sys/external/bsd/compiler_rt/dist/lib/builtins/i386/floatdidf.S

   1 // This file is dual licensed under the MIT and the University of Illinois Open
   2 // Source Licenses. See LICENSE.TXT for details.
   3
   4 #include "../assembly.h"
   5
   6 // double __floatundidf(du_int a);
   7
   8 #ifdef __i386__
   9
  10 #if defined(__APPLE__)
  11         .const
  12 #elif defined(__ELF__)
  13         .section .rodata
  14 #else
  15         .section .rdata,"rd"
  16 #endif
  17
  18         .balign 16
  19 twop52:
  20         .quad 0x4330000000000000
  21
  22         .balign 16
  23 twop32:
  24         .quad 0x41f0000000000000
  25
  26 #define REL_ADDR(_a)    (_a)-0b(%eax)
  27
  28 .text
  29 .balign 4
  30 DEFINE_COMPILERRT_FUNCTION(__floatdidf)
  31         cvtsi2sd        8(%esp),                        %xmm1
  32         movss           4(%esp),                        %xmm0 // low 32 bits of a
  33         calll           0f
  34 0:      popl            %eax
  35         mulsd           REL_ADDR(twop32),       %xmm1 // a_hi as a double (without rounding)
  36         movsd           REL_ADDR(twop52),       %xmm2 // 0x1.0p52
  37         subsd           %xmm2,                          %xmm1 // a_hi - 0x1p52 (no rounding occurs)
  38         orpd            %xmm2,                          %xmm0 // 0x1p52 + a_lo (no rounding occurs)
  39         addsd           %xmm1,                          %xmm0 // a_hi + a_lo   (round happens here)
  40         movsd           %xmm0,                     4(%esp)
  41         fldl       4(%esp)
  42         ret
  43 END_COMPILERRT_FUNCTION(__floatdidf)
  44
  45 #endif // __i386__