[Strings] Initial string execution support (#5491)

Store string data as GC data. Inefficient (one Const per char), but ok for now.

Implement string.new_wtf16 and string.const, enough for basic testing.

Create strings in makeConstantExpression, which enables ctor-eval support.

Print strings in fuzz-exec which makes testing easier.

1 files changed, 36 insertions, 0 deletions

diff --git a/test/lit/exec/strings.wast b/test/lit/exec/strings.wast
new file mode 100644
index 000000000..2852337c8
--- /dev/null
+++ b/test/lit/exec/strings.wast
@@ -0,0 +1,36 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py --output=fuzz-exec and should not be edited.
+
+;; RUN: wasm-opt %s -all --fuzz-exec -q -o /dev/null 2>&1 | filecheck %s
+
+(module
+  (type $array16 (array (mut i16)))
+
+  ;; CHECK:      [fuzz-exec] calling new_wtf16_array
+  ;; CHECK-NEXT: [fuzz-exec] note result: new_wtf16_array => string("ello")
+  (func "new_wtf16_array" (result stringref)
+    (string.new_wtf16_array
+      (array.init_static $array16
+        (i32.const 104) ;; h
+        (i32.const 101) ;; e
+        (i32.const 108) ;; l
+        (i32.const 108) ;; l
+        (i32.const 111) ;; o
+      )
+      (i32.const 1) ;; start from index 1, to chop off the 'h'
+      (i32.const 5)
+    )
+  )
+
+  ;; CHECK:      [fuzz-exec] calling const
+  ;; CHECK-NEXT: [fuzz-exec] note result: const => string("world")
+  (func "const" (result stringref)
+    (string.const "world")
+  )
+)
+;; CHECK:      [fuzz-exec] calling new_wtf16_array
+;; CHECK-NEXT: [fuzz-exec] note result: new_wtf16_array => string("ello")
+
+;; CHECK:      [fuzz-exec] calling const
+;; CHECK-NEXT: [fuzz-exec] note result: const => string("world")
+;; CHECK-NEXT: [fuzz-exec] comparing const
+;; CHECK-NEXT: [fuzz-exec] comparing new_wtf16_array