[dev.regabi] cmd/compile: simplify ir.Func somewhat

Two simplifications:

1. Statements (including ODCLFUNC) don't have types, and the
Func.Nname already has a type. There's no need for a second one.
However, there is a lot of code that expects to be able to call
Func.Type, so leave a forwarding method, like with Sym and Linksym.

2. Inline and remove ir.NewFuncNameAt. It doesn't really save any
code, and it's only used a handful of places.

Passes toolstash -cmp.

Change-Id: I51acaa341897dae0fcdf2fa576a10174a2ae4d1e
Reviewed-on: https://go-review.googlesource.com/c/go/+/280648
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>

4 files changed, 10 insertions, 13 deletions

diff --git a/src/cmd/compile/internal/typecheck/dcl.go b/src/cmd/compile/internal/typecheck/dcl.go
index 83f926e135..c4f32ff59d 100644
--- a/src/cmd/compile/internal/typecheck/dcl.go
+++ b/src/cmd/compile/internal/typecheck/dcl.go
@@ -23,7 +23,8 @@ func DeclFunc(sym *types.Sym, tfn ir.Ntype) *ir.Func {
 	}
 
 	fn := ir.NewFunc(base.Pos)
-	fn.Nname = ir.NewFuncNameAt(base.Pos, sym, fn)
+	fn.Nname = ir.NewNameAt(base.Pos, sym)
+	fn.Nname.Func = fn
 	fn.Nname.Defn = fn
 	fn.Nname.Ntype = tfn
 	ir.MarkFunc(fn.Nname)
diff --git a/src/cmd/compile/internal/typecheck/export.go b/src/cmd/compile/internal/typecheck/export.go
index 03deff8174..c525391401 100644
--- a/src/cmd/compile/internal/typecheck/export.go
+++ b/src/cmd/compile/internal/typecheck/export.go
@@ -31,12 +31,8 @@ func importconst(ipkg *types.Pkg, pos src.XPos, s *types.Sym, t *types.Type, val
 // ipkg is the package being imported
 func importfunc(ipkg *types.Pkg, pos src.XPos, s *types.Sym, t *types.Type) *ir.Name {
 	n := importobj(ipkg, pos, s, ir.ONAME, ir.PFUNC, t)
-
-	fn := ir.NewFunc(pos)
-	fn.SetType(t)
-	n.SetFunc(fn)
-	fn.Nname = n
-
+	n.Func = ir.NewFunc(pos)
+	n.Func.Nname = n
 	return n
 }
 
diff --git a/src/cmd/compile/internal/typecheck/func.go b/src/cmd/compile/internal/typecheck/func.go
index 9bb9245d4a..060024951e 100644
--- a/src/cmd/compile/internal/typecheck/func.go
+++ b/src/cmd/compile/internal/typecheck/func.go
@@ -409,7 +409,6 @@ func tcFunc(n *ir.Func) {
 	if t == nil {
 		return
 	}
-	n.SetType(t)
 	rcvr := t.Recv()
 	if rcvr != nil && n.Shortname != nil {
 		m := addmethod(n, n.Shortname, t, true, n.Pragma&ir.Nointerface != 0)
diff --git a/src/cmd/compile/internal/typecheck/iimport.go b/src/cmd/compile/internal/typecheck/iimport.go
index 86277e69bd..00ecd9b819 100644
--- a/src/cmd/compile/internal/typecheck/iimport.go
+++ b/src/cmd/compile/internal/typecheck/iimport.go
@@ -331,12 +331,13 @@ func (r *importReader) doDecl(sym *types.Sym) *ir.Name {
 			recv := r.param()
 			mtyp := r.signature(recv)
 
-			fn := ir.NewFunc(mpos)
-			fn.SetType(mtyp)
-			m := ir.NewFuncNameAt(mpos, ir.MethodSym(recv.Type, msym), fn)
-			m.SetType(mtyp)
-			m.Class_ = ir.PFUNC
 			// methodSym already marked m.Sym as a function.
+			m := ir.NewNameAt(mpos, ir.MethodSym(recv.Type, msym))
+			m.Class_ = ir.PFUNC
+			m.SetType(mtyp)
+
+			m.Func = ir.NewFunc(mpos)
+			m.Func.Nname = m
 
 			f := types.NewField(mpos, msym, mtyp)
 			f.Nname = m