cmd/compile: treat empty and absent struct field tags as identical
Fixes #15439.
Change-Id: I5a32384c46e20f8db6968e5a9e854c45ab262fe4
Reviewed-on: https://go-review.googlesource.com/22429
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/gc/bexport.go b/src/cmd/compile/internal/gc/bexport.go
index bf1354c..c635129 100644
--- a/src/cmd/compile/internal/gc/bexport.go
+++ b/src/cmd/compile/internal/gc/bexport.go
@@ -720,18 +720,7 @@
p.pos(f.Sym.Def)
p.fieldName(f.Sym, f)
p.typ(f.Type)
- // TODO(gri) Do we care that a non-present tag cannot be distinguished
- // from a present but empty ta string? (reflect doesn't seem to make
- // a difference). Investigate.
- p.note(f.Note)
-}
-
-func (p *exporter) note(n *string) {
- var s string
- if n != nil {
- s = *n
- }
- p.string(s)
+ p.string(f.Note)
}
func (p *exporter) methodList(t *Type) {
@@ -847,7 +836,7 @@
// TODO(gri) This is compiler-specific (escape info).
// Move into compiler-specific section eventually?
// (Not having escape info causes tests to fail, e.g. runtime GCInfoTest)
- p.note(q.Note)
+ p.string(q.Note)
}
func parName(f *Field, numbered bool) string {
diff --git a/src/cmd/compile/internal/gc/bimport.go b/src/cmd/compile/internal/gc/bimport.go
index 3665bbd..7fed8b1 100644
--- a/src/cmd/compile/internal/gc/bimport.go
+++ b/src/cmd/compile/internal/gc/bimport.go
@@ -457,7 +457,7 @@
p.pos()
sym := p.fieldName()
typ := p.typ()
- note := p.note()
+ note := p.string()
var n *Node
if sym.Name != "" {
@@ -475,18 +475,11 @@
n = embedded(s, pkg)
n.Right = typenod(typ)
}
- n.SetVal(note)
+ n.SetVal(Val{U: note})
return n
}
-func (p *importer) note() (v Val) {
- if s := p.string(); s != "" {
- v.U = s
- }
- return
-}
-
// parser.go:hidden_interfacedcl_list
func (p *importer) methodList() (methods []*Node) {
if n := p.int(); n > 0 {
@@ -572,7 +565,7 @@
// TODO(gri) This is compiler-specific (escape info).
// Move into compiler-specific section eventually?
- n.SetVal(p.note())
+ n.SetVal(Val{U: p.string()})
return n
}
diff --git a/src/cmd/compile/internal/gc/dcl.go b/src/cmd/compile/internal/gc/dcl.go
index 7f6e167..ca9caf6 100644
--- a/src/cmd/compile/internal/gc/dcl.go
+++ b/src/cmd/compile/internal/gc/dcl.go
@@ -757,7 +757,7 @@
switch u := n.Val().U.(type) {
case string:
- f.Note = &u
+ f.Note = u
default:
Yyerror("field annotation must be string")
case nil:
diff --git a/src/cmd/compile/internal/gc/esc.go b/src/cmd/compile/internal/gc/esc.go
index 2f4e5fb..795e688 100644
--- a/src/cmd/compile/internal/gc/esc.go
+++ b/src/cmd/compile/internal/gc/esc.go
@@ -1181,7 +1181,7 @@
var tags [1 << (bitsPerOutputInTag + EscReturnBits)]string
// mktag returns the string representation for an escape analysis tag.
-func mktag(mask int) *string {
+func mktag(mask int) string {
switch mask & EscMask {
case EscNone, EscReturn:
break
@@ -1191,22 +1191,22 @@
}
if mask < len(tags) && tags[mask] != "" {
- return &tags[mask]
+ return tags[mask]
}
s := fmt.Sprintf("esc:0x%x", mask)
if mask < len(tags) {
tags[mask] = s
}
- return &s
+ return s
}
// parsetag decodes an escape analysis tag and returns the esc value.
-func parsetag(note *string) uint16 {
- if note == nil || !strings.HasPrefix(*note, "esc:") {
+func parsetag(note string) uint16 {
+ if !strings.HasPrefix(note, "esc:") {
return EscUnknown
}
- n, _ := strconv.ParseInt((*note)[4:], 0, 0)
+ n, _ := strconv.ParseInt(note[4:], 0, 0)
em := uint16(n)
if em == 0 {
return EscNone
@@ -1268,7 +1268,7 @@
// escassignfromtag models the input-to-output assignment flow of one of a function
// calls arguments, where the flow is encoded in "note".
-func escassignfromtag(e *EscState, note *string, dsts Nodes, src *Node) uint16 {
+func escassignfromtag(e *EscState, note string, dsts Nodes, src *Node) uint16 {
em := parsetag(note)
if src.Op == OLITERAL {
return em
@@ -1997,7 +1997,7 @@
}
Warnl(func_.Lineno, "%v assuming %v is unsafe uintptr", funcSym(func_), name)
}
- t.Note = &unsafeUintptrTag
+ t.Note = unsafeUintptrTag
}
}
diff --git a/src/cmd/compile/internal/gc/fmt.go b/src/cmd/compile/internal/gc/fmt.go
index 27ece1d..3bd3874 100644
--- a/src/cmd/compile/internal/gc/fmt.go
+++ b/src/cmd/compile/internal/gc/fmt.go
@@ -1700,8 +1700,8 @@
// (The escape analysis tags do not apply to func vars.)
// But it must not suppress struct field tags.
// See golang.org/issue/13777 and golang.org/issue/14331.
- if flag&FmtShort == 0 && (!fmtbody || !f.Funarg) && f.Note != nil {
- str += " " + strconv.Quote(*f.Note)
+ if flag&FmtShort == 0 && (!fmtbody || !f.Funarg) && f.Note != "" {
+ str += " " + strconv.Quote(f.Note)
}
if fmtmode == FTypeId && (sf&FmtUnsigned != 0) {
diff --git a/src/cmd/compile/internal/gc/order.go b/src/cmd/compile/internal/gc/order.go
index 7373479..7e7bda4 100644
--- a/src/cmd/compile/internal/gc/order.go
+++ b/src/cmd/compile/internal/gc/order.go
@@ -373,7 +373,7 @@
if t == nil {
break
}
- if t.Note != nil && *t.Note == unsafeUintptrTag {
+ if t.Note == unsafeUintptrTag {
xp := n.List.Addr(i)
for (*xp).Op == OCONVNOP && !(*xp).Type.IsPtr() {
xp = &(*xp).Left
diff --git a/src/cmd/compile/internal/gc/reflect.go b/src/cmd/compile/internal/gc/reflect.go
index 727b993..a578820 100644
--- a/src/cmd/compile/internal/gc/reflect.go
+++ b/src/cmd/compile/internal/gc/reflect.go
@@ -501,14 +501,11 @@
// dnameField dumps a reflect.name for a struct field.
func dnameField(s *Sym, ot int, ft *Field) int {
- var name, tag string
+ var name string
if ft.Sym != nil && ft.Embedded == 0 {
name = ft.Sym.Name
}
- if ft.Note != nil {
- tag = *ft.Note
- }
- nsym := dname(name, tag, nil, isExportedField(ft))
+ nsym := dname(name, ft.Note, nil, isExportedField(ft))
return dsymptrLSym(Linksym(s), ot, nsym, 0)
}
diff --git a/src/cmd/compile/internal/gc/subr.go b/src/cmd/compile/internal/gc/subr.go
index 38f21eb..f2f2a70 100644
--- a/src/cmd/compile/internal/gc/subr.go
+++ b/src/cmd/compile/internal/gc/subr.go
@@ -619,10 +619,6 @@
return 0
}
-func eqnote(a, b *string) bool {
- return a == b || a != nil && b != nil && *a == *b
-}
-
// Eqtype reports whether t1 and t2 are identical, following the spec rules.
//
// Any cyclic type must go through a named type, and if one is
@@ -670,7 +666,7 @@
t1, i1 := IterFields(t1)
t2, i2 := IterFields(t2)
for ; t1 != nil && t2 != nil; t1, t2 = i1.Next(), i2.Next() {
- if t1.Sym != t2.Sym || t1.Embedded != t2.Embedded || !eqtype1(t1.Type, t2.Type, assumedEqual) || !eqnote(t1.Note, t2.Note) {
+ if t1.Sym != t2.Sym || t1.Embedded != t2.Embedded || !eqtype1(t1.Type, t2.Type, assumedEqual) || t1.Note != t2.Note {
return false
}
}
diff --git a/src/cmd/compile/internal/gc/type.go b/src/cmd/compile/internal/gc/type.go
index da295bb..9f049ba 100644
--- a/src/cmd/compile/internal/gc/type.go
+++ b/src/cmd/compile/internal/gc/type.go
@@ -300,7 +300,7 @@
// or interface Type.
Offset int64
- Note *string // literal string annotation
+ Note string // literal string annotation
}
// End returns the offset of the first byte immediately after this field.
@@ -1003,15 +1003,7 @@
return cmpForNe(t1.Embedded < x1.Embedded)
}
if t1.Note != x1.Note {
- if t1.Note == nil {
- return ssa.CMPlt
- }
- if x1.Note == nil {
- return ssa.CMPgt
- }
- if *t1.Note != *x1.Note {
- return cmpForNe(*t1.Note < *x1.Note)
- }
+ return cmpForNe(t1.Note < x1.Note)
}
if c := t1.Sym.cmpsym(x1.Sym); c != ssa.CMPeq {
return c
diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go
index e8fee67..0c7c5fa 100644
--- a/src/cmd/compile/internal/gc/walk.go
+++ b/src/cmd/compile/internal/gc/walk.go
@@ -3807,7 +3807,7 @@
if field == nil {
Fatalf("usefield %v %v without paramfld", n.Left.Type, n.Sym)
}
- if field.Note == nil || !strings.Contains(*field.Note, "go:\"track\"") {
+ if !strings.Contains(field.Note, "go:\"track\"") {
return
}
