[dev.regabi] cmd/compile: make ir.Name the ONAME Node implementation

Before this CL, an ONAME Node was represented by three structs
linked together: a node, a Name, and a Param. Previous CLs removed
OLABEL and OPACK from the set of nodes that knew about Name.
Now Name can be repurposed to *be* the ONAME Node implementation,
replacing three linked structs totaling 152+64+88 = 304 bytes (64-bit)
with a single 232-byte struct.

Many expressions in the code become simpler as well, without having
to use .Param. and sometimes even .Name().
(For a node n where n.Name() != nil, n.Name() == n.(*Name) now.)

Passes buildall w/ toolstash -cmp.

Change-Id: Ie719f1285c05623b9fd2faaa059e5b360a64b3be
Reviewed-on: https://go-review.googlesource.com/c/go/+/274094
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This commit is contained in:
Russ Cox 2020-11-28 01:41:13 -05:00
parent f6106d195d
commit 862f638a89
24 changed files with 256 additions and 265 deletions

View file

@ -0,0 +1,47 @@
// Copyright 2020 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package ir
import (
"cmd/compile/internal/types"
)
// A miniStmt is a miniNode with extra fields common to expressions.
// TODO(rsc): Once we are sure about the contents, compact the bools
// into a bit field and leave extra bits available for implementations
// embedding miniExpr. Right now there are ~60 unused bits sitting here.
type miniExpr struct {
miniNode
typ *types.Type
init Nodes // TODO(rsc): Don't require every Node to have an init
opt interface{} // TODO(rsc): Don't require every Node to have an opt?
flags bitset8
}
const (
miniExprHasCall = 1 << iota
miniExprImplicit
miniExprNonNil
miniExprTransient
miniExprBounded
)
func (n *miniExpr) Type() *types.Type { return n.typ }
func (n *miniExpr) SetType(x *types.Type) { n.typ = x }
func (n *miniExpr) Opt() interface{} { return n.opt }
func (n *miniExpr) SetOpt(x interface{}) { n.opt = x }
func (n *miniExpr) HasCall() bool { return n.flags&miniExprHasCall != 0 }
func (n *miniExpr) SetHasCall(b bool) { n.flags.set(miniExprHasCall, b) }
func (n *miniExpr) Implicit() bool { return n.flags&miniExprImplicit != 0 }
func (n *miniExpr) SetImplicit(b bool) { n.flags.set(miniExprImplicit, b) }
func (n *miniExpr) NonNil() bool { return n.flags&miniExprNonNil != 0 }
func (n *miniExpr) MarkNonNil() { n.flags |= miniExprNonNil }
func (n *miniExpr) Transient() bool { return n.flags&miniExprTransient != 0 }
func (n *miniExpr) SetTransient(b bool) { n.flags.set(miniExprTransient, b) }
func (n *miniExpr) Bounded() bool { return n.flags&miniExprBounded != 0 }
func (n *miniExpr) SetBounded(b bool) { n.flags.set(miniExprBounded, b) }
func (n *miniExpr) Init() Nodes { return n.init }
func (n *miniExpr) PtrInit() *Nodes { return &n.init }
func (n *miniExpr) SetInit(x Nodes) { n.init = x }