Commit Graph

12 Commits

Author SHA1 Message Date
Alan Donovan e8afbfad8c go.tools/importer: API rethink.
The Importer type has been replaced with Config and Program.

Clients populate a Config, directly or more usually via
convenience functions.  They then call its Load() method to do
all of the typechecking and transitive-closure computation.

ssa.NewProgram and ssa.CreatePackages have been fused into
ssa.Create, which now cannot fail, since (*Config).Load()
reports all type errors.

Also:
- The addition of an ssa.GlobalDebug builder mode flag
  eliminates a loop-over-packages repeated in many clients.
- PackageInfo.Err flag unexported.  Clients never see bad infos now.
- cmd/ssadump: now only looks for func "main" in package "main".
- importsOf deleted, was dead code.

STILL TODO:
- ParseFile seems like API creep (though it's convenient)
  and CreateFromFiles is dangerous (w.r.t. FileSet identity).
  Need to think more...
- the need for clients to rely on elementwise correspondence
  of Config.CreatePkgs and Program.Created is a little sad.
- The command-line interface has not changed.
  That will happen in a follow-up.
  r recommends using a repeated flag: -package p -package q ...

R=gri
CC=axwalk, frederik.zipp, golang-codereviews
https://golang.org/cl/49530047
2014-01-15 21:37:55 -05:00
Alan Donovan d2fe54b33c go.tools/ssa: fix bug: lifting pass invalidated Referrers info for DebugRef's X operand.
Tested: by enabling debug info globally in stdlib_test,
the existing sanity checks catch it.

R=gri
CC=golang-codereviews
https://golang.org/cl/50570043
2014-01-10 17:10:12 -05:00
Alan Donovan 3d82e7e94a go.tools/ssa: fix crash in SSA builder when using GCImporter to satisfy imports (ssadump -build=G).
Packages were not being created for all types.Packages,
specifically, indirectly imported packages were missing.
(*Program).CreatePackages now iterates over the type-checker's
package map too.

Also: removed all concurrency from importer.  I think it was
incorrect (and hard to fix).

Also: change LoadInitialPackages so that all named packages
are loaded from source.  This happens regardless of whether
GCImporter is used to satisfy imports.

Details:
- importer.Config.SourceImports flag determines whether to
  load all packages from *.go source.
  (Before, this was indicated by Config.Build != nil.)
- importer.Config.Build field effectively defaults to
  &go/build.Default.  A zero importer.Config is now usable.
- importer.Importer.Config field is now exported.
- LoadPackage renamed to ImportPackage since the resulting
  packages may come from GCImporter (and be incomplete).
- doImport and ImportPackage fused.

Fixes golang/go#7028

R=gri, axwalk
CC=golang-codereviews
https://golang.org/cl/48770043
2014-01-09 14:11:54 -05:00
Alan Donovan d063887ea0 go.tools/ssa: move AllFunctions to ssautil subpackage
R=gri
CC=golang-dev
https://golang.org/cl/37970043
2013-12-05 17:16:00 -05:00
Alan Donovan 0faac9ebe6 go.tools/ssa: include line count in stdlib_test.
R=gri
CC=golang-dev
https://golang.org/cl/20860043
2013-11-01 14:32:44 -04:00
Alan Donovan 3f2f9a7e70 go.tools/importer: generalize command-line syntax.
Motivation: pointer analysis tools (like the oracle) want the
user to specify a set of initial packages, like 'go test'.
This change enables the user to specify a set of packages on
the command line using importer.LoadInitialPackages(args).

Each argument is interpreted as either:
- a comma-separated list of *.go source files together
  comprising one non-importable ad-hoc package.
  e.g. "src/pkg/net/http/triv.go" gives us [main].
- an import path, denoting both the imported package
  and its non-importable external test package, if any.
  e.g. "fmt" gives us [fmt, fmt_test].

Current type-checker limitations mean that only the first
import path may contribute tests: multiple packages augmented
by *_test.go files could create import cycles, which 'go test'
avoids by building a separate executable for each one.
That approach is less attractive for static analysis.

Details:  (many files touched, but importer.go is the crux)

importer:
- PackageInfo.Importable boolean indicates whether
  package is importable.
- un-expose Importer.Packages; expose AllPackages() instead.
- CreatePackageFromArgs has become LoadInitialPackages.
- imports() moved to util.go, renamed importsOf().
- InitialPackagesUsage usage message exported to clients.
- the package name for ad-hoc packages now comes from the
  'package' decl, not "main".

ssa.Program:
- added CreatePackages() method
- PackagesByPath un-exposed, renamed 'imported'.
- expose AllPackages and ImportedPackage accessors.

oracle:
- describe: explain and workaround a go/types bug.

Misc:
- Removed various unnecessary error.Error() calls in Printf args.

R=crawshaw
CC=golang-dev
https://golang.org/cl/13579043
2013-09-06 18:13:57 -04:00
Alan Donovan b21b4e8c88 go.tools/importer: negate "cgo" build tag to avoid native code in "net".
This removes the need for the caller to specify CGO_ENABLED=0
in the environment.

R=crawshaw
CC=golang-dev
https://golang.org/cl/13464045
2013-09-04 15:20:38 -04:00
Alan Donovan e2921e188a go.tools/importer: make loading/parsing concurrent.
1. ParseFiles (in util.go) parses each file in its own goroutine.

2. (*Importer).LoadPackage asynchronously prefetches the
   import graph by scanning the imports of each loaded package
   and calling LoadPackage on each one.

   LoadPackage is now thread-safe and idempotent: it uses a
   condition variable per package; the first goroutine to
   request a package becomes responsible for loading it and
   broadcasts to the others (waiting) when it becomes ready.

ssadump runs 34% faster when loading the oracle.

Also, refactorings:
- delete SourceLoader mechanism; just expose go/build.Context directly.
- CreateSourcePackage now also returns an error directly,
  rather than via PackageInfo.Err, since every client wants that.

R=crawshaw
CC=golang-dev
https://golang.org/cl/13509045
2013-09-04 13:15:49 -04:00
Alan Donovan 713699d8ad go.tools: add copyright messages to source files.
R=r
CC=golang-dev
https://golang.org/cl/13305043
2013-08-27 18:49:13 -04:00
Alex Brainman 4ff367ac3c go.tools/ssa: fix windows build
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12320043
2013-08-02 16:25:49 +10:00
Alan Donovan c28bf6e069 go.tools/ssa: extend debug information to arbitrary ast.Exprs.
CanonicalPos was inadequate since many pairs of instruction share the same pos (e.g. Allocs and Phis).  Instead, we generalize the DebugRef instruction to associate not just Idents but Exprs with ssa.Values.

We no longer store any DebugRefs for constant expressions, to save space.  (The type and value of such expressions can be obtained by other means, at a cost in complexity.)

Function.ValueForExpr queries the DebugRef info to return the ssa.Value of a given Expr.

Added tests.

Also:
- the DebugInfo flag is now per package, not global.
   It must be set between Create and Build phases if desired.
- {Value,Instruction}.Pos() documentation updated: we still maintain
  this information in the instruction stream even in non-debug mode,
  but we make fewer claims about its invariants.
- Go and Defer instructions can now use their respective go/defer
   token positions (not the call's lparen), so they do.
- SelectState:
     Posn token.Pos indicates the <- position
     DebugNode ast.Expr is the send stmt or receive expr.
- In building SelectStmt, we introduce extra temporaries in debug
   mode to hold the result of the receive in 'case <-ch' even though
   this value isn't ordinarily needed.
- Use *SelectState (indirectly) since the struct is getting bigger.
- Document some missing instructions in doc.go.

R=gri
CC=golang-dev
https://golang.org/cl/12147043
2013-07-31 13:13:05 -04:00
Alan Donovan 2a3a12930b go.tools/ssa: add test of SSA construction on $GOROOT/src/pkg/...
stdlib_test runs the builder (in sanity-checking mode) over
the Go standard library.  It also prints some stats about
the time and memory usage.

Also:
- importer.LoadPackage too (not just doImport) must consult
  the cache to avoid creating duplicate Package instances for
  the same import path when called serially from a test.
- importer: skip empty directories without an error.
- importer: print all errors, not just the first.
- visit.go: added AllFunctions utility for enumerating all
  Functions in a Program.
- ssa.MethodSet is not safe to expose from the package since
  it must be accessed under an (inaccessible) lock.  (!!!)
  This CL makes it unexported and restricts its use to the
  single function Program.LookupMethod().
- Program.MethodSet() has gone.
  Clients should instead iterate over the types.MethodSet
  and call LookupMethod.
- Package.DumpTo(): improved efficiency of methodset printing
  (by not creating wrappers) and accuracy (by showing * on
  receiver type only when necessary).
- Program.CreatePackage: documented precondition and added
  assertion.

R=gri
CC=golang-dev
https://golang.org/cl/12058048
2013-07-30 14:28:14 -04:00