Commit Graph

87 Commits

Author SHA1 Message Date
Robert Griesemer 981e35990f go.tools/ssa/interp: fix init order test (partial build fix)
R=adonovan
TBR=adonovan
CC=golang-codereviews
https://golang.org/cl/52600044
2014-01-15 16:16:49 -08:00
Alan Donovan 8dabab4124 go.tools/ssa/interp: remove irrelevent parts of test, improve comments.
(Discovered during diagnosis of bug 7131.)

R=gri
CC=golang-codereviews
https://golang.org/cl/52780043
2014-01-15 13:50:11 -05:00
Alan Donovan 39fe7e6f8e go.tools/ssa/interp: fix windows build.
- Add missing import.
- platform-specific files syswrite() wrapper presents
  standard API to syscall.Write, even on Windows where
  first arg is a Handle.

Fixes golang/go#7100

R=gri, minux.ma, alex.brainman
CC=golang-codereviews
https://golang.org/cl/52250043
2014-01-14 21:47:31 -05:00
Alan Donovan f3eb05bcef go.tools/ssa: eliminate (non-nil) slice constants.
go/types no longer reports a constant value for a slice,
e.g. []byte("foo").

ssa.Const no longer support slice constants, only
bool/string/numeric and nil.

emitConv emits a Convert instruction for string->[]byte
conversions.

Added regression test for bug 6949.

R=gri
CC=golang-codereviews
https://golang.org/cl/50590043
2014-01-13 16:45:46 -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 5612f0615f go.tools/ssa: use correct word size for GOARCH during type checking, interpretation.
Also report an error for "cross-interpretation": not supported
due to the interpreter's assumption that host and target
{int,uint,uintptr} are the same.  (Too tedious and messy to fix.)

Tested manually:

% cat d.go
package main
const m = ^uintptr(0)
const w = m>>8&1 + m>>16&1 + m>>32&1
func main() { println(m, w) }

% ./ssadump -build=P -run d.go
package main:
  const m          m = 18446744073709551615:uintptr
  const w          w = 3:uintptr
18446744073709551615 3

% GOARCH=386 ./ssadump -build=P -run d.go
package main:
  const m          m = 4294967295:uintptr
  const w          w = 2:uintptr
Error: Cross-interpretation is not yet supported (target has GOARCH 386, interpreter has amd64).

Fixes golang/go#7080

R=gri
CC=golang-codereviews
https://golang.org/cl/49070043
2014-01-08 14:46:17 -05:00
Alan Donovan 8c66e887f7 go.tools/ssa: a blocking select's implicit "default" case should runtime-panic, not fall through.
Although such a control-flow path is impossible by
construction, we must avoid no-arg returns (even if
unreachable) in non-void functions.

Tested by adding a sanity-check that ssa.Return has the correct arity.
Also: added ssautil.Switches() test.

Fixes golang/go#7702

R=gri, axwalk
CC=golang-codereviews
https://golang.org/cl/46520043
2014-01-02 15:12:23 -05:00
Anthony Martin a1406b40c5 go.tools/ssa/interp: fix Plan 9 build for Brad
R=golang-codereviews, rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/26500043
2013-12-20 15:20:51 -08:00
Robert Griesemer 00fab17bd2 go.tools/ssa/interp: fix build (add missing runtime function)
Introduced by CL 41860043.

R=adonovan
TBR=adonovan
CC=golang-dev
https://golang.org/cl/42950044
2013-12-18 11:49:45 -08:00
Robert Griesemer 53dfbf8a00 go.tools: fix build
Missed a couple of places with previous CL.

R=adonovan
TBR=adonovan
CC=golang-dev
https://golang.org/cl/40850046
2013-12-17 16:21:23 -08:00
Alan Donovan 100638985b go.tools/ssa/interp: fix bug: recovered panic without NRPs should return zero values.
+ test.

R=gri
CC=golang-dev
https://golang.org/cl/38040043
2013-12-05 21:22:57 -05:00
Alan Donovan cf7368c879 go.tools/ssa: fix builder crash in select { case n, _ := <-c: ... }.
Cause: emitExtract requires a type for each component of the
receive tuple; blank supplies no such type.

Solution: remove type parameter for emitExtract as it is no
longer needed: since rev b75cc03b4a56 it is always identical
to the tuple.Type().At(index).

+ tests.

Fixes golang/go#6806.

R=gri, gri
CC=axwalk, golang-dev
https://golang.org/cl/30410043
2013-11-21 15:38:58 -05:00
Alan Donovan 19dd02b670 go.tools/ssa: fix bug in SSA lifting (!)
The previous code introduced spurious loop-carried
dependencies for variables local to a loop body (for example).
The SSA renaming pass now treats an Alloc instruction like a
Store of the zero value.

Also:
- added regression test
- improved log messages
- made the Store/Load/Alloc cases look more similar.

R=gri, gri
CC=golang-dev
https://golang.org/cl/26750043
2013-11-14 17:33:07 -05:00
Alan Donovan 75d66fbb7b go.tools/ssa/interp: fix build breakage.
(intersecting changes in client)

R=gri, gri
CC=golang-dev
https://golang.org/cl/24100046
2013-11-13 18:50:24 -05:00
Alan Donovan cadc2255fe go.tools/ssa: don't synthesize an empty "testmain" package.
Also, only examine functions defined in *_test.go files.

Added tests for empty and nonempty behaviour of CreateTestMainPackage.
(Required some surgery to interp_test.)

R=gri, gri
CC=golang-dev
https://golang.org/cl/25570044
2013-11-13 16:05:13 -05:00
Alan Donovan d84d338a42 go.tools/ssa/interp: improve print() on interfaces, and log message for panic.
R=gri
CC=golang-dev
https://golang.org/cl/21960043
2013-11-05 13:03:14 -05:00
Alan Donovan 74b761d099 go.tools/ssa: clarify spec of (*builder).complit().
Added test for []*map composite literals containing nested
literal subelements.  This required implementing
(reflect.Value).Map{Keys,Index} in ssa/interp.

Plus two minor fixes in ssa/interp.

R=gri
CC=golang-dev
https://golang.org/cl/20470043
2013-10-31 17:59:52 -04:00
Alan Donovan bac7098173 go.tools/ssa: fix crash on (new)(T) due to missing unparen() call.
Audited codebase for other occurrences, found two more.
Added test coverage for all of them.

R=gri
CC=golang-dev
https://golang.org/cl/14698043
2013-10-29 11:07:09 -04:00
Alan Donovan d644aa1fcd go.tools/ssa/interp: enable $GOROOT/test/switch.go test
(now that go/types can handle it)

R=gri
TBR=gri
CC=golang-dev
https://golang.org/cl/16970043
2013-10-24 22:38:10 -04:00
Alan Donovan 8636f40baf go.tools/ssa: CreateTestMainPackage: synthesize test driver as a package ("testmain") not 'main' function.
This allows us to run/analyze multiple tests.
Also it causes the production code packages to be properly initialized.

Also:
- cmd/ssadump: improved usage message (add example;
  incorporate LoadInitialPackages usage; explain how -run
  finds main).
- pointer, oracle, ssa/interp: use CreateTestMainPackage.
- ssa/builder.go: remove 'rundefers' instruction from package init,
  which no longer uses 'defer'.

R=gri
CC=golang-dev
https://golang.org/cl/15920047
2013-10-23 18:07:53 -04:00
Robert Griesemer c8f4d650c8 go.tools/ssa/interp: make typeAssert robust against nil types
R=adonovan
CC=golang-dev
https://golang.org/cl/16180043
2013-10-23 13:45:49 -07:00
Robert Griesemer a1886cc6ef go/tools/ssa/interp: make iface.eq robust against nil types
A future version of go/types.IsIdentical does not accept
nil types anymore.

R=adonovan
CC=golang-dev
https://golang.org/cl/16150043
2013-10-23 13:26:23 -07:00
Robert Griesemer d8391b87d1 go.tools/ssa/interp: use new Sizes interface (fix build)
R=adonovan
TBR=adonovan
CC=golang-dev
https://golang.org/cl/14722043
2013-10-15 15:30:03 -07:00
Alan Donovan 2accef29d7 go.tools/ssa: implement correct control flow for recovered panic.
A function such as this:
        func one() (x int) {
                defer func() { recover() }()
                x = 1
                panic("return")
        }
that combines named return parameters (NRPs) with deferred calls
that call recover, may return non-zero values despite the
fact it doesn't even contain a return statement. (!)

This requires a change to the SSA API: all functions'
control-flow graphs now have a second entry point, called
Recover, which is the block at which control flow resumes
after a recovered panic.  The Recover block simply loads the
NRPs and returns them.

As an optimization, most functions don't need a Recover block,
so it is omitted.  In fact it is only needed for functions that
have NRPs and defer a call to another function that _may_ call
recover.

Dataflow analysis of SSA now requires extra work, since every
may-panic instruction has an implicit control-flow edge to
the Recover block.  The only dataflow analysis so far implemented
is SSA renaming, for which we make the following simplifying
assumption: the Recover block only loads the NRPs and returns.
This means we don't really need to analyze it, we can just
skip the "lifting" of such NRPs.  We also special-case the Recover
block in the dominance computation.

Rejected alternative approaches:
- Specifying a Recover block for every defer instruction (like a
   traditional exception handler).
   This seemed like excessive generality, since Go programs
   only need the same degenerate form of Recover block.
- Adding an instruction to set the Recover block immediately
   after the named return values are set up, so that dominance
   can be computed without special-casing.
   This didn't seem worth the effort.

Interpreter:
- This CL completely reimplements the panic/recover/
  defer logic in the interpreter.  It's clearer and simpler
  and closer to the model in the spec.
- Some runtime panic messages have been changed to be closer
  to gc's, since tests depend on it.
- The interpreter now requires that the runtime.runtimeError
  type be part of the SSA program.  This requires that clients
  import this package prior to invoking the interpreter.
  This in turn requires (Importer).ImportPackage(path string),
  which this CL adds.
- All $GOROOT/test/recover{,1,2,3}.go tests are now passing.

NB, the bug described in coverage.go (defer/recover in a concatenated
init function) remains.  Will be fixed in a follow-up.

Fixes golang/go#6381

R=gri
CC=crawshaw, golang-dev
https://golang.org/cl/13844043
2013-10-14 15:38:56 -04:00
Alan Donovan 7aabe2e113 go.tools/ssa: build a separate Function for each init() func.
Before, we would concatenate all the init() blocks together,
resulting in incorrect treatment of a recovered panic in one
init block: the implicit return would cause the subsequent ones
to be skipped.

The result is simpler, and closer to what gc does.

The additional functions are visible in the call graph,
so some tests required updating.

R=gri
CC=crawshaw, golang-dev
https://golang.org/cl/14671044
2013-10-14 14:08:23 -04:00
Alan Donovan e1e9089196 go.tools/importer: change type of print{,ln} built-ins.
Before: func(any, ...interface{}).
After:  func(any, ...any)

They are no longer variadic, so you can't write print(x, y...).

(Recall that print(1) and print(interface{}(1)) behave
differently and that this is useful.)

Fixes bug 6560

R=gri
CC=golang-dev
https://golang.org/cl/14455054
2013-10-10 13:33:29 -04:00
Alan Donovan 9cce4759bb go.tools/importer: expose CreatePackage method.
The new method is functionally identical to typeCheck, and
obviates the LoadMainPackage method.

Updated all clients.

Fixes bug 6561.

R=gri
CC=golang-dev
https://golang.org/cl/14494051
2013-10-10 12:37:49 -04:00
Alan Donovan cd908f1108 go.tools/ssa/interp: capture stdout/err of target programs and check for "BUG".
The $GOROOT/tests may print "BUG" on failure but do not
necessarily exit zero, so we must capture their output too.

Details:
- make plan9 use unix's valueToBytes function (now in externals.go)
- direct the target's syscall.Write and print/println built-ins to a new utility, write().  This may capture the output into a global variable.

R=gri, r
CC=golang-dev
https://golang.org/cl/14550044
2013-10-08 14:35:39 -04:00
Alan Donovan 068f017092 go.tools/ssa: s/Ret/Return/g
R=gri
CC=golang-dev
https://golang.org/cl/14526044
2013-10-08 12:31:39 -04:00
Alan Donovan eb632ebaca go.tools/ssa/interp: enable tests of builtin(f()) where f has multiple results.
R=gri
CC=golang-dev
https://golang.org/cl/14408043
2013-10-04 16:52:12 -04:00
Alan Donovan 5db6491e90 go.tools/ssa/interp: fixes to equivalence relations.
- This change implements the correct type-based equivalence
  relation for aggregate types. e.g. comparison of struct
  types no longer compares the anonymous fields.  We do
  analogous things for hash().

- equals() and eqnil() have been separated: the former panics
  for uncomparable types, the latter permits comparisons of
  slice/map/func types against a literal nil and is intended
  for use only by "static" ssa.BinOp(EQL), not "dynamic" slice
  comparisons encountered during (e.g.) interface comparisons,
  which should panic regardless of operand nilness.

- we use a (global) typemap.Hasher to compute type hashes;
  hashing the Type.String() value was not sound.

+ tests.

NB, this change unearthed a bug in defer/recover within
init(); it will be fixed in a followup change.

R=gri, crawshaw
CC=golang-dev
https://golang.org/cl/13719043
2013-09-16 15:22:19 -04:00
Alan Donovan 4c5148c4cd go.tools/ssa/interp: set GOARCH to runtime.GOARCH in target program.
Causes $GOROOT/test/env.go to pass if GOARCH is unset in parent's env.

R=gri
CC=golang-dev
https://golang.org/cl/13709043
2013-09-16 09:27:59 -04:00
Robert Griesemer 1928c01286 go.tools/go/types: separate package descriptor from package object
Includes changes by adonovan to make oracle work again
(former CL 13395050).

R=adonovan
CC=golang-dev
https://golang.org/cl/13672044
2013-09-13 09:52:57 -07:00
Alan Donovan 7e7d99b4c9 go.tools/ssa/interp: fixes to enable running tests of package "encoding".
Running the interpreter on (most of) the tests package in
"encoding" unearthed a couple of ssa.builder bugs, already
fixed.  This CL contains the interpreter fixes that were
required.  (The "encoding" tests aren't added to the suite
since they're slow.)

Added intrinsics for:
        math.Exp
        math.Min
        hash/crc32.haveSSE42
        (reflect.Type).Field
        (reflect.Type).NumField
        (reflect.Type).NumMethod
        reflect.New
        (reflect.Value).NumMethod
        syscall.RawSyscall (returns ENOSYS)
        reflect.Set (a no-op)

Treat unsafe.Pointer -> *T conversions by returning new(T).
This is incorrect but at least preserves type-safety,
which is sufficient for these tests.

hashmap: treat nil *hashmap as an empty map.

R=gri
CC=golang-dev
https://golang.org/cl/12901046
2013-09-12 11:00:31 -04:00
Alan Donovan 6bc6da88ec go.tools/ssa/interp: implement unary negation of complex numbers.
Fixes golang/go#6291.

Also: call go/types.DefaultSizeof instead of hard-coding the
initial value of runtime.sizeof_C_MStats.

R=gri
CC=golang-dev
https://golang.org/cl/13648043
2013-09-10 12:08:55 -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 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 b43fa6fbda go.tools/cmd/ssadump: move ssa/ssadump.go command to its own package.
(Its former location was based on a misunderstanding of 'go build'.)

Also: set GOMAXPROCS to NumCPU by default.

R=crawshaw
CC=golang-dev
https://golang.org/cl/13354043
2013-08-29 21:34:36 -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
Alan Donovan c8a6890a12 go.tools/ssa: fix a bug building SSA code for ast.CompositeLit.
Map literals should use the same recursion logic as
struct/array/slice literals to apply an implicit &-operator to
the nested literals when a pointer is wanted.

+ test.

Also:
- ensure we set the source location for all Lookup and
  MapUpdate instructions.
- remove obsolete address.object field.

R=gri, crawshaw
CC=golang-dev
https://golang.org/cl/12787048
2013-08-22 10:13:51 -04:00
Alan Donovan 5cbf2abd36 go.tools/ssa: ensure address-deriving operations panic on nil inputs.
&x.f, &x[0], x[i:j], &*x all must panic if x==nil.

The first three are already addressed by the semantics of
FieldAddr, IndexAddr, Slice; updated docs to reflect this.
The final case requires generation of an additional dynamic check.

See golang.org/s/go12nil for details.

Tested on $GOROOT/test/nilptr2.go (with patch from CL 13108043)

Also: remove a TODO where a no-op will do.

R=gri, crawshaw
CC=golang-dev, rsc
https://golang.org/cl/13064044
2013-08-19 17:51:33 -04:00
Alan Donovan 7072253af5 go.tools/ssa: fixes, cleanups, cosmetic tweaks.
Fix bug: the Signature for an interface method wrapper
erroneously had a non-nil receiver.

Function:
- Set Pkg field non-nil even for wrappers.
  It is equal to that of the wrapped function.
  Only wrappers of error.Error
  (and its embeddings in other interfaces) may have nil.
  Sanity checker now asserts this.
- FullName() now uses .Synthetic field to discriminate
  synthetic methods, not Pkg==nil.
- Fullname() uses new relType() utility to print receiver type
  name unqualified if it belongs to the same package.
  (Alloc.String also uses relType utility.)

CallCommon:
- Description(): fix switch logic broken when we
  eliminated the Recv field.
- better docs.

R=david.crawshaw, crawshaw, gri
CC=golang-dev
https://golang.org/cl/13057043
2013-08-19 15:38:30 -04:00
Alan Donovan 50bd0e3288 go.tools/ssa: synthesize main functions for test packages.
Package.CreateTestMainFunction() creates a function called
main and adds it to the package.  This function calls
testing.Main in the Go library with the appropriate arguments:
slices of test, benchmark and example functions from the
package.

Tested by running the interpreter on the following tests:
- unicode/script_test.go
- unicode/digit_test.go
- hash/crc32/crc32_test.go
- path/path_test.go

It's also covered indirectly via the pointer analysis.

R=crawshaw, gri
CC=golang-dev
https://golang.org/cl/12814046
2013-08-19 15:00:25 -04:00
Alan Donovan 3b53279d8f go.tools/ssa: preserve type of &&/|| operands in result.
+ test.

With this change, the Go Oracle is now self-aware. :)

R=gri, rsc
CC=golang-dev
https://golang.org/cl/12381043
2013-08-19 12:50:40 -04:00
Robert Griesemer 0b3996b1d3 go.tools/ssa/interp: add missing "external" (fix build)
R=adonovan, bradfitz
CC=golang-dev
https://golang.org/cl/12898043
2013-08-13 15:00:07 -07:00
Robert Griesemer 875ff2496f go.tools/go/types: support for fake imports of package "C"
Also:
- cleaner method set printing
- disable debug mode internally (50% faster)

R=adonovan, bradfitz
CC=golang-dev
https://golang.org/cl/12578043
2013-08-07 14:09:50 -07:00
Robert Griesemer b956928b06 go.tools/go/types: Fix for broken IsAssignableTo.
Was broken by CL 12378043.

- factored out some error checking code
- adjusted error positions

R=adonovan
TBR=adonovan
CC=golang-dev
https://golang.org/cl/12401043
2013-08-05 13:54:22 -07:00
Robert Griesemer eae0511b70 go.tools/ssa/interp: fix build
fallthrough's are now checked - adjust
now illegal test.

TBR: adonovan

R=adonovan
CC=golang-dev
https://golang.org/cl/12041052
2013-07-30 20:28:18 -07:00
Alan Donovan 2f6855ad75 go.tools/ssa: avoid calling go/types.NewSelection, and eliminate it.
Also: s/LookupMethod/Method/

R=gri
CC=golang-dev
https://golang.org/cl/12058052
2013-07-30 16:36:58 -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