sysdeps/alpha/bb_init_func.S

   1 /* Copyright (C) 1996 Free Software Foundation, Inc.
   2    Contributed by David Mosberger (davidm@cs.arizona.edu).
   3
   4 This file is part of the GNU C Library.
   5
   6 The GNU C Library is free software; you can redistribute it and/or
   7 modify it under the terms of the GNU Library General Public License as
   8 published by the Free Software Foundation; either version 2 of the
   9 License, or (at your option) any later version.
  10
  11 The GNU C Library is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 Library General Public License for more details.
  15
  16 You should have received a copy of the GNU Library General Public
  17 License along with the GNU C Library; see the file COPYING.LIB.  If
  18 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  19 Cambridge, MA 02139, USA.  */
  20
  21 /* __bb_init_func is invoked at the beginning of each function, before
  22 any registers have been saved.  It is therefore safe to use any
  23 caller-saved (call-used) registers (except for argument registers
  24 a1-a5). */
  25
  26 #include <sysdep.h>
  27
  28 /*
  29  * These offsets should match with "struct bb" declared in gcc/libgcc2.c.
  30  */
  31 #define ZERO_WORD       0x00
  32 #define NEXT            0x20
  33
  34         .set    noat
  35         .set    noreorder
  36
  37 ENTRY(__bb_init_func)
  38         .prologue 0
  39
  40         ldq     t0, ZERO_WORD(a0)       /* t0 <- blocks->zero_word */
  41         beq     t0, init                /* not initialized yet -> */
  42         ret
  43
  44 END(__bb_init_func)
  45
  46         .ent init
  47 init:
  48         .frame  sp, 0x38, ra, 0
  49         subq    sp, 0x38, sp
  50         .prologue 0
  51
  52         stq     pv, 0x30(sp)
  53         br      pv, 1f
  54 1:      ldgp    gp, 0(pv)
  55
  56         ldiq    t1, __bb_head
  57         lda     t3, _gmonparam
  58         ldq     t2, 0(t1)
  59         ldl     t3, 0(t3)               /* t3 = _gmonparam.state */
  60         lda     t0, 1
  61         stq     t0, ZERO_WORD(a0)       /* blocks->zero_word = 1 */
  62         stq     t2, NEXT(a0)            /* blocks->next = __bb_head */
  63         stq     a0, 0(t1)
  64         bne     t2, $leave
  65         beq     t3, $leave              /* t3 == GMON_PROF_ON? yes -> */
  66
  67         /* also need to initialize destructor: */
  68         stq     ra, 0x00(sp)
  69         lda     a0, __bb_exit_func
  70         stq     a1, 0x08(sp)
  71         lda     pv, atexit
  72         stq     a2, 0x10(sp)
  73         stq     a3, 0x18(sp)
  74         stq     a4, 0x20(sp)
  75         stq     a5, 0x28(sp)
  76         jsr     ra, (pv), atexit
  77         ldq     ra, 0x00(sp)
  78         ldq     a1, 0x08(sp)
  79         ldq     a2, 0x10(sp)
  80         ldq     a3, 0x18(sp)
  81         ldq     a4, 0x20(sp)
  82         ldq     a5, 0x28(sp)
  83
  84 $leave: ldq     pv, 0x30(sp)
  85         addq    sp, 0x38, sp
  86         ret
  87
  88         .end init