xref: /freebsd/contrib/llvm-project/compiler-rt/lib/builtins/i386/floatdixf.S (revision 5f757f3ff9144b609b3c433dfd370cc6bdc191ad)
10b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
20b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information.
30b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
40b57cec5SDimitry Andric
50b57cec5SDimitry Andric#include "../assembly.h"
60b57cec5SDimitry Andric
7*5f757f3fSDimitry Andric// xf_float __floatdixf(di_int a);
80b57cec5SDimitry Andric
90b57cec5SDimitry Andric#ifdef __i386__
100b57cec5SDimitry Andric
110b57cec5SDimitry Andric// This routine has some extra memory traffic, loading the 64-bit input via two
120b57cec5SDimitry Andric// 32-bit loads, then immediately storing it back to the stack via a single 64-bit
130b57cec5SDimitry Andric// store.  This is to avoid a write-small, read-large stall.
140b57cec5SDimitry Andric// However, if callers of this routine can be safely assumed to store the argument
150b57cec5SDimitry Andric// via a 64-bt store, this is unnecessary memory traffic, and should be avoided.
160b57cec5SDimitry Andric// It can be turned off by defining the TRUST_CALLERS_USE_64_BIT_STORES macro.
170b57cec5SDimitry Andric
180b57cec5SDimitry Andric.text
190b57cec5SDimitry Andric.balign 4
200b57cec5SDimitry AndricDEFINE_COMPILERRT_FUNCTION(__floatdixf)
210b57cec5SDimitry Andric#ifndef TRUST_CALLERS_USE_64_BIT_STORES
220b57cec5SDimitry Andric	movd		4(%esp),	%xmm0
230b57cec5SDimitry Andric	movd		8(%esp),	%xmm1
240b57cec5SDimitry Andric	punpckldq	%xmm1,		%xmm0
250b57cec5SDimitry Andric	movq		%xmm0,		4(%esp)
260b57cec5SDimitry Andric#endif
270b57cec5SDimitry Andric	fildll		4(%esp)
280b57cec5SDimitry Andric	ret
290b57cec5SDimitry AndricEND_COMPILERRT_FUNCTION(__floatdixf)
300b57cec5SDimitry Andric
310b57cec5SDimitry Andric#endif // __i386__
320b57cec5SDimitry Andric
330b57cec5SDimitry AndricNO_EXEC_STACK_DIRECTIVE
340b57cec5SDimitry Andric
35