From d10a90471275bf2d91c4c853d7d1f75f23a70a32 Mon Sep 17 00:00:00 2001 From: Dan Scales Date: Fri, 6 Aug 2021 16:29:09 -0700 Subject: [PATCH] [dev.typeparams] cmd/compile: don't export/import type parameter indices anymore types2 now determines type parameter indices lazily, so we don't need them just as we are importing. We set them in types1 as we are importing the type param list itself. type param indices are not strongly needed in types1 - we only use them in one place which could be rewritten. But I kept them in analogy to types2 (TypeParam.Index). Fixes #47451 Change-Id: I30631f95c45a259354eaf7ec5194f71e799eb358 Reviewed-on: https://go-review.googlesource.com/c/go/+/340532 Run-TryBot: Dan Scales TryBot-Result: Go Bot Reviewed-by: Robert Griesemer Trust: Dan Scales --- src/cmd/compile/internal/importer/iimport.go | 4 ---- src/cmd/compile/internal/typecheck/iexport.go | 1 - src/cmd/compile/internal/typecheck/iimport.go | 9 +++++++-- src/cmd/compile/internal/types/type.go | 6 ++++++ 4 files changed, 13 insertions(+), 7 deletions(-) diff --git a/src/cmd/compile/internal/importer/iimport.go b/src/cmd/compile/internal/importer/iimport.go index 523b00313d..99eb964415 100644 --- a/src/cmd/compile/internal/importer/iimport.go +++ b/src/cmd/compile/internal/importer/iimport.go @@ -364,10 +364,6 @@ func (r *importReader) obj(name string) { if r.p.exportVersion < iexportVersionGenerics { errorf("unexpected type param type") } - // Type parameter indices are lazily "allocated". - // There's no need to export them anymore. - // TODO change the export format accordingly - _ = int(r.int64()) name0, sub := parseSubscript(name) tn := types2.NewTypeName(pos, r.currPkg, name0, nil) t := (*types2.Checker)(nil).NewTypeParam(tn, nil) diff --git a/src/cmd/compile/internal/typecheck/iexport.go b/src/cmd/compile/internal/typecheck/iexport.go index d877b03e48..2944908bcb 100644 --- a/src/cmd/compile/internal/typecheck/iexport.go +++ b/src/cmd/compile/internal/typecheck/iexport.go @@ -531,7 +531,6 @@ func (p *iexporter) doDecl(n *ir.Name) { // A typeparam has a name, and has a type bound rather // than an underlying type. w.pos(n.Pos()) - w.int64(int64(n.Type().Index())) w.typ(n.Type().Bound()) break } diff --git a/src/cmd/compile/internal/typecheck/iimport.go b/src/cmd/compile/internal/typecheck/iimport.go index 2957212fb2..2e8b18c0b7 100644 --- a/src/cmd/compile/internal/typecheck/iimport.go +++ b/src/cmd/compile/internal/typecheck/iimport.go @@ -388,8 +388,9 @@ func (r *importReader) doDecl(sym *types.Sym) *ir.Name { // this types2-to-types1 translation. return sym.Def.(*ir.Name) } - index := int(r.int64()) - t := types.NewTypeParam(sym, index) + // The typeparam index is set at the point where the containing type + // param list is imported. + t := types.NewTypeParam(sym, 0) // Nname needed to save the pos. nname := ir.NewDeclNameAt(pos, ir.OTYPE, sym) sym.Def = nname @@ -875,6 +876,9 @@ func (r *importReader) typeList() []*types.Type { ts := make([]*types.Type, n) for i := range ts { ts[i] = r.typ() + if ts[i].IsTypeParam() { + ts[i].SetIndex(i) + } } return ts } @@ -887,6 +891,7 @@ func (r *importReader) tparamList() []*types.Field { fs := make([]*types.Field, n) for i := range fs { typ := r.typ() + typ.SetIndex(i) fs[i] = types.NewField(typ.Pos(), typ.Sym(), typ) } return fs diff --git a/src/cmd/compile/internal/types/type.go b/src/cmd/compile/internal/types/type.go index 1f01498ca1..099080f48f 100644 --- a/src/cmd/compile/internal/types/type.go +++ b/src/cmd/compile/internal/types/type.go @@ -1885,6 +1885,12 @@ func (t *Type) Index() int { return t.Extra.(*Typeparam).index } +// SetIndex sets the index of the type param within its param list. +func (t *Type) SetIndex(i int) { + t.wantEtype(TTYPEPARAM) + t.Extra.(*Typeparam).index = i +} + // SetBound sets the bound of a typeparam. func (t *Type) SetBound(bound *Type) { t.wantEtype(TTYPEPARAM)