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
