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