arm-trusted-firmware/lib/compiler-rt/builtins/divmoddi4.c
Daniel Boulby 8a6a9560b5 feat(compiler-rt): update compiler-rt source files
Update the compiler-rt source files to the tip of the llvm-project [1].
To do this some new header files were pulled in from the freebsd-src
repo [2].

[1] https://github.com/llvm/llvm-project/commit/fae258e
[2] https://github.com/freebsd/freebsd-src/commit/243a0eda

Change-Id: I1a012b1fe04e127d35e208923877c98c5d999d00
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
2022-10-24 16:49:32 +01:00

28 lines
1.3 KiB
C

//===-- divmoddi4.c - Implement __divmoddi4 -------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements __divmoddi4 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "int_lib.h"
// Returns: a / b, *rem = a % b
COMPILER_RT_ABI di_int __divmoddi4(di_int a, di_int b, di_int *rem) {
const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1;
di_int s_a = a >> bits_in_dword_m1; // s_a = a < 0 ? -1 : 0
di_int s_b = b >> bits_in_dword_m1; // s_b = b < 0 ? -1 : 0
a = (a ^ s_a) - s_a; // negate if s_a == -1
b = (b ^ s_b) - s_b; // negate if s_b == -1
s_b ^= s_a; // sign of quotient
du_int r;
di_int q = (__udivmoddi4(a, b, &r) ^ s_b) - s_b; // negate if s_b == -1
*rem = (r ^ s_a) - s_a; // negate if s_a == -1
return q;
}