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+/** @file
+ Compiler intrinsic for 32-bit unsigned div, ported from LLVM code.
+
+ Copyright (c) 2008-2009, Apple Inc. All rights reserved.
+
+ All rights reserved. This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+/**
+ University of Illinois/NCSA
+ Open Source License
+
+ Copyright (c) 2003-2008 University of Illinois at Urbana-Champaign.
+ All rights reserved.
+
+ Developed by:
+
+ LLVM Team
+
+ University of Illinois at Urbana-Champaign
+
+ http://llvm.org
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy of
+ this software and associated documentation files (the "Software"), to deal with
+ the Software without restriction, including without limitation the rights to
+ use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+ of the Software, and to permit persons to whom the Software is furnished to do
+ so, subject to the following conditions:
+
+ * Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimers.
+
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimers in the
+ documentation and/or other materials provided with the distribution.
+
+ * Neither the names of the LLVM Team, University of Illinois at
+ Urbana-Champaign, nor the names of its contributors may be used to
+ endorse or promote products derived from this Software without specific
+ prior written permission.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
+ SOFTWARE.
+**/
+
+
+#include "Llvm_int_lib.h"
+
+
+// Returns: n / d
+
+// Translated from Figure 3-40 of The PowerPC Compiler Writer's Guide
+
+UINT32
+__udivsi3(UINT32 n, UINT32 d)
+{
+ const unsigned n_uword_bits = sizeof(UINT32) * CHAR_BIT;
+ UINT32 q;
+ UINT32 r;
+ unsigned sr;
+
+ // special cases
+ if (d == 0) {
+// ASSERT (FALSE);
+ return 0; // ?!
+ }
+ if (n == 0)
+ return 0;
+
+ sr = COUNT_LEADING_ZEROS(d) - COUNT_LEADING_ZEROS(n);
+ // 0 <= sr <= n_uword_bits - 1 or sr large
+ if (sr > n_uword_bits - 1) // d > r
+ return 0;
+ if (sr == n_uword_bits - 1) // d == 1
+ return n;
+ ++sr;
+ // 1 <= sr <= n_uword_bits - 1
+ // Not a special case
+ q = n << (n_uword_bits - sr);
+ r = n >> sr;
+ UINT32 carry = 0;
+ for (; sr > 0; --sr)
+ {
+ // r:q = ((r:q) << 1) | carry
+ r = (r << 1) | (q >> (n_uword_bits - 1));
+ q = (q << 1) | carry;
+ // carry = 0;
+ // if (r.all >= d.all)
+ // {
+ // r.all -= d.all;
+ // carry = 1;
+ // }
+ const INT32 s = (INT32)(d - r - 1) >> (n_uword_bits - 1);
+ carry = s & 1;
+ r -= d & s;
+ }
+ q = (q << 1) | carry;
+ return q;
+}