In addition to the example that was added in 203b80ab, mention these
special cases in the doc comment. This change also adjusts the example
to include "+Inf", as it was not otherwise mentioned that the plus
symbol may be present.
Fix#30990
Change-Id: I97d66f4aff6a17a6ccc0ee2e7f32e39ae91ae454
Reviewed-on: https://go-review.googlesource.com/c/go/+/179738
Reviewed-by: Alex Miasoedov <msoedov@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Float formatting uses a multiprecision fallback path where Grisu3
algorithm fails. This has a bug during the rounding phase: the
difference between the decimal value and the upper bound is examined
byte-by-byte and doesn't properly handle the case where the first
divergence has a difference of 1.
For instance (using an example from #29491), for the number
498484681984085570, roundShortest examines the three decimal values:
lower: 498484681984085536
d: 498484681984085568
upper: 498484681984085600
After examining the 16th digit, we know that rounding d up will fall
within the bounds unless all remaining digits of d are 9 and all
remaining digits of upper are 0:
d: ...855xx
upper: ...856xx
However, the loop forgets that d and upper have already diverged and
then on the next iteration sees that the 17th digit of d is actually
lower than the 17th digit of upper and decides that we still can't round
up:
d: ...8556x
upper: ...8560x
Thus the original value is incorrectly rounded down to
498484681984085560 instead of the closer (and equally short)
498484681984085570.
Thanks to Brian Kessler for diagnosing this bug.
Fix it by remembering when we've seen divergence in previous digits.
This CL also fixes another bug in the same loop: for some inputs, the
decimal value d or the lower bound may have fewer digits than the upper
bound, yet the iteration through the digits starts at i=0 for each of
them. For instance, given the float64 value 1e23, we have
d: 99999999999999991611392
upper: 100000000000000000000000
but the loop starts by comparing '9' to '1' rather than '0' to '1'.
I haven't found any cases where this second bug causes incorrect output
because when the digit comparison fails on the first loop iteration the
upper bound always has more nonzero digits (i.e., the expression
'i+1 < upper.nd' is always true).
Fixes#29491
Change-Id: I58856a7a2e47935ec2f233d9f717ef15c78bb2d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/157697
Run-TryBot: Caleb Spare <cespare@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rémy Oudompheng <remyoudompheng@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This does *not* update the vendored tables.
A commit updating these tables should follow soon,
Mostly generated running UNICODE_VERSION=11.0.0 in x/text.
Manually updated next.txt file.
Updates golang/go#27945.
Change-Id: I939a01e235aeca898ee9afc99a531e7ad8444e12
Reviewed-on: https://go-review.googlesource.com/c/go/+/154420
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The byte-at-a-time allocation done quoting strings in appendQuotedWith
grows the output incrementally, which is poor behavior for very large
strings. An easy fix is to make sure the buffer has enough room at
least for an unquoted string.
Add a benchmark with a megabyte of non-ASCII data.
Before: 39 allocations.
After: 7 allocations.
We could do better by doing a lot more work but this seems like a big
result for little effort.
Fixes#31472.
Change-Id: I852139e0a2bd13722c4dd329ded8ae1759abad5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/172677
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Comparing errors using DeepEqual breaks if frame information
is added as proposed in Issue #29934.
Updates #29934.
Change-Id: I0372883288f974998138f95f6c7c79a60f922a3e
Reviewed-on: https://go-review.googlesource.com/c/162177
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
This CL modifies ParseInt and ParseUint to recognize
0b and 0o as binary and octal base prefixes when base == 0.
See golang.org/design/19308-number-literals for background.
For #19308.
For #12711.
Change-Id: I8efe067f415aa517bdefbff7e230d3fa1694d530
Reviewed-on: https://go-review.googlesource.com/c/160244
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
This CL modifies ParseInt, ParseUint, and ParseFloat
to accept digit-separating underscores in their arguments.
For ParseInt and ParseUint, the underscores are only
allowed when base == 0.
See golang.org/design/19308-number-literals for background.
For #28493.
Change-Id: I057ca2539d89314643f591ba8144c3ea7126651c
Reviewed-on: https://go-review.googlesource.com/c/160243
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This CL updates FormatFloat to format
standard hexadecimal floating-point constants,
using the 'x' and 'X' verbs.
See golang.org/design/19308-number-literals for background.
For #29008.
Change-Id: I540b8f71d492cfdb7c58af533d357a564591f28b
Reviewed-on: https://go-review.googlesource.com/c/160242
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This CL updates ParseFloat to recognize
standard hexadecimal floating-point constants.
See golang.org/design/19308-number-literals for background.
For #29008.
Change-Id: I45f3b0c36b5d92c0e8a4b35c05443a83d7a6d4b3
Reviewed-on: https://go-review.googlesource.com/c/160241
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The compiler can generate better code for shifts bounded to be less than 32
and thereby known to be less than any register width.
See https://golang.org/cl/109776.
Change-Id: I0c4c9f0faafa065fce3c10fd328830deb92f9e38
Reviewed-on: https://go-review.googlesource.com/c/111735
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Change-Id: Ie5b2ef0087dbc7b8191de8c8b4190396631e3c7f
Reviewed-on: https://go-review.googlesource.com/c/137215
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Fix the wording in "strconv" and "fmt" to make explicit
that the "g" and "G" formats remove trailing zeroes.
Fixes#25082
Change-Id: I2e2ad0a98d2ea27a3a8a006a0563b366f7a3b71b
Reviewed-on: https://go-review.googlesource.com/127135
Reviewed-by: Rob Pike <r@golang.org>
The existing implementation panics on malformed input of an empty
string. strconv.Unquote validates the length of the inputs, but calling
UnquoteChar directly with an empty string leads to a panic, so add a
check for length. Also, add a test to go/constant to ensure that
MakeFromLiteral does not panic on malformed input such as
"const x = ''".
Change-Id: I4217e38db48a09a21ec414bbfb3087709da62904
Reviewed-on: https://go-review.googlesource.com/116215
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Each URL was manually verified to ensure it did not serve up incorrect
content.
Change-Id: I4dc846227af95a73ee9a3074d0c379ff0fa955df
Reviewed-on: https://go-review.googlesource.com/115798
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Changed the example to convey the intent of the Unquote function
in a more succint way.
Fixes#23693
Change-Id: I49465641d730e70b5af0d47057335af39882bcec
Reviewed-on: https://go-review.googlesource.com/92015
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
The strconv shifts table is 320 bytes (amd64) and is present in
many binaries since integer formatting is very common.
Instead of using a precalculated table with shift amounts
use a bounded bits.TrailingZeros to determine the shift amount
to format numbers in a base that is a power of 2.
amd64:
name old time/op new time/op delta
AppendUint 379ns ± 1% 286ns ± 2% -24.62% (p=0.000 n=20+19)
Change-Id: Ib94d9b033321b41e975868943c7fcd9428c5111e
Reviewed-on: https://go-review.googlesource.com/110478
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Replaces " \t" code indentation with "\t".
Issues like this are easy to spot with editor that prints
whitespace charecters.
Change-Id: Ia82877e7c99121bf369fa76e46ba52dff84f36bf
Reviewed-on: https://go-review.googlesource.com/101355
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
I found files to change with this command:
git grep 'DO NOT EDIT' | grep -v 'Code generated .* DO NOT'
There are more files that match that grep, but I do not intend on fixing
them.
Change-Id: I4b474f1c29ca3135560d414785b0dbe0d1a4e52c
GitHub-Last-Rev: 65804b0263
GitHub-Pull-Request: golang/go#24334
Reviewed-on: https://go-review.googlesource.com/99955
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Also includes all derived values as well as
vendored packages.
Generated by running
UNICODE_VERSION=10.0.0 go generate
in golang.org/x/text
and modified by hand to add the tests and
entries in next.txt for new script and properties.
Closes Issue #21471
Change-Id: I1d10ee3887bd1fd3d5a756ee0d04bd6ec2814ba1
Reviewed-on: https://go-review.googlesource.com/63953
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Bonventre <andybons@golang.org>
Went mainly for the ones that make no sense, such as the ones
mid-sentence or after commas.
Change-Id: Ie245d2c19cc7428a06295635cf6a9482ade25ff0
Reviewed-on: https://go-review.googlesource.com/57293
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Move variable declarations closer to their first uses.
Use an additional string variable s0 for error reporting that references
the original input string. This allows the variable s to be modified.
Change-Id: I4725152490ca1dc10c1161ad8ad2f4ae8933493f
Reviewed-on: https://go-review.googlesource.com/55138
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Remove goto and use helper functions in ParseUint to create errors.
Change-Id: I1c4677ae1b9980db79065a9f8ca1f2c470249505
Reviewed-on: https://go-review.googlesource.com/55135
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Instead of printing Atoi as function name for test failures
print the actual function name and arguments tested.
Add a base field to the parseUint64BaseTests for consistency with
the parseInt64BaseTests tests.
Change-Id: Ib9891bdb87b62672b4216625212acfe6474c70fc
Reviewed-on: https://go-review.googlesource.com/55136
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
If needed cast the test table values to a higher bit size
integer type instead of casting the result values of the
tested function to a lower bit size integer type.
Change-Id: Iaa79742b2b1d90c7c7eac324f54032ebea0b1b41
Reviewed-on: https://go-review.googlesource.com/55137
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
If the value corresponding to the input string cannot be
represented by an unsigned integer of the given size,
err.Err = ErrRange and the returned value is the maximum
magnitude unsigned integer of the appropriate bitSize.
This is consistent with ParseInt's behavior and the documentation.
Expand tests to test 32 bit test value tables with bitsize 32 set.
These tests fail without the fix in this CL.
Fixes#21278
Change-Id: I8aab39279ec3e31905fcbf582a916cbf6d9b95da
Reviewed-on: https://go-review.googlesource.com/55134
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Missed in CL 49253 because I submitted from the Gerrit UI and
had not mailed the latest copy. Sigh.
Change-Id: I540f960278df43e2eaf1aac188eb124a1ff240dd
Reviewed-on: https://go-review.googlesource.com/49256
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
The init func was using testing.Short, but that's not available
until after flag parsing. Found by CL 49251.
Change-Id: Ia7b871043375260873fa2c7e81e1d43c1c83d33f
Reviewed-on: https://go-review.googlesource.com/49253
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This reduces memory use yet still provides the significant
performance gain seen when using a fast path for small integers.
Improvement of this CL comparing to code without fast path:
name old time/op new time/op delta
FormatIntSmall-8 35.6ns ± 1% 4.5ns ± 1% -87.30% (p=0.008 n=5+5)
AppendIntSmall-8 17.4ns ± 1% 9.4ns ± 3% -45.70% (p=0.008 n=5+5)
For comparison, here's the improvement before this CL to code without
fast path (1% better for FormatIntSmall):
name old time/op new time/op delta
FormatIntSmall-8 35.6ns ± 1% 4.0ns ± 3% -88.64% (p=0.008 n=5+5)
AppendIntSmall-8 17.4ns ± 1% 8.2ns ± 1% -52.80% (p=0.008 n=5+5)
Thus, the code in this CL performs slower for small integers using fast
path then the prior version, but this is relative to an already very fast
version:
name old time/op new time/op delta
FormatIntSmall-8 4.05ns ± 3% 4.52ns ± 1% +11.81% (p=0.008 n=5+5)
AppendIntSmall-8 8.21ns ± 1% 9.45ns ± 3% +15.05% (p=0.008 n=5+5)
Measured on 2.3 GHz Intel Core i7 running macOS Sierra 10.12.3.
Overall, it's still ~88% faster than without fast path for small integers,
so probably worth it as it removes 100 global string slices in favor of
a single string.
Credits: This is based on the original (but cleaned up) version of the
code by Aliaksandr Valialkin (https://go-review.googlesource.com/c/37963/).
Change-Id: Icda78679c8c14666d46257894e9fa3d7f35e58b8
Reviewed-on: https://go-review.googlesource.com/38319
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Some of the changes in CL golang.org/cl/38071/ assumed that / and %
could always be combined to use only one DIV instruction. However,
this is not the case for 64bit operands on a 32bit platform which use
seperate runtime functions to calculate division and modulo.
This CL restores the original optimizations that help on 32bit platforms
with negligible impact on 64bit platforms.
386:
name old time/op new time/op delta
FormatInt-2 6.06µs ± 0% 6.02µs ± 0% -0.70% (p=0.000 n=20+20)
AppendInt-2 4.98µs ± 0% 4.98µs ± 0% ~ (p=0.747 n=18+18)
FormatUint-2 1.93µs ± 0% 1.85µs ± 0% -4.19% (p=0.000 n=20+20)
AppendUint-2 1.71µs ± 0% 1.64µs ± 0% -3.68% (p=0.000 n=20+20)
amd64:
name old time/op new time/op delta
FormatInt-2 2.41µs ± 0% 2.41µs ± 0% -0.09% (p=0.010 n=18+18)
AppendInt-2 1.77µs ± 0% 1.77µs ± 0% +0.08% (p=0.000 n=18+18)
FormatUint-2 653ns ± 1% 653ns ± 0% ~ (p=0.178 n=20+20)
AppendUint-2 514ns ± 0% 513ns ± 0% -0.13% (p=0.000 n=20+17)
Change-Id: I574a18e54fb41b25fbe51ce696e7a8765abc79a6
Reviewed-on: https://go-review.googlesource.com/38051
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
The compiler recognizes that in a sequence q = x/y; r = x%y only
one division is required. Remove prior work-arounds and write
more readable straight-line code (this also results in fewer
instructions, though it doesn't appear to affect the benchmarks
significantly).
name old time/op new time/op delta
FormatInt-8 2.95µs ± 1% 2.92µs ± 5% ~ (p=0.952 n=5+5)
AppendInt-8 1.91µs ± 1% 1.89µs ± 2% ~ (p=0.421 n=5+5)
FormatUint-8 795ns ± 2% 782ns ± 4% ~ (p=0.444 n=5+5)
AppendUint-8 557ns ± 1% 557ns ± 2% ~ (p=0.548 n=5+5)
https://perf.golang.org/search?q=upload:20170310.1
Also:
- use uint instead of uintptr where we want to guarantee single-
register operations
- remove some unnecessary conversions (before indexing)
- add more comments and fix some comments
Change-Id: I04858dc2d798a6495879d9c7cfec2fdc2957b704
Reviewed-on: https://go-review.googlesource.com/38071
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
