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
19twop52:
20	.quad 0x4330000000000000
21
22	.balign 16
23twop32:
24	.quad 0x41f0000000000000
25
26#define REL_ADDR(_a)	(_a)-0b(%eax)
27
28.text
29.balign 4
30DEFINE_COMPILERRT_FUNCTION(__floatdidf)
31	cvtsi2sd	8(%esp),			%xmm1
32	movss		4(%esp),			%xmm0 // low 32 bits of a
33	calll		0f
340:	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
43END_COMPILERRT_FUNCTION(__floatdidf)
44
45#endif // __i386__
46