JSON decoding performs poorly for unmapped and ignored fields. We noticed better
performance when unmarshalling unused fields. The loss comes mostly from calls
to scanner.error as described at #17914.
benchmark old ns/op new ns/op delta
BenchmarkIssue10335-8 431 408 -5.34%
BenchmarkUnmapped-8 1744 1314 -24.66%
benchmark old allocs new allocs delta
BenchmarkIssue10335-8 4 3 -25.00%
BenchmarkUnmapped-8 18 4 -77.78%
benchmark old bytes new bytes delta
BenchmarkIssue10335-8 320 312 -2.50%
BenchmarkUnmapped-8 568 344 -39.44%
Fixes#17914, improves #10335
Change-Id: I7d4258a94eb287c0fe49e7334795209b90434cd0
Reviewed-on: https://go-review.googlesource.com/33276
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is a workaround for a FreeBSD kernel bug. It can be removed when
we are confident that all people are using the fixed kernel. See #15658.
Updates #15658.
Change-Id: I0ecdccb77ddd0c270bdeac4d3a5c8abaf0449075
Reviewed-on: https://go-review.googlesource.com/38325
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This CL changes the order that liveness analysis visits CFG blocks to
PC order, rather than RPO. This doesn't meaningfully change anything
except that the PCDATA_StackMapIndex values will be assigned in PC
order too.
However, this does have the benefit that the subsequent CL to port
liveness analysis to the SSA CFG (which has blocks in PC order) will
now pass toolstash-check.
Change-Id: I1de5a2eecb8027723a6e422d46186d0c63d48c8d
Reviewed-on: https://go-review.googlesource.com/38086
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
This CL deletes some unnecessary code in objz.go that existed to
support instruction scheduling. It's likely instruction scheduling
will never be done in this part of the backend so this code can
just be deleted.
This file can probably be cleaned up a bit more, but I think this
is a good start.
Passes: go build -toolexec 'toolstash -cmp' -a std.
Change-Id: I1645632ac551a90a4f4be418045c046b488e9469
Reviewed-on: https://go-review.googlesource.com/38394
Run-TryBot: Michael Munday <munday@ca.ibm.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Teach the backend to recognize that the address of a symbol
is equal with itself, and that the addresses of two different
symbols are different.
Some examples of where this rule hits in the standard library:
- inlined uses of (*time.Time).setLoc (e.g. time.UTC)
- inlined uses of bufio.NewReader (via type assertion)
Change-Id: I23dcb068c2ec333655c1292917bec13bbd908c24
Reviewed-on: https://go-review.googlesource.com/38338
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When optimizations are disabled, the compiler
cannot eliminate enough write barriers to satisfy
the runtime's nowritebarrier and nowritebarrierrec
annotations.
Enforce that requirement, and for convenience,
have cmd/go elide -N when compiling the runtime.
This came up in practice for me when running
toolstash -cmp. When toolstash -cmp detected
mismatches, it recompiled with -N, which caused
runtime compilation failures.
Change-Id: Ifcdef22c725baf2c59a09470f00124361508a8f3
Reviewed-on: https://go-review.googlesource.com/38380
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Minor cleanup, to make it clearer
that the two p's are unrelated.
Change-Id: Icb6386c626681f60e5e631b33aa3a0fc84f40e4a
Reviewed-on: https://go-review.googlesource.com/38381
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Instead we can use t.nod.Pos.
Change-Id: I643ee3226e402e38d4c77e8f328cbe83e55eac5c
Reviewed-on: https://go-review.googlesource.com/38309
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
CL 27254 changed a constant string to a byte array
in encoding/hex and got significant performance
improvements.
hex.Encode used the string twice in a single function.
The rewrite rules lower constant strings into components.
The pointer component requires an aux symbol.
The existing implementation created a new aux symbol every time.
As a result, constant string pointers were never CSE'd.
Tighten then moved the pointer calculation next to the uses, i.e.
into the loop.
The re-use of aux syms enabled by this CL
occurs 3691 times during make.bash.
This CL should not go in without CL 38338
or something like it.
Change-Id: Ibbf5b17283c0e31821d04c7e08d995c654de5663
Reviewed-on: https://go-review.googlesource.com/28219
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Since "columns of alignment" are terminated whenever indentation
changes from one line to the next, alignment with spaces will work
independent of the actually chosen tab width. Don't mention tab width
anymore.
Follow-up on https://golang.org/cl/38374/.
For #19618.
Change-Id: I58e47dfde57834f56a98d9119670757a12fb9c41
Reviewed-on: https://go-review.googlesource.com/38379
Reviewed-by: Rob Pike <r@golang.org>
Report syntax error that was missed when moving to new parser.
Fixes#19610.
Change-Id: Ie5625f907a84089dc56fcccfd4f24df546042783
Reviewed-on: https://go-review.googlesource.com/38375
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
As noted in https://github.com/golang/go/issues/19161#issuecomment-287554171,
CL 37771 (adding use of the new httptest.Server.Client to all net/http
tests) accidentally reverted DisableKeepAlives for this test. For
many tests, DisableKeepAlives was just present to prevent goroutines
from staying active after the test exited. In this case it might
actually be important. (We'll see)
Updates #19161
Change-Id: I11f889f86c932b51b11846560b68dbe5993cdfc3
Reviewed-on: https://go-review.googlesource.com/38373
Reviewed-by: Michael Munday <munday@ca.ibm.com>
Mallocs and panics in the scavenge path are particularly nasty because
they're likely to silently self-deadlock on the mheap.lock. Avoid
sinking lots of time into debugging these issues in the future by
turning these into immediate throws.
Change-Id: Ib36fdda33bc90b21c32432b03561630c1f3c69bc
Reviewed-on: https://go-review.googlesource.com/38293
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
The lfstack API is still a C-style API: lfstacks all have unhelpful
type uint64 and the APIs are package-level functions. Make the code
more readable and Go-style by creating an lfstack type with methods
for push, pop, and empty.
Change-Id: I64685fa3be0e82ae2d1a782a452a50974440a827
Reviewed-on: https://go-review.googlesource.com/38290
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
This makes the overall naming and use of the functions
to create a Type more consistent.
Passes toolstash -cmp.
Change-Id: Ie0d40b42cc32b5ecf5f20502675a225038ea40e4
Reviewed-on: https://go-review.googlesource.com/38354
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
I noted in CL 38327 that the SSA test API felt a bit
clunky after the ssa.Func/ssa.Cache/ssa.Config refactoring,
and promised to clean it up once the dust settled.
The dust has settled.
Along the way, this CL fixes a potential latent bug,
in which the amd64 test context was used for all dummy Syslook calls.
The lone SSA test using the s390x context did not depend on the
Syslook context being correct, so the bug did not arise in practice.
Change-Id: If964251d1807976073ad7f47da0b1f1f77c58413
Reviewed-on: https://go-review.googlesource.com/38346
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Mapping all empty interfaces onto the same Type
allows better reuse of the ptrTo and sliceOf
Type caches for *interface{} and []interface{}.
This has little compiler performance impact now,
but it will be helpful in the future,
when we will eagerly populate some of those caches.
Passes toolstash-check.
Change-Id: I17daee599a129b0b2f5f3025c1be43d569d6782c
Reviewed-on: https://go-review.googlesource.com/38344
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This reduces the number of calls back into the
gc Type routines, which will help performance
in a concurrent backend.
It also reduces the number of callsites
that must be considered in making the transition.
Passes toolstash-check -all. No compiler performance changes.
Updates #15756
Change-Id: Ic7a8f1daac7e01a21658ae61ac118b2a70804117
Reviewed-on: https://go-review.googlesource.com/38340
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Prior to this CL, the ssa.Frontend field was responsible
for providing types to the backend during compilation.
However, the types needed by the backend are few and static.
It makes more sense to use a struct for them
and to hang that struct off the ssa.Config,
which is the correct home for readonly data.
Now that Types is a struct, we can clean up the names a bit as well.
This has the added benefit of allowing early construction
of all types needed by the backend.
This will be useful for concurrent backend compilation.
Passes toolstash-check -all. No compiler performance change.
Updates #15756
Change-Id: I021658c8cf2836d6a22bbc20cc828ac38c7da08a
Reviewed-on: https://go-review.googlesource.com/38336
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Currently, this second line is treated a pre-formatted text as it's
indented relatively to the BUG() line.
The current state can be seen at:
https://golang.org/cmd/gofmt/#pkg-note-BUG
Unindenting makes the rest of the sentence part of the same paragraph.
Change-Id: I6dee55c9c321b1a03b41c7124c6a1ea15772c878
Reviewed-on: https://go-review.googlesource.com/38353
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
While we're here, also eliminate a few more Curfn uses.
Passes toolstash -cmp. No compiler performance impact.
Updates #15756
Change-Id: Ib8db9e23467bbaf16cc44bf62d604910f733d6b8
Reviewed-on: https://go-review.googlesource.com/38331
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This is a first step towards eliminating the
Curfn global in the backend.
There's more to do.
Passes toolstash -cmp. No compiler performance impact.
Updates #15756
Change-Id: Ib09f550a001e279a5aeeed0f85698290f890939c
Reviewed-on: https://go-review.googlesource.com/38232
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Suggested by mdempsky in CL 38232.
This allows us to use the Frontend field
to associate frontend state and information
with a function.
See the following CL in the series for examples.
This is a giant CL, but it is almost entirely routine refactoring.
The ssa test API is starting to feel a bit unwieldy.
I will clean it up separately, once the dust has settled.
Passes toolstash -cmp.
Updates #15756
Change-Id: I71c573bd96ff7251935fce1391b06b1f133c3caf
Reviewed-on: https://go-review.googlesource.com/38327
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Prior to this CL, config was an explicit argument
to the SSA rewrite rules, and rules that needed
a Frontend got at it via config.
An upcoming CL moves Frontend from Config to Func,
so rules can no longer reach Frontend via Config.
Passing a Frontend as an argument to the rewrite rules
causes a 2-3% regression in compile times.
This CL takes a different approach:
It treats the variable names "config" and "fe"
as special and calculates them as needed.
The "as needed part" is also important to performance:
If they are calculated eagerly, the nilchecks themselves
cause a regression.
This introduces a little bit of magic into the rewrite
generator. However, from the perspective of the rules,
the config variable was already more or less magic.
And it makes the upcoming changes much clearer.
Passes toolstash -cmp.
Change-Id: I173f2bcc124cba43d53138bfa3775e21316a9107
Reviewed-on: https://go-review.googlesource.com/38326
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This CL changes the GOARCH.Init functions to take gc.Thearch as a
parameter, which gc.Main supplies.
Additionally, the x86 backend is refactored to decide within Init
whether to use the 387 or SSE2 instruction generators, rather than for
each individual SSA Value/Block.
Passes toolstash-check -all.
Change-Id: Ie6305a6cd6f6ab4e89ecbb3cbbaf5ffd57057a24
Reviewed-on: https://go-review.googlesource.com/38301
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
This reduces memory use yet still provides the significant
performance gain seen when using a fast path for small integers.
Improvement of this CL comparing to code without fast path:
name old time/op new time/op delta
FormatIntSmall-8 35.6ns ± 1% 4.5ns ± 1% -87.30% (p=0.008 n=5+5)
AppendIntSmall-8 17.4ns ± 1% 9.4ns ± 3% -45.70% (p=0.008 n=5+5)
For comparison, here's the improvement before this CL to code without
fast path (1% better for FormatIntSmall):
name old time/op new time/op delta
FormatIntSmall-8 35.6ns ± 1% 4.0ns ± 3% -88.64% (p=0.008 n=5+5)
AppendIntSmall-8 17.4ns ± 1% 8.2ns ± 1% -52.80% (p=0.008 n=5+5)
Thus, the code in this CL performs slower for small integers using fast
path then the prior version, but this is relative to an already very fast
version:
name old time/op new time/op delta
FormatIntSmall-8 4.05ns ± 3% 4.52ns ± 1% +11.81% (p=0.008 n=5+5)
AppendIntSmall-8 8.21ns ± 1% 9.45ns ± 3% +15.05% (p=0.008 n=5+5)
Measured on 2.3 GHz Intel Core i7 running macOS Sierra 10.12.3.
Overall, it's still ~88% faster than without fast path for small integers,
so probably worth it as it removes 100 global string slices in favor of
a single string.
Credits: This is based on the original (but cleaned up) version of the
code by Aliaksandr Valialkin (https://go-review.googlesource.com/c/37963/).
Change-Id: Icda78679c8c14666d46257894e9fa3d7f35e58b8
Reviewed-on: https://go-review.googlesource.com/38319
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Its godoc says that path must not be empty or dot, while the existing
implementation happily accepts both.
Change-Id: I64766271c35152dc7adb21ff60eb05c52237e6b6
Reviewed-on: https://go-review.googlesource.com/38262
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
I don't know that it exists for any other architectures.
Update #18616
Change-Id: Idfe5dee251764d32787915889ec0be4bebc5be24
Reviewed-on: https://go-review.googlesource.com/38323
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
`go test -i -race` adds the "sync/atomic" package to every package dependency tree
that makes buildIDs different from packages installed with `go install -race`
and causes cache rebuilding.
Fixes#19133Fixes#19151
Change-Id: I0536c6fa41b0d20fe361b5d35b3c0937b146d07d
Reviewed-on: https://go-review.googlesource.com/37598
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
