mirror of
https://github.com/golang/go
synced 2024-10-01 11:18:32 -06:00
f119874203
Command set: - what: an extremely fast query that parses a single file and returns the AST stack, package name and the set of query modes that apply to the current selection. Intended for GUI tools that need to grey out UI elements. - definition: shows the definition of an identifier. - pointsto: the PTA features of 'describe' have been split out into their own command. - describe: with PTA stripped out, the cost is now bounded by type checking. Performance: - The importer.Config.TypeCheckFuncBodies predicate supports setting the 'IgnoreFuncBodies' typechecker flag on a per-package basis. This means we can load dependencies from source more quickly if we only need exported types. (We avoid gcimport data because it may be absent or stale.) This also means we can run type-based queries on packages that aren't part of the pointer analysis scope. (Yay.) - Modes that require only type analysis of the query package run a "what" query first, and restrict their analysis scope to just that package and its dependencies (sans func bodies), making them much faster. - We call newOracle not oracle.New in Query, so that the 'needs' bitset isn't ignored (oops!). This makes the non-PTA queries faster. Also: - removed vestigial timers junk. - pos.go: existing position utilties split out into own file. Added parsePosFlag utility. - numerous cosmetic tweaks. + very basic tests. To do in follow-ups: - sophisticated editor integration of "what". - better tests. - refactoring of control flow as described in comment. - changes to "implements", "describe" commands. - update design doc + user manual. R=crawshaw, dominik.honnef CC=golang-dev, gri https://golang.org/cl/40630043
96 lines
2.7 KiB
Go
96 lines
2.7 KiB
Go
// Copyright 2013 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package oracle
|
|
|
|
import (
|
|
"fmt"
|
|
"go/token"
|
|
|
|
"code.google.com/p/go.tools/call"
|
|
"code.google.com/p/go.tools/oracle/serial"
|
|
"code.google.com/p/go.tools/ssa"
|
|
)
|
|
|
|
// Callstack displays an arbitrary path from a root of the callgraph
|
|
// to the function at the current position.
|
|
//
|
|
// The information may be misleading in a context-insensitive
|
|
// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
|
|
// calls Z when it is called from X. TODO(adonovan): think about UI.
|
|
//
|
|
// TODO(adonovan): permit user to specify a starting point other than
|
|
// the analysis root.
|
|
//
|
|
func callstack(o *Oracle, qpos *QueryPos) (queryResult, error) {
|
|
pkg := o.prog.Package(qpos.info.Pkg)
|
|
if pkg == nil {
|
|
return nil, fmt.Errorf("no SSA package")
|
|
}
|
|
|
|
if !ssa.HasEnclosingFunction(pkg, qpos.path) {
|
|
return nil, fmt.Errorf("this position is not inside a function")
|
|
}
|
|
|
|
buildSSA(o)
|
|
|
|
target := ssa.EnclosingFunction(pkg, qpos.path)
|
|
if target == nil {
|
|
return nil, fmt.Errorf("no SSA function built for this location (dead code?)")
|
|
}
|
|
|
|
// Run the pointer analysis and build the complete call graph.
|
|
o.ptaConfig.BuildCallGraph = true
|
|
callgraph := ptrAnalysis(o).CallGraph
|
|
|
|
// Search for an arbitrary path from a root to the target function.
|
|
isEnd := func(n call.GraphNode) bool { return n.Func() == target }
|
|
callpath := call.PathSearch(callgraph.Root(), isEnd)
|
|
if callpath != nil {
|
|
callpath = callpath[1:] // remove synthetic edge from <root>
|
|
}
|
|
|
|
return &callstackResult{
|
|
qpos: qpos,
|
|
target: target,
|
|
callpath: callpath,
|
|
}, nil
|
|
}
|
|
|
|
type callstackResult struct {
|
|
qpos *QueryPos
|
|
target *ssa.Function
|
|
callpath []call.Edge
|
|
}
|
|
|
|
func (r *callstackResult) display(printf printfFunc) {
|
|
if r.callpath != nil {
|
|
printf(r.qpos, "Found a call path from root to %s", r.target)
|
|
printf(r.target, "%s", r.target)
|
|
for i := len(r.callpath) - 1; i >= 0; i-- {
|
|
edge := r.callpath[i]
|
|
printf(edge.Site, "%s from %s", edge.Site.Common().Description(), edge.Caller.Func())
|
|
}
|
|
} else {
|
|
printf(r.target, "%s is unreachable in this analysis scope", r.target)
|
|
}
|
|
}
|
|
|
|
func (r *callstackResult) toSerial(res *serial.Result, fset *token.FileSet) {
|
|
var callers []serial.Caller
|
|
for i := len(r.callpath) - 1; i >= 0; i-- { // (innermost first)
|
|
edge := r.callpath[i]
|
|
callers = append(callers, serial.Caller{
|
|
Pos: fset.Position(edge.Site.Pos()).String(),
|
|
Caller: edge.Caller.Func().String(),
|
|
Desc: edge.Site.Common().Description(),
|
|
})
|
|
}
|
|
res.Callstack = &serial.CallStack{
|
|
Pos: fset.Position(r.target.Pos()).String(),
|
|
Target: r.target.String(),
|
|
Callers: callers,
|
|
}
|
|
}
|