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* Further tweaking of width_bucket() edge cases.Tom Lane2023-03-311-3/+14
| | | | | | | | | | | | | | | | | | I realized that the third overflow case I posited in commit b0e9e4d76 actually should be handled in a different way: rather than tolerating the idea that the quotient could round to 1, we should clamp so that the output cannot be more than "count" when we know that the operand is less than bound2. That being the case, we don't need an overflow-aware increment in that code path, which leads me to revert the movement of the pg_add_s32_overflow() call. (The diff in width_bucket_float8 might be easier to read by comparing against b0e9e4d76^.) What's more, width_bucket_numeric also has this problem of the quotient potentially rounding to 1, so add a clamp there too. As before, I'm not quite convinced that a back-patch is warranted. Discussion: https://postgr.es/m/391415.1680268470@sss.pgh.pa.us
* Allow underscores in integer and numeric constants.Dean Rasheed2023-02-041-23/+83
| | | | | | | | | | | | | | | | | | | This allows underscores to be used in integer and numeric literals, and their corresponding type input functions, for visual grouping. For example: 1_500_000_000 3.14159_26535_89793 0xffff_ffff 0b_1001_0001 A single underscore is allowed between any 2 digits, or immediately after the base prefix indicator of non-decimal integers, per SQL:202x draft. Peter Eisentraut and Dean Rasheed Discussion: https://postgr.es/m/84aae844-dc55-a4be-86d9-4f0fa405cc97%40enterprisedb.com
* Make int64_div_fast_to_numeric() more robust.Dean Rasheed2023-02-031-27/+46
| | | | | | | | | | | | | | | | | | The prior coding of int64_div_fast_to_numeric() had a number of bugs that would cause it to fail under different circumstances, such as with log10val2 <= 0, or log10val2 a multiple of 4, or in the "slow" numeric path with log10val2 >= 10. None of those could be triggered by any of our current code, which only uses log10val2 = 3 or 6. However, they made it a hazard for any future code that might use it. Also, since this is exported by numeric.c, users writing their own C code might choose to use it. Therefore fix, and back-patch to v14, where it was introduced. Dean Rasheed, reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCW8gXgW0tgPxPgHDPhVX71%2BSWFRkhnXy%2BTfGDsKLepu2g%40mail.gmail.com
* Clarify the choice of rscale in numeric_sqrt().Dean Rasheed2023-02-021-2/+15
| | | | | | | | | | | | | Improve the comment explaining the choice of rscale in numeric_sqrt(), and ensure that the code works consistently when other values of NBASE/DEC_DIGITS are used. Note that, in practice, we always expect DEC_DIGITS == 4, and this does not change the computation in that case. Joel Jacobson and Dean Rasheed Discussion: https://postgr.es/m/06712c29-98e9-43b3-98da-f234d81c6e49%40app.fastmail.com
* Ensure that numeric.c compiles with other NBASE values.Dean Rasheed2023-02-021-0/+8
| | | | | | | | | | As noted in the comments, support for different NBASE values is really only of historical interest, but as long as we're keeping it, we might as well make sure that it compiles. Joel Jacobson Discussion: https://postgr.es/m/06712c29-98e9-43b3-98da-f234d81c6e49%40app.fastmail.com
* Add non-decimal integer support to type numeric.Dean Rasheed2023-01-231-61/+299
| | | | | | | | | | | | | | | | | | This enhances the numeric type input function, adding support for hexadecimal, octal, and binary integers of any size, up to the limits of the numeric type. Since 6fcda9aba8, such non-decimal integers have been accepted by the parser as integer literals and passed through to numeric_in(). This commit gives numeric_in() the ability to handle them. While at it, simplify the handling of NaN and infinities, reducing the number of calls to pg_strncasecmp(), and arrange for pg_strncasecmp() to not be called at all for regular numbers. This gives a significant performance improvement for decimal inputs, more than offsetting the small performance hit of checking for non-decimal input. Discussion: https://postgr.es/m/CAEZATCV8XShnmT9HZy25C%2Bo78CVOFmUN5EM9FRAZ5xvYTggPMg%40mail.gmail.com
* Optimise numeric division for 3 and 4 base-NBASE digit divisors.Dean Rasheed2023-01-231-0/+167
| | | | | | | | | | | | | | | | | On platforms with 128-bit integer support, introduce a new function div_var_int64(), along the same lines as div_var_int() added in d1b307eef2 for divisors with 1 or 2 base-NBASE digits, and use it to speed up div_var() and div_var_fast() in a similar way when the divisor has 3 or 4 base-NBASE digits. This gives significant performance gains for divisors with 9-16 decimal digits. Joel Jacobson. Discussion: https://postgr.es/m/b7a5893d-af18-4c0b-8918-96de5f1bbf39%40app.fastmail.com https://postgr.es/m/CAEZATCXGm%3DDyTq%3DFrcOqC0gPMVveKUYTaD5KRRoajrUTiWxVMw%40mail.gmail.com
* Update copyright for 2023Bruce Momjian2023-01-021-1/+1
| | | | Backpatch-through: 11
* Static assertions cleanupPeter Eisentraut2022-12-151-1/+2
| | | | | | | | | | | | | | | | | | | | | Because we added StaticAssertStmt() first before StaticAssertDecl(), some uses as well as the instructions in c.h are now a bit backwards from the "native" way static assertions are meant to be used in C. This updates the guidance and moves some static assertions to better places. Specifically, since the addition of StaticAssertDecl(), we can put static assertions at the file level. This moves a number of static assertions out of function bodies, where they might have been stuck out of necessity, to perhaps better places at the file level or in header files. Also, when the static assertion appears in a position where a declaration is allowed, then using StaticAssertDecl() is more native than StaticAssertStmt(). Reviewed-by: John Naylor <john.naylor@enterprisedb.com> Discussion: https://www.postgresql.org/message-id/flat/941a04e7-dd6f-c0e4-8cdf-a33b3338cbda%40enterprisedb.com
* Convert a few datatype input functions to use "soft" error reporting.Tom Lane2022-12-091-35/+63
| | | | | | | | | | | | | | | This patch converts the input functions for bool, int2, int4, int8, float4, float8, numeric, and contrib/cube to the new soft-error style. array_in and record_in are also converted. There's lots more to do, but this is enough to provide proof-of-concept that the soft-error API is usable, as well as reference examples for how to convert input functions. This patch is mostly by me, but it owes very substantial debt to earlier work by Nikita Glukhov, Andrew Dunstan, and Amul Sul. Thanks to Andres Freund for review. Discussion: https://postgr.es/m/3bbbb0df-7382-bf87-9737-340ba096e034@postgrespro.ru
* Improve the accuracy of numeric power() for integer exponents.Dean Rasheed2022-10-201-43/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | This makes the choice of result scale of numeric power() for integer exponents consistent with the choice for non-integer exponents, and with the result scale of other numeric functions. Specifically, the result scale will be at least as large as the scale of either input, and sufficient to ensure that the result has at least 16 significant digits. Formerly, the result scale was based only on the scale of the first input, without taking into account the weight of the result. For results with negative weight, that could lead to results with very few or even no non-zero significant digits (e.g., 10.0 ^ (-18) produced 0.0000000000000000). Fix this by moving responsibility for the choice of result scale into power_var_int(), which already has code to estimate the result weight. Per report by Adrian Klaver and suggested fix by Tom Lane. No back-patch -- arguably this is a bug fix, but one which is easy to work around, so it doesn't seem worth the risk of changing query results in stable branches. Discussion: https://postgr.es/m/12a40226-70ac-3a3b-3d3a-fdaf9e32d312%40aklaver.com
* Remove unnecessary uses of Abs()Peter Eisentraut2022-10-071-10/+10
| | | | | | | | Use C standard abs() or fabs() instead. Reviewed-by: Zhang Mingli <zmlpostgres@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/4beb42b5-216b-bce8-d452-d924d5794c63%40enterprisedb.com
* Harmonize more parameter names in bulk.Peter Geoghegan2022-09-201-3/+3
| | | | | | | | | | | | | | | | Make sure that function declarations use names that exactly match the corresponding names from function definitions in optimizer, parser, utility, libpq, and "commands" code, as well as in remaining library code. Do the same for all code related to frontend programs (with the exception of pg_dump/pg_dumpall related code). Like other recent commits that cleaned up function parameter names, this commit was written with help from clang-tidy. Later commits will handle ecpg and pg_dump/pg_dumpall. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
* Pre-beta mechanical code beautification.Tom Lane2022-05-121-108/+107
| | | | | Run pgindent, pgperltidy, and reformat-dat-files. I manually fixed a couple of comments that pgindent uglified.
* Clean up assorted failures under clang's -fsanitize=undefined checks.Tom Lane2022-03-031-0/+8
| | | | | | | | | | | | | | | | | | | | | | Most of these are cases where we could call memcpy() or other libc functions with a NULL pointer and a zero count, which is forbidden by POSIX even though every production version of libc allows it. We've fixed such things before in a piecemeal way, but apparently never made an effort to try to get them all. I don't claim that this patch does so either, but it gets every failure I observe in check-world, using clang 12.0.1 on current RHEL8. numeric.c has a different issue that the sanitizer doesn't like: "ln(-1.0)" will compute log10(0) and then try to assign the resulting -Inf to an integer variable. We don't actually use the result in such a case, so there's no live bug. Back-patch to all supported branches, with the idea that we might start running a buildfarm member that tests this case. This includes back-patching c1132aae3 (Check the size in COPY_POINTER_FIELD), which previously silenced some of these issues in copyfuncs.c. Discussion: https://postgr.es/m/CALNJ-vT9r0DSsAOw9OXVJFxLENoVS_68kJ5x0p44atoYH+H4dg@mail.gmail.com
* Optimise numeric division for one and two base-NBASE digit divisors.Dean Rasheed2022-02-271-43/+180
| | | | | | | | | | | | | | | | | | | | | | | | Formerly div_var() had "fast path" short division code that was significantly faster when the divisor was just one base-NBASE digit, but otherwise used long division. This commit adds a new function div_var_int() that divides by an arbitrary 32-bit integer, using the fast short division algorithm, and updates both div_var() and div_var_fast() to use it for one and two digit divisors. In the case of div_var(), this is slightly faster in the one-digit case, because it avoids some digit array copying, and is much faster in the two-digit case where it replaces long division. For div_var_fast(), it is much faster in both cases because the main div_var_fast() algorithm is optimised for larger inputs. Additionally, optimise exp() and ln() by using div_var_int(), allowing a NumericVar to be replaced by an int in a couple of places, most notably in the Taylor series code. This produces a significant speedup of exp(), ln() and the numeric_big regression test. Dean Rasheed, reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCVwsBi-ND-t82Cuuh1=8ee6jdOpzsmGN+CUZB6yjLg9jw@mail.gmail.com
* Simplify the inner loop of numeric division in div_var().Dean Rasheed2022-02-271-21/+15
| | | | | | | | | | | | | | In the standard numeric division algorithm, the inner loop multiplies the divisor by the next quotient digit and subtracts that from the working dividend. As suggested by the original code comment, the separate "carry" and "borrow" variables (from the multiplication and subtraction steps respectively) can be folded together into a single variable. Doing so significantly improves performance, as well as simplifying the code. Dean Rasheed, reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCVwsBi-ND-t82Cuuh1=8ee6jdOpzsmGN+CUZB6yjLg9jw@mail.gmail.com
* Apply auto-vectorization to the inner loop of div_var_fast().Dean Rasheed2022-02-271-2/+11
| | | | | | | | | | | | | | | | | | | | | This loop is basically the same as the inner loop of mul_var(), which was auto-vectorized in commit 8870917623, but the compiler will only consider auto-vectorizing the div_var_fast() loop if the assignment target div[qi + i] is replaced by div_qi[i], where div_qi = &div[qi]. Additionally, since the compiler doesn't know that qdigit is guaranteed to fit in a 16-bit NumericDigit, cast it to NumericDigit before multiplying to make the resulting auto-vectorized code more efficient (avoiding unnecessary multiplication of the high 16 bits). While at it, per suggestion from Tom Lane, change var1digit in mul_var() to be a NumericDigit rather than an int for the same reason. This actually makes no difference with modern gcc, but it might help other compilers generate more efficient assembly. Dean Rasheed, reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCVwsBi-ND-t82Cuuh1=8ee6jdOpzsmGN+CUZB6yjLg9jw@mail.gmail.com
* Update copyright for 2022Bruce Momjian2022-01-071-1/+1
| | | | Backpatch-through: 10
* Remove unused includesPeter Eisentraut2021-12-011-1/+0
| | | | | | | These haven't been needed for a long time. Reviewed-by: John Naylor <john.naylor@enterprisedb.com> Discussion: https://www.postgresql.org/message-id/flat/b239564c-cad0-b23e-c57e-166d883cb97d@enterprisedb.com
* Fix corner-case loss of precision in numeric_power().Dean Rasheed2021-10-061-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | This fixes a loss of precision that occurs when the first input is very close to 1, so that its logarithm is very small. Formerly, during the initial low-precision calculation to estimate the result weight, the logarithm was computed to a local rscale that was capped to NUMERIC_MAX_DISPLAY_SCALE (1000). However, the base may be as close as 1e-16383 to 1, hence its logarithm may be as small as 1e-16383, and so the local rscale needs to be allowed to exceed 16383, otherwise all precision is lost, leading to a poor choice of rscale for the full-precision calculation. Fix this by removing the cap on the local rscale during the initial low-precision calculation, as we already do in the full-precision calculation. This doesn't change the fact that the initial calculation is a low-precision approximation, computing the logarithm to around 8 significant digits, which is very fast, especially when the base is very close to 1. Patch by me, reviewed by Alvaro Herrera. Discussion: https://postgr.es/m/CAEZATCV-Ceu%2BHpRMf416yUe4KKFv%3DtdgXQAe5-7S9tD%3D5E-T1g%40mail.gmail.com
* Adjust the integer overflow tests in the numeric code.Dean Rasheed2021-08-061-12/+10
| | | | | | | | | | | | | | | | | | | | Formerly, the numeric code tested whether an integer value of a larger type would fit in a smaller type by casting it to the smaller type and then testing if the reverse conversion produced the original value. That's perfectly fine, except that it caused a test failure on buildfarm animal castoroides, most likely due to a compiler bug. Instead, do these tests by comparing against PG_INT16/32_MIN/MAX. That matches existing code in other places, such as int84(), which is more widely tested, and so is less likely to go wrong. While at it, add regression tests covering the numeric-to-int8/4/2 conversions, and adjust the recently added tests to the style of 434ddfb79a (on the v11 branch) to make failures easier to diagnose. Per buildfarm via Tom Lane, reviewed by Tom Lane. Discussion: https://postgr.es/m/2394813.1628179479%40sss.pgh.pa.us
* Fix division-by-zero error in to_char() with 'EEEE' format.Dean Rasheed2021-08-051-29/+37
| | | | | | | | | | | | | | | | | | | | This fixes a long-standing bug when using to_char() to format a numeric value in scientific notation -- if the value's exponent is less than -NUMERIC_MAX_DISPLAY_SCALE-1 (-1001), it produced a division-by-zero error. The reason for this error was that get_str_from_var_sci() divides its input by 10^exp, which it produced using power_var_int(). However, the underflow test in power_var_int() causes it to return zero if the result scale is too small. That's not a problem for power_var_int()'s only other caller, power_var(), since that limits the rscale to 1000, but in get_str_from_var_sci() the exponent can be much smaller, requiring a much larger rscale. Fix by introducing a new function to compute 10^exp directly, with no rscale limit. This also allows 10^exp to be computed more efficiently, without any numeric multiplication, division or rounding. Discussion: https://postgr.es/m/CAEZATCWhojfH4whaqgUKBe8D5jNHB8ytzemL-PnRx+KCTyMXmg@mail.gmail.com
* Fix corner-case errors and loss of precision in numeric_power().Dean Rasheed2021-07-311-15/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes a couple of related problems that arise when raising numbers to very large powers. Firstly, when raising a negative number to a very large integer power, the result should be well-defined, but the previous code would only cope if the exponent was small enough to go through power_var_int(). Otherwise it would throw an internal error, attempting to take the logarithm of a negative number. Fix this by adding suitable handling to the general case in power_var() to cope with negative bases, checking for integer powers there. Next, when raising a (positive or negative) number whose absolute value is slightly less than 1 to a very large power, the result should approach zero as the power is increased. However, in some cases, for sufficiently large powers, this would lose all precision and return 1 instead of 0. This was due to the way that the local_rscale was being calculated for the final full-precision calculation: local_rscale = rscale + (int) val - ln_dweight + 8 The first two terms on the right hand side are meant to give the number of significant digits required in the result ("val" being the estimated result weight). However, this failed to account for the fact that rscale is clipped to a maximum of NUMERIC_MAX_DISPLAY_SCALE (1000), and the result weight might be less then -1000, causing their sum to be negative, leading to a loss of precision. Fix this by forcing the number of significant digits calculated to be nonnegative. It's OK for it to be zero (when the result weight is less than -1000), since the local_rscale value then includes a few extra digits to ensure an accurate result. Finally, add additional underflow checks to exp_var() and power_var(), so that they consistently return zero for cases like this where the result is indistinguishable from zero. Some paths through this code already returned zero in such cases, but others were throwing overflow errors. Dean Rasheed, reviewed by Yugo Nagata. Discussion: http://postgr.es/m/CAEZATCW6Dvq7+3wN3tt5jLj-FyOcUgT5xNoOqce5=6Su0bCR0w@mail.gmail.com
* Allow numeric scale to be negative or greater than precision.Dean Rasheed2021-07-261-35/+95
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Formerly, when specifying NUMERIC(precision, scale), the scale had to be in the range [0, precision], which was per SQL spec. This commit extends the range of allowed scales to [-1000, 1000], independent of the precision (whose valid range remains [1, 1000]). A negative scale implies rounding before the decimal point. For example, a column might be declared with a scale of -3 to round values to the nearest thousand. Note that the display scale remains non-negative, so in this case the display scale will be zero, and all digits before the decimal point will be displayed. A scale greater than the precision supports fractional values with zeros immediately after the decimal point. Take the opportunity to tidy up the code that packs, unpacks and validates the contents of a typmod integer, encapsulating it in a small set of new inline functions. Bump the catversion because the allowed contents of atttypmod have changed for numeric columns. This isn't a change that requires a re-initdb, but negative scale values in the typmod would confuse old backends. Dean Rasheed, with additional improvements by Tom Lane. Reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCWdNLgpKihmURF8nfofP0RFtAKJ7ktY6GcZOPnMfUoRqA@mail.gmail.com
* Fix numeric_mul() overflow due to too many digits after decimal point.Dean Rasheed2021-07-101-1/+9
| | | | | | | | | This fixes an overflow error when using the numeric * operator if the result has more than 16383 digits after the decimal point by rounding the result. Overflow errors should only occur if the result has too many digits *before* the decimal point. Discussion: https://postgr.es/m/CAEZATCUmeFWCrq2dNzZpRj5+6LfN85jYiDoqm+ucSXhb9U2TbA@mail.gmail.com
* Prevent numeric overflows in parallel numeric aggregates.Dean Rasheed2021-07-051-138/+117
| | | | | | | | | | | | | | | | | | | | | | | | | Formerly various numeric aggregate functions supported parallel aggregation by having each worker convert partial aggregate values to Numeric and use numeric_send() as part of serializing their state. That's problematic, since the range of Numeric is smaller than that of NumericVar, so it's possible for it to overflow (on either side of the decimal point) in cases that would succeed in non-parallel mode. Fix by serializing NumericVars instead, to avoid the overflow risk and ensure that parallel and non-parallel modes work the same. A side benefit is that this improves the efficiency of the serialization/deserialization code, which can make a noticeable difference to performance with large numbers of parallel workers. No back-patch due to risk from changing the binary format of the aggregate serialization states, as well as lack of prior field complaints and low probability of such overflows in practice. Patch by me. Thanks to David Rowley for review and performance testing, and Ranier Vilela for an additional suggestion. Discussion: https://postgr.es/m/CAEZATCUmeFWCrq2dNzZpRj5+6LfN85jYiDoqm+ucSXhb9U2TbA@mail.gmail.com
* Error message refactoringPeter Eisentraut2021-06-271-8/+8
| | | | | | Take some untranslatable things out of the message and replace by format placeholders, to reduce translatable strings and reduce translation mistakes.
* Change return type of EXTRACT to numericPeter Eisentraut2021-04-061-0/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The previous implementation of EXTRACT mapped internally to date_part(), which returned type double precision (since it was implemented long before the numeric type existed). This can lead to imprecise output in some cases, so returning numeric would be preferrable. Changing the return type of an existing function is a bit risky, so instead we do the following: We implement a new set of functions, which are now called "extract", in parallel to the existing date_part functions. They work the same way internally but use numeric instead of float8. The EXTRACT construct is now mapped by the parser to these new extract functions. That way, dumps of views etc. from old versions (which would use date_part) continue to work unchanged, but new uses will map to the new extract functions. Additionally, the reverse compilation of EXTRACT now reproduces the original syntax, using the new mechanism introduced in 40c24bfef92530bd846e111c1742c2a54441c62c. The following minor changes of behavior result from the new implementation: - The column name from an isolated EXTRACT call is now "extract" instead of "date_part". - Extract from date now rejects inappropriate field names such as HOUR. It was previously mapped internally to extract from timestamp, so it would silently accept everything appropriate for timestamp. - Return values when extracting fields with possibly fractional values, such as second and epoch, now have the full scale that the value has internally (so, for example, '1.000000' instead of just '1'). Reported-by: Petr Fedorov <petr.fedorov@phystech.edu> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/42b73d2d-da12-ba9f-570a-420e0cce19d9@phystech.edu
* Add an explicit cast to double when using fabs().Dean Rasheed2021-01-051-1/+1
| | | | | | | Commit bc43b7c2c0 used fabs() directly on an int variable, which apparently requires an explicit cast on some platforms. Per buildfarm.
* Fix numeric_power() when the exponent is INT_MIN.Dean Rasheed2021-01-051-1/+1
| | | | | | | | | | | | In power_var_int(), the computation of the number of significant digits to use in the computation used log(Abs(exp)), which isn't safe because Abs(exp) returns INT_MIN when exp is INT_MIN. Use fabs() instead of Abs(), so that the exponent is cast to a double before the absolute value is taken. Back-patch to 9.6, where this was introduced (by 7d9a4737c2). Discussion: https://postgr.es/m/CAEZATCVd6pMkz=BrZEgBKyqqJrt2xghr=fNc8+Z=5xC6cgWrWA@mail.gmail.com
* Update copyright for 2021Bruce Momjian2021-01-021-1/+1
| | | | Backpatch-through: 9.5
* Avoid gratuitous inaccuracy in numeric width_bucket().Tom Lane2020-10-081-15/+16
| | | | | | | | | | | | | | | | | | Multiply before dividing, not the reverse, so that cases that should produce exact results do produce exact results. (width_bucket_float8 got this right already.) Even when the result is inexact, this avoids making it more inexact, since only the division step introduces any imprecision. While at it, fix compute_bucket() to not uselessly repeat the sign check already done by its caller, and avoid duplicating the multiply/divide steps by adjusting variable usage. Per complaint from Martin Visser. Although this seems like a bug fix, I'm hesitant to risk changing width_bucket()'s results in stable branches, so no back-patch. Discussion: https://postgr.es/m/6FA5117D-6AED-4656-8FEF-B74AC18FAD85@brytlyt.com
* Fix numeric width_bucket() to allow its first argument to be infinite.Tom Lane2020-10-081-2/+3
| | | | | | | | | | | | | | While the calculation is not well-defined if the bounds arguments are infinite, there is a perfectly sane outcome if the test operand is infinite: it's just like any other value that's before the first bucket or after the last one. width_bucket_float8() got this right, but I was too hasty about the case when adding infinities to numerics (commit a57d312a7), so that width_bucket_numeric() just rejected it. Fix that, and sync the relevant error message strings. No back-patch needed, since infinities-in-numeric haven't shipped yet. Discussion: https://postgr.es/m/2465409.1602170063@sss.pgh.pa.us
* Expose internal function for converting int64 to numericPeter Eisentraut2020-09-091-87/+29
| | | | | | | | Existing callers had to take complicated detours via DirectFunctionCall1(). This simplifies a lot of code. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://www.postgresql.org/message-id/flat/42b73d2d-da12-ba9f-570a-420e0cce19d9@phystech.edu
* Use plain memset() in numeric.c, not MemSet and friends.Tom Lane2020-09-081-1/+1
| | | | | | | | | | | | | | | | | | | | This essentially reverts a micro-optimization I made years ago, as part of the much larger commit d72f6c750. It's doubtful that there was any hard evidence for it being helpful even then, and the case is even more dubious now that modern compilers are so much smarter about inlining memset(). The proximate reason for undoing it is to get rid of the type punning inherent in MemSet, for fear that that may cause problems now that we're applying additional optimization switches to numeric.c. At the very least this'll silence some warnings from a few old buildfarm animals. (It's probably past time for another look at whether MemSet is still worth anything at all, but I do not propose to tackle that question right now.) Discussion: https://postgr.es/m/CAJ3gD9evtA_vBo+WMYMyT-u=keHX7-r8p2w7OSRfXf42LTwCZQ@mail.gmail.com
* Frob numeric.c loop so that clang will auto-vectorize it too.Tom Lane2020-09-071-6/+8
| | | | | | | | | | Experimentation shows that clang will auto-vectorize the critical multiplication loop if the termination condition is written "i2 < limit" rather than "i2 <= limit". This seems unbelievably stupid, but I've reproduced it on both clang 9.0.1 (RHEL8) and 11.0.3 (macOS Catalina). gcc doesn't care, so tweak the code to do it that way. Discussion: https://postgr.es/m/CAJ3gD9evtA_vBo+WMYMyT-u=keHX7-r8p2w7OSRfXf42LTwCZQ@mail.gmail.com
* Apply auto-vectorization to the inner loop of numeric multiplication.Tom Lane2020-09-061-3/+12
| | | | | | | | | | | | | | | | | | | | | | | Compile numeric.c with -ftree-vectorize where available, and adjust the innermost loop of mul_var() so that it is amenable to being auto-vectorized. (Mainly, that involves making it process the arrays left-to-right not right-to-left.) Applying -ftree-vectorize actually makes numeric.o smaller, at least with my compiler (gcc 8.3.1 on x86_64), and it's a little faster too. Independently of that, fixing the inner loop to be vectorizable also makes things a bit faster. But doing both is a huge win for multiplications with lots of digits. For me, the numeric regression test is the same speed to within measurement noise, but numeric_big is a full 45% faster. We also looked into applying -funroll-loops, but that makes numeric.o bloat quite a bit, and the additional speed improvement is very marginal. Amit Khandekar, reviewed and edited a little by me Discussion: https://postgr.es/m/CAJ3gD9evtA_vBo+WMYMyT-u=keHX7-r8p2w7OSRfXf42LTwCZQ@mail.gmail.com
* Support infinity and -infinity in the numeric data type.Tom Lane2020-07-221-305/+1169
| | | | | | | | | | | | | | | Add infinities that behave the same as they do in the floating-point data types. Aside from any intrinsic usefulness these may have, this closes an important gap in our ability to convert floating values to numeric and/or replace float-based APIs with numeric. The new values are represented by bit patterns that were formerly not used (although old code probably would take them for NaNs). So there shouldn't be any pg_upgrade hazard. Patch by me, reviewed by Dean Rasheed and Andrew Gierth Discussion: https://postgr.es/m/606717.1591924582@sss.pgh.pa.us
* Add +(pg_lsn,numeric) and -(pg_lsn,numeric) operators.Fujii Masao2020-06-301-0/+98
| | | | | | | | | | | By using these operators, the number of bytes can be added into and subtracted from LSN. Bump catalog version. Author: Fujii Masao Reviewed-by: Kyotaro Horiguchi, Michael Paquier, Asif Rehman Discussion: https://postgr.es/m/ed9f7f74-e996-67f8-554a-52ebd3779b3b@oss.nttdata.com
* Disallow factorial of negative numbersPeter Eisentraut2020-06-181-0/+4
| | | | | | | The previous implementation returned 1 for all negative numbers, which is not sensible under any definition. Discussion: https://www.postgresql.org/message-id/flat/6ce1df0e-86a3-e544-743a-f357ff663f68%402ndquadrant.com
* Sync behavior of var_samp and stddev_samp for single NaN inputs.Tom Lane2020-06-131-18/+17
| | | | | | | | | | | | | | | | | | | | var_samp(numeric) and stddev_samp(numeric) disagreed with their float cousins about what to do for a single non-null input value that is NaN. The float versions return NULL on the grounds that the calculation is only defined for more than one non-null input, which seems like the right answer. But the numeric versions returned NaN, as a result of dealing with edge cases in the wrong order. Fix that. The patch also gets rid of an insignificant memory leak in such cases. This inconsistency is of long standing, but on the whole it seems best not to back-patch the change into stable branches; nobody's complained and it's such an obscure point that nobody's likely to complain. (Note that v13 and v12 now contain test cases that will notice if we accidentally back-patch this behavior change in future.) Report and patch by me; thanks to Dean Rasheed for review. Discussion: https://postgr.es/m/353062.1591898766@sss.pgh.pa.us
* Fix mishandling of NaN counts in numeric_[avg_]combine.Tom Lane2020-06-111-6/+6
| | | | | | | | | | | | | | | | | | | | | | When merging two NumericAggStates, the code missed adding the new state's NaNcount unless its N was also nonzero; since those counts are independent, this is wrong. This would only have visible effect if some partial aggregate scans found only NaNs while earlier ones found only non-NaNs; then we could end up falsely deciding that there were no NaNs and fail to return a NaN final result as expected. That's pretty improbable, so it's no surprise this hasn't been reported from the field. Still, it's a bug. I didn't try to produce a regression test that would show the bug, but I did notice that these functions weren't being reached at all in our regression tests, so I improved the tests to at least exercise them. With these additions, I see pretty complete code coverage on the aggregation-related functions in numeric.c. Back-patch to 9.6 where this code was introduced. (I only added the improved test case as far back as v10, though, since the relevant part of aggregates.sql isn't there at all in 9.6.)
* Run pgindent with new pg_bsd_indent version 2.1.1.Tom Lane2020-05-161-1/+1
| | | | | | | | | | | Thomas Munro fixed a longstanding annoyance in pg_bsd_indent, that it would misformat lines containing IsA() macros on the assumption that the IsA() call should be treated like a cast. This improves some other cases involving field/variable names that match typedefs, too. The only places that get worse are a couple of uses of the OpenSSL macro STACK_OF(); we'll gladly take that trade-off. Discussion: https://postgr.es/m/20200114221814.GA19630@alvherre.pgsql
* Improve the performance and accuracy of numeric sqrt() and ln().Dean Rasheed2020-03-281-49/+536
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of using Newton's method to compute numeric square roots, use the Karatsuba square root algorithm, which performs better for numbers of all sizes. In practice, this is 3-5 times faster for inputs with just a few digits and up to around 10 times faster for larger inputs. Also, the new algorithm guarantees that the final digit of the result is correctly rounded, since it computes an integer square root with truncation, containing at least 1 extra decimal digit before rounding. The former algorithm would occasionally round the wrong way because it rounded both the intermediate and final results. In addition, arrange for sqrt_var() to explicitly support negative rscale values (rounding before the decimal point). This allows the argument reduction phase of ln_var() to be optimised for large inputs, since it only needs to compute square roots with a few more digits than the final ln() result, rather than computing all the digits before the decimal point. For very large inputs, this can be many thousands of times faster. In passing, optimise div_var_fast() in a couple of places where it was doing unnecessary work. Patch be me, reviewed by Tom Lane and Tels. Discussion: https://postgr.es/m/CAEZATCV1A7+jD3P30Zu31KjaxeSEyOn3v9d6tYegpxcq3cQu-g@mail.gmail.com
* Fix corner-case loss of precision in numeric ln().Dean Rasheed2020-03-011-1/+9
| | | | | | | | | | | | | | | | | | | | | | When deciding on the local rscale to use for the Taylor series expansion, ln_var() neglected to account for the fact that the result is subsequently multiplied by a factor of 2^(nsqrt+1), where nsqrt is the number of square root operations performed in the range reduction step, which can be as high as 22 for very large inputs. This could result in a loss of precision, particularly when combined with large rscale values, for which a large number of Taylor series terms is required (up to around 400). Fix by computing a few extra digits in the Taylor series, based on the weight of the multiplicative factor log10(2^(nsqrt+1)). It remains to be proven whether or not the other 8 extra digits used for the Taylor series is appropriate, but this at least deals with the obvious oversight of failing to account for the effects of the final multiplication. Per report from Justin AnyhowStep. Reviewed by Tom Lane. Discussion: https://postgr.es/m/16280-279f299d9c06e56f@postgresql.org
* Move src/backend/utils/hash/hashfn.c to src/commonRobert Haas2020-02-271-1/+1
| | | | | | | | | | | | | | This also involves renaming src/include/utils/hashutils.h, which becomes src/include/common/hashfn.h. Perhaps an argument can be made for keeping the hashutils.h name, but it seemed more consistent to make it match the name of the file, and also more descriptive of what is actually going on here. Patch by me, reviewed by Suraj Kharage and Mark Dilger. Off-list advice on how not to break the Windows build from Davinder Singh and Amit Kapila. Discussion: http://postgr.es/m/CA+TgmoaRiG4TXND8QuM6JXFRkM_1wL2ZNhzaUKsuec9-4yrkgw@mail.gmail.com
* Add functions gcd() and lcm() for integer and numeric types.Dean Rasheed2020-01-251-0/+171
| | | | | | | | | These compute the greatest common divisor and least common multiple of a pair of numbers using the Euclidean algorithm. Vik Fearing, reviewed by Fabien Coelho. Discussion: https://postgr.es/m/adbd3e0b-e3f1-5bbc-21db-03caf1cef0f7@2ndquadrant.com
* Add functions min_scale(numeric) and trim_scale(numeric).Tom Lane2020-01-061-0/+91
| | | | | | | | | These allow better control of trailing zeroes in numeric values. Pavel Stehule, based on an old proposal of Marko Tiikkaja's; review by Karl Pinc Discussion: https://postgr.es/m/CAFj8pRDjs-navGASeF0Wk74N36YGFJ+v=Ok9_knRa7vDc-qugg@mail.gmail.com
* Update copyrights for 2020Bruce Momjian2020-01-011-1/+1
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4