Remove almost all the remaining Nod(OXXX, ... ) uses. The performance
change is due entirely to the changes to func temp(*Type). The other
cleanups have no effect, as expected.
I'll address the remaining Nod(OXXX, ...) uses in a followup CL as they
are very sensitive to change.
Brad Fitzpatrick [Sun, 20 Mar 2016 20:20:01 +0000 (07:20 +1100)]
cmd/compile: reduce some SSA garbage
It's pretty hard to get reliable CPU numbers, even with 50 runs on an
otherwise-idle physical Linux machine, but the garbage reduction
numbers are nice. To get useful time/op numbers, I modified
compilebench to report user CPU time instead of wall time:
Matthew Dempsky [Wed, 23 Mar 2016 18:07:20 +0000 (11:07 -0700)]
cmd/compile: small Mpint method simplifications
Get rid of (*Mpint).Add's "quiet" parameter: it's always set to 0.
Inline (*Mpint).shift into (*Mpint).Lsh and (*Mpint).Rsh. There's no
need for a common shift method that can handle both left or right
shifts based on sign when the higher level abstractions only ever do
one or the other.
Change-Id: Icd3b082413f9193961b6835279e0bd4b6a6a6621
Reviewed-on: https://go-review.googlesource.com/21050
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
Alexandru Moșoi [Wed, 23 Mar 2016 10:11:34 +0000 (11:11 +0100)]
cmd/compile: don't simplify nilchecks in loops
khr: Lifting the nil check out of the loop altogether is an admirable
goal, and this rewrite is one step on the way. But without lifting it
out of the loop, the rewrite is just hurting us.
Fixes #14917
Change-Id: Idb917f37d89f50f8e046d5ebd7c092b1e0eb0633
Reviewed-on: https://go-review.googlesource.com/21040 Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Lynn Boger [Mon, 7 Mar 2016 17:59:16 +0000 (11:59 -0600)]
bytes: Equal perf improvements on ppc64le/ppc64
The existing implementation for Equal and similar
functions in the bytes package operate on one byte at
at time. This performs poorly on ppc64/ppc64le especially
when the byte buffers are large. This change improves
those functions by loading and comparing double words where
possible. The common code has been moved to a function
that can be shared by the other functions in this
file which perform the same type of comparison.
Further optimizations are done for the case where
>= 32 bytes are being compared. The new function
memeqbody is used by memeq_varlen, Equal, and eqstring.
When running the bytes test with -test.bench=Equal
Klaus Post [Mon, 21 Mar 2016 09:21:55 +0000 (10:21 +0100)]
compress/flate: rework matching algorithm
This changes how matching is done in deflate algorithm.
The major change is that we do not look for matches that are only
3 bytes in length, matches must be 4 bytes at least.
Contrary to what you would expect this actually improves the
compresion ratio, since 3 literal bytes will often be shorter
than a match after huffman encoding.
This varies a bit by source, but is most often the case when the
source is "easy" to compress.
Second of all, a "stronger" hash is used. The hash is similar to
the hashing function used by Snappy.
Overall, the speed impact is biggest on higher compression levels.
I intend to replace the "speed" compression level, which can be
seen in CL 21021.
The built-in benchmark using "digits" is slower at level 1.
I see this as an exception, since "digits" is a special type
of data, where you have low entropy (numbers 0->9), but no
significant matches. Again, CL 20021 fixes that case.
NewWriterDict is also made considerably faster, by not running data
through the entire encoder. This is not reflected by the benchmark.
Overall, the speed impact is biggest on higher compression levels.
I intend to replace the "speed" compression level.
Martin Möhrmann [Sun, 20 Mar 2016 14:24:50 +0000 (15:24 +0100)]
fmt: cleanup and optimize doPrintf for simple formats
Make a fast path for format strings that do not use
precision or width specifications or argument indices.
Only check and enforce the restriction to not pad left with zeros
in code paths that change either f.minus or f.zero.
Consolidate the if chains at the end of the main doPrintf loop
into a switch statement. Move error printing into extra
functions to reduce size of this switch statement.
Tamir Duberstein [Fri, 12 Feb 2016 05:37:52 +0000 (00:37 -0500)]
database/sql/driver: remove string exclusion
The exclusion of string from IsScanValue prevents driver authors from
writing their drivers in such a way that would allow users to
distinguish between strings and byte arrays returned from a database.
Such drivers are possible today, but require their authors to deviate
from the guidance provided by the standard library.
This exclusion has been in place since the birth of this package in
https://github.com/golang/go/commit/357f2cb1a385f4d1418e48856f9abe0cce,
but the fakedb implementation shipped in the same commit violates the
exclusion!
Strictly speaking this is a breaking change, but it increases the set
of permissible Scan types, and should not cause breakage in practice.
No test changes are necessary because fakedb already exercises this.
Ian Lance Taylor [Wed, 23 Mar 2016 01:17:43 +0000 (18:17 -0700)]
misc/cgo/testcarchive: rewrite test from bash to Go
This is to support https://golang.org/cl/18057, which is going to add
Windows support to this directory. Better to write the test in Go then
to have both test.bash and test.bat.
Update #13494.
Change-Id: I4af7004416309e885049ee60b9470926282f210d
Reviewed-on: https://go-review.googlesource.com/20892
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Michael Munday [Tue, 22 Mar 2016 19:08:09 +0000 (15:08 -0400)]
syscall: correct spelling/typos in comment
Change-Id: Ib44c6b1ce07aa8fb67033cf21e177a90fd4005dc
Reviewed-on: https://go-review.googlesource.com/21002 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Escape analysis has a hard time with tree-like
structures (see #13493 and #14858).
This is unlikely to change.
As a result, when invoking a function that accepts
a **Node parameter, we usually allocate a *Node
on the heap. This happens a whole lot.
This CL changes functions from taking a **Node
to acting more like append: It both modifies
the input and returns a replacement for it.
Because of the cascading nature of escape analysis,
in order to get the benefits, I had to modify
almost all such functions. The remaining functions
are in racewalk and the backend. I would be happy
to update them as well in a separate CL.
This CL was created by manually updating the
function signatures and the directly impacted
bits of code. The callsites were then automatically
updated using a bespoke script:
https://gist.github.com/josharian/046b1be7aceae244de39
For ease of reviewing and future understanding,
this CL is also broken down into four CLs,
mailed separately, which show the manual
and the automated changes separately.
They are CLs 20990, 20991, 20992, and 20993.
name old text-bytes new text-bytes delta
HelloSize 578k ± 0% 578k ± 0% ~ (all samples are equal)
CmdGoSize 6.46M ± 0% 6.46M ± 0% ~ (all samples are equal)
name old data-bytes new data-bytes delta
HelloSize 128k ± 0% 128k ± 0% ~ (all samples are equal)
CmdGoSize 281k ± 0% 281k ± 0% ~ (all samples are equal)
name old exe-bytes new exe-bytes delta
HelloSize 921k ± 0% 921k ± 0% ~ (all samples are equal)
CmdGoSize 9.86M ± 0% 9.86M ± 0% ~ (all samples are equal)
Change-Id: I277d95bd56d51c166ef7f560647aeaa092f3f475
Reviewed-on: https://go-review.googlesource.com/20959 Reviewed-by: Dave Cheney <dave@cheney.net> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Ian Lance Taylor [Wed, 16 Mar 2016 21:15:54 +0000 (14:15 -0700)]
debug/dwarf: add Reader.SeekPC and Data.Ranges
These new methods help find the compilation unit to pass to the
LineReader method in order to find the line information for a PC.
The Ranges method also helps identify the specific function for a PC,
needed to determine the function name.
This uses the .debug.ranges section if necessary, and changes the object
file format packages to pass in the section contents if available.
Change-Id: I5ebc3d27faaf1a126ffb17a1e6027efdf64af836
Reviewed-on: https://go-review.googlesource.com/20769 Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Keith Randall [Mon, 21 Mar 2016 23:18:45 +0000 (16:18 -0700)]
cmd/compile: allow naming of subexpressions
Allow names to be used for subexpressions of match rules.
For example:
(OpA x:(OpB y)) -> ..use x here to refer to the OpB value..
This gets rid of the .Args[0].Args[0]... way of naming we
used to use.
While we're here, give all subexpression matches names instead
of recomputing them with .Args[i] sequences each time they
are referenced. Makes the generated rule code a bit smaller.
Robert Griesemer [Fri, 18 Mar 2016 18:16:35 +0000 (11:16 -0700)]
math/big: fix rounding to smallest denormal for Float.Float32/64
Converting a big.Float value x to a float32/64 value did not correctly
round x up to the smallest denormal float32/64 if x was smaller than the
smallest denormal float32/64, but larger than 0.5 of a smallest denormal
float32/64.
Handle this case explicitly and simplify some code in the turn.
For #14651.
Change-Id: I025e24bf8f0e671581a7de0abf7c1cd7e6403a6c
Reviewed-on: https://go-review.googlesource.com/20816
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Alan Donovan <adonovan@google.com>
Keith Randall [Mon, 7 Mar 2016 00:58:30 +0000 (16:58 -0800)]
runtime: use MOVSB instead of MOVSQ for unaligned moves
MOVSB is quite a bit faster for unaligned moves.
Possibly we should use MOVSB all of the time, but Intel folks
say it might be a bit faster to use MOVSQ on some processors
(but not any I have access to at the moment).
benchmark old ns/op new ns/op delta
BenchmarkMemmove4096-8 93.9 93.2 -0.75%
BenchmarkMemmoveUnalignedDst4096-8 256 151 -41.02%
BenchmarkMemmoveUnalignedSrc4096-8 175 90.5 -48.29%
Fixes #14630
Change-Id: I568e6d6590eb3615e6a699fb474020596be665ff
Reviewed-on: https://go-review.googlesource.com/20293 Reviewed-by: Ian Lance Taylor <iant@golang.org>
cmd/internal/obj: change linkgetline from C to Go func style
Passes toolstash -cmp.
Change-Id: I8725dee490778be9c1fd31990a6b27df9713c3c9
Reviewed-on: https://go-review.googlesource.com/20957 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Matthew Dempsky [Sun, 20 Mar 2016 20:55:42 +0000 (13:55 -0700)]
cmd/compile: change Mp{int,flt} functions into methods
Also give them more idiomatic Go names. Adding godocs is outside the
scope of this CL. (Besides, the method names almost all directly
parallel an underlying math/big.Int or math/big.Float method.)
CL prepared mechanically with sed (for rewriting mpint.go/mpfloat.go)
and gofmt (for rewriting call sites).
Passes toolstash -cmp.
Change-Id: Id76f4aee476ba740f48db33162463e7978c2083d
Reviewed-on: https://go-review.googlesource.com/20909
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org>
Michael Munday [Fri, 18 Mar 2016 21:14:23 +0000 (17:14 -0400)]
cmd/go: add s390x support
Minimum architecture of z196 required so that GCC can assemble
gcc_s390x.S in runtime/cgo.
Change-Id: I603ed2edd39f826fb8193740ece5bd11d18c3dc5
Reviewed-on: https://go-review.googlesource.com/20876 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Michael Munday [Mon, 21 Mar 2016 03:00:40 +0000 (23:00 -0400)]
cmd/dist: enable -shared and external linking tests on s390x
Change-Id: Iedd01ef3a9d2831cb55c53b7a1984e7e932f4249
Reviewed-on: https://go-review.googlesource.com/20932 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Michael Munday [Sun, 20 Mar 2016 23:25:58 +0000 (19:25 -0400)]
test/fixedbugs: add s390x case to issue11656
An instruction consisting of all 0s causes an illegal instruction
signal on s390x. Since 0s are the default in this test this CL just
makes it explicit.
can never be true: if dup != nil, then s.Name is ".dup" (and this is not new:
the same broken logic is present in 1.4, at least). Delete the whole block.
Dave Cheney [Mon, 21 Mar 2016 03:19:57 +0000 (14:19 +1100)]
cmd/internal/obj: move Nocache helper to arm back end
The obj.Nocache helper was only used by the arm back end, move it there.
Change-Id: I5c9faf995499991ead1f3d8c8ffc3b6af7346876
Reviewed-on: https://go-review.googlesource.com/20868 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Matthew Dempsky [Sun, 20 Mar 2016 21:54:13 +0000 (14:54 -0700)]
math/big: cleanup documentation for Format methods
'b' is a standard verb for floating point values. The runes like '+'
and '#' are called "flags" by package fmt's documentation. The flag
'-' controls left/right justification, not anything related to signs.
Richard Miller [Sun, 20 Mar 2016 19:17:36 +0000 (19:17 +0000)]
net/http: adaptive wait time in PersistConnLeak tests
In tests TransportPersistConnLeak and TransportPersistConnLeakShortBody,
there's a fixed wait time (100ms and 400ms respectively) to allow
goroutines to exit after CloseIdleConnections is called. This
is sometimes too short on a slow host running many simultaneous
tests.
This CL replaces the fixed sleep in each test with a sequence of
shorter sleeps, testing the number of remaining goroutines until
it reaches the threshold or an overall time limit of 500ms expires.
This prevents some failures in the plan9_arm builder, while reducing
the test time on faster machines.
Ian Lance Taylor [Sun, 20 Mar 2016 17:25:46 +0000 (10:25 -0700)]
cmd/compile: fix varexpr handling of ODOT
For a long time varexpr has handled ODOT incorrectly: it has always
returned false. Before https://golang.org/cl/20890 this has been
because an ODOT had a Right field with an ONAME with no Class, for which
varexpr returns false. CL 20890 preserved the behavior of varexpr for
ODOT, so that the change would pass toolstash -cmp.
This CL fixes varexpr so that ODOT can return true in some cases. This
breaks toolstash -cmp. While the changed compiler allocates temporary
variables in a different order, I have not been able to find any
examples where the generated code is different, other than using
different stack offsets and, in some cases, registers. It seems that
other parts of the compiler will force the ODOT into a temporary anyhow.
Still, this change is clearly correct, and is a minor compiler cleanup.
Change-Id: I71506877aa3c13966bb03c281aa16271ee7fe80a
Reviewed-on: https://go-review.googlesource.com/20907
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Ian Lance Taylor [Sat, 19 Mar 2016 01:12:14 +0000 (18:12 -0700)]
cmd/compile: don't penalize ODOT and friends when inlining
Historically ODOT and friends have been considered to cost an extra
budget point when deciding whether they should be inlined, because they
had an ONAME node that represented the name to the right of the dot.
This doesn't really make sense, as in general that symbol does not add
any extra instructions; it just affects the offset of the load or store
instruction. And the ONAME node is gone now. So, remove the extra
cost.
This does not pass toolstash -cmp, as it changes inlining decisions.
For example, mspan.init in runtime/mheap.go is now considered to be an
inlining candidate.
Change-Id: I5ad27f08c66fd5daa4c8472dd0795df989183f5e
Reviewed-on: https://go-review.googlesource.com/20891 Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Matthew Dempsky [Sun, 20 Mar 2016 00:51:17 +0000 (17:51 -0700)]
cmd/compile: ignore receiver name when checking duplicate methods
In golang.org/cl/20602, I changed the semantics of Eqtype to stop
checking the receiver parameters for type equality, and pushed this
responsibility to addmethod (the only Eqtype caller that cared).
However, I accidentally made the check stricter by making it start
requiring that receiver names were identical.
In general, this is a non-problem because the receiver names in export
data will always match the original source. But running
GO_GCFLAGS=-newexport ./all.bash at one point tries to load both old
and new format export data for package sync, which reveals the
problem. (See golang.org/issue/14877 for details.)
Easy fix: just check the receiver type for type equality in addmethod,
instead of the entire receiver parameter list.
Martin Möhrmann [Sat, 19 Mar 2016 12:18:43 +0000 (13:18 +0100)]
fmt: remove depth argument from handleMethods and printArg
handleMethods can format Error() and String() directly as its known
these return strings that can be directly printed using fmtString.
Remove the obsolete depth argument from handleMethods.
Remove the depth argument from printArg since it is only ever
called with depth set to 0. Recursion for formatting complex
arguments is handled only by printValue which keeps track of depth.
Change-Id: I4c4be588751de12ed999e7561a51bc168eb9eb2d
Reviewed-on: https://go-review.googlesource.com/20911
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Ian Lance Taylor [Fri, 18 Mar 2016 23:52:30 +0000 (16:52 -0700)]
cmd/compile: change ODOT and friends to use Sym, not Right
The Node type ODOT and its variants all represent a selector, with a
simple name to the right of the dot. Before this change this was
represented by using an ONAME Node in the Right field. This ONAME node
served no useful purpose. This CL changes these Node types to store the
symbol in the Sym field instead, thus not requiring allocating a Node
for each selector.
When compiling x/tools/go/types this CL eliminates nearly 5000 calls to
newname and reduces the total number of Nodes allocated by about 6.6%.
It seems to cut compilation time by 1 to 2 percent.
Getting this right was somewhat subtle, and I added two dubious changes
to produce the exact same output as before. One is to ishairy in
inl.go: the ONAME node increased the cost of ODOT and friends by 1, and
I retained that, although really ODOT is not more expensive than any
other node. The other is to varexpr in walk.go: because the ONAME in
the Right field of an ODOT has no class, varexpr would always return
false for an ODOT, although in fact for some ODOT's it seemingly ought
to return true; I added an && false for now. I will send separate CLs,
that will break toolstash -cmp, to clean these up.
Todd Neal [Wed, 16 Mar 2016 23:44:17 +0000 (18:44 -0500)]
cmd/compile: allow inlining of functions that declare a const
Consider functions with an ODCLCONST for inlining and modify exprfmt to
ignore those nodes when exporting. Don't add symbols to the export list
if there is no definition. This occurs when OLITERAL symbols are looked
up via Pkglookup for non-exported symbols.
Martin Möhrmann [Fri, 18 Mar 2016 15:56:47 +0000 (16:56 +0100)]
fmt: simplify handling of reporting flags to formatters
Remove rewriting of flags before calling formatters.
Change Flag method to directly take plusV and sharpV flags
into account when reporting if plus or sharp flag is set.
Change-Id: Ic3423881ad89e5a5f9fff5ab59e842062394ef6d
Reviewed-on: https://go-review.googlesource.com/20859
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>