Normally 64-bit div/mod is turned into runtime calls on 32-bit
arch, but the front end leaves power-of-two constant division
and hopes the SSA backend turns into a shift or AND. The SSA rule is

(Mod64u <t> n (Const64 [c])) && isPowerOfTwo(c) -> (And64 n (Const64 <t> [c-1]))

But isPowerOfTwo returns true only for positive int64, which leaves
out 1<<63 unhandled. Add a special case for 1<<63.

Fixes #21517.

Change-Id: I02d27dc7177d4af0ee8d7f5533714edecddf8c95
Reviewed-on: https://go-review.googlesource.com/56890Reviewed-by: Keith Randall <khr@golang.org>

I'm writing a matching implementation of the time package and missed
the "add one day in a leap year" block. This test would have caught my
error.

I understand we can't add test cases for every Date but it seems like
"tripped up someone attempting to reimplement this" is a good
indicator it may trip up people in the future.

Change-Id: I4c3b51e52e269215ec0e52199afe604482326edb
Reviewed-on: https://go-review.googlesource.com/56490Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Matt Layher <mdlayher@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #21486.

Change-Id: I01794f008404f0e2d8a1408309ae6055513c5b49
Reviewed-on: https://go-review.googlesource.com/57030
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Instructions added in https://golang.org/cl/18853

2nd change out of 3 to cover AMD64 SSSE3 instruction set in Go asm.
This commit does not actually add any new instructions, only
enables some test cases.

Change-Id: I9596435b31ee4c19460a51dd6cea4530aac9d198
Reviewed-on: https://go-review.googlesource.com/56835
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>

Will debug soon but wanted to fix builders.

Change-Id: I921d58d1272370f3102ba1f86ad535f4c0f6b8db
Reviewed-on: https://go-review.googlesource.com/56970
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

After the key and value arrays, we have an overflow pointer.
So there's no way a past-the-end key or value pointer could point
past the end of the containing bucket.

So we don't need this additional protection.

Update #21459

Change-Id: I7726140033b06b187f7a7d566b3af8cdcaeab0b0
Reviewed-on: https://go-review.googlesource.com/56772
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Avelino <t@avelino.xxx>

Package.Internal.Imports is enough in nearly all cases,
and not maintaining a separate Package.Internal.Deps
avoids the two lists ending up out of sync.
(In some synthesized packages created during go test,
only Internal.Imports is initialized.)

Change-Id: I83f6a3ec6e6cbd75382f1fa0e439d31feec32d5a
Reviewed-on: https://go-review.googlesource.com/56278Reviewed-by: Ian Lance Taylor <iant@golang.org>

Before it was obj, but if you don't have everything paged in
that sounds a bit like an object file. Use objdir, which is more
clearly a directory and also matches the Action.Objdir struct field.

Change-Id: I268042800f9ca05721814d7f18c728acb4831232
Reviewed-on: https://go-review.googlesource.com/56277Reviewed-by: Ian Lance Taylor <iant@golang.org>

Update BinaryOnly test by adding import _ "fmt".

Change-Id: I3a1dcfb83a27d8ff50a658060a46e1a3f481f6c7
Reviewed-on: https://go-review.googlesource.com/56276Reviewed-by: Ian Lance Taylor <iant@golang.org>

ImportPaths is also the name of a top-level function.
It is confusing to have a capitalized local variable.

Change-Id: I1313e05ade4934d4ee250a67e5af6d1bd6229aca
Reviewed-on: https://go-review.googlesource.com/56275
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Now that we have t.Helper, might as well use it to make the
reported failure lines more helpful.

Change-Id: I2a0c64e9ca7bdc0eaf2b62f9f855c41467767084
Reviewed-on: https://go-review.googlesource.com/56274
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

When we make the go command pay attention to content
instead of time, we want this test to continue working.

Change-Id: Ib7d9d0d62bfe87810d71bdfc4f29561a8c70eccc
Reviewed-on: https://go-review.googlesource.com/56273
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Using a fake CC fails today if runtime/cgo is stale, because the
build will try to rebuild runtime/cgo using the fake CC, and the
fake CC is not a working C compiler.

Worse, in the future, when the go command is sensitive to details like
the fact that different CCs produce different outputs, putting in
the fake CC will make runtime/cgo look stale even if it was
formerly up-to-date.

Fix both problems by not overriding CC and instead looking at
the command being run to make sure the flags are quoted as expected.

Change-Id: I4417e35cfab33a07546cc90748ddb6119d8fdb2d
Reviewed-on: https://go-review.googlesource.com/56272
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This makes the construction of pmain.Internal.Imports consistently ordered.

Change-Id: I82348a18c7824378aa7e5bc5b6bcd550d4b758da
Reviewed-on: https://go-review.googlesource.com/56271
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

There are two changes in this CL.

1. Add new forms of MOVH/MOVHS/MOVHU.
   MOVHS R0<<0(R1), R2   // ldrsh
   MOVH  R0<<0(R1), R2   // ldrsh
   MOVHU R0<<0(R1), R2   // ldrh
   MOVHS R2, R5<<0(R1)   // strh
   MOVH  R2, R5<<0(R1)   // strh
   MOVHU R2, R5<<0(R1)   // strh

2. Simpify "MVN $0xffffffaa, Rn" to "MOVW $0x55, Rn".
   It is originally assembled to two instructions.
   "MOVW offset(PC), R11"
   "MVN R11, Rn"

Change-Id: I8e863dcfb2bd8f21a04c5d627fa7beec0afe65fb
Reviewed-on: https://go-review.googlesource.com/53690
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Fixes #21518

Change-Id: Idd67e3f0410d0ce991b34dcc0c8f15e0d5c529c9
Reviewed-on: https://go-review.googlesource.com/56850Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This commit defines the inverse of error function (erfinv) in the
math package. The function is based on the rational approximation
of percentage points of normal distribution available at
https://www.jstor.org/stable/pdf/2347330.pdf.

Fixes #6359

Change-Id: Icfe4508f623e0574c7fffdbf7aa929540fd4c944
Reviewed-on: https://go-review.googlesource.com/46990
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

Updates #13745

Recognize z.Mul(x, x) as squaring for Floats and use
the internal z.sqr(x) method for nat on the mantissa.

Change-Id: I0f792157bad93a13cae1aecc4c10bd20c6397693
Reviewed-on: https://go-review.googlesource.com/56774Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

updates #13745

A squared rational is always positive and can not
be reduced since the numerator and denominator had
no previous common factors.  The nat multiplication
can be performed using the internal sqr method.

Change-Id: I558f5b38e379bfd26ff163c9489006d7e5a9cfaa
Reviewed-on: https://go-review.googlesource.com/56776Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I1929ea7e4ed88631ef729472ffe474016efec3e8
Reviewed-on: https://go-review.googlesource.com/56370Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Found with mvdan.cc/unindent. Prioritized the ones with the biggest wins
for now.

Change-Id: I2b032e45cdd559fc9ed5b1ee4c4de42c4c92e07b
Reviewed-on: https://go-review.googlesource.com/56470
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Another attempt to fix build

Change-Id: I26137c115ad4b5f5a69801ed981c146adf6e824c
Reviewed-on: https://go-review.googlesource.com/56750Reviewed-by: Ian Lance Taylor <iant@golang.org>

Hopefully fixes build.

Change-Id: If0629b95b923a65e4507073cf7aa44a5e178fc0f
Reviewed-on: https://go-review.googlesource.com/56711Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>

Change-Id: Id717054cb3c4537452f8ff848445b0c20196a373
Reviewed-on: https://go-review.googlesource.com/33579
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

Updates #21487

Change-Id: Ia549a87a8a305cc80da11ea9bd904402f1a14689
Reviewed-on: https://go-review.googlesource.com/56321Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I7f7b1e7ef832d53a93562b08ae914d023247c2c0
Reviewed-on: https://go-review.googlesource.com/56312
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Just to get rid of lots of .Name() stutter in printf calls.

Change-Id: I86cf00b3f7b2172387a1c6a7f189c1897fab6300
Reviewed-on: https://go-review.googlesource.com/56630
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Use mallogc instead of newarray to save some overhead since
makechan already checks for _MaxMem constraints.

Flattens the if else construct that determines if buf and hchan struct
should be allocated in one mallocgc call and where buf should point to.

Uses maxSliceCap to avoid divisions similar to makeslice.

name                old time/op  new time/op  delta
MakeChan/Byte       82.0ns ± 8%  81.4ns ± 7%    ~     (p=0.643 n=10+10)
MakeChan/Int        97.9ns ± 2%  96.6ns ± 2%  -1.40%  (p=0.009 n=10+10)
MakeChan/Ptr         128ns ± 3%   120ns ± 1%  -6.63%  (p=0.000 n=10+10)
MakeChan/Struct/0   66.7ns ± 4%  66.4ns ± 2%    ~     (p=0.697 n=10+10)
MakeChan/Struct/32   136ns ± 1%   130ns ± 0%  -4.42%  (p=0.000 n=10+10)
MakeChan/Struct/40   150ns ± 1%   150ns ± 1%    ~     (p=0.725 n=10+10)

Change-Id: Ibb5675d0843a072aae2bfa58ecd39cf4cd926533
Reviewed-on: https://go-review.googlesource.com/55132
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Stack allocated hmap structs are explicitly zeroed before being
passed by pointer to makemap.

Heap allocated hmap structs are created with newobject
which also zeroes on allocation.

Therefore, setting the hmap fields to 0 or nil is redundant
since they will have been zeroed when hmap was allocated.

Change-Id: I5fc55b75e9dc5ba69f5e3588d6c746f53b45ba66
Reviewed-on: https://go-review.googlesource.com/56291Reviewed-by: Keith Randall <khr@golang.org>

Fix a missed change from:

https://golang.org/cl/56190

pointed out on the fossil mailing list shortly after submission
of the change mentioned above.  See:

http://www.mail-archive.com/fossil-users@lists.fossil-scm.org/msg25736.html

This change adds fossil to the general regular expression that is checked last
in the import path check.

For #10010

Change-Id: I6b711cdb1a8d4d767f61e1e28dc29dce529e0fad
Reviewed-on: https://go-review.googlesource.com/56491Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>

We're making two extra round-trips to C to malloc and free strings
that originate in Go and don't escape. Skip those round-trips by
allocating null-terminated slices in Go memory instead.

Change-Id: I9e4c5ad999a7924ba50b82293c52073ec75518be
Reviewed-on: https://go-review.googlesource.com/56530
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Updates #21253

Change-Id: Iece71a27207b578618cafb378dac2362517363d0
Reviewed-on: https://go-review.googlesource.com/52531
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We already combine const stores up-to MOVQstoreconst.
Combine 2 64-bit stores of const zero into 1 sse store of 128-bit zero.

Shaves significant (>1%) amount of code from go tool:
/localdisk/itocar/golang/bin/go 10334877
go_old 10388125 [53248 bytes]

global text (code) = 51041 bytes (1.343944%)
read-only data = 663 bytes (0.039617%)
Total difference 51704 bytes (0.873981%)

Change-Id: I7bc40968023c3a69f379b10fbb433cdb11364f1b
Reviewed-on: https://go-review.googlesource.com/56250
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>

Instructions are implemented in the following revisions:
PCMPESTRI - https://golang.org/cl/22337
PHMINPOSUW - https://golang.org/cl/18853

It is unknown when x86test will be updated/re-run, but tests are useful
to check which x86 instructions are not yet supported.
As an example of tool that uses this information, there is Damien
Lespiau x86db.

Part of the mission to add missing amd64 SSE4 instructions to Go asm.

Change-Id: I512ff26040f47a0976b3e37000fb1f37eac5b762
Reviewed-on: https://go-review.googlesource.com/55830
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>

This makes it much easier to run individual failing subtests.

Use $(go env CC) instead of always defaulting to clang; this makes it
easier to test with other compilers.

Run C binaries to detect incompatible compiler/kernel pairings instead
of sniffing versions.

updates #21196

Change-Id: I0debb3cc4a4244df44b825157ffdc97b5c09338d
Reviewed-on: https://go-review.googlesource.com/52910
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

The existing implementation is translated from C, which uses a
polynomial coefficient very close to 1/6. If the function uses
1/6 as this coeffient, the result of Exp(1) will be more accurate.
And this change doesn't introduce more error to Exp function.

Fixes #20319

Change-Id: I94c236a18cf95570ebb69f7fb99884b0d7cf5f6e
Reviewed-on: https://go-review.googlesource.com/49294Reviewed-by: Robert Griesemer <gri@golang.org>

Prioritized the chunks of code with 8 or more levels of indentation.
Basically early breaks/returns and joining nested ifs.

Change-Id: I6817df1303226acf2eb904a29f2db720e4f7427a
Reviewed-on: https://go-review.googlesource.com/55630
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Current code detect runtime/cgo iff the package or sub packages imports
runtime/cgo directly. However, when we are using linkshared, imported
shared libraries might have already included runtime/cgo.
This CL handles later case by looking an actual runtime/cgo symbol.

Change-Id: I35e7dfdb5e1a939eafc95a0259ee1af9782bc864
Reviewed-on: https://go-review.googlesource.com/56310Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

While LoadCmdDylib represents LC_LOAD_DYLIB,
LoadCmdDylinker represents LC_ID_DYLINKER.
This is confusing because there is another command called LC_LOAD_DYLINKER.
LC_ID_DYLINKER is not included in normal binary, it is only used for
/usr/lib/dyld as far as I know. So, perhaps this is a mistake.

Change-Id: I6ea61664a26998962742914af5688e094a233541
Reviewed-on: https://go-review.googlesource.com/56330Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

add tests for LC_LOAD_DYLIB.

Change-Id: Ic4b7a0f6296709175e9a75240aecd1d5291ade4b
Reviewed-on: https://go-review.googlesource.com/56311Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>