define SYSCALL_PIC_SETUP	/* Nothing.  */
86 #endif
87 
88 /* Local label name for asm code. */
89 #ifndef L
90 #define L(name)		.L##name
91 #endif
92 
93 #endif	/* __ASSEMBLER__ */
94