[dev.regabi] cmd/compile/internal/types: add IsScalar query method

Add method Type.IsScalar() method, which returns TRUE
for numeric and pointer-shaped types, false for composites
such as string/array/slice/struct.

Change-Id: Ie53c71c07c5b3fbae11b48addd172343dc6bf3fd
Reviewed-on: https://go-review.googlesource.com/c/go/+/274857
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Than McIntosh <thanm@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/cmd/compile/internal/types/type.go b/src/cmd/compile/internal/types/type.go
index e968a799e3..4d1d30133c 100644
--- a/src/cmd/compile/internal/types/type.go
+++ b/src/cmd/compile/internal/types/type.go
@@ -1335,6 +1335,20 @@ func (t *Type) IsEmptyInterface() bool {
 	return t.IsInterface() && t.NumFields() == 0
 }
 
+// IsScalar reports whether 't' is a scalar Go type, e.g.
+// bool/int/float/complex. Note that struct and array types consisting
+// of a single scalar element are not considered scalar, likewise
+// pointer types are also not considered scalar.
+func (t *Type) IsScalar() bool {
+	switch t.kind {
+	case TBOOL, TINT8, TUINT8, TINT16, TUINT16, TINT32,
+		TUINT32, TINT64, TUINT64, TINT, TUINT,
+		TUINTPTR, TCOMPLEX64, TCOMPLEX128, TFLOAT32, TFLOAT64:
+		return true
+	}
+	return false
+}
+
 func (t *Type) PtrTo() *Type {
 	return NewPtr(t)
 }