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Commit Graph

3754 Commits

Author SHA1 Message Date
Keith Randall
009d714098 cmd/compile, runtime: store pointers to go:notinheap types indirectly
pointers to go:notinheap types should be treated as scalars. That
means they shouldn't be stored directly in interfaces, or directly
in reflect.Value.ptr.

Also be sure to use uintpr to compare such pointers in reflect.DeepEqual.

Fixes #42076

Change-Id: I53735f6d434e9c3108d4940bd1bae14c61ef2a74
Reviewed-on: https://go-review.googlesource.com/c/go/+/264480
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-27 21:29:13 +00:00
Keith Randall
933721b8c7 cmd/compile: fix storeType to handle pointers to go:notinheap types
storeType splits compound stores up into a scalar parts and a pointer parts.
The scalar part happens unconditionally, and the pointer part happens
under the guard of a write barrier check.

Types which are declared as pointers, but are represented as scalars because
they might have "bad" values, were not handled correctly here. They ended
up not getting stored in either set.

Fixes #42032

Change-Id: I46f6600075c0c370e640b807066247237f93c7ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/264300
Trust: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-27 21:28:53 +00:00
Paul E. Murphy
c3c6fbf314 cmd/compile: combine more 32 bit shift and mask operations on ppc64
Combine (AND m (SRWconst x)) or (SRWconst (AND m x)) when mask m is
and the shift value produce constant which can be encoded into an
RLWINM instruction.

Combine (CLRLSLDI (SRWconst x)) if the combining of the underling rotate
masks produces a constant which can be encoded into RLWINM.

Likewise for (SLDconst (SRWconst x)) and (CLRLSDI (RLWINM x)).

Combine rotate word + and operations which can be encoded as a single
RLWINM/RLWNM instruction.

The most notable performance improvements arise from the crypto
benchmarks below (GOARCH=power8 on a ppc64le/linux):

pkg:golang.org/x/crypto/blowfish goos:linux goarch:ppc64le
ExpandKeyWithSalt                               52.2µs ± 0%    47.5µs ± 0%  -8.88%
ExpandKey                                       44.4µs ± 0%    40.3µs ± 0%  -9.15%

pkg:golang.org/x/crypto/ssh/internal/bcrypt_pbkdf goos:linux goarch:ppc64le
Key                                             57.6ms ± 0%    52.3ms ± 0%  -9.13%

pkg:golang.org/x/crypto/bcrypt goos:linux goarch:ppc64le
Equal                                           90.9ms ± 0%    82.6ms ± 0%  -9.13%
DefaultCost                                     91.0ms ± 0%    82.7ms ± 0%  -9.12%

Change-Id: I59a0ca29face38f4ab46e37124c32906f216c4ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/260798
Run-TryBot: Carlos Eduardo Seo <carlos.seo@linaro.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.com>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
2020-10-27 18:33:20 +00:00
Cuong Manh Le
a19cf510af cmd/compile: defer lowering OANDNOT until SSA
Currently, "x &^ y" gets rewriten into "x & ^y" during walk. It adds
unnecessary complexity to other parts, which must aware about this.

Instead, we can just implement "&^" in the conversion to SSA, so "&^"
can be handled like other binary operators.

However, this CL does not pass toolstash-check. It seems that implements
"&^" in the conversion to SSA causes registers allocation change.

With the parent:

obj: 00212 (.../src/runtime/complex.go:47)    MOVQ    X0, AX
obj: 00213 (.../src/runtime/complex.go:47)    BTRQ    $63, AX
obj: 00214 (.../src/runtime/complex.go:47)    MOVQ    "".n(SP), CX
obj: 00215 (.../src/runtime/complex.go:47)    MOVQ    $-9223372036854775808, DX
obj: 00216 (.../src/runtime/complex.go:47)    ANDQ    DX, CX
obj: 00217 (.../src/runtime/complex.go:47)    ORQ AX, CX

With this CL:

obj: 00212 (.../src/runtime/complex.go:47)    MOVQ    X0, AX
obj: 00213 (.../src/runtime/complex.go:47)    BTRQ    $63, AX
obj: 00214 (.../src/runtime/complex.go:47)    MOVQ    $-9223372036854775808, CX
obj: 00215 (.../src/runtime/complex.go:47)    MOVQ    "".n(SP), DX
obj: 00216 (.../src/runtime/complex.go:47)    ANDQ    CX, DX
obj: 00217 (.../src/runtime/complex.go:47)    ORQ AX, DX

Change-Id: I80acf8496a91be4804fb7ef3df04c19baae2754c
Reviewed-on: https://go-review.googlesource.com/c/go/+/264660
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-27 03:11:45 +00:00
Cuong Manh Le
fb7134e4e3 test: add index bounds check elided with "&^"
For follow up CL, which will defer lowering OANDNOT until SSA.

Change-Id: I5a988d0b8f0ae664580f08b123811b2a31ef55c6
Reviewed-on: https://go-review.googlesource.com/c/go/+/265040
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-27 02:33:40 +00:00
Cherry Zhang
c9c64886ef cmd/internal/obj: reject too large symbols
We never supported symbol larger than 2GB (issue #9862), so the
object file uses 32-bit for symbol sizes. Check and reject too
large symbol before truncating its size.

Fixes #42054.

Change-Id: I0d1d585ebdba9556f2fd3a97043bd4296d5cc9e4
Reviewed-on: https://go-review.googlesource.com/c/go/+/263641
Trust: Cherry Zhang <cherryyz@google.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
2020-10-20 18:51:03 +00:00
Cuong Manh Le
bccdd31252 cmd/compile: use type position for error message in align.go
This helps the compiler reports the right place where the type declared,
instead of relying on global lineno, which maybe set to wrong value at
the time the error is reported.

Fixes #42058

Change-Id: I06d34aa9b0236d122f4a0d72e66675ded022baac
Reviewed-on: https://go-review.googlesource.com/c/go/+/263597
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2020-10-20 02:05:01 +00:00
Dan Scales
8fe372c7b3 cmd/compile: allowing inlining of functions with OCALLPART
OCALLPART is exported in its original form, which is as an OXDOT.

The body of the method value wrapper created in makepartialcall() was
not being typechecked, and that was causing a problem during escape
analysis, so I added code to typecheck the body.

The go executable got slightly bigger with this change (13598111 ->
13598905), because of extra exported methods with OCALLPART (I
believe), while the text size got slightly smaller (9686964 ->
9686643).

This is mainly part of the work to make sure all function bodies can
be exported (for purposes of generics), but might as well fix the
OCALLPART inlining bug as well.

Fixes #18493

Change-Id: If7aa055ff78ed7a6330c6a1e22f836ec567d04fd
Reviewed-on: https://go-review.googlesource.com/c/go/+/263620
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-20 00:07:42 +00:00
Matthew Dempsky
c216ae80c9 cmd/compile: fix ICE in reporting of invalid recursive types
asNode(t.Nod).Name.Param will be nil for builtin types (i.e., the
universal predeclared types and unsafe.Pointer). These types can't be
part of a cycle anyway, so we can just skip them.

Fixes #42075.

Change-Id: Ic7a44de65c6bfd16936545dee25e36de8850acf3
Reviewed-on: https://go-review.googlesource.com/c/go/+/263717
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2020-10-19 21:30:43 +00:00
Matthew Dempsky
76a615b20a cmd/compile: fix defer/go calls to variadic unsafe-uintptr functions
Before generating wrapper function, turn any f(a, b, []T{c, d, e}...)
calls back into f(a, b, c, d, e). This allows the existing code for
recognizing and specially handling unsafe.Pointer->uintptr conversions
to correctly handle variadic arguments too.

Fixes #41460.

Change-Id: I0a1255abdd1bd5dafd3e89547aedd4aec878394c
Reviewed-on: https://go-review.googlesource.com/c/go/+/263297
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-10-17 21:30:53 +00:00
Matthew Dempsky
1bcf6beec5 cmd/compile: use staticValue for inlining logic
This CL replaces the ad hoc and duplicated logic for detecting
inlinable calls with a single "inlCallee" function, which uses the
"staticValue" helper function introduced in an earlier commit.

Updates #41474.

Change-Id: I103d4091b10366fce1344ef2501222b7df68f21d
Reviewed-on: https://go-review.googlesource.com/c/go/+/256460
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-10-15 18:35:44 +00:00
Matthew Dempsky
497ea0610e cmd/compile: allow inlining of "for" loops
We already allow inlining "if" and "goto" statements, so we might as
well allow "for" loops too. The majority of frontend support is
already there too.

The critical missing feature at the moment is that inlining doesn't
properly reassociate OLABEL nodes with their control statement (e.g.,
OFOR) after inlining. This eventually causes SSA construction to fail.

As a workaround, this CL only enables inlining for unlabeled "for"
loops. It's left to a (yet unplanned) future CL to add support for
labeled "for" loops.

The increased opportunity for inlining leads to a small growth in
binary size. For example:

$ size go.old go.new
   text	   data	    bss	    dec	    hex	filename
9740163	 320064	 230656	10290883	 9d06c3	go.old
9793399	 320064	 230656	10344119	 9dd6b7	go.new

Updates #14768.
Fixes #41474.

Change-Id: I827db0b2b9d9fa2934db05caf6baa463f0cd032a
Reviewed-on: https://go-review.googlesource.com/c/go/+/256459
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-10-15 18:26:33 +00:00
Matthew Dempsky
c0417df156 cmd/compile: improve escape analysis of known calls
Escape analysis is currently very naive about identifying calls to
known functions: it only recognizes direct calls to a declared
function, or direct calls to a closure.

This CL adds a new "staticValue" helper function that can trace back
through local variables that were initialized and never reassigned
based on a similar optimization already used by inlining. (And to be
used by inlining in a followup CL.)

Updates #41474.

Change-Id: I8204fd3b1e150ab77a27f583985cf099a8572b2e
Reviewed-on: https://go-review.googlesource.com/c/go/+/256458
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
2020-10-15 18:26:06 +00:00
Ian Lance Taylor
e43ef8dda2 test: add test that fails with gofrontend
The gofrontend code doesn't correctly handle inlining a function that
refers to a constant with methods.

For #35739

Change-Id: I6bd0b5cd4272dbe9969634b4821e668acacfdcf9
Reviewed-on: https://go-review.googlesource.com/c/go/+/261662
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-10-13 22:50:26 +00:00
Russ Cox
2c6df2e35d cmd/compile: reject misplaced go:build comments
We are converting from using error-prone ad-hoc syntax // +build lines
to less error-prone, standard boolean syntax //go:build lines.
The timeline is:

Go 1.16: prepare for transition
 - Builds still use // +build for file selection.
 - Source files may not contain //go:build without // +build.
 - Builds fail when a source file contains //go:build lines without // +build lines. <<<

Go 1.17: start transition
 - Builds prefer //go:build for file selection, falling back to // +build
   for files containing only // +build.
 - Source files may contain //go:build without // +build (but they won't build with Go 1.16).
 - Gofmt moves //go:build and // +build lines to proper file locations.
 - Gofmt introduces //go:build lines into files with only // +build lines.
 - Go vet rejects files with mismatched //go:build and // +build lines.

Go 1.18: complete transition
 - Go fix removes // +build lines, leaving behind equivalent // +build lines.

This CL provides part of the <<< marked line above in the Go 1.16 step:
rejecting files containing //go:build but not // +build.
The standard go command checks only consider the top of the file.
This compiler check, along with a separate go vet check for ignored files,
handles the remainder of the file.

For #41184.

Change-Id: I014006eebfc84ab5943de18bc90449e534f150a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/240601
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-13 01:16:45 +00:00
Keith Randall
a4b95cd092 cmd/compile: fix incorrect comparison folding
We lost a sign extension that was necessary. The nonnegative comparison
didn't have the correct extension on it. If the larger constant is
positive, but its shorter sign extension is negative, the rule breaks.

Fixes #41872

Change-Id: I6592ef103f840fbb786bf8cb94fd8804c760c976
Reviewed-on: https://go-review.googlesource.com/c/go/+/260701
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
2020-10-08 20:35:54 +00:00
Keith Randall
04b8a9fea5 all: implement GO386=softfloat
Backstop support for non-sse2 chips now that 387 is gone.

RELNOTE=yes

Change-Id: Ib10e69c4a3654c15a03568f93393437e1939e013
Reviewed-on: https://go-review.googlesource.com/c/go/+/260017
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-06 22:49:38 +00:00
Cherry Zhang
2e4ceaf963 cmd/dist: enable more tests on macOS/ARM64
Unlike iOS, macOS ARM64 is more of a fully featured OS. Enable
more tests.

Updates #38485.

Change-Id: I2e2240c848d21996db2b950a4a6856987f7a652c
Reviewed-on: https://go-review.googlesource.com/c/go/+/256919
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-10-06 21:55:49 +00:00
David Chase
f8d80977b7 cmd/compile: correct leaf type when "selecting" singleton register-sized struct
Two part fix:
1) bring the type "correction" forward from a later CL in the expand calls series
2) when a leaf-selwect is rewritten in place, update the type (it might have been
   changed by the type correction in 1).

Fixes #41736.

Change-Id: Id097efd10481bf0ad92aaead81a7207221c144b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/259203
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-10-06 15:37:42 +00:00
David Chase
694025e74f cmd/compile: avoid applying ARM CMP->CMN rewrite in unsigned context
Fixes #41780.

Change-Id: I1dc7c19a9f057650905da3a96214c2ff4abb51be
Reviewed-on: https://go-review.googlesource.com/c/go/+/259450
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-10-06 01:14:39 +00:00
Alberto Donizetti
095e0f48a1 cmd/compile: change mustHeapAlloc to return a reason why
This change renames mustHeapAlloc to heapAllocReason, and changes it
to return the reason why the argument must escape, so we don't have to
re-deduce it in its callers just to print the escape reason. It also
embeds isSmallMakeSlice body in heapAllocReason, since the former was
only used by the latter, and deletes isSmallMakeSlice.

An outdated TODO to remove smallintconst, which the TODO claimed was
only used in one place, was also removed, since grepping shows we
currently call smallintconst in 11 different places.

Change-Id: I0bd11bf29b92c4126f5bb455877ff73217d5a155
Reviewed-on: https://go-review.googlesource.com/c/go/+/258678
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-10-03 13:02:20 +00:00
Keith Randall
fe2cfb74ba all: drop 387 support
My last 387 CL. So sad ... ... ... ... not!

Fixes #40255

Change-Id: I8d4ddb744b234b8adc735db2f7c3c7b6d8bbdfa4
Reviewed-on: https://go-review.googlesource.com/c/go/+/258957
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-10-02 00:00:51 +00:00
Lynn Boger
cc2a5cf4b8 cmd/compile,cmd/internal/obj/ppc64: fix some shift rules due to a regression
A recent change to improve shifts was generating some
invalid cases when the rule was based on an AND. The
extended mnemonics CLRLSLDI and CLRLSLWI only allow
certain values for the operands and in the mask case
those values were not being checked properly. This
adds a check to those rules to verify that the
'b' and 'n' values used when an AND was part of the rule
have correct values.

There was a bug in some diag messages in asm9. The
message expected 3 values but only provided 2. Those are
corrected here also.

The test/codegen/shift.go was updated to add a few more
cases to check for the case mentioned here.

Some of the comments that mention the order of operands
in these extended mnemonics were wrong and those have been
corrected.

Fixes #41683.

Change-Id: If5bb860acaa5051b9e0cd80784b2868b85898c31
Reviewed-on: https://go-review.googlesource.com/c/go/+/258138
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
Reviewed-by: Carlos Eduardo Seo <carlos.seo@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
2020-10-01 18:51:18 +00:00
Matthew Dempsky
0e85fd7561 cmd/compile: report type loop for invalid recursive types
Similar to how we report initialization loops in initorder.go and type
alias loops in typecheck.go, this CL updates align.go to warn about
invalid recursive types. The code is based on the loop code from
initorder.go, with minimal changes to adapt from detecting
variable/function initialization loops to detecting type declaration
loops.

Thanks to Cuong Manh Le for investigating this, helping come up with
test cases, and exploring solutions.

Fixes #41575
Updates #41669.

Change-Id: Idb2cb8c5e1d645e62900e178fcb50af33e1700a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/258177
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
2020-09-29 22:49:58 +00:00
Matthew Dempsky
ad0ab812f8 cmd/compile: fix type checking of "make" arguments
As part of type checking make's arguments, we were converting untyped
float and complex constant arguments to integers. However, we were
doing this without concern for whether the argument was a declared
constant. Thus a call like "make([]T, n)" could change n from an
untyped float or untyped complex to an untyped integer.

The fix here is to simply change checkmake to not call SetVal, which
will be handled by defaultlit anyway. However, we also need to
properly return the defaultlit result value to the caller, so
checkmake's *Node parameter is also changed to **Node.

Fixes #41680.

Change-Id: I858927a052f384ec38684570d37b10a6906961f7
Reviewed-on: https://go-review.googlesource.com/c/go/+/257966
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
2020-09-28 20:54:13 +00:00
Lynn Boger
a424f6e45e cmd/asm,cmd/compile,cmd/internal/obj/ppc64: add extswsli support on power9
This adds support for the extswsli instruction which combines
extsw followed by a shift.

New benchmark demonstrates the improvement:
name      old time/op  new time/op  delta
ExtShift  1.34µs ± 0%  1.30µs ± 0%  -3.15%  (p=0.057 n=4+3)

Change-Id: I21b410676fdf15d20e0cbbaa75d7c6dcd3bbb7b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/257017
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <carlos.seo@gmail.com>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
2020-09-28 18:13:48 +00:00
Alberto Donizetti
e572218d12 cmd/compile: fix escape reason for MAKESLICE with no cap
When explaining why the slice from a make() call escapes for the -m -m
message, we print "non-const size" if any one of Isconst(n.Left) and
Isconst(n.Right) return false; but for OMAKESLICE nodes with no cap,
n.Right is nil, so Isconst(n.Right, CTINT) will be always false.

Only call Isconst on n.Right if it's not nil.

Fixes #41635

Change-Id: I8729801a9b234b68ae40adad64d66fa7653adf09
Reviewed-on: https://go-review.googlesource.com/c/go/+/257641
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
2020-09-28 06:38:58 +00:00
Keith Randall
2333c6299f runtime: use old capacity to decide on append growth regime
We grow the backing store on append by 2x for small sizes and 1.25x
for large sizes. The threshold we use for picking the growth factor
used to depend on the old length, not the old capacity. That's kind of
unfortunate, because then doing append(s, 0, 0) and append(append(s,
0), 0) do different things. (If s has one more spot available, then
the former expression chooses its growth based on len(s) and the
latter on len(s)+1.)  If we instead use the old capacity, we get more
consistent behavior. (Both expressions use len(s)+1 == cap(s) to
decide.)

Fixes #41239

Change-Id: I40686471d256edd72ec92aef973a89b52e235d4b
Reviewed-on: https://go-review.googlesource.com/c/go/+/257338
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2020-09-25 03:59:54 +00:00
Cuong Manh Le
23573d0ea2 cmd/compile: clearer error when non-bool used as "||" and "&&" operand
Fixes #41500

Change-Id: I658d8921b7769b6e4288ca781cbdca5ff14a84ee
Reviewed-on: https://go-review.googlesource.com/c/go/+/255899
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2020-09-22 04:13:13 +00:00
Cuong Manh Le
df73945fd2 cmd/compile: make error message involving variadic calls clearer
Fixes #41440

Change-Id: I2fbac72ae3b76bca32cdeaee678a19af3595d116
Reviewed-on: https://go-review.googlesource.com/c/go/+/255241
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2020-09-18 07:54:47 +00:00
Matthew Dempsky
ddd35f8d71 cmd/compile: more comprehensive tests for #24991
The revised test now checks that unsafe-uintptr correctly works for
variadic uintptr parameters too, and the CL corrects the code so this
code compiles again.

The pointers are still not kept alive properly. That will be fixed by
a followup CL. But this CL at least allows programs not affected by
that to build again.

Updates #24991.
Updates #41460.

Change-Id: If4c39167b6055e602213fb7522c4f527c43ebda9
Reviewed-on: https://go-review.googlesource.com/c/go/+/255877
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2020-09-18 05:12:59 +00:00
Keith Randall
22053790fa cmd/compile: propagate go:notinheap implicitly
//go:notinheap
type T int

type U T

We already correctly propagate the notinheap-ness of T to U.  But we
have an assertion in the typechecker that if there's no explicit
//go:notinheap associated with U, then report an error. Get rid of
that error so that implicit propagation is allowed.

Adjust the tests so that we make sure that uses of types like U
do correctly report an error when U is used in a context that might
cause a Go heap allocation.

Fixes #41451

Update #40954
Update #41432

Change-Id: I1692bc7cceff21ebb3f557f3748812a40887118d
Reviewed-on: https://go-review.googlesource.com/c/go/+/255637
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2020-09-17 19:35:53 +00:00
Lynn Boger
967465da29 cmd/compile: use combined shifts to improve array addressing on ppc64x
This change adds rules to find pairs of instructions that can
be combined into a single shifts. These instruction sequences
are common in array addressing within loops. Improvements can
be seen in many crypto packages and the hash packages.

These are based on the extended mnemonics found in the ISA
sections C.8.1 and C.8.2.

Some rules in PPC64.rules were moved because the ordering prevented
some matching.

The following results were generated on power9.

hash/crc32:
    CRC32/poly=Koopman/size=40/align=0          195ns ± 0%     163ns ± 0%  -16.41%
    CRC32/poly=Koopman/size=40/align=1          200ns ± 0%     163ns ± 0%  -18.50%
    CRC32/poly=Koopman/size=512/align=0        1.98µs ± 0%    1.67µs ± 0%  -15.46%
    CRC32/poly=Koopman/size=512/align=1        1.98µs ± 0%    1.69µs ± 0%  -14.80%
    CRC32/poly=Koopman/size=1kB/align=0        3.90µs ± 0%    3.31µs ± 0%  -15.27%
    CRC32/poly=Koopman/size=1kB/align=1        3.85µs ± 0%    3.31µs ± 0%  -14.15%
    CRC32/poly=Koopman/size=4kB/align=0        15.3µs ± 0%    13.1µs ± 0%  -14.22%
    CRC32/poly=Koopman/size=4kB/align=1        15.4µs ± 0%    13.1µs ± 0%  -14.79%
    CRC32/poly=Koopman/size=32kB/align=0        137µs ± 0%     105µs ± 0%  -23.56%
    CRC32/poly=Koopman/size=32kB/align=1        137µs ± 0%     105µs ± 0%  -23.53%

crypto/rc4:
    RC4_128    733ns ± 0%    650ns ± 0%  -11.32%  (p=1.000 n=1+1)
    RC4_1K    5.80µs ± 0%   5.17µs ± 0%  -10.89%  (p=1.000 n=1+1)
    RC4_8K    45.7µs ± 0%   40.8µs ± 0%  -10.73%  (p=1.000 n=1+1)

crypto/sha1:
    Hash8Bytes       635ns ± 0%     613ns ± 0%   -3.46%  (p=1.000 n=1+1)
    Hash320Bytes    2.30µs ± 0%    2.18µs ± 0%   -5.38%  (p=1.000 n=1+1)
    Hash1K          5.88µs ± 0%    5.38µs ± 0%   -8.62%  (p=1.000 n=1+1)
    Hash8K          42.0µs ± 0%    37.9µs ± 0%   -9.75%  (p=1.000 n=1+1)

There are other improvements found in golang.org/x/crypto which are all in the
range of 5-15%.

Change-Id: I193471fbcf674151ffe2edab212799d9b08dfb8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/252097
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2020-09-17 12:37:40 +00:00
Alberto Donizetti
7ee35cb301 cmd/compile: be more specific in cannot assign errors
"cannot assign to" compiler errors are very laconic: they never
explain why the lhs cannot be assigned to (with one exception, when
assigning to a struct field in a map).

This change makes them a little more specific, in two more cases: when
assigning to a string, or to a const; by giving a very brief reason
why the lhs cannot be assigned to.

Change-Id: I244cca7fc3c3814e00e0ccadeec62f747c293979
Reviewed-on: https://go-review.googlesource.com/c/go/+/255199
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2020-09-16 20:04:58 +00:00
Keith Randall
37f261010f cmd/compile: make go:notinheap error message friendlier for cgo
Update #40954

Change-Id: Ifaab7349631ccb12fc892882bbdf7f0ebf3d845f
Reviewed-on: https://go-review.googlesource.com/c/go/+/251158
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2020-09-16 17:28:13 +00:00
Keith Randall
42b023d7b9 cmd/cgo: use go:notinheap for anonymous structs
They can't reasonably be allocated on the heap. Not a huge deal, but
it has an interesting and useful side effect.

After CL 249917, the compiler and runtime treat pointers to
go:notinheap types as uintptrs instead of real pointers (no write
barrier, not processed during stack scanning, ...). That feature is
exactly what we want for cgo to fix #40954. All the cases we have of
pointers declared in C, but which might actually be filled with
non-pointer data, are of this form (JNI's jobject heirarch, Darwin's
CFType heirarchy, ...).

Fixes #40954

Change-Id: I44a3b9bc2513d4287107e39d0cbbd0efd46a3aae
Reviewed-on: https://go-review.googlesource.com/c/go/+/250940
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2020-09-16 17:26:46 +00:00
Keith Randall
4f915911e8 cmd/compile: allow aliases to go:notinheap types
The alias doesn't need to be marked go:notinheap. It gets its
notinheap-ness from the target type.

Without this change, the type alias test in the notinheap.go file
generates these two errors:

notinheap.go:62: misplaced compiler directive
notinheap.go:63: type nih must be go:notinheap

The first is a result of go:notinheap pragmas not applying
to type alias declarations.
The second is the result of then trying to match the notinheap-ness
of the alias and the target type.

Add a few more go:notinheap tests while we are here.

Update #40954

Change-Id: I067ec47698df6e9e593e080d67796fd05a1d480f
Reviewed-on: https://go-review.googlesource.com/c/go/+/250939
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2020-09-16 17:24:33 +00:00
Matthew Dempsky
bae9cf6517 test: fix inline.go to pass linux-amd64-noopt
Updates #33485.

Change-Id: I3330860cdff1e9797466a7630bcdb7792c465b06
Reviewed-on: https://go-review.googlesource.com/c/go/+/254938
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2020-09-15 02:52:12 +00:00
Matthew Dempsky
f4936d09fd cmd/compile: call fninit earlier
This allows the global initializers function to go through normal
mid-end optimizations (e.g., inlining, escape analysis) like any other
function.

Updates #33485.

Change-Id: I9bcfe98b8628d1aca09b4c238d8d3b74c69010a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/254839
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
2020-09-14 23:42:44 +00:00
Cuong Manh Le
afb5fca25a test: fix flaky test for issue24491
runtime.GC() doesn't guarantee the finalizer has run, so use a channel
instead to make sure finalizer was run in call to "after()".

Fixes #41361

Change-Id: I69c801e29aea49757ea72c52e8db13239de19ddc
Reviewed-on: https://go-review.googlesource.com/c/go/+/254401
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2020-09-13 07:54:42 +00:00
Cuong Manh Le
1f45216694 cmd/compile: attach OVARLIVE nodes to OCALLxxx
So we can insert theses OVARLIVE nodes right after OpStaticCall in SSA.

This helps fixing issue that unsafe-uintptr arguments are not kept alive
during return statement, or can be kept alive longer than expected.

Fixes #24491

Change-Id: Ic04a5d1bbb5c90dcfae65bd95cdd1da393a66800
Reviewed-on: https://go-review.googlesource.com/c/go/+/254397
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2020-09-13 04:35:22 +00:00
Cuong Manh Le
806f478499 cmd/compile: don't report not enough args error if call is undefined
Fixes #38745

Change-Id: I2fbd8b512a8cf911b81a087162c74416116efea5
Reviewed-on: https://go-review.googlesource.com/c/go/+/253678
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2020-09-12 08:50:45 +00:00
Cuong Manh Le
2c95e3a6a8 cmd/compile: use clearer error message for stuct literal
This CL changes "T literal.M" error message to "T{...}.M". It's clearer
expression and focusing user on actual issue.

Updates #38745

Change-Id: I84b455a86742f37e0bde5bf390aa02984eecc3c9
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2020-09-12 08:31:49 +00:00
Cuong Manh Le
bdb480fd62 cmd/compile: fix mishandling of unsafe-uintptr arguments in go/defer
Currently, the statement:

	go g(uintptr(f()))

gets rewritten into:

	tmp := f()
	newproc(8, g, uintptr(tmp))
	runtime.KeepAlive(tmp)

which doesn't guarantee that tmp is still alive by time the g call is
scheduled to run.

This CL fixes the issue, by wrapping g call in a closure:

	go func(p unsafe.Pointer) {
		g(uintptr(p))
	}(f())

then this will be rewritten into:

	tmp := f()
	go func(p unsafe.Pointer) {
		g(uintptr(p))
		runtime.KeepAlive(p)
	}(tmp)
	runtime.KeepAlive(tmp)  // superfluous, but harmless

So the unsafe.Pointer p will be kept alive at the time g call runs.

Updates #24491

Change-Id: Ic10821251cbb1b0073daec92b82a866c6ebaf567
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2020-09-09 07:50:01 +00:00
Cuong Manh Le
dc025c0f9b cmd/compile: handle ODDD in exprformat
Fixes #41247

Change-Id: Iaa9502cc610e2cc64be5dfd91ba3187f86f87cbd
Reviewed-on: https://go-review.googlesource.com/c/go/+/252942
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2020-09-07 05:44:53 +00:00
Cuong Manh Le
27a30186ab cmd/compile,runtime: skip zero'ing order array for select statements
The order array was zero initialized by the compiler, but ends up being
overwritten by the runtime anyway.

So let the runtime takes full responsibility for initializing, save us
one instruction per select.

Fixes #40399

Change-Id: Iec1eca27ad7180d4fcb3cc9ef97348206b7fe6b8
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2020-08-29 08:02:52 +00:00
Ian Lance Taylor
49bae98495 test: add test that gccgo failed to compile
For #38125

Change-Id: Id6ef10d74f0f9dbad2851531e0fe019cd145cf7c
Reviewed-on: https://go-review.googlesource.com/c/go/+/251168
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2020-08-28 23:43:22 +00:00
zdjones
a58a8d2e97 test: document specifying individual test files as operands
The current command will run this entire set of tests, which takes a
noticeable amount of time. Contributors may wish to run only a subset of
these tests to save time/compute (e.g. when iterating on a CL that
failed tests in that subset). Listing file(s) as operands to the command
will run only those tests.

Change-Id: I1874c43681a594190bc40b61cee0b8d321be73f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/242997
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2020-08-28 21:23:32 +00:00
Xiangdong Ji
55cf84b077 cmd/compile: Install testcases for flag constant Ops
Flag constant Ops on arm and arm64 are under refactoring, this change adds
a couple of testcases that verify the behavior of 'noov' branches.

Updates #39505
Updates #38740
Updates #39303
Change-Id: I493344b52276900cd296c32da494d72932dfc9be
Reviewed-on: https://go-review.googlesource.com/c/go/+/238677
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2020-08-28 16:40:32 +00:00
Keith Randall
42fd1306ce cmd/compile: clean up equality generation
We're using sort.SliceStable, so no need to keep track of indexes as well.

Use a more robust test for whether a node is a call.

Add a test that we're actually reordering comparisons. This test fails
without the alg.go changes in this CL because eqstring uses OCALLFUNC
instead of OCALL for its data comparisons.

Update #8606

Change-Id: Ieeec33434c72e3aa328deb11cc415cfda05632e2
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2020-08-27 23:25:58 +00:00
Paul E. Murphy
7615b20d06 cmd/compile: generate subfic on ppc64
This merges an lis + subf into subfic, and for 32b constants
lwa + subf into oris + ori + subf.

The carry bit is no longer used in code generation, therefore
I think we can clobber it as needed.  Note, lowered borrow/carry
arithmetic is self-contained and thus is not affected.

A few extra rules are added to ensure early transformations to
SUBFCconst don't trip up earlier rules, fold constant operations,
or otherwise simplify lowering.  Likewise, tests are added to
ensure all rules are hit.  Generic constant folding catches
trivial cases, however some lowering rules insert arithmetic
which can introduce new opportunities (e.g BitLen or Slicemask).

I couldn't find a specific benchmark to demonstrate noteworthy
improvements, but this is generating subfic in many of the default
bent test binaries, so we are at least saving a little code space.

Change-Id: Iad7c6e5767eaa9dc24dc1c989bd1c8cfe1982012
Reviewed-on: https://go-review.googlesource.com/c/go/+/249461
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2020-08-27 20:10:15 +00:00
Cuong Manh Le
d3f6e2f300 cmd/compile: report error for unexported name only once
Fixes #22921

Change-Id: If29bd962335ac7676ea4f379727db3d55ae1bf8e
Reviewed-on: https://go-review.googlesource.com/c/go/+/250177
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2020-08-25 16:06:36 +00:00
Keith Randall
d9a6bdf7ef cmd/compile: don't allow go:notinheap on the heap or stack
Right now we just prevent such types from being on the heap. This CL
makes it so they cannot appear on the stack either. The distinction
between heap and stack is pretty vague at the language level (e.g. it
is affected by -N), and we don't need the flexibility anyway.

Once go:notinheap types cannot be in either place, we don't need to
consider pointers to such types to be pointers, at least according to
the garbage collector and stack copying. (This is the big win of this
CL, in my opinion.)

The distinction between HasPointers and HasHeapPointer no longer
exists. There is only HasPointers.

This CL is cleanup before possible use of go:notinheap to fix #40954.

Update #13386

Change-Id: Ibd895aadf001c0385078a6d4809c3f374991231a
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2020-08-25 01:46:05 +00:00
fanzha02
d556c251a1 cmd/compile: add more generic rewrite rules to reassociate (op (op y C) x|C)
With this patch, opt pass can expose more obvious constant-folding
opportunites.

Example:
func test(i int) int {return (i+8)-(i+4)}

The previous version:
  MOVD	"".i(FP), R0
  ADD	$8, R0, R1
  ADD	$4, R0, R0
  SUB	R0, R1, R0
  MOVD	R0, "".~r1+8(FP)
  RET	(R30)

The optimized version:
  MOVD	$4, R0
  MOVD	R0, "".~r1+8(FP)
  RET	(R30)

This patch removes some existing reassociation rules, such as "x+(z-C)",
because the current generic rewrite rules will canonicalize "x-const"
to "x+(-const)", making "x+(z-C)" equal to "x+(z+(-C))".

This patch also adds test cases.

Change-Id: I857108ba0b5fcc18a879eeab38e2551bc4277797
Reviewed-on: https://go-review.googlesource.com/c/go/+/237137
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2020-08-24 14:52:54 +00:00
Cuong Manh Le
0c3bf27b97 test: remove nacl checking condition
go1.14 drop nacl support, as go1.15 was released, go1.13 is not
supported anymore, nacl is absolutely gone.

Change-Id: I05efb46891ec875b08da8f2996751a8e9cb57d0c
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2020-08-23 05:24:15 +00:00
Agniva De Sarker
8acbe4c0b3 cmd/compile: optimize unsigned comparisons with 0/1 on wasm
Updates #21439

Change-Id: I0fbcde6e0c2fc368fe686b271670f9d8be4a7900
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2020-08-22 12:35:47 +00:00
Matthew Dempsky
e94544cf01 cmd/compile: fix checkptr handling of &^
checkptr has code to recognize &^ expressions, but it didn't take into
account that "p &^ x" gets rewritten to "p & ^x" during walk, which
resulted in false positive diagnostics.

This CL changes walkexpr to mark OANDNOT expressions with Implicit
when they're rewritten to OAND, so that walkCheckPtrArithmetic can
still recognize them later.

It would be slightly more idiomatic to instead mark the OBITNOT
expression as Implicit (as it's a compiler-generated Node), but the
OBITNOT expression might get constant folded. It's not worth the extra
complexity/subtlety of relying on n.Right.Orig, so we set Implicit on
the OAND node instead.

To atone for this transgression, I add documentation for nodeImplicit.

Fixes #40917.

Change-Id: I386304171ad299c530e151e5924f179e9a5fd5b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/249477
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2020-08-20 17:48:29 +00:00
diaxu01
01aad9ea93 cmd/compile: Optimize ARM64's code with EON
This patch fuses pattern '(MVN (XOR x y))' into '(EON x y)'.

Change-Id: I269c98ce198d51a4945ce8bd0e1024acbd1b7609
Reviewed-on: https://go-review.googlesource.com/c/go/+/239638
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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2020-08-19 16:47:14 +00:00
Cuong Manh Le
ac875bc923 cmd/compile: don't bother to declare closure inside redeclared func
Fixes #17758

Change-Id: I75f5dc5be85fd8a6791ac89dfc0681be759cca36
Reviewed-on: https://go-review.googlesource.com/c/go/+/248517
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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2020-08-19 02:25:13 +00:00
Paul E. Murphy
e7c7ce646f cmd/compile: combine multiply/add into maddld on ppc64le/power9
Add a new lowering rule to match and replace such instances
with the MADDLD instruction available on power9 where
possible.

Likewise, this plumbs in a new ppc64 ssa opcode to house
the newly generated MADDLD instructions.

When testing ed25519, this reduced binary size by 936B.
Similarly, MADDLD combination occcurs in a few other less
obvious cases such as division by constant.

Testing of golang.org/x/crypto/ed25519 shows non-trivial
speedup during keygeneration:

name           old time/op  new time/op  delta
KeyGeneration  65.2µs ± 0%  63.1µs ± 0%  -3.19%
Signing        64.3µs ± 0%  64.4µs ± 0%  +0.16%
Verification    147µs ± 0%   147µs ± 0%  +0.11%

Similarly, this test binary has shrunk by 66488B.

Change-Id: I077aeda7943119b41f07e4e62e44a648f16e4ad0
Reviewed-on: https://go-review.googlesource.com/c/go/+/248723
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
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2020-08-18 21:09:30 +00:00
Michael Munday
6e876f1985 cmd/compile: clean up and optimize s390x multiplication rules
Some of the existing optimizations aren't triggered because they
are handled by the generic rules so this CL removes them. Also
some constraints were copied without much thought from the amd64
rules and they don't make sense on s390x, so we remove those
constraints.

Finally, add a 'multiply by the sum of two powers of two'
optimization. This makes sense on s390x as shifts are low latency
and can also sometimes be optimized further (especially if we add
support for RISBG instructions).

name                   old time/op  new time/op  delta
IntMulByConst/3-8      1.70ns ±11%  1.10ns ± 5%  -35.26%  (p=0.000 n=10+10)
IntMulByConst/5-8      1.64ns ± 7%  1.10ns ± 4%  -32.94%  (p=0.000 n=10+9)
IntMulByConst/12-8     1.65ns ± 6%  1.20ns ± 4%  -27.16%  (p=0.000 n=10+9)
IntMulByConst/120-8    1.66ns ± 4%  1.22ns ±13%  -26.43%  (p=0.000 n=10+10)
IntMulByConst/-120-8   1.65ns ± 7%  1.19ns ± 4%  -28.06%  (p=0.000 n=9+10)
IntMulByConst/65537-8  0.86ns ± 9%  1.12ns ±12%  +30.41%  (p=0.000 n=10+10)
IntMulByConst/65538-8  1.65ns ± 5%  1.23ns ± 5%  -25.11%  (p=0.000 n=10+10)

Change-Id: Ib196e6bff1e97febfd266134d0a2b2a62897989f
Reviewed-on: https://go-review.googlesource.com/c/go/+/248937
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2020-08-18 15:39:44 +00:00
Junchen Li
06337823ef cmd/compile: optimize unsigned comparisons to 0/1 on arm64
For an unsigned integer, it's useful to convert its order test with 0/1
to its equality test with 0. We can save a comparison instruction that
followed by a conditional branch on arm64 since it supports
compare-with-zero-and-branch instructions. For example,

  if x > 0 { ... } else { ... }

the original version:
  CMP $0, R0
  BLS 9

the optimized version:
  CBZ R0, 8

Updates #21439

Change-Id: Id1de6f865f6aa72c5d45b29f7894818857288425
Reviewed-on: https://go-review.googlesource.com/c/go/+/246857
Reviewed-by: Keith Randall <khr@golang.org>
2020-08-18 04:09:13 +00:00
Keith Randall
ef9c8a38ad cmd/compile: don't rewrite (CMP (AND x y) 0) to TEST if AND has other uses
If the AND has other uses, we end up saving an argument to the AND
in another register, so we can use it for the TEST. No point in doing that.

Change-Id: I73444a6aeddd6f55e2328ce04d77c3e6cf4a83e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/241280
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Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
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2020-08-17 22:00:44 +00:00
Junchen Li
e30fbe3757 cmd/compile: optimize unsigned comparisons to 0
There are some architecture-independent rules in #21439, since an
unsigned integer >= 0 is always true and < 0 is always false. This CL
adds these optimizations to generic rules.

Updates #21439

Change-Id: Iec7e3040b761ecb1e60908f764815fdd9bc62495
Reviewed-on: https://go-review.googlesource.com/c/go/+/246617
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2020-08-17 20:06:35 +00:00
Tobias Klauser
dc12d5b0f5 all: add empty line between copyright header and package clause
Makes sure the copyright notice is not interpreted as the package level
godoc.

Change-Id: I2afce7c9d620f19d51ec1438b1d0db1774b57146
Reviewed-on: https://go-review.googlesource.com/c/go/+/248760
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2020-08-17 09:45:44 +00:00
Matthew Dempsky
69d34e2c69 test: bump array size in fixedbugs/issue39292.go
The previous array length was large enough to exceed
maxImplicitStackSize on 64-bit architectures, but not on 32-bit
architectures.

Fixes #40808.

Change-Id: I69e9abb447454b2e7875ba503a0cb772e965ae31
Reviewed-on: https://go-review.googlesource.com/c/go/+/248680
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2020-08-15 04:45:34 +00:00
Cuong Manh Le
948d324f7d cmd/compile: add failing test case for #24305
Updates #24305

Change-Id: Ib0b093e33004a978467cdd1e77186798392d4eca
Reviewed-on: https://go-review.googlesource.com/c/go/+/248217
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2020-08-15 03:09:52 +00:00
Cuong Manh Le
82c45eb681 cmd/compile: handle OCLOSURE/OCALLPART in mustHeapAlloc check
Currently, generated struct wrapper for closure is not handled in
mustHeapAlloc. That causes compiler crashes when the wrapper struct
is too large for stack, and must be heap allocated instead.

Fixes #39292

Change-Id: I14c1e591681d9d92317bb2396d6cf5207aa93e08
Reviewed-on: https://go-review.googlesource.com/c/go/+/244917
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2020-08-15 03:09:35 +00:00
Cuong Manh Le
0031fa80a3 cmd/compile: another fix initializing blank fields in struct literal
CL 230121 fixed the bug that struct literal blank fields type array/struct
can not be initialized. But it still misses some cases when an expression
causes "candiscard(value)" return false. When these happen, we recursively
call fixedlit with "var_" set to "_", and hit the bug again.

To fix it, just making splitnode return "nblank" whenever "var_" is "nblank".

Fixes #38905

Change-Id: I281941b388acbd551a4d8ca1a235477f8d26fb6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/232617
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2020-08-15 03:09:21 +00:00
Ian Lance Taylor
12d40adac4 test: add test for conversion of untyped bool to interface
gccgo miscompiled this case.

Updates #40152

Change-Id: I8448c155e802e39d8fc7cda4930ce62cb6363ce5
Reviewed-on: https://go-review.googlesource.com/c/go/+/242000
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2020-08-15 01:43:18 +00:00
Ian Lance Taylor
6072d6ee3e test: add a test case that gccgo fails to compile
Change-Id: If36394e059cdae49834d26ad4ffdd3092a72a0b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/241997
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2020-08-15 01:42:57 +00:00
Ian Lance Taylor
f71444955a test: add test case that caused gccgo undefined symbol reference
For #40252

Change-Id: Ie23d2789ca9b4b9081adb39ab64c80c412ad58ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/248637
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2020-08-15 00:23:28 +00:00
Keith Randall
32a84c99e1 cmd/compile: fix live variable computation for deferreturn
Taking the live variable set from the last return point is problematic.
See #40629 for details, but there may not be a return point, or it may
be before the final defer.

Additionally, keeping track of the last call as a *Value doesn't quite
work. If it is dead-code eliminated, the storage for the Value is reused
for some other random instruction. Its live variable information,
if it is available at all, is wrong.

Instead, just mark all the open-defer argument slots as live
throughout the function. (They are already zero-initialized.)

Fixes #40629

Change-Id: Ie456c7db3082d0de57eaa5234a0f32525a1cce13
Reviewed-on: https://go-review.googlesource.com/c/go/+/247522
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2020-08-14 21:49:36 +00:00
Josh Bleecher Snyder
cde5fd1c0f cmd/compile: correct type of CvtBoolToUint8 values
Fixes #40746

Change-Id: I539f07d1f958dacee87d846171a8889d03182d25
Reviewed-on: https://go-review.googlesource.com/c/go/+/248397
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2020-08-13 22:59:31 +00:00
Cholerae Hu
7f86080476 cmd/compile: don't addLocalInductiveFacts if there is no direct edge from if block to phi block
Currently in addLocalInductiveFacts, we only check whether
direct edge from if block to phi block exists. If not, the
following logic will treat the phi block as the first successor,
which is wrong.

This patch makes prove pass more conservative, so we disable
some cases in test/prove.go. We will do some optimization in
the following CL and enable these cases then.

Fixes #40367.

Change-Id: I27cf0248f3a82312a6f7dabe11c79a1a34cf5412
Reviewed-on: https://go-review.googlesource.com/c/go/+/244579
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2020-07-30 17:23:11 +00:00
Keith Randall
c4fed25553 cmd/compile: add floating point load+op operations to addressing modes pass
They were missed as part of the refactoring to use a separate
addressing modes pass.

Fixes #40426

Change-Id: Ie0418b2fac4ba1ffe720644ac918f6d728d5e420
Reviewed-on: https://go-review.googlesource.com/c/go/+/244859
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2020-07-27 18:24:32 +00:00
Alberto Donizetti
11f92e9dae cmd/compile: add test for fixed ICE on untyped conversion
The ICE reported as #33308 was fixed by a related CL; this change adds
a regression test with the crasher.

Fixes #33308

Change-Id: I3260075dbe3823b56b8825e6269e57a0fad185a6
Reviewed-on: https://go-review.googlesource.com/c/go/+/243458
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-07-20 18:18:56 +00:00
Keith Randall
3b2f67a597 cmd/compile: remove check that Zero's arg has the correct base type
It doesn't have to. The type in the aux field is authoritative.
There are cases involving casting from interface{} where pointers
have a placeholder pointer type (because the type is not known when
the IData op is generated).

The check was introduced in CL 13447.

Fixes #39459

Change-Id: Id77a57577806a271aeebd20bea5d92d08ee7aa6b
Reviewed-on: https://go-review.googlesource.com/c/go/+/239817
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2020-06-25 15:59:48 +00:00
Keith Randall
3dec253783 reflect: zero stack slots before writing to them with write barriers
reflect.assignTo writes to the target using write barriers. Make sure
that the memory it is writing to is zeroed, so the write barrier does
not read pointers from uninitialized memory.

Fixes #39541

Change-Id: Ia64b2cacc193bffd0c1396bbce1dfb8182d4905b
Reviewed-on: https://go-review.googlesource.com/c/go/+/238760
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2020-06-19 02:11:35 +00:00
Michael Munday
377c1536f5 cmd/compile: mark s390x int <-> float conversions as clobbering flags
These conversion instructions set the condition code and so should
be marked as clobbering flags.

Fixes #39651.

Change-Id: I91cc9687ea70ef0551bb3139c1875071c349d43e
Reviewed-on: https://go-review.googlesource.com/c/go/+/238628
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2020-06-18 16:36:16 +00:00
Keith Randall
8c8045fd38 cmd/compile: fix ordering problems in struct equality
Make sure that if a field comparison might panic, we evaluate
(and short circuit if not equal) all previous fields, and don't
evaluate any subsequent fields.

Add a bunch more tests to the equality+panic checker.

Update #8606

Change-Id: I6a159bbc8da5b2b7ee835c0cd1fc565575b58c46
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2020-06-15 18:03:08 +00:00
Michael Munday
ac743dea8e cmd/compile: always tighten and de-duplicate tuple selectors
The scheduler assumes two special invariants that apply to tuple
selectors (Select0 and Select1 ops):

  1. There is only one tuple selector of each type per generator.
  2. Tuple selectors and generators reside in the same block.

Prior to this CL the assumption was that these invariants would
only be broken by the CSE pass. The CSE pass therefore contained
code to move and de-duplicate selectors to fix these invariants.

However it is also possible to write relatively basic optimization
rules that cause these invariants to be broken. For example:

  (A (Select0 (B))) -> (Select1 (B))

This rule could result in the newly added selector (Select1) being
in a different block to the tuple generator (see issue #38356). It
could also result in duplicate selectors if this rule matches
multiple times for the same tuple generator (see issue #39472).

The CSE pass will 'fix' these invariants. However it will only do
so when optimizations are enabled (since disabling optimizations
disables the CSE pass).

This CL moves the CSE tuple selector fixup code into its own pass
and makes it mandatory even when optimizations are disabled. This
allows tuple selectors to be treated like normal ops for most of
the compilation pipeline until after the new pass has run, at which
point we need to be careful to maintain the invariant again.

Fixes #39472.

Change-Id: Ia3f79e09d9c65ac95f897ce37e967ee1258a080b
Reviewed-on: https://go-review.googlesource.com/c/go/+/237118
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2020-06-10 14:55:29 +00:00
Xiangdong Ji
e031318ca6 cmd/compile: ARM comparisons with 0 incorrect on overflow
Some ARM rewriting rules convert 'comparing to zero' conditions of if
statements to a simplified version utilizing CMN and CMP instructions to
branch over condition flags, in order to save one Add or Sub caculation.

Such optimizations lead to wrong branching in case an overflow/underflow
occurs when executing CMN or CMP.

Fix the issue by introducing new block opcodes that don't honor the
overflow/underflow flag:

  Block-Op         Meaning                   ARM condition codes
  1. LTnoov        less than                 MI
  2. GEnoov        greater than or equal     PL
  3. LEnoov        less than or equal        MI || EQ
  4. GTnoov        greater than              NEQ & PL

The patch also adds a few test cases to cover scenarios that are specific
to ARM and fine-tunes the code generation tests for 'x-const'.

For more details please refer to the previous fix on 64-bit ARM:
  https://go-review.googlesource.com/c/go/+/233097

Go1 perf, 'old' is the non-optimized version, that is removing all concerned
rewriting rules.

name                     old time/op    new time/op     delta
BinaryTree17-8              7.73s ± 0%      7.81s ± 0%  +0.97%  (p=0.000 n=7+8)
Fannkuch11-8                7.06s ± 0%      7.00s ± 0%  -0.83%  (p=0.000 n=8+8)
FmtFprintfEmpty-8           181ns ± 1%      183ns ± 1%  +1.31%  (p=0.001 n=8+8)
FmtFprintfString-8          319ns ± 1%      325ns ± 2%  +1.71%  (p=0.009 n=7+8)
FmtFprintfInt-8             358ns ± 1%      359ns ± 1%    ~     (p=0.293 n=7+7)
FmtFprintfIntInt-8          459ns ± 3%      456ns ± 1%    ~     (p=0.869 n=8+8)
FmtFprintfPrefixedInt-8     535ns ± 4%      538ns ± 4%    ~     (p=0.572 n=8+8)
FmtFprintfFloat-8          1.01µs ± 2%     1.01µs ± 2%    ~     (p=0.625 n=8+8)
FmtManyArgs-8              1.93µs ± 2%     1.93µs ± 1%    ~     (p=0.979 n=8+7)
GobDecode-8                16.1ms ± 1%     16.5ms ± 1%  +2.32%  (p=0.000 n=8+8)
GobEncode-8                15.9ms ± 0%     15.8ms ± 1%  -1.00%  (p=0.000 n=8+7)
Gzip-8                      690ms ± 1%      670ms ± 0%  -2.90%  (p=0.000 n=8+8)
Gunzip-8                    109ms ± 1%      109ms ± 1%    ~     (p=0.694 n=7+8)
HTTPClientServer-8          149µs ± 3%      146µs ± 2%  -1.70%  (p=0.028 n=8+8)
JSONEncode-8               50.5ms ± 1%     49.2ms ± 0%  -2.60%  (p=0.001 n=7+7)
JSONDecode-8                135ms ± 2%      137ms ± 1%    ~     (p=0.054 n=8+7)
Mandelbrot200-8             951ms ± 0%      952ms ± 0%    ~     (p=0.852 n=6+8)
GoParse-8                  9.47ms ± 1%     9.66ms ± 1%  +2.01%  (p=0.000 n=8+8)
RegexpMatchEasy0_32-8       288ns ± 2%      277ns ± 2%  -3.61%  (p=0.000 n=8+8)
RegexpMatchEasy0_1K-8      1.66µs ± 1%     1.69µs ± 2%  +2.21%  (p=0.001 n=7+7)
RegexpMatchEasy1_32-8       334ns ± 1%      305ns ± 2%  -8.86%  (p=0.000 n=8+8)
RegexpMatchEasy1_1K-8      2.14µs ± 2%     2.15µs ± 0%    ~     (p=0.099 n=8+8)
RegexpMatchMedium_32-8     13.3ns ± 1%     13.3ns ± 0%    ~     (p=1.000 n=7+7)
RegexpMatchMedium_1K-8     81.1µs ± 3%     80.7µs ± 1%    ~     (p=0.955 n=7+8)
RegexpMatchHard_32-8       4.26µs ± 0%     4.26µs ± 0%    ~     (p=0.933 n=7+8)
RegexpMatchHard_1K-8        124µs ± 0%      124µs ± 0%  +0.31%  (p=0.000 n=8+8)
Revcomp-8                  14.7ms ± 2%     14.5ms ± 1%  -1.66%  (p=0.003 n=8+8)
Template-8                  197ms ± 2%      200ms ± 3%  +1.62%  (p=0.021 n=8+8)
TimeParse-8                1.33µs ± 1%     1.30µs ± 1%  -1.86%  (p=0.002 n=8+8)
TimeFormat-8               3.04µs ± 1%     3.02µs ± 0%  -0.60%  (p=0.000 n=8+8)

name                     old speed      new speed       delta
GobDecode-8              47.6MB/s ± 1%   46.5MB/s ± 1%  -2.28%  (p=0.000 n=8+8)
GobEncode-8              48.1MB/s ± 0%   48.6MB/s ± 1%  +1.02%  (p=0.000 n=8+7)
Gzip-8                   28.1MB/s ± 1%   29.0MB/s ± 0%  +2.97%  (p=0.000 n=8+8)
Gunzip-8                  178MB/s ± 1%    179MB/s ± 2%    ~     (p=0.694 n=7+8)
JSONEncode-8             38.4MB/s ± 1%   39.4MB/s ± 0%  +2.67%  (p=0.001 n=7+7)
JSONDecode-8             14.3MB/s ± 2%   14.2MB/s ± 1%  -0.81%  (p=0.043 n=8+7)
GoParse-8                6.12MB/s ± 1%   5.99MB/s ± 1%  -2.00%  (p=0.000 n=8+8)
RegexpMatchEasy0_32-8     111MB/s ± 2%    115MB/s ± 2%  +3.77%  (p=0.000 n=8+8)
RegexpMatchEasy0_1K-8     618MB/s ± 1%    604MB/s ± 2%  -2.16%  (p=0.001 n=7+7)
RegexpMatchEasy1_32-8    95.7MB/s ± 1%  105.1MB/s ± 2%  +9.76%  (p=0.000 n=8+8)
RegexpMatchEasy1_1K-8     479MB/s ± 2%    477MB/s ± 0%    ~     (p=0.105 n=8+8)
RegexpMatchMedium_32-8   75.2MB/s ± 1%   75.2MB/s ± 0%    ~     (p=0.247 n=7+7)
RegexpMatchMedium_1K-8   12.6MB/s ± 3%   12.7MB/s ± 1%    ~     (p=0.538 n=7+8)
RegexpMatchHard_32-8     7.52MB/s ± 0%   7.52MB/s ± 0%    ~     (p=0.968 n=7+8)
RegexpMatchHard_1K-8     8.26MB/s ± 0%   8.24MB/s ± 0%  -0.30%  (p=0.001 n=8+8)
Revcomp-8                 173MB/s ± 2%    176MB/s ± 1%  +1.68%  (p=0.003 n=8+8)
Template-8               9.85MB/s ± 2%   9.69MB/s ± 3%  -1.59%  (p=0.021 n=8+8)

Fixes   #39303
Updates #38740

Change-Id: I0a5f87bfda679f66414c0041ace2ca2e28363f36
Reviewed-on: https://go-review.googlesource.com/c/go/+/236637
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2020-06-09 15:50:33 +00:00
Dmitri Shuralyov
ee379d2b08 all: treat all files as binary, but check in .bat with CRLF
This is a followup to CL 96495.

It should be simpler and more robust to achieve .bat files having
CRLF line endings by treating it as a binary file, like all other
files, and checking it in with the desired CRLF line endings.

A test is used to check the entire Go tree, short of directories
starting with "." and named "testdata", for any .bat files that
have anything other than strict CRLF line endings. This will help
catch any accidental modifications to existing .bat files or check
ins of new .bat files.

Importantly, this is compatible with how Gerrit serves .tar.gz files,
making it so that CRLF line endings are preserved.

The Go project is supported on many different environments, some of
which may have limited git implementations available, or none at all.
Relying on fewer git features and special rules makes it easier to
have confidence in the exact content of all files. Additionally, Go
development started in Subversion, moved to Perforce, then Mercurial,
and now uses Git.¹ Reducing its reliance on git-specific features will
help if there will be another transition in the project's future.

There are only 5 .bat files in the entire Go source tree, so a new one
being added is a rare event, and we prefer to do things in Go instead.
We still have the option of improving the experience for developers by
adding a pre-commit converter for .bat files to the git-codereview tool.

¹ https://groups.google.com/d/msg/golang-dev/sckirqOWepg/YmyT7dWJiocJ

Fixes #39391.
For #37791.

Change-Id: I6e202216322872f0307ac96f1b8d3f57cb901e6b
Reviewed-on: https://go-review.googlesource.com/c/go/+/236437
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2020-06-08 15:31:43 +00:00
Keith Randall
f72d7cfc8f cmd/compile: add interface equality tests
Add interfaces which differ in type. Those used so far only
differ in value, not type.

These additional tests are needed to generate a failure
before CL 236278 went in.

Update #8606

Change-Id: Icdb7647b1973c2fff7e5afe2bd8b8c1b384f583e
Reviewed-on: https://go-review.googlesource.com/c/go/+/236418
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-06-04 06:21:55 +00:00
Keith Randall
9984ef824c cmd/compile: test that equality is evaluated in order
Make sure that we compare fields of structs and elements of arrays in order,
with proper short-circuiting.

Update #8606

Change-Id: I0a66ad92ea0af7bcc56dfdb275dec2b8d7e8b4fe
Reviewed-on: https://go-review.googlesource.com/c/go/+/236147
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-06-03 19:07:55 +00:00
Richard Musiol
0452f9460f runtime: fix race condition between timer and event handler
This change fixes a race condition between beforeIdle waking up the
innermost event handler and a timer causing a different goroutine to
wake up at the exact same moment. This messes up the wasm event handling
and leads to memory corruption. The solution is to make beforeIdle
return the goroutine that must run next and have findrunnable pick
this goroutine without considering timers again.

Fixes #38093
Fixes #38574

Change-Id: Iffbe99411d25c2730953d1c8b0741fd892f8e540
Reviewed-on: https://go-review.googlesource.com/c/go/+/230178
Run-TryBot: Richard Musiol <neelance@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-05-31 18:35:04 +00:00
Xiangdong Ji
e8f5a33191 cmd/compile: fix incorrect rewriting to if condition
Some ARM64 rewriting rules convert 'comparing to zero' conditions of if
statements to a simplified version utilizing CMN and CMP instructions to
branch over condition flags, in order to save one Add or Sub caculation.

Such optimizations lead to wrong branching in case an overflow/underflow
occurs when executing CMN or CMP.

Fix the issue by introducing new block opcodes that don't honor the
overflow/underflow flag, in the following categories:

  Block-Op        Meaning                   ARM condition codes
  1. LTnoov        less than                 MI
  2. GEnoov        greater than or equal     PL
  3. LEnoov        less than or equal        MI || EQ
  4. GTnoov        greater than              NEQ & PL

The backend generates two consecutive branch instructions for 'LEnoov'
and 'GTnoov' to model their expected behavior. A slight change to 'gc'
and amd64/386 backends is made to unify the code generation.

Add a test 'TestCondRewrite' as justification, it covers 32 incorrect rules
identified on arm64, more might be needed on other arches, like 32-bit arm.

Add two benchmarks profiling the aforementioned category 1&2 and category
3&4 separetely, we expect the first two categories will show performance
improvement and the second will not result in visible regression compared with
the non-optimized version.

This change also updates TestFormats to support using %#x.

Examples exhibiting where does the issue come from:
  1: 'if x + 3 < 0' might be converted to:
  before:
    CMN $3, R0
    BGE <else branch> // wrong branch is taken if 'x+3' overflows
  after:
    CMN $3, R0
    BPL <else branch>

  2: 'if y - 3 > 0' might be converted to:
  before:
    CMP $3, R0
    BLE <else branch> // wrong branch is taken if 'y-3' underflows
  after:
    CMP $3, R0
    BMI <else branch>
    BEQ <else branch>

Benchmark data from different kinds of arm64 servers, 'old' is the non-optimized
version (not the parent commit), generally the optimization version outperforms.

S1:
name                    old time/op  new time/op  delta
CondRewrite/SoloJump  13.6ns ± 0%  12.9ns ± 0%  -5.15%  (p=0.000 n=10+10)
CondRewrite/CombJump  13.8ns ± 1%  12.9ns ± 0%  -6.32%  (p=0.000 n=10+10)

S2:
name                     old time/op  new time/op  delta
CondRewrite/SoloJump  11.6ns ± 0%  10.9ns ± 0%  -6.03%  (p=0.000 n=10+10)
CondRewrite/CombJump  11.4ns ± 0%  10.8ns ± 1%  -5.53%  (p=0.000 n=10+10)

S3:
name                     old time/op  new time/op  delta
CondRewrite/SoloJump  7.36ns ± 0%  7.50ns ± 0%  +1.79%  (p=0.000 n=9+10)
CondRewrite/CombJump  7.35ns ± 0%  7.75ns ± 0%  +5.51%  (p=0.000 n=8+9)

S4:
name                      old time/op  new time/op  delta
CondRewrite/SoloJump-224  11.5ns ± 1%  10.9ns ± 0%  -4.97%  (p=0.000 n=10+10)
CondRewrite/CombJump-224  11.9ns ± 0%  11.5ns ± 0%  -2.95%  (p=0.000 n=10+10)

S5:
name                     old time/op  new time/op  delta
CondRewrite/SoloJump  10.0ns ± 0%  10.0ns ± 0%  -0.45%  (p=0.000 n=9+10)
CondRewrite/CombJump  9.93ns ± 0%  9.77ns ± 0%  -1.53%  (p=0.000 n=10+9)

Go1 perf. data:

name                     old time/op    new time/op    delta
BinaryTree17              6.29s ± 1%     6.30s ± 1%    ~     (p=1.000 n=5+5)
Fannkuch11                5.40s ± 0%     5.40s ± 0%    ~     (p=0.841 n=5+5)
FmtFprintfEmpty          97.9ns ± 0%    98.9ns ± 3%    ~     (p=0.937 n=4+5)
FmtFprintfString          171ns ± 3%     171ns ± 2%    ~     (p=0.754 n=5+5)
FmtFprintfInt             212ns ± 0%     217ns ± 6%  +2.55%  (p=0.008 n=5+5)
FmtFprintfIntInt          296ns ± 1%     297ns ± 2%    ~     (p=0.516 n=5+5)
FmtFprintfPrefixedInt     371ns ± 2%     374ns ± 7%    ~     (p=1.000 n=5+5)
FmtFprintfFloat           435ns ± 1%     439ns ± 2%    ~     (p=0.056 n=5+5)
FmtManyArgs              1.37µs ± 1%    1.36µs ± 1%    ~     (p=0.730 n=5+5)
GobDecode                14.6ms ± 4%    14.4ms ± 4%    ~     (p=0.690 n=5+5)
GobEncode                11.8ms ±20%    11.6ms ±15%    ~     (p=1.000 n=5+5)
Gzip                      507ms ± 0%     491ms ± 0%  -3.22%  (p=0.008 n=5+5)
Gunzip                   73.8ms ± 0%    73.9ms ± 0%    ~     (p=0.690 n=5+5)
HTTPClientServer          116µs ± 0%     116µs ± 0%    ~     (p=0.686 n=4+4)
JSONEncode               21.8ms ± 1%    21.6ms ± 2%    ~     (p=0.151 n=5+5)
JSONDecode                104ms ± 1%     103ms ± 1%  -1.08%  (p=0.016 n=5+5)
Mandelbrot200            9.53ms ± 0%    9.53ms ± 0%    ~     (p=0.421 n=5+5)
GoParse                  7.55ms ± 1%    7.51ms ± 1%    ~     (p=0.151 n=5+5)
RegexpMatchEasy0_32       158ns ± 0%     158ns ± 0%    ~     (all equal)
RegexpMatchEasy0_1K       606ns ± 1%     608ns ± 3%    ~     (p=0.937 n=5+5)
RegexpMatchEasy1_32       143ns ± 0%     144ns ± 1%    ~     (p=0.095 n=5+4)
RegexpMatchEasy1_1K       927ns ± 2%     944ns ± 2%    ~     (p=0.056 n=5+5)
RegexpMatchMedium_32     16.0ns ± 0%    16.0ns ± 0%    ~     (all equal)
RegexpMatchMedium_1K     69.3µs ± 2%    69.7µs ± 0%    ~     (p=0.690 n=5+5)
RegexpMatchHard_32       3.73µs ± 0%    3.73µs ± 1%    ~     (p=0.984 n=5+5)
RegexpMatchHard_1K        111µs ± 1%     110µs ± 0%    ~     (p=0.151 n=5+5)
Revcomp                   1.91s ±47%     1.77s ±68%    ~     (p=1.000 n=5+5)
Template                  138ms ± 1%     138ms ± 1%    ~     (p=1.000 n=5+5)
TimeParse                 787ns ± 2%     785ns ± 1%    ~     (p=0.540 n=5+5)
TimeFormat                729ns ± 1%     726ns ± 1%    ~     (p=0.151 n=5+5)

Updates #38740
Change-Id: I06c604874acdc1e63e66452dadee5df053045222
Reviewed-on: https://go-review.googlesource.com/c/go/+/233097
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
2020-05-29 15:39:54 +00:00
Josh Bleecher Snyder
364a05e2fe cmd/compile: add test for issue 37246
CL 233857 fixed the underlying issue for #37246,
which had arisen again as #38916.

Add the test case from #37246 to ensure it stays fixed.

Fixes #37246

Change-Id: If7fd75a096d2ce4364dc15509253c3882838161d
Reviewed-on: https://go-review.googlesource.com/c/go/+/233941
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
2020-05-14 15:18:29 +00:00
Michael Munday
f073395b73 cmd/compile: fix tuple selector bug in CSE pass
When tuple generators and selectors are eliminated as part of the
CSE pass we may end up with tuple selectors that are in different
blocks to the tuple generators that they correspond to. This breaks
the invariant that tuple generators and their corresponding
selectors must be in the same block. Therefore after CSE this
situation must be corrected.

Unfortunately the fixup code did not take into account that selectors
could be eliminated by CSE. It assumed that only the tuple generators
could be eliminated. In some situations this meant that it got into
a state where it was replacing references to selectors with references
to dead selectors in the wrong block.

To fix this we move the fixup code after the CSE rewrites have been
applied. This removes any difficult-to-reason-about interactions
with the CSE rewriter.

Fixes #38916.

Change-Id: I2211982dcdba399d03299f0a819945b3eb93b291
Reviewed-on: https://go-review.googlesource.com/c/go/+/233857
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-05-14 08:07:52 +00:00
Keith Randall
2cb10d42b7 cmd/compile: in prove, zero right shifts of positive int by #bits - 1
Taking over Zach's CL 212277. Just cleaned up and added a test.

For a positive, signed integer, an arithmetic right shift of count
(bit-width - 1) equals zero. e.g. int64(22) >> 63 -> 0. This CL makes
prove replace these right shifts with a zero-valued constant.

These shifts may arise in source code explicitly, but can also be
created by the generic rewrite of signed division by a power of 2.
// Signed divide by power of 2.
// n / c =       n >> log(c) if n >= 0
//       = (n+c-1) >> log(c) if n < 0
// We conditionally add c-1 by adding n>>63>>(64-log(c))
	(first shift signed, second shift unsigned).
(Div64 <t> n (Const64 [c])) && isPowerOfTwo(c) ->
  (Rsh64x64
    (Add64 <t> n (Rsh64Ux64 <t>
    	(Rsh64x64 <t> n (Const64 <typ.UInt64> [63]))
	(Const64 <typ.UInt64> [64-log2(c)])))
    (Const64 <typ.UInt64> [log2(c)]))

If n is known to be positive, this rewrite includes an extra Add and 2
extra Rsh. This CL will allow prove to replace one of the extra Rsh with
a 0. That replacement then allows lateopt to remove all the unneccesary
fixups from the generic rewrite.

There is a rewrite rule to handle this case directly:
(Div64 n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) ->
	(Rsh64Ux64 n (Const64 <typ.UInt64> [log2(c)]))
But this implementation of isNonNegative really only handles constants
and a few special operations like len/cap. The division could be
handled if the factsTable version of isNonNegative were available.
Unfortunately, the first opt pass happens before prove even has a
chance to deduce the numerator is non-negative, so the generic rewrite
has already fired and created the extra Ops discussed above.

Fixes #36159

By Printf count, this zeroes 137 right shifts when building std and cmd.

Change-Id: Iab486910ac9d7cfb86ace2835456002732b384a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/232857
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2020-05-11 16:23:52 +00:00
Emmanuel T Odeke
7cbee12444 cmd/compile: improve error when setting unexported fields
Improve the error user experience when users try to set/refer
to unexported fields and methods of struct literals, by directly saying

    "cannot refer to unexported field or method"

Fixes #31053

Change-Id: I6fd3caf64b7ca9f9d8ea60b7756875e340792d59
Reviewed-on: https://go-review.googlesource.com/c/go/+/201657
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-05-08 20:44:01 +00:00
Emmanuel T Odeke
26de581a70 cmd/compile: omit file:pos for non-existent errors
Omits printing the file:line:column when trying to
open non-existent files

Given:
    go tool compile x.go

* Before:
    x.go:0: open x.go: no such file or directory

* After:
    open x.go: no such file or directory

Reverts the revert in CL 231043 by only fixing the case
of non-existent errors which is what the original bug
was about. The fix for "permission errors" will come later
on when I have bandwidth to investigate the differences
between running with root and why os.Open works for some
builders and not others.

Fixes #36437

Change-Id: I9c8a0981ad708b504bb43990a4105b42266fa41f
Reviewed-on: https://go-review.googlesource.com/c/go/+/230941
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2020-05-08 20:28:57 +00:00
Martin Möhrmann
6ed4661807 cmd/compile: optimize make+copy pattern to avoid memclr
match:
 m = make([]T, x); copy(m, s)
for pointer free T and x==len(s) rewrite to:
 m = mallocgc(x*elemsize(T), nil, false); memmove(&m, &s, x*elemsize(T))
otherwise rewrite to:
 m = makeslicecopy([]T, x, s)

This avoids memclear and shading of pointers in the newly created slice
before the copy.

With this CL "s" is only be allowed to bev a variable and not a more
complex expression. This restriction could be lifted in future versions
of this optimization when it can be proven that "s" is not referencing "m".

Triggers 450 times during make.bash..
Reduces go binary size by ~8 kbyte.

name                           old time/op  new time/op  delta
MakeSliceCopy/mallocmove/Byte  71.1ns ± 1%  65.8ns ± 0%  -7.49%  (p=0.000 n=10+9)
MakeSliceCopy/mallocmove/Int   71.2ns ± 1%  66.0ns ± 0%  -7.27%  (p=0.000 n=10+8)
MakeSliceCopy/mallocmove/Ptr    104ns ± 4%    99ns ± 1%  -5.13%  (p=0.000 n=10+10)
MakeSliceCopy/makecopy/Byte    70.3ns ± 0%  68.0ns ± 0%  -3.22%  (p=0.000 n=10+9)
MakeSliceCopy/makecopy/Int     70.3ns ± 0%  68.5ns ± 1%  -2.59%  (p=0.000 n=9+10)
MakeSliceCopy/makecopy/Ptr      102ns ± 0%    99ns ± 1%  -2.97%  (p=0.000 n=9+9)
MakeSliceCopy/nilappend/Byte   75.4ns ± 0%  74.9ns ± 2%  -0.63%  (p=0.015 n=9+9)
MakeSliceCopy/nilappend/Int    75.6ns ± 0%  76.4ns ± 3%    ~     (p=0.245 n=9+10)
MakeSliceCopy/nilappend/Ptr     107ns ± 0%   108ns ± 1%  +0.93%  (p=0.005 n=9+10)

Fixes #26252

Change-Id: Iec553dd1fef6ded16197216a472351c8799a8e71
Reviewed-on: https://go-review.googlesource.com/c/go/+/146719
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-05-07 17:50:24 +00:00
Cuong Manh Le
0f47c12a29 cmd/compile: do not emit code for discardable blank fields
Fixes #38690

Change-Id: I3544daf617fddc0f89636265c113001178d16b0c
Reviewed-on: https://go-review.googlesource.com/c/go/+/230121
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2020-05-06 04:34:54 +00:00
Keith Randall
b4ecafc986 cmd/compile: restrict bit test rewrite rules
The {AND,OR,XOR}const ops can only take an int32 as an argument.
Make sure that when rewriting a BTx op to one of these, the result
has no high-order bits.

Fixes #38746

Change-Id: Ia7c5f76952329f60974bc033c29a5433610f3b28
Reviewed-on: https://go-review.googlesource.com/c/go/+/231977
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2020-05-05 15:41:37 +00:00
Keith Randall
9ed0fb42e3 cmd/compile: add indexed memory modification ops to amd64
name            old time/op  new time/op  delta
Modify-16        404ns ± 1%   365ns ± 1%  -9.73%  (p=0.000 n=10+10)
ConstModify-16   407ns ± 0%   385ns ± 2%  -5.56%  (p=0.000 n=9+10)

Seems to generally help generated code.

Binary size change is in the noise.

Change-Id: I57891bfaf0f7dfc5d143bb9f7ebafc7079d2614f
Reviewed-on: https://go-review.googlesource.com/c/go/+/228098
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2020-04-30 17:21:31 +00:00
Keith Randall
882ec701d2 cmd/compile: add indexed load+op operations to amd64
name        old time/op  new time/op  delta
LoadAdd-16   545ns ± 0%   456ns ± 0%  -16.31%  (p=0.000 n=10+10)

Update #36468

Change-Id: I84f390d55490648fa1f58cdbc24fd74c4f1bc8c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/227960
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2020-04-30 17:19:57 +00:00
Austin Clements
eda6fe3572 Revert "cmd/compile: omit file:pos for non-existent, permission errors"
This reverts commit 4f7053c87f.

Reason for revert: Newly added test is failing on several builders.

Change-Id: I22dcbfebf2f57735b2f479886bbeb623f95b132f
Reviewed-on: https://go-review.googlesource.com/c/go/+/231043
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-04-30 02:29:55 +00:00
Emmanuel T Odeke
4f7053c87f cmd/compile: omit file:pos for non-existent, permission errors
Omits printing the file:line:column when trying to open either
* non-existent files
* files without permission

Given:
    go tool compile x.go

For either of x.go not existing, or if no read permissions:

* Before:
    x.go:0: open x.go: no such file or directory
    x.go:0: open x.go: permission denied

* After:
    open x.go: no such file or directory
    open x.go: permission denied

While here, noticed an oddity with the Linux builders, that appear
to always be running under root, hence the test for permission errors
with 0222 -W-*-W-*-W- can't pass on linux-amd64 builders.
The filed bug is #38608.

Fixes #36437

Change-Id: I9645ef73177c286c99547e3a0f3719fa07b35cb5
Reviewed-on: https://go-review.googlesource.com/c/go/+/229357
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2020-04-30 01:17:47 +00:00