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  1. 18 Sep, 2019 18 commits
  3. 17 Sep, 2019 12 commits
  5. 16 Sep, 2019 10 commits
    • Matthew Dempsky's avatar
      cmd/compile: major refactoring of switch walking · 8f3d9855
      Matthew Dempsky authored 
      There are a lot of complexities to handling switches efficiently:

1. Order matters for expression switches with non-constant cases and
for type expressions with interface types. We have to respect
side-effects, and we also can't allow later cases to accidentally take
precedence over earlier cases.

2. For runs of integers, floats, and string constants in expression
switches or runs of concrete types in type switches, we want to emit
efficient binary searches.

3. For runs of consecutive integers in expression switches, we want to
collapse them into range comparisons.

4. For binary searches of strings, we want to compare by length first,
because that's more efficient and we don't need to respect any
particular ordering.

5. For "switch true { ... }" and "switch false { ... }", we want to
optimize "case x:" as simply "if x" or "if !x", respectively, unless x
is interface-typed.

The current swt.go code reflects how these constraints have been
incrementally added over time, with each of them being handled ad
hocly in different parts of the code. Also, the existing code tries
very hard to reuse logic between expression and type switches, even
though the similarities are very superficial.

This CL rewrites switch handling to better abstract away the logic
involved in constructing the binary searches. In particular, it's
intended to make further optimizations to switch dispatch much easier.

It also eliminates the need for both OXCASE and OCASE ops, and a
subsequent CL can collapse the two.

Passes toolstash-check.

Change-Id: Ifcd1e56f81f858117a412971d82e98abe7c4481f
Reviewed-on: https://go-review.googlesource.com/c/go/+/194660
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarKeith Randall <khr@golang.org>
      8f3d9855
    • Matthew Dempsky's avatar
      test: add test coverage for type-switch hash collisions · 115e4c9c
      Matthew Dempsky authored 
      This CL expands the test for #29612 to check that type switches also
work correctly when type hashes collide.

Change-Id: Ia153743e6ea0736c1a33191acfe4d8ba890be527
Reviewed-on: https://go-review.googlesource.com/c/go/+/195782
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: default avatarKeith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      115e4c9c
    • Lucas Bremgartner's avatar
      encoding/json: validate strings when decoding into Number · c1000c50
      Lucas Bremgartner authored 
      Unmarshaling a string into a json.Number should first check that the string is a valid Number.
If not, we should fail without decoding it.

Fixes #14702

Change-Id: I286178e93df74ad63c0a852c3f3489577072cf47
GitHub-Last-Rev: fe69bb68eed06d056639f440d2daf4bb7c99013b
GitHub-Pull-Request: golang/go#34272
Reviewed-on: https://go-review.googlesource.com/c/go/+/195045Reviewed-by: default avatarDaniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      c1000c50
    • Daniel Martí's avatar
      cmd/compiler: skip some go/printer work in rulegen · 0e0bff84
      Daniel Martí authored 
      We use go/format on the final output, so don't bother with the added
tabwriter work to align comments when using go/printer.

	name     old time/op         new time/op         delta
	Rulegen          2.53s ± 2%          2.48s ± 1%  -2.20%  (p=0.032 n=5+5)

	name     old user-time/op    new user-time/op    delta
	Rulegen          11.2s ± 1%          10.8s ± 0%  -3.72%  (p=0.008 n=5+5)

	name     old sys-time/op     new sys-time/op     delta
	Rulegen          218ms ±17%          207ms ±19%    ~     (p=0.548 n=5+5)

	name     old peak-RSS-bytes  new peak-RSS-bytes  delta
	Rulegen          184MB ± 3%          175MB ± 4%    ~     (p=0.056 n=5+5)

Change-Id: I53bad2ab15cace67415f2171fffcd13ed596e62b
Reviewed-on: https://go-review.googlesource.com/c/go/+/195219
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: default avatarBrad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      0e0bff84
    • Daniel Martí's avatar
      cmd/compile: parallelize another big chunk of rulegen · 357e8f83
      Daniel Martí authored 
      rulegen has a sanity check that ensures all the arch-specific opcodes
are handled by each of the gen files.

This is an expensive chunk of work, particularly since there are a lot
of opcodes in total, and each one of them compiles and runs a regular
expression.

Parallelize that for each architecture, which greatly speeds up 'go run
*.go' on my laptop with four real CPU cores.

	name     old time/op         new time/op         delta
	Rulegen          3.39s ± 1%          2.53s ± 2%  -25.34%  (p=0.008 n=5+5)

	name     old user-time/op    new user-time/op    delta
	Rulegen          10.6s ± 1%          11.2s ± 1%   +6.09%  (p=0.008 n=5+5)

	name     old sys-time/op     new sys-time/op     delta
	Rulegen          201ms ± 7%          218ms ±17%     ~     (p=0.548 n=5+5)

	name     old peak-RSS-bytes  new peak-RSS-bytes  delta
	Rulegen          182MB ± 3%          184MB ± 3%     ~     (p=0.690 n=5+5)

Change-Id: Iec538ed0fa7eb867eeeeaab3da1e2615ce32cbb9
Reviewed-on: https://go-review.googlesource.com/c/go/+/195218
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarKeith Randall <khr@golang.org>
      357e8f83
    • Jay Conrod's avatar
      cmd/go: don't split internal test main packages twice · 4d18a7ce
      Jay Conrod authored 
      Fixes #34321

Change-Id: Ia6253038c525089e20a1da64a2c5c9dcc57edd74
Reviewed-on: https://go-review.googlesource.com/c/go/+/195677
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarBryan C. Mills <bcmills@google.com>
      4d18a7ce
    • Matthew Dempsky's avatar
      cmd/compile: require -lang=go1.14 for overlapping interfaces · 7f907b9c
      Matthew Dempsky authored 
      Support for overlapping interfaces is a new (proposed) Go language
feature to be supported in Go 1.14, so it shouldn't be supported under
-lang=go1.13 or earlier.

Fixes #34329.

Change-Id: I5fea5716b7d135476980bc40b4f6e8c611b67735
Reviewed-on: https://go-review.googlesource.com/c/go/+/195678
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarRobert Griesemer <gri@golang.org>
      7f907b9c
    • Alberto Donizetti's avatar
      Revert "test/codegen: document -all_codegen option in README" · c2facbe9
      Alberto Donizetti authored 
      This reverts CL 192101.

Reason for revert: The same paragraph was added 2 weeks ago
(look a few lines above)

Change-Id: I05efb2631d7b4966f66493f178f2a649c715a3cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/195637Reviewed-by: default avatarCherry Zhang <cherryyz@google.com>
      c2facbe9
    • Jay Conrod's avatar
      cmd/go: don't include package dir in cache key when -trimpath is set · aa680c0c
      Jay Conrod authored 
      The '-trimpath' flag tells 'go build' to trim any paths from the
output files that are tied to the current workspace or toolchain. When
this flag is set, we do not need to include the package directory in
the text hashed to construct the action ID for each package.

Fixes #33772

Change-Id: I20b902d2f58019709b15864ca79aa0d9255ae707
Reviewed-on: https://go-review.googlesource.com/c/go/+/195318
Run-TryBot: Jay Conrod <jayconrod@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarBryan C. Mills <bcmills@google.com>
      aa680c0c
    • Matthew Dempsky's avatar
      cmd/compile: trim function name prefix from escape diagnostics · 606019cb
      Matthew Dempsky authored 
      This information is redundant with the position information already
provided. Also, no other -m diagnostics print out function name.

While here, report parameter leak diagnostics against the parameter
declaration position rather than the function, and use Warnl for
"moved to heap" messages.

Test cases updated programmatically by removing the first word from
every "no match for" error emitted by run.go:

go run run.go |& \
  sed -E -n 's/^(.*):(.*): no match for `([^ ]* (.*))` in:$/\1!\2!\3!\4/p' | \
  while IFS='!' read -r fn line before after; do
    before=$(echo "$before" | sed 's/[.[\*^$()+?{|]/\\&/g')
    after=$(echo "$after" | sed -E 's/(\&|\\)/\\&/g')
    fn=$(find . -name "${fn}" | head -1)
    sed -i -E -e "${line}s/\"${before}\"/\"${after}\"/" "${fn}"
  done

Passes toolstash-check.

Change-Id: I6e02486b1409e4a8dbb2b9b816d22095835426b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/195040
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarCherry Zhang <cherryyz@google.com>
      606019cb
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