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diff --git a/lib/compiler-rt/builtins/int_div_impl.inc b/lib/compiler-rt/builtins/int_div_impl.inc
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+//===-- int_div_impl.inc - Integer division ---------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Helpers used by __udivsi3, __umodsi3, __udivdi3, and __umodsi3.
+//
+//===----------------------------------------------------------------------===//
+
+#define clz(a) (sizeof(a) == sizeof(unsigned long long) ? __builtin_clzll(a) : clzsi(a))
+
+// Adapted from Figure 3-40 of The PowerPC Compiler Writer's Guide
+static __inline fixuint_t __udivXi3(fixuint_t n, fixuint_t d) {
+ const unsigned N = sizeof(fixuint_t) * CHAR_BIT;
+ // d == 0 cases are unspecified.
+ unsigned sr = (d ? clz(d) : N) - (n ? clz(n) : N);
+ // 0 <= sr <= N - 1 or sr is very large.
+ if (sr > N - 1) // n < d
+ return 0;
+ if (sr == N - 1) // d == 1
+ return n;
+ ++sr;
+ // 1 <= sr <= N - 1. Shifts do not trigger UB.
+ fixuint_t r = n >> sr;
+ n <<= N - sr;
+ fixuint_t carry = 0;
+ for (; sr > 0; --sr) {
+ r = (r << 1) | (n >> (N - 1));
+ n = (n << 1) | carry;
+ // Branch-less version of:
+ // carry = 0;
+ // if (r >= d) r -= d, carry = 1;
+ const fixint_t s = (fixint_t)(d - r - 1) >> (N - 1);
+ carry = s & 1;
+ r -= d & s;
+ }
+ n = (n << 1) | carry;
+ return n;
+}
+
+// Mostly identical to __udivXi3 but the return values are different.
+static __inline fixuint_t __umodXi3(fixuint_t n, fixuint_t d) {
+ const unsigned N = sizeof(fixuint_t) * CHAR_BIT;
+ // d == 0 cases are unspecified.
+ unsigned sr = (d ? clz(d) : N) - (n ? clz(n) : N);
+ // 0 <= sr <= N - 1 or sr is very large.
+ if (sr > N - 1) // n < d
+ return n;
+ if (sr == N - 1) // d == 1
+ return 0;
+ ++sr;
+ // 1 <= sr <= N - 1. Shifts do not trigger UB.
+ fixuint_t r = n >> sr;
+ n <<= N - sr;
+ fixuint_t carry = 0;
+ for (; sr > 0; --sr) {
+ r = (r << 1) | (n >> (N - 1));
+ n = (n << 1) | carry;
+ // Branch-less version of:
+ // carry = 0;
+ // if (r >= d) r -= d, carry = 1;
+ const fixint_t s = (fixint_t)(d - r - 1) >> (N - 1);
+ carry = s & 1;
+ r -= d & s;
+ }
+ return r;
+}
+
+#ifdef COMPUTE_UDIV
+static __inline fixint_t __divXi3(fixint_t a, fixint_t b) {
+ const int N = (int)(sizeof(fixint_t) * CHAR_BIT) - 1;
+ fixint_t s_a = a >> N; // s_a = a < 0 ? -1 : 0
+ fixint_t s_b = b >> N; // s_b = b < 0 ? -1 : 0
+ fixuint_t a_u = (fixuint_t)(a ^ s_a) + (-s_a); // negate if s_a == -1
+ fixuint_t b_u = (fixuint_t)(b ^ s_b) + (-s_b); // negate if s_b == -1
+ s_a ^= s_b; // sign of quotient
+ return (COMPUTE_UDIV(a_u, b_u) ^ s_a) + (-s_a); // negate if s_a == -1
+}
+#endif // COMPUTE_UDIV
+
+#ifdef ASSIGN_UMOD
+static __inline fixint_t __modXi3(fixint_t a, fixint_t b) {
+ const int N = (int)(sizeof(fixint_t) * CHAR_BIT) - 1;
+ fixint_t s = b >> N; // s = b < 0 ? -1 : 0
+ fixuint_t b_u = (fixuint_t)(b ^ s) + (-s); // negate if s == -1
+ s = a >> N; // s = a < 0 ? -1 : 0
+ fixuint_t a_u = (fixuint_t)(a ^ s) + (-s); // negate if s == -1
+ fixuint_t res;
+ ASSIGN_UMOD(res, a_u, b_u);
+ return (res ^ s) + (-s); // negate if s == -1
+}
+#endif // ASSIGN_UMOD