[wasm] Initial signal handler

test/cctest/wasm/test-wasm-trap-position.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "src/trap-handler/trap-handler.h"
 #include "src/wasm/wasm-macro-gen.h"
 
 #include "test/cctest/cctest.h"
 #include "test/cctest/compiler/value-helper.h"
 #include "test/cctest/wasm/wasm-run-utils.h"
 #include "test/common/wasm/test-signatures.h"
 
 using namespace v8::base;
 using namespace v8::internal;
 using namespace v8::internal::compiler;
@@ skipping 75 matching lines @@
   // Line and column are 1-based, so add 1 for the expected wasm output.
   ExceptionInfo expected_exceptions[] = {
       {"main", static_cast<int>(wasm_index) + 1, 2},  // --
       {"callFn", 1, 24}                               // --
   };
   CheckExceptionInfos(maybe_exc.ToHandleChecked(), expected_exceptions);
 }
 
 // Trigger a trap for loading from out-of-bounds.
 TEST(IllegalLoad) {
+  if (trap_handler::ShouldEnableTrapHandler()) {
+    // cctests don't register the handler data, so this test won't work

[ahaas, 2017/02/20 09:27:24]

Runtime calls don't work in cctests, so I guess you never set the flag that wasm
code is executed.

[Eric Holk, 2017/02/23 02:16:57]

Acknowledged.

+    // TODO(eholk): find out why and fix it.

[Mark Seaborn, 2017/02/17 21:41:12]

Does this need to get fixed?

[Eric Holk, 2017/02/23 02:16:57]

This test just does the basic out of bounds memory access test, which we have
covered in the mjsunit tests, and those do run. I think we should fix this, but
I'd rather do it in a followup CL.

I did realize the comment was a bit out of date. The immediate problem is that
r.module().AddMemory down below doesn't create the guard pages, so our signal
handler never runs. I've updated the comment here to reflect this.

+    return;
+  }
   WasmRunner<void> r(kExecuteCompiled);
   TestSignatures sigs;
   // Set the execution context, such that a runtime error can be thrown.
   r.SetModuleContext();
   r.module().AddMemory(0L);
 
   BUILD(r, WASM_IF(WASM_ONE, WASM_SEQ(WASM_LOAD_MEM(MachineType::Int32(),
                                                     WASM_I32V_1(-3)),
                                       WASM_DROP)));
   uint32_t wasm_index_1 = r.function()->func_index;
@@ skipping 21 matching lines @@
   CHECK(returnObjMaybe.is_null());
 
   // Line and column are 1-based, so add 1 for the expected wasm output.
   ExceptionInfo expected_exceptions[] = {
       {"main", static_cast<int>(wasm_index_1) + 1, 8},       // --
       {"call_main", static_cast<int>(wasm_index_2) + 1, 3},  // --
       {"callFn", 1, 24}                                      // --
   };
   CheckExceptionInfos(maybe_exc.ToHandleChecked(), expected_exceptions);
 }