Ian Lance Taylor [Thu, 31 Mar 2016 20:58:33 +0000 (13:58 -0700)]
cmd/compile: s.f aliases itself
The change in 20907 fixed varexpr but broke aliased. After that change,
a reference to a field in a struct would not be seen as aliasing itself.
Before that change, it would, but only because all fields in a struct
aliased everything.
This CL changes the compiler to consider all references to a field as
aliasing all other fields in that struct. This is imperfect--a
reference to one field does not alias another field--but is a simple fix
for the immediate problem. A better fix would require tracking the
specific fields as well.
Fixes #15042.
Change-Id: I5c95c0dd7b0699e53022fce9bae2e8f50d6d1d04
Reviewed-on: https://go-review.googlesource.com/21390
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Brad Fitzpatrick [Thu, 31 Mar 2016 12:49:23 +0000 (05:49 -0700)]
net/http: update bundled http2
Updates x/net/http2 to git rev 31df19d6 for changes since Go 1.6.
The main change was https://go-review.googlesource.com/19726 (move
merging of HEADERS and CONTINUATION into Framer), but there were a few
garbage reduction changes too.
Christopher Nelson [Thu, 31 Mar 2016 20:22:54 +0000 (16:22 -0400)]
cmd/link: Replace fmt.Sprintf with filepath.Join
In a number of places the code was joining filepaths explicitly with
"/", instead of using filepath.Join. This may cause problems on Windows
(or other) platforms.
This is in support of https://go-review.googlesource.com/#/c/18057
Joe Tsai [Wed, 30 Mar 2016 05:04:03 +0000 (22:04 -0700)]
compress/flate: make Reader.Read return io.EOF eagerly
Rather than checking the block final bit on the next invocation
of nextBlock, we check it at the termination of the current block.
This ensures that we return (n, io.EOF) instead of (0, io.EOF)
more frequently for most streams.
However, there are certain situations where an eager io.EOF is not done:
1) We previously returned from Read because the write buffer of the internal
dictionary was full, and it just so happens that there is no more data
remaining in the stream.
2) There exists a [non-final, empty, raw block] after all blocks that
actually contain uncompressed data. We cannot return io.EOF eagerly here
since it would break flushing semantics.
Both situations happen infrequently, but it is still important to note that
this change does *not* guarantee that flate will *always* return (n, io.EOF).
Furthermore, this CL makes no changes to the pattern of ReadByte calls
to the underlying io.ByteReader.
Below is the motivation for this change, pulling the text from
@bradfitz's CL/21290:
net/http and other things work better when io.Reader implementations
return (n, io.EOF) at the end, instead of (n, nil) followed by (0,
io.EOF). Both are legal, but the standard library has been moving
towards n+io.EOF.
An investigation of net/http connection re-use in
https://github.com/google/go-github/pull/317 revealed that with gzip
compression + http/1.1 chunking, the net/http package was not
automatically reusing the underlying TCP connections when the final
EOF bytes were already read off the wire. The net/http package only
reuses the connection if the underlying Readers (many of them nested
in this case) all eagerly return io.EOF.
In addition to net/http, this behavior also helps things like
ioutil.ReadAll (see comments about performance improvements in
https://codereview.appspot.com/49570044)
Keith Randall [Mon, 28 Mar 2016 18:25:17 +0000 (11:25 -0700)]
cmd/compile: better job of naming compound types
Compound AUTO types weren't named previously. That was because live
variable analysis (plive.go) doesn't handle spilling to compound types.
It can't handle them because there is no valid place to put VARDEFs when
regalloc is spilling compound types.
Instead, we split named AUTOs into individual one-word variables. For
example, a string s gets split into a byte ptr s.ptr and an integer
s.len. Those two variables can be spilled to / restored from
independently. As a result, live variable analysis can handle them
because they are one-word objects.
This CL will change how AUTOs are described in DWARF information.
Consider the code:
func f(s string, i int) int {
x := s[i:i+5]
g()
return lookup(x)
}
The old compiler would spill x to two consecutive slots on the stack,
both named x (at offsets 0 and 8). The new compiler spills the pointer
of x to a slot named x.ptr. It doesn't spill x.len at all, as it is a
constant (5) and can be rematerialized for the call to lookup.
So compound objects may not be spilled in their entirety, and even if
they are they won't necessarily be contiguous. Such is the price of
optimization.
Re-enable live variable analysis tests. One test remains disabled, it
fails because of #14904.
Change-Id: I8ef2b5ab91e43a0d2136bfc231c05d100ec0b801
Reviewed-on: https://go-review.googlesource.com/21233
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: David Chase <drchase@google.com>
Keith Randall [Wed, 23 Mar 2016 17:20:44 +0000 (10:20 -0700)]
cmd/compile: extend prove pass to handle constant comparisons
Find comparisons to constants and propagate that information
down the dominator tree. Use it to resolve other constant
comparisons on the same variable.
So if we know x >= 7, then a x > 4 condition must return true.
This change allows us to use "_ = b[7]" hints to eliminate bounds checks.
Fixes #14900
Change-Id: Idbf230bd5b7da43de3ecb48706e21cf01bf812f7
Reviewed-on: https://go-review.googlesource.com/21008 Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Add a constant for the magic -1 for slice bounds.
Use it.
Enforce more aggressively that bounds must be
slice, ddd, or non-negative.
Remove ad hoc check in plive.go.
Check bounds before constructing an array type
when typechecking.
Keith Randall [Tue, 29 Mar 2016 04:45:33 +0000 (21:45 -0700)]
cmd/compile: place combined loads at the location of the last byte load
We need to make sure all the bounds checks pass before issuing
a load which combines several others. We do this by issuing the
combined load at the last load's block, where "last" = closest to
the leaf of the dominator tree.
Previously, cmd/compile rejected constant int->string conversions if
the integer value did not fit into an "int" value. Also, runtime
incorrectly truncated 64-bit values to 32-bit before checking if
they're a valid Unicode code point. According to the Go spec, both of
these cases should instead yield "\uFFFD".
Brad Fitzpatrick [Wed, 30 Mar 2016 05:41:18 +0000 (16:41 +1100)]
crypto/x509: add SystemCertPool, refactor system cert pool loading
This exports the system cert pool.
The system cert loading was refactored to let it be run multiple times
(so callers get a copy, and can't mutate global state), and also to
not discard errors.
SystemCertPool returns an error on Windows. Maybe it's fixable later,
but so far we haven't used it, since the system verifies TLS.
Matthew Dempsky [Thu, 31 Mar 2016 05:56:00 +0000 (22:56 -0700)]
cmd/link: remove -H elf flag
We create appropriate ELF files automatically based on GOOS. There's
no point in supporting -H elf flag, particularly since we need to emit
different flavors of ELF depending on GOOS anyway.
If that weren't reason enough, -H elf appears to be broken since at
least Go 1.4. At least I wasn't able to find a way to make use of it.
As best I can tell digging through commit history, -H elf is just an
artifact leftover from Plan 9's 6l linker.
Brad Fitzpatrick [Thu, 31 Mar 2016 05:11:41 +0000 (22:11 -0700)]
net/http: allow Handlers to handle http2 upgrade PRI requests
The http2 spec defines a magic string which initates an http2 session:
"PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n"
It was intentionally chosen to kinda look like an HTTP request, but
just different enough to break things not ready for it. This change
makes Go ready for it.
Notably: Go now accepts the request header (the prefix "PRI *
HTTP/2.0\r\n\r\n") as a valid request, even though it doesn't have a
Host header. But we now mark it as "Connection: close" and teach the
Server to never read a second request from the connection once that's
seen. If the http.Handler wants to deal with the upgrade, it has to
hijack the request, read out the "body", compare it against
"SM\r\n\r\n", and then speak http2. One of the new tests demonstrates
that hijacking.
Brad Fitzpatrick [Thu, 31 Mar 2016 03:33:46 +0000 (14:33 +1100)]
net/http: validate transmitted header fields
This makes sure the net/http package never attempts to transmit a
bogus header field key or value and instead fails fast with an error
to the user, rather than relying on the server to maybe return an
error.
It's still possible to use x/net/http2.Transport directly to send
bogus stuff. This change only stops h1 & h2 usage via the net/http
package. A future change will update x/net/http2.
This change also moves some code from request.go to lex.go, which in a
separate future change should be moved so it can be shared with http2
to reduce code bloat.
Nigel Tao [Thu, 24 Mar 2016 04:34:45 +0000 (15:34 +1100)]
image/jpeg: reconstruct progressive images even if incomplete.
Fixes #14522.
As I said on that issue:
----
This is a progressive JPEG image. There are two dimensions of
progressivity: spectral selection (variables zs and ze in scan.go,
ranging in [0, 63]) and successive approximation (variables ah and al in
scan.go, ranging in [0, 8), from LSB to MSB, although ah=0 implicitly
means ah=8).
For this particular image, there are three components, and the SOS
markers contain this progression:
The combination of all of these is complete (i.e. spectra 0 to 63 and
bits 8 exclusive to 0) for components 1 and 2, but it is incomplete for
component 0 (the luma component). In particular, there is no data for
component 0, spectra 11 to 63 and bits 1 exclusive to 0.
The image/jpeg code, as of Go 1.6, waits until both dimensions are
complete before performing the de-quantization, IDCT and copy to an
*image.YCbCr. This is the "if zigEnd != blockSize-1 || al != 0 { ...
continue }" code and associated commentary in scan.go.
Almost all progressive JPEG images end up complete in both dimensions
for all components, but this particular image is incomplete for
component 0, so the Go code never writes anything to the Y values of the
resultant *image.YCbCr, which is why the broken output is so dark (but
still looks recognizable in terms of red and blue hues).
My reading of the ITU T.81 JPEG specification (Annex G) doesn't
explicitly say that this is a valid image, but it also doesn't rule it
out.
In any case, the fix is, for progressive JPEG images, to always
reconstruct the decoded blocks (by performing the de-quantization, IDCT
and copy to an *image.YCbCr), regardless of whether or not they end up
complete. Note that, in Go, the jpeg.Decode function does not return
until the entire image is decoded, so we still only want to reconstruct
each block once, not once per SOS (Start Of Scan) marker.
----
A test image was also added, based on video-001.progressive.jpeg. When
decoding that image, inserting a
In other words, video-001.progressive.jpeg contains 10 different scans.
This little program below drops half of them (remembering to keep the
"\xff\xd9" End of Image marker):
Dave Cheney [Wed, 30 Mar 2016 23:30:04 +0000 (10:30 +1100)]
cmd/compile/internal/gc: don't iterate over field list twice
In tostruct0 and tofunargs we take a list of nodes, transform them into
a slice of Fields, set the fields on a type, then use the IterFields
iterator to iterate over the list again to see if any of them are
broken.
As we know the slice of fielde-we just created it-we can combine these two
interations into one pass over the fields.
Alexandru Moșoi [Thu, 24 Mar 2016 21:46:37 +0000 (22:46 +0100)]
cmd/compile: generalize strength reduction of mulq
* This is an improved version of an earlier patch.
* Verified with gcc up to 100.
* Limited to two instructions based on costs from
https://gmplib.org/~tege/x86-timing.pdf
Change-Id: Ib7c37de6fd8e0ba554459b15c7409508cbcf6728
Reviewed-on: https://go-review.googlesource.com/21103 Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Matthew Dempsky [Wed, 30 Mar 2016 21:45:47 +0000 (14:45 -0700)]
cmd/compile: get rid of redundant Type helper functions
Replace Isfixedarray, Isslice, and Isinter with the IsArray, IsSlice,
and IsInterface methods added for SSA. Rewrite performed mechanically
using gofmt -w -r "Isfoo(t) -> t.IsFoo()".
Because the IsFoo methods panic when given a nil pointer, a handful of
call sites had to be modified to check for nil Type values. These
aren't strictly necessary, because nil Type values should only occur
in invalid Go source programs, so it would be okay if we panicked on
them and gave up type checking the rest of the package. However, there
are a couple regress tests that expect we continue, so add checks to
keep those tests passing. (See #15029.)
This removes almost all direct access to
Type’s heavily overloaded Type field.
Mostly generated by eg, manually checked.
Significant manual changes:
* reflect.go's typPkg used Type indiscriminately.
Use it only for specific etypes.
* gen.go's visitComponents contained a usage of Type
with structs. Using Type for structs no longer
occurs, and the Fatal contained therein has not triggered,
so it has been axed.
* Scary code in cgen.go's cgen_slice is now explicitly scary.
Matthew Dempsky [Mon, 28 Mar 2016 17:55:44 +0000 (10:55 -0700)]
cmd/compile: rename Type.IsPtr to Type.IsPtrShaped
Previously, t.IsPtr() reported whether t was represented with a
pointer, but some of its callers expected it to report whether t is an
actual Go pointer. Resolve this by renaming t.IsPtr to t.IsPtrShaped
and adding a new t.IsPtr method to report Go pointer types.
Updated a couple callers in gc/ssa.go to use IsPtr instead of
IsPtrShaped.
cmd/compile: use IsSlice and IsArray instead of checking Bound
Changes generated by eg and manually checked.
Isfixedarray, Isslice, and many other
Type-related functions in subr.go should
either be deleted or moved to type.go.
Later, though; the game now is cleanup via encapsulation.
Michael Munday [Tue, 29 Mar 2016 15:39:33 +0000 (11:39 -0400)]
cmd/asm: add s390x support
s390x doesn't introduce any new assembly syntax. There are a few
instructions which require the operands to be reordered, notably
the storage-storage instructions that put the length into From3 so
that the memory operands can be put into From and To.
The assembly test currently covers a subset of instructions but
tries to hit edge cases as much as possible. Unlike the other ports
it can be linked as an executable to make disassembling it easy.
It would be nice to autogenerate it at some point in the future.
Michael Munday [Fri, 18 Mar 2016 23:23:50 +0000 (19:23 -0400)]
cmd/internal/obj/s390x: add s390x support
Based on the ppc64 port.
s390x supports 2, 4 and 6 byte instructions and Go assembly
instructions sometimes map to several s390x instructions. The
assembler loops until a fixed point is reached in order to use
branch instructions that can only handle a short offset in a
similar way to other ports.
Keith Randall [Tue, 29 Mar 2016 23:39:53 +0000 (16:39 -0700)]
cmd/compile: define high bits of AuxInt
Previously if we were only using the low bits of AuxInt,
the high bits were ignored and could be junk. This CL
changes that behavior to define the high bits to be the
sign-extended version of the low bits for all cases.
There are 2 main benefits:
- Deterministic representation. This helps with CSE.
(Const8 [0x1]) and (Const8 [0x101]) used to be the same "value"
but CSE couldn't see them as such.
- Testability. We can check that all ops leave AuxInt in a state
consistent with the new rule. In the old scheme, it was hard
to check whether a rule correctly used only the low-order bits.
Side benefits:
- ==0 and !=0 tests are easier.
Drawbacks:
- This differs from the runtime representation in registers,
where it is important that we allow upper bits to be undefined
(so we're not sign/zero-extending all the time).
- Ops that treat AuxInt as unsigned (shifts, mostly) need to be
a bit more careful.
Brad Fitzpatrick [Wed, 30 Mar 2016 03:27:24 +0000 (14:27 +1100)]
net/http: reuse HTTP/1 Transport conns more for gzipped responses
Flip around the composition order of the http.Response.Body's
gzip.Reader vs. the reader which keeps track of waiting to see the end
of the HTTP/1 response framing (whether that's a Content-Length or
HTTP/1.1 chunking).
But because bodyEOFSignal was waiting to see an EOF from the
underlying gzip.Reader before reusing the connection, and gzip.Reader
(or more specifically: the flate.Reader) wasn't returning an early
io.EOF with the final chunk, the bodyEOfSignal was never releasing the
connection, because the EOF from the http1 framing was read by a party
who didn't care about it yet: the helper bufio.Reader created to do
byte-at-a-time reading in the flate.Reader.
Now when gzip.Reader does its byte-at-a-time reading via the
bufio.Reader, the bufio.Reader will do its big reads against the
bodyEOFSignal reader instead, which will then see the underlying http1
framing EOF, and be able to reuse the connection.
Updates google/go-github#317
Updates #14867
And related abandoned fix to flate.Reader: https://golang.org/cl/21290
Shahar Kohanim [Tue, 22 Mar 2016 22:44:07 +0000 (00:44 +0200)]
cmd/compile, cmd/link: record lengths in object file
Record total number of relocations, pcdata, automatics, funcdata and files in
object file and use these numbers in the linker to allocate contiguous
slices to later be filled by the defined symbols.
name old secs new secs delta
LinkCmdGo 0.52 ± 3% 0.49 ± 3% -4.21% (p=0.000 n=91+92)
LinkJuju 4.48 ± 4% 4.21 ± 7% -6.08% (p=0.000 n=96+100)
name old MaxRSS new MaxRSS delta
LinkCmdGo 122k ± 2% 120k ± 4% -1.66% (p=0.000 n=98+93)
LinkJuju 799k ± 5% 865k ± 8% +8.29% (p=0.000 n=89+99)
GOGC=off
name old secs new secs delta
LinkCmdGo 0.42 ± 2% 0.41 ± 0% -2.98% (p=0.000 n=89+70)
LinkJuju 3.61 ± 0% 3.52 ± 1% -2.46% (p=0.000 n=80+89)
name old MaxRSS new MaxRSS delta
LinkCmdGo 130k ± 1% 128k ± 1% -1.33% (p=0.000 n=100+100)
LinkJuju 1.00M ± 0% 0.99M ± 0% -1.70% (p=0.000 n=100+100)
Change-Id: Ie08f6ccd4311bb78d8950548c678230a58635c73
Reviewed-on: https://go-review.googlesource.com/21026 Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
cmd/compile: add typArray, typSlice, and typDDDArray
These are the first of several convenience
constructors for types.
They are part of type field encapsulation.
This removes most external writes to TARRAY Type and Bound fields.
substAny still directly fiddles with the .Type field.
substAny generally needs access to Type internals.
It will be moved to type.go in a future CL.
bimport still directly writes the .Type field.
This is hard to change.
Also of note:
* inl.go contains an (apparently irrelevant) bug fix:
as.Right was given the wrong type.
vararrtype was previously unused.
* I believe that aindex (subr.go) never creates slices,
but it is safer to keep existing behavior.
The removal of -1 as a constant there is part
of hiding that implementation detail.
Future CLs will finish that job.
Aliaksandr Valialkin [Tue, 22 Mar 2016 13:38:21 +0000 (15:38 +0200)]
cmd/vet: improve detecting printf-like format argument
Previously format argument was detected via scanning func type args.
This didn't work when func type couldn't be determined if the func
is declared in the external package. Fall back to scanning for
the first string call argument in this case.
Fixes #14754
Change-Id: I571cc29684cc641bc87882002ef474cf1481e9e2
Reviewed-on: https://go-review.googlesource.com/21023
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Marvin Stenger [Tue, 29 Mar 2016 12:09:22 +0000 (14:09 +0200)]
all: use &^ operator if possible
This is a change improving consistency in the source tree.
The pattern foo &= ^bar, was only used six times in src/ directory.
The usage of the supported &^ (bit clear / AND NOT) operator is way more
common, about factor 10x.
Change-Id: If26a2994fd81d23d42189bee00245eb84e672cf3
Reviewed-on: https://go-review.googlesource.com/21224 Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Klaus Post [Mon, 21 Mar 2016 13:51:28 +0000 (14:51 +0100)]
compress/flate: add pure huffman deflater
Add a "HuffmanOnly" compression level, where the input is
only entropy encoded.
The output is fully inflate compatible. Typical compression
is reduction is about 50% of typical level 1 compression, however
the compression time is very stable, and does not vary as much as
nearly as much level 1 compression (or Snappy).
This mode is useful for:
* HTTP compression in a CPU limited environment.
* Entropy encoding Snappy compressed data, for archiving, etc.
* Compression where compression time needs to be predictable.
* Fast network transfer.
Snappy "usually" performs inbetween this and level 1 compression-wise,
but at the same speed as "Huffman", so this is not a replacement,
but a good supplement for Snappy, since it usually can compress
Snappy output further.
This is implemented as level -2, since this would be too much of a
compression reduction to replace level 1.
Alex Brainman [Sun, 20 Mar 2016 10:12:38 +0000 (21:12 +1100)]
path/filepath: use fsutil with TestEvalSymlinksCanonicalNames
TestEvalSymlinksCanonicalNames fails on system where 8dot3 name creation
is disabled. Add new test that temporarily changes 8dot3 name creation
file system setting and runs TestEvalSymlinksCanonicalNames under that
setting. New test requires administrator access and modifies important
file system setting, so don't run the test unless explicitly requested
by specifying new test flag.
which are erroneous because NAME_AUTO implies a base register of
REG_SP, and cmd/internal/obj/x86 makes many assumptions to this
effect. Note that previously we were also producing an extra "ADDQ
SP, CX" instruction, so indexing off of SP was already handled.
The approach taken by this CL to address the problem is to instead
produce addresses like:
Downside to this approach is it requires adding a lot of new
MOV[WLQ]loadidx1 instructions that nearly duplicate functionality of
the existing MOV[WLQ]loadidx[248] instructions, but with a different
Scale.
Fixes #15001.
Change-Id: Iad9a1a41e5e2552f8d22e3ba975e4ea0862dffd2
Reviewed-on: https://go-review.googlesource.com/21245
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
Michel Lespinasse [Sat, 19 Mar 2016 00:21:33 +0000 (17:21 -0700)]
cmd/compile: optimize remaining convT2I calls
See #14874
Updates #6853
This change adds a compiler optimization for non pointer shaped convT2I.
Since itab symbols are now emitted by the compiler, the itab address can
be passed directly to convT2I instead of passing the iface type and a
cache pointer argument.
Compilebench results for the 5-commits series ending here:
Michel Lespinasse [Fri, 18 Mar 2016 23:20:20 +0000 (16:20 -0700)]
cmd/compile: optimize convT2I as a two-word copy when T is pointer-shaped
See #14874
This change adds a compiler optimization for pointer shaped convT2I.
Since itab symbols are now emitted by the compiler, the itab address can
be directly moved into the iface structure.
Change-Id: I311483af544519ca682c5f872960717ead772f26
Reviewed-on: https://go-review.googlesource.com/20901 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: David Crawshaw <crawshaw@golang.org>
Michel Lespinasse [Thu, 17 Mar 2016 13:18:13 +0000 (06:18 -0700)]
cmd/compile: emit itabs and itablinks
See #14874
This change tells the compiler to emit itab and itablink symbols in
situations where they could be useful; however the compiled code does
not actually make use of the new symbols yet.
Change-Id: I0db3e6ec0cb1f3b7cebd4c60229e4a48372fe586
Reviewed-on: https://go-review.googlesource.com/20888 Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Michel Lespinasse <walken@google.com>
Richard Miller [Sat, 26 Mar 2016 19:35:21 +0000 (19:35 +0000)]
syscall: fix accidental close of exec status pipe in StartProcess
In syscall.forkAndExecInChild, blocks of code labelled Pass 1
and Pass 2 permute the file descriptors (if necessary) which are
passed to the child process. If Pass 1 begins with fds = {0,2,1},
nextfd = 4 and pipe = 4, then the statement labelled "don't stomp
on pipe" is too late -- the pipe (which will be needed to pass
exec status back to the parent) will have been closed by the
preceding DUP call.
Moving the "don't stomp" test earlier ensures that the pipe is
protected.
Fixes #14979
Change-Id: I890c311527f6aa255be48b3277c1e84e2049ee22
Reviewed-on: https://go-review.googlesource.com/21184
Run-TryBot: David du Colombier <0intro@gmail.com> Reviewed-by: David du Colombier <0intro@gmail.com> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This mostly a mechanical change.
However, the change in assignop (subr.go) is a bug fix.
The code didn’t match the comment,
and the comment was correct.
Nevertheless, this CL passes toolstash -cmp.
The last direct reference to dddBound outside
type.go (in typecheck.go) will go away
in a future CL.
Change-Id: Ifb1691e0a07f906712c18c4a4cd23060807a5da5
Reviewed-on: https://go-review.googlesource.com/21235 Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Raul Silvera [Mon, 28 Mar 2016 20:52:28 +0000 (13:52 -0700)]
cmd/pprof/internal: use and accept packed encoding for repeated fields
Packed encoding is the default on the proto3 format. Profiles generated
in the profile.proto format by third parties cannot be decoded by the
Go pprof tool, since its proto decoder does not recognize packed
encoding for repeated fields.
In particular this issue prevents go tool pprof from reading profiles
generated by the version of pprof in github.com/google/pprof
Profiles generated by go tool pprof after this change will use packed
repeating fields, so older versions of pprof will not be able to read
them. pprof will continue to be able to read profiles generated before
this change.
Change-Id: Ife0b353a535ae1e495515b9bcec588dd967e171b
Reviewed-on: https://go-review.googlesource.com/21240 Reviewed-by: David Symonds <dsymonds@golang.org>
Run-TryBot: David Symonds <dsymonds@golang.org>
Robert Griesemer [Mon, 28 Mar 2016 21:12:10 +0000 (14:12 -0700)]
cmd/compile: avoid allocation in Nodes.Set in common case
When building make.bash, calling Nodes.Set(s) where len(s) == 0 occurs 4738678 times vs 1465415 calls where len(s) > 0; i.e., it is over 3x
more common to set Nodes.slice to nil rather than to s.
Make a copy of slice (header) and take address of that copy instead
to avoid allocating the argument slice on the heap always even when
not needed.
Saves 4738678 slice header allocations and slice header value copies.
Change-Id: I88e8e919ea9868ceb2df46173d187af4109bd947
Reviewed-on: https://go-review.googlesource.com/21241 Reviewed-by: Alan Donovan <adonovan@google.com>
Michael Munday [Sat, 19 Mar 2016 04:44:17 +0000 (00:44 -0400)]
cmd/asm: add s390x support
s390x doesn't introduce any new assembly syntax. There are a few
instructions which require the operands to be reordered, notably
the storage-storage instructions that put the length into From3 so
that the memory operands can be put into From and To.
The assembly test currently covers a subset of instructions but
tries to hit edge cases as much as possible. Unlike the other ports
it can be linked as an executable to make disassembling it easy.
It would be nice to autogenerate it at some point in the future.
Change-Id: I7615ac6ecf239e3f347fad9ae1f8eede91742859
Reviewed-on: https://go-review.googlesource.com/20934
Run-TryBot: Rob Pike <r@golang.org> Reviewed-by: Rob Pike <r@golang.org>
Shinji Tanaka [Sat, 26 Mar 2016 11:14:15 +0000 (07:14 -0400)]
runtime: use set_thread_area instead of modify_ldt on linux/386
linux/386 depends on modify_ldt system call, but recent Linux kernels
can disable this system call. Any Go programs built as linux/386
crash with the message 'Trace/breakpoint trap'.
The kernel config CONFIG_MODIFY_LDT_SYSCALL, which control
enable/disable modify_ldt, is disabled on Amazon Linux 2016.03.
This fixes this problem by using set_thread_area instead of modify_ldt
on linux/386.