Commit Graph

20 Commits

Author SHA1 Message Date
Dominik Honnef a99f4ece36 go/pointer: implement extended queries
The existing API for querying values only allows directly querying
pointer-like values, or pointers to such values. The new, extended
queries make it possible to destructure values and access arbitrarily
nested pointers, such as fields in structs, or specific values in
tuples.

We use single Go expressions as the queries, which we further restrict
to a subset of the language (indexing, field access, pointer
dereferences and channel receives).

Instead of adding another map to Result, we return a *Pointer and
populate it during analysis. This does mean that a Config cannot be
reused for multiple analyses, as it now holds analysis-specific state.
That is, however, not a big problem as reusing one Config had little
use.

Since the new API can do everything the old could, it deprecates
AddQuery and AddIndirectQuery.

Change-Id: I4b2ae7d85c462bc7faa6bab76456106e76be5a65
Reviewed-on: https://go-review.googlesource.com/37635
Reviewed-by: Alan Donovan <adonovan@google.com>
2017-03-06 04:11:41 +00:00
David R. Jenni be0fcc31ae x/tools/go: gofmt -s -w
Change-Id: I978b981d95909f2590c1e1db05e8a95e232a67d5
Reviewed-on: https://go-review.googlesource.com/32794
Reviewed-by: Alan Donovan <adonovan@google.com>
2017-02-15 21:43:35 +00:00
Alan Donovan 2f93937767 x/tools: s/oracle/guru/g in various comments
Change-Id: Ie0da80db4f58d9f6e7d9675c89f106d1cd01710a
Reviewed-on: https://go-review.googlesource.com/30983
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-10-13 18:54:04 +00:00
Alan Donovan 0f9d71c428 go/pointer: fix bug in constraint generation of "for _, v := range map"
+ regression test

Change-Id: I9ec28f222e14af0cb737494e3c48e5423cdcf236
Reviewed-on: https://go-review.googlesource.com/16294
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-10-26 16:28:05 +00:00
Alan Donovan ce7df396da go/pointer: fix two crashes caused by 'print()'.
+ Test.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/173540043
2014-11-20 13:33:20 -05:00
Alan Donovan 11451553df go/pointer: fix panic due to bogus constraint from value,ok receive operation.
See regression test for explanation.

I audited the code for similar issues and found none.

Many thanks to Daniel Morsing for providing a small
reproducible test case, a rarity for PTA bugs!

Fixes golang/go#9002

LGTM=crawshaw
R=crawshaw
CC=daniel.morsing, golang-codereviews
https://golang.org/cl/163350043
2014-10-27 13:55:52 -04:00
Alan Donovan 4228ee8063 go.tools/go/ssa: improve printing of anonymous functions.
Examples:
- "foo$1" becomes "pkg.foo$1"
- "init$1" (meaning the first declared "init" function) becomes "init#1",
   to distinguish it from "init$1" (meaning the first anonymous function
   within the synthetic "init" function that initializes package-level vars).

It is now an invariant that all source-level (non-synthetic)
functions have distinct names, and that all names include the
enclosing package.  Added test for this.

+ updated various clients.

LGTM=gri
R=gri
CC=golang-codereviews
https://golang.org/cl/122750043
2014-07-31 17:37:41 -04:00
Alan Donovan b5528ca070 go.tools/go/pointer: add test file missing from CL 112610043 (rev 32ae05502022)
TBR=gri
R=gri
CC=adg, golang-codereviews
https://golang.org/cl/111580043
2014-07-23 12:28:56 -04:00
Alan Donovan 79e0c7b71e go.tools/go/pointer: eliminate TODOs regarding sound treatment of unsafe.Pointer.
Ain't gonna happen.

Also, don't emit a warning when this happens.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/110030044
2014-07-08 10:11:36 -04:00
Alan Donovan 5c5c4f4888 go/pointer: fix crash: valueNode(*FreeVar) was allocating 1 node, even for multi-word types.
+ regression test.

Fixes golang/go#8172

Also: return error (not panic) when called with empty input.

LGTM=gri
R=crawshaw, gri
CC=golang-codereviews, jon
https://golang.org/cl/104270043
2014-06-19 15:30:51 -04:00
Alan Donovan 02dba5d1e6 go.tools/go/pointer: fix crash in constraint generation of ssa.Convert to a named unsafe.Pointer type.
+ test.

Fixes golang/go#8231.

LGTM=gri
R=gri
CC=golang-codereviews
https://golang.org/cl/106060046
2014-06-18 18:02:07 -04:00
Alan Donovan 9b38eafe60 go/pointer: implement pointer equivalence via hash-value numbering, a pre-solver optimization.
This reduces solver time by about 40%.
See hvn.go for detailed description.

Also in this CL:
- Update package docs.
- Added various global opt/debug options for maintainer convenience.
- Added logging of phase timing.
- Added stdlib_test, disabled by default, that runs the analysis
  on all tests in $GOROOT.
- include types when dumping solution

LGTM=crawshaw
R=crawshaw, dannyb
CC=golang-codereviews
https://golang.org/cl/96650048
2014-06-16 15:46:07 -04:00
Alan Donovan 38cb4c0966 go.tools/go/ssa: record ast.CallExpr.Rparen as Alloc.Pos() for varargs arrays.
+ pointer analysis test-case.

LGTM=gri
R=gri
CC=golang-codereviews
https://golang.org/cl/108980043
2014-06-13 17:12:28 -04:00
Alan Donovan fec252214b go.tools/ssa: create thunks for method expressions T.f.
Until now, the same Function was used to represent a method
(T)func() and the "method expression" function func(T) formed
from it. So the SSA code for this:

    var buf bytes.Buffer
    f := Buffer.Bytes
    f(buf)
    buf.Bytes()

would involve an implicit cast (ChangeType) on line 2.
However, compilers based on go/ssa may want to use different
calling conventions for them, like gccgo does (see issue
7839).  This change decouples them by using an anonymous
function called a "thunk", rather like this:

    f := func(r *bytes.Buffer) []byte { return r.Bytes() }

Thunks are similar to method wrappers; both are created by
makeWrapper.

"Interface method wrappers" were a special case of thunks for
direct calls (no indirection/fields) of interface methods.
They are now subsumed by thunks and have been deleted.  Now
that only the needed thunks are built, we don't need to
populate the concrete method sets of interface types at all,
so (*Program).Method and LookupMethod return nil for them.
This results in a slight reduction in function count (>1%) and
instruction count (<<1%).

Details:

go/ssa:
- API: ChangeType no longer supports func/method conversions.
- API: (*Program).FuncValue now returns nil for abstract
  (interface) methods.
- API: (*Function).RelString simplified.
  "$bound" is now a suffix not a prefix, and the receiver
  type is rendered package-relative.
- API: Function.Object is now defined for all wrappers too.
- API: (*Program).Method and LookupMethod return nil for
  abstract methods.
- emitConv no longer permits (non-identical)
  Signature->Signature conversions.  Added assertion.
- add and use isInterface helper
- sanity: we check packages after Build, not Create, otherwise
  cross-package refs might fail.

go/pointer:
- update tests for new function strings.
- pointer_test: don't add non-pointerlike probes to analysis.
  (The error was checked, but too late, causing a panic.)
- fixed a minor bug: if a test probe print(x) was the sole
  reference to x, no nodes were generated for x.
- (reflect.Type).MethodByName: updated due to ssa API changes.
  Also, fixed incorrect testdata/funcreflect.go expectation
  for MethodByName on interfaces.

oracle:
- fix for new FuncValue semantics.
- a "pointsto" query on an I.f thunk now returns an error.

Fixes golang/go#7839

LGTM=gri
R=gri
CC=golang-codereviews, pcc
https://golang.org/cl/93780044
2014-06-11 13:10:26 -04:00
Alan Donovan 43c97eab79 go.tools/go/pointer: fix solver nontermination bug due to reflective type construction cycles.
Programs such as this cause the PtrTo solver to attempt to
enumerate an infinite set of types {T, *T, ..., *******T, etc}.

        t := reflect.TypeOf(T{})
        for {
                t = reflect.PtrTo(t)
        }

The fix is to bound the depth of reflectively created types at
about 4 map/chan/slice/pointer constructors.

+ test.

LGTM=gri
R=gri
CC=crawshaw, golang-codereviews
https://golang.org/cl/102030044
2014-05-30 16:27:51 -04:00
Robert Griesemer 30b1abe2f7 go.tools: fix various typos
LGTM=adonovan
R=adonovan
CC=golang-codereviews
https://golang.org/cl/97920045
2014-05-02 14:38:08 -07:00
Alan Donovan d503a640d7 go.tools/go/ssa: name anon funcs by their enclosing func.
Before, they were named func@line:col which made them easy to find in the source if you know the file, but hard if you don't, and it made tests fragile.

Now, they are named outer$1, outer$2, etc, which makes them
more informative in a UI since "outer" has meaning.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/65630048
2014-02-28 10:18:55 -05:00
Alan Donovan 8c7a4539cd go.tools/pointer: implement (*reflect.rtype).MethodByName for abstract methods.
+ test.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/25810043
2014-02-12 12:45:55 -05:00
Alan Donovan 0dcaae1610 go.tools/go/loader: permit Create* methods to specify the ad-hoc package's path
CL 49530047 made the (over-)simplifying assumption that the
Path of an ad-hoc (Created) package should default to its
Name, i.e. package declaration.

With this change, the Name is still always computed from the
package declaration (by go/types) but the Path may be
specified by the loader.Config.  If "", the value of the Name
is used, which is not globally unique.

R=gri, axwalk
CC=golang-codereviews
https://golang.org/cl/55180043
2014-01-22 09:59:19 -05:00
Alan Donovan 3fc0fc1310 go.tools: rename packages.
Was:		Now:
ssa		go/ssa
importer	go/loader
pointer		go/pointer

Next CL: call -> go/callgraph (requires more care)

R=gri, crawshaw
CC=golang-codereviews
https://golang.org/cl/52960043
2014-01-16 09:33:58 -05:00