xref: /freebsd/contrib/llvm-project/compiler-rt/lib/builtins/arm/truncdfsf2vfp.S (revision 349cc55c9796c4596a5b9904cd3281af295f878f)
1//===-- truncdfsf2vfp.S - Implement truncdfsf2vfp -------------------------===//
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-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "../assembly.h"
10
11//
12// extern float __truncdfsf2vfp(double a);
13//
14// Converts double precision float to single precision result.
15// Uses Darwin calling convention where a double precision parameter is
16// passed in a R0/R1 pair and a single precision result is returned in R0.
17//
18	.syntax unified
19	.p2align 2
20DEFINE_COMPILERRT_FUNCTION(__truncdfsf2vfp)
21#if defined(COMPILER_RT_ARMHF_TARGET)
22	vcvt.f32.f64 s0, d0
23#else
24	vmov 	d7, r0, r1   // load double from r0/r1 pair
25	vcvt.f32.f64 s15, d7 // convert double to single (trucate precision)
26	vmov 	r0, s15      // return result in r0
27#endif
28	bx	lr
29END_COMPILERRT_FUNCTION(__truncdfsf2vfp)
30
31NO_EXEC_STACK_DIRECTIVE
32
33