Implement `array` basic heap type (#5148)

`array` is the supertype of all defined array types and for now is a subtype of
`data`. (Once `data` becomes `struct` this will no longer be true.) Update the
binary and text parsing of `array.len` to ignore the obsolete type annotation
and update the binary emitting to emit a zero in place of the old type
annotation and the text printing to print an arbitrary heap type for the
annotation. A follow-on PR will add support for the newer unannotated version of
`array.len`.

1 files changed, 72 insertions, 0 deletions

diff --git a/test/lit/arrays.wast b/test/lit/arrays.wast
new file mode 100644
index 000000000..b79ca1844
--- /dev/null
+++ b/test/lit/arrays.wast
@@ -0,0 +1,72 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --all-items and should not be edited.
+
+;; Check that array types and operations are emitted properly in the binary format.
+
+;; RUN: wasm-opt %s -all -S -o - | filecheck %s
+;; RUN: wasm-opt %s -all --roundtrip -S -o - | filecheck %s --check-prefix=ROUNDTRIP
+
+;; Check that we can roundtrip through the text format as well.
+
+;; RUN: wasm-opt %s -all -S -o - | wasm-opt -all -S -o - | filecheck %s
+
+(module
+ (type $byte-array (array (mut i8)))
+ ;; CHECK:      (type $ref|array|_=>_i32 (func (param (ref array)) (result i32)))
+
+ ;; CHECK:      (type $nullref_=>_i32 (func (param nullref) (result i32)))
+
+ ;; CHECK:      (type $arrayref_=>_i32 (func (param arrayref) (result i32)))
+
+ ;; CHECK:      (func $len (param $a (ref array)) (result i32)
+ ;; CHECK-NEXT:  (array.len array
+ ;; CHECK-NEXT:   (local.get $a)
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ ;; ROUNDTRIP:      (type $ref|array|_=>_i32 (func (param (ref array)) (result i32)))
+
+ ;; ROUNDTRIP:      (type $nullref_=>_i32 (func (param nullref) (result i32)))
+
+ ;; ROUNDTRIP:      (type $arrayref_=>_i32 (func (param arrayref) (result i32)))
+
+ ;; ROUNDTRIP:      (func $len (param $a (ref array)) (result i32)
+ ;; ROUNDTRIP-NEXT:  (array.len array
+ ;; ROUNDTRIP-NEXT:   (local.get $a)
+ ;; ROUNDTRIP-NEXT:  )
+ ;; ROUNDTRIP-NEXT: )
+ (func $len (param $a (ref array)) (result i32)
+  ;; TODO: remove the unused type annotation
+  (array.len $byte-array
+   (local.get $a)
+  )
+ )
+
+ ;; CHECK:      (func $impossible-len (param $none nullref) (result i32)
+ ;; CHECK-NEXT:  (array.len none
+ ;; CHECK-NEXT:   (local.get $none)
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ ;; ROUNDTRIP:      (func $impossible-len (param $none nullref) (result i32)
+ ;; ROUNDTRIP-NEXT:  (array.len none
+ ;; ROUNDTRIP-NEXT:   (local.get $none)
+ ;; ROUNDTRIP-NEXT:  )
+ ;; ROUNDTRIP-NEXT: )
+ (func $impossible-len (param $none nullref) (result i32)
+  (array.len $byte-array
+   (local.get $none)
+  )
+ )
+
+ ;; CHECK:      (func $unreachable-len (param $a arrayref) (result i32)
+ ;; CHECK-NEXT:  (array.len array
+ ;; CHECK-NEXT:   (unreachable)
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ ;; ROUNDTRIP:      (func $unreachable-len (param $a arrayref) (result i32)
+ ;; ROUNDTRIP-NEXT:  (unreachable)
+ ;; ROUNDTRIP-NEXT: )
+ (func $unreachable-len (param $a arrayref) (result i32)
+  (array.len $byte-array
+   (unreachable)
+  )
+ )
+)