OptimizeInstructions on memory.copy: check size for side effect as well (#3072)

Fix issue found by fuzzer: #3038 (comment)

Author: MaxGraey

src/passes/OptimizeInstructions.cpp

@@ -1404,6 +1404,8 @@ struct OptimizeInstructions
     // memory.copy(x, x, sz)  ==>  nop
     if (!EffectAnalyzer(getPassOptions(), features, memCopy->dest)
            .hasSideEffects() &&
+        !EffectAnalyzer(getPassOptions(), features, memCopy->size)
+           .hasSideEffects() &&
         ExpressionAnalyzer::equal(memCopy->dest, memCopy->source)) {
       return ExpressionManipulator::nop(memCopy);
     }

test/passes/optimize-instructions_all-features.txt

@@ -3793,6 +3793,13 @@
    (local.get $src)
    (local.get $sz)
   )
+  (memory.copy
+   (i32.const 0)
+   (i32.const 0)
+   (i32.load
+    (i32.const 3)
+   )
+  )
  )
 )
 (module

test/passes/optimize-instructions_all-features.wast

@@ -4294,7 +4294,7 @@
       (i32.const 8)
     )
 
-     (memory.copy
+    (memory.copy
       (local.get $dst)
       (local.get $src)
       (i32.const 16)
@@ -4305,6 +4305,14 @@
       (local.get $src)
       (local.get $sz)
     )
+
+    (memory.copy  ;; skip
+      (i32.const 0)
+      (i32.const 0)
+      (i32.load
+        (i32.const 3) ;; side effect
+      )
+    )
   )
 )
 (module