1//===-- floatundidf.S - Implement __floatundidf for x86_64 ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements __floatundidf for the compiler_rt library.
11//
12//===----------------------------------------------------------------------===//
13
14#include "../assembly.h"
15
16// double __floatundidf(du_int a);
17
18#ifdef __x86_64__
19
20#if defined(__APPLE__)
21	.const
22#elif defined(__ELF__)
23	.section .rodata
24#else
25	.section .rdata,"rd"
26#endif
27
28	.balign 16
29twop52:
30	.quad 0x4330000000000000
31
32	.balign 16
33twop84_plus_twop52:
34	.quad 0x4530000000100000
35
36	.balign 16
37twop84:
38	.quad 0x4530000000000000
39
40#define REL_ADDR(_a)	(_a)(%rip)
41
42.text
43.balign 4
44DEFINE_COMPILERRT_FUNCTION(__floatundidf)
45	movd	%edi,							%xmm0 // low 32 bits of a
46	shrq	$32,							%rdi  // high 32 bits of a
47	orq		REL_ADDR(twop84),				%rdi  // 0x1p84 + a_hi (no rounding occurs)
48	orpd	REL_ADDR(twop52),				%xmm0 // 0x1p52 + a_lo (no rounding occurs)
49	movd	%rdi,							%xmm1
50	subsd	REL_ADDR(twop84_plus_twop52),	%xmm1 // a_hi - 0x1p52 (no rounding occurs)
51	addsd	%xmm1,							%xmm0 // a_hi + a_lo   (round happens here)
52	ret
53END_COMPILERRT_FUNCTION(__floatundidf)
54
55#endif // __x86_64__
56