1  /* Assembler macros for s390.
       2     Copyright (C) 2000-2023 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    lr 0,14 ; bras 14,.+12 ; .long _GLOBAL_OFFSET_TABLE_ - . ; .long 0f-. ; \
      49    lr 1,14 ; al 1,4(14) ; al 14,0(14) ; l 14,_mcount@GOT(14) ; \
      50    basr 14,14 ; lr 14,0 ; .data ; .align 4 ; 0: .long 0 ; .text ;
      51  #else
      52  #define CALL_MCOUNT \
      53    lr 0,14 ; bras 14,.+12 ; .long _mcount ; .long 0f ; \
      54    l 1,4(14) ; l 14,0(14) ; basr 14,14 ; lr 14,0 ; \
      55    .data ; .align 4 ; 0: .long 0 ; .text ;
      56  #endif
      57  #else
      58  #define CALL_MCOUNT		/* Do nothing.  */
      59  #endif
      60  
      61  /* Since C identifiers are not normally prefixed with an underscore
      62     on this system, the asm identifier `syscall_error' intrudes on the
      63     C name space.  Make sure we use an innocuous name.  */
      64  #define	syscall_error	__syscall_error
      65  #define mcount		_mcount
      66  
      67  #undef PSEUDO
      68  #define	PSEUDO(name, syscall_name, args) \
      69  lose: SYSCALL_PIC_SETUP				\
      70      basr %r1,0;					\
      71  0:  al %r1,1f-0b(%r1);				\
      72      br %r1;					\
      73  1:  .long JUMPTARGET(syscall_error) - 0b;	\
      74      .globl syscall_error;			\
      75      ENTRY (name)				\
      76      DO_CALL (syscall_name, args);		\
      77      jm lose
      78  
      79  #undef	PSEUDO_END
      80  #define	PSEUDO_END(name)						      \
      81    END (name)
      82  
      83  #undef JUMPTARGET
      84  #ifdef SHARED
      85  #define JUMPTARGET(name)	name##@PLT
      86  #define SYSCALL_PIC_SETUP             \
      87      bras  %r12,1f;		      \
      88  0:  .long _GLOBAL_OFFSET_TABLE_-0b;   \
      89  1:  al    %r12,0(%r12)
      90  #else
      91  #define JUMPTARGET(name)	name
      92  #define SYSCALL_PIC_SETUP	/* Nothing.  */
      93  #endif
      94  
      95  /* Local label name for asm code. */
      96  #ifndef L
      97  #define L(name)		.L##name
      98  #endif
      99  
     100  #endif	/* __ASSEMBLER__ */