Home | History | Annotate | Line # | Download | only in i386
floatdidf.S revision 1.1.1.3.4.2 
      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__
     46