llvm-project/compiler-rt/lib/x86_64/floatundidf.S

40 lines
1.2 KiB
ArmAsm

//===-- floatundidf.s - Implement __floatundidf for x86_64 ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __floatundidf for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
// double __floatundidf(du_int a);
#ifdef __x86_64__
.const
.align 4
twop52: .quad 0x4330000000000000
twop84_plus_twop52:
.quad 0x4530000000100000
twop84: .quad 0x4530000000000000
#define REL_ADDR(_a) (_a)(%rip)
.text
.align 4
.globl ___floatundidf
___floatundidf:
movd %edi, %xmm0 // low 32 bits of a
shrq $32, %rdi // high 32 bits of a
orq REL_ADDR(twop84), %rdi // 0x1p84 + a_hi (no rounding occurs)
orpd REL_ADDR(twop52), %xmm0 // 0x1p52 + a_lo (no rounding occurs)
movd %rdi, %xmm1
subsd REL_ADDR(twop84_plus_twop52), %xmm1 // a_hi - 0x1p52 (no rounding occurs)
addsd %xmm1, %xmm0 // a_hi + a_lo (round happens here)
ret
#endif // __x86_64__