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-rw-r--r--lib/compiler-rt/builtins/divmoddi4.c28
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diff --git a/lib/compiler-rt/builtins/divmoddi4.c b/lib/compiler-rt/builtins/divmoddi4.c
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+//===-- 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;
+}