diff options
Diffstat (limited to 'src/cmd/compile/internal/reflectdata/reflect.go')
| -rw-r--r-- | src/cmd/compile/internal/reflectdata/reflect.go | 64 |
1 files changed, 52 insertions, 12 deletions
diff --git a/src/cmd/compile/internal/reflectdata/reflect.go b/src/cmd/compile/internal/reflectdata/reflect.go index 06c4986cf4..01eaf26a0a 100644 --- a/src/cmd/compile/internal/reflectdata/reflect.go +++ b/src/cmd/compile/internal/reflectdata/reflect.go @@ -52,6 +52,9 @@ var ( signatset = make(map[*types.Type]struct{}) signatslice []*types.Type + gcsymmu sync.Mutex // protects gcsymset and gcsymslice + gcsymset = make(map[*types.Type]struct{}) + itabs []itabEntry ptabs []*ir.Name ) @@ -694,7 +697,8 @@ func dcommontype(lsym *obj.LSym, t *types.Type) int { sptr = writeType(tptr) } - gcsym, useGCProg, ptrdata := dgcsym(t) + gcsym, useGCProg, ptrdata := dgcsym(t, true) + delete(gcsymset, t) // ../../../../reflect/type.go:/^type.rtype // actual type structure @@ -1321,6 +1325,16 @@ func WriteRuntimeTypes() { } } } + + // Emit GC data symbols. + gcsyms := make([]typeAndStr, 0, len(gcsymset)) + for t := range gcsymset { + gcsyms = append(gcsyms, typeAndStr{t: t, short: types.TypeSymName(t), regular: t.String()}) + } + sort.Sort(typesByString(gcsyms)) + for _, ts := range gcsyms { + dgcsym(ts.t, true) + } } func WriteTabs() { @@ -1490,29 +1504,46 @@ func (a typesByString) Swap(i, j int) { a[i], a[j] = a[j], a[i] } // const maxPtrmaskBytes = 2048 -// dgcsym emits and returns a data symbol containing GC information for type t, -// along with a boolean reporting whether the UseGCProg bit should be set in -// the type kind, and the ptrdata field to record in the reflect type information. -func dgcsym(t *types.Type) (lsym *obj.LSym, useGCProg bool, ptrdata int64) { +// GCSym returns a data symbol containing GC information for type t, along +// with a boolean reporting whether the UseGCProg bit should be set in the +// type kind, and the ptrdata field to record in the reflect type information. +// GCSym may be called in concurrent backend, so it does not emit the symbol +// content. +func GCSym(t *types.Type) (lsym *obj.LSym, useGCProg bool, ptrdata int64) { + // Record that we need to emit the GC symbol. + gcsymmu.Lock() + if _, ok := gcsymset[t]; !ok { + gcsymset[t] = struct{}{} + } + gcsymmu.Unlock() + + return dgcsym(t, false) +} + +// dgcsym returns a data symbol containing GC information for type t, along +// with a boolean reporting whether the UseGCProg bit should be set in the +// type kind, and the ptrdata field to record in the reflect type information. +// When write is true, it writes the symbol data. +func dgcsym(t *types.Type, write bool) (lsym *obj.LSym, useGCProg bool, ptrdata int64) { ptrdata = types.PtrDataSize(t) if ptrdata/int64(types.PtrSize) <= maxPtrmaskBytes*8 { - lsym = dgcptrmask(t) + lsym = dgcptrmask(t, write) return } useGCProg = true - lsym, ptrdata = dgcprog(t) + lsym, ptrdata = dgcprog(t, write) return } // dgcptrmask emits and returns the symbol containing a pointer mask for type t. -func dgcptrmask(t *types.Type) *obj.LSym { +func dgcptrmask(t *types.Type, write bool) *obj.LSym { ptrmask := make([]byte, (types.PtrDataSize(t)/int64(types.PtrSize)+7)/8) fillptrmask(t, ptrmask) p := fmt.Sprintf("runtime.gcbits.%x", ptrmask) lsym := base.Ctxt.Lookup(p) - if !lsym.OnList() { + if write && !lsym.OnList() { for i, x := range ptrmask { objw.Uint8(lsym, i, x) } @@ -1549,14 +1580,14 @@ func fillptrmask(t *types.Type, ptrmask []byte) { // [types.PtrDataSize(t), t.Width]). // In practice, the size is types.PtrDataSize(t) except for non-trivial arrays. // For non-trivial arrays, the program describes the full t.Width size. -func dgcprog(t *types.Type) (*obj.LSym, int64) { +func dgcprog(t *types.Type, write bool) (*obj.LSym, int64) { types.CalcSize(t) if t.Width == types.BADWIDTH { base.Fatalf("dgcprog: %v badwidth", t) } lsym := TypeLinksymPrefix(".gcprog", t) var p gcProg - p.init(lsym) + p.init(lsym, write) p.emit(t, 0) offset := p.w.BitIndex() * int64(types.PtrSize) p.end() @@ -1570,11 +1601,17 @@ type gcProg struct { lsym *obj.LSym symoff int w gcprog.Writer + write bool } -func (p *gcProg) init(lsym *obj.LSym) { +func (p *gcProg) init(lsym *obj.LSym, write bool) { p.lsym = lsym + p.write = write && !lsym.OnList() p.symoff = 4 // first 4 bytes hold program length + if !write { + p.w.Init(func(byte) {}) + return + } p.w.Init(p.writeByte) if base.Debug.GCProg > 0 { fmt.Fprintf(os.Stderr, "compile: start GCProg for %v\n", lsym) @@ -1588,6 +1625,9 @@ func (p *gcProg) writeByte(x byte) { func (p *gcProg) end() { p.w.End() + if !p.write { + return + } objw.Uint32(p.lsym, 0, uint32(p.symoff-4)) objw.Global(p.lsym, int32(p.symoff), obj.DUPOK|obj.RODATA|obj.LOCAL) p.lsym.Set(obj.AttrContentAddressable, true) |