From dbb4eab9f3efbcee2326278be6f70ff52685b2b0 Mon Sep 17 00:00:00 2001 From: Dmitrii Dolgov <9erthalion6@gmail.com> Date: Fri, 17 Feb 2023 10:17:55 +0100 Subject: [PATCH v13 1/2] Reusable decimalLength functions Move out decimalLength functions to reuse in the following patch. --- src/backend/utils/adt/numutils.c | 50 +----------------------- src/include/utils/numutils.h | 67 ++++++++++++++++++++++++++++++++ 2 files changed, 68 insertions(+), 49 deletions(-) create mode 100644 src/include/utils/numutils.h diff --git a/src/backend/utils/adt/numutils.c b/src/backend/utils/adt/numutils.c index 471fbb7ee6..df7418cce7 100644 --- a/src/backend/utils/adt/numutils.c +++ b/src/backend/utils/adt/numutils.c @@ -18,9 +18,8 @@ #include #include -#include "common/int.h" #include "utils/builtins.h" -#include "port/pg_bitutils.h" +#include "utils/numutils.h" /* * A table of all two-digit numbers. This is used to speed up decimal digit @@ -38,53 +37,6 @@ static const char DIGIT_TABLE[200] = "80" "81" "82" "83" "84" "85" "86" "87" "88" "89" "90" "91" "92" "93" "94" "95" "96" "97" "98" "99"; -/* - * Adapted from http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10 - */ -static inline int -decimalLength32(const uint32 v) -{ - int t; - static const uint32 PowersOfTen[] = { - 1, 10, 100, - 1000, 10000, 100000, - 1000000, 10000000, 100000000, - 1000000000 - }; - - /* - * Compute base-10 logarithm by dividing the base-2 logarithm by a - * good-enough approximation of the base-2 logarithm of 10 - */ - t = (pg_leftmost_one_pos32(v) + 1) * 1233 / 4096; - return t + (v >= PowersOfTen[t]); -} - -static inline int -decimalLength64(const uint64 v) -{ - int t; - static const uint64 PowersOfTen[] = { - UINT64CONST(1), UINT64CONST(10), - UINT64CONST(100), UINT64CONST(1000), - UINT64CONST(10000), UINT64CONST(100000), - UINT64CONST(1000000), UINT64CONST(10000000), - UINT64CONST(100000000), UINT64CONST(1000000000), - UINT64CONST(10000000000), UINT64CONST(100000000000), - UINT64CONST(1000000000000), UINT64CONST(10000000000000), - UINT64CONST(100000000000000), UINT64CONST(1000000000000000), - UINT64CONST(10000000000000000), UINT64CONST(100000000000000000), - UINT64CONST(1000000000000000000), UINT64CONST(10000000000000000000) - }; - - /* - * Compute base-10 logarithm by dividing the base-2 logarithm by a - * good-enough approximation of the base-2 logarithm of 10 - */ - t = (pg_leftmost_one_pos64(v) + 1) * 1233 / 4096; - return t + (v >= PowersOfTen[t]); -} - static const int8 hexlookup[128] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, diff --git a/src/include/utils/numutils.h b/src/include/utils/numutils.h new file mode 100644 index 0000000000..876e64f2df --- /dev/null +++ b/src/include/utils/numutils.h @@ -0,0 +1,67 @@ +/*------------------------------------------------------------------------- + * + * numutils.h + * Decimal length functions for numutils.c + * + * + * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/utils/numutils.h + * + *------------------------------------------------------------------------- + */ +#ifndef NUMUTILS_H +#define NUMUTILS_H + +#include "common/int.h" +#include "port/pg_bitutils.h" + +/* + * Adapted from http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10 + */ +static inline int +decimalLength32(const uint32 v) +{ + int t; + static const uint32 PowersOfTen[] = { + 1, 10, 100, + 1000, 10000, 100000, + 1000000, 10000000, 100000000, + 1000000000 + }; + + /* + * Compute base-10 logarithm by dividing the base-2 logarithm by a + * good-enough approximation of the base-2 logarithm of 10 + */ + t = (pg_leftmost_one_pos32(v) + 1) * 1233 / 4096; + return t + (v >= PowersOfTen[t]); +} + +static inline int +decimalLength64(const uint64 v) +{ + int t; + static const uint64 PowersOfTen[] = { + UINT64CONST(1), UINT64CONST(10), + UINT64CONST(100), UINT64CONST(1000), + UINT64CONST(10000), UINT64CONST(100000), + UINT64CONST(1000000), UINT64CONST(10000000), + UINT64CONST(100000000), UINT64CONST(1000000000), + UINT64CONST(10000000000), UINT64CONST(100000000000), + UINT64CONST(1000000000000), UINT64CONST(10000000000000), + UINT64CONST(100000000000000), UINT64CONST(1000000000000000), + UINT64CONST(10000000000000000), UINT64CONST(100000000000000000), + UINT64CONST(1000000000000000000), UINT64CONST(10000000000000000000) + }; + + /* + * Compute base-10 logarithm by dividing the base-2 logarithm by a + * good-enough approximation of the base-2 logarithm of 10 + */ + t = (pg_leftmost_one_pos64(v) + 1) * 1233 / 4096; + return t + (v >= PowersOfTen[t]); +} + +#endif /* NUMUTILS_H */ -- 2.32.0