package noder
import (
+ "fmt"
"internal/pkgbits"
"io"
"runtime"
"cmd/compile/internal/base"
"cmd/compile/internal/inline"
"cmd/compile/internal/ir"
+ "cmd/compile/internal/pgo"
"cmd/compile/internal/typecheck"
"cmd/compile/internal/types"
"cmd/compile/internal/types2"
// later.
var localPkgReader *pkgReader
+// LookupMethodFunc returns the ir.Func for an arbitrary full symbol name if
+// that function exists in the set of available export data.
+//
+// This allows lookup of arbitrary functions and methods that aren't otherwise
+// referenced by the local package and thus haven't been read yet.
+//
+// TODO(prattmic): Does not handle instantiation of generic types. Currently
+// profiles don't contain the original type arguments, so we won't be able to
+// create the runtime dictionaries.
+//
+// TODO(prattmic): Hit rate of this function is usually fairly low, and errors
+// are only used when debug logging is enabled. Consider constructing cheaper
+// errors by default.
+func LookupFunc(fullName string) (*ir.Func, error) {
+ pkgPath, symName, err := ir.ParseLinkFuncName(fullName)
+ if err != nil {
+ return nil, fmt.Errorf("error parsing symbol name %q: %v", fullName, err)
+ }
+
+ pkg, ok := types.PkgMap()[pkgPath]
+ if !ok {
+ return nil, fmt.Errorf("pkg %s doesn't exist in %v", pkgPath, types.PkgMap())
+ }
+
+ // Symbol naming is ambiguous. We can't necessarily distinguish between
+ // a method and a closure. e.g., is foo.Bar.func1 a closure defined in
+ // function Bar, or a method on type Bar? Thus we must simply attempt
+ // to lookup both.
+
+ fn, err := lookupFunction(pkg, symName)
+ if err == nil {
+ return fn, nil
+ }
+
+ fn, mErr := lookupMethod(pkg, symName)
+ if mErr == nil {
+ return fn, nil
+ }
+
+ return nil, fmt.Errorf("%s is not a function (%v) or method (%v)", fullName, err, mErr)
+}
+
+func lookupFunction(pkg *types.Pkg, symName string) (*ir.Func, error) {
+ sym := pkg.Lookup(symName)
+
+ // TODO(prattmic): Enclosed functions (e.g., foo.Bar.func1) are not
+ // present in objReader, only as OCLOSURE nodes in the enclosing
+ // function.
+ pri, ok := objReader[sym]
+ if !ok {
+ return nil, fmt.Errorf("func sym %v missing objReader", sym)
+ }
+
+ name := pri.pr.objIdx(pri.idx, nil, nil, false).(*ir.Name)
+ if name.Op() != ir.ONAME || name.Class != ir.PFUNC {
+ return nil, fmt.Errorf("func sym %v refers to non-function name: %v", sym, name)
+ }
+ return name.Func, nil
+}
+
+func lookupMethod(pkg *types.Pkg, symName string) (*ir.Func, error) {
+ // N.B. readPackage creates a Sym for every object in the package to
+ // initialize objReader and importBodyReader, even if the object isn't
+ // read.
+ //
+ // However, objReader is only initialized for top-level objects, so we
+ // must first lookup the type and use that to find the method rather
+ // than looking for the method directly.
+ typ, meth, err := ir.LookupMethodSelector(pkg, symName)
+ if err != nil {
+ return nil, fmt.Errorf("error looking up method symbol %q: %v", symName, err)
+ }
+
+ pri, ok := objReader[typ]
+ if !ok {
+ return nil, fmt.Errorf("type sym %v missing objReader", typ)
+ }
+
+ name := pri.pr.objIdx(pri.idx, nil, nil, false).(*ir.Name)
+ if name.Op() != ir.OTYPE {
+ return nil, fmt.Errorf("type sym %v refers to non-type name: %v", typ, name)
+ }
+ if name.Alias() {
+ return nil, fmt.Errorf("type sym %v refers to alias", typ)
+ }
+
+ for _, m := range name.Type().Methods() {
+ if m.Sym == meth {
+ fn := m.Nname.(*ir.Name).Func
+ return fn, nil
+ }
+ }
+
+ return nil, fmt.Errorf("method %s missing from method set of %v", symName, typ)
+}
+
// unified constructs the local package's Internal Representation (IR)
// from its syntax tree (AST).
//
func unified(m posMap, noders []*noder) {
inline.InlineCall = unifiedInlineCall
typecheck.HaveInlineBody = unifiedHaveInlineBody
+ pgo.LookupFunc = LookupFunc
data := writePkgStub(m, noders)