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proposal: permit blank (_) separator in integer number literals #28493

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griesemer opened this issue Oct 30, 2018 · 82 comments
Closed

proposal: permit blank (_) separator in integer number literals #28493

griesemer opened this issue Oct 30, 2018 · 82 comments

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@griesemer
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@griesemer griesemer commented Oct 30, 2018

This has come up before, specifically during discussions of #19308 and #28256. I am writing this down so we have a place for discussing this independently. I have no strong feelings about this proposal either way.

Proposal

This is a fully backward-compatible proposal for permitting the use of a blank (_) as a separator in number literals. Specifically, we change the integer literal syntax such that we also allow a "_" after the first digit (the change is the extra "_"):

int_lit = decimal_lit | octal_lit | hex_lit .
decimal_lit = ( "1" … "9" ) { decimal_digit | "_" } .
octal_lit = "0" { octal_digit | "_" } .
hex_lit = "0" ( "x" | "X" ) hex_digit { hex_digit | "_" } .

And we change the floating-point number literal syntax correspondingly (the change is the extra "_"):

float_lit = decimals "." [ decimals ] [ exponent ] | decimals exponent | "." decimals [ exponent ] .
decimals = decimal_digit { decimal_digit | "_" } .
exponent = ( "e" | "E" ) [ "+" | "-" ] decimals .

For complex number literals the change is implied by the change to floating-point literals.

Examples:

123_456_789
1_000_000_000
0b0110_1101_1101_0010  // if we had binary integer literals
0xdead_beef
3.1415_9265

but also:

0___         // 0
0_77         // 77 decimal, or perhaps not permitted (TBD)
01_10        // 0110 (octal)
1_2__3___    // 123
0x1_23_0     // 0x1230
0__.0__e-0__ // 0.0e-0

Discussion

The notation follows more or less the syntax used in other languages (e.g., Swift).
The implementation is straight-forward (a minor change to the number scanner). As the examples show, the separator, if judiciously used, may improve readability; or it may degrade it significantly.
A tool (go vet) might impose restrictions on how the separator is used for readability.

@ericlagergren
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@ericlagergren ericlagergren commented Oct 30, 2018

What would be the reason for allowing the underscore to appear anywhere instead of limiting it to (multiples of) commonly used places? E.g.,

1_000_000_000
0xDEAD_BEEF
0b0101_1111_0001

ISTM being too permissive only degrades readability.

@dgryski
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@dgryski dgryski commented Oct 30, 2018

@ericlagergren It seems more Go-like to leave the grammar more free-form with regards to placement of _, but leave the enforcement of style (how many digits in each group) to tooling and code review.

@ericlagergren
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@ericlagergren ericlagergren commented Oct 30, 2018

@griesemer
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@griesemer griesemer commented Oct 30, 2018

@ericlagergren What's a commonly used placement of _? That's really difficult to impossible to answer and shouldn't be decided by the language. Also, note that other languages also don't try to pin that down.

@ericlagergren
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@ericlagergren ericlagergren commented Oct 30, 2018

@alanfo
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@alanfo alanfo commented Oct 31, 2018

I think this is an excellent idea if we are to have binary literals (which otherwise become unreadable after one or two bytes) and also helps with the readability of other long numbers.

Several other languages have a similar feature.

As far as placement is concerned, we'll just have to leave that to the good taste of gophers :)

@davecheney
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@davecheney davecheney commented Oct 31, 2018

I don’t think this improves readability. For example, which is more readable?

x := 100000000
y := 100_000_000
const million = 1000000
z := 100 * million

The latter is, IMO, the more descriptive, leverages the qualities of untyped constants, the lineage of the time package, and exists today without new syntax.

@alanfo
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@alanfo alanfo commented Oct 31, 2018

Well, exact powers of 10 can always be dealt with in some other manner. One could also do this:

z2 := int(1e8)

But what about these:

// binary literals
a := 0b0101110110011011
b := 0b01011101_10011011 // bytes
c := 0b0101_1101_1001_1011 // nybbles

// decimal literals
d := 2861945612983
e := 2_861_945_612_983 // thousand separators

To my eyes, the underscored literals are much easier to read.

@mundaym
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@mundaym mundaym commented Oct 31, 2018

Are there any concrete examples of existing code where this would help readability significantly? Adding a separator does make sense for big numbers but are they common enough to warrant changing the language for?

I've spent a bit of time working with Swift code and in my limited experience I've seen that underscores tend to get used inconsistently. I think they end up making it harder (for me anyway) to parse the code.

Go already has quite a few ways to write constants, I'm not sure we need more.

@alanfo
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@alanfo alanfo commented Oct 31, 2018

When programming in other languages which have digit separators (C#, Java, Kotlin), I generally split binary literals into nybbles and add thousand separators for decimal literals >= 1,000. That more or less mimics how I'd write them down on paper (with space and comma as respective separators).

Of course, that doesn't mean I find longer numbers without separators unreadable - I'm OK up to about twice those lengths - but, when you have something, you tend to use it.

Very long decimal literals don't crop up very often (except perhaps powers of 10) but when they do it really is good to have the digit separator in the toolbox :)

If this proposal is accepted, then no doubt there will be people who abuse it or use it inconsistently but I don't really think it is practical to limit placement in some way. Other languages don't seem to bother either.

@deanveloper
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@deanveloper deanveloper commented Oct 31, 2018

@RalphCorderoy
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@RalphCorderoy RalphCorderoy commented Oct 31, 2018

I think it would be better to rule out adjacent or trailing underscores, and to always want at least one digit between the base indicator and the first underscore, e.g. 0_7 is invalid, effectively ruling out a leading underscore on the value's digits.

int_lit = decimal_lit | octal_lit | hex_lit .
decimal_lit = ( "1" … "9" ) { decimal_digit | "_" decimal_digit } .
octal_lit = "0" [ octal_digit { octal_digit | "_" octal_digit } ] .
hex_lit = "0" ( "x" | "X" ) hex_digit { hex_digit | "_" hex_digit } .
@griesemer
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@griesemer griesemer commented Oct 31, 2018

@RalphCorderoy Note that the proposed syntax already requires at least one digit after the base indicator before the first blank (_). Based on that rule, 0_7 would be decimal 7; but for this specific case of octals, I agree it should be invalid.

I'm not convinced about ruling out adjacent separators. For one, other languages permit it, and not permitting it would truly make the literal syntax quite a bit more complex. As is, it simply follows the same pattern we already have for identifiers.

Also, consider as a counter-example: 0b0110_0111_1010_1100__0011_0100_0101_1100 .

@RalphCorderoy
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@RalphCorderoy RalphCorderoy commented Oct 31, 2018

Hi @griesemer, the double underscore for a 16-bit boundary is a good example of why it should be permitted.

With leading underscores, including octal, ruled out, is there a reason to permit trailing ones? It's allowed in identifiers, but this change is about separating digits for readability. The lexing of 42_____x can complain about the trailing _ on peeking the x because lexing as 42 and _____x instead, after much backtracking, wouldn't be valid for later parsing anyway AFAIK.

@deanveloper
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@deanveloper deanveloper commented Oct 31, 2018

0_77 // 77 decimal, or perhaps not permitted (TBD)

Definitely should not be permitted. It looks like the proposed syntax prevents this though.

[...] is there a reason to permit trailing ones? It's allowed in identifiers [...]

I can't think of any reasons. Also, identifiers allow leading underscores as well, and we've ruled those out so I'm not sure if that logic applies

@cznic
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@cznic cznic commented Oct 31, 2018

This is a fully backward-compatible proposal for permitting the use of a blank (_) as a separator in number literals.

I don't think this is the case. Currently 123_456 forms three valid tokens while under the proposal it would become just one.

I'm aware the compatibility guarantee is narrowed to "continues to compile", but that's not the same as "fully backwards compatible", as that should IMHO include not breaking also any of the existing tools.

@magical
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@magical magical commented Oct 31, 2018

@cznic As you say, the compatibility guarantee only says that valid code will continue to work; it makes no particular guarantees about invalid code.

The cost of updating tools to support new language features is something that has to be considered with any language change, but that is a separate issue from backward compatibility.

@rasky
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@rasky rasky commented Nov 1, 2018

While doing embedded programming, I often use hexadecimal constants and I feel that 0x0f00_0000 is a big readability improvement over 0x0f000000, as it's too easy to miss a digit.

@seaskyways
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@seaskyways seaskyways commented Nov 1, 2018

1+
This feature has been implemented lately in Kotlin and has been of great help. Would love to see it in Golang!

@deanveloper
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@deanveloper deanveloper commented Nov 1, 2018

I don’t think this improves readability. For example, which is more readable?

x := 100000000
y := 100_000_000
const million = 1000000
z := 100 * million

The latter is, IMO, the more descriptive, leverages the qualities of untyped constants, the lineage of the time package, and exists today without new syntax.
@davecheney

For simple, small(er) numbers, this argument holds. But it starts breaking down once we start talking about numbers that are larger than a billion. I'd rather not have to look back and count 9 zeroes just to verify that 100000000 is actually a billion so that I can do 5 * billion.

The argument also starts to break down when we start to talk about numbers which aren't as simple as 100 million, for instance, a large prime number 10107476689

x := 10_107_476_689

// alternatively
const thousand = 1000
const million = thousand * 1000;
const billion = million * 1000;
y := 10 * billion + 107 * million + 476 * thousand + 689

The argument also breaks down when you're not talking about decimal notation, which has already been brought up so I won't go into depth, but it's very useful to be able to break up binary/hex into nybbles/bytes.

PS - the 100000000 in the first paragraph only contains 8 zeroes, which was done to illustrate that your solution starts to break down a bit once you have larger numbers

@tomvanwoow
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@tomvanwoow tomvanwoow commented Nov 1, 2018

I don't believe it is a good idea to enforce restrictions on where the underscores must go, as I can imagine some people preferring 1234_567_890 to 1_234_567_890. It should be down the coder to write nice looking code.

@theodesp
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@theodesp theodesp commented Nov 5, 2018

It looks like this proposal is very similar to Python's PEP-515

Ideally, we would also like to have rules for fmt also. For example:

a := 10107476689
fmt.Printf("%#_d", a) // 10_107_476_689
fmt.Printf("%#_x", a) // '2_5a73_dad1'
@deanveloper
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@deanveloper deanveloper commented Nov 5, 2018

@theodesp again I bring up international number formatting

Is there any reason to put it in fmt? We do not have comma separators in fmt today, and I think for good reason. Number formats are localized, so I'm not sure if it's a good idea for fmt. Maybe it'd be good for the text package, but we already have comma separation there, so I don't see much use

Also, the # parameter is already taken by "alternate form". For instance, it adds a leading "0x" for "%x". Not sure if you knew this or not. If you did, you forgot to put it in your outputs, and there is no "%#d". If you didn't, well I hope you learned something new 😃

@theodesp
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@theodesp theodesp commented Nov 5, 2018

I knew it, this was just an example extension to the existing flags. I use fmt because its the most obvious choice and I don't think the underscores are part of any sort of internationalization as the scope of this proposal is totally different.

@deanveloper
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@deanveloper deanveloper commented Nov 5, 2018

The main point that I was making was that separating by 3s is localized - the Indian number format does not do this. Go forces the "." separator in fmt because it's part of the language, but separating numbers by 3s is not part of the language, so I'm not sure if that's in the scope of fmt

nebulabox added a commit to nebulabox/go that referenced this issue Feb 20, 2019
R=Go1.13

Updates golang#12711.
Updates golang#19308.
Updates golang#28493.
Updates golang#29008.

Change-Id: Icd25aa7f6e18ed671ea6cf2b1b292899daf4b1a5
Reviewed-on: https://go-review.googlesource.com/c/160018
Reviewed-by: Russ Cox <rsc@golang.org>
nebulabox added a commit to nebulabox/go that referenced this issue Feb 20, 2019
This CL introduces go/constant support for the new binary and octal integer
literals, hexadecimal floats, and digit separators for all number literals.

R=Go1.13

Updates golang#12711.
Updates golang#19308.
Updates golang#28493.
Updates golang#29008.

Change-Id: I7a55f91b8b6373ae6d98ba923b626d33c5552946
Reviewed-on: https://go-review.googlesource.com/c/160239
Reviewed-by: Russ Cox <rsc@golang.org>
nebulabox added a commit to nebulabox/go that referenced this issue Feb 20, 2019
This CL ensures that go/types can now handle the new
Go 2 number literals. The relevant changes enabling
them in go/types were made in go/constant in the CL
https://golang.org/cl/160239.

R=Go1.13

Updates golang#12711.
Updates golang#19308.
Updates golang#28493.
Updates golang#29008.

Change-Id: I45c1387198fac94769ac59c5301d86b4e1a1ff98
Reviewed-on: https://go-review.googlesource.com/c/160240
Reviewed-by: Russ Cox <rsc@golang.org>
nebulabox added a commit to nebulabox/go that referenced this issue Feb 20, 2019
This CL introduces text/scanner support for the new binary and octal integer
literals, hexadecimal floats, and digit separators for all number literals.
The new code is closely mirroring the respective code for number literals in
cmd/compile/internal/syntax/scanner.go.

Uniformly use the term "invalid" rather than "illegal" in error messages
to match the respective error messages in the other scanners directly.

R=Go1.13

Updates golang#12711.
Updates golang#19308.
Updates golang#28493.
Updates golang#29008.

Change-Id: I2f291de13ba5afc0e530cd8326e6bf4c3858ebac
Reviewed-on: https://go-review.googlesource.com/c/161199
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
nebulabox added a commit to nebulabox/go that referenced this issue Feb 20, 2019
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 golang#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>
@gopherbot
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@gopherbot gopherbot commented Feb 20, 2019

Change https://golang.org/cl/163079 mentions this issue: text/scanner: don't liberally consume (invalid) floats or underbars

gopherbot pushed a commit that referenced this issue Feb 20, 2019
This is a follow-up on https://golang.org/cl/161199 which introduced
the new Go 2 number literals to text/scanner.

That change introduced a bug by allowing decimal and hexadecimal floats
to be consumed even if the scanner was not configured to accept floats.

This CL changes the code to not consume a radix dot '.' or exponent
unless the scanner is configured to accept floats.

This CL also introduces a new mode "AllowNumberbars" which controls
whether underbars '_' are permitted as digit separators in numbers
or not.

There is a possibility that we may need to refine text/scanner
further (e.g., the Float mode now includes hexadecimal floats
which it didn't recognize before). We're very early in the cycle,
so let's see how it goes.

RELNOTE=yes

Updates #12711.
Updates #19308.
Updates #28493.
Updates #29008.

Fixes #30320.

Change-Id: I6481d314f0384e09ef6803ffad38dc529b1e89a3
Reviewed-on: https://go-review.googlesource.com/c/163079
Reviewed-by: Ian Lance Taylor <iant@golang.org>
nebulabox added a commit to nebulabox/go that referenced this issue Feb 21, 2019
This is a follow-up on https://golang.org/cl/161199 which introduced
the new Go 2 number literals to text/scanner.

That change introduced a bug by allowing decimal and hexadecimal floats
to be consumed even if the scanner was not configured to accept floats.

This CL changes the code to not consume a radix dot '.' or exponent
unless the scanner is configured to accept floats.

This CL also introduces a new mode "AllowNumberbars" which controls
whether underbars '_' are permitted as digit separators in numbers
or not.

There is a possibility that we may need to refine text/scanner
further (e.g., the Float mode now includes hexadecimal floats
which it didn't recognize before). We're very early in the cycle,
so let's see how it goes.

RELNOTE=yes

Updates golang#12711.
Updates golang#19308.
Updates golang#28493.
Updates golang#29008.

Fixes golang#30320.

Change-Id: I6481d314f0384e09ef6803ffad38dc529b1e89a3
Reviewed-on: https://go-review.googlesource.com/c/163079
Reviewed-by: Ian Lance Taylor <iant@golang.org>
gopherbot pushed a commit that referenced this issue Feb 26, 2019
This CL updates fmt's scanner to accept the new number syntaxes:

 - Hexadecimal floating-point values.
 - Digit-separating underscores.
 - Leading 0b and 0o prefixes.

See golang.org/design/19308-number-literals for background.

For #12711.
For #19308.
For #28493.
For #29008.

Change-Id: I5582af5c94059c781e6cf4e862441d3df3006adf
Reviewed-on: https://go-review.googlesource.com/c/160247
Reviewed-by: Robert Griesemer <gri@golang.org>
gopherbot pushed a commit that referenced this issue Feb 26, 2019
This CL updates text/template's scanner to accept the
new number syntaxes:

 - Hexadecimal floating-point values.
 - Digit-separating underscores.
 - Leading 0b and 0o prefixes.

See golang.org/design/19308-number-literals for background.

For #12711.
For #19308.
For #28493.
For #29008.

Change-Id: I68c16ea35c3f506701063781388de72bafee6b8d
Reviewed-on: https://go-review.googlesource.com/c/160248
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
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@gopherbot gopherbot commented Mar 9, 2019

Change https://golang.org/cl/166157 mentions this issue: math/big: add support for underscores '_' in numbers

@gopherbot
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@gopherbot gopherbot commented Mar 9, 2019

Change https://golang.org/cl/166417 mentions this issue: cmd/compile: remove work-arounds for handling underscores in numbers

gopherbot pushed a commit that referenced this issue Mar 12, 2019
This CL documents the new binary and octal integer literals,
hexadecimal floats, generalized imaginary literals and digit
separators for all number literals in the spec.

Added empty lines between abutting paragraphs in some places
(a more thorough cleanup can be done in a separate CL).

A minor detail: A single 0 was considered an octal zero per the
syntax (decimal integer literals always started with a non-zero
digit). The new octal literal syntax allows 0o and 0O prefixes
and when keeping the respective octal_lit syntax symmetric with
all the others (binary_lit, hex_lit), a single 0 is not automatically
part of it anymore. Rather than complicating the new octal_lit syntax
to include 0 as before, it is simpler (and more natural) to accept
a single 0 as part of a decimal_lit. This is purely a notational
change.

R=Go1.13

Updates #12711.
Updates #19308.
Updates #28493.
Updates #29008.

Change-Id: Ib9fdc6e781f6031cceeed37aaed9d05c7141adec
Reviewed-on: https://go-review.googlesource.com/c/go/+/161098
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
gopherbot pushed a commit that referenced this issue Mar 12, 2019
The primary change is in nat.scan which now accepts underscores for base 0.
While at it, streamlined error handling in that function as well.
Also, improved the corresponding test significantly by checking the
expected result values also in case of scan errors.

The second major change is in scanExponent which now accepts underscores when
the new sepOk argument is set. While at it, essentially rewrote that
function to match error and underscore handling of nat.scan more closely.
Added a new test for scanExponent which until now was only tested
indirectly.

Finally, updated the documentation for several functions and added many
new test cases to clients of nat.scan.

A major portion of this CL is due to much better test coverage.

Updates #28493.

Change-Id: I7f17b361b633fbe6c798619d891bd5e0a045b5c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/166157
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
gopherbot pushed a commit that referenced this issue Mar 12, 2019
With math/big supporting underscores directly, there is no need to
manually remove them before calling the math/big conversion routines.

Updates #28493.

Change-Id: I6f865c8f87c3469ffd6c33f960ed540135055226
Reviewed-on: https://go-review.googlesource.com/c/go/+/166417
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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@gopherbot gopherbot commented May 2, 2019

Change https://golang.org/cl/174897 mentions this issue: cmd/compile: disable Go1.13 language features for -lang=go1.12 and below

gopherbot pushed a commit that referenced this issue May 2, 2019
Fixes   #31747.
Updates #19308.
Updates #12711.
Updates #29008.
Updates #28493.
Updates #19113.

Change-Id: I76d2fdbc7698cc4e0f31b7ae24cbb4d28afbb6a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/174897
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
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@rsc rsc commented May 7, 2019

As a reminder, we introduced a new process for these Go 2-related language changes in our blog post blog.golang.org/go2-here-we-come. The Go 1.13 development cycle is now over and it’s time for the final decision.

The feedback on the Go 2 number literal changes has been strongly positive, with very few negative voices. These changes modernize and harmonize Go’s number literal syntax without adding significant complexity to the language: There is now a uniform prefix notation for the three common non-decimal number bases, which matches the notation used in other modern programming languages. The introduction of hexadecimal floating-point literals addresses a pain point for people concerning themselves with numeric code. The suffix “i” may now be used with any (non-imaginary) number literal to create an imaginary constant in a uniform way. And finally, underscores may be used to split longer literals into groups of digits for improved readability.

Proposal accepted for Go 1.13. Closing because the changes have landed.

- rsc for proposal review

@rsc rsc closed this May 7, 2019
Kiku-Reise added a commit to Kiku-Reise/go that referenced this issue May 16, 2019
fix (#1)
* cmd/compile: add unsigned divisibility rules

"Division by invariant integers using multiplication" paper
by Granlund and Montgomery contains a method for directly computing
divisibility (x%c == 0 for c constant) by means of the modular inverse.
The method is further elaborated in "Hacker's Delight" by Warren Section 10-17

This general rule can compute divisibilty by one multiplication and a compare
for odd divisors and an additional rotate for even divisors.

To apply the divisibility rule, we must take into account
the rules to rewrite x%c = x-((x/c)*c) and (x/c) for c constant on the first
optimization pass "opt".  This complicates the matching as we want to match
only in the cases where the result of (x/c) is not also available.
So, we must match on the expanded form of (x/c) in the expression x == c*(x/c)
in the "late opt" pass after common subexpresion elimination.

Note, that if there is an intermediate opt pass introduced in the future we
could simplify these rules by delaying the magic division rewrite to "late opt"
and matching directly on (x/c) in the intermediate opt pass.

Additional rules to lower the generic RotateLeft* ops were also applied.

On amd64, the divisibility check is 25-50% faster.

name                     old time/op  new time/op  delta
DivconstI64-4            2.08ns ± 0%  2.08ns ± 1%     ~     (p=0.881 n=5+5)
DivisibleconstI64-4      2.67ns ± 0%  2.67ns ± 1%     ~     (p=1.000 n=5+5)
DivisibleWDivconstI64-4  2.67ns ± 0%  2.67ns ± 0%     ~     (p=0.683 n=5+5)
DivconstU64-4            2.08ns ± 1%  2.08ns ± 1%     ~     (p=1.000 n=5+5)
DivisibleconstU64-4      2.77ns ± 1%  1.55ns ± 2%  -43.90%  (p=0.008 n=5+5)
DivisibleWDivconstU64-4  2.99ns ± 1%  2.99ns ± 1%     ~     (p=1.000 n=5+5)
DivconstI32-4            1.53ns ± 2%  1.53ns ± 0%     ~     (p=1.000 n=5+5)
DivisibleconstI32-4      2.23ns ± 0%  2.25ns ± 3%     ~     (p=0.167 n=5+5)
DivisibleWDivconstI32-4  2.27ns ± 1%  2.27ns ± 1%     ~     (p=0.429 n=5+5)
DivconstU32-4            1.78ns ± 0%  1.78ns ± 1%     ~     (p=1.000 n=4+5)
DivisibleconstU32-4      2.52ns ± 2%  1.26ns ± 0%  -49.96%  (p=0.000 n=5+4)
DivisibleWDivconstU32-4  2.63ns ± 0%  2.85ns ±10%   +8.29%  (p=0.016 n=4+5)
DivconstI16-4            1.54ns ± 0%  1.54ns ± 0%     ~     (p=0.333 n=4+5)
DivisibleconstI16-4      2.10ns ± 0%  2.10ns ± 1%     ~     (p=0.571 n=4+5)
DivisibleWDivconstI16-4  2.22ns ± 0%  2.23ns ± 1%     ~     (p=0.556 n=4+5)
DivconstU16-4            1.09ns ± 0%  1.01ns ± 1%   -7.74%  (p=0.000 n=4+5)
DivisibleconstU16-4      1.83ns ± 0%  1.26ns ± 0%  -31.52%  (p=0.008 n=5+5)
DivisibleWDivconstU16-4  1.88ns ± 0%  1.89ns ± 1%     ~     (p=0.365 n=5+5)
DivconstI8-4             1.54ns ± 1%  1.54ns ± 1%     ~     (p=1.000 n=5+5)
DivisibleconstI8-4       2.10ns ± 0%  2.11ns ± 0%     ~     (p=0.238 n=5+4)
DivisibleWDivconstI8-4   2.22ns ± 0%  2.23ns ± 2%     ~     (p=0.762 n=5+5)
DivconstU8-4             0.92ns ± 1%  0.94ns ± 1%   +2.65%  (p=0.008 n=5+5)
DivisibleconstU8-4       1.66ns ± 0%  1.26ns ± 1%  -24.28%  (p=0.008 n=5+5)
DivisibleWDivconstU8-4   1.79ns ± 0%  1.80ns ± 1%     ~     (p=0.079 n=4+5)

A follow-up change will address the signed division case.

Updates #30282

Change-Id: I7e995f167179aa5c76bb10fbcbeb49c520943403
Reviewed-on: https://go-review.googlesource.com/c/go/+/168037
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

* cmd/link/internal/ld: consolidate macho platform setup

Determine the macho platform once and use that the two places that
need it. This makes it easier to add a third platform check for a
follow-up change.

Updates #31447

Change-Id: I522a5fface647ab8e608f816c5832d531534df7a
Reviewed-on: https://go-review.googlesource.com/c/go/+/174198
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

* cmd/link/internal/ld,syscall: drop $INODE64 suffixes on simulators

Some libc functions are suffixed with "$INODE64" on macOS.
Unfortunately, the iOS simulator doesn't have the suffixes, so we can't
use GOARCH to distinguish the two platform.

Add linker support for adding the suffix, using the macho platform
to determine whether it is needed.

While here, add the correct suffix for fdopendir on 386. It's
"$INODE64$UNIX2003", believe it or not. Without the suffix,

GOARCH=386 go test -short syscall

crashes on my Mojave machine.

Fixes #31447

Change-Id: I9bd3de40ece7df62f744bc24cd00909e56b00b78
Reviewed-on: https://go-review.googlesource.com/c/go/+/174199
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

* cmd/link/internal/ld,syscall: replace getfsstat64 with getfsstat

getfsstat64 is deprecated but not yet caught by the App Store checks.
Use the supported getfsstat$INODE64 form instead to ensure forward
compatibility.

Change-Id: I0d97e8a8b254debb3de1cfcb3778dbed3702c249
Reviewed-on: https://go-review.googlesource.com/c/go/+/174200
Run-TryBot: Elias Naur <mail@eliasnaur.com>
Reviewed-by: Keith Randall <khr@golang.org>

* cmd/go/internal/renameio: use ERROR_ACCESS_DENIED to check for errors

CL 172418 added code to check for "Access is denied" error.
But "Access is denied" error will be spelled differently on
non-English version of Windows.

Check if error is ERROR_ACCESS_DENIED instead.

Updates #31247

Change-Id: I7b1633013d563f7c06c1f12a9be75122106834f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/174123
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>

* syscall: allow setting security attributes on processes

This allows creating processes that can only be debugged/accessed by
certain tokens, according to a particular security descriptor. We
already had everything ready for this but just neglected to pass through
the value from the user-accessible SysProcAttr.

Change-Id: I4a3fcc9f5078aa0058b26c103355c984093ae03f
Reviewed-on: https://go-review.googlesource.com/c/go/+/174197
Run-TryBot: Jason Donenfeld <Jason@zx2c4.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

* runtime: remove spurious register loads for openbsd/amd64 kqueue

The kqueue system call takes no arguments, hence there should be no need
to zero the registers used for the first syscall arguments.

Change-Id: Ia79b2d4f4d568bb6795cb885e1464cf1fc2bf7c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/174128
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>

* cmd/compile: intrinsify math/bits.Add64 for ppc64x

This change creates an intrinsic for Add64 for ppc64x and adds a
testcase for it.

name               old time/op  new time/op  delta
Add64-160          1.90ns ±40%  2.29ns ± 0%     ~     (p=0.119 n=5+5)
Add64multiple-160  6.69ns ± 2%  2.45ns ± 4%  -63.47%  (p=0.016 n=4+5)

Change-Id: I9abe6fb023fdf62eea3c9b46a1820f60bb0a7f97
Reviewed-on: https://go-review.googlesource.com/c/go/+/173758
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Run-TryBot: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>

* runtime: whitelist debugCall32..debugCall65536 in debugCallCheck

Whitelists functions debugCall32 through debugCall65536 in
runtime.debugCallCheck so that any instruction inside those functions
is considered a safe point.
This is useful for implementing nested function calls.

For example when evaluating:

	f(g(x))

The debugger should:

1. initiate the call to 'f' until the entry point of 'f',
2. complete the call to 'g(x)'
3. copy the return value of 'g(x)' in the arguments of 'f'
4. complete the call to 'f'

Similarly for:

	f().amethod()

The debugger should initiate the call to '.amethod()', then initiate
and complete the call to f(), copy the return value to the arguments
of '.amethod()' and finish its call.
However in this example, unlike the other example, it may be
impossible to determine the entry point of '.amethod()' until after
'f()' is evaluated, which means that the call to 'f()' needs to be
initiated while stopped inside a debugCall... function.

Change-Id: I575c23542709cedb1a171d63576f7e11069c7674
Reviewed-on: https://go-review.googlesource.com/c/go/+/161137
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>

* strconv: Document ParseFloat's special cases

Updates #30990

Change-Id: I968fb13251ab3796328089046a3f0fc5c7eb9df9
Reviewed-on: https://go-review.googlesource.com/c/go/+/174204
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/go: implement Go checksum database support

This CL adds support for consulting the Go checksum database
when downloading a module that is not already listed in go.sum.
The overall system is described at golang.org/design/25530-sumdb,
and this CL implements the functionality described specifically in
golang.org/design/25530-sumdb#command-client.

Although the eventual plan is to set GOPROXY and GOSUMDB to
default to a Google-run proxy serving the public Go ecosystem,
this CL leaves them off by default.

Fixes #30601.

Change-Id: Ie46140f93c6cc2d85573fbce0878a258819ff44d
Reviewed-on: https://go-review.googlesource.com/c/go/+/173951
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* encoding/json: add a Fuzz function

Adds a sample Fuzz test function to package encoding/json following the
guidelines defined in #31309, based on
https://github.com/dvyukov/go-fuzz-corpus/blob/master/json/json.go

Fixes #31309
Updates #19109

Change-Id: I5fe04d9a5f41c0de339f8518dae30896ec14e356
Reviewed-on: https://go-review.googlesource.com/c/go/+/174058
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* all: remove a few unused parameters

I recently modified tabwriter to reduce the number of defers due to
flush calls. However, I forgot to notice that the new function
flushNoDefers can no longer return an error, due to the lack of the
defer.

In crypto/tls, hashForServerKeyExchange never returned a non-nil error,
so simplify the code.

Finally, in go/types and net we can find a few trivially unused
parameters, so remove them.

Change-Id: I54c8de83fbc944df432453b55c93008d7e810e61
Reviewed-on: https://go-review.googlesource.com/c/go/+/174131
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>

* net/http: remove "number:" from Response.Status string

The behavior of Value.String method on non-string JavaScript types has
changed after CL 169757.

Update the implementation of Transport.RoundTrip method to construct the
Response.Status string without relying on result.Get("status").String(),
since that now returns strings like "<number: 200>" instead of "200".

Fixes #31736

Change-Id: I27b3e6cc95aa65fd1918b1400e88478a154aad12
Reviewed-on: https://go-review.googlesource.com/c/go/+/174218
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>

* cmd/link/internal/s390x: fix s390x build

Fix breakage from CL 173437

Change-Id: If218ffaa1259fbdee641143ffbe4b38030c373b9
Reviewed-on: https://go-review.googlesource.com/c/go/+/174278
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

* net: correct docs of KeepAlive field in Dialer type

KeepAlive field used to report the wording "keep-alive period"
which may be misleading. This field does not represent the whole
TCP keepalive time, that is the inactivity period upon which one
endpoint starts probing the other end. But it acctually specifies
the keepalive interval, that is the time between two keepalive
probes.

Fixes #29089

Change-Id: If99b38ba108830d0e5fe527171a2f5c96a3bcde7
Reviewed-on: https://go-review.googlesource.com/c/go/+/155960
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* misc/wasm: fix command line arguments containing multi-byte characters

Command line arguments containing multi-byte characters were causing
go_js_wasm_exec to crash (RangeError: Source is too large), because
their byte length was not handled correctly. This change fixes the bug.

Fixes #31645.

Change-Id: I7860ebf5b12da37d9d0f43d4b6a22d326a90edaf
Reviewed-on: https://go-review.googlesource.com/c/go/+/173877
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* runtime: initialise cpu.HWCap on openbsd/arm64

OpenBSD does not provide auxv, however we still need to initialise cpu.HWCap.
For now initialise it to the bare minimum, until some form of CPU capability
detection is implemented or becomes available - see issue #31746.

Updates #31656

Change-Id: I68c3c069319fe60dc873f46def2a67c9f3d937d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/174129
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* runtime: support all as parameter in gdb goroutine commands.

For example, can use `goroutine all bt` to dump all goroutines'
information.

Change-Id: I51b547c2b837913e4bdabf0f45b28f09250a3e34
GitHub-Last-Rev: d04dcd4f581f97e35ee45969a864f1270d79e49b
GitHub-Pull-Request: golang/go#26283
Reviewed-on: https://go-review.googlesource.com/c/go/+/122589
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: David Chase <drchase@google.com>

* os/exec: always set SYSTEMROOT on Windows if not listed in Cmd.Env

Fixes #25210

Change-Id: If27b61776154dae9b9b67bf4e4f5faa785d98105
Reviewed-on: https://go-review.googlesource.com/c/go/+/174318
Reviewed-by: Ian Lance Taylor <iant@golang.org>

* runtime/cgo: ignore missing Info.plist files on iOS

When running Go programs on Corellium virtual iPhones, the Info.plist
files might not exist. Ignore the error.

Updates #31722

Change-Id: Id2e315c09346b69dda9e10cf29fb5dba6743aac4
Reviewed-on: https://go-review.googlesource.com/c/go/+/174202
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* syscall: don't return EINVAL on zero Chmod mode on Windows

Fixes #20858

Change-Id: I45c397795426aaa276b20f5cbeb80270c95b920c
Reviewed-on: https://go-review.googlesource.com/c/go/+/174320
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* testing: delay flag registration; move to an Init function

Any code that imports the testing package forces the testing flags to be
defined, even in non-test binaries. People work around this today by
defining a copy of the testing.TB interface just to avoid importing
testing.

Fix this by moving flag registration into a new function, testing.Init.
Delay calling Init until the testing binary begins to run, in
testing.MainStart.

Init is exported for cases where users need the testing flags to be
defined outside of a "go test" context. In particular, this may be
needed where testing.Benchmark is called outside of a test.

Fixes #21051

Change-Id: Ib7e02459e693c26ae1ba71bbae7d455a91118ee3
Reviewed-on: https://go-review.googlesource.com/c/go/+/173722
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* runtime: make mmap return 0 instead of -1 on aix/ppc64

Most of the platforms are returning 0 instead of -1 when mmap syscalls
is failing. This patch corrects it for AIX in order to fix
TestMmapErrorSign and to improve AIX compatibility.

Change-Id: I1dad88d0e69163ad55c504b2b4a997892fd876cd
Reviewed-on: https://go-review.googlesource.com/c/go/+/174297
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

* cmd/go: add XCOFF format handler for go version

Change-Id: Ib102ae95acfd89fc3c9942a4ec82c74362f62045
Reviewed-on: https://go-review.googlesource.com/c/go/+/174299
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

* runtime: account for callbacks in checkdead on Windows

When a callback runs on a different thread in Windows, as in the
runtime package test TestCallbackInAnotherThread, it will use the
extra M. That can cause the test in checkdead to fail incorrectly.
Check whether there actually is an extra M before expecting it.

I think this is a general problem unrelated to timers. I think the test
was passing previously because the timer goroutine was using an M.
But I haven't proved that. This change seems correct, and it avoids
the test failure when using the new timers on Windows.

Updates #27707

Change-Id: Ieb31c04ff0354d6fae7e173b59bcfadb8b0464cd
Reviewed-on: https://go-review.googlesource.com/c/go/+/174037
Reviewed-by: Keith Randall <khr@golang.org>

* cmd,runtime: enable cgo for openbsd/arm64

Updates #31656.

Change-Id: Ide6f829282fcdf20c67998b766a201a6a92c3035
Reviewed-on: https://go-review.googlesource.com/c/go/+/174132
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

* cmd/compile: evaluate map initializers incrementally

For the code:

m := map[int]int {
  a(): b(),
  c(): d(),
  e(): f(),
}

We used to do:

t1 := a()
t2 := b()
t3 := c()
t4 := d()
t5 := e()
t6 := f()
m := map[int]int{}
m[t1] = t2
m[t3] = t4
m[t5] = t6

After this CL we do:

m := map[int]int{}
t1 := a()
t2 := b()
m[t1] = t2
t3 := c()
t4 := d()
m[t3] = t4
t5 := e()
t6 := f()
m[t5] = t6

Ordering the initialization this way limits the lifetime of the
temporaries involved.  In particular, for large maps the number of
simultaneously live temporaries goes from ~2*len(m) to ~2. This change
makes the compiler (regalloc, mostly) a lot happier. The compiler runs
faster and uses a lot less memory.

For #26546, changes compile time of a big map from 8 sec to 0.5 sec.

Fixes #26552

Update #26546

Change-Id: Ib7d202dead3feaf493a464779fd9611c63fcc25f
Reviewed-on: https://go-review.googlesource.com/c/go/+/174417
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

* cmd/go: add test of $GONOPROXY, $GONOSUMDB behavior

Change-Id: I8a4917ce14ea22d5991226e485d43a9c9312950e
Reviewed-on: https://go-review.googlesource.com/c/go/+/174219
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

* encoding/json: fix Unmarshal hang on recursive pointers

indirect walks down v until it gets to a non-pointer. But it does not
handle the case when v is a pointer to itself, like in:

	var v interface{}
	v = &v
	Unmarshal(b, v)

So just stop immediately if we see v is a pointer to itself.

Fixes #31740

Change-Id: Ie396264119e24d70284cd9bf76dcb2050babb069
Reviewed-on: https://go-review.googlesource.com/c/go/+/174337
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* runtime: do not use heap arena hints on wasm

The address space of WebAssembly's linear memory is contiguous, so
requesting specific addresses is not supported. Do not use heap arena
hints so we do not have unused memory ranges.

This fixes go1 benchmarks on wasm which ran out of memory since
https://golang.org/cl/170950.

Change-Id: I70115b18dbe43abe16dd5f57996343d97bf94760
Reviewed-on: https://go-review.googlesource.com/c/go/+/174203
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

* cmd/internal/obj/wasm: cache SP in a local

We use Wasm global variables extensively for simulating
registers, especially SP. V8 does not handle global variables
efficiently.

This CL reduces global variable accesses by caching the global SP
in a local variable in each function. The local cache is set on
function entry and updated after each call (where the stack could
have moved). Within a function, the SP access will use the local
variable.

Supersedes https://golang.org/cl/173979.

Running on Chrome Version 73.0.3683.103 on darwin/amd64:

name                   old time/op    new time/op     delta
BinaryTree17              15.3s ± 2%      14.5s ± 3%   -5.20%  (p=0.000 n=9+10)
Fannkuch11                8.91s ± 2%      9.48s ± 2%   +6.41%  (p=0.000 n=9+10)
FmtFprintfEmpty           197ns ± 5%      165ns ± 3%  -16.09%  (p=0.000 n=9+8)
FmtFprintfString          354ns ± 8%      325ns ± 7%   -8.33%  (p=0.001 n=10+10)
FmtFprintfInt             400ns ± 4%      368ns ± 6%   -8.01%  (p=0.000 n=10+10)
FmtFprintfIntInt          618ns ± 3%      587ns ± 6%   -4.97%  (p=0.001 n=10+10)
FmtFprintfPrefixedInt     637ns ± 4%      606ns ± 4%   -4.88%  (p=0.000 n=10+10)
FmtFprintfFloat           965ns ± 7%      898ns ± 4%   -6.97%  (p=0.000 n=10+10)
FmtManyArgs              2.34µs ± 1%     2.24µs ± 3%   -4.40%  (p=0.000 n=9+10)
GobDecode                29.8ms ± 3%     28.8ms ± 6%   -3.60%  (p=0.006 n=9+10)
GobEncode                20.5ms ± 8%     17.6ms ± 3%  -14.32%  (p=0.000 n=10+10)
Gzip                      714ms ± 3%      718ms ± 8%     ~     (p=0.971 n=10+10)
Gunzip                    148ms ± 3%      136ms ± 3%   -7.99%  (p=0.000 n=10+9)
HTTPClientServer          219µs ± 3%      215µs ± 4%     ~     (p=0.190 n=10+10)
JSONEncode               35.1ms ± 2%     31.8ms ±13%   -9.52%  (p=0.002 n=10+10)
JSONDecode                220ms ± 3%      207ms ± 5%   -5.87%  (p=0.000 n=10+10)
Mandelbrot200            5.22ms ± 1%     5.11ms ± 4%   -2.11%  (p=0.027 n=8+10)
GoParse                  17.2ms ± 6%     16.1ms ± 5%   -6.63%  (p=0.000 n=10+9)
RegexpMatchEasy0_32       375ns ± 3%      340ns ± 3%   -9.25%  (p=0.000 n=10+10)
RegexpMatchEasy0_1K      2.70µs ± 3%     2.65µs ± 4%     ~     (p=0.118 n=10+10)
RegexpMatchEasy1_32       341ns ± 2%      305ns ± 4%  -10.62%  (p=0.000 n=9+10)
RegexpMatchEasy1_1K      3.20µs ± 3%     2.99µs ± 3%   -6.35%  (p=0.000 n=10+10)
RegexpMatchMedium_32      520ns ± 3%      501ns ± 4%   -3.64%  (p=0.002 n=9+10)
RegexpMatchMedium_1K      145µs ± 7%      128µs ± 3%  -11.57%  (p=0.000 n=9+10)
RegexpMatchHard_32       7.88µs ± 3%     7.01µs ± 5%  -10.97%  (p=0.000 n=10+10)
RegexpMatchHard_1K        237µs ± 5%      207µs ± 4%  -12.71%  (p=0.000 n=9+10)
Revcomp                   2.34s ± 1%      2.31s ± 5%     ~     (p=0.230 n=7+10)
Template                  261ms ± 7%      246ms ± 5%   -5.93%  (p=0.007 n=10+10)
TimeParse                1.47µs ± 3%     1.39µs ± 5%   -5.75%  (p=0.000 n=9+10)
TimeFormat               1.52µs ± 3%     1.43µs ± 4%   -6.42%  (p=0.000 n=8+10)

name                   old speed      new speed       delta
GobDecode              25.7MB/s ± 3%   26.7MB/s ± 5%   +3.77%  (p=0.006 n=9+10)
GobEncode              37.5MB/s ± 8%   43.7MB/s ± 3%  +16.61%  (p=0.000 n=10+10)
Gzip                   27.2MB/s ± 3%   27.0MB/s ± 7%     ~     (p=0.971 n=10+10)
Gunzip                  131MB/s ± 3%    142MB/s ± 5%   +8.07%  (p=0.000 n=10+10)
JSONEncode             55.2MB/s ± 2%   61.2MB/s ±12%  +10.80%  (p=0.002 n=10+10)
JSONDecode             8.84MB/s ± 3%   9.39MB/s ± 5%   +6.28%  (p=0.000 n=10+10)
GoParse                3.37MB/s ± 6%   3.61MB/s ± 5%   +7.09%  (p=0.000 n=10+9)
RegexpMatchEasy0_32    85.3MB/s ± 3%   94.0MB/s ± 3%  +10.20%  (p=0.000 n=10+10)
RegexpMatchEasy0_1K     379MB/s ± 3%    387MB/s ± 4%     ~     (p=0.123 n=10+10)
RegexpMatchEasy1_32    93.9MB/s ± 2%  105.1MB/s ± 4%  +11.96%  (p=0.000 n=9+10)
RegexpMatchEasy1_1K     320MB/s ± 3%    342MB/s ± 3%   +6.79%  (p=0.000 n=10+10)
RegexpMatchMedium_32   1.92MB/s ± 2%   2.00MB/s ± 3%   +3.94%  (p=0.001 n=9+10)
RegexpMatchMedium_1K   7.09MB/s ± 6%   8.01MB/s ± 3%  +13.00%  (p=0.000 n=9+10)
RegexpMatchHard_32     4.06MB/s ± 3%   4.56MB/s ± 5%  +12.38%  (p=0.000 n=10+10)
RegexpMatchHard_1K     4.32MB/s ± 4%   4.96MB/s ± 4%  +14.60%  (p=0.000 n=9+10)
Revcomp                 109MB/s ± 1%    110MB/s ± 5%     ~     (p=0.219 n=7+10)
Template               7.44MB/s ± 8%   7.91MB/s ± 5%   +6.30%  (p=0.007 n=10+10)

Change-Id: I5828cf6b23ce104c02addc2642aba48dd6c48aab
Reviewed-on: https://go-review.googlesource.com/c/go/+/174062
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

* cmd/go/internal/modfetch: fix concurrent read/write race in modfetch

On Windows systems, the failure rate for cmd/go's TestScript/mod_concurrent
is somewhere around 3-10% without this change. With the change, I have yet
to see a failure.

Fixes #31744.

Change-Id: Ib321ebb9556dd8438086cf329dfa083a9e051732
Reviewed-on: https://go-review.googlesource.com/c/go/+/174439
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* encoding/csv: add a Fuzz function

Adds a sample Fuzz test function to package encoding/csv based on
https://github.com/dvyukov/go-fuzz-corpus/blob/master/csv/main.go

Updates #19109
Updates #31309

Change-Id: Ieb0cb6caa1df72dbb7e29df4bdeed0bfa91187d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/174302
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/go: say to confirm import path when it's not found

Fixes #31366.

Change-Id: Ief26f53e7fe94bedb7db79d3d7130c4cdcec4281
Reviewed-on: https://go-review.googlesource.com/c/go/+/174179
Run-TryBot: Jay Conrod <jayconrod@google.com>
Reviewed-by: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* html: add a Fuzz function

Adds a sample Fuzz test function to package html based on
https://github.com/dvyukov/go-fuzz-corpus/blob/master/stdhtml/main.go

Updates #19109
Updates #31309

Change-Id: I8c49fff8f70fc8a8813daf1abf0044752003adbb
Reviewed-on: https://go-review.googlesource.com/c/go/+/174301
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/dist: disable cgo for darwin/386

Fixes #31751

Change-Id: Id002f14557a34accc3597cb1b9a42e838a027da4
Reviewed-on: https://go-review.googlesource.com/c/go/+/174497
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* runtime: implement pthread functions for darwin/arm64

They were not needed when Go only produced binaries with cgo suppport.
Now that Go is about to run self-hosted on iOS we do need these.

Updates #31722

Change-Id: If233aa2b31edc7b1c2dcac68974f9fba0604f9a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/174300
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

* cmd/link: add .go.buildinfo in XCOFF symbol table

.go.buildinfo must be added to the symbol table on AIX. Otherwise, ld
won't be able to handle its relocations.

This patch also make ".data" the default section for all symbols inside
the data segment.

Change-Id: I83ac2bf1050e0ef6ef9c96ff793efd4ddc8e98d7
Reviewed-on: https://go-review.googlesource.com/c/go/+/174298
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* all: add new GOOS=illumos, split out of GOOS=solaris

Like GOOS=android which implies the "linux" build tag, GOOS=illumos
implies the "solaris" build tag. This lets the existing ecosystem of
packages still work on illumos, but still permits packages to start
differentiating between solaris and illumos.

Fixes #20603

Change-Id: I8f4eabf1a66060538dca15d7658c1fbc6c826622
Reviewed-on: https://go-review.googlesource.com/c/go/+/174457
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* runtime: fix data sizes for res_search results

The return values are 32 bit, not 64 bit.

I don't think this would be the cause of any problems, but
it can't hurt to fix it.

Change-Id: Icdd50606360ab9d74070271f9d1721d5fe640bc7
Reviewed-on: https://go-review.googlesource.com/c/go/+/174518
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/go/internal/modcmd: allow mod download without go.mod

Fixes #29522

Change-Id: I48f3a945d24c23c7c7ef5c7f1fe5046b6b2898e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/157937
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>

* all: refer to map elements as elements instead of values

The spec carefully and consistently uses "key" and "element"
as map terminology. The implementation, not so much.

This change attempts to make the implementation consistently
hew to the spec's terminology. Beyond consistency, this has
the advantage of avoid some confusion and naming collisions,
since v and value are very generic and commonly used terms.

I believe that I found all everything, but there are a lot of
non-obvious places for these to hide, and grepping for them is hard.
Hopefully this change changes enough of them that we will start using
elem going forward. Any remaining hidden cases can be removed ad hoc
as they are discovered.

The only externally-facing part of this change is in package reflect,
where there is a minor doc change and a function parameter name change.

Updates #27167

Change-Id: I2f2d78f16c360dc39007b9966d5c2046a29d3701
Reviewed-on: https://go-review.googlesource.com/c/go/+/174523
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* encoding/gob: adding missing fuzz skip to one of the fuzz tests

It's slow & often times out randomly on longtest builders. Not useful.

Fixes #31517

Change-Id: Icedbb0c94fbe43d04e8b47d5785ac61c5e2d8750
Reviewed-on: https://go-review.googlesource.com/c/go/+/174522
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/dist: set the default external linker on platforms without gcc

The go tool already sets -extld to the appropriate compiler. This
CL changes cmd/dist to do the same, to fix bootstrapping on platforms
that only have clang (Android and iOS).

Updates #31722

Change-Id: I8a4fd227f85a768053a8946198eab68bbbdf9ae5
Reviewed-on: https://go-review.googlesource.com/c/go/+/174305
Run-TryBot: Elias Naur <mail@eliasnaur.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/dist: detect GOHOSTARCH on iOS

cmd/dist defaults to GOHOSTARCH=amd64 on darwin because no other
darwin host could build Go. With the upcoming self-hosted iOS
builders, GOHOSTARCH=arm64 is also possible.

Updates #31722

Change-Id: I9af47d9f8c57ea45475ce498acefbfe6bf4815b9
Reviewed-on: https://go-review.googlesource.com/c/go/+/174306
Run-TryBot: Elias Naur <mail@eliasnaur.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/go: derive executable name from package path in 'go run'

Change name of temporary executable on go run . to directory name.
Fixes #31571

Change-Id: I0a0ce74154e76205bb43805c95bd7fb8fd2dfd01
GitHub-Last-Rev: e0964983e18a1d45b55f7098c7489059708c7e5e
GitHub-Pull-Request: golang/go#31614
Reviewed-on: https://go-review.googlesource.com/c/go/+/173297
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

* time: look for zoneinfo.zip in GOROOT

The zoneinfo.zip file will be in the $GOROOT in self-hsoted builds
on iOS.

Updates #31722

Change-Id: I991fae92e3dc50581b099a2d8901aed36ecc7cef
Reviewed-on: https://go-review.googlesource.com/c/go/+/174310
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/go: query modules in parallel

Refactor modload.QueryPackage and modload.QueryPattern to share code.

Fine-tune error reporting and make it consistent between QueryPackage and QueryPattern.

Expand tests for pattern errors.

Update a TODO in modget/get.go and add a test case that demonstrates it.

Updates #26232

Change-Id: I900ca8de338ef9a51b7f85ed93d8bcf837621646
Reviewed-on: https://go-review.googlesource.com/c/go/+/173017
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

* net/http: make Server return 501 for unsupported transfer-encodings

Ensures that our HTTP/1.X Server properly responds
with a 501 Unimplemented as mandated by the spec at
RFC 7230 Section 3.3.1, which says:
    A server that receives a request message with a
    transfer coding it does not understand SHOULD
    respond with 501 (Unimplemented).

Fixes #30710

Change-Id: I096904e6df053cd1e4b551774cc27523ff3d09f6
Reviewed-on: https://go-review.googlesource.com/c/go/+/167017
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/go,cmd/internal/sys,cmd/link: skip Go build ids for externally linked tools

cmd/go already skips build ids on Android where buildmode=pie is
forced. Expand the check to all externally linked tools.

Necessary for self-hosted iOS builds where PIE is not forced but
external linking is.

Updates #31722

Change-Id: Iad796a9411a37eb0c44d365b70a3c5907537e461
Reviewed-on: https://go-review.googlesource.com/c/go/+/174307
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

* cmd/go/internal/modfetch/codehost: disable fetch of server-resolved commit hash

We cannot rely on the server to filter out the refs we don't want
(we only want refs/heads/* and refs/tags/*), so do not give it
the full hash.

Fixes #31191.

Change-Id: If1208c35954228aa6e8734f8d5f1725d0ec79c87
Reviewed-on: https://go-review.googlesource.com/c/go/+/174517
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/compile: remove dynamic entry handling from sinit/maplit

The order pass now handles all the dynamic entries.

Update #26552

Followup to CL 174417

Change-Id: Ie924cadb0e0ba36c423868f654f13040100b44c6
Reviewed-on: https://go-review.googlesource.com/c/go/+/174498
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

* os: fix tests on self-hosted Go builds

Updates #31722

Change-Id: I467bb2539f993fad642abf96388a58a263fbe007
Reviewed-on: https://go-review.googlesource.com/c/go/+/174311
Run-TryBot: Elias Naur <mail@eliasnaur.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/asm: reject BSWAPW on amd64

Since BSWAP operation on 16-bit registers is undefined,
forbid the usage of BSWAPW. Users should rely on XCHGB instead.

This behavior is consistent with what GAS does.

Fixes #29167

Change-Id: I3b31e3dd2acfd039f7564a1c17e6068617bcde8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/174312
Run-TryBot: Iskander Sharipov <quasilyte@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/compile: fix line numbers for index panics

In the statement x = a[i], the index panic should appear to come from
the line number of the '['. Previous to this CL we sometimes used the
line number of the '=' instead.

Fixes #29504

Change-Id: Ie718fd303c1ac2aee33e88d52c9ba9bcf220dea1
Reviewed-on: https://go-review.googlesource.com/c/go/+/174617
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/compile: add signed divisibility rules

"Division by invariant integers using multiplication" paper
by Granlund and Montgomery contains a method for directly computing
divisibility (x%c == 0 for c constant) by means of the modular inverse.
The method is further elaborated in "Hacker's Delight" by Warren Section 10-17

This general rule can compute divisibilty by one multiplication, and add
and a compare for odd divisors and an additional rotate for even divisors.

To apply the divisibility rule, we must take into account
the rules to rewrite x%c = x-((x/c)*c) and (x/c) for c constant on the first
optimization pass "opt".  This complicates the matching as we want to match
only in the cases where the result of (x/c) is not also needed.
So, we must match on the expanded form of (x/c) in the expression x == c*(x/c)
in the "late opt" pass after common subexpresion elimination.

Note, that if there is an intermediate opt pass introduced in the future we
could simplify these rules by delaying the magic division rewrite to "late opt"
and matching directly on (x/c) in the intermediate opt pass.

On amd64, the divisibility check is 30-45% faster.

name                     old time/op  new time/op  delta`
DivisiblePow2constI64-4  0.83ns ± 1%  0.82ns ± 0%     ~     (p=0.079 n=5+4)
DivisibleconstI64-4      2.68ns ± 1%  1.87ns ± 0%  -30.33%  (p=0.000 n=5+4)
DivisibleWDivconstI64-4  2.69ns ± 1%  2.71ns ± 3%     ~     (p=1.000 n=5+5)
DivisiblePow2constI32-4  1.15ns ± 1%  1.15ns ± 0%     ~     (p=0.238 n=5+4)
DivisibleconstI32-4      2.24ns ± 1%  1.20ns ± 0%  -46.48%  (p=0.016 n=5+4)
DivisibleWDivconstI32-4  2.27ns ± 1%  2.27ns ± 1%     ~     (p=0.683 n=5+5)
DivisiblePow2constI16-4  0.81ns ± 1%  0.82ns ± 1%     ~     (p=0.135 n=5+5)
DivisibleconstI16-4      2.11ns ± 2%  1.20ns ± 1%  -42.99%  (p=0.008 n=5+5)
DivisibleWDivconstI16-4  2.23ns ± 0%  2.27ns ± 2%   +1.79%  (p=0.029 n=4+4)
DivisiblePow2constI8-4   0.81ns ± 1%  0.81ns ± 1%     ~     (p=0.286 n=5+5)
DivisibleconstI8-4       2.13ns ± 3%  1.19ns ± 1%  -43.84%  (p=0.008 n=5+5)
DivisibleWDivconstI8-4   2.23ns ± 1%  2.25ns ± 1%     ~     (p=0.183 n=5+5)

Fixes #30282
Fixes #15806

Change-Id: Id20d78263a4fdfe0509229ae4dfa2fede83fc1d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/173998
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

* cmd/go: make get -u upgrade only modules providing packages

Currently, 'go get -u' upgrades modules matching command line
arguments and any modules they transitively require. 'go get -u' with
no positional arguments upgrades all modules transitively required by
the main module. This usually adds a large number of indirect
requirements, which is surprising to users.

With this change, 'go get' will load packages specified by
its arguments using a similar process to other commands
('go build', etc). Only modules providing packages will be upgraded.

'go get -u' now upgrades modules providing packages transitively
imported by the command-line arguments. 'go get -u' without arguments
will only upgrade modules needed by the package in the current
directory.

'go get -m' will load all packages within a module. 'go get -m -u'
without arguments will upgrade modules needed by the main module. It
is equivalent to 'go get -u all'. Neither command will upgrade modules
that are required but not used.

Note that 'go get -m' and 'go get -d' both download modules in order
to load packages.

Fixes #26902

Change-Id: I2bad686b3ca8c9de985a81fb42b16a36bb4cc3ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/174099
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

* syscall: on wasm, do not use typed array asynchronously

The underlying buffer of a typed array becomes invalid as soon as we
grow the WebAssembly memory, which can happen at any time while Go code
runs. This is a known limitation, see https://golang.org/cl/155778.

As a consequence, using a typed array with one of the asynchronous
read/write operations of Node.js' fs module is dangerous, since it may
become invalid while the asynchronous operation has not finished yet.
The result of this situation is most likely undefined.

I am not aware of any nice solution to this issue, so this change adds
a workaround of using an additional typed array which is not backed by
WebAssembly memory and copying the bytes between the two typed arrays.

Maybe WebAssembly will come up with a better solution in the future.

Fixes #31702.

Change-Id: Iafc2a0fa03c81db414520bd45a1a17c00080b61e
Reviewed-on: https://go-review.googlesource.com/c/go/+/174304
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

* net/http: add Transport.ReadBufferSize and WriteBufferSize

Previously transport was using the hardcoded bufio.defaultBufSize
(4096), limiting throughput and increasing cpu usage when uploading or
downloading large files.

Add options to allow users to configure the buffer sizes as needed.

I tested the maximum benefit of this change by uploading data from
/dev/zero to a server discarding the bytes. Here is an example upload
using the default buffer size:

$ time ./upload 10 https://localhost:8000/
Uploaded 10.00g in 25.13 seconds (407.49m/s)

real	0m25.135s
user	0m5.167s
sys	0m11.643s

With this change, using 128k buffer size:

$ time ./upload 10 https://localhost:8000/
Uploaded 10.00g in 7.93 seconds (1291.51m/s)

real	0m7.935s
user	0m4.517s
sys	0m2.603s

In real world usage the difference will be smaller, depending on the
local and remote storage and the network.

See https://github.com/nirs/http-bench for more info.

Fixes #22618

Change-Id: Iac99ed839c7b95d6dc66602ba8fe1fc5b500c47c
Reviewed-on: https://go-review.googlesource.com/c/go/+/76410
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* net/http: make Transport.MaxConnsPerHost work for HTTP/2

Treat HTTP/2 connections as an ongoing persistent connection. When we
are told there is no cached connections, cleanup the associated
connection and host connection count.

Fixes #27753

Change-Id: I6b7bd915fc7819617cb5d3b35e46e225c75eda29
Reviewed-on: https://go-review.googlesource.com/c/go/+/140357
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* internal/cpu: add detection for the new ECDSA and EDDSA capabilities on s390x

This CL will check for the Message-Security-Assist Extension 9 facility
which enables the KDSA instruction.

Change-Id: I659aac09726e0999ec652ef1f5983072c8131a48
Reviewed-on: https://go-review.googlesource.com/c/go/+/174529
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* net: set DNSError.IsTemporary from addrinfoErrno errors

Today it is not possible (AFAICT) to detect if a DNSError if of type EAI_AGAIN, i.e. if it is something temporary that should be retried. This information is available inside addrinfoErrno but when the DNSError is created this information is lost.

This PR fixes this so that the addinfoErrno.Temporary information is added to DNSError as well. With that a user who gets a DNSError can check now is its a temporary error (for errors that resulted from a addrinfoErrno this is EAI_AGAIN).

Change-Id: I64badb2ebd904e41fc2e0755416f7f32560534d8
GitHub-Last-Rev: ced7238a6597039fb23f36f372bd1cf33d60d4a6
GitHub-Pull-Request: golang/go#31676
Reviewed-on: https://go-review.googlesource.com/c/go/+/174557
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* os,time: fix tests on iOS

When fixing tests for for self-hosted iOS builds, I
broke hosted builds.

Updates #31722

Change-Id: Id4e7d234fbd86cb2d29d320d75f4441efd663d12
Reviewed-on: https://go-review.googlesource.com/c/go/+/174698
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* test: enable more memcombine tests for ppc64le

This enables more of the testcases in memcombine for ppc64le,
and adds more detail to some existing.

Change-Id: Ic522a1175bed682b546909c96f9ea758f8db247c
Reviewed-on: https://go-review.googlesource.com/c/go/+/174737
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* runtime: change the span allocation policy to first-fit

This change modifies the treap implementation to be address-ordered
instead of size-ordered, and further augments it so it may be used for
allocation. It then modifies the find method to implement a first-fit
allocation policy.

This change to the treap implementation consequently makes it so that
spans are scavenged in highest-address-first order without any
additional changes to the scavenging code. Because the treap itself is
now address ordered, and the scavenging code iterates over it in
reverse, the highest address is now chosen instead of the largest span.

This change also renames the now wrongly-named "scavengeLargest" method
on mheap to just "scavengeLocked" and also fixes up logic in that method
which made assumptions about size.

For #30333.

Change-Id: I94b6f3209211cc1bfdc8cdaea04152a232cfbbb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/164101
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

* go/internal/gccgoimporter: skip new test with aliases with old gccgo

Add the issue31540 test to the list of tests that needs to be skipped
with old copies of gccgo. Along the way, add an explicit field to the
importer test struct that can be used to tag the test (as opposed to
having special cases by name in the test routine), so as to make it
easier to remember to tag testcases correctly.

Fixes #31764.

Change-Id: Ib9d98fea2df8ce0b51e5a886fb2c4acd6db490ff
Reviewed-on: https://go-review.googlesource.com/c/go/+/174738
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/compile/internal/ppc64: improve naming for ginsnop2

This is a follow up from a review comment at the end of the last
Go release, to provide a more meaningful name for ginsnop2.

Updates #30475

Change-Id: Ice9efd763bf2204a9e8c55ae230d3e8a80210108
Reviewed-on: https://go-review.googlesource.com/c/go/+/174757
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

* index/suffixarray: add 32-bit implementation

The original index/suffixarray used 32-bit ints on 64-bit machines,
because that's what 'int' meant in Go at the time. When we changed
the meaning of int, that doubled the space overhead of suffix arrays
for all uses, even though the vast majority of them describe less
than 2 GB of text.

The space overhead of a suffix array compared to the text is not
insignificant: there's a big difference for many uses between 4X and 8X.

This CL adjusts names in qsufsort.go so that a global search and
replace s/32/64/g produces a working 64-bit implementation,
and then it modifies suffixarray.go to choose between the 32-bit
and 64-bit implementation as appropriate depending on the input size.
The 64-bit implementation is generated by 'go generate'.

This CL also restructures the benchmarks, to test different
input sizes, different input texts, and 32-bit vs 64-bit.

The serialized form uses varint-encoded numbers and is unchanged,
so on-disk suffix arrays written by older versions of Go will be
readable by this version, and vice versa.

The 32-bit version runs a up to 17% faster than the 64-bit version
on real inputs, but more importantly it uses 50% less memory.

I have a followup CL that also implements a faster algorithm
on top of these improvements, but these are a good first step.

name                                  64-bit speed   32-bit speed    delta
New/text=opticks/size=100K/bits=*-12  4.44MB/s ± 0%  4.64MB/s ± 0%   +4.41%  (p=0.008 n=5+5)
New/text=opticks/size=500K/bits=*-12  3.70MB/s ± 1%  3.82MB/s ± 0%   +3.30%  (p=0.008 n=5+5)
New/text=go/size=100K/bits=*-12       4.40MB/s ± 0%  4.61MB/s ± 0%   +4.82%  (p=0.008 n=5+5)
New/text=go/size=500K/bits=*-12       3.66MB/s ± 0%  3.77MB/s ± 0%   +3.01%  (p=0.016 n=4+5)
New/text=go/size=1M/bits=*-12         3.29MB/s ± 0%  3.55MB/s ± 0%   +7.90%  (p=0.016 n=5+4)
New/text=go/size=5M/bits=*-12         2.25MB/s ± 1%  2.65MB/s ± 0%  +17.81%  (p=0.008 n=5+5)
New/text=go/size=10M/bits=*-12        1.82MB/s ± 0%  2.09MB/s ± 1%  +14.36%  (p=0.008 n=5+5)
New/text=go/size=50M/bits=*-12        1.35MB/s ± 0%  1.51MB/s ± 1%  +12.33%  (p=0.008 n=5+5)
New/text=zero/size=100K/bits=*-12     3.42MB/s ± 0%  3.32MB/s ± 0%   -2.74%  (p=0.000 n=5+4)
New/text=zero/size=500K/bits=*-12     3.00MB/s ± 1%  2.97MB/s ± 0%   -1.13%  (p=0.016 n=5+4)
New/text=zero/size=1M/bits=*-12       2.81MB/s ± 0%  2.78MB/s ± 2%     ~     (p=0.167 n=5+5)
New/text=zero/size=5M/bits=*-12       2.46MB/s ± 0%  2.53MB/s ± 0%   +3.18%  (p=0.008 n=5+5)
New/text=zero/size=10M/bits=*-12      2.35MB/s ± 0%  2.42MB/s ± 0%   +2.98%  (p=0.016 n=4+5)
New/text=zero/size=50M/bits=*-12      2.12MB/s ± 0%  2.18MB/s ± 0%   +3.02%  (p=0.008 n=5+5)
New/text=rand/size=100K/bits=*-12     6.98MB/s ± 0%  7.22MB/s ± 0%   +3.38%  (p=0.016 n=4+5)
New/text=rand/size=500K/bits=*-12     5.53MB/s ± 0%  5.64MB/s ± 0%   +1.92%  (p=0.008 n=5+5)
New/text=rand/size=1M/bits=*-12       4.62MB/s ± 1%  5.06MB/s ± 0%   +9.61%  (p=0.008 n=5+5)
New/text=rand/size=5M/bits=*-12       3.09MB/s ± 0%  3.43MB/s ± 0%  +10.94%  (p=0.016 n=4+5)
New/text=rand/size=10M/bits=*-12      2.68MB/s ± 0%  2.95MB/s ± 0%  +10.39%  (p=0.008 n=5+5)
New/text=rand/size=50M/bits=*-12      1.92MB/s ± 0%  2.06MB/s ± 1%   +7.41%  (p=0.008 n=5+5)
SaveRestore/bits=*-12                  243MB/s ± 1%   259MB/s ± 0%   +6.68%  (p=0.000 n=9+10)

name                               64-bit alloc/op  32-bit alloc/op  delta
New/text=opticks/size=100K/bits=*-12    1.62MB ± 0%    0.81MB ± 0%  -50.00%  (p=0.000 n=5+4)
New/text=opticks/size=500K/bits=*-12    8.07MB ± 0%    4.04MB ± 0%  -49.89%  (p=0.008 n=5+5)
New/text=go/size=100K/bits=*-12         1.62MB ± 0%    0.81MB ± 0%  -50.00%  (p=0.008 n=5+5)
New/text=go/size=500K/bits=*-12         8.07MB ± 0%    4.04MB ± 0%  -49.89%  (p=0.029 n=4+4)
New/text=go/size=1M/bits=*-12           16.1MB ± 0%     8.1MB ± 0%  -49.95%  (p=0.008 n=5+5)
New/text=go/size=5M/bits=*-12           80.3MB ± 0%    40.2MB ± 0%     ~     (p=0.079 n=4+5)
New/text=go/size=10M/bits=*-12           160MB ± 0%      80MB ± 0%  -50.00%  (p=0.008 n=5+5)
New/text=go/size=50M/bits=*-12           805MB ± 0%     402MB ± 0%  -50.06%  (p=0.029 n=4+4)
New/text=zero/size=100K/bits=*-12       3.02MB ± 0%    1.46MB ± 0%     ~     (p=0.079 n=4+5)
New/text=zero/size=500K/bits=*-12       19.7MB ± 0%     8.7MB ± 0%  -55.98%  (p=0.008 n=5+5)
New/text=zero/size=1M/bits=*-12         39.0MB ± 0%    19.7MB ± 0%  -49.60%  (p=0.000 n=5+4)
New/text=zero/size=5M/bits=*-12          169MB ± 0%      85MB ± 0%  -49.46%  (p=0.029 n=4+4)
New/text=zero/size=10M/bits=*-12         333MB ± 0%     169MB ± 0%  -49.43%  (p=0.000 n=5+4)
New/text=zero/size=50M/bits=*-12        1.63GB ± 0%    0.74GB ± 0%  -54.61%  (p=0.008 n=5+5)
New/text=rand/size=100K/bits=*-12       1.61MB ± 0%    0.81MB ± 0%  -50.00%  (p=0.000 n=5+4)
New/text=rand/size=500K/bits=*-12       8.07MB ± 0%    4.04MB ± 0%  -49.89%  (p=0.000 n=5+4)
New/text=rand/size=1M/bits=*-12         16.1MB ± 0%     8.1MB ± 0%  -49.95%  (p=0.029 n=4+4)
New/text=rand/size=5M/bits=*-12         80.7MB ± 0%    40.3MB ± 0%  -50.06%  (p=0.008 n=5+5)
New/text=rand/size=10M/bits=*-12         161MB ± 0%      81MB ± 0%  -50.03%  (p=0.008 n=5+5)
New/text=rand/size=50M/bits=*-12         806MB ± 0%     403MB ± 0%  -50.00%  (p=0.016 n=4+5)
SaveRestore/bits=*-12                   9.47MB ± 0%    5.28MB ± 0%  -44.29%  (p=0.000 n=9+8)

https://perf.golang.org/search?q=upload:20190126.1+|+bits:64+vs+bits:32

Fixes #6816.

Change-Id: Ied2fbea519a202ecc43719debcd233344ce38847
Reviewed-on: https://go-review.googlesource.com/c/go/+/174097
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* runtime: look for idle p to run current goroutine when switching to GC or traceReader

This repairs one of the several causes of pauses uncovered
by a GC microbenchmark.  A pause can occur when a goroutine's
quantum expires "at the same time" a GC is needed.  The
current M switches to running a GC worker, which means that
the amount of available work has expanded by one.  The GC
worker, however, does not call ready, and does not itself
conditionally wake a P (a "normal" thread would do this).

This is also true if M switches to a traceReader.

This is problem 4 in this list:
https://github.com/golang/go/issues/27732#issuecomment-423301252

Updates #27732.

Change-Id: I6905365cac8504cde6faab2420f4421536551f0b
Reviewed-on: https://go-review.googlesource.com/c/go/+/146817
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

* cmd/go/internal/modfetch/codehost: fix pseudoversions for non-semver tags and tags on other branches

Pseudoversion determination depends in part on the results from gitRepo.RecentTag, which currently invokes:

git describe --first-parent --always --abbrev=0 --match <prefix>v[0-9]*.[0-9]*.[0-9]* --tags <rev>

The comment at https://github.com/golang/go/issues/27171#issuecomment-470134255 describes some problems with the current approach.

One problem is Docker and other repos can have tags that are not valid semver tags but that still match a glob pattern of v[0-9]*.[0-9]*.[0-9]* which are found by 'git describe' but then rejected by cmd/go, and hence those repos currently can end up with v0.0.0 pseudoversions instead of finding a proper semver tag to use as input to building a pseudoversion  (when then causes problems when the v0.0.0 pseudoversion is fed into MVS). An example problematic tag is a date-based tag such as 'v18.06.16', which matches the glob pattern, but is not a valid semver tag (due to the leading 0 in '06').

Issues #31673, #31287, and #27171 also describe problems where the '--first-parent' argument to 'git describe' cause the current approach to miss relevant semver tags that were created on a separate branch and then subsequently merged to master.

In #27171, Bryan described the base tag that is supposed to be used for pseudoversions as:

"It is intended to be the semantically-latest tag that appears on any commit that is a (transitive) parent of the commit with the given hash, regardless of branches. (The pseudo-version is supposed to sort after every version — tagged or otherwise — that came before it, but before the next tag that a human might plausibly want to apply to the branch.)"

This CL solves the glob problem and tags-on-other-branches problem more directly than the current approach: this CL gets the full list of tags that have been merged into the specific revision of interest, and then sorts and filters the results in cmd/go to select the semantically-latest valid semver tag.

Fixes #31673
Fixes #31287
Updates #27171

Change-Id: I7c3e6b46b2b21dd60562cf2893b6bd2afaae61d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/174061
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

* cmd/go/internal/get: fix strayed verbose output on stdout

Fixes #31768

Change-Id: I3cc0ebc4be34d7c2d2d4fd655bfd0c2515ff3021
Reviewed-on: https://go-review.googlesource.com/c/go/+/174739
Reviewed-by: Jay Conrod <jayconrod@google.com>
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

* cmd/dist: only build exec wrappers when cross compiling

Updates #31722

Change-Id: Ib44b46e628e364fff6eacda2b26541db2f0a4261
Reviewed-on: https://go-review.googlesource.com/c/go/+/174701
Run-TryBot: Elias Naur <mail@eliasnaur.com>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* misc/cgo/testcarchive: skip TestExtar on self-hosted iOS

iOS cannot (directly) run shell scripts.

Updates #31722

Change-Id: I69473e9339c50a77338d391c73b4e146bce3fa89
Reviewed-on: https://go-review.googlesource.com/c/go/+/174700
Run-TryBot: Elias Naur <mail@eliasnaur.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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* strings, bytes: add ToValidUTF8

The newly added functions create a copy of their input with all bytes in
invalid UTF-8 byte sequences mapped to the UTF-8 byte sequence
given as replacement parameter.

Fixes #25805

Change-Id: Iaf65f65b40c0581c6bb000f1590408d6628321d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/142003
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/go: sort vendor/modules.txt package lists

Right now they are in a deterministic order
but one that depends on the shape of the import graph.
Sort them instead.

Change-Id: Ia0c076a0d6677a511e52acf01f38353e9895dec2
Reviewed-on: https://go-review.googlesource.com/c/go/+/174527
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
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* cmd/compile: fix maplit init panics for dynamic entry

golang.org/cl/174498 removes dynamic map entry handling in maplit, by
filtering the static entry only. It panics if it see a dynamic entry.
It relies on order to remove all dynamic entries.

But after recursively call order on the statics, some static entries
become dynamic, e.g OCONVIFACE node:

	type i interface {
		j()
	}
	type s struct{}

	func (s) j() {}

	type foo map[string]i

	var f = foo{
		"1": s{},
	}

To fix it, we recursively call order on each static entry, if it changed
to dynamic, put entry to dynamic then.

Fixes #31777

Change-Id: I1004190ac8f2d1eaa4beb6beab989db74099b025
Reviewed-on: https://go-review.googlesource.com/c/go/+/174777
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
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* cmd/go/internal/web: fix log message

The web package is now used for proxy fetches, so its logs shouldn't
start with "Parsing meta tags".

Change-Id: I22a7dce09e3a681544ee4b860f93c63336e547ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/174740
Run-TryBot: Heschi Kreinick <heschi@google.com>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/compile: disable Go1.13 language features for -lang=go1.12 and below

Fixes   #31747.
Updates #19308.
Updates #12711.
Updates #29008.
Updates #28493.
Updates #19113.

Change-Id: I76d2fdbc7698cc4e0f31b7ae24cbb4d28afbb6a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/174897
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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* errors: fix comment referencing the Wrapper interface

The Unwrap function performs a type assertion looking for the Wrapper
interface. The method of that interface is called Unwrap but the
interface itself is called Wrapper.

Change-Id: Ie3bf296f93b773d36015bcab2a0e6585d39783c7
GitHub-Last-Rev: 32b1a0c2f8bf8f3eaebf6de252571d82313e86e0
GitHub-Pull-Request: golang/go#31794
Reviewed-on: https://go-review.googlesource.com/c/go/+/174917
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* doc/go1.13: start doc, note macOS, FreeBSD deprecations

For #23011.
For #27619.

Change-Id: Id1f280993ecdfb07a7420926ca1c0f5b7872afbb
Reviewed-on: https://go-review.googlesource.com/c/go/+/174521
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/compile: remove outdate TODO in inl.go

Mid-stack inlining is enable now, see #19348, but we still can not
remove the special case for runtime.heapBits.nextArena, because
runtime.heapBits.next is too complex to be inlined
(cost 96 exceeds budget 80).

Change-Id: I04ea86509074afdc83a3f70d68b8a1a8829763d1
Reviewed-on: https://go-review.googlesource.com/c/go/+/174839
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/go: make modconv test more robust

Change-Id: I3e75201c56779eda1bcd725691c72d384da56f73
Reviewed-on: https://go-review.googlesource.com/c/go/+/174840
Run-TryBot: Baokun Lee <nototon@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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* cmd/go/internal/modload: make 'list -u' consider current pseudoversion

As pointed out by thepudds in #30634, the 'list -u' documentation states that the current version should be considered for upgrade:
The -u flag adds information about available upgrades. When the latest version of a given module is newer than the current one, list -u sets the Module's Update field to information about the newer module.

In go 1.12.4 (and current tip), an older version will be suggested as upgrade to a newer pseudo version.

Updates: #30634

Change-Id: If2c8887198884b8e7ccb3a604908065aa1f1878a
Reviewed-on: https://go-review.googlesource.com/c/go/+/174206
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

* cmd/dist: don't generate exec wrappers for compatible cross compiles

This change will allow android/arm64 hosts to build for android/arm,
and likewise for iOS.

Updates #31722

Change-Id: Id410bd112abbab585ebb13b61fe4d3a38a1a81fb
Reviewed-on: https://go-review.googlesource.com/c/go/+/174705
Run-TryBot: Elias Naur <mail@eliasnaur.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* cmd/link: support PIE mode with internal link on linux arm64

This CL improves internal link to provide basic support for cgo and PIE:
1, add support for GOT, PLT and GOTPLT.
2, add support for following ELF relocation types which have been used by std
   packages:
     R_AARCH64_ADR_GOT_PAGE
     R_AARCH64_LD64_GOT_LO12_NC
     R_AARCH64_ADR_PREL_PG_HI21
     R_AARCH64_ADD_ABS_LO12_NC
     R_AARCH64_LDST8_ABS_LO12_NC
     R_AARCH64_LDST32_ABS_LO12_NC
     R_AARCH64_LDST64_ABS_LO12_NC
     R_AARCH64_JUMP26
     R_AARCH64_ABS64
     R_AARCH64_PREL32
     R_AARCH64_PREL64

With this change, Go toolchain can be built in internal linking mode, and
pure Go programs can be built with PIE mode in internal linking mode on arm64.

Updates #10373
The prototype of this CL is contributed by Wei Xiao <wei.xiao@arm.com>

Change-Id: I2253923c69e855fd1524d54def309a961dce6247
Reviewed-on: https://go-review.googlesource.com/c/go/+/163579
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>

* sort: simplify bootstrap

We compile package sort as part of the compiler bootstrap,
to make sure the compiler uses a consistent sort algorithm
no matter what version of Go it is compiled against.
(This matters for elements that compare "equal" but are distinguishab…
@gopherbot
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@gopherbot gopherbot commented Jun 27, 2019

Change https://golang.org/cl/184080 mentions this issue: text/scanner: remove AllowDigitSeparator flag again

gopherbot pushed a commit that referenced this issue Jun 27, 2019
The scanner was changed to accept the new Go number literal syntax
of which separators are a part. Making them opt-in is inconsistent
with the rest of the changes. For comparison, the strconv package
also accepts the new number literals including separators with the
various conversion routines, if no explicit number base is given.

Updates #28493.

Change-Id: Ifaae2225a9565364610813658bfe692901dd3ccd
Reviewed-on: https://go-review.googlesource.com/c/go/+/184080
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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@eacp
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@eacp eacp commented Jun 29, 2019

This would reduce probability of success when grepping code for a constant (grep -Rnw 100000 .), which may lead to wrong conclusions by those analyzing the codebase in a hurry.

Well thats a fair point. I have done that in some JS programs

@gopherbot
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@gopherbot gopherbot commented Aug 10, 2019

Change https://golang.org/cl/189718 mentions this issue: compiler: support new numeric literal syntax

gopherbot pushed a commit to golang/gofrontend that referenced this issue Aug 17, 2019
Support 0b, 0o, and hex floats.

Tested against test/literal2.go in the gc repo.

Updates golang/go#12711
Updates golang/go#19308
Updates golang/go#28493
Updates golang/go#29008

Change-Id: I2ab01255f529880a2bd8603107e3e1ae03a7a3e5
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/189718
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
jpf91 pushed a commit to D-Programming-GDC/gcc that referenced this issue Aug 18, 2019
    
    Support 0b, 0o, and hex floats.
    
    Tested against test/literal2.go in the gc repo.
    
    Updates golang/go#12711
    Updates golang/go#19308
    Updates golang/go#28493
    Updates golang/go#29008
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/189718


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@274614 138bc75d-0d04-0410-961f-82ee72b054a4
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