[wasm][interpreter][eh] Fix unreachable ref

The delegate instruction is executed when an exception is thrown, not
after the last instruction of the block. Handle reachability
accordingly.

R=ahaas@chromium.org

Bug: chromium:1212396
Change-Id: I55e342cd73da44142cfbad7e16ab65ef513e6a60
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2928499Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74855}

test/cctest/wasm/test-run-wasm-exceptions.cc

@@ -699,6 +699,17 @@ TEST(Regress1197408) {
   CHECK_EQ(0, r.CallInterpreter(0, 0, 0));
 }
 
+TEST(Regress1212396) {
+  TestSignatures sigs;
+  EXPERIMENTAL_FLAG_SCOPE(eh);
+  WasmRunner<int32_t> r(TestExecutionTier::kInterpreter);
+  uint32_t except = r.builder().AddException(sigs.v_v());
+  BUILD(r, kExprTry, kVoidCode, kExprTry, kVoidCode, kExprI32Const, 0,
+        kExprThrow, except, kExprDelegate, 0, kExprCatch, except, kExprEnd,
+        kExprI32Const, 42);
+  CHECK_EQ(42, r.CallInterpreter());
+}
+
 }  // namespace test_run_wasm_exceptions
 }  // namespace wasm
 }  // namespace internal

test/common/wasm/wasm-interpreter.cc

@@ -1005,7 +1005,7 @@ class SideTable : public ZoneObject {
             Control* target = &control_stack[max_depth - imm.depth];
             DCHECK_EQ(*target->pc, kExprTry);
             DCHECK_NOT_NULL(target->else_label);
-            if (!unreachable) {
+            if (!control_parent().unreachable) {
               target->else_label->Ref(i.pc(),
                                       c->end_label->target_stack_height);
             }