1//===-- extendsfdf2vfp.S - Implement extendsfdf2vfp -----------------------===//
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 double __extendsfdf2vfp(float a);
13//
14// Converts single precision float to double precision result.
15// Uses Darwin calling convention where a single precision parameter is
16// passed in a GPR and a double precision result is returned in R0/R1 pair.
17//
18 .syntax unified
19 .p2align 2
20DEFINE_COMPILERRT_FUNCTION(__extendsfdf2vfp)
21#if defined(COMPILER_RT_ARMHF_TARGET)
22 vcvt.f64.f32 d0, s0
23#else
24 vmov s15, r0 // load float register from R0
25 vcvt.f64.f32 d7, s15 // convert single to double
26 vmov r0, r1, d7 // return result in r0/r1 pair
27#endif
28 bx lr
29END_COMPILERRT_FUNCTION(__extendsfdf2vfp)
30
31NO_EXEC_STACK_DIRECTIVE
32
33

source code of compiler-rt/lib/builtins/arm/extendsfdf2vfp.S