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mirror of https://github.com/golang/go synced 2024-09-23 17:20:13 -06:00

[dev.regabi] cmd/compile: refactoring prep for ConstExpr

The next CL adds ConstExpr, which is a more memory efficient
representation for constant expressions than Name. However, currently
a bunch of Val helper methods are defined on Name. This CL changes
them into standalone functions that work with any Node.Val
implementation.

There's also an existing standalone function named Int64Val, which
takes a Type argument to specify what type of integer is expected. So
to avoid collisions, this CL renames it to IntVal.

Passes buildall w/ toolstash -cmp.

[git-generate]
cd src/cmd/compile/internal/ir
rf 'mv Int64Val IntVal'
sed -i -E -e 's/\(n \*Name\) (CanInt64|((I|Ui)nt64|Bool|String)Val)\(/\1(n Node/' name.go

cd ../gc
rf '
ex {
  import "cmd/compile/internal/ir"
  var n ir.Node
  n.CanInt64() -> ir.CanInt64(n)
  n.Int64Val() -> ir.Int64Val(n)
  n.Uint64Val() -> ir.Uint64Val(n)
  n.BoolVal() -> ir.BoolVal(n)
  n.StringVal() -> ir.StringVal(n)
}
'

cd ../ir
rf '
mv CanInt64 Int64Val Uint64Val BoolVal StringVal val.go
rm Node.CanInt64 Node.Int64Val Node.Uint64Val Node.BoolVal Node.StringVal
'

Change-Id: I003140bda1690d770fd608bdd087e6d4ff00fb1f
Reviewed-on: https://go-review.googlesource.com/c/go/+/275032
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
This commit is contained in:
Matthew Dempsky 2020-12-02 23:55:42 -08:00
parent 7e81135be7
commit beb5e05404
13 changed files with 113 additions and 118 deletions

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@ -526,7 +526,7 @@ func evalConst(n ir.Node) ir.Node {
if need == 1 {
var strs []string
for _, c := range s {
strs = append(strs, c.StringVal())
strs = append(strs, ir.StringVal(c))
}
return origConst(n, constant.MakeString(strings.Join(strs, "")))
}
@ -537,7 +537,7 @@ func evalConst(n ir.Node) ir.Node {
var strs []string
i2 := i
for i2 < len(s) && ir.IsConst(s[i2], constant.String) {
strs = append(strs, s[i2].StringVal())
strs = append(strs, ir.StringVal(s[i2]))
i2++
}
@ -558,7 +558,7 @@ func evalConst(n ir.Node) ir.Node {
switch nl.Type().Kind() {
case types.TSTRING:
if ir.IsConst(nl, constant.String) {
return origIntConst(n, int64(len(nl.StringVal())))
return origIntConst(n, int64(len(ir.StringVal(nl))))
}
case types.TARRAY:
if !hascallchan(nl) {
@ -780,7 +780,7 @@ func indexconst(n ir.Node) int64 {
if doesoverflow(v, types.Types[types.TINT]) {
return -2
}
return ir.Int64Val(types.Types[types.TINT], v)
return ir.IntVal(types.Types[types.TINT], v)
}
// isGoConst reports whether n is a Go language constant (as opposed to a

View File

@ -1769,7 +1769,7 @@ func heapAllocReason(n ir.Node) string {
if !smallintconst(r) {
return "non-constant size"
}
if t := n.Type(); t.Elem().Width != 0 && r.Int64Val() >= maxImplicitStackVarSize/t.Elem().Width {
if t := n.Type(); t.Elem().Width != 0 && ir.Int64Val(r) >= maxImplicitStackVarSize/t.Elem().Width {
return "too large for stack"
}
}

View File

@ -807,7 +807,7 @@ func (p *noder) sum(x syntax.Expr) ir.Node {
n := p.expr(x)
if ir.IsConst(n, constant.String) && n.Sym() == nil {
nstr = n
chunks = append(chunks, nstr.StringVal())
chunks = append(chunks, ir.StringVal(nstr))
}
for i := len(adds) - 1; i >= 0; i-- {
@ -817,12 +817,12 @@ func (p *noder) sum(x syntax.Expr) ir.Node {
if ir.IsConst(r, constant.String) && r.Sym() == nil {
if nstr != nil {
// Collapse r into nstr instead of adding to n.
chunks = append(chunks, r.StringVal())
chunks = append(chunks, ir.StringVal(r))
continue
}
nstr = r
chunks = append(chunks, nstr.StringVal())
chunks = append(chunks, ir.StringVal(nstr))
} else {
if len(chunks) > 1 {
nstr.SetVal(constant.MakeString(strings.Join(chunks, "")))

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@ -263,7 +263,7 @@ func dumpGlobalConst(n ir.Node) {
return
}
}
base.Ctxt.DwarfIntConst(base.Ctxt.Pkgpath, n.Sym().Name, typesymname(t), ir.Int64Val(t, v))
base.Ctxt.DwarfIntConst(base.Ctxt.Pkgpath, n.Sym().Name, typesymname(t), ir.IntVal(t, v))
}
func dumpglobls() {
@ -598,7 +598,7 @@ func litsym(n, c ir.Node, wid int) {
s.WriteInt(base.Ctxt, n.Offset(), wid, i)
case constant.Int:
s.WriteInt(base.Ctxt, n.Offset(), wid, ir.Int64Val(n.Type(), u))
s.WriteInt(base.Ctxt, n.Offset(), wid, ir.IntVal(n.Type(), u))
case constant.Float:
f, _ := constant.Float64Val(u)

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@ -1107,7 +1107,7 @@ func (o *Order) expr(n, lhs ir.Node) ir.Node {
haslit := false
for _, n1 := range n.List().Slice() {
hasbyte = hasbyte || n1.Op() == ir.OBYTES2STR
haslit = haslit || n1.Op() == ir.OLITERAL && len(n1.StringVal()) != 0
haslit = haslit || n1.Op() == ir.OLITERAL && len(ir.StringVal(n1)) != 0
}
if haslit && hasbyte {
@ -1278,7 +1278,7 @@ func (o *Order) expr(n, lhs ir.Node) ir.Node {
var t *types.Type
switch n.Op() {
case ir.OSLICELIT:
t = types.NewArray(n.Type().Elem(), n.Right().Int64Val())
t = types.NewArray(n.Type().Elem(), ir.Int64Val(n.Right()))
case ir.OCALLPART:
t = partialCallType(n)
}

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@ -134,7 +134,7 @@ func (s *InitSchedule) staticcopy(l ir.Node, r ir.Node) bool {
case ir.OSLICELIT:
// copy slice
a := s.inittemps[r]
slicesym(l, a, r.Right().Int64Val())
slicesym(l, a, ir.Int64Val(r.Right()))
return true
case ir.OARRAYLIT, ir.OSTRUCTLIT:
@ -213,7 +213,7 @@ func (s *InitSchedule) staticassign(l ir.Node, r ir.Node) bool {
case ir.OSTR2BYTES:
if l.Class() == ir.PEXTERN && r.Left().Op() == ir.OLITERAL {
sval := r.Left().StringVal()
sval := ir.StringVal(r.Left())
slicebytes(l, sval)
return true
}
@ -221,7 +221,7 @@ func (s *InitSchedule) staticassign(l ir.Node, r ir.Node) bool {
case ir.OSLICELIT:
s.initplan(r)
// Init slice.
bound := r.Right().Int64Val()
bound := ir.Int64Val(r.Right())
ta := types.NewArray(r.Type().Elem(), bound)
ta.SetNoalg(true)
a := staticname(ta)
@ -418,7 +418,7 @@ func getdyn(n ir.Node, top bool) initGenType {
if !top {
return initDynamic
}
if n.Right().Int64Val()/4 > int64(n.List().Len()) {
if ir.Int64Val(n.Right())/4 > int64(n.List().Len()) {
// <25% of entries have explicit values.
// Very rough estimation, it takes 4 bytes of instructions
// to initialize 1 byte of result. So don't use a static
@ -594,12 +594,12 @@ func isSmallSliceLit(n ir.Node) bool {
r := n.Right()
return smallintconst(r) && (n.Type().Elem().Width == 0 || r.Int64Val() <= smallArrayBytes/n.Type().Elem().Width)
return smallintconst(r) && (n.Type().Elem().Width == 0 || ir.Int64Val(r) <= smallArrayBytes/n.Type().Elem().Width)
}
func slicelit(ctxt initContext, n ir.Node, var_ ir.Node, init *ir.Nodes) {
// make an array type corresponding the number of elements we have
t := types.NewArray(n.Type().Elem(), n.Right().Int64Val())
t := types.NewArray(n.Type().Elem(), ir.Int64Val(n.Right()))
dowidth(t)
if ctxt == inNonInitFunction {
@ -997,7 +997,7 @@ func oaslit(n ir.Node, init *ir.Nodes) bool {
func getlit(lit ir.Node) int {
if smallintconst(lit) {
return int(lit.Int64Val())
return int(ir.Int64Val(lit))
}
return -1
}

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@ -1271,7 +1271,7 @@ func (s *state) stmt(n ir.Node) {
// We're assigning a slicing operation back to its source.
// Don't write back fields we aren't changing. See issue #14855.
i, j, k := rhs.SliceBounds()
if i != nil && (i.Op() == ir.OLITERAL && i.Val().Kind() == constant.Int && i.Int64Val() == 0) {
if i != nil && (i.Op() == ir.OLITERAL && i.Val().Kind() == constant.Int && ir.Int64Val(i) == 0) {
// [0:...] is the same as [:...]
i = nil
}
@ -1301,7 +1301,7 @@ func (s *state) stmt(n ir.Node) {
case ir.OIF:
if ir.IsConst(n.Left(), constant.Bool) {
s.stmtList(n.Left().Init())
if n.Left().BoolVal() {
if ir.BoolVal(n.Left()) {
s.stmtList(n.Body())
} else {
s.stmtList(n.Rlist())
@ -2041,7 +2041,7 @@ func (s *state) expr(n ir.Node) *ssa.Value {
case ir.OLITERAL:
switch u := n.Val(); u.Kind() {
case constant.Int:
i := ir.Int64Val(n.Type(), u)
i := ir.IntVal(n.Type(), u)
switch n.Type().Size() {
case 1:
return s.constInt8(n.Type(), int8(i))
@ -2624,7 +2624,7 @@ func (s *state) expr(n ir.Node) *ssa.Value {
// Replace "abc"[1] with 'b'.
// Delayed until now because "abc"[1] is not an ideal constant.
// See test/fixedbugs/issue11370.go.
return s.newValue0I(ssa.OpConst8, types.Types[types.TUINT8], int64(int8(n.Left().StringVal()[n.Right().Int64Val()])))
return s.newValue0I(ssa.OpConst8, types.Types[types.TUINT8], int64(int8(ir.StringVal(n.Left())[ir.Int64Val(n.Right())])))
}
a := s.expr(n.Left())
i := s.expr(n.Right())
@ -2633,7 +2633,7 @@ func (s *state) expr(n ir.Node) *ssa.Value {
ptrtyp := s.f.Config.Types.BytePtr
ptr := s.newValue1(ssa.OpStringPtr, ptrtyp, a)
if ir.IsConst(n.Right(), constant.Int) {
ptr = s.newValue1I(ssa.OpOffPtr, ptrtyp, n.Right().Int64Val(), ptr)
ptr = s.newValue1I(ssa.OpOffPtr, ptrtyp, ir.Int64Val(n.Right()), ptr)
} else {
ptr = s.newValue2(ssa.OpAddPtr, ptrtyp, ptr, i)
}

View File

@ -365,8 +365,8 @@ func (s *exprSwitch) flush() {
// all we need here is consistency. We respect this
// sorting below.
sort.Slice(cc, func(i, j int) bool {
si := cc[i].lo.StringVal()
sj := cc[j].lo.StringVal()
si := ir.StringVal(cc[i].lo)
sj := ir.StringVal(cc[j].lo)
if len(si) != len(sj) {
return len(si) < len(sj)
}
@ -375,7 +375,7 @@ func (s *exprSwitch) flush() {
// runLen returns the string length associated with a
// particular run of exprClauses.
runLen := func(run []exprClause) int64 { return int64(len(run[0].lo.StringVal())) }
runLen := func(run []exprClause) int64 { return int64(len(ir.StringVal(run[0].lo))) }
// Collapse runs of consecutive strings with the same length.
var runs [][]exprClause
@ -411,7 +411,7 @@ func (s *exprSwitch) flush() {
merged := cc[:1]
for _, c := range cc[1:] {
last := &merged[len(merged)-1]
if last.jmp == c.jmp && last.hi.Int64Val()+1 == c.lo.Int64Val() {
if last.jmp == c.jmp && ir.Int64Val(last.hi)+1 == ir.Int64Val(c.lo) {
last.hi = c.lo
} else {
merged = append(merged, c)
@ -446,7 +446,7 @@ func (c *exprClause) test(exprname ir.Node) ir.Node {
// Optimize "switch true { ...}" and "switch false { ... }".
if ir.IsConst(exprname, constant.Bool) && !c.lo.Type().IsInterface() {
if exprname.BoolVal() {
if ir.BoolVal(exprname) {
return c.lo
} else {
return ir.NodAt(c.pos, ir.ONOT, c.lo, nil)

View File

@ -1054,8 +1054,8 @@ func typecheck1(n ir.Node, top int) (res ir.Node) {
base.Errorf("invalid %s index %v (index must be non-negative)", why, n.Right())
} else if t.IsArray() && constant.Compare(x, token.GEQ, constant.MakeInt64(t.NumElem())) {
base.Errorf("invalid array index %v (out of bounds for %d-element array)", n.Right(), t.NumElem())
} else if ir.IsConst(n.Left(), constant.String) && constant.Compare(x, token.GEQ, constant.MakeInt64(int64(len(n.Left().StringVal())))) {
base.Errorf("invalid string index %v (out of bounds for %d-byte string)", n.Right(), len(n.Left().StringVal()))
} else if ir.IsConst(n.Left(), constant.String) && constant.Compare(x, token.GEQ, constant.MakeInt64(int64(len(ir.StringVal(n.Left()))))) {
base.Errorf("invalid string index %v (out of bounds for %d-byte string)", n.Right(), len(ir.StringVal(n.Left())))
} else if doesoverflow(x, types.Types[types.TINT]) {
base.Errorf("invalid %s index %v (index too large)", why, n.Right())
}
@ -1146,11 +1146,11 @@ func typecheck1(n ir.Node, top int) (res ir.Node) {
l = defaultlit(l, types.Types[types.TINT])
c = defaultlit(c, types.Types[types.TINT])
if ir.IsConst(l, constant.Int) && l.Int64Val() < 0 {
if ir.IsConst(l, constant.Int) && ir.Int64Val(l) < 0 {
base.Fatalf("len for OSLICEHEADER must be non-negative")
}
if ir.IsConst(c, constant.Int) && c.Int64Val() < 0 {
if ir.IsConst(c, constant.Int) && ir.Int64Val(c) < 0 {
base.Fatalf("cap for OSLICEHEADER must be non-negative")
}
@ -2173,8 +2173,8 @@ func checksliceindex(l ir.Node, r ir.Node, tp *types.Type) bool {
} else if tp != nil && tp.NumElem() >= 0 && constant.Compare(x, token.GTR, constant.MakeInt64(tp.NumElem())) {
base.Errorf("invalid slice index %v (out of bounds for %d-element array)", r, tp.NumElem())
return false
} else if ir.IsConst(l, constant.String) && constant.Compare(x, token.GTR, constant.MakeInt64(int64(len(l.StringVal())))) {
base.Errorf("invalid slice index %v (out of bounds for %d-byte string)", r, len(l.StringVal()))
} else if ir.IsConst(l, constant.String) && constant.Compare(x, token.GTR, constant.MakeInt64(int64(len(ir.StringVal(l))))) {
base.Errorf("invalid slice index %v (out of bounds for %d-byte string)", r, len(ir.StringVal(l)))
return false
} else if doesoverflow(x, types.Types[types.TINT]) {
base.Errorf("invalid slice index %v (index too large)", r)
@ -3407,7 +3407,7 @@ func stringtoruneslit(n ir.Node) ir.Node {
var l []ir.Node
i := 0
for _, r := range n.Left().StringVal() {
for _, r := range ir.StringVal(n.Left()) {
l = append(l, ir.Nod(ir.OKEY, nodintconst(int64(i)), nodintconst(int64(r))))
i++
}
@ -3803,7 +3803,7 @@ func deadcode(fn *ir.Func) {
return
}
case ir.OFOR:
if !ir.IsConst(n.Left(), constant.Bool) || n.Left().BoolVal() {
if !ir.IsConst(n.Left(), constant.Bool) || ir.BoolVal(n.Left()) {
return
}
default:
@ -3833,7 +3833,7 @@ func deadcodeslice(nn *ir.Nodes) {
n.SetLeft(deadcodeexpr(n.Left()))
if ir.IsConst(n.Left(), constant.Bool) {
var body ir.Nodes
if n.Left().BoolVal() {
if ir.BoolVal(n.Left()) {
n.SetRlist(ir.Nodes{})
body = n.Body()
} else {
@ -3876,7 +3876,7 @@ func deadcodeexpr(n ir.Node) ir.Node {
n.SetLeft(deadcodeexpr(n.Left()))
n.SetRight(deadcodeexpr(n.Right()))
if ir.IsConst(n.Left(), constant.Bool) {
if n.Left().BoolVal() {
if ir.BoolVal(n.Left()) {
return n.Right() // true && x => x
} else {
return n.Left() // false && x => false
@ -3886,7 +3886,7 @@ func deadcodeexpr(n ir.Node) ir.Node {
n.SetLeft(deadcodeexpr(n.Left()))
n.SetRight(deadcodeexpr(n.Right()))
if ir.IsConst(n.Left(), constant.Bool) {
if n.Left().BoolVal() {
if ir.BoolVal(n.Left()) {
return n.Left() // true || x => true
} else {
return n.Right() // false || x => x

View File

@ -1014,7 +1014,7 @@ opswitch:
// The SSA backend will handle those.
switch et {
case types.TINT64:
c := n.Right().Int64Val()
c := ir.Int64Val(n.Right())
if c < 0 {
c = -c
}
@ -1022,7 +1022,7 @@ opswitch:
break opswitch
}
case types.TUINT64:
c := n.Right().Uint64Val()
c := ir.Uint64Val(n.Right())
if c < 1<<16 {
break opswitch
}
@ -1072,7 +1072,7 @@ opswitch:
base.Errorf("index out of bounds")
}
} else if ir.IsConst(n.Left(), constant.String) {
n.SetBounded(bounded(r, int64(len(n.Left().StringVal()))))
n.SetBounded(bounded(r, int64(len(ir.StringVal(n.Left())))))
if base.Flag.LowerM != 0 && n.Bounded() && !ir.IsConst(n.Right(), constant.Int) {
base.Warn("index bounds check elided")
}
@ -1507,7 +1507,7 @@ opswitch:
case ir.OSTR2BYTES:
s := n.Left()
if ir.IsConst(s, constant.String) {
sc := s.StringVal()
sc := ir.StringVal(s)
// Allocate a [n]byte of the right size.
t := types.NewArray(types.Types[types.TUINT8], int64(len(sc)))
@ -1936,7 +1936,7 @@ func walkprint(nn ir.Node, init *ir.Nodes) ir.Node {
for i := 0; i < len(s); {
var strs []string
for i < len(s) && ir.IsConst(s[i], constant.String) {
strs = append(strs, s[i].StringVal())
strs = append(strs, ir.StringVal(s[i]))
i++
}
if len(strs) > 0 {
@ -2016,7 +2016,7 @@ func walkprint(nn ir.Node, init *ir.Nodes) ir.Node {
case types.TSTRING:
cs := ""
if ir.IsConst(n, constant.String) {
cs = n.StringVal()
cs = ir.StringVal(n)
}
switch cs {
case " ":
@ -2673,7 +2673,7 @@ func addstr(n ir.Node, init *ir.Nodes) ir.Node {
sz := int64(0)
for _, n1 := range n.List().Slice() {
if n1.Op() == ir.OLITERAL {
sz += int64(len(n1.StringVal()))
sz += int64(len(ir.StringVal(n1)))
}
}
@ -3467,7 +3467,7 @@ func walkcompare(n ir.Node, init *ir.Nodes) ir.Node {
func tracecmpArg(n ir.Node, t *types.Type, init *ir.Nodes) ir.Node {
// Ugly hack to avoid "constant -1 overflows uintptr" errors, etc.
if n.Op() == ir.OLITERAL && n.Type().IsSigned() && n.Int64Val() < 0 {
if n.Op() == ir.OLITERAL && n.Type().IsSigned() && ir.Int64Val(n) < 0 {
n = copyexpr(n, n.Type(), init)
}
@ -3537,7 +3537,7 @@ func walkcompareString(n ir.Node, init *ir.Nodes) ir.Node {
// Length-only checks are ok, though.
maxRewriteLen = 0
}
if s := cs.StringVal(); len(s) <= maxRewriteLen {
if s := ir.StringVal(cs); len(s) <= maxRewriteLen {
if len(s) > 0 {
ncs = safeexpr(ncs, init)
}
@ -3632,7 +3632,7 @@ func bounded(n ir.Node, max int64) bool {
bits := int32(8 * n.Type().Width)
if smallintconst(n) {
v := n.Int64Val()
v := ir.Int64Val(n)
return 0 <= v && v < max
}
@ -3641,9 +3641,9 @@ func bounded(n ir.Node, max int64) bool {
v := int64(-1)
switch {
case smallintconst(n.Left()):
v = n.Left().Int64Val()
v = ir.Int64Val(n.Left())
case smallintconst(n.Right()):
v = n.Right().Int64Val()
v = ir.Int64Val(n.Right())
if n.Op() == ir.OANDNOT {
v = ^v
if !sign {
@ -3657,7 +3657,7 @@ func bounded(n ir.Node, max int64) bool {
case ir.OMOD:
if !sign && smallintconst(n.Right()) {
v := n.Right().Int64Val()
v := ir.Int64Val(n.Right())
if 0 <= v && v <= max {
return true
}
@ -3665,7 +3665,7 @@ func bounded(n ir.Node, max int64) bool {
case ir.ODIV:
if !sign && smallintconst(n.Right()) {
v := n.Right().Int64Val()
v := ir.Int64Val(n.Right())
for bits > 0 && v >= 2 {
bits--
v >>= 1
@ -3674,7 +3674,7 @@ func bounded(n ir.Node, max int64) bool {
case ir.ORSH:
if !sign && smallintconst(n.Right()) {
v := n.Right().Int64Val()
v := ir.Int64Val(n.Right())
if v > int64(bits) {
return true
}

View File

@ -296,62 +296,6 @@ func (n *Name) SetVal(v constant.Value) {
n.val = v
}
// Int64Val returns n as an int64.
// n must be an integer or rune constant.
func (n *Name) Int64Val() int64 {
if !IsConst(n, constant.Int) {
base.Fatalf("Int64Val(%v)", n)
}
x, ok := constant.Int64Val(n.Val())
if !ok {
base.Fatalf("Int64Val(%v)", n)
}
return x
}
// CanInt64 reports whether it is safe to call Int64Val() on n.
func (n *Name) CanInt64() bool {
if !IsConst(n, constant.Int) {
return false
}
// if the value inside n cannot be represented as an int64, the
// return value of Int64 is undefined
_, ok := constant.Int64Val(n.Val())
return ok
}
// Uint64Val returns n as an uint64.
// n must be an integer or rune constant.
func (n *Name) Uint64Val() uint64 {
if !IsConst(n, constant.Int) {
base.Fatalf("Uint64Val(%v)", n)
}
x, ok := constant.Uint64Val(n.Val())
if !ok {
base.Fatalf("Uint64Val(%v)", n)
}
return x
}
// BoolVal returns n as a bool.
// n must be a boolean constant.
func (n *Name) BoolVal() bool {
if !IsConst(n, constant.Bool) {
base.Fatalf("BoolVal(%v)", n)
}
return constant.BoolVal(n.Val())
}
// StringVal returns the value of a literal string Node as a string.
// n must be a string constant.
func (n *Name) StringVal() string {
if !IsConst(n, constant.String) {
base.Fatalf("StringVal(%v)", n)
}
return constant.StringVal(n.Val())
}
// The Class of a variable/function describes the "storage class"
// of a variable or function. During parsing, storage classes are
// called declaration contexts.

View File

@ -87,11 +87,6 @@ type Node interface {
MarkReadonly()
Val() constant.Value
SetVal(v constant.Value)
Int64Val() int64
Uint64Val() uint64
CanInt64() bool
BoolVal() bool
StringVal() string
// Storage for analysis passes.
Esc() uint16

View File

@ -32,7 +32,7 @@ func ConstValue(n Node) interface{} {
case constant.String:
return constant.StringVal(v)
case constant.Int:
return Int64Val(n.Type(), v)
return IntVal(n.Type(), v)
case constant.Float:
return Float64Val(v)
case constant.Complex:
@ -42,7 +42,7 @@ func ConstValue(n Node) interface{} {
// int64Val returns v converted to int64.
// Note: if t is uint64, very large values will be converted to negative int64.
func Int64Val(t *types.Type, v constant.Value) int64 {
func IntVal(t *types.Type, v constant.Value) int64 {
if t.IsUnsigned() {
if x, ok := constant.Uint64Val(v); ok {
return int64(x)
@ -118,3 +118,59 @@ func idealType(ct constant.Kind) *types.Type {
}
var OKForConst [types.NTYPE]bool
// CanInt64 reports whether it is safe to call Int64Val() on n.
func CanInt64(n Node) bool {
if !IsConst(n, constant.Int) {
return false
}
// if the value inside n cannot be represented as an int64, the
// return value of Int64 is undefined
_, ok := constant.Int64Val(n.Val())
return ok
}
// Int64Val returns n as an int64.
// n must be an integer or rune constant.
func Int64Val(n Node) int64 {
if !IsConst(n, constant.Int) {
base.Fatalf("Int64Val(%v)", n)
}
x, ok := constant.Int64Val(n.Val())
if !ok {
base.Fatalf("Int64Val(%v)", n)
}
return x
}
// Uint64Val returns n as an uint64.
// n must be an integer or rune constant.
func Uint64Val(n Node) uint64 {
if !IsConst(n, constant.Int) {
base.Fatalf("Uint64Val(%v)", n)
}
x, ok := constant.Uint64Val(n.Val())
if !ok {
base.Fatalf("Uint64Val(%v)", n)
}
return x
}
// BoolVal returns n as a bool.
// n must be a boolean constant.
func BoolVal(n Node) bool {
if !IsConst(n, constant.Bool) {
base.Fatalf("BoolVal(%v)", n)
}
return constant.BoolVal(n.Val())
}
// StringVal returns the value of a literal string Node as a string.
// n must be a string constant.
func StringVal(n Node) string {
if !IsConst(n, constant.String) {
base.Fatalf("StringVal(%v)", n)
}
return constant.StringVal(n.Val())
}