For simplicity, only recognizes expressions of the exact form
"(x << a) | (x >> b)" where x is a variable and a and b are
integer constant expressions that add to x's bit width.
Fixes#4629.
$ cat rotate.c
unsigned int
rotate(unsigned int x)
{
x = (x << 3) | (x >> (sizeof(x) * 8 - 3));
return x;
}
## BEFORE
$ go tool 6c -S rotate.c
(rotate.c:2) TEXT rotate+0(SB),$0-8
(rotate.c:2) MOVL x+0(FP),!!DX
(rotate.c:4) MOVL DX,!!AX
(rotate.c:4) SALL $3,!!AX
(rotate.c:4) MOVL DX,!!CX
(rotate.c:4) SHRL $29,!!CX
(rotate.c:4) ORL CX,!!AX
(rotate.c:5) RET ,!!
(rotate.c:5) RET ,!!
(rotate.c:5) END ,!!
## AFTER
$ go tool 6c -S rotate.c
(rotate.c:2) TEXT rotate+0(SB),$0-8
(rotate.c:4) MOVL x+0(FP),!!AX
(rotate.c:4) ROLL $3,!!AX
(rotate.c:5) RET ,!!
(rotate.c:5) RET ,!!
(rotate.c:5) END ,!!
R=rsc, minux.ma
CC=golang-dev
https://golang.org/cl/7069056
If the scanned block has no typeinfo the garbage collector will attempt
to get the actual type of the block.
R=golang-dev, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/7093045
On Plan 9, only the parent of a given process can enter its wait
queue. When a Go program tries to fork-exec a child process
and subsequently waits for it to finish, the goroutines doing
these two tasks do not necessarily tie themselves to the same
(or any single) OS thread. In the case that the fork and the wait
system calls happen on different OS threads (say, due to a
goroutine being rescheduled somewhere along the way), the
wait() will either return an error or end up waiting for a
completely different child than was intended.
This change forces the fork and wait syscalls to happen in the
same goroutine and ties that goroutine to its OS thread until
the child exits. The PID of the child is recorded upon fork and
exit, and de-queued once the child's wait message has been read.
The Wait API, then, is translated into a synthetic implementation
that simply waits for the requested PID to show up in the queue
and then reads the associated stats.
R=rsc, rminnich, npe, mirtchovski, ality
CC=golang-dev
https://golang.org/cl/6545051
The test case of issue 4585 was not passing due to
miscalculation of memequal args, and the previous fix
does not handle padding at the end of a struct.
Handling of padding at end of structs also fixes the case
of [n]T where T is such a padded struct.
Fixes#4585.
(again)
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7133059
Reference the 80386 compiler documentation now that the
documentation for the 68020 is offline.
R=golang-dev, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7127053
sse2 is a more precise description of the requirement,
and it matches what people will see in, for example
grep sse2 /proc/cpuinfo # linux
sysctl hw.optional.sse2 # os x
R=golang-dev, dsymonds, iant
CC=golang-dev
https://golang.org/cl/7057050
Decode as much as possible of a Huffman symbol in a single table
lookup (much like the zlib implementation), filling more bits
(conservatively, so we don't consume past the end of the stream)
when the code prefix indicates more bits are needed. This
results in about a 50% performance gain in speed benchmarks.
The following set is benchcmp done on a retina MacBook Pro:
benchmark old MB/s new MB/s speedup
BenchmarkDecodeDigitsSpeed1e4 28.41 42.79 1.51x
BenchmarkDecodeDigitsSpeed1e5 30.18 47.62 1.58x
BenchmarkDecodeDigitsSpeed1e6 30.81 48.14 1.56x
BenchmarkDecodeDigitsDefault1e4 30.28 44.61 1.47x
BenchmarkDecodeDigitsDefault1e5 32.18 51.94 1.61x
BenchmarkDecodeDigitsDefault1e6 35.57 53.28 1.50x
BenchmarkDecodeDigitsCompress1e4 30.39 44.83 1.48x
BenchmarkDecodeDigitsCompress1e5 33.05 51.64 1.56x
BenchmarkDecodeDigitsCompress1e6 35.69 53.04 1.49x
BenchmarkDecodeTwainSpeed1e4 25.90 43.04 1.66x
BenchmarkDecodeTwainSpeed1e5 29.97 48.19 1.61x
BenchmarkDecodeTwainSpeed1e6 31.36 49.43 1.58x
BenchmarkDecodeTwainDefault1e4 28.79 45.02 1.56x
BenchmarkDecodeTwainDefault1e5 37.12 55.65 1.50x
BenchmarkDecodeTwainDefault1e6 39.28 58.16 1.48x
BenchmarkDecodeTwainCompress1e4 28.64 44.90 1.57x
BenchmarkDecodeTwainCompress1e5 37.40 55.98 1.50x
BenchmarkDecodeTwainCompress1e6 39.35 58.06 1.48x
R=rsc, dave, minux.ma, bradfitz, nigeltao
CC=golang-dev
https://golang.org/cl/6872063
Calling it will show memory allocation statistics for that
single benchmark (if -test.benchmem is not provided)
R=golang-dev, rsc, kevlar, bradfitz
CC=golang-dev
https://golang.org/cl/7027046
I think that the parser is complete enough to take that warning out.
It passes the test suite.
There may be incompatible API changes, but being in the exp directory
is warning enough for that.
R=nigeltao
CC=golang-dev
https://golang.org/cl/7131050
We need to wait for the handler to actually finish running,
not almost be done running.
This was always a bug, but now that handler output is buffered
it shows up easily on GOMAXPROCS >1 systems.
R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7109043
- always set the Pkg field in QualifiedIdents
- call Context.Ident for all identifiers in the AST that denote
a types.Object (bug fix)
- added test that Context.Ident is called for all such identifiers
R=adonovan
CC=golang-dev
https://golang.org/cl/7101054
Completely removed *ast.Objects from being exposed by the
types API. *ast.Objects are still required internally for
resolution, but now the door is open for an internal-only
rewrite of identifier resolution entirely at type-check
time. Once that is done, ASTs can be type-checked whether
they have been created via the go/parser or otherwise,
and type-checking does not require *ast.Object or scope
invariants to be maintained externally.
R=adonovan
CC=golang-dev
https://golang.org/cl/7096048
Also undo revision a5b96b602690 used to workaround the bug.
Fixes#4643.
R=rsc, golang-dev, dave, minux.ma, lucio.dere, bradfitz
CC=golang-dev
https://golang.org/cl/7090043
The existing type checker was relying on augmenting ast.Object
fields (empty interfaces) for its purposes. While this worked
for some time now, it has become increasingly brittle. Also,
the need for package information for Fields and Methods would
have required a new field in each ast.Object. Rather than making
them bigger and the code even more subtle, in this CL we are moving
away from ast.Objects.
The types packge now defines its own objects for different
language entities (Const, Var, TypeName, Func), and they
implement the types.Object interface. Imported packages
create a Package object which holds the exported entities
in a types.Scope of types.Objects.
For type-checking, the current package is still using ast.Objects
to make this transition manageable. In a next step, the type-
checker will also use types.Objects instead, which opens the door
door to resolving ASTs entirely by the type checker. As a result,
the AST and type checker become less entangled, and ASTs can be
manipulated "by hand" or programmatically w/o having to worry
about scope and object invariants that are very hard to maintain.
(As a consequence, a future parser can do less work, and a
future AST will not need to define objects and scopes anymore.
Also, object resolution which is now split across the parser,
the ast, (ast.NewPackage), and even the type checker (for composite
literal keys) can be done in a single place which will be simpler
and more efficient.)
Change details:
- Check now takes a []*ast.File instead of a map[string]*ast.File.
It's easier to handle (I deleted code at all use sites) and does
not suffer from undefined order (which is a pain for testing).
- ast.Object.Data is now a *types.Package rather then an *ast.Scope
if the object is a package (obj.Kind == ast.Pkg). Eventually this
will go away altogether.
- Instead of an ast.Importer, Check now uses a types.Importer
(which returns a *types.Package).
- types.NamedType has two object fields (Obj Object and obj *ast.Object);
eventually there will be only Obj. The *ast.Object is needed during
this transition since a NamedType may refer to either an imported
(using types.Object) or locally defined (using *ast.Object) type.
- ast.NewPackage is not used anymore - there's a local copy for
package-level resolution of imports.
- struct fields now take the package origin into account.
- The GcImporter is now returning a *types.Package. It cannot be
used with ast.NewPackage anymore. If that functionality is still
used, a copy of the old GcImporter should be made locally (note
that GcImporter was part of exp/types and it's API was not frozen).
- dot-imports are not handled for the time being (this will come back).
R=adonovan
CC=golang-dev
https://golang.org/cl/7058060
This introduces a buffer between writing from a handler and
writing chunks. Further, it delays writing the header until
the first full chunk is ready. In the case where the first
full chunk is also the final chunk (for small responses), that
means we can also compute a Content-Length, which is a nice
side effect for certain benchmarks.
Fixes#2357
R=golang-dev, dave, minux.ma, rsc, adg, balasanjay
CC=golang-dev
https://golang.org/cl/6964043
The peephole optimizer would keep hands off AX and X0 during returns, even though go doesn't return through registers.
R=dave, rsc
CC=golang-dev
https://golang.org/cl/7030046
Changeset f483bfe81114 moved ELF generation to the architecture
independent code and in doing so added a Section* to the Sym
type and an Elf64_Shdr* to the Section type.
This caused the Plan 9 compilers to complain about incompatible
type signatures in the many files that reference the Sym type.
R=rsc, dave
CC=golang-dev
https://golang.org/cl/7057058
Fixes#4186.
Back in the day, before the Go 1.0 release, $GOROOT was mandatory for building from source. Fast forward to now and $GOPATH is mandatory and $GOROOT is optional, and mainly used by those who use the binary distribution in uncommon places.
For example, most novices at least know about `sudo` as they would have used it to install the binary tarball into /usr/local. It is logical they would use the `sudo` hammer to `go get` other Go packages when faced with a permission error talking about the path they just had to use `sudo` on last time.
Even if they had read the documentation and set $GOPATH, go get will not work as expected as `sudo` masks most environment variables.
llucky(~) % ~/go/bin/go env | grep GOPATH
GOPATH="/home/dfc"
lucky(~) % sudo ~/go/bin/go env | grep GOPATH
GOPATH=""
This CL therefore proposes to remove support for using `go get` to download source into $GOROOT.
This CL also proposes an error when GOPATH=$GOROOT, as this is another place where new Go users can get stuck.
Further discussion: https://groups.google.com/d/topic/golang-nuts/VIg3fjHiHRI/discussion
R=rsc, adg, minux.ma
CC=golang-dev
https://golang.org/cl/6941058
The linker split PKGDEF into (prefix, name, def) pairs,
and defines def to begin after a space following the identifier.
This is totally wrong for the following export data:
func "".FunctionName()
var SomethingCompletelyUnrelated int
The linker would parse
name=`"".FunctionName()\n\tvar`
def=`SomethingCompletelyUnrelated int`
since there is no space after FunctionName.
R=minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7068051
Our source no longer needs these flags set to build cleanly using clang.
Tested with
* Ubuntu clang version 3.0-6ubuntu3 (tags/RELEASE_30/final) (based on LLVM 3.0) on i386
* clang version 3.2 (tags/RELEASE_32/final) on amd64 cross compiling all platforms
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7058053
The old code made it impossible to implement a reverse proxy
with anything less than 4k write granularity to the backends.
R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/7060059
A constant node of type uintptr with a nil literal could
happen in two cases: []int(nil)[1:] and
uintptr(unsafe.Pointer(nil)).
Fixes#4614.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7059043
There exists a test case for this condition, but it only runs on unix systems, which neatly dovetails into the code always using ':' as the list separator.
R=adg, iant
CC=golang-dev
https://golang.org/cl/7057052
ratio isn't 1x1.
Fixes#4259.
The test data was generated by
cjpeg -quality 50 -sample 2x2 video-005.gray.pgm > video-005.gray.q50.2x2.jpeg
cjpeg -quality 50 -sample 2x2 -progressive video-005.gray.pgm > video-005.gray.q50.2x2.progressive.jpeg
similarly to video-005.gray.q50.* from
http://code.google.com/p/go/source/detail?r=51f26e36ba98
the key difference being the "-sample 2x2".
R=rsc
CC=golang-dev
https://golang.org/cl/7069045
There's no b in race detector.
The new flag matches the one in the go command
(go test -race math).
R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/7072043
bytes.Equal is simpler to read and should also be faster because
of short-circuiting and assembly implementations.
Change generated automatically using:
gofmt -r 'bytes.Compare(a, b) == 0 -> bytes.Equal(a, b)'
gofmt -r 'bytes.Compare(a, b) != 0 -> !bytes.Equal(a, b)'
R=golang-dev, dave, adg, rsc
CC=golang-dev
https://golang.org/cl/7038051
Closures are incredibly expensive on linux/arm due to
repetitive flush of instruction cache.
go test -short on ODROID-X:
Before:
ok exp/gotype 17.091s
ok go/types 2.225s
After:
ok exp/gotype 7.193s
ok go/types 1.143s
R=dave, minux.ma, rsc
CC=golang-dev, remy
https://golang.org/cl/7062045
This CL adds a flag parser that matches the semantics of Go's
package flag. It also changes the linkers and compilers to use
the new flag parser.
Command lines that used to work, like
8c -FVw
6c -Dfoo
5g -I/foo/bar
now need to be split into separate arguments:
8c -F -V -w
6c -D foo
5g -I /foo/bar
The new spacing will work with both old and new tools.
The new parser also allows = for arguments, as in
6c -D=foo
5g -I=/foo/bar
but that syntax will not work with the old tools.
In addition to matching standard Go binary flag parsing,
the new flag parser generates more detailed usage messages
and opens the door to long flag names.
The recently added gc flag -= has been renamed -complete.
R=remyoudompheng, daniel.morsing, minux.ma, iant
CC=golang-dev
https://golang.org/cl/7035043
More cleanup in preparation for fixing issue 4069.
This CL replaces the three nearly identical copies of the
asmb ELF code with a single asmbelf function in elf.c.
In addition to the ELF code movement, remove the elfstr
array in favor of a simpler lookup, and identify sections by
name throughout instead of computing fragile indices.
The CL also replaces the three nearly identical copies of the
genasmsym code with a single genasmsym function in lib.c.
The ARM linker still compiles and generates binaries,
but I haven't tested the binaries. They may not work.
R=ken2
CC=golang-dev
https://golang.org/cl/7062047
The Plan 9 symbol table format defines big-endian symbol values
for portability, but we want to be able to generate an ELF object file
and let the host linker link it, as part of the solution to issue 4069.
The symbol table itself, since it is loaded into memory at run time,
must be filled in by the final host linker, using relocation directives
to set the symbol values. On a little-endian machine, the linker will
only fill in little-endian values during relocation, so we are forced
to use little-endian symbol values.
To preserve most of the original portability of the symbol table
format, we make the table itself say whether it uses big- or
little-endian values. If the table begins with the magic sequence
fe ff ff ff 00 00
then the actual table begins after those six bytes and contains
little-endian symbol values. Otherwise, the table is in the original
format and contains big-endian symbol values. The magic sequence
looks like an "end of table" entry (the fifth byte is zero), so legacy
readers will see a little-endian table as an empty table.
All the gc architectures are little-endian today, so the practical
effect of this CL is to make all the generated tables little-endian,
but if a big-endian system comes along, ld will not generate
the magic sequence, and the various readers will fall back to the
original big-endian interpretation.
R=ken2
CC=golang-dev
https://golang.org/cl/7066043
A few USED(xxx) additions and a couple of deletions of variable
initialisations that go unused. One questionable correction,
mirrored in 8l/asm.c, where the result of invocation of a function
shouldn't be used.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6736054
RFC5424 specifies a version number (currently 1) after the facility and
severity in a syslog message (e.g. <7>1 TIMESTAMP ...). This causes
rsyslog to fail to parse syslog message because the rest of the message
is not fully compliant with RFC5424.
For the widest compatibility, drop the version (messages are in the
RFC3164 BSD syslog format (e.g. <7>TIMESTAMP ...). Have tested this with
syslog-ng, rsyslog and syslogd.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7036050
TimeoutHandler was changed from "ns int64" to "dt time.Duration" on
Nov 30, 2011, but the godoc still refers to "ns".
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7031050
* Extended deadline to 30 seconds
* Added logging of the duration of each package import
* Fail the test immediately if directories cannot be read
R=gri, minux.ma
CC=golang-dev
https://golang.org/cl/7030055
It already did so for its sibling, *strings.Reader, as well as *bytes.Buffer.
R=edsrzf, dave, adg, kevlar, remyoudompheng, adg, rsc
CC=golang-dev
https://golang.org/cl/7031045
Add a check for this case and don't try to follow the anonymous
type's non-existent fields.
Fixes#4474.
R=rsc
CC=golang-dev
https://golang.org/cl/6945065
Request.URL had no documentation before and some people were expecting all fields to be populated.
Fixes#3805.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7008046
A new environment variable GO386 is introduced to choose between
code generation targeting 387 or SSE2. No auto-detection is
performed and the setting defaults to 387 to preserve previous
behaviour.
The patch is a reorganization of CL6549052 by rsc.
Fixes#3912.
R=minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6962043
Unnamed types like structs with embedded fields can have methods.
These methods are generated on-the-fly by the compiler and
it may happen for identical types in different packages.
The linker must accept these multiple definitions.
Fixes#4590.
R=golang-dev, rsc
CC=golang-dev, remy
https://golang.org/cl/7030051
sysarch requires arguments to be passed on the stack, not in registers.
Credit to Shenghou Ma (minux) for the fix.
R=minux.ma, devon.odell
CC=golang-dev
https://golang.org/cl/7037043
Under FreeBSD-CURRENT on arm, cgo enabled binaries segfault. Disable cgo support for the moment so we can have a freebsd/arm builder on the dashboard.
R=minux.ma, rsc, iant
CC=golang-dev
https://golang.org/cl/7031044
Allows encoding and decoding of maps with key of string kind, not just string type.
Fixes#3519.
R=rsc, dave
CC=golang-dev
https://golang.org/cl/6943047
Used to then die on a nil pointer situation. Most Linux standard setups are rather
restrictive regarding the default amount of lockable memory.
R=minux.ma, rsc
CC=golang-dev
https://golang.org/cl/6997049
While half of all numbers don't have their most-significant bit set,
this is becoming increasingly impermissible for RSA moduli. In an
attempt to exclude weak keys, several bits of software either do, or
will, enforce that RSA moduli are >= 1024-bits.
However, Go often generates 1023-bit RSA moduli which this software
would then reject.
This change causes crypto/rsa to regenerate the primes in the event
that the result is shorter than requested.
It also alters crypto/rand in order to remove the performance impact
of this:
The most important change to crypto/rand is that it will now set the
top two bits in a generated prime (OpenSSL does the same thing).
Multiplying two n/2 bit numbers, where each have the top two bits set,
will always result in an n-bit product. (The effectively makes the
crypto/rsa change moot, but that seems too fragile to depend on.)
Also this change adds code to crypto/rand to rapidly eliminate some
obviously composite numbers and reduce the number of Miller-Rabin
tests needed to generate a prime.
R=rsc, minux.ma
CC=golang-dev
https://golang.org/cl/7002050
- introduced type Method for methods
- renamed StructField -> Field
- removed ObjList
- methods are not sorted anymore in interfaces (for now)
R=adonovan
CC=golang-dev
https://golang.org/cl/7023043
This is a just a file move with no other changes
besides the manual import path adjustments in these
two files:
src/pkg/exp/gotype/gotype.go
src/pkg/exp/gotype/gotype_test.go
Note: The go/types API continues to be subject to
possibly significant changes until Go 1.1. Do not
rely on it being stable at this point.
R=adonovan
CC=golang-dev
https://golang.org/cl/7013049
The parser/resolver cannot accurately resolve
composite literal keys that are identifiers;
it needs type information.
Instead, try to resolve them but leave final
judgement to the type checker.
R=adonovan
CC=golang-dev
https://golang.org/cl/6994047
These files are identical, so probably pre date // +build.
With a little work, fd_darwin could be merged as well.
R=mikioh.mikioh, jsing, devon.odell, lucio.dere, minux.ma
CC=golang-dev
https://golang.org/cl/7004053
The new garbage collector (CL 6114046) may find the fake *[]byte value
and interpret its contents as bytes rather than as potential pointers.
This may lead the garbage collector to free memory blocks that
shouldn't be freed.
R=dvyukov, rsc, dave, minux.ma, remyoudompheng, iant
CC=golang-dev
https://golang.org/cl/7000059
Proper local system log semantics still need to be
created for Plan 9. In the meantime, the test suite
(viz., exp/gotype) expects there to be some Go
source for each import path. Thus, here is a stub,
equivalent to syslog_windows, for this purpose.
R=golang-dev, rsc, alex.brainman
CC=golang-dev
https://golang.org/cl/7000062
- added Context type for configuration of type checker
- type check all function and method bodies
- (partial) fixes to shift hinting (still not complete)
- revamped test harness - does not rely on specific position
representation anymore, just a standard (compiler) error
message
- lots of bug fixes
R=adonovan, rsc
CC=golang-dev
https://golang.org/cl/6948071
