diff options
Diffstat (limited to 'src/cmd/compile/internal/noder/helpers.go')
-rw-r--r-- | src/cmd/compile/internal/noder/helpers.go | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/src/cmd/compile/internal/noder/helpers.go b/src/cmd/compile/internal/noder/helpers.go index 33acd6051a..40f80ab528 100644 --- a/src/cmd/compile/internal/noder/helpers.go +++ b/src/cmd/compile/internal/noder/helpers.go @@ -11,6 +11,7 @@ import ( "cmd/compile/internal/ir" "cmd/compile/internal/typecheck" "cmd/compile/internal/types" + "cmd/compile/internal/types2" "cmd/internal/src" ) @@ -39,10 +40,6 @@ func typed(typ *types.Type, n ir.Node) ir.Node { // Values -func Const(pos src.XPos, typ *types.Type, val constant.Value) ir.Node { - return typed(typ, ir.NewBasicLit(pos, val)) -} - func OrigConst(pos src.XPos, typ *types.Type, val constant.Value, op ir.Op, raw string) ir.Node { orig := ir.NewRawOrigExpr(pos, op, raw) return ir.NewConstExpr(val, typed(typ, orig)) @@ -224,3 +221,33 @@ func IncDec(pos src.XPos, op ir.Op, x ir.Node) *ir.AssignOpStmt { } return ir.NewAssignOpStmt(pos, op, x, bl) } + +func idealType(tv types2.TypeAndValue) types2.Type { + // The gc backend expects all expressions to have a concrete type, and + // types2 mostly satisfies this expectation already. But there are a few + // cases where the Go spec doesn't require converting to concrete type, + // and so types2 leaves them untyped. So we need to fix those up here. + typ := tv.Type + if basic, ok := typ.(*types2.Basic); ok && basic.Info()&types2.IsUntyped != 0 { + switch basic.Kind() { + case types2.UntypedNil: + // ok; can appear in type switch case clauses + // TODO(mdempsky): Handle as part of type switches instead? + case types2.UntypedInt, types2.UntypedFloat, types2.UntypedComplex: + // Untyped rhs of non-constant shift, e.g. x << 1.0. + // If we have a constant value, it must be an int >= 0. + if tv.Value != nil { + s := constant.ToInt(tv.Value) + assert(s.Kind() == constant.Int && constant.Sign(s) >= 0) + } + typ = types2.Typ[types2.Uint] + case types2.UntypedBool: + typ = types2.Typ[types2.Bool] // expression in "if" or "for" condition + case types2.UntypedString: + typ = types2.Typ[types2.String] // argument to "append" or "copy" calls + default: + return nil + } + } + return typ +} |