From b09dbc69132aeee3571867cd269f5273290a2255 Mon Sep 17 00:00:00 2001 From: Russ Cox Date: Sat, 28 Nov 2020 00:54:58 -0500 Subject: [PATCH] [dev.regabi] cmd/compile: remove SetOp(OEMPTY) calls In preparation for OEMPTY being its own Node implementation, remove SetOp(OEMPTY) calls that assume other implementations can be turned into OEMPTY. Passes buildall w/ toolstash -cmp. Change-Id: Icac16d12548f35f52a5efa9d09dacf8260f42075 Reviewed-on: https://go-review.googlesource.com/c/go/+/274090 Trust: Russ Cox Run-TryBot: Russ Cox TryBot-Result: Go Bot Reviewed-by: Matthew Dempsky --- src/cmd/compile/internal/gc/sinit.go | 5 +++-- src/cmd/compile/internal/gc/typecheck.go | 3 +-- src/cmd/compile/internal/gc/walk.go | 9 ++++++--- 3 files changed, 10 insertions(+), 7 deletions(-) diff --git a/src/cmd/compile/internal/gc/sinit.go b/src/cmd/compile/internal/gc/sinit.go index e30663cfbb..fca81763c0 100644 --- a/src/cmd/compile/internal/gc/sinit.go +++ b/src/cmd/compile/internal/gc/sinit.go @@ -959,6 +959,9 @@ func anylit(n ir.Node, var_ ir.Node, init *ir.Nodes) { } } +// oaslit handles special composite literal assignments. +// It returns true if n's effects have been added to init, +// in which case n should be dropped from the program by the caller. func oaslit(n ir.Node, init *ir.Nodes) bool { if n.Left() == nil || n.Right() == nil { // not a special composite literal assignment @@ -990,8 +993,6 @@ func oaslit(n ir.Node, init *ir.Nodes) bool { anylit(n.Right(), n.Left(), init) } - n.SetOp(ir.OEMPTY) - n.SetRight(nil) return true } diff --git a/src/cmd/compile/internal/gc/typecheck.go b/src/cmd/compile/internal/gc/typecheck.go index 7037eddff0..0c4a3ad833 100644 --- a/src/cmd/compile/internal/gc/typecheck.go +++ b/src/cmd/compile/internal/gc/typecheck.go @@ -1985,8 +1985,7 @@ func typecheck1(n ir.Node, top int) (res ir.Node) { // Empty identifier is valid but useless. // Eliminate now to simplify life later. // See issues 7538, 11589, 11593. - n.SetOp(ir.OEMPTY) - n.SetLeft(nil) + n = ir.NodAt(n.Pos(), ir.OEMPTY, nil, nil) } case ir.ODEFER: diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go index db8791ee05..87fe36b08a 100644 --- a/src/cmd/compile/internal/gc/walk.go +++ b/src/cmd/compile/internal/gc/walk.go @@ -152,10 +152,12 @@ func walkstmt(n ir.Node) ir.Node { init := n.Init() n.PtrInit().Set(nil) n = walkexpr(n, &init) - n = addinit(n, init.Slice()) - if wascopy && n.Op() == ir.OCONVNOP { - n.SetOp(ir.OEMPTY) // don't leave plain values as statements. + if wascopy && n.Op() == ir.ONAME { + // copy rewrote to a statement list and a temp for the length. + // Throw away the temp to avoid plain values as statements. + n = ir.NodAt(n.Pos(), ir.OEMPTY, nil, nil) } + n = addinit(n, init.Slice()) // special case for a receive where we throw away // the value received. @@ -609,6 +611,7 @@ opswitch: } if oaslit(n, init) { + n = ir.NodAt(n.Pos(), ir.OEMPTY, nil, nil) break } -- 2.50.0