diff options
Diffstat (limited to 'src/cmd/compile/internal/typecheck/subr.go')
| -rw-r--r-- | src/cmd/compile/internal/typecheck/subr.go | 67 |
1 files changed, 43 insertions, 24 deletions
diff --git a/src/cmd/compile/internal/typecheck/subr.go b/src/cmd/compile/internal/typecheck/subr.go index 34f20879f1..d4af4e172e 100644 --- a/src/cmd/compile/internal/typecheck/subr.go +++ b/src/cmd/compile/internal/typecheck/subr.go @@ -352,7 +352,10 @@ func Assignop(src, dst *types.Type) (ir.Op, string) { if types.Identical(src, dst) { return ir.OCONVNOP, "" } + return Assignop1(src, dst) +} +func Assignop1(src, dst *types.Type) (ir.Op, string) { // 2. src and dst have identical underlying types and // a. either src or dst is not a named type, or // b. both are empty interface types, or @@ -1019,10 +1022,11 @@ type Tsubster struct { SubstForwFunc func(*types.Type) *types.Type } -// Typ computes the type obtained by substituting any type parameter in t with the -// corresponding type argument in subst. If t contains no type parameters, the -// result is t; otherwise the result is a new type. It deals with recursive types -// by using TFORW types and finding partially or fully created types via sym.Def. +// Typ computes the type obtained by substituting any type parameter or shape in t +// that appears in subst.Tparams with the corresponding type argument in subst.Targs. +// If t contains no type parameters, the result is t; otherwise the result is a new +// type. It deals with recursive types by using TFORW types and finding partially or +// fully created types via sym.Def. func (ts *Tsubster) Typ(t *types.Type) *types.Type { // Defer the CheckSize calls until we have fully-defined // (possibly-recursive) top-level type. @@ -1033,14 +1037,14 @@ func (ts *Tsubster) Typ(t *types.Type) *types.Type { } func (ts *Tsubster) typ1(t *types.Type) *types.Type { - if !t.HasTParam() && t.Kind() != types.TFUNC { + if !t.HasTParam() && !t.HasShape() && t.Kind() != types.TFUNC { // Note: function types need to be copied regardless, as the // types of closures may contain declarations that need // to be copied. See #45738. return t } - if t.IsTypeParam() { + if t.IsTypeParam() || t.IsShape() { for i, tp := range ts.Tparams { if tp == t { return ts.Targs[i] @@ -1072,14 +1076,14 @@ func (ts *Tsubster) typ1(t *types.Type) *types.Type { var targsChanged bool var forw *types.Type - if t.Sym() != nil && t.HasTParam() { + if t.Sym() != nil && (t.HasTParam() || t.HasShape()) { // Need to test for t.HasTParam() again because of special TFUNC case above. // Translate the type params for this type according to // the tparam/targs mapping from subst. neededTargs = make([]*types.Type, len(t.RParams())) for i, rparam := range t.RParams() { neededTargs[i] = ts.typ1(rparam) - if !types.Identical(neededTargs[i], rparam) { + if !types.IdenticalStrict(neededTargs[i], rparam) { targsChanged = true } } @@ -1286,7 +1290,7 @@ func (ts *Tsubster) typ1(t *types.Type) *types.Type { // fields, set force to true. func (ts *Tsubster) tstruct(t *types.Type, force bool) *types.Type { if t.NumFields() == 0 { - if t.HasTParam() { + if t.HasTParam() || t.HasShape() { // For an empty struct, we need to return a new type, // since it may now be fully instantiated (HasTParam // becomes false). @@ -1312,6 +1316,7 @@ func (ts *Tsubster) tstruct(t *types.Type, force bool) *types.Type { // the type param, not the instantiated type). newfields[i] = types.NewField(f.Pos, f.Sym, t2) newfields[i].Embedded = f.Embedded + newfields[i].Note = f.Note if f.IsDDD() { newfields[i].SetIsDDD(true) } @@ -1387,19 +1392,20 @@ func genericTypeName(sym *types.Sym) string { return sym.Name[0:strings.Index(sym.Name, "[")] } -// Shapify takes a concrete type and returns a GCshape type that can +// Shapify takes a concrete type and a type param index, and returns a GCshape type that can // be used in place of the input type and still generate identical code. // No methods are added - all methods calls directly on a shape should // be done by converting to an interface using the dictionary. // -// TODO: this could take the generic function and base its decisions -// on how that generic function uses this type argument. For instance, -// if it doesn't use it as a function argument/return value, then -// we don't need to distinguish int64 and float64 (because they only -// differ in how they get passed as arguments). For now, we only -// unify two different types if they are identical in every possible way. -func Shapify(t *types.Type) *types.Type { - assert(!t.HasShape()) +// For now, we only consider two types to have the same shape, if they have exactly +// the same underlying type or they are both pointer types. +// +// Shape types are also distinguished by the index of the type in a type param/arg +// list. We need to do this so we can distinguish and substitute properly for two +// type params in the same function that have the same shape for a particular +// instantiation. +func Shapify(t *types.Type, index int) *types.Type { + assert(!t.IsShape()) // Map all types with the same underlying type to the same shape. u := t.Underlying() @@ -1409,22 +1415,35 @@ func Shapify(t *types.Type) *types.Type { u = types.Types[types.TUINT8].PtrTo() } - if s := shaped[u]; s != nil { + if shapeMap == nil { + shapeMap = map[int]map[*types.Type]*types.Type{} + } + submap := shapeMap[index] + if submap == nil { + submap = map[*types.Type]*types.Type{} + shapeMap[index] = submap + } + if s := submap[u]; s != nil { return s } - sym := shapePkg.Lookup(u.LinkString()) + nm := fmt.Sprintf("%s_%d", u.LinkString(), index) + sym := types.ShapePkg.Lookup(nm) + if sym.Def != nil { + // Use any existing type with the same name + submap[u] = sym.Def.Type() + return submap[u] + } name := ir.NewDeclNameAt(u.Pos(), ir.OTYPE, sym) s := types.NewNamed(name) + sym.Def = name s.SetUnderlying(u) s.SetIsShape(true) s.SetHasShape(true) name.SetType(s) name.SetTypecheck(1) - shaped[u] = s + submap[u] = s return s } -var shaped = map[*types.Type]*types.Type{} - -var shapePkg = types.NewPkg(".shape", ".shape") +var shapeMap map[int]map[*types.Type]*types.Type |