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1//===-- floatundidf.S - Implement __floatundidf for x86_64 ----------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements __floatundidf for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "../assembly.h"14 15// double __floatundidf(du_int a);16 17#ifdef __x86_64__18 19CONST_SECTION20 21 .balign 1622twop52:23 .quad 0x433000000000000024 25 .balign 1626twop84_plus_twop52:27 .quad 0x453000000010000028 29 .balign 1630twop84:31 .quad 0x453000000000000032 33#define REL_ADDR(_a) (_a)(%rip)34 35.text36.balign 437DEFINE_COMPILERRT_FUNCTION(__floatundidf)38 movd %edi, %xmm0 // low 32 bits of a39 shrq $32, %rdi // high 32 bits of a40 orq REL_ADDR(twop84), %rdi // 0x1p84 + a_hi (no rounding occurs)41 orpd REL_ADDR(twop52), %xmm0 // 0x1p52 + a_lo (no rounding occurs)42 movd %rdi, %xmm143 subsd REL_ADDR(twop84_plus_twop52), %xmm1 // a_hi - 0x1p52 (no rounding occurs)44 addsd %xmm1, %xmm0 // a_hi + a_lo (round happens here)45 ret46END_COMPILERRT_FUNCTION(__floatundidf)47 48#endif // __x86_64__49 50NO_EXEC_STACK_DIRECTIVE51 52