[wasm][debug] Test instrumentation breakpoints w/o start function

Add a test for a module without a start function; in that case, we want
to break when first calling into the module (via an exported function).

R=bmeurer@chromium.org

Bug: chromium:1151211
Change-Id: Id14978b5feff4dcd64cff828951f2a00b73c9736
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2763880Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73440}

test/inspector/debugger/wasm-instrumentation-breakpoint-expected.txt

@@ -35,3 +35,21 @@ Paused at v8://test/instantiate with reason "instrumentation".
 Paused at wasm://wasm/20da547a with reason "instrumentation".
 Script wasm://wasm/20da547a byte offset 26: Wasm opcode 0x01 (kExprNop)
 Done.
+
+Running test: testBreakInExportedFunction
+Setting instrumentation breakpoint
+{
+    id : <messageId>
+    result : {
+        breakpointId : <breakpointId>
+    }
+}
+Instantiating wasm module.
+Paused at v8://test/instantiate with reason "instrumentation".
+Calling exported function 'func' (should trigger a breakpoint).
+Paused at v8://test/call_func with reason "instrumentation".
+Paused at wasm://wasm/8c388106 with reason "instrumentation".
+Script wasm://wasm/8c388106 byte offset 33: Wasm opcode 0x01 (kExprNop)
+Calling exported function 'func' a second time (should trigger no breakpoint).
+Paused at v8://test/call_func with reason "instrumentation".
+Done.

test/inspector/debugger/wasm-instrumentation-breakpoint.js

@@ -19,7 +19,6 @@ Protocol.Debugger.onPaused(async msg => {
 });
 
 // TODO(clemensb): Add test for 'beforeScriptWithSourceMapExecution'.
-// TODO(clemensb): Add test for module without start function.
 
 InspectorTest.runAsyncTestSuite([
   async function testBreakInStartFunction() {
@@ -64,5 +63,29 @@ InspectorTest.runAsyncTestSuite([
     await WasmInspectorTest.instantiate(builder.toArray());
     InspectorTest.log('Done.');
     await Protocol.Debugger.disable();
-  }
+  },
+
+  async function testBreakInExportedFunction() {
+    const builder = new WasmModuleBuilder();
+    const func =
+        builder.addFunction('func', kSig_v_v).addBody([kExprNop]).exportFunc();
+
+    await Protocol.Debugger.enable();
+    InspectorTest.log('Setting instrumentation breakpoint');
+    InspectorTest.logMessage(
+        await Protocol.Debugger.setInstrumentationBreakpoint(
+            {instrumentation: 'beforeScriptExecution'}));
+    InspectorTest.log('Instantiating wasm module.');
+    await WasmInspectorTest.instantiate(builder.toArray());
+    InspectorTest.log(
+        'Calling exported function \'func\' (should trigger a breakpoint).');
+    await WasmInspectorTest.evalWithUrl('instance.exports.func()', 'call_func');
+    InspectorTest.log(
+        'Calling exported function \'func\' a second time ' +
+        '(should trigger no breakpoint).');
+    await WasmInspectorTest.evalWithUrl('instance.exports.func()', 'call_func');
+    InspectorTest.log('Done.');
+    await Protocol.Debugger.disable();
+  },
+
 ]);