[dev.typeparams] cmd/compile: cleanup unified IR file format a little

This CL makes two changes:

1. It moves object symbols and code tags into a new "relocName"
relocation, which should eventually allow getting rid of objStub.

2. It moves the type parameter data into the relocObjDict relocation,
so everything related to writing out dictionaries is contained there.

Change-Id: If0f7ff7d9384e8664957c3180bf6f20e97bcff6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/336051
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>

1 files changed, 42 insertions, 37 deletions

diff --git a/src/cmd/compile/internal/noder/reader.go b/src/cmd/compile/internal/noder/reader.go
index de708769ba..44d1c4f28b 100644
--- a/src/cmd/compile/internal/noder/reader.go
+++ b/src/cmd/compile/internal/noder/reader.go
@@ -534,18 +534,10 @@ func (r *reader) obj() ir.Node {
 }
 
 func (pr *pkgReader) objIdx(idx int, implicits, explicits []*types.Type) ir.Node {
-	r := pr.newReader(relocObj, idx, syncObject1)
-	r.ext = pr.newReader(relocObjExt, idx, syncObject1)
-
-	_, sym := r.qualifiedIdent()
-
-	dict := &readerDict{}
-	r.dict = dict
-	r.ext.dict = dict
-
-	r.typeParamBounds(sym, implicits, explicits)
+	rname := pr.newReader(relocName, idx, syncObject1)
+	_, sym := rname.qualifiedIdent()
+	tag := codeObj(rname.code(syncCodeObj))
 
-	tag := codeObj(r.code(syncCodeObj))
 	if tag == objStub {
 		assert(!sym.IsBlank())
 		switch sym.Pkg {
@@ -556,30 +548,19 @@ func (pr *pkgReader) objIdx(idx int, implicits, explicits []*types.Type) ir.Node
 			return pri.pr.objIdx(pri.idx, nil, explicits)
 		}
 		if haveLegacyImports {
-			assert(!r.hasTypeParams())
+			assert(len(explicits) == 0)
 			return typecheck.Resolve(ir.NewIdent(src.NoXPos, sym))
 		}
 		base.Fatalf("unresolved stub: %v", sym)
 	}
 
-	{
-		rdict := pr.newReader(relocObjDict, idx, syncObject1)
-		r.dict.derived = make([]derivedInfo, rdict.len())
-		r.dict.derivedTypes = make([]*types.Type, len(r.dict.derived))
-		for i := range r.dict.derived {
-			r.dict.derived[i] = derivedInfo{rdict.reloc(relocType), rdict.bool()}
-		}
-		r.dict.funcs = make([]objInfo, rdict.len())
-		r.dict.funcsObj = make([]ir.Node, len(r.dict.funcs))
-		for i := range r.dict.funcs {
-			objIdx := rdict.reloc(relocObj)
-			targs := make([]typeInfo, rdict.len())
-			for j := range targs {
-				targs[j] = rdict.typInfo()
-			}
-			r.dict.funcs[i] = objInfo{idx: objIdx, explicits: targs}
-		}
-	}
+	dict := pr.objDictIdx(sym, idx, implicits, explicits)
+
+	r := pr.newReader(relocObj, idx, syncObject1)
+	r.ext = pr.newReader(relocObjExt, idx, syncObject1)
+
+	r.dict = dict
+	r.ext.dict = dict
 
 	sym = r.mangle(sym)
 	if !sym.IsBlank() && sym.Def != nil {
@@ -692,8 +673,10 @@ func (r *reader) mangle(sym *types.Sym) *types.Sym {
 	return sym.Pkg.Lookup(buf.String())
 }
 
-func (r *reader) typeParamBounds(sym *types.Sym, implicits, explicits []*types.Type) {
-	r.sync(syncTypeParamBounds)
+func (pr *pkgReader) objDictIdx(sym *types.Sym, idx int, implicits, explicits []*types.Type) *readerDict {
+	r := pr.newReader(relocObjDict, idx, syncObject1)
+
+	var dict readerDict
 
 	nimplicits := r.len()
 	nexplicits := r.len()
@@ -702,12 +685,11 @@ func (r *reader) typeParamBounds(sym *types.Sym, implicits, explicits []*types.T
 		base.Fatalf("%v has %v+%v params, but instantiated with %v+%v args", sym, nimplicits, nexplicits, len(implicits), len(explicits))
 	}
 
-	r.dict.targs = append(implicits[:nimplicits:nimplicits], explicits...)
-	r.dict.implicits = nimplicits
+	dict.targs = append(implicits[:nimplicits:nimplicits], explicits...)
+	dict.implicits = nimplicits
 
 	// For stenciling, we can just skip over the type parameters.
-
-	for range r.dict.targs[r.dict.implicits:] {
+	for range dict.targs[dict.implicits:] {
 		// Skip past bounds without actually evaluating them.
 		r.sync(syncType)
 		if r.bool() {
@@ -716,6 +698,25 @@ func (r *reader) typeParamBounds(sym *types.Sym, implicits, explicits []*types.T
 			r.reloc(relocType)
 		}
 	}
+
+	dict.derived = make([]derivedInfo, r.len())
+	dict.derivedTypes = make([]*types.Type, len(dict.derived))
+	for i := range dict.derived {
+		dict.derived[i] = derivedInfo{r.reloc(relocType), r.bool()}
+	}
+
+	dict.funcs = make([]objInfo, r.len())
+	dict.funcsObj = make([]ir.Node, len(dict.funcs))
+	for i := range dict.funcs {
+		objIdx := r.reloc(relocObj)
+		targs := make([]typeInfo, r.len())
+		for j := range targs {
+			targs[j] = r.typInfo()
+		}
+		dict.funcs[i] = objInfo{idx: objIdx, explicits: targs}
+	}
+
+	return &dict
 }
 
 func (r *reader) typeParamNames() {
@@ -790,7 +791,11 @@ func (r *reader) selector() (origPkg *types.Pkg, sym *types.Sym) {
 }
 
 func (r *reader) hasTypeParams() bool {
-	return r.dict != nil && len(r.dict.targs) != 0
+	return r.dict.hasTypeParams()
+}
+
+func (dict *readerDict) hasTypeParams() bool {
+	return dict != nil && len(dict.targs) != 0
 }
 
 // @@@ Compiler extensions