[wasm] Allocate a single script per wasm module

test/mjsunit/wasm/debug-disassembly.js

-// 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.
-
-// Flags: --expose-wasm --expose-debug-as debug
-
-load("test/mjsunit/wasm/wasm-constants.js");
-load("test/mjsunit/wasm/wasm-module-builder.js");
-
-Debug = debug.Debug
-
-// Initialized in setup().
-var exception;
-var break_count;
-var num_wasm_scripts;
-var module;
-
-function listener(event, exec_state, event_data, data) {
-  try {
-    if (event == Debug.DebugEvent.Break) {
-      ++break_count;
-      // Request frame details. This should trigger creation of the Script
-      // objects for all frames on the stack.
-      var num_frames = exec_state.frameCount();
-      for (var i = 0; i < num_frames; ++i) {
-        var frame = exec_state.frame(i);
-        var details = frame.details();
-        var script = details.script();
-        if (script.type == Debug.ScriptType.Wasm) {
-          var pos = frame.sourcePosition();
-          var name = script.nameOrSourceURL();
-          var disassembly = Debug.disassembleWasmFunction(script.id);
-          var offset_table = Debug.getWasmFunctionOffsetTable(script.id);
-          assertEquals(0, offset_table.length % 3);
-          var lineNr = null;
-          var columnNr = null;
-          for (var p = 0; p < offset_table.length; p += 3) {
-            if (offset_table[p] != pos) continue;
-            lineNr = offset_table[p+1];
-            columnNr = offset_table[p+2];
-          }
-          assertNotNull(lineNr, "position should occur in offset table");
-          assertNotNull(columnNr, "position should occur in offset table");
-          var line = disassembly.split("\n")[lineNr];
-          assertTrue(!!line, "line number must occur in disassembly");
-          assertTrue(line.length > columnNr, "column number must be valid");
-          var expected_string;
-          if (name.endsWith("/1")) {
-            // Function 0 calls the imported function.
-            expected_string = "kExprCallFunction,";
-          } else if (name.endsWith("/2")) {
-            // Function 1 calls function 0.
-            expected_string = "kExprCallFunction,";
-          } else {
-            assertTrue(false, "Unexpected wasm script: " + name);
-          }
-          assertTrue(line.substr(columnNr).startsWith(expected_string),
-              "offset " + columnNr + " should start with '" + expected_string
-              + "': " + line);
-        }
-      }
-    } else if (event == Debug.DebugEvent.AfterCompile) {
-      var script = event_data.script();
-      if (script.scriptType() == Debug.ScriptType.Wasm) {
-        ++num_wasm_scripts;
-      }
-    }
-  } catch (e) {
-    print("exception: " + e);
-    exception = e;
-  }
-};
-
-var builder = new WasmModuleBuilder();
-
-builder.addImport("func", kSig_v_v);
-
-builder.addFunction("call_import", kSig_v_v)
-  .addBody([kExprCallFunction, 0])
-  .exportFunc();
-
-// Add a bit of unneccessary code to increase the byte offset.
-builder.addFunction("call_call_import", kSig_v_v)
-  .addLocals({i32_count: 2})
-  .addBody([
-      kExprI32Const, 27, kExprSetLocal, 0,
-      kExprI32Const, (-7 & 0x7f), kExprSetLocal, 1,
-        kExprGetLocal, 0, kExprGetLocal, 1, kExprI32Add, kExprI64UConvertI32,
-        kExprI64Const, 0,
-      kExprI64Ne, kExprIf, kAstStmt,
-        kExprCallFunction, 1,
-      kExprEnd
-  ])
-  .exportFunc();
-
-function call_debugger() {
-  debugger;
-}
-
-function setup() {
-  module = builder.instantiate({func: call_debugger});
-  exception = null;
-  break_count = 0;
-  num_wasm_scripts = 0;
-}
-
-(function testRegisteredWasmScripts1() {
-  setup();
-  Debug.setListener(listener);
-  // Call the "call_import" function -> 1 script.
-  module.exports.call_import();
-  module.exports.call_import();
-  module.exports.call_call_import();
-  Debug.setListener(null);
-
-  assertEquals(3, break_count);
-  if (exception) throw exception;
-})();
-
-(function testRegisteredWasmScripts2() {
-  setup();
-  Debug.setListener(listener);
-  module.exports.call_call_import();
-  Debug.setListener(null);
-
-  assertEquals(1, break_count);
-  if (exception) throw exception;
-})();