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<div class="headertitle"><div class="title">saturated_arithmetic.h</div></div>
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<a href="saturated__arithmetic_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno"> 1</span><span class="comment">// Copyright 2010-2021 Google LLC</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno"> 2</span><span class="comment">// Licensed under the Apache License, Version 2.0 (the &quot;License&quot;);</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno"> 3</span><span class="comment">// you may not use this file except in compliance with the License.</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno"> 4</span><span class="comment">// You may obtain a copy of the License at</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno"> 5</span><span class="comment">//</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno"> 6</span><span class="comment">// http://www.apache.org/licenses/LICENSE-2.0</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno"> 7</span><span class="comment">//</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno"> 8</span><span class="comment">// Unless required by applicable law or agreed to in writing, software</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno"> 9</span><span class="comment">// distributed under the License is distributed on an &quot;AS IS&quot; BASIS,</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno"> 10</span><span class="comment">// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno"> 11</span><span class="comment">// See the License for the specific language governing permissions and</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno"> 12</span><span class="comment">// limitations under the License.</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno"> 13</span> </div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno"> 14</span><span class="preprocessor">#ifndef OR_TOOLS_UTIL_SATURATED_ARITHMETIC_H_</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno"> 15</span><span class="preprocessor">#define OR_TOOLS_UTIL_SATURATED_ARITHMETIC_H_</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno"> 16</span> </div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno"> 17</span><span class="preprocessor">#include &quot;absl/base/casts.h&quot;</span></div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno"> 18</span><span class="preprocessor">#include &quot;<a class="code" href="integral__types_8h.html">ortools/base/integral_types.h</a>&quot;</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno"> 19</span><span class="preprocessor">#include &quot;<a class="code" href="bitset_8h.html">ortools/util/bitset.h</a>&quot;</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno"> 20</span> </div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno"> 21</span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceoperations__research.html">operations_research</a> {</div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno"> 22</span><span class="comment">// ---------- Overflow utility functions ----------</span></div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno"> 23</span> </div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno"> 24</span><span class="comment">// Implement two&#39;s complement addition and subtraction on int64s.</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno"> 25</span><span class="comment">//</span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno"> 26</span><span class="comment">// The C and C++ standards specify that the overflow of signed integers is</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno"> 27</span><span class="comment">// undefined. This is because of the different possible representations that may</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno"> 28</span><span class="comment">// be used for signed integers (one&#39;s complement, two&#39;s complement, sign and</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno"> 29</span><span class="comment">// magnitude). Such overflows are detected by Address Sanitizer with</span></div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno"> 30</span><span class="comment">// -fsanitize=signed-integer-overflow.</span></div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno"> 31</span><span class="comment">//</span></div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno"> 32</span><span class="comment">// Simple, portable overflow detection on current machines relies on</span></div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno"> 33</span><span class="comment">// these two functions. For example, if the sign of the sum of two positive</span></div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno"> 34</span><span class="comment">// integers is negative, there has been an overflow.</span></div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno"> 35</span><span class="comment">//</span></div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno"> 36</span><span class="comment">// Note that the static assert will break if the code is compiled on machines</span></div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno"> 37</span><span class="comment">// which do not use two&#39;s complement.</span></div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d"> 38</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">TwosComplementAddition</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno"> 39</span> <span class="keyword">static_assert</span>(<span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(-1LL) == ~0ULL,</div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno"> 40</span> <span class="stringliteral">&quot;The target architecture does not use two&#39;s complement.&quot;</span>);</div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno"> 41</span> <span class="keywordflow">return</span> absl::bit_cast&lt;int64_t&gt;(<span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(x) +</div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno"> 42</span> <span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(y));</div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno"> 43</span>}</div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno"> 44</span> </div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#ab7f89c34e63aca5f186808225f45865b"> 45</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#ab7f89c34e63aca5f186808225f45865b">TwosComplementSubtraction</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno"> 46</span> <span class="keyword">static_assert</span>(<span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(-1LL) == ~0ULL,</div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno"> 47</span> <span class="stringliteral">&quot;The target architecture does not use two&#39;s complement.&quot;</span>);</div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno"> 48</span> <span class="keywordflow">return</span> absl::bit_cast&lt;int64_t&gt;(<span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(x) -</div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno"> 49</span> <span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(y));</div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno"> 50</span>}</div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno"> 51</span> </div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno"> 52</span><span class="comment">// Helper function that returns true if an overflow has occurred in computing</span></div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno"> 53</span><span class="comment">// sum = x + y. sum is expected to be computed elsewhere.</span></div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa"> 54</a></span><span class="keyword">inline</span> <span class="keywordtype">bool</span> <a class="code hl_function" href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa">AddHadOverflow</a>(int64_t x, int64_t y, int64_t sum) {</div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno"> 55</span> <span class="comment">// Overflow cannot occur if operands have different signs.</span></div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno"> 56</span> <span class="comment">// It can only occur if sign(x) == sign(y) and sign(sum) != sign(x),</span></div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno"> 57</span> <span class="comment">// which is equivalent to: sign(x) != sign(sum) &amp;&amp; sign(y) != sign(sum).</span></div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno"> 58</span> <span class="comment">// This is captured when the expression below is negative.</span></div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno"> 59</span> <a class="code hl_define" href="base_2logging_8h.html#ae89df3243bbb8341130c7b3f44145ea0">DCHECK_EQ</a>(sum, <a class="code hl_function" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">TwosComplementAddition</a>(x, y));</div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno"> 60</span> <span class="keywordflow">return</span> ((x ^ sum) &amp; (y ^ sum)) &lt; 0;</div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno"> 61</span>}</div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno"> 62</span> </div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#ab5b3d385e40264b5c3094b64d10a2299"> 63</a></span><span class="keyword">inline</span> <span class="keywordtype">bool</span> <a class="code hl_function" href="namespaceoperations__research.html#ab5b3d385e40264b5c3094b64d10a2299">SubHadOverflow</a>(int64_t x, int64_t y, int64_t diff) {</div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno"> 64</span> <span class="comment">// This is the same reasoning as for AddHadOverflow. We have x = diff + y.</span></div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno"> 65</span> <span class="comment">// The formula is the same, with &#39;x&#39; and diff exchanged.</span></div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno"> 66</span> <a class="code hl_define" href="base_2logging_8h.html#ae89df3243bbb8341130c7b3f44145ea0">DCHECK_EQ</a>(diff, <a class="code hl_function" href="namespaceoperations__research.html#ab7f89c34e63aca5f186808225f45865b">TwosComplementSubtraction</a>(x, y));</div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno"> 67</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa">AddHadOverflow</a>(diff, y, x);</div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno"> 68</span>}</div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno"> 69</span> </div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno"> 70</span><span class="comment">// A note on overflow treatment.</span></div>
<div class="line"><a id="l00071" name="l00071"></a><span class="lineno"> 71</span><span class="comment">// kint64min and kint64max are treated as infinity.</span></div>
<div class="line"><a id="l00072" name="l00072"></a><span class="lineno"> 72</span><span class="comment">// Thus if the computation overflows, the result is always kint64m(ax/in).</span></div>
<div class="line"><a id="l00073" name="l00073"></a><span class="lineno"> 73</span><span class="comment">//</span></div>
<div class="line"><a id="l00074" name="l00074"></a><span class="lineno"> 74</span><span class="comment">// Note(user): this is actually wrong: when computing A-B, if A is kint64max</span></div>
<div class="line"><a id="l00075" name="l00075"></a><span class="lineno"> 75</span><span class="comment">// and B is finite, then A-B won&#39;t be kint64max: overflows aren&#39;t sticky.</span></div>
<div class="line"><a id="l00076" name="l00076"></a><span class="lineno"> 76</span><span class="comment">// TODO(user): consider making some operations overflow-sticky, some others</span></div>
<div class="line"><a id="l00077" name="l00077"></a><span class="lineno"> 77</span><span class="comment">// not, but make an explicit choice throughout.</span></div>
<div class="line"><a id="l00078" name="l00078"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a93bd93f028c18a4b55b30056ef60df44"> 78</a></span><span class="keyword">inline</span> <span class="keywordtype">bool</span> <a class="code hl_function" href="namespaceoperations__research.html#a93bd93f028c18a4b55b30056ef60df44">AddOverflows</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00079" name="l00079"></a><span class="lineno"> 79</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa">AddHadOverflow</a>(x, y, <a class="code hl_function" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">TwosComplementAddition</a>(x, y));</div>
<div class="line"><a id="l00080" name="l00080"></a><span class="lineno"> 80</span>}</div>
<div class="line"><a id="l00081" name="l00081"></a><span class="lineno"> 81</span> </div>
<div class="line"><a id="l00082" name="l00082"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a0004fd13375ee41f234051cb5cc74869"> 82</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#a0004fd13375ee41f234051cb5cc74869">SubOverflows</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00083" name="l00083"></a><span class="lineno"> 83</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#ab5b3d385e40264b5c3094b64d10a2299">SubHadOverflow</a>(x, y, <a class="code hl_function" href="namespaceoperations__research.html#ab7f89c34e63aca5f186808225f45865b">TwosComplementSubtraction</a>(x, y));</div>
<div class="line"><a id="l00084" name="l00084"></a><span class="lineno"> 84</span>}</div>
<div class="line"><a id="l00085" name="l00085"></a><span class="lineno"> 85</span> </div>
<div class="line"><a id="l00086" name="l00086"></a><span class="lineno"> 86</span><span class="comment">// Performs *b += a and returns false iff the addition overflow or underflow.</span></div>
<div class="line"><a id="l00087" name="l00087"></a><span class="lineno"> 87</span><span class="comment">// This function only works for typed integer type (IntType&lt;&gt;).</span></div>
<div class="line"><a id="l00088" name="l00088"></a><span class="lineno"> 88</span><span class="keyword">template</span> &lt;<span class="keyword">typename</span> IntegerType&gt;</div>
<div class="line"><a id="l00089" name="l00089"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#ae1bd0133149b70b678b123524541aaad"> 89</a></span><span class="keywordtype">bool</span> <a class="code hl_function" href="namespaceoperations__research.html#ae1bd0133149b70b678b123524541aaad">SafeAddInto</a>(IntegerType <a class="code hl_variable" href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a>, IntegerType* <a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a>) {</div>
<div class="line"><a id="l00090" name="l00090"></a><span class="lineno"> 90</span> <span class="keyword">const</span> int64_t x = <a class="code hl_variable" href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a>.value();</div>
<div class="line"><a id="l00091" name="l00091"></a><span class="lineno"> 91</span> <span class="keyword">const</span> int64_t y = <a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a>-&gt;value();</div>
<div class="line"><a id="l00092" name="l00092"></a><span class="lineno"> 92</span> <span class="keyword">const</span> int64_t sum = <a class="code hl_function" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">TwosComplementAddition</a>(x, y);</div>
<div class="line"><a id="l00093" name="l00093"></a><span class="lineno"> 93</span> <span class="keywordflow">if</span> (<a class="code hl_function" href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa">AddHadOverflow</a>(x, y, sum)) <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
<div class="line"><a id="l00094" name="l00094"></a><span class="lineno"> 94</span> *<a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a> = sum;</div>
<div class="line"><a id="l00095" name="l00095"></a><span class="lineno"> 95</span> <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
<div class="line"><a id="l00096" name="l00096"></a><span class="lineno"> 96</span>}</div>
<div class="line"><a id="l00097" name="l00097"></a><span class="lineno"> 97</span> </div>
<div class="line"><a id="l00098" name="l00098"></a><span class="lineno"> 98</span><span class="comment">// Returns kint64max if x &gt;= 0 and kint64min if x &lt; 0.</span></div>
<div class="line"><a id="l00099" name="l00099"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2"> 99</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(int64_t x) {</div>
<div class="line"><a id="l00100" name="l00100"></a><span class="lineno"> 100</span> <span class="comment">// return kint64max if x &gt;= 0 or kint64max + 1 (== kint64min) if x &lt; 0.</span></div>
<div class="line"><a id="l00101" name="l00101"></a><span class="lineno"> 101</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">TwosComplementAddition</a>(<a class="code hl_variable" href="integral__types_8h.html#a808bd435380aa1e2bbd6f13ac7759897">kint64max</a>, <span class="keyword">static_cast&lt;</span>int64_t<span class="keyword">&gt;</span>(x &lt; 0));</div>
<div class="line"><a id="l00102" name="l00102"></a><span class="lineno"> 102</span>}</div>
<div class="line"><a id="l00103" name="l00103"></a><span class="lineno"> 103</span> </div>
<div class="line"><a id="l00104" name="l00104"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a92790ebe58f31601890072ac2d4911c5"> 104</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#a92790ebe58f31601890072ac2d4911c5">CapAddGeneric</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00105" name="l00105"></a><span class="lineno"> 105</span> <span class="keyword">const</span> int64_t result = <a class="code hl_function" href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">TwosComplementAddition</a>(x, y);</div>
<div class="line"><a id="l00106" name="l00106"></a><span class="lineno"> 106</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa">AddHadOverflow</a>(x, y, result) ? <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(x) : result;</div>
<div class="line"><a id="l00107" name="l00107"></a><span class="lineno"> 107</span>}</div>
<div class="line"><a id="l00108" name="l00108"></a><span class="lineno"> 108</span> </div>
<div class="line"><a id="l00109" name="l00109"></a><span class="lineno"> 109</span><span class="preprocessor">#if defined(__GNUC__) &amp;&amp; defined(__x86_64__)</span></div>
<div class="line"><a id="l00110" name="l00110"></a><span class="lineno"> 110</span><span class="comment">// TODO(user): port this to other architectures.</span></div>
<div class="line"><a id="l00111" name="l00111"></a><span class="lineno"> 111</span><span class="keyword">inline</span> int64_t CapAddFast(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00112" name="l00112"></a><span class="lineno"> 112</span> <span class="keyword">const</span> int64_t cap = <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(x);</div>
<div class="line"><a id="l00113" name="l00113"></a><span class="lineno"> 113</span> int64_t result = x;</div>
<div class="line"><a id="l00114" name="l00114"></a><span class="lineno"> 114</span> <span class="comment">// clang-format off</span></div>
<div class="line"><a id="l00115" name="l00115"></a><span class="lineno"> 115</span> <span class="keyword">asm</span> <span class="keyword">volatile</span>( <span class="comment">// &#39;volatile&#39;: ask compiler optimizer &quot;keep as is&quot;.</span></div>
<div class="line"><a id="l00116" name="l00116"></a><span class="lineno"> 116</span> <span class="stringliteral">&quot;\t&quot;</span> <span class="stringliteral">&quot;addq %[y],%[result]&quot;</span></div>
<div class="line"><a id="l00117" name="l00117"></a><span class="lineno"> 117</span> <span class="stringliteral">&quot;\n\t&quot;</span> <span class="stringliteral">&quot;cmovoq %[cap],%[result]&quot;</span> <span class="comment">// Conditional move if overflow.</span></div>
<div class="line"><a id="l00118" name="l00118"></a><span class="lineno"> 118</span> : [result] <span class="stringliteral">&quot;=r&quot;</span>(result) <span class="comment">// Output</span></div>
<div class="line"><a id="l00119" name="l00119"></a><span class="lineno"> 119</span> : <span class="stringliteral">&quot;[result]&quot;</span> (result), [y] <span class="stringliteral">&quot;r&quot;</span>(y), [cap] <span class="stringliteral">&quot;r&quot;</span>(cap) <span class="comment">// Input.</span></div>
<div class="line"><a id="l00120" name="l00120"></a><span class="lineno"> 120</span> : <span class="stringliteral">&quot;cc&quot;</span> <span class="comment">/* Clobbered registers */</span> );</div>
<div class="line"><a id="l00121" name="l00121"></a><span class="lineno"> 121</span> <span class="comment">// clang-format on</span></div>
<div class="line"><a id="l00122" name="l00122"></a><span class="lineno"> 122</span> <span class="keywordflow">return</span> result;</div>
<div class="line"><a id="l00123" name="l00123"></a><span class="lineno"> 123</span>}</div>
<div class="line"><a id="l00124" name="l00124"></a><span class="lineno"> 124</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00125" name="l00125"></a><span class="lineno"> 125</span> </div>
<div class="line"><a id="l00126" name="l00126"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a111f44b9b9cf67a8e8d83794ac9f5291"> 126</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#a111f44b9b9cf67a8e8d83794ac9f5291">CapAdd</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00127" name="l00127"></a><span class="lineno"> 127</span><span class="preprocessor">#if defined(__GNUC__) &amp;&amp; defined(__x86_64__)</span></div>
<div class="line"><a id="l00128" name="l00128"></a><span class="lineno"> 128</span> <span class="keywordflow">return</span> CapAddFast(x, y);</div>
<div class="line"><a id="l00129" name="l00129"></a><span class="lineno"> 129</span><span class="preprocessor">#else</span></div>
<div class="line"><a id="l00130" name="l00130"></a><span class="lineno"> 130</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#a92790ebe58f31601890072ac2d4911c5">CapAddGeneric</a>(x, y);</div>
<div class="line"><a id="l00131" name="l00131"></a><span class="lineno"> 131</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00132" name="l00132"></a><span class="lineno"> 132</span>}</div>
<div class="line"><a id="l00133" name="l00133"></a><span class="lineno"> 133</span> </div>
<div class="line"><a id="l00134" name="l00134"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a1e489359fd31c3ef24a113fce05c08ee"> 134</a></span><span class="keyword">inline</span> <span class="keywordtype">void</span> <a class="code hl_function" href="namespaceoperations__research.html#a1e489359fd31c3ef24a113fce05c08ee">CapAddTo</a>(int64_t x, int64_t* y) { *y = <a class="code hl_function" href="namespaceoperations__research.html#a111f44b9b9cf67a8e8d83794ac9f5291">CapAdd</a>(*y, x); }</div>
<div class="line"><a id="l00135" name="l00135"></a><span class="lineno"> 135</span> </div>
<div class="line"><a id="l00136" name="l00136"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#af226a644c66eca0d1ce8885529f9f5a1"> 136</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#af226a644c66eca0d1ce8885529f9f5a1">CapSubGeneric</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00137" name="l00137"></a><span class="lineno"> 137</span> <span class="keyword">const</span> int64_t result = <a class="code hl_function" href="namespaceoperations__research.html#ab7f89c34e63aca5f186808225f45865b">TwosComplementSubtraction</a>(x, y);</div>
<div class="line"><a id="l00138" name="l00138"></a><span class="lineno"> 138</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#ab5b3d385e40264b5c3094b64d10a2299">SubHadOverflow</a>(x, y, result) ? <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(x) : result;</div>
<div class="line"><a id="l00139" name="l00139"></a><span class="lineno"> 139</span>}</div>
<div class="line"><a id="l00140" name="l00140"></a><span class="lineno"> 140</span> </div>
<div class="line"><a id="l00141" name="l00141"></a><span class="lineno"> 141</span><span class="preprocessor">#if defined(__GNUC__) &amp;&amp; defined(__x86_64__)</span></div>
<div class="line"><a id="l00142" name="l00142"></a><span class="lineno"> 142</span><span class="comment">// TODO(user): port this to other architectures.</span></div>
<div class="line"><a id="l00143" name="l00143"></a><span class="lineno"> 143</span><span class="keyword">inline</span> int64_t CapSubFast(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00144" name="l00144"></a><span class="lineno"> 144</span> <span class="keyword">const</span> int64_t cap = <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(x);</div>
<div class="line"><a id="l00145" name="l00145"></a><span class="lineno"> 145</span> int64_t result = x;</div>
<div class="line"><a id="l00146" name="l00146"></a><span class="lineno"> 146</span> <span class="comment">// clang-format off</span></div>
<div class="line"><a id="l00147" name="l00147"></a><span class="lineno"> 147</span> <span class="keyword">asm</span> <span class="keyword">volatile</span>( <span class="comment">// &#39;volatile&#39;: ask compiler optimizer &quot;keep as is&quot;.</span></div>
<div class="line"><a id="l00148" name="l00148"></a><span class="lineno"> 148</span> <span class="stringliteral">&quot;\t&quot;</span> <span class="stringliteral">&quot;subq %[y],%[result]&quot;</span></div>
<div class="line"><a id="l00149" name="l00149"></a><span class="lineno"> 149</span> <span class="stringliteral">&quot;\n\t&quot;</span> <span class="stringliteral">&quot;cmovoq %[cap],%[result]&quot;</span> <span class="comment">// Conditional move if overflow.</span></div>
<div class="line"><a id="l00150" name="l00150"></a><span class="lineno"> 150</span> : [result] <span class="stringliteral">&quot;=r&quot;</span>(result) <span class="comment">// Output</span></div>
<div class="line"><a id="l00151" name="l00151"></a><span class="lineno"> 151</span> : <span class="stringliteral">&quot;[result]&quot;</span> (result), [y] <span class="stringliteral">&quot;r&quot;</span>(y), [cap] <span class="stringliteral">&quot;r&quot;</span>(cap) <span class="comment">// Input.</span></div>
<div class="line"><a id="l00152" name="l00152"></a><span class="lineno"> 152</span> : <span class="stringliteral">&quot;cc&quot;</span> <span class="comment">/* Clobbered registers */</span> );</div>
<div class="line"><a id="l00153" name="l00153"></a><span class="lineno"> 153</span> <span class="comment">// clang-format on</span></div>
<div class="line"><a id="l00154" name="l00154"></a><span class="lineno"> 154</span> <span class="keywordflow">return</span> result;</div>
<div class="line"><a id="l00155" name="l00155"></a><span class="lineno"> 155</span>}</div>
<div class="line"><a id="l00156" name="l00156"></a><span class="lineno"> 156</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00157" name="l00157"></a><span class="lineno"> 157</span> </div>
<div class="line"><a id="l00158" name="l00158"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#a4a43d435871f16c321861fa5de32df82"> 158</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#a4a43d435871f16c321861fa5de32df82">CapSub</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00159" name="l00159"></a><span class="lineno"> 159</span><span class="preprocessor">#if defined(__GNUC__) &amp;&amp; defined(__x86_64__)</span></div>
<div class="line"><a id="l00160" name="l00160"></a><span class="lineno"> 160</span> <span class="keywordflow">return</span> CapSubFast(x, y);</div>
<div class="line"><a id="l00161" name="l00161"></a><span class="lineno"> 161</span><span class="preprocessor">#else</span></div>
<div class="line"><a id="l00162" name="l00162"></a><span class="lineno"> 162</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#af226a644c66eca0d1ce8885529f9f5a1">CapSubGeneric</a>(x, y);</div>
<div class="line"><a id="l00163" name="l00163"></a><span class="lineno"> 163</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00164" name="l00164"></a><span class="lineno"> 164</span>}</div>
<div class="line"><a id="l00165" name="l00165"></a><span class="lineno"> 165</span> </div>
<div class="line"><a id="l00166" name="l00166"></a><span class="lineno"> 166</span><span class="comment">// Note(user): -kint64min != kint64max, but kint64max == ~kint64min.</span></div>
<div class="line"><a id="l00167" name="l00167"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#af979bdbf1d7d690ae24e97ad456297d2"> 167</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#af979bdbf1d7d690ae24e97ad456297d2">CapOpp</a>(int64_t v) { <span class="keywordflow">return</span> v == <a class="code hl_variable" href="integral__types_8h.html#af8b05f1b3a4c4ef94dd184c6c31a56e6">kint64min</a> ? ~v : -v; }</div>
<div class="line"><a id="l00168" name="l00168"></a><span class="lineno"> 168</span> </div>
<div class="line"><a id="l00169" name="l00169"></a><span class="lineno"><a class="line" href="namespaceoperations__research_1_1cap__prod__util.html"> 169</a></span><span class="keyword">namespace </span>cap_prod_util {</div>
<div class="line"><a id="l00170" name="l00170"></a><span class="lineno"> 170</span><span class="comment">// Returns an unsigned int equal to the absolute value of n, in a way that</span></div>
<div class="line"><a id="l00171" name="l00171"></a><span class="lineno"> 171</span><span class="comment">// will not produce overflows.</span></div>
<div class="line"><a id="l00172" name="l00172"></a><span class="lineno"><a class="line" href="namespaceoperations__research_1_1cap__prod__util.html#ad6bc7f73c7f1b8854f5a0c3f3bd02db5"> 172</a></span><span class="keyword">inline</span> uint64_t <a class="code hl_function" href="namespaceoperations__research_1_1cap__prod__util.html#ad6bc7f73c7f1b8854f5a0c3f3bd02db5">uint_abs</a>(int64_t n) {</div>
<div class="line"><a id="l00173" name="l00173"></a><span class="lineno"> 173</span> <span class="keywordflow">return</span> n &lt; 0 ? ~static_cast&lt;uint64_t&gt;(n) + 1 : <span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(n);</div>
<div class="line"><a id="l00174" name="l00174"></a><span class="lineno"> 174</span>}</div>
<div class="line"><a id="l00175" name="l00175"></a><span class="lineno"> 175</span>} <span class="comment">// namespace cap_prod_util</span></div>
<div class="line"><a id="l00176" name="l00176"></a><span class="lineno"> 176</span> </div>
<div class="line"><a id="l00177" name="l00177"></a><span class="lineno"> 177</span><span class="comment">// The generic algorithm computes a bound on the number of bits necessary to</span></div>
<div class="line"><a id="l00178" name="l00178"></a><span class="lineno"> 178</span><span class="comment">// store the result. For this it uses the position of the most significant bits</span></div>
<div class="line"><a id="l00179" name="l00179"></a><span class="lineno"> 179</span><span class="comment">// of each of the arguments.</span></div>
<div class="line"><a id="l00180" name="l00180"></a><span class="lineno"> 180</span><span class="comment">// If the result needs at least 64 bits, then return a capped value.</span></div>
<div class="line"><a id="l00181" name="l00181"></a><span class="lineno"> 181</span><span class="comment">// If the result needs at most 63 bits, then return the product.</span></div>
<div class="line"><a id="l00182" name="l00182"></a><span class="lineno"> 182</span><span class="comment">// Otherwise, the result may use 63 or 64 bits: compute the product</span></div>
<div class="line"><a id="l00183" name="l00183"></a><span class="lineno"> 183</span><span class="comment">// as a uint64_t, and cap it if necessary.</span></div>
<div class="line"><a id="l00184" name="l00184"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#adfcad7c607afe2de123ac91fcd2b87c0"> 184</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#adfcad7c607afe2de123ac91fcd2b87c0">CapProdGeneric</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00185" name="l00185"></a><span class="lineno"> 185</span> <span class="keyword">const</span> uint64_t <a class="code hl_variable" href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a> = <a class="code hl_function" href="namespaceoperations__research_1_1cap__prod__util.html#ad6bc7f73c7f1b8854f5a0c3f3bd02db5">cap_prod_util::uint_abs</a>(x);</div>
<div class="line"><a id="l00186" name="l00186"></a><span class="lineno"> 186</span> <span class="keyword">const</span> uint64_t <a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a> = <a class="code hl_function" href="namespaceoperations__research_1_1cap__prod__util.html#ad6bc7f73c7f1b8854f5a0c3f3bd02db5">cap_prod_util::uint_abs</a>(y);</div>
<div class="line"><a id="l00187" name="l00187"></a><span class="lineno"> 187</span> <span class="comment">// Let MSB(x) denote the most significant bit of x. We have:</span></div>
<div class="line"><a id="l00188" name="l00188"></a><span class="lineno"> 188</span> <span class="comment">// MSB(x) + MSB(y) &lt;= MSB(x * y) &lt;= MSB(x) + MSB(y) + 1</span></div>
<div class="line"><a id="l00189" name="l00189"></a><span class="lineno"> 189</span> <span class="keyword">const</span> <span class="keywordtype">int</span> msb_sum =</div>
<div class="line"><a id="l00190" name="l00190"></a><span class="lineno"> 190</span> <a class="code hl_function" href="namespaceoperations__research.html#afa6ef9aef70f95b9d5bcee2c10937bc8">MostSignificantBitPosition64</a>(<a class="code hl_variable" href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a>) + <a class="code hl_function" href="namespaceoperations__research.html#afa6ef9aef70f95b9d5bcee2c10937bc8">MostSignificantBitPosition64</a>(<a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a>);</div>
<div class="line"><a id="l00191" name="l00191"></a><span class="lineno"> 191</span> <span class="keyword">const</span> <span class="keywordtype">int</span> kMaxBitIndexInInt64 = 63;</div>
<div class="line"><a id="l00192" name="l00192"></a><span class="lineno"> 192</span> <span class="keywordflow">if</span> (msb_sum &lt;= kMaxBitIndexInInt64 - 2) <span class="keywordflow">return</span> x * y;</div>
<div class="line"><a id="l00193" name="l00193"></a><span class="lineno"> 193</span> <span class="comment">// Catch a == 0 or b == 0 now, as MostSignificantBitPosition64(0) == 0.</span></div>
<div class="line"><a id="l00194" name="l00194"></a><span class="lineno"> 194</span> <span class="comment">// TODO(user): avoid this by writing function Log2(a) with Log2(0) == -1.</span></div>
<div class="line"><a id="l00195" name="l00195"></a><span class="lineno"> 195</span> <span class="keywordflow">if</span> (<a class="code hl_variable" href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a> == 0 || <a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a> == 0) <span class="keywordflow">return</span> 0;</div>
<div class="line"><a id="l00196" name="l00196"></a><span class="lineno"> 196</span> <span class="keyword">const</span> int64_t cap = <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(x ^ y);</div>
<div class="line"><a id="l00197" name="l00197"></a><span class="lineno"> 197</span> <span class="keywordflow">if</span> (msb_sum &gt;= kMaxBitIndexInInt64) <span class="keywordflow">return</span> cap;</div>
<div class="line"><a id="l00198" name="l00198"></a><span class="lineno"> 198</span> <span class="comment">// The corner case is when msb_sum == 62, i.e. at least 63 bits will be</span></div>
<div class="line"><a id="l00199" name="l00199"></a><span class="lineno"> 199</span> <span class="comment">// needed to store the product. The following product will never overflow</span></div>
<div class="line"><a id="l00200" name="l00200"></a><span class="lineno"> 200</span> <span class="comment">// on uint64_t, since msb_sum == 62.</span></div>
<div class="line"><a id="l00201" name="l00201"></a><span class="lineno"> 201</span> <span class="keyword">const</span> uint64_t u_prod = <a class="code hl_variable" href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a> * <a class="code hl_variable" href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a>;</div>
<div class="line"><a id="l00202" name="l00202"></a><span class="lineno"> 202</span> <span class="comment">// The overflow cases are captured by one of the following conditions:</span></div>
<div class="line"><a id="l00203" name="l00203"></a><span class="lineno"> 203</span> <span class="comment">// (cap &gt;= 0 &amp;&amp; u_prod &gt;= static_cast&lt;uint64_t&gt;(kint64max) or</span></div>
<div class="line"><a id="l00204" name="l00204"></a><span class="lineno"> 204</span> <span class="comment">// (cap &lt; 0 &amp;&amp; u_prod &gt;= static_cast&lt;uint64_t&gt;(kint64min)).</span></div>
<div class="line"><a id="l00205" name="l00205"></a><span class="lineno"> 205</span> <span class="comment">// These can be optimized as follows (and if the condition is false, it is</span></div>
<div class="line"><a id="l00206" name="l00206"></a><span class="lineno"> 206</span> <span class="comment">// safe to compute x * y.</span></div>
<div class="line"><a id="l00207" name="l00207"></a><span class="lineno"> 207</span> <span class="keywordflow">if</span> (u_prod &gt;= <span class="keyword">static_cast&lt;</span>uint64_t<span class="keyword">&gt;</span>(cap)) <span class="keywordflow">return</span> cap;</div>
<div class="line"><a id="l00208" name="l00208"></a><span class="lineno"> 208</span> <span class="keyword">const</span> int64_t abs_result = absl::bit_cast&lt;int64_t&gt;(u_prod);</div>
<div class="line"><a id="l00209" name="l00209"></a><span class="lineno"> 209</span> <span class="keywordflow">return</span> cap &lt; 0 ? -abs_result : abs_result;</div>
<div class="line"><a id="l00210" name="l00210"></a><span class="lineno"> 210</span>}</div>
<div class="line"><a id="l00211" name="l00211"></a><span class="lineno"> 211</span> </div>
<div class="line"><a id="l00212" name="l00212"></a><span class="lineno"> 212</span><span class="preprocessor">#if defined(__GNUC__) &amp;&amp; defined(__x86_64__)</span></div>
<div class="line"><a id="l00213" name="l00213"></a><span class="lineno"> 213</span><span class="comment">// TODO(user): port this to other architectures.</span></div>
<div class="line"><a id="l00214" name="l00214"></a><span class="lineno"> 214</span><span class="keyword">inline</span> int64_t CapProdFast(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00215" name="l00215"></a><span class="lineno"> 215</span> <span class="comment">// cap = kint64max if x and y have the same sign, cap = kint64min</span></div>
<div class="line"><a id="l00216" name="l00216"></a><span class="lineno"> 216</span> <span class="comment">// otherwise.</span></div>
<div class="line"><a id="l00217" name="l00217"></a><span class="lineno"> 217</span> <span class="keyword">const</span> int64_t cap = <a class="code hl_function" href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">CapWithSignOf</a>(x ^ y);</div>
<div class="line"><a id="l00218" name="l00218"></a><span class="lineno"> 218</span> int64_t result = x;</div>
<div class="line"><a id="l00219" name="l00219"></a><span class="lineno"> 219</span> <span class="comment">// Here, we use the fact that imul of two signed 64-integers returns a 128-bit</span></div>
<div class="line"><a id="l00220" name="l00220"></a><span class="lineno"> 220</span> <span class="comment">// result -- we care about the lower 64 bits. More importantly, imul also sets</span></div>
<div class="line"><a id="l00221" name="l00221"></a><span class="lineno"> 221</span> <span class="comment">// the carry flag if 64 bits were not enough.</span></div>
<div class="line"><a id="l00222" name="l00222"></a><span class="lineno"> 222</span> <span class="comment">// We therefore use cmovc to return cap if the carry was set.</span></div>
<div class="line"><a id="l00223" name="l00223"></a><span class="lineno"> 223</span> <span class="comment">// clang-format off</span></div>
<div class="line"><a id="l00224" name="l00224"></a><span class="lineno"> 224</span> <span class="keyword">asm</span> <span class="keyword">volatile</span>( <span class="comment">// &#39;volatile&#39;: ask compiler optimizer &quot;keep as is&quot;.</span></div>
<div class="line"><a id="l00225" name="l00225"></a><span class="lineno"> 225</span> <span class="stringliteral">&quot;\n\t&quot;</span> <span class="stringliteral">&quot;imulq %[y],%[result]&quot;</span></div>
<div class="line"><a id="l00226" name="l00226"></a><span class="lineno"> 226</span> <span class="stringliteral">&quot;\n\t&quot;</span> <span class="stringliteral">&quot;cmovcq %[cap],%[result]&quot;</span> <span class="comment">// Conditional move if carry.</span></div>
<div class="line"><a id="l00227" name="l00227"></a><span class="lineno"> 227</span> : [result] <span class="stringliteral">&quot;=r&quot;</span>(result) <span class="comment">// Output</span></div>
<div class="line"><a id="l00228" name="l00228"></a><span class="lineno"> 228</span> : <span class="stringliteral">&quot;[result]&quot;</span> (result), [y] <span class="stringliteral">&quot;r&quot;</span>(y), [cap] <span class="stringliteral">&quot;r&quot;</span>(cap) <span class="comment">// Input.</span></div>
<div class="line"><a id="l00229" name="l00229"></a><span class="lineno"> 229</span> : <span class="stringliteral">&quot;cc&quot;</span> <span class="comment">/* Clobbered registers */</span>);</div>
<div class="line"><a id="l00230" name="l00230"></a><span class="lineno"> 230</span> <span class="comment">// clang-format on</span></div>
<div class="line"><a id="l00231" name="l00231"></a><span class="lineno"> 231</span> <span class="keywordflow">return</span> result;</div>
<div class="line"><a id="l00232" name="l00232"></a><span class="lineno"> 232</span>}</div>
<div class="line"><a id="l00233" name="l00233"></a><span class="lineno"> 233</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00234" name="l00234"></a><span class="lineno"> 234</span> </div>
<div class="line"><a id="l00235" name="l00235"></a><span class="lineno"><a class="line" href="namespaceoperations__research.html#aa64bf49d041052c7cb3f40f7496d7534"> 235</a></span><span class="keyword">inline</span> int64_t <a class="code hl_function" href="namespaceoperations__research.html#aa64bf49d041052c7cb3f40f7496d7534">CapProd</a>(int64_t x, int64_t y) {</div>
<div class="line"><a id="l00236" name="l00236"></a><span class="lineno"> 236</span><span class="preprocessor">#if defined(__GNUC__) &amp;&amp; defined(__x86_64__)</span></div>
<div class="line"><a id="l00237" name="l00237"></a><span class="lineno"> 237</span> <span class="keywordflow">return</span> CapProdFast(x, y);</div>
<div class="line"><a id="l00238" name="l00238"></a><span class="lineno"> 238</span><span class="preprocessor">#else</span></div>
<div class="line"><a id="l00239" name="l00239"></a><span class="lineno"> 239</span> <span class="keywordflow">return</span> <a class="code hl_function" href="namespaceoperations__research.html#adfcad7c607afe2de123ac91fcd2b87c0">CapProdGeneric</a>(x, y);</div>
<div class="line"><a id="l00240" name="l00240"></a><span class="lineno"> 240</span><span class="preprocessor">#endif</span></div>
<div class="line"><a id="l00241" name="l00241"></a><span class="lineno"> 241</span>}</div>
<div class="line"><a id="l00242" name="l00242"></a><span class="lineno"> 242</span>} <span class="comment">// namespace operations_research</span></div>
<div class="line"><a id="l00243" name="l00243"></a><span class="lineno"> 243</span> </div>
<div class="line"><a id="l00244" name="l00244"></a><span class="lineno"> 244</span><span class="preprocessor">#endif </span><span class="comment">// OR_TOOLS_UTIL_SATURATED_ARITHMETIC_H_</span></div>
2022-03-04 00:11:33 +01:00
<div class="ttc" id="abase_2logging_8h_html_ae89df3243bbb8341130c7b3f44145ea0"><div class="ttname"><a href="base_2logging_8h.html#ae89df3243bbb8341130c7b3f44145ea0">DCHECK_EQ</a></div><div class="ttdeci">#define DCHECK_EQ(val1, val2)</div><div class="ttdef"><b>Definition:</b> <a href="base_2logging_8h_source.html#l00891">base/logging.h:891</a></div></div>
2022-01-17 21:42:14 +01:00
<div class="ttc" id="abitset_8h_html"><div class="ttname"><a href="bitset_8h.html">bitset.h</a></div></div>
<div class="ttc" id="aconstraint__solver_2table_8cc_html_a9293e4d29cac928301645070dd307683"><div class="ttname"><a href="constraint__solver_2table_8cc.html#a9293e4d29cac928301645070dd307683">b</a></div><div class="ttdeci">int64_t b</div><div class="ttdef"><b>Definition:</b> <a href="constraint__solver_2table_8cc_source.html#l00047">constraint_solver/table.cc:47</a></div></div>
<div class="ttc" id="aconstraint__solver_2table_8cc_html_acb18315d548212835cd8ed4287e6c0b6"><div class="ttname"><a href="constraint__solver_2table_8cc.html#acb18315d548212835cd8ed4287e6c0b6">a</a></div><div class="ttdeci">int64_t a</div><div class="ttdef"><b>Definition:</b> <a href="constraint__solver_2table_8cc_source.html#l00046">constraint_solver/table.cc:46</a></div></div>
<div class="ttc" id="aintegral__types_8h_html"><div class="ttname"><a href="integral__types_8h.html">integral_types.h</a></div></div>
<div class="ttc" id="aintegral__types_8h_html_a808bd435380aa1e2bbd6f13ac7759897"><div class="ttname"><a href="integral__types_8h.html#a808bd435380aa1e2bbd6f13ac7759897">kint64max</a></div><div class="ttdeci">static const int64_t kint64max</div><div class="ttdef"><b>Definition:</b> <a href="integral__types_8h_source.html#l00032">integral_types.h:32</a></div></div>
<div class="ttc" id="aintegral__types_8h_html_af8b05f1b3a4c4ef94dd184c6c31a56e6"><div class="ttname"><a href="integral__types_8h.html#af8b05f1b3a4c4ef94dd184c6c31a56e6">kint64min</a></div><div class="ttdeci">static const int64_t kint64min</div><div class="ttdef"><b>Definition:</b> <a href="integral__types_8h_source.html#l00031">integral_types.h:31</a></div></div>
<div class="ttc" id="anamespaceoperations__research_1_1cap__prod__util_html_ad6bc7f73c7f1b8854f5a0c3f3bd02db5"><div class="ttname"><a href="namespaceoperations__research_1_1cap__prod__util.html#ad6bc7f73c7f1b8854f5a0c3f3bd02db5">operations_research::cap_prod_util::uint_abs</a></div><div class="ttdeci">uint64_t uint_abs(int64_t n)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00172">saturated_arithmetic.h:172</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html"><div class="ttname"><a href="namespaceoperations__research.html">operations_research</a></div><div class="ttdoc">Collection of objects used to extend the Constraint Solver library.</div><div class="ttdef"><b>Definition:</b> <a href="dense__doubly__linked__list_8h_source.html#l00021">dense_doubly_linked_list.h:21</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a0004fd13375ee41f234051cb5cc74869"><div class="ttname"><a href="namespaceoperations__research.html#a0004fd13375ee41f234051cb5cc74869">operations_research::SubOverflows</a></div><div class="ttdeci">int64_t SubOverflows(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00082">saturated_arithmetic.h:82</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a0d130d7d0baf49b66a6938714828d0aa"><div class="ttname"><a href="namespaceoperations__research.html#a0d130d7d0baf49b66a6938714828d0aa">operations_research::AddHadOverflow</a></div><div class="ttdeci">bool AddHadOverflow(int64_t x, int64_t y, int64_t sum)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00054">saturated_arithmetic.h:54</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a111f44b9b9cf67a8e8d83794ac9f5291"><div class="ttname"><a href="namespaceoperations__research.html#a111f44b9b9cf67a8e8d83794ac9f5291">operations_research::CapAdd</a></div><div class="ttdeci">int64_t CapAdd(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00126">saturated_arithmetic.h:126</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a1e489359fd31c3ef24a113fce05c08ee"><div class="ttname"><a href="namespaceoperations__research.html#a1e489359fd31c3ef24a113fce05c08ee">operations_research::CapAddTo</a></div><div class="ttdeci">void CapAddTo(int64_t x, int64_t *y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00134">saturated_arithmetic.h:134</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a28f4f86e4cc6cfc5e075577baabd00f2"><div class="ttname"><a href="namespaceoperations__research.html#a28f4f86e4cc6cfc5e075577baabd00f2">operations_research::CapWithSignOf</a></div><div class="ttdeci">int64_t CapWithSignOf(int64_t x)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00099">saturated_arithmetic.h:99</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a2e03c61d96b37a3533c3ffcec93fc18d"><div class="ttname"><a href="namespaceoperations__research.html#a2e03c61d96b37a3533c3ffcec93fc18d">operations_research::TwosComplementAddition</a></div><div class="ttdeci">int64_t TwosComplementAddition(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00038">saturated_arithmetic.h:38</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a4a43d435871f16c321861fa5de32df82"><div class="ttname"><a href="namespaceoperations__research.html#a4a43d435871f16c321861fa5de32df82">operations_research::CapSub</a></div><div class="ttdeci">int64_t CapSub(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00158">saturated_arithmetic.h:158</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a92790ebe58f31601890072ac2d4911c5"><div class="ttname"><a href="namespaceoperations__research.html#a92790ebe58f31601890072ac2d4911c5">operations_research::CapAddGeneric</a></div><div class="ttdeci">int64_t CapAddGeneric(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00104">saturated_arithmetic.h:104</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_a93bd93f028c18a4b55b30056ef60df44"><div class="ttname"><a href="namespaceoperations__research.html#a93bd93f028c18a4b55b30056ef60df44">operations_research::AddOverflows</a></div><div class="ttdeci">bool AddOverflows(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00078">saturated_arithmetic.h:78</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_aa64bf49d041052c7cb3f40f7496d7534"><div class="ttname"><a href="namespaceoperations__research.html#aa64bf49d041052c7cb3f40f7496d7534">operations_research::CapProd</a></div><div class="ttdeci">int64_t CapProd(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00235">saturated_arithmetic.h:235</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_ab5b3d385e40264b5c3094b64d10a2299"><div class="ttname"><a href="namespaceoperations__research.html#ab5b3d385e40264b5c3094b64d10a2299">operations_research::SubHadOverflow</a></div><div class="ttdeci">bool SubHadOverflow(int64_t x, int64_t y, int64_t diff)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00063">saturated_arithmetic.h:63</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_ab7f89c34e63aca5f186808225f45865b"><div class="ttname"><a href="namespaceoperations__research.html#ab7f89c34e63aca5f186808225f45865b">operations_research::TwosComplementSubtraction</a></div><div class="ttdeci">int64_t TwosComplementSubtraction(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00045">saturated_arithmetic.h:45</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_adfcad7c607afe2de123ac91fcd2b87c0"><div class="ttname"><a href="namespaceoperations__research.html#adfcad7c607afe2de123ac91fcd2b87c0">operations_research::CapProdGeneric</a></div><div class="ttdeci">int64_t CapProdGeneric(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00184">saturated_arithmetic.h:184</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_ae1bd0133149b70b678b123524541aaad"><div class="ttname"><a href="namespaceoperations__research.html#ae1bd0133149b70b678b123524541aaad">operations_research::SafeAddInto</a></div><div class="ttdeci">bool SafeAddInto(IntegerType a, IntegerType *b)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00089">saturated_arithmetic.h:89</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_af226a644c66eca0d1ce8885529f9f5a1"><div class="ttname"><a href="namespaceoperations__research.html#af226a644c66eca0d1ce8885529f9f5a1">operations_research::CapSubGeneric</a></div><div class="ttdeci">int64_t CapSubGeneric(int64_t x, int64_t y)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00136">saturated_arithmetic.h:136</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_af979bdbf1d7d690ae24e97ad456297d2"><div class="ttname"><a href="namespaceoperations__research.html#af979bdbf1d7d690ae24e97ad456297d2">operations_research::CapOpp</a></div><div class="ttdeci">int64_t CapOpp(int64_t v)</div><div class="ttdef"><b>Definition:</b> <a href="saturated__arithmetic_8h_source.html#l00167">saturated_arithmetic.h:167</a></div></div>
<div class="ttc" id="anamespaceoperations__research_html_afa6ef9aef70f95b9d5bcee2c10937bc8"><div class="ttname"><a href="namespaceoperations__research.html#afa6ef9aef70f95b9d5bcee2c10937bc8">operations_research::MostSignificantBitPosition64</a></div><div class="ttdeci">int MostSignificantBitPosition64(uint64_t n)</div><div class="ttdef"><b>Definition:</b> <a href="bitset_8h_source.html#l00231">bitset.h:231</a></div></div>
2021-01-26 11:28:50 +01:00
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