xref: /external/libffi/src/powerpc/asm.h

/* -----------------------------------------------------------------------
   asm.h - Copyright (c) 1998 Geoffrey Keating

   PowerPC Assembly glue.

   Permission is hereby granted, free of charge, to any person obtaining
   a copy of this software and associated documentation files (the
   ``Software''), to deal in the Software without restriction, including
   without limitation the rights to use, copy, modify, merge, publish,
   distribute, sublicense, and/or sell copies of the Software, and to
   permit persons to whom the Software is furnished to do so, subject to
   the following conditions:

   The above copyright notice and this permission notice shall be included
   in all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
   IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR
   OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
   ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   OTHER DEALINGS IN THE SOFTWARE.
   ----------------------------------------------------------------------- */

#define ASM_GLOBAL_DIRECTIVE .globl


#define C_SYMBOL_NAME(name) name
/* Macro for a label.  */
#ifdef	__STDC__
#define C_LABEL(name)		name##:
#else
#define C_LABEL(name)		name/**/:
#endif

/* This seems to always be the case on PPC.  */
#define ALIGNARG(log2) log2
/* For ELF we need the `.type' directive to make shared libs work right.  */
#define ASM_TYPE_DIRECTIVE(name,typearg) .type name,typearg;
#define ASM_SIZE_DIRECTIVE(name) .size name,.-name

/* If compiled for profiling, call `_mcount' at the start of each function.  */
#ifdef	PROF
/* The mcount code relies on a the return address being on the stack
   to locate our caller and so it can restore it; so store one just
   for its benefit.  */
#ifdef PIC
#define CALL_MCOUNT							      \
  .pushsection;								      \
  .section ".data";							      \
  .align ALIGNARG(2);							      \
0:.long 0;								      \
  .previous;								      \
  mflr  %r0;								      \
  stw   %r0,4(%r1);							      \
  bl    _GLOBAL_OFFSET_TABLE_@local-4;					      \
  mflr  %r11;								      \
  lwz   %r0,0b@got(%r11);						      \
  bl    JUMPTARGET(_mcount);
#else  /* PIC */
#define CALL_MCOUNT							      \
  .section ".data";							      \
  .align ALIGNARG(2);							      \
0:.long 0;								      \
  .previous;								      \
  mflr  %r0;								      \
  lis   %r11,0b@ha;							      \
  stw   %r0,4(%r1);							      \
  addi  %r0,%r11,0b@l;							      \
  bl    JUMPTARGET(_mcount);
#endif /* PIC */
#else  /* PROF */
#define CALL_MCOUNT		/* Do nothing.  */
#endif /* PROF */

#define	ENTRY(name)							      \
  ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)			      \
  .align ALIGNARG(2);							      \
  C_LABEL(name)								      \
  CALL_MCOUNT

#define EALIGN_W_0  /* No words to insert.  */
#define EALIGN_W_1  nop
#define EALIGN_W_2  nop;nop
#define EALIGN_W_3  nop;nop;nop
#define EALIGN_W_4  EALIGN_W_3;nop
#define EALIGN_W_5  EALIGN_W_4;nop
#define EALIGN_W_6  EALIGN_W_5;nop
#define EALIGN_W_7  EALIGN_W_6;nop

/* EALIGN is like ENTRY, but does alignment to 'words'*4 bytes
   past a 2^align boundary.  */
#ifdef PROF
#define EALIGN(name, alignt, words)					      \
  ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)			      \
  .align ALIGNARG(2);							      \
  C_LABEL(name)								      \
  CALL_MCOUNT								      \
  b 0f;									      \
  .align ALIGNARG(alignt);						      \
  EALIGN_W_##words;							      \
  0:
#else /* PROF */
#define EALIGN(name, alignt, words)					      \
  ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function)			      \
  .align ALIGNARG(alignt);						      \
  EALIGN_W_##words;							      \
  C_LABEL(name)
#endif

#define END(name)							      \
  ASM_SIZE_DIRECTIVE(name)

#ifdef PIC
#define JUMPTARGET(name) name##@plt
#else
#define JUMPTARGET(name) name
#endif

/* Local labels stripped out by the linker.  */
#define L(x) .L##x