This change adds line position tests for several yyerror calls in the
typechecker that are currently not tested in any way.

Untested yyerror calls were found by replacing them with

  yerrorl(src.NoXPos, ...)

(thus destroying position information in the error), and then running
the test suite. No failures means no test coverage for the relevant
yyerror call.

For #19683

Change-Id: Iedb3d2f02141b332e9bfa76dbf5ae930ad2fddc3
Reviewed-on: https://go-review.googlesource.com/41477
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

doubleselect.go defines a flag to control the number of iterations,
but never called flag.Parse so it was unusable.

Change-Id: Ib5d0c7119e7f7c9a808dcc02d0d9cc6ba5bbc16e
Reviewed-on: https://go-review.googlesource.com/41299Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

While we're here, do minor style cleanup.
Also, since we know exactly how many init
functions there are, use that knowledge.

This is cleanup prior to a more substantive CL.

Change-Id: I2bba60b3c051c852590f798f45e8268f8bc54ca8
Reviewed-on: https://go-review.googlesource.com/41499
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It is mildly wasteful to always create values
that must sometimes then be dead code eliminated.
Given that it is very easy to avoid, do so.

Noticed when examining a package with thousands
of generated wrappers, each of which uses
only a handful of Values to compile.

Change-Id: If02eb4aa786dfa20f7aa43e8d729dad8b3db2786
Reviewed-on: https://go-review.googlesource.com/41502
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

dumptypestructs did several different jobs.
Split them into separate functions
and call them in turn.

Hand dumptypestructs a list of dcls,
rather than reading the global.

Rename dumpptabs for (marginal) clarity.

This is groundwork for compiling autogenerated
functions concurrently.

Passes toolstash-check.

Change-Id: I627a1dffc70a7e4b7b4436ab19af1406267f01dc
Reviewed-on: https://go-review.googlesource.com/41501
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Follow-up to codereview feedback on CL 41409.

Passes toolstash-check.

Change-Id: Ica6658bdb8215fc4a0a30f41fe7bc8d9a8b109b4
Reviewed-on: https://go-review.googlesource.com/41412
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: If5631eae7e2ad2bef56e79b82f77105246e68773
Reviewed-on: https://go-review.googlesource.com/41494
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It was just a cache, and the CL series yesterday
removed 40% of the calls to types.Linksym in make.bash.

Testing atop CL 40693 (backend concurrency)
indicates that removing it is actually a very minor
performance improvement.

Passes toolstash-check.

Change-Id: I97c2973036964acdd11b3cb842bc31f33ae60389
Reviewed-on: https://go-review.googlesource.com/41492
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This commit fixes an issue reported by golint.  The code was modified by running

gorename -from '"encoding/base64".rawUrlRef' -to rawURLRef

Change-Id: I428167e0808e85b2dc6b516298ff5c090dfe3430
Reviewed-on: https://go-review.googlesource.com/41474Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Also, replace "PtrSize == 4 && Arch != amd64p32" with "RegSize == 4".

Passes toolstash-check -all.

Updates #19954.

Change-Id: I79b2ee9324f4fa53e34c9271d837ea288b5d7829
Reviewed-on: https://go-review.googlesource.com/41491
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Passes toolstash-check -all.

Updates #19954.

Change-Id: Ic162306eed105912491bf1df47e32c32653f824c
Reviewed-on: https://go-review.googlesource.com/41490
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The last mention of those types in this package are in:

  commit 6bd0d054
  Author: Russ Cox <rsc@golang.org>
  Date:   Thu Nov 6 19:56:55 2014 -0500

      cmd/objdump, cmd/pprof: factor disassembly into cmd/internal/objfile

Found with honnef.co/go/tools/cmd/unused.

Change-Id: Iacc2902f7d0784ac0efdd92da239f3e97491469a
Reviewed-on: https://go-review.googlesource.com/41472Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Use PtrSize and Widthptr instead. CL prepared mostly with sed and
uniq.

Passes toolstash-check -all.

Fixes #19954.

Change-Id: I09371bd7128672885cb8bc4e7f534ad56a88d755
Reviewed-on: https://go-review.googlesource.com/40506
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

TestSeekError has been added in CL 41311. This
test doesn't build on Plan 9 because syscall.ESPIPE
is not defined on Plan 9.

This change defines syscall.ESPIPE on Plan 9.

Fixes #20078.

Change-Id: I3d9e95b00e0c4e43312eada6441d80961ae6bd67
Reviewed-on: https://go-review.googlesource.com/41471
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

This functionality can be implemented in package types without a
trampoline back to gc.

Change-Id: Iaff7169fece35482e654553bf16b07dc67d1991a
Reviewed-on: https://go-review.googlesource.com/41416
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I2d287981d5fcef3aace948c405d618f46200948e
Reviewed-on: https://go-review.googlesource.com/41450
Run-TryBot: Todd Neal <todd@tneal.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Current implementation use EPIPE as an error for Seek on pipes.
According to http://pubs.opengroup.org/onlinepubs/009695399/functions/lseek.html,
it should use ESPIPE instead.

Fixes #20066

Change-Id: I24c3b95be946bc19a287d6b10f447b034a9a1283
Reviewed-on: https://go-review.googlesource.com/41311Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I9d399db8ac26ad44adeace3bf1e5b11cbfe3e0d3
Reviewed-on: https://go-review.googlesource.com/41313Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Hopefully the last refactoring of TestRespectGroupSticky:
* Properly tested (+simplified) FreeBSD fix
* Tested on Darwin (10.12.4)
* Rename to TestRespectSetgidDir (I believe this is the accepted
  terminology)

Fixes golang/go#19596.

Change-Id: I8d689ac3e245846cb3f1338ea13e35be512ccb9c
Reviewed-on: https://go-review.googlesource.com/41430Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>

Passes toolstash-check.

Change-Id: I0cb2ea9ca7ec2449999af28457270ff7b3324e92
Reviewed-on: https://go-review.googlesource.com/41410
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I4a5c841eb16e05db7d923d4c3c7cd2d7695fa4af
Reviewed-on: https://go-review.googlesource.com/41409
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I1a5809f15c84f9d26064a567b45468fa56e6d5e9
Reviewed-on: https://go-review.googlesource.com/41408
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I9940909949da58e780696e6de0c21f95be7a8816
Reviewed-on: https://go-review.googlesource.com/41407
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: Ic235960e85b8faeffe81dac2334c09757578a552
Reviewed-on: https://go-review.googlesource.com/41406
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I00a8200370d56772f604a099654f9d838c4f62e2
Reviewed-on: https://go-review.googlesource.com/41405
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Change a few functions so that instead of
accepting a *types.Sym and calling Linksym
themselves, they accept an *obj.LSym.
Adapt the callsites.

Passes toolstash-check.

Change-Id: Ic5d3f306f2fdd3913281215a1f54d893a966bb1f
Reviewed-on: https://go-review.googlesource.com/41404
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I5309125e0da65a5f240e53472b1c911252f0a472
Reviewed-on: https://go-review.googlesource.com/41403
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I0cc4fe608a50681845a92053cb3888ea127b521a
Reviewed-on: https://go-review.googlesource.com/41402
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Automated refactoring using gorename, eg, and gofmt -r.

Passes toolstash-check.

Change-Id: Ib50f368bf62a07e5ced50b1b92a29c669ba9a158
Reviewed-on: https://go-review.googlesource.com/41401
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Passes toolstash-check.

Change-Id: I9398dd0fd9112d907f838ea911a7724dda5bbaee
Reviewed-on: https://go-review.googlesource.com/41400
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

This batch from reflect.go.
Changes made manually, since they are simple,
few, and typechecked by the compiler.

Passes toolstash-check.

Change-Id: I0030daab2dac8e7c95158678c0f7141fd90441f9
Reviewed-on: https://go-review.googlesource.com/41399
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

The only remaining uses of duintxx
are in the implementation of duintNN.
I hope to inline those once I figure out why
CL 40864 is broken.

Note that some uses of duintxx with width Widthint
were converted into duintptr.
I did that, since #19954 is officially going to move forward.

Passes toolstash-check.

Change-Id: Id25253b711ea589d0199b51be9a3c18ca1af59ce
Reviewed-on: https://go-review.googlesource.com/41398
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Follow-up to previous CL.

gorename -from '"cmd/compile/internal/gc".duintxxLSym' -to duintxx
gorename -from '"cmd/compile/internal/gc".duint8LSym' -to duint8
gorename -from '"cmd/compile/internal/gc".duint16LSym' -to duint16
gorename -from '"cmd/compile/internal/gc".duint32LSym' -to duint32
gorename -from '"cmd/compile/internal/gc".duintptrLSym' -to duintptr
gorename -from '"cmd/compile/internal/gc".dbvecLSym' -to dbvec
gorename -from '"cmd/compile/internal/gc".dsnameLSym' -to dsname
gorename -from '"cmd/compile/internal/gc".dsymptrLSym' -to dsymptr
gorename -from '"cmd/compile/internal/gc".dsymptrOffLSym' -to dsymptrOff
gorename -from '"cmd/compile/internal/gc".dsymptrWeakOffLSym' -to dsymptrWeakOff

Passes toolstash-check.

Change-Id: I007f57340f9e8b1468553242556ae25a71167e8c
Reviewed-on: https://go-review.googlesource.com/41397
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

This is an automated refactoring to eliminate
all dxxx calls in gc/obj.go that accept types.Sym
instead of obj.LSym parameters.

The refactoring was of the form:

gorename -from '"cmd/compile/internal/gc".duintxx' -to Duintxx
gorename -from '"cmd/compile/internal/gc".duintxxLSym' -to DuintxxLSym
eg -t t.go -w cmd/compile/internal/gc
gofmt -r 'DuintxxLSym -> duintxxLSym' -w cmd/compile/internal/gc

where t.go looked like:

func before(s *types.Sym, off int, v uint64, wid int) int {
	return gc.Duintxx(s, off, v, wid)
}

func after(s *types.Sym, off int, v uint64, wid int) int {
	return gc.DuintxxLSym(s.Linksym(), off, v, wid)
}

The rename/gofmt shenanigans were to work around
limitations and bugs in eg and gorename.

The resulting code in reflect.go looks temporarily ugly,
but it makes refactoring and cleanup opportunities
much clearer.

Next step is to rename all the dxxx methods to rename the -LSym suffix
and clean up reflect.go.

The renaming is left for a separate CL to make the changes in
this CL more obvious, and thus hopefully easier to review.

Passes toolstash-check.

Change-Id: Ib31a2b6fd146ed03a855d20ecb0433f0f74e2f10
Reviewed-on: https://go-review.googlesource.com/41396
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

- Add new BranchStmt.Target field: It's the destination for break,
  continue, or goto statements.

- When parsing with CheckBranches enabled, set the BranchStmt.Target
  field. We get the information practically for free from the branch
  checker, so keep it for further use.

- Fix a couple of comments.

- This could use a test, but the new Target field is currently not
  used, and writing a test is tedious w/o a general tree visitor.
  Do it later. For now, visually verified output from syntax dump.

Change-Id: Id691d89efab514ad885e19ac9759506106579520
Reviewed-on: https://go-review.googlesource.com/40988Reviewed-by: Matthew Dempsky <mdempsky@google.com>

ARM's udiv function is nosplit and it shouldn't be preemptied
(passing args in registers). It is in some sense like DUFFCOPY,
which we don't mark as safepoint.

Change-Id: I49f7c4e69e787ac364d0b0def0661e79a0ea9e69
Reviewed-on: https://go-review.googlesource.com/41370
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

This doesn't appear to be present on Windows Server 2012 or 2016:

https://build.golang.org/log/6ea21b99c9b8a2be20f9aeaec6c425b84faf1af7
https://build.golang.org/log/2bcf04f1df003577352f4f987a39a59a081094ee

Updates golang/go#17513
Updates golang/go#20073

Change-Id: I72820704b4cb16bb1720b7f6a9f2e10028c71334
Reviewed-on: https://go-review.googlesource.com/41395Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

Currently one needs to refer to the sources to have a list of accepted
debug keys. We can copy what 'ssa/help' does and introspect the list of
debug keys to print a more detailed help:

    $ go tool compile -d help
    usage: -d arg[,arg]* and arg is <key>[=<value>]

    <key> is one of:

    	append    	print information about append compilation
    	closure   	print information about closure compilation
    	disablenil	disable nil checks
    	dclstack  	run internal dclstack check
    	gcprog    	print dump of GC programs
    	nil       	print information about nil checks
    	panic     	do not hide any compiler panic
    	slice     	print information about slice compilation
    	typeassert	print information about type assertion inlining
    	wb        	print information about write barriers
    	export    	print export data
    	pctab     	print named pc-value table
    	ssa/help  	print help about SSA debugging

    <value> is key-specific.

    Key "pctab" supports values:
    	"pctospadj", "pctofile", "pctoline", "pctoinline", "pctopcdata"

For '-d help' to be discoverable, a hint is given in the -d flag
description.

A last thing, today at least one go file needs to be provided to get to
the code printing ssa/help.

  $ go tool compile -d ssa/help foo.go

Add a check so one can just do '-d help' or '-d ssa/help'

Caught by trybot: I needed to update fmt_test.go as I'm introducing the
usage of %-*s in a format string.

Fixes #20041

Change-Id: Ib2858b038c1bcbe644aa3b1a371009710c6d957d
Reviewed-on: https://go-review.googlesource.com/41091
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

The experiment "clobberdead" clobbers all pointer fields that the
compiler thinks are dead, just before and after every safepoint.
Useful for debugging the generation of live pointer bitmaps.

Helped find the following issues:
Update #15936
Update #16026
Update #16095
Update #18860

Change-Id: Id1d12f86845e3d93bae903d968b1eac61fc461f9
Reviewed-on: https://go-review.googlesource.com/23924
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

Currently TestSetGCPercent checks that NextGC is within 10 MB of the
expected value. For some reason it's much noisier on some of the
builders. To get these passing again, raise the threshold to 20 MB.

Change-Id: I14e64025660d782d81ff0421c1eb898f416e11fe
Reviewed-on: https://go-review.googlesource.com/41374
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>