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    <p><s>Honestly, who cares??</s></p> <p>[Edit:] This actually turned out somewhat interesting. Contrary to my initial assumption, in <em>unoptimized</em> compilation, <code>n += b;</code> is better than <code>n += b ? 1 : 0;</code>. However, with optimizations, the two are identical. More importantly, though, the optimized version of this form is always better than <code>if (b) ++n;</code>, which <em>always</em> creates a <code>cmp/je</code> instruction. [/Edit]</p> <p>If you're terribly curious, put the following code through your compiler and compare the resulting assembly! (Be sure to test various optimization settings.)</p> <pre><code>int n; void f(bool b) { n += b ? 1 : 0; } void g(bool b) { if (b) ++n; } </code></pre> <p>I tested it with GCC 4.6.1: With <code>g++</code> and with no optimization, <code>g()</code> is shorter. With <code>-O3</code>, however, <code>f()</code> is shorter:</p> <pre><code>g(): f(): cmpb $0, 4(%esp) movzbl 4(%esp), %eax je .L1 addl %eax, n addl $1, n .L1: rep </code></pre> <p>Note that the optimization for <code>f()</code> actually does what you wrote originally: It literally adds the value of the conditional to <code>n</code>. This is in C++ of course. It'd be interesting to see what the C compiler would do, absent a <code>bool</code> type.</p> <p>Another note, since you tagged this C as well: In C, if you don't use bools (from <code>&lt;stdbool.h&gt;</code>) but rather <code>int</code>s, then the advantage of one version over the other disappears, since both now have to do some sort of testing.</p>
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    1. COah ! Thank you !
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    2. COThe assembly will tell you whether it's skipping the add, but it won't tell you if that's faster.
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      1. USMark Ransom
    3. COKerrek: Could you post both `f()` and `g()` at no optimization and -O3? I'm surprised that gcc doesn't compile these the same at `-03`.
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