Commit Graph

10 Commits

Author SHA1 Message Date
Andrew Gerrand 5ebbcd132f go.tools: use golang.org/x/... import paths
Rewrite performed with this command:
  sed -i '' 's_code.google.com/p/go\._golang.org/x/_g' \
    $(grep -lr 'code.google.com/p/go.' *)

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/170920043
2014-11-10 08:50:40 +11:00
Alan Donovan 067a2992ee go/pointer: fix runtime.startTimer intrinsic.
The test broke because the actual behaviour of time.startTimer changed in
https://golang.org/cl/129480043.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/131280043
2014-08-26 11:08:45 -04:00
Alan Donovan e5d15a9781 go.tools/go/pointer: add intrinsic for time.startTimer, which is implemented in C.
Without it, no value appears to be sent on NewTicker/NewTimer channels.

+ test

Also:
- add (callgraph.Edge).{Description,Pos} convenience methods
  to simplify client code when Site==nil.

LGTM=gri
R=gri, friestein68503
CC=golang-codereviews
https://golang.org/cl/112610043
2014-07-22 18:30:06 -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 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 74117bcfd8 go/pointer: use sparse bit vectors to represent points-to sets in solver.
This optimization reduces solve time (typically >90% of the
total) by about 78% when analysing real programs.  It also
makes the solver 100% deterministic since all iterations are
ordered.

Also:
- remove unnecessary nodeid parameter to solve() method.
- don't add a fieldInfo for singleton tuples (cosmetic fix).
- inline+simplify "worklist" type.
- replace "constraintset" type by a slice.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/95240043
2014-06-11 13:12:15 -04:00
Alan Donovan 98ed3d3c76 go.tools/go/pointer: node renumbering
This change renumbers nodes so that addressable ones
  (that may appear in a points-to set) all have lower
  numbers than non-addressable ones----initially at least:
  reflection, SetFinalizer, etc add new nodes during
  solving.

  This improves the efficiency of sparse PTS
  representations (to be added later).  The largest int in
  a PTS is now about 20% of the previous max.

  Overview:
  - move constraint stuff into constraint.go.
  - add two methods to constraint:
    (1) renumber(): renumbers all nodeids.  The
        implementations are very repetitive but simple.  I
        thought hard about other ways (mixins, reflection)
        but decided this one was fine.
	(2) indirect(): report the set of nodeids whose
        points-to relations depend on the solver, not just
        the initial constraint graph.
        (This method is currently unused and is logically
        part of a forthcoming change to implement PE/LE
        presolver optimizations. (Perhaps I should comment
        it out/remove it for now.)
  - split up the population of the intrinsics map by file.
  - delete analysis.probes (unused field)
  - remove state="..." from panic message; unnecessary.

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/73320043
2014-03-11 18:37:19 -04:00
Alan Donovan 829d52f2e8 go.tools/go/callgraph: simplifications to API.
1) We remove context sensitivity from API.  The pointer analysis is
   not sufficiently context-sensitive for the context information to
   be worth exposing.  (The actual analysis precision still benefits
   from being context-sensitive, though.)  Since all clients would
   discard the context info, we now do that for them.
2) Make the graph doubly-linked.  Edges are now shared by the Nodes
   at both ends of the edge so it's possible to navigate more easily
   (e.g. to the callers).
3) Graph and Node are now concrete, not interfaces.

Less code in every file!

LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/66460043
2014-02-20 11:57:48 -05:00
Alan Donovan 5f96644dbf go.tools/pointer: opt: type-based label tracking reduces solver time by up to 75%.
Observation: not all alias facts are interesting.
- A channel-peers query also cares about pointers of kind chan.
- An oracle "points-to" query on an expression of kind map
  only cares about maps.
- We always care about func, interface and reflect.Value,
  since they're needed for sound analysis of dynamic dispatch.

We needn't bother collecting alias information for
uninteresting pointers, and this massively reduces the number
of labels flowing in to the constraint system.
The only constraints that create new labels are addressOf
and offsetAddr; both are now selectively emitted by type.

We compute the set of type kinds to track, based on the
{Indirect,}Query types.  (We could enable tracking at an
even finer grain if we want.)

This requires that we can see all the {Indirect,}Query
value types a priori, which is not the case for the PrintCalls
mechanism used in the tests, so I have rewritten the latter
to use {Indirect,}Query instead.

This reduces the solver-phase time for the entire standard
library and tests from >8m to <2m.  Similar speedups are
obtained on small and medium-sized programs.

Details:
- shouldTrack inspects the flattened form of a type to see if
  it contains fields we must track.  It memoizes the result.
- added precondition checks to (*Config).Add{,Indirect}Query.
- added (*ssa.Program).LookupMethod convenience method.
- added Example of how to use the Query mechanism.
- removed code made dead by a recent invariant:
  the only pointerlike Const value is nil.
- don't generate constraints for any functions in "reflect".
  (we had forgotten to skip synthetic wrappers too).
- write PTA warnings to the log.
- add annotations for more intrinsics.

LGTM=gri, crawshaw
R=crawshaw, gri
CC=golang-codereviews
https://golang.org/cl/62540043
2014-02-18 12:40:44 -08:00
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