diff options
Diffstat (limited to 'lib/builtins/mulvdi3.c')
-rw-r--r-- | lib/builtins/mulvdi3.c | 89 |
1 files changed, 40 insertions, 49 deletions
diff --git a/lib/builtins/mulvdi3.c b/lib/builtins/mulvdi3.c index e63249e0a04c..cecc97ccf22e 100644 --- a/lib/builtins/mulvdi3.c +++ b/lib/builtins/mulvdi3.c @@ -1,56 +1,47 @@ -/*===-- mulvdi3.c - Implement __mulvdi3 -----------------------------------=== - * - * The LLVM Compiler Infrastructure - * - * This file is dual licensed under the MIT and the University of Illinois Open - * Source Licenses. See LICENSE.TXT for details. - * - * ===----------------------------------------------------------------------=== - * - * This file implements __mulvdi3 for the compiler_rt library. - * - * ===----------------------------------------------------------------------=== - */ +//===-- mulvdi3.c - Implement __mulvdi3 -----------------------------------===// +// +// 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 __mulvdi3 for the compiler_rt library. +// +//===----------------------------------------------------------------------===// #include "int_lib.h" -/* Returns: a * b */ +// Returns: a * b -/* Effects: aborts if a * b overflows */ +// Effects: aborts if a * b overflows -COMPILER_RT_ABI di_int -__mulvdi3(di_int a, di_int b) -{ - const int N = (int)(sizeof(di_int) * CHAR_BIT); - const di_int MIN = (di_int)1 << (N-1); - const di_int MAX = ~MIN; - if (a == MIN) - { - if (b == 0 || b == 1) - return a * b; - compilerrt_abort(); - } - if (b == MIN) - { - if (a == 0 || a == 1) - return a * b; - compilerrt_abort(); - } - di_int sa = a >> (N - 1); - di_int abs_a = (a ^ sa) - sa; - di_int sb = b >> (N - 1); - di_int abs_b = (b ^ sb) - sb; - if (abs_a < 2 || abs_b < 2) - return a * b; - if (sa == sb) - { - if (abs_a > MAX / abs_b) - compilerrt_abort(); - } - else - { - if (abs_a > MIN / -abs_b) - compilerrt_abort(); - } +COMPILER_RT_ABI di_int __mulvdi3(di_int a, di_int b) { + const int N = (int)(sizeof(di_int) * CHAR_BIT); + const di_int MIN = (di_int)1 << (N - 1); + const di_int MAX = ~MIN; + if (a == MIN) { + if (b == 0 || b == 1) + return a * b; + compilerrt_abort(); + } + if (b == MIN) { + if (a == 0 || a == 1) + return a * b; + compilerrt_abort(); + } + di_int sa = a >> (N - 1); + di_int abs_a = (a ^ sa) - sa; + di_int sb = b >> (N - 1); + di_int abs_b = (b ^ sb) - sb; + if (abs_a < 2 || abs_b < 2) return a * b; + if (sa == sb) { + if (abs_a > MAX / abs_b) + compilerrt_abort(); + } else { + if (abs_a > MIN / -abs_b) + compilerrt_abort(); + } + return a * b; } |