sysdeps/alpha/reml.S

   1 /* Copyright (C) 2004 Free Software Foundation, Inc.
   2    Contributed by Richard Henderson  <rth@twiddle.net>
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include "div_libc.h"
  21
  22 /* 32-bit signed int remainder.  This is not a normal C function.  Argument
  23    registers are t10 and t11, the result goes in t12.  Only t12 and AT may
  24    be clobbered.
  25
  26    The FPU can handle the division for all input values except zero.
  27    All we have to do is compute the remainder via multiply-and-subtract.
  28
  29    The FPCR save/restore is due to the fact that the EV6 _will_ set FPCR_INE
  30    for cvttq/c even without /sui being set.  It will not, however, properly
  31    raise the exception, so we don't have to worry about FPCR_INED being clear
  32    and so dying by SIGFPE.  */
  33
  34 #ifndef EXTEND
  35 #define EXTEND(S,D)     sextl S, D
  36 #endif
  37
  38         .text
  39         .align  4
  40         .globl  __reml
  41         .type   __reml, @funcnoplt
  42         .usepv  __reml, no
  43
  44         cfi_startproc
  45         cfi_return_column (RA)
  46 __reml:
  47         lda     sp, -FRAME(sp)
  48         cfi_def_cfa_offset (FRAME)
  49         CALL_MCOUNT
  50         stt     $f0, 0(sp)
  51         excb
  52         beq     Y, DIVBYZERO
  53
  54         stt     $f1, 8(sp)
  55         stt     $f2, 16(sp)
  56         cfi_rel_offset ($f0, 0)
  57         cfi_rel_offset ($f1, 8)
  58         cfi_rel_offset ($f2, 16)
  59         mf_fpcr $f2
  60
  61         EXTEND  (X, RV)
  62         EXTEND  (Y, AT)
  63         _ITOFT2 RV, $f0, 24, AT, $f1, 32
  64         cvtqt   $f0, $f0
  65         cvtqt   $f1, $f1
  66         divt/c  $f0, $f1, $f0
  67         cvttq/c $f0, $f0
  68         excb
  69         mt_fpcr $f2
  70         _FTOIT  $f0, RV, 24
  71
  72         ldt     $f0, 0(sp)
  73         mull    RV, Y, RV
  74         ldt     $f1, 8(sp)
  75         ldt     $f2, 16(sp)
  76         lda     sp, FRAME(sp)
  77         cfi_restore ($f0)
  78         cfi_restore ($f1)
  79         cfi_restore ($f2)
  80         cfi_def_cfa_offset (0)
  81         subl    X, RV, RV
  82         ret     $31, (RA), 1
  83
  84         cfi_endproc
  85         .size   __reml, .-__reml
  86
  87         DO_DIVBYZERO