diff options
Diffstat (limited to 'lib/i386/floatdidf.s')
| -rw-r--r-- | lib/i386/floatdidf.s | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/lib/i386/floatdidf.s b/lib/i386/floatdidf.s new file mode 100644 index 000000000..34736ac58 --- /dev/null +++ b/lib/i386/floatdidf.s @@ -0,0 +1,32 @@ +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. + +// double __floatundidf(du_int a); + +#ifdef __i386__ + +.const +.align 4 +twop52: .quad 0x4330000000000000 +twop32: .quad 0x41f0000000000000 + +#define REL_ADDR(_a) (_a)-0b(%eax) + +.text +.align 4 +.globl ___floatdidf +___floatdidf: + cvtsi2sd 8(%esp), %xmm1 + movss 4(%esp), %xmm0 // low 32 bits of a + calll 0f +0: popl %eax + mulsd REL_ADDR(twop32), %xmm1 // a_hi as a double (without rounding) + movsd REL_ADDR(twop52), %xmm2 // 0x1.0p52 + subsd %xmm2, %xmm1 // a_hi - 0x1p52 (no rounding occurs) + orpd %xmm2, %xmm0 // 0x1p52 + a_lo (no rounding occurs) + addsd %xmm1, %xmm0 // a_hi + a_lo (round happens here) + movsd %xmm0, 4(%esp) + fldl 4(%esp) + ret + +#endif // __i386__ |