[dev.typeparams] cmd/compile: remove ir.CallUse

Unneeded after the previous CL changed inlining to leave OINLCALL
nodes in place.

Change-Id: I9af09a86a21caa51a1117b3de17d7312dd702600
Reviewed-on: https://go-review.googlesource.com/c/go/+/332650
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Trust: Matthew Dempsky <mdempsky@google.com>

src/cmd/compile/internal/ir/expr.go

@@ -142,17 +142,6 @@ func (n *BinaryExpr) SetOp(op Op) {
 	}
 }
 
-// A CallUse records how the result of the call is used:
-type CallUse byte
-
-const (
-	_ CallUse = iota
-
-	CallUseExpr // single expression result is used
-	CallUseList // list of results are used
-	CallUseStmt // results not used - call is a statement
-)
-
 // A CallExpr is a function call X(Args).
 type CallExpr struct {
 	miniExpr
@@ -161,7 +150,6 @@ type CallExpr struct {
 	Args      Nodes
 	KeepAlive []*Name // vars to be kept alive until call returns
 	IsDDD     bool
-	Use       CallUse
 	NoInline  bool
 }
 

src/cmd/compile/internal/noder/helpers.go

@@ -113,9 +113,6 @@ func Binary(pos src.XPos, op ir.Op, typ *types.Type, x, y ir.Node) ir.Node {
 func Call(pos src.XPos, typ *types.Type, fun ir.Node, args []ir.Node, dots bool) ir.Node {
 	n := ir.NewCallExpr(pos, ir.OCALL, fun, args)
 	n.IsDDD = dots
-	// n.Use will be changed to ir.CallUseStmt in g.stmt() if this call is
-	// just a statement (any return values are ignored).
-	n.Use = ir.CallUseExpr
 
 	if fun.Op() == ir.OTYPE {
 		// Actually a type conversion, not a function call.

src/cmd/compile/internal/noder/stmt.go

@@ -35,11 +35,7 @@ func (g *irgen) stmt(stmt syntax.Stmt) ir.Node {
 	case *syntax.BlockStmt:
 		return ir.NewBlockStmt(g.pos(stmt), g.blockStmt(stmt))
 	case *syntax.ExprStmt:
-		x := g.expr(stmt.X)
-		if call, ok := x.(*ir.CallExpr); ok {
-			call.Use = ir.CallUseStmt
-		}
-		return x
+		return g.expr(stmt.X)
 	case *syntax.SendStmt:
 		n := ir.NewSendStmt(g.pos(stmt), g.expr(stmt.Chan), g.expr(stmt.Value))
 		if n.Chan.Type().HasTParam() || n.Value.Type().HasTParam() {

src/cmd/compile/internal/noder/transform.go

@@ -326,7 +326,6 @@ assignOK:
 		stmt := stmt.(*ir.AssignListStmt)
 		stmt.SetOp(ir.OAS2FUNC)
 		r := rhs[0].(*ir.CallExpr)
-		r.Use = ir.CallUseList
 		rtyp := r.Type()
 
 		mismatched := false

src/cmd/compile/internal/typecheck/func.go

@@ -317,10 +317,6 @@ func tcFunc(n *ir.Func) {
 
 // tcCall typechecks an OCALL node.
 func tcCall(n *ir.CallExpr, top int) ir.Node {
-	n.Use = ir.CallUseExpr
-	if top == ctxStmt {
-		n.Use = ir.CallUseStmt
-	}
 	Stmts(n.Init()) // imported rewritten f(g()) calls (#30907)
 	n.X = typecheck(n.X, ctxExpr|ctxType|ctxCallee)
 	if n.X.Diag() {

src/cmd/compile/internal/typecheck/iexport.go

@@ -1922,7 +1922,6 @@ func (w *exportWriter) expr(n ir.Node) {
 		w.bool(n.IsDDD)
 		if go117ExportTypes {
 			w.exoticType(n.Type())
-			w.uint64(uint64(n.Use))
 		}
 
 	case ir.OMAKEMAP, ir.OMAKECHAN, ir.OMAKESLICE:

src/cmd/compile/internal/typecheck/iimport.go

@@ -1465,7 +1465,6 @@ func (r *importReader) node() ir.Node {
 		n.IsDDD = r.bool()
 		if go117ExportTypes {
 			n.SetType(r.exoticType())
-			n.Use = ir.CallUse(r.uint64())
 		}
 		return n
 

src/cmd/compile/internal/typecheck/stmt.go

@@ -201,7 +201,6 @@ assignOK:
 		stmt := stmt.(*ir.AssignListStmt)
 		stmt.SetOp(ir.OAS2FUNC)
 		r := rhs[0].(*ir.CallExpr)
-		r.Use = ir.CallUseList
 		rtyp := r.Type()
 
 		mismatched := false