qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-18 11:34:45 -07:00
Code Releases Activity

cmd/compile: use a Sym type instead of interface{} for symbolic offsets

Browse Source 
Will help with strongly typed rewrite rules.

Change-Id: Ifbf316a49f4081322b3b8f13bc962713437d9aba
Reviewed-on: https://go-review.googlesource.com/c/go/+/227785
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
This commit is contained in:
Keith Randall 2020-04-09 20:28:55 -07:00
parent 782fcb44b9
commit ea7126fe14
9 changed files with 81 additions and 53 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
src/cmd/compile/internal/amd64/ssa.go
View File

@ -1101,7 +1101,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
p.From.Reg = x86.REG_AX
p.To.Type = obj.TYPE_MEM
p.To.Reg = v.Args[0].Reg()
gc.AddAux(&p.To, v)
if logopt.Enabled() {
logopt.LogOpt(v.Pos, "nilcheck", "genssa", v.Block.Func.Name)
}

14
src/cmd/compile/internal/gc/ssa.go
View File

@ -6346,20 +6346,6 @@ func (s *SSAGenState) FPJump(b, next *ssa.Block, jumps *[2][2]FloatingEQNEJump)
}
}
func AuxOffset(v *ssa.Value) (offset int64) {
if v.Aux == nil {
return 0
}
n, ok := v.Aux.(*Node)
if !ok {
v.Fatalf("bad aux type in %s\n", v.LongString())
}
if n.Class() == PAUTO {
return n.Xoffset
}
return 0
}
// AddAux adds the offset in the aux fields (AuxInt and Aux) of v to a.
func AddAux(a *obj.Addr, v *ssa.Value) {
AddAux2(a, v, v.AuxInt)

4
src/cmd/compile/internal/gc/syntax.go
View File

@ -311,6 +311,10 @@ func (n *Node) pkgFuncName() string {
return p + "." + s.Name
}
// The compiler needs *Node to be assignable to cmd/compile/internal/ssa.Sym.
func (n *Node) CanBeAnSSASym() {
}
// Name holds Node fields used only by named nodes (ONAME, OTYPE, OPACK, OLABEL, some OLITERAL).
type Name struct {
Pack *Node // real package for import . names

7
src/cmd/compile/internal/ppc64/ssa.go
View File

@ -654,15 +654,8 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
case ssa.OpPPC64ANDCCconst:
p := s.Prog(v.Op.Asm())
p.Reg = v.Args[0].Reg()
if v.Aux != nil {
p.From.Type = obj.TYPE_CONST
p.From.Offset = gc.AuxOffset(v)
} else {
p.From.Type = obj.TYPE_CONST
p.From.Offset = v.AuxInt
}
p.To.Type = obj.TYPE_REG
p.To.Reg = ppc64.REGTMP // discard result

66
src/cmd/compile/internal/ssa/gen/rulegen.go
View File

@ -479,11 +479,15 @@ func (u *unusedInspector) node(node ast.Node) {
u.exprs(node.Lhs)
break
}
if len(node.Lhs) != 1 {
lhs := node.Lhs
if len(lhs) == 2 && lhs[1].(*ast.Ident).Name == "_" {
lhs = lhs[:1]
}
if len(lhs) != 1 {
panic("no support for := with multiple names")
}
name := node.Lhs[0].(*ast.Ident)
name := lhs[0].(*ast.Ident)
obj := &object{
name: name.Name,
pos: name.NamePos,
@ -615,6 +619,16 @@ func fprint(w io.Writer, n Node) {
fprint(w, n)
}
fmt.Fprintf(w, "}\n")
case *If:
fmt.Fprintf(w, "if ")
fprint(w, n.expr)
fmt.Fprintf(w, " {\n")
fprint(w, n.stmt)
if n.alt != nil {
fmt.Fprintf(w, "} else {\n")
fprint(w, n.alt)
}
fmt.Fprintf(w, "}\n")
case *Case:
fmt.Fprintf(w, "case ")
fprint(w, n.expr)
@ -657,6 +671,10 @@ func fprint(w io.Writer, n Node) {
fmt.Fprintf(w, "%s := ", n.name)
fprint(w, n.value)
fmt.Fprintln(w)
case *Declare2:
fmt.Fprintf(w, "%s, %s := ", n.name1, n.name2)
fprint(w, n.value)
fmt.Fprintln(w)
case *CondBreak:
fmt.Fprintf(w, "if ")
fprint(w, n.expr)
@ -721,7 +739,7 @@ func (w *bodyBase) add(node Statement) {
w.list = append(w.list, node)
}
// declared reports if the body contains a Declare with the given name.
// declared reports if the body contains a Declare or Declare2 with the given name.
func (w *bodyBase) declared(name string) bool {
if name == "nil" {
// Treat "nil" as having already been declared.
@ -732,6 +750,9 @@ func (w *bodyBase) declared(name string) bool {
if decl, ok := s.(*Declare); ok && decl.name == name {
return true
}
if decl, ok := s.(*Declare2); ok && (decl.name1 == name || decl.name2 == name) {
return true
}
}
return false
}
@ -754,6 +775,11 @@ type (
suffix string
arglen int32 // if kind == "Value", number of args for this op
}
If struct {
expr ast.Expr
stmt Statement
alt Statement
}
Switch struct {
bodyBase // []*Case
expr ast.Expr
@ -776,6 +802,11 @@ type (
name string
value ast.Expr
}
Declare2 struct {
name1, name2 string
value ast.Expr
}
// TODO: implement CondBreak as If + Break instead?
CondBreak struct {
expr ast.Expr
insideCommuteLoop bool
@ -816,6 +847,12 @@ func declf(name, format string, a ...interface{}) *Declare {
return &Declare{name, exprf(format, a...)}
}
// decl2f constructs a simple "name1, name2 := value" declaration, using exprf for its
// value.
func decl2f(name1, name2, format string, a ...interface{}) *Declare2 {
return &Declare2{name1, name2, exprf(format, a...)}
}
// breakf constructs a simple "if cond { break }" statement, using exprf for its
// condition.
func breakf(format string, a ...interface{}) *CondBreak {
@ -1006,12 +1043,11 @@ func genMatch0(rr *RuleRewrite, arch arch, match, v string, cnt map[string]int,
if !token.IsIdentifier(e.name) || rr.declared(e.name) {
switch e.field {
case "Aux":
if e.dclType == "interface{}" {
// see TODO above
rr.add(breakf("%s.%s != %s", v, e.field, e.dclType, e.name))
} else {
rr.add(breakf("%s.%s.(%s) != %s", v, e.field, e.dclType, e.name))
}
rr.add(&If{
expr: exprf("%s.%s == nil", v, e.field),
stmt: breakf("%s == nil", e.name),
alt: breakf("%s.%s.(%s) == %s", v, e.field, e.dclType, e.name),
})
case "AuxInt":
rr.add(breakf("%s(%s.%s) != %s", e.dclType, v, e.field, e.name))
case "Type":
@ -1020,9 +1056,9 @@ func genMatch0(rr *RuleRewrite, arch arch, match, v string, cnt map[string]int,
} else {
switch e.field {
case "Aux":
if e.dclType == "interface{}" {
if e.dclType == "Sym" {
// TODO: kind of a hack - allows nil interface through
rr.add(declf(e.name, "%s.%s", v, e.field))
rr.add(decl2f(e.name, "_", "%s.Aux.(Sym)", v))
} else {
rr.add(declf(e.name, "%s.%s.(%s)", v, e.field, e.dclType))
}
@ -1719,13 +1755,11 @@ func (op opData) auxType() string {
return "string"
case "Sym":
// Note: a Sym can be an *obj.LSym, a *gc.Node, or nil.
// TODO: provide an interface for this. Use a singleton to
// represent "no offset".
return "interface{}"
return "Sym"
case "SymOff":
return "interface{}"
return "Sym"
case "SymValAndOff":
return "interface{}"
return "Sym"
case "Typ":
return "*types.Type"
case "TypSize":

12
src/cmd/compile/internal/ssa/op.go
View File

@ -78,7 +78,7 @@ const (
auxFloat32 // auxInt is a float32 (encoded with math.Float64bits)
auxFloat64 // auxInt is a float64 (encoded with math.Float64bits)
auxString // aux is a string
auxSym // aux is a symbol (a *gc.Node for locals or an *obj.LSym for globals)
auxSym // aux is a symbol (a *gc.Node for locals, an *obj.LSym for globals, or nil for none)
auxSymOff // aux is a symbol, auxInt is an offset
auxSymValAndOff // aux is a symbol, auxInt is a ValAndOff
auxTyp // aux is a type
@ -102,6 +102,16 @@ const (
SymNone SymEffect = 0
)
// A Sym represents a symbolic offset from a base register.
// Currently a Sym can be one of 3 things:
// - a *gc.Node, for an offset from SP (the stack pointer)
// - a *obj.LSym, for an offset from SB (the global pointer)
// - nil, for no offset
type Sym interface {
String() string
CanBeAnSSASym()
}
// A ValAndOff is used by the several opcodes. It holds
// both a value and a pointer offset.
// A ValAndOff is intended to be encoded into an AuxInt field.

16
src/cmd/compile/internal/ssa/rewriteAMD64.go
View File

@ -6946,7 +6946,7 @@ func rewriteValueAMD64_OpAMD64CMPBconst(v *Value) bool {
break
}
off := int32(l.AuxInt)
sym := l.Aux
sym, _ := l.Aux.(Sym)
mem := l.Args[1]
ptr := l.Args[0]
if !(l.Uses == 1 && clobber(l)) {
@ -6957,7 +6957,7 @@ func rewriteValueAMD64_OpAMD64CMPBconst(v *Value) bool {
v.copyOf(v0)
var _auxint ValAndOff = makeValAndOff32(int32(c), off)
v0.AuxInt = int64(_auxint)
var _aux interface{} = sym
var _aux Sym = sym
v0.Aux = _aux
v0.AddArg2(ptr, mem)
return true
@ -7333,7 +7333,7 @@ func rewriteValueAMD64_OpAMD64CMPLconst(v *Value) bool {
break
}
off := int32(l.AuxInt)
sym := l.Aux
sym, _ := l.Aux.(Sym)
mem := l.Args[1]
ptr := l.Args[0]
if !(l.Uses == 1 && clobber(l)) {
@ -7344,7 +7344,7 @@ func rewriteValueAMD64_OpAMD64CMPLconst(v *Value) bool {
v.copyOf(v0)
var _auxint ValAndOff = makeValAndOff32(c, off)
v0.AuxInt = int64(_auxint)
var _aux interface{} = sym
var _aux Sym = sym
v0.Aux = _aux
v0.AddArg2(ptr, mem)
return true
@ -7900,7 +7900,7 @@ func rewriteValueAMD64_OpAMD64CMPQconst(v *Value) bool {
break
}
off := int32(l.AuxInt)
sym := l.Aux
sym, _ := l.Aux.(Sym)
mem := l.Args[1]
ptr := l.Args[0]
if !(l.Uses == 1 && clobber(l)) {
@ -7911,7 +7911,7 @@ func rewriteValueAMD64_OpAMD64CMPQconst(v *Value) bool {
v.copyOf(v0)
var _auxint ValAndOff = makeValAndOff32(c, off)
v0.AuxInt = int64(_auxint)
var _aux interface{} = sym
var _aux Sym = sym
v0.Aux = _aux
v0.AddArg2(ptr, mem)
return true
@ -8272,7 +8272,7 @@ func rewriteValueAMD64_OpAMD64CMPWconst(v *Value) bool {
break
}
off := int32(l.AuxInt)
sym := l.Aux
sym, _ := l.Aux.(Sym)
mem := l.Args[1]
ptr := l.Args[0]
if !(l.Uses == 1 && clobber(l)) {
@ -8283,7 +8283,7 @@ func rewriteValueAMD64_OpAMD64CMPWconst(v *Value) bool {
v.copyOf(v0)
var _auxint ValAndOff = makeValAndOff32(int32(c), off)
v0.AuxInt = int64(_auxint)
var _aux interface{} = sym
var _aux Sym = sym
v0.Aux = _aux
v0.AddArg2(ptr, mem)
return true

4
src/cmd/compile/internal/ssa/rewritegeneric.go
View File

@ -3953,7 +3953,7 @@ func rewriteValuegeneric_OpConstString(v *Value) bool {
}
v.reset(OpStringMake)
v0 := b.NewValue0(v.Pos, OpAddr, typ.BytePtr)
var _aux interface{} = fe.StringData(str)
var _aux Sym = fe.StringData(str)
v0.Aux = _aux
v1 := b.NewValue0(v.Pos, OpSB, typ.Uintptr)
v0.AddArg(v1)
@ -3973,7 +3973,7 @@ func rewriteValuegeneric_OpConstString(v *Value) bool {
}
v.reset(OpStringMake)
v0 := b.NewValue0(v.Pos, OpAddr, typ.BytePtr)
var _aux interface{} = fe.StringData(str)
var _aux Sym = fe.StringData(str)
v0.Aux = _aux
v1 := b.NewValue0(v.Pos, OpSB, typ.Uintptr)
v0.AddArg(v1)

6
src/cmd/internal/obj/link.go
View File

@ -601,12 +601,14 @@ func (a Attribute) TextAttrString() string {
return s
}
// The compiler needs LSym to satisfy fmt.Stringer, because it stores
// an LSym in ssa.ExternSymbol.
func (s *LSym) String() string {
return s.Name
}
// The compiler needs *LSym to be assignable to cmd/compile/internal/ssa.Sym.
func (s *LSym) CanBeAnSSASym() {
}
type Pcln struct {
Pcsp Pcdata
Pcfile Pcdata