1  /* Assembler macros for 64 bit S/390.
       2     Copyright (C) 2001-2023 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__ */