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+//===-- divsi3.c - Implement __divsi3 -------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __divsi3 for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "int_lib.h"
+
+su_int __udivsi3(su_int n, su_int d);
+
+// Returns: a / b
+
+si_int
+__divsi3(si_int a, si_int b)
+{
+ const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1;
+ si_int s_a = a >> bits_in_word_m1; // s_a = a < 0 ? -1 : 0
+ si_int s_b = b >> bits_in_word_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_a ^= s_b; // sign of quotient
+ return (__udivsi3(a, b) ^ s_a) - s_a; // negate if s_a == -1
+}