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Commit216af5e

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Make bitmapset.c use 64-bit bitmap words on 64-bit machines.
Using the full width of the CPU's native word size shouldn't costanything in typical cases. When working with large bitmapsets,this halves the number of operations needed for many common BMSoperations. On the right sort of test case, a measurable improvementis obtained.David RowleyDiscussion:https://postgr.es/m/CAKJS1f9EGBd2h-VkXvb=51tf+X46zMX5T8h-KYgXEV_u2zmLUw@mail.gmail.com
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‎src/include/nodes/bitmapset.h

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@@ -27,13 +27,25 @@ struct List;
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/*
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* Data representation
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*
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* Larger bitmap word sizes generally give better performance, so long as
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* they're not wider than the processor can handle efficiently. We use
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* 64-bit words if pointers are that large, else 32-bit words.
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*/
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#ifSIZEOF_VOID_P >=8
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#defineBITS_PER_BITMAPWORD 64
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typedefuint64bitmapword;/* must be an unsigned type */
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typedefint64signedbitmapword;/* must be the matching signed type */
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#else
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/* The unit size can be adjusted by changing these three declarations: */
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#defineBITS_PER_BITMAPWORD 32
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typedefuint32bitmapword;/* must be an unsigned type */
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typedefint32signedbitmapword;/* must be the matching signed type */
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#endif
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typedefstructBitmapset
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{
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intnwords;/* number of words in array */

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