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

thibaudmichaud · V8 LUCI CQ · commit ca1a2cfb391b · 2021-05-31T11:58:46.000Z
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/+/2928499 Reviewed-by: Andreas Haas <ahaas@chromium.org> Commit-Queue: Thibaud Michaud <thibaudm@chromium.org> Cr-Commit-Position: refs/heads/master@{#74855}
diff --git a/test/cctest/wasm/test-run-wasm-exceptions.cc b/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
diff --git a/test/common/wasm/wasm-interpreter.cc b/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);
             }

Original file line number	Diff line number	Diff line change
`@@ -1005,7 +1005,7 @@ class SideTable : public ZoneObject {`
`1005`	`1005`	`Control* target = &control_stack[max_depth - imm.depth];`
`1006`	`1006`	`DCHECK_EQ(*target->pc, kExprTry);`
`1007`	`1007`	`DCHECK_NOT_NULL(target->else_label);`
`1008`		`- if (!unreachable) {`
	`1008`	`+ if (!control_parent().unreachable) {`
`1009`	`1009`	`target->else_label->Ref(i.pc(),`
`1010`	`1010`	`c->end_label->target_stack_height);`
`1011`	`1011`	`}`