[Wasm GC] Fix lack of packing in array.init (#4153)

3 files changed, 31 insertions, 1 deletions

diff --git a/src/wasm-interpreter.h b/src/wasm-interpreter.h
index 9fc11de76..8dd7859ac 100644
--- a/src/wasm-interpreter.h
+++ b/src/wasm-interpreter.h
@@ -1712,13 +1712,14 @@ public:
     if (num >= ArrayLimit) {
       hostLimit("allocation failure");
     }
+    auto field = curr->type.getHeapType().getArray().element;
     Literals data(num);
     for (Index i = 0; i < num; i++) {
       auto value = this->visit(curr->values[i]);
       if (value.breaking()) {
         return value;
       }
-      data[i] = value.getSingleValue();
+      data[i] = truncateForPacking(value.getSingleValue(), field);
     }
     return Flow(Literal(std::make_shared<GCData>(rtt.getSingleValue(), data),
                         curr->type));
diff --git a/test/passes/Oz_fuzz-exec_all-features.txt b/test/passes/Oz_fuzz-exec_all-features.txt
index 4ac373f75..1360d6b42 100644
--- a/test/passes/Oz_fuzz-exec_all-features.txt
+++ b/test/passes/Oz_fuzz-exec_all-features.txt
@@ -65,6 +65,8 @@
 [LoggingExternalInterface logging 2]
 [LoggingExternalInterface logging 42]
 [LoggingExternalInterface logging 50]
+[fuzz-exec] calling array.init-packed
+[LoggingExternalInterface logging 8]
 (module
  (type $extendedstruct (struct (field (mut i32)) (field f64)))
  (type $struct (struct (field (mut i32))))
@@ -95,6 +97,7 @@
  (export "array-copy" (func $20))
  (export "rtt_Fresh" (func $21))
  (export "array.init" (func $22))
+ (export "array.init-packed" (func $23))
  (func $0 (; has Stack IR ;)
   (local $0 i32)
   (call $log
@@ -487,6 +490,17 @@
    )
   )
  )
+ (func $23 (; has Stack IR ;)
+  (call $log
+   (array.get_u $bytes
+    (array.init $bytes
+     (i32.const -11512)
+     (rtt.canon $bytes)
+    )
+    (i32.const 0)
+   )
+  )
+ )
 )
 [fuzz-exec] calling structs
 [LoggingExternalInterface logging 0]
@@ -554,6 +568,8 @@
 [LoggingExternalInterface logging 2]
 [LoggingExternalInterface logging 42]
 [LoggingExternalInterface logging 50]
+[fuzz-exec] calling array.init-packed
+[LoggingExternalInterface logging 8]
 ignoring comparison of ExecutionResults!
 [fuzz-exec] calling foo
 [host limit allocation failure]
diff --git a/test/passes/Oz_fuzz-exec_all-features.wast b/test/passes/Oz_fuzz-exec_all-features.wast
index a41e2bf70..54d93c9d0 100644
--- a/test/passes/Oz_fuzz-exec_all-features.wast
+++ b/test/passes/Oz_fuzz-exec_all-features.wast
@@ -497,6 +497,19 @@
    (array.get_u $bytes (local.get $x) (i32.const 1))
   )
  )
+ (func "array.init-packed"
+  (local $x (ref null $bytes))
+  (local.set $x
+   (array.init $bytes
+    (i32.const -11512)
+    (rtt.canon $bytes)
+   )
+  )
+  ;; The value should be be -11512 & 255 => 8
+  (call $log
+   (array.get_u $bytes (local.get $x) (i32.const 0))
+  )
+ )
 )
 (module
  (type $[mut:i8] (array (mut i8)))