[wasm] Block compile/instantiate of large array buffers

third_party/WebKit/LayoutTests/fast/wasm/wasm-module-builder.js

Index: third_party/WebKit/LayoutTests/fast/wasm/wasm-module-builder.js
diff --git a/third_party/WebKit/LayoutTests/fast/wasm/wasm-module-builder.js b/third_party/WebKit/LayoutTests/fast/wasm/wasm-module-builder.js
new file mode 100644
index 0000000000000000000000000000000000000000..0d8c698dac5e97b29b4ce06718cc23c9c2921914
--- /dev/null
+++ b/third_party/WebKit/LayoutTests/fast/wasm/wasm-module-builder.js
@@ -0,0 +1,581 @@
+// Copyright 2017 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.
+
+// Used for encoding f32 and double constants to bits.
+let __buffer = new ArrayBuffer(8);
+let byte_view = new Int8Array(__buffer);
+let f32_view = new Float32Array(__buffer);
+let f64_view = new Float64Array(__buffer);
+
+class Binary extends Array {
+  emit_u8(val) {
+    this.push(val);
+  }
+
+  emit_u16(val) {
+    this.push(val & 0xff);
+    this.push((val >> 8) & 0xff);
+  }
+
+  emit_u32(val) {
+    this.push(val & 0xff);
+    this.push((val >> 8) & 0xff);
+    this.push((val >> 16) & 0xff);
+    this.push((val >> 24) & 0xff);
+  }
+
+  emit_u32v(val) {
+    while (true) {
+      let v = val & 0xff;
+      val = val >>> 7;
+      if (val == 0) {
+        this.push(v);
+        break;
+      }
+      this.push(v | 0x80);
+    }
+  }
+
+  emit_bytes(data) {
+    for (let i = 0; i < data.length; i++) {
+      this.push(data[i] & 0xff);
+    }
+  }
+
+  emit_string(string) {
+    // When testing illegal names, we pass a byte array directly.
+    if (string instanceof Array) {
+      this.emit_u32v(string.length);
+      this.emit_bytes(string);
+      return;
+    }
+
+    // This is the hacky way to convert a JavaScript string to a UTF8 encoded
+    // string only containing single-byte characters.
+    let string_utf8 = unescape(encodeURIComponent(string));
+    this.emit_u32v(string_utf8.length);
+    for (let i = 0; i < string_utf8.length; i++) {
+      this.emit_u8(string_utf8.charCodeAt(i));
+    }
+  }
+
+  emit_header() {
+    this.push(kWasmH0, kWasmH1, kWasmH2, kWasmH3,
+              kWasmV0, kWasmV1, kWasmV2, kWasmV3);
+  }
+
+  emit_section(section_code, content_generator) {
+    // Emit section name.
+    this.emit_u8(section_code);
+    // Emit the section to a temporary buffer: its full length isn't know yet.
+    let section = new Binary;
+    content_generator(section);
+    // Emit section length.
+    this.emit_u32v(section.length);
+    // Copy the temporary buffer.
+    this.push(...section);
+  }
+}
+
+class WasmFunctionBuilder {
+  constructor(module, name, type_index) {
+    this.module = module;
+    this.name = name;
+    this.type_index = type_index;
+    this.body = [];
+  }
+
+  exportAs(name) {
+    this.module.addExport(name, this.index);
+    return this;
+  }
+
+  exportFunc() {
+    this.exportAs(this.name);
+    return this;
+  }
+
+  addBody(body) {
+    for (let b of body) {
+      if (typeof b != 'number') throw new Error("invalid body");
+    }
+    this.body = body;
+    // Automatically add the end for the function block to the body.
+    body.push(kExprEnd);
+    return this;
+  }
+
+  addBodyWithEnd(body) {
+    this.body = body;
+    return this;
+  }
+
+  addLocals(locals) {
+    this.locals = locals;
+    return this;
+  }
+
+  end() {
+    return this.module;
+  }
+}
+
+class WasmGlobalBuilder {
+  constructor(module, type, mutable) {
+    this.module = module;
+    this.type = type;
+    this.mutable = mutable;
+    this.init = 0;
+  }
+
+  exportAs(name) {
+    this.module.exports.push({name: name, kind: kExternalGlobal,
+                              index: this.index});
+    return this;
+  }
+}
+
+class WasmModuleBuilder {
+  constructor() {
+    this.types = [];
+    this.imports = [];
+    this.exports = [];
+    this.globals = [];
+    this.functions = [];
+    this.function_table = [];
+    this.function_table_length = 0;
+    this.function_table_inits = [];
+    this.segments = [];
+    this.explicit = [];
+    this.num_imported_funcs = 0;
+    this.num_imported_globals = 0;
+    return this;
+  }
+
+  addStart(start_index) {
+    this.start_index = start_index;
+    return this;
+  }
+
+  addMemory(min, max, exp) {
+    this.memory = {min: min, max: max, exp: exp};
+    return this;
+  }
+
+  addExplicitSection(bytes) {
+    this.explicit.push(bytes);
+    return this;
+  }
+
+  stringToBytes(name) {
+    var result = new Binary();
+    result.emit_u32v(name.length);
+    for (var i = 0; i < name.length; i++) {
+      result.emit_u8(name.charCodeAt(i));
+    }
+    return result;
+  }
+
+  addCustomSection(name, bytes) {
+    name = this.stringToBytes(name);
+    var length = new Binary();
+    length.emit_u32v(name.length + bytes.length);
+    this.explicit.push([0, ...length, ...name, ...bytes]);
+  }
+
+  addType(type) {
+    // TODO: canonicalize types?
+    this.types.push(type);
+    return this.types.length - 1;
+  }
+
+  addGlobal(local_type, mutable) {
+    let glob = new WasmGlobalBuilder(this, local_type, mutable);
+    glob.index = this.globals.length + this.num_imported_globals;
+    this.globals.push(glob);
+    return glob;
+  }
+
+  addFunction(name, type) {
+    let type_index = (typeof type) == "number" ? type : this.addType(type);
+    let func = new WasmFunctionBuilder(this, name, type_index);
+    func.index = this.functions.length + this.num_imported_funcs;
+    this.functions.push(func);
+    return func;
+  }
+
+  addImport(module = "", name, type) {
+    let type_index = (typeof type) == "number" ? type : this.addType(type);
+    this.imports.push({module: module, name: name, kind: kExternalFunction,
+                       type: type_index});
+    return this.num_imported_funcs++;
+  }
+
+  addImportedGlobal(module = "", name, type) {
+    let o = {module: module, name: name, kind: kExternalGlobal, type: type,
+             mutable: false}
+    this.imports.push(o);
+    return this.num_imported_globals++;
+  }
+
+  addImportedMemory(module = "", name, initial = 0, maximum) {
+    let o = {module: module, name: name, kind: kExternalMemory,
+             initial: initial, maximum: maximum};
+    this.imports.push(o);
+    return this;
+  }
+
+  addImportedTable(module = "", name, initial, maximum) {
+    let o = {module: module, name: name, kind: kExternalTable, initial: initial,
+             maximum: maximum};
+    this.imports.push(o);
+  }
+
+  addExport(name, index) {
+    this.exports.push({name: name, kind: kExternalFunction, index: index});
+    return this;
+  }
+
+  addExportOfKind(name, kind, index) {
+    this.exports.push({name: name, kind: kind, index: index});
+    return this;
+  }
+
+  addDataSegment(addr, data, is_global = false) {
+    this.segments.push({addr: addr, data: data, is_global: is_global});
+    return this.segments.length - 1;
+  }
+
+  exportMemoryAs(name) {
+    this.exports.push({name: name, kind: kExternalMemory, index: 0});
+  }
+
+  addFunctionTableInit(base, is_global, array, is_import = false) {
+    this.function_table_inits.push({base: base, is_global: is_global,
+                                    array: array});
+    if (!is_global) {
+      var length = base + array.length;
+      if (length > this.function_table_length && !is_import) {
+        this.function_table_length = length;
+      }
+    }
+    return this;
+  }
+
+  appendToTable(array) {
+    return this.addFunctionTableInit(this.function_table.length, false, array);
+  }
+
+  setFunctionTableLength(length) {
+    this.function_table_length = length;
+    return this;
+  }
+
+  toArray(debug = false) {
+    let binary = new Binary;
+    let wasm = this;
+
+    // Add header
+    binary.emit_header();
+
+    // Add type section
+    if (wasm.types.length > 0) {
+      if (debug) print("emitting types @ " + binary.length);
+      binary.emit_section(kTypeSectionCode, section => {
+        section.emit_u32v(wasm.types.length);
+        for (let type of wasm.types) {
+          section.emit_u8(kWasmFunctionTypeForm);
+          section.emit_u32v(type.params.length);
+          for (let param of type.params) {
+            section.emit_u8(param);
+          }
+          section.emit_u32v(type.results.length);
+          for (let result of type.results) {
+            section.emit_u8(result);
+          }
+        }
+      });
+    }
+
+    // Add imports section
+    if (wasm.imports.length > 0) {
+      if (debug) print("emitting imports @ " + binary.length);
+      binary.emit_section(kImportSectionCode, section => {
+        section.emit_u32v(wasm.imports.length);
+        for (let imp of wasm.imports) {
+          section.emit_string(imp.module);
+          section.emit_string(imp.name || '');
+          section.emit_u8(imp.kind);
+          if (imp.kind == kExternalFunction) {
+            section.emit_u32v(imp.type);
+          } else if (imp.kind == kExternalGlobal) {
+            section.emit_u32v(imp.type);
+            section.emit_u8(imp.mutable);
+          } else if (imp.kind == kExternalMemory) {
+            var has_max = (typeof imp.maximum) != "undefined";
+            section.emit_u8(has_max ? 1 : 0); // flags
+            section.emit_u32v(imp.initial); // initial
+            if (has_max) section.emit_u32v(imp.maximum); // maximum
+          } else if (imp.kind == kExternalTable) {
+            section.emit_u8(kWasmAnyFunctionTypeForm);
+            var has_max = (typeof imp.maximum) != "undefined";
+            section.emit_u8(has_max ? 1 : 0); // flags
+            section.emit_u32v(imp.initial); // initial
+            if (has_max) section.emit_u32v(imp.maximum); // maximum
+          } else {
+            throw new Error("unknown/unsupported import kind " + imp.kind);
+          }
+        }
+      });
+    }
+
+    // Add functions declarations
+    let has_names = false;
+    let names = false;
+    if (wasm.functions.length > 0) {
+      if (debug) print("emitting function decls @ " + binary.length);
+      binary.emit_section(kFunctionSectionCode, section => {
+        section.emit_u32v(wasm.functions.length);
+        for (let func of wasm.functions) {
+          has_names = has_names || (func.name != undefined &&
+                                   func.name.length > 0);
+          section.emit_u32v(func.type_index);
+        }
+      });
+    }
+
+    // Add function_table.
+    if (wasm.function_table_length > 0) {
+      if (debug) print("emitting table @ " + binary.length);
+      binary.emit_section(kTableSectionCode, section => {
+        section.emit_u8(1);  // one table entry
+        section.emit_u8(kWasmAnyFunctionTypeForm);
+        section.emit_u8(1);
+        section.emit_u32v(wasm.function_table_length);
+        section.emit_u32v(wasm.function_table_length);
+      });
+    }
+
+    // Add memory section
+    if (wasm.memory != undefined) {
+      if (debug) print("emitting memory @ " + binary.length);
+      binary.emit_section(kMemorySectionCode, section => {
+        section.emit_u8(1);  // one memory entry
+        section.emit_u32v(kResizableMaximumFlag);
+        section.emit_u32v(wasm.memory.min);
+        section.emit_u32v(wasm.memory.max);
+      });
+    }
+
+    // Add global section.
+    if (wasm.globals.length > 0) {
+      if (debug) print ("emitting globals @ " + binary.length);
+      binary.emit_section(kGlobalSectionCode, section => {
+        section.emit_u32v(wasm.globals.length);
+        for (let global of wasm.globals) {
+          section.emit_u8(global.type);
+          section.emit_u8(global.mutable);
+          if ((typeof global.init_index) == "undefined") {
+            // Emit a constant initializer.
+            switch (global.type) {
+            case kWasmI32:
+              section.emit_u8(kExprI32Const);
+              section.emit_u32v(global.init);
+              break;
+            case kWasmI64:
+              section.emit_u8(kExprI64Const);
+              section.emit_u32v(global.init);
+              break;
+            case kWasmF32:
+              section.emit_u8(kExprF32Const);
+              f32_view[0] = global.init;
+              section.emit_u8(byte_view[0]);
+              section.emit_u8(byte_view[1]);
+              section.emit_u8(byte_view[2]);
+              section.emit_u8(byte_view[3]);
+              break;
+            case kWasmF64:
+              section.emit_u8(kExprF64Const);
+              f64_view[0] = global.init;
+              section.emit_u8(byte_view[0]);
+              section.emit_u8(byte_view[1]);
+              section.emit_u8(byte_view[2]);
+              section.emit_u8(byte_view[3]);
+              section.emit_u8(byte_view[4]);
+              section.emit_u8(byte_view[5]);
+              section.emit_u8(byte_view[6]);
+              section.emit_u8(byte_view[7]);
+              break;
+            }
+          } else {
+            // Emit a global-index initializer.
+            section.emit_u8(kExprGetGlobal);
+            section.emit_u32v(global.init_index);
+          }
+          section.emit_u8(kExprEnd);  // end of init expression
+        }
+      });
+    }
+
+    // Add export table.
+    var mem_export = (wasm.memory != undefined && wasm.memory.exp);
+    var exports_count = wasm.exports.length + (mem_export ? 1 : 0);
+    if (exports_count > 0) {
+      if (debug) print("emitting exports @ " + binary.length);
+      binary.emit_section(kExportSectionCode, section => {
+        section.emit_u32v(exports_count);
+        for (let exp of wasm.exports) {
+          section.emit_string(exp.name);
+          section.emit_u8(exp.kind);
+          section.emit_u32v(exp.index);
+        }
+        if (mem_export) {
+          section.emit_string("memory");
+          section.emit_u8(kExternalMemory);
+          section.emit_u8(0);
+        }
+      });
+    }
+
+    // Add start function section.
+    if (wasm.start_index != undefined) {
+      if (debug) print("emitting start function @ " + binary.length);
+      binary.emit_section(kStartSectionCode, section => {
+        section.emit_u32v(wasm.start_index);
+      });
+    }
+
+    // Add table elements.
+    if (wasm.function_table_inits.length > 0) {
+      if (debug) print("emitting table @ " + binary.length);
+      binary.emit_section(kElementSectionCode, section => {
+        var inits = wasm.function_table_inits;
+        section.emit_u32v(inits.length);
+        section.emit_u8(0); // table index
+
+        for (let init of inits) {
+          if (init.is_global) {
+            section.emit_u8(kExprGetGlobal);
+          } else {
+            section.emit_u8(kExprI32Const);
+          }
+          section.emit_u32v(init.base);
+          section.emit_u8(kExprEnd);
+          section.emit_u32v(init.array.length);
+          for (let index of init.array) {
+            section.emit_u32v(index);
+          }
+        }
+      });
+    }
+
+    // Add function bodies.
+    if (wasm.functions.length > 0) {
+      // emit function bodies
+      if (debug) print("emitting code @ " + binary.length);
+      binary.emit_section(kCodeSectionCode, section => {
+        section.emit_u32v(wasm.functions.length);
+        for (let func of wasm.functions) {
+          // Function body length will be patched later.
+          let local_decls = [];
+          let l = func.locals;
+          if (l != undefined) {
+            let local_decls_count = 0;
+            if (l.i32_count > 0) {
+              local_decls.push({count: l.i32_count, type: kWasmI32});
+            }
+            if (l.i64_count > 0) {
+              local_decls.push({count: l.i64_count, type: kWasmI64});
+            }
+            if (l.f32_count > 0) {
+              local_decls.push({count: l.f32_count, type: kWasmF32});
+            }
+            if (l.f64_count > 0) {
+              local_decls.push({count: l.f64_count, type: kWasmF64});
+            }
+          }
+
+          let header = new Binary;
+          header.emit_u32v(local_decls.length);
+          for (let decl of local_decls) {
+            header.emit_u32v(decl.count);
+            header.emit_u8(decl.type);
+          }
+
+          section.emit_u32v(header.length + func.body.length);
+          section.emit_bytes(header);
+          section.emit_bytes(func.body);
+        }
+      });
+    }
+
+    // Add data segments.
+    if (wasm.segments.length > 0) {
+      if (debug) print("emitting data segments @ " + binary.length);
+      binary.emit_section(kDataSectionCode, section => {
+        section.emit_u32v(wasm.segments.length);
+        for (let seg of wasm.segments) {
+          section.emit_u8(0);  // linear memory index 0
+          if (seg.is_global) {
+            // initializer is a global variable
+            section.emit_u8(kExprGetGlobal);
+            section.emit_u32v(seg.addr);
+          } else {
+            // initializer is a constant
+            section.emit_u8(kExprI32Const);
+            section.emit_u32v(seg.addr);
+          }
+          section.emit_u8(kExprEnd);
+          section.emit_u32v(seg.data.length);
+          section.emit_bytes(seg.data);
+        }
+      });
+    }
+
+    // Add any explicitly added sections
+    for (let exp of wasm.explicit) {
+      if (debug) print("emitting explicit @ " + binary.length);
+      binary.emit_bytes(exp);
+    }
+
+    // Add function names.
+    if (has_names) {
+      if (debug) print("emitting names @ " + binary.length);
+      binary.emit_section(kUnknownSectionCode, section => {
+        section.emit_string("name");
+        var count = wasm.functions.length + wasm.num_imported_funcs;
+        section.emit_u32v(count);
+        for (var i = 0; i < wasm.num_imported_funcs; i++) {
+          section.emit_u8(0); // empty string
+          section.emit_u8(0); // local names count == 0
+        }
+        for (let func of wasm.functions) {
+          var name = func.name == undefined ? "" : func.name;
+          section.emit_string(name);
+          section.emit_u8(0);  // local names count == 0
+        }
+      });
+    }
+
+    return binary;
+  }
+
+  toBuffer(debug = false) {
+    let bytes = this.toArray(debug);
+    let buffer = new ArrayBuffer(bytes.length);
+    let view = new Uint8Array(buffer);
+    for (let i = 0; i < bytes.length; i++) {
+      let val = bytes[i];
+      if ((typeof val) == "string") val = val.charCodeAt(0);
+      view[i] = val | 0;
+    }
+    return buffer;
+  }
+
+  instantiate(ffi) {
+    let module = new WebAssembly.Module(this.toBuffer());
+    let instance = new WebAssembly.Instance(module, ffi);
+    return instance;
+  }
+}