Reland "[snapshot] Emit the embedded blob as assembly instead of inline assembly"

This is a reland of 0b13f0f5

Original change's description:
> [snapshot] Emit the embedded blob as assembly instead of inline assembly
>
> The motivation behind this is that MSVC doesn't support inline assembly
> on x64. Emitting the embedded blob as a plain assembly file will give us
> MSVC support (and possibly faster compilation times as a side-effect).
>
> Bug: v8:6666,v8:8349
> Change-Id: I2e6cf072faa9ef406fe721a05b63912c655546c2
> Reviewed-on: https://chromium-review.googlesource.com/c/1329205
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Michael Stanton <mvstanton@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#57524}

Tbr: yangguo@chromium.org,mvstanton@chromium.org
Bug: v8:6666, v8:8349
Change-Id: Ib35696b60a9cd01bc2edf459c8e8d84716e3438d
Reviewed-on: https://chromium-review.googlesource.com/c/1337733Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57546}

BUILD.gn

@@ -24,8 +24,6 @@ import("snapshot_toolchain.gni")
 is_target_simulator = (target_cpu != v8_target_cpu && !v8_multi_arch_build) ||
                       (current_cpu != v8_current_cpu && v8_multi_arch_build)
 
-is_msvc = is_win && !is_clang
-
 declare_args() {
   # Print to stdout on Android.
   v8_android_log_stdout = false
@@ -85,8 +83,8 @@ declare_args() {
   v8_enable_fast_mksnapshot = false
 
   # Enable embedded builtins.
-  # TODO(v8:6666): Support aix and MSVC.
-  v8_enable_embedded_builtins = !is_aix && !is_msvc
+  # TODO(v8:8043): Support aix.
+  v8_enable_embedded_builtins = !is_aix
 
   # Build-time flag for enabling nojit mode.
   # TODO(v8:7777): Remove the build-time flag once the --jitless runtime flag
@@ -1035,7 +1033,7 @@ action("generate_bytecode_builtins_list") {
 # Template to generate different V8 snapshots based on different runtime flags.
 # Can be invoked with run_mksnapshot(<name>). The target will resolve to
 # run_mksnapshot_<name>. If <name> is "default", no file suffixes will be used.
-# Otherwise files are suffixed, e.g. embedded_<name>.cc and
+# Otherwise files are suffixed, e.g. embedded_<name>.S and
 # snapshot_blob_<name>.bin.
 #
 # The template exposes the variables:
@@ -1074,10 +1072,10 @@ template("run_mksnapshot") {
     args += invoker.args
 
     if (v8_enable_embedded_builtins) {
-      outputs += [ "$target_gen_dir/embedded${suffix}.cc" ]
+      outputs += [ "$target_gen_dir/embedded${suffix}.S" ]
       args += [
         "--embedded_src",
-        rebase_path("$target_gen_dir/embedded${suffix}.cc", root_build_dir),
+        rebase_path("$target_gen_dir/embedded${suffix}.S", root_build_dir),
       ]
       if (invoker.embedded_variant != "") {
         args += [
@@ -1281,7 +1279,7 @@ if (v8_use_snapshot && !v8_use_external_startup_data) {
     ]
 
     if (v8_enable_embedded_builtins) {
-      sources += [ "$target_gen_dir/embedded.cc" ]
+      sources += [ "$target_gen_dir/embedded.S" ]
     } else {
       sources += [ "src/snapshot/embedded-empty.cc" ]
     }
@@ -1328,15 +1326,15 @@ if (v8_use_snapshot && v8_use_external_startup_data) {
     public = []
 
     if (v8_enable_embedded_builtins) {
-      sources += [ "$target_gen_dir/embedded.cc" ]
+      sources += [ "$target_gen_dir/embedded.S" ]
 
       if (v8_use_multi_snapshots) {
-        sources += [ "$target_gen_dir/embedded_trusted.cc" ]
+        sources += [ "$target_gen_dir/embedded_trusted.S" ]
 
         if (use_jumbo_build == true) {
           jumbo_excluded_sources = [
-            # Duplicated symbols with embedded.cc
-            "$target_gen_dir/embedded_trusted.cc",
+            # Duplicated symbols with embedded.S
+            "$target_gen_dir/embedded_trusted.S",
           ]
         }
       }
@@ -2493,7 +2491,6 @@ v8_source_set("v8_base") {
     "src/snapshot/deserializer-allocator.h",
     "src/snapshot/deserializer.cc",
     "src/snapshot/deserializer.h",
-    "src/snapshot/macros.h",
     "src/snapshot/natives-common.cc",
     "src/snapshot/natives.h",
     "src/snapshot/object-deserializer.cc",
@@ -3419,6 +3416,8 @@ if (v8_use_snapshot && current_toolchain == v8_snapshot_toolchain) {
     visibility = [ ":*" ]  # Only targets in this file can depend on this.
 
     sources = [
+      "src/snapshot/embedded-file-writer.cc",
+      "src/snapshot/embedded-file-writer.h",
       "src/snapshot/mksnapshot.cc",
     ]
 

src/isolate.cc

@@ -73,6 +73,9 @@
 #include "unicode/uobject.h"
 #endif  // V8_INTL_SUPPORT
 
+extern "C" const uint8_t* v8_Default_embedded_blob_;
+extern "C" uint32_t v8_Default_embedded_blob_size_;
+
 namespace v8 {
 namespace internal {
 
@@ -88,12 +91,15 @@ namespace internal {
 #define TRACE_ISOLATE(tag)
 #endif
 
-extern const uint8_t* DefaultEmbeddedBlob();
-extern uint32_t DefaultEmbeddedBlobSize();
+const uint8_t* DefaultEmbeddedBlob() { return v8_Default_embedded_blob_; }
+uint32_t DefaultEmbeddedBlobSize() { return v8_Default_embedded_blob_size_; }
 
 #ifdef V8_MULTI_SNAPSHOTS
-extern const uint8_t* TrustedEmbeddedBlob();
-extern uint32_t TrustedEmbeddedBlobSize();
+extern "C" const uint8_t* v8_Trusted_embedded_blob_;
+extern "C" uint32_t v8_Trusted_embedded_blob_size_;
+
+const uint8_t* TrustedEmbeddedBlob() { return v8_Trusted_embedded_blob_; }
+uint32_t TrustedEmbeddedBlobSize() { return v8_Trusted_embedded_blob_size_; }
 #endif
 
 namespace {

src/objects-debug.cc

@@ -1160,7 +1160,7 @@ void CodeDataContainer::CodeDataContainerVerify(Isolate* isolate) {
 
 void Code::CodeVerify(Isolate* isolate) {
   CHECK_LE(constant_pool_offset(), InstructionSize());
-  CHECK(IsAligned(InstructionStart(), kCodeAlignment));
+  CHECK(IsAligned(raw_instruction_start(), kCodeAlignment));
   relocation_info()->ObjectVerify(isolate);
   Address last_gc_pc = kNullAddress;
 

src/snapshot/embedded-empty.cc

@@ -6,16 +6,18 @@
 
 #include <cstdint>
 
-namespace v8 {
-namespace internal {
+#include "src/base/macros.h"
 
-const uint8_t* DefaultEmbeddedBlob() { return nullptr; }
-uint32_t DefaultEmbeddedBlobSize() { return 0; }
+extern "C" const uint8_t* v8_Default_embedded_blob_;
+extern "C" uint32_t v8_Default_embedded_blob_size_;
+
+const uint8_t* v8_Default_embedded_blob_ = nullptr;
+uint32_t v8_Default_embedded_blob_size_ = 0;
 
 #ifdef V8_MULTI_SNAPSHOTS
-const uint8_t* TrustedEmbeddedBlob() { return nullptr; }
-uint32_t TrustedEmbeddedBlobSize() { return 0; }
-#endif
+extern "C" const uint8_t* v8_Trusted_embedded_blob_;
+extern "C" uint32_t v8_Trusted_embedded_blob_size_;
 
-}  // namespace internal
-}  // namespace v8
+const uint8_t* v8_Trusted_embedded_blob_ = nullptr;
+uint32_t v8_Trusted_embedded_blob_size_ = 0;
+#endif

src/snapshot/embedded-file-writer.cc

+// Copyright 2018 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/snapshot/embedded-file-writer.h"
+
+namespace v8 {
+namespace internal {
+
+// Platform-independent bits.
+// -----------------------------------------------------------------------------
+
+namespace {
+
+DataDirective PointerSizeDirective() {
+  if (kPointerSize == 8) {
+    return kQuad;
+  } else {
+    CHECK_EQ(4, kPointerSize);
+    return kLong;
+  }
+}
+
+}  // namespace
+
+// static
+const char* PlatformDependentEmbeddedFileWriter::DirectiveAsString(
+    DataDirective directive) {
+#ifndef V8_OS_WIN
+  switch (directive) {
+    case kByte:
+      return ".byte";
+    case kLong:
+      return ".long";
+    case kQuad:
+      return ".quad";
+    case kOcta:
+      return ".octa";
+  }
+  UNREACHABLE();
+#else
+  switch (directive) {
+    case kByte:
+      return "BYTE";
+    case kLong:
+      return "DWORD";
+    case kQuad:
+      return "QWORD";
+    default:
+      UNREACHABLE();
+  }
+#endif
+}
+
+// V8_OS_MACOSX
+// -----------------------------------------------------------------------------
+
+#if defined(V8_OS_MACOSX)
+
+void PlatformDependentEmbeddedFileWriter::SectionText() {
+  fprintf(fp_, ".text\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionData() {
+  fprintf(fp_, ".data\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionRoData() {
+  fprintf(fp_, ".const_data\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareUint32(const char* name,
+                                                        uint32_t value) {
+  DeclareSymbolGlobal(name);
+  DeclareLabel(name);
+  IndentedDataDirective(kLong);
+  fprintf(fp_, "%d", value);
+  Newline();
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclarePointerToSymbol(
+    const char* name, const char* target) {
+  DeclareSymbolGlobal(name);
+  DeclareLabel(name);
+  fprintf(fp_, "  %s _%s\n", DirectiveAsString(PointerSizeDirective()), target);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareSymbolGlobal(
+    const char* name) {
+  // TODO(jgruber): Investigate switching to .globl. Using .private_extern
+  // prevents something along the compilation chain from messing with the
+  // embedded blob. Using .global here causes embedded blob hash verification
+  // failures at runtime.
+  fprintf(fp_, ".private_extern _%s\n", name);
+}
+
+void PlatformDependentEmbeddedFileWriter::AlignToCodeAlignment() {
+  fprintf(fp_, ".balign 32\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::Comment(const char* string) {
+  fprintf(fp_, "// %s\n", string);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareLabel(const char* name) {
+  fprintf(fp_, "_%s:\n", name);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionBegin(
+    const char* name) {
+  DeclareLabel(name);
+
+  // TODO(mvstanton): Investigate the proper incantations to mark the label as
+  // a function on OSX.
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionEnd(const char* name) {
+}
+
+int PlatformDependentEmbeddedFileWriter::HexLiteral(int value) {
+  return fprintf(fp_, "0x%x", value);
+}
+
+void PlatformDependentEmbeddedFileWriter::FilePrologue() {}
+
+void PlatformDependentEmbeddedFileWriter::FileEpilogue() {}
+
+int PlatformDependentEmbeddedFileWriter::IndentedDataDirective(
+    DataDirective directive) {
+  return fprintf(fp_, "  %s ", DirectiveAsString(directive));
+}
+
+// V8_OS_AIX
+// -----------------------------------------------------------------------------
+
+#elif defined(V8_OS_AIX)
+
+// TODO(aix): Update custom logic previously contained in section header macros.
+// See
+// https://cs.chromium.org/chromium/src/v8/src/snapshot/macros.h?l=81&rcl=31b2546b348e864539ade15897eac971b3c0e402
+
+void PlatformDependentEmbeddedFileWriter::SectionText() {
+  fprintf(fp_, ".csect .text[PR]\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionData() {
+  // TODO(aix): Confirm and update if needed.
+  fprintf(fp_, ".csect .data[RW]\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionRoData() {
+  fprintf(fp_, ".csect[RO]\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareUint32(const char* name,
+                                                        uint32_t value) {
+  DeclareSymbolGlobal(name);
+  DeclareLabel(name);
+  IndentedDataDirective(kLong);
+  fprintf(fp_, "%d", value);
+  Newline();
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclarePointerToSymbol(
+    const char* name, const char* target) {
+  DeclareSymbolGlobal(name);
+  DeclareLabel(name);
+  fprintf(fp_, "  %s %s\n", DirectiveAsString(PointerSizeDirective()), target);
+  Newline();
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareSymbolGlobal(
+    const char* name) {
+  fprintf(fp_, ".globl %s\n", name);
+}
+
+void PlatformDependentEmbeddedFileWriter::AlignToCodeAlignment() {
+  fprintf(fp_, ".balign 32\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::Comment(const char* string) {
+  fprintf(fp_, "// %s\n", string);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareLabel(const char* name) {
+  fprintf(fp_, "%s:\n", name);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionBegin(
+    const char* name) {
+  DeclareLabel(name);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionEnd(const char* name) {
+}
+
+int PlatformDependentEmbeddedFileWriter::HexLiteral(int value) {
+  return fprintf(fp_, "0x%x", value);
+}
+
+void PlatformDependentEmbeddedFileWriter::FilePrologue() {}
+
+void PlatformDependentEmbeddedFileWriter::FileEpilogue() {}
+
+int PlatformDependentEmbeddedFileWriter::IndentedDataDirective(
+    DataDirective directive) {
+  return fprintf(fp_, "  %s ", DirectiveAsString(directive));
+}
+
+// V8_OS_WIN
+// -----------------------------------------------------------------------------
+
+#elif defined(V8_OS_WIN)
+
+// See https://docs.microsoft.com/en-us/cpp/assembler/masm/directives-reference.
+
+void PlatformDependentEmbeddedFileWriter::SectionText() {
+  fprintf(fp_, ".CODE\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionData() {
+  fprintf(fp_, ".DATA\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionRoData() {
+  fprintf(fp_, ".CONST\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareUint32(const char* name,
+                                                        uint32_t value) {
+  DeclareSymbolGlobal(name);
+#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, "%s %s %d\n", name, DirectiveAsString(kLong), value);
+#else
+  fprintf(fp_, "_%s %s %d\n", name, DirectiveAsString(kLong), value);
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclarePointerToSymbol(
+    const char* name, const char* target) {
+  DeclareSymbolGlobal(name);
+#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, "%s %s %s\n", name, DirectiveAsString(PointerSizeDirective()),
+          target);
+#else
+  fprintf(fp_, "_%s %s _%s\n", name, DirectiveAsString(PointerSizeDirective()),
+          target);
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareSymbolGlobal(
+    const char* name) {
+#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, "PUBLIC %s\n", name);
+#else
+  fprintf(fp_, "PUBLIC _%s\n", name);
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::AlignToCodeAlignment() {
+  // Diverges from other platforms due to compile error
+  // 'invalid combination with segment alignment'.
+  fprintf(fp_, "ALIGN 4\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::Comment(const char* string) {
+  fprintf(fp_, "; %s\n", string);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareLabel(const char* name) {
+#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, "%s LABEL %s\n", name, DirectiveAsString(kByte));
+#else
+  fprintf(fp_, "_%s LABEL %s\n", name, DirectiveAsString(kByte));
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionBegin(
+    const char* name) {
+#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, "%s PROC\n", name);
+#else
+  fprintf(fp_, "_%s PROC\n", name);
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionEnd(const char* name) {
+#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, "%s ENDP\n", name);
+#else
+  fprintf(fp_, "_%s ENDP\n", name);
+#endif
+}
+
+int PlatformDependentEmbeddedFileWriter::HexLiteral(int value) {
+  return fprintf(fp_, "0%xh", value);
+}
+
+void PlatformDependentEmbeddedFileWriter::FilePrologue() {
+#if !defined(V8_TARGET_ARCH_X64) && !defined(V8_TARGET_ARCH_ARM64)
+  fprintf(fp_, ".MODEL FLAT\n");
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::FileEpilogue() {
+  fprintf(fp_, "END\n");
+}
+
+int PlatformDependentEmbeddedFileWriter::IndentedDataDirective(
+    DataDirective directive) {
+  return fprintf(fp_, "  %s ", DirectiveAsString(directive));
+}
+
+// Everything but AIX, Windows, or OSX.
+// -----------------------------------------------------------------------------
+
+#else
+
+void PlatformDependentEmbeddedFileWriter::SectionText() {
+#ifdef OS_CHROMEOS
+  fprintf(fp_, ".section .text.hot.embedded\n");
+#else
+  fprintf(fp_, ".section .text\n");
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionData() {
+  fprintf(fp_, ".section .data\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::SectionRoData() {
+  fprintf(fp_, ".section .rodata\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareUint32(const char* name,
+                                                        uint32_t value) {
+  DeclareSymbolGlobal(name);
+  DeclareLabel(name);
+  IndentedDataDirective(kLong);
+  fprintf(fp_, "%d", value);
+  Newline();
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclarePointerToSymbol(
+    const char* name, const char* target) {
+  DeclareSymbolGlobal(name);
+  DeclareLabel(name);
+  fprintf(fp_, "  %s %s\n", DirectiveAsString(PointerSizeDirective()), target);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareSymbolGlobal(
+    const char* name) {
+  fprintf(fp_, ".global %s\n", name);
+}
+
+void PlatformDependentEmbeddedFileWriter::AlignToCodeAlignment() {
+  fprintf(fp_, ".balign 32\n");
+}
+
+void PlatformDependentEmbeddedFileWriter::Comment(const char* string) {
+  fprintf(fp_, "// %s\n", string);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareLabel(const char* name) {
+  fprintf(fp_, "%s:\n", name);
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionBegin(
+    const char* name) {
+  DeclareLabel(name);
+
+#if defined(V8_TARGET_ARCH_ARM) || defined(V8_TARGET_ARCH_ARM64)
+  // ELF format binaries on ARM use ".type <function name>, %function"
+  // to create a DWARF subprogram entry.
+  fprintf(fp_, ".type %s, %%function\n", name);
+#else
+  // Other ELF Format binaries use ".type <function name>, @function"
+  // to create a DWARF subprogram entry.
+  fprintf(fp_, ".type %s, @function\n", name);
+#endif
+}
+
+void PlatformDependentEmbeddedFileWriter::DeclareFunctionEnd(const char* name) {
+}
+
+int PlatformDependentEmbeddedFileWriter::HexLiteral(int value) {
+  return fprintf(fp_, "0x%x", value);
+}
+
+void PlatformDependentEmbeddedFileWriter::FilePrologue() {}
+
+void PlatformDependentEmbeddedFileWriter::FileEpilogue() {}
+
+int PlatformDependentEmbeddedFileWriter::IndentedDataDirective(
+    DataDirective directive) {
+  return fprintf(fp_, "  %s ", DirectiveAsString(directive));
+}
+
+#endif
+
+}  // namespace internal
+}  // namespace v8

src/snapshot/embedded-file-writer.h

+// Copyright 2018 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.
+
+#ifndef V8_SNAPSHOT_EMBEDDED_FILE_WRITER_H_
+#define V8_SNAPSHOT_EMBEDDED_FILE_WRITER_H_
+
+#include <cstdio>
+#include <cstring>
+
+#include "src/globals.h"
+#include "src/snapshot/snapshot.h"
+
+namespace v8 {
+namespace internal {
+
+enum DataDirective {
+  kByte,
+  kLong,
+  kQuad,
+  kOcta,
+};
+
+static constexpr char kDefaultEmbeddedVariant[] = "Default";
+
+// The platform-dependent logic for emitting assembly code for the generated
+// embedded.S file.
+class PlatformDependentEmbeddedFileWriter final {
+ public:
+  void SetFile(FILE* fp) { fp_ = fp; }
+
+  void SectionText();
+  void SectionData();
+  void SectionRoData();
+
+  void AlignToCodeAlignment();
+
+  void DeclareUint32(const char* name, uint32_t value);
+  void DeclarePointerToSymbol(const char* name, const char* target);
+
+  void DeclareLabel(const char* name);
+
+  void DeclareFunctionBegin(const char* name);
+  void DeclareFunctionEnd(const char* name);
+
+  // Returns the number of printed characters.
+  int HexLiteral(int value);
+
+  void Comment(const char* string);
+  void Newline() { fprintf(fp_, "\n"); }
+
+  void FilePrologue();
+  void FileEpilogue();
+
+  int IndentedDataDirective(DataDirective directive);
+
+  FILE* fp() const { return fp_; }
+
+ private:
+  void DeclareSymbolGlobal(const char* name);
+
+  static const char* DirectiveAsString(DataDirective directive);
+
+ private:
+  FILE* fp_ = nullptr;
+};
+
+// Generates the embedded.S file which is later compiled into the final v8
+// binary. Its contents are exported through two symbols:
+//
+// v8_<variant>_embedded_blob_ (intptr_t):
+//     a pointer to the start of the embedded blob.
+// v8_<variant>_embedded_blob_size_ (uint32_t):
+//     size of the embedded blob in bytes.
+//
+// The variant is usually "Default" but can be modified in multisnapshot builds.
+class EmbeddedFileWriter {
+ public:
+  void SetEmbeddedFile(const char* embedded_cpp_file) {
+    embedded_cpp_path_ = embedded_cpp_file;
+  }
+
+  void SetEmbeddedVariant(const char* embedded_variant) {
+    embedded_variant_ = embedded_variant;
+  }
+
+  void WriteEmbedded(const i::EmbeddedData* blob) const {
+    MaybeWriteEmbeddedFile(blob);
+  }
+
+ private:
+  void MaybeWriteEmbeddedFile(const i::EmbeddedData* blob) const {
+    if (embedded_cpp_path_ == nullptr) return;
+
+    FILE* fp = GetFileDescriptorOrDie(embedded_cpp_path_);
+
+    PlatformDependentEmbeddedFileWriter writer;
+    writer.SetFile(fp);
+
+    WriteFilePrologue(&writer);
+    WriteMetadataSection(&writer, blob);
+    WriteInstructionStreams(&writer, blob);
+    WriteFileEpilogue(&writer, blob);
+
+    fclose(fp);
+  }
+
+  static FILE* GetFileDescriptorOrDie(const char* filename) {
+    FILE* fp = v8::base::OS::FOpen(filename, "wb");
+    if (fp == nullptr) {
+      i::PrintF("Unable to open file \"%s\" for writing.\n", filename);
+      exit(1);
+    }
+    return fp;
+  }
+
+  static void WriteFilePrologue(PlatformDependentEmbeddedFileWriter* w) {
+    w->Comment("Autogenerated file. Do not edit.");
+    w->Newline();
+    w->FilePrologue();
+  }
+
+  // Fairly arbitrary but should fit all symbol names.
+  static constexpr int kTemporaryStringLength = 256;
+
+  void WriteMetadataSection(PlatformDependentEmbeddedFileWriter* w,
+                            const i::EmbeddedData* blob) const {
+    char embedded_blob_data_symbol[kTemporaryStringLength];
+    i::SNPrintF(i::Vector<char>(embedded_blob_data_symbol),
+                "v8_%s_embedded_blob_data_", embedded_variant_);
+
+    w->Comment("The embedded blob starts here. Metadata comes first, followed");
+    w->Comment("by builtin instruction streams.");
+    w->SectionText();
+    w->AlignToCodeAlignment();
+    w->DeclareLabel(embedded_blob_data_symbol);
+
+    WriteBinaryContentsAsInlineAssembly(w, blob->data(),
+                                        i::EmbeddedData::RawDataOffset());
+  }
+
+  void WriteInstructionStreams(PlatformDependentEmbeddedFileWriter* w,
+                               const i::EmbeddedData* blob) const {
+    const bool is_default_variant =
+        std::strcmp(embedded_variant_, kDefaultEmbeddedVariant) == 0;
+
+    for (int i = 0; i < i::Builtins::builtin_count; i++) {
+      if (!blob->ContainsBuiltin(i)) continue;
+
+      char builtin_symbol[kTemporaryStringLength];
+      if (is_default_variant) {
+        // Create nicer symbol names for the default mode.
+        i::SNPrintF(i::Vector<char>(builtin_symbol), "Builtins_%s",
+                    i::Builtins::name(i));
+      } else {
+        i::SNPrintF(i::Vector<char>(builtin_symbol), "%s_Builtins_%s",
+                    embedded_variant_, i::Builtins::name(i));
+      }
+
+      // Labels created here will show up in backtraces. We check in
+      // Isolate::SetEmbeddedBlob that the blob layout remains unchanged, i.e.
+      // that labels do not insert bytes into the middle of the blob byte
+      // stream.
+      w->DeclareFunctionBegin(builtin_symbol);
+      WriteBinaryContentsAsInlineAssembly(
+          w,
+          reinterpret_cast<const uint8_t*>(blob->InstructionStartOfBuiltin(i)),
+          blob->PaddedInstructionSizeOfBuiltin(i));
+      w->DeclareFunctionEnd(builtin_symbol);
+    }
+    w->Newline();
+  }
+
+  void WriteFileEpilogue(PlatformDependentEmbeddedFileWriter* w,
+                         const i::EmbeddedData* blob) const {
+    {
+      char embedded_blob_data_symbol[kTemporaryStringLength];
+      i::SNPrintF(i::Vector<char>(embedded_blob_data_symbol),
+                  "v8_%s_embedded_blob_data_", embedded_variant_);
+
+      char embedded_blob_symbol[kTemporaryStringLength];
+      i::SNPrintF(i::Vector<char>(embedded_blob_symbol), "v8_%s_embedded_blob_",
+                  embedded_variant_);
+
+      w->Comment("Pointer to the beginning of the embedded blob.");
+      w->SectionData();
+      w->DeclarePointerToSymbol(embedded_blob_symbol,
+                                embedded_blob_data_symbol);
+      w->Newline();
+    }
+
+    {
+      char embedded_blob_size_symbol[kTemporaryStringLength];
+      i::SNPrintF(i::Vector<char>(embedded_blob_size_symbol),
+                  "v8_%s_embedded_blob_size_", embedded_variant_);
+
+      w->Comment("The size of the embedded blob in bytes.");
+      w->SectionRoData();
+      w->DeclareUint32(embedded_blob_size_symbol, blob->size());
+      w->Newline();
+    }
+
+    w->FileEpilogue();
+  }
+
+  static int WriteOcta(FILE* fp, int current_line_length, const uint8_t* data) {
+    const uint64_t* quad_ptr1 = reinterpret_cast<const uint64_t*>(data);
+    const uint64_t* quad_ptr2 = reinterpret_cast<const uint64_t*>(data + 8);
+
+#ifdef V8_TARGET_BIG_ENDIAN
+    uint64_t part1 = *quad_ptr1;
+    uint64_t part2 = *quad_ptr2;
+#else
+    uint64_t part1 = *quad_ptr2;
+    uint64_t part2 = *quad_ptr1;
+#endif  // V8_TARGET_BIG_ENDIAN
+
+    if (part1 != 0) {
+      current_line_length +=
+          fprintf(fp, "0x%" PRIx64 "%016" PRIx64, part1, part2);
+    } else {
+      current_line_length += fprintf(fp, "0x%" PRIx64, part2);
+    }
+    return current_line_length;
+  }
+
+  static int WriteDirectiveOrSeparator(PlatformDependentEmbeddedFileWriter* w,
+                                       int current_line_length,
+                                       DataDirective directive) {
+    int printed_chars;
+    if (current_line_length == 0) {
+      printed_chars = w->IndentedDataDirective(directive);
+      DCHECK_LT(0, printed_chars);
+    } else {
+      printed_chars = fprintf(w->fp(), ",");
+      DCHECK_EQ(1, printed_chars);
+    }
+    return current_line_length + printed_chars;
+  }
+
+  static int WriteLineEndIfNeeded(FILE* fp, int current_line_length,
+                                  int write_size) {
+    static const int kTextWidth = 80;
+    // Check if adding ',0xFF...FF\n"' would force a line wrap. This doesn't use
+    // the actual size of the string to be written to determine this so it's
+    // more conservative than strictly needed.
+    if (current_line_length + strlen(",0x") + write_size * 2 > kTextWidth) {
+      fprintf(fp, "\n");
+      return 0;
+    } else {
+      return current_line_length;
+    }
+  }
+
+  static void WriteBinaryContentsAsInlineAssembly(
+      PlatformDependentEmbeddedFileWriter* w, const uint8_t* data,
+      uint32_t size) {
+    int current_line_length = 0;
+
+    uint32_t i = 0;
+#ifndef V8_OS_WIN
+    const uint32_t size_of_octa = 16;
+    for (; i <= size - size_of_octa; i += size_of_octa) {
+      current_line_length =
+          WriteDirectiveOrSeparator(w, current_line_length, kOcta);
+      current_line_length = WriteOcta(w->fp(), current_line_length, data + i);
+      current_line_length =
+          WriteLineEndIfNeeded(w->fp(), current_line_length, size_of_octa);
+    }
+    if (current_line_length != 0) w->Newline();
+    current_line_length = 0;
+#endif
+    for (; i < size; i++) {
+      current_line_length =
+          WriteDirectiveOrSeparator(w, current_line_length, kByte);
+      current_line_length += w->HexLiteral(data[i]);
+      current_line_length =
+          WriteLineEndIfNeeded(w->fp(), current_line_length, 1);
+    }
+    if (current_line_length != 0) w->Newline();
+  }
+
+  const char* embedded_cpp_path_ = nullptr;
+  const char* embedded_variant_ = kDefaultEmbeddedVariant;
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_SNAPSHOT_EMBEDDED_FILE_WRITER_H_

src/snapshot/macros.h

-// Copyright 2018 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.
-
-#ifndef V8_SNAPSHOT_MACROS_H_
-#define V8_SNAPSHOT_MACROS_H_
-
-#include "include/v8config.h"
-
-// .byte portability macros.
-
-#if defined(V8_OS_MACOSX)  // MACOSX
-#define V8_ASM_MANGLE_LABEL "_"
-#define V8_ASM_RODATA_SECTION ".const_data\n"
-#define V8_ASM_TEXT_SECTION ".text\n"
-#define V8_ASM_DECLARE(NAME) ".private_extern " V8_ASM_MANGLE_LABEL NAME "\n"
-#elif defined(V8_OS_AIX)  // AIX
-#define V8_ASM_RODATA_SECTION ".csect[RO]\n"
-#define V8_ASM_TEXT_SECTION ".csect .text[PR]\n"
-#define V8_ASM_MANGLE_LABEL ""
-#define V8_ASM_DECLARE(NAME) ".globl " V8_ASM_MANGLE_LABEL NAME "\n"
-#elif defined(V8_OS_WIN)  // WIN
-#if defined(V8_TARGET_ARCH_X64) || defined(V8_TARGET_ARCH_ARM64)
-#define V8_ASM_MANGLE_LABEL ""
-#else
-#define V8_ASM_MANGLE_LABEL "_"
-#endif
-#define V8_ASM_RODATA_SECTION ".section .rodata\n"
-#define V8_ASM_TEXT_SECTION ".section .text\n"
-#define V8_ASM_DECLARE(NAME)
-#else  // !MACOSX && !WIN && !AIX
-#define V8_ASM_MANGLE_LABEL ""
-#define V8_ASM_RODATA_SECTION ".section .rodata\n"
-#if defined(OS_CHROMEOS)  // ChromeOS
-#define V8_ASM_TEXT_SECTION ".section .text.hot.embedded\n"
-#else
-#define V8_ASM_TEXT_SECTION ".section .text\n"
-#endif
-#if defined(V8_TARGET_ARCH_MIPS) || defined(V8_TARGET_ARCH_MIPS64)
-#define V8_ASM_DECLARE(NAME) ".global " V8_ASM_MANGLE_LABEL NAME "\n"
-#else
-#define V8_ASM_DECLARE(NAME) ".local " V8_ASM_MANGLE_LABEL NAME "\n"
-#endif
-#endif
-
-// Align to kCodeAlignment.
-#define V8_ASM_BALIGN32 ".balign 32\n"
-#define V8_ASM_LABEL(NAME) V8_ASM_MANGLE_LABEL NAME ":\n"
-
-#if defined(V8_OS_WIN)
-// The directives for inserting debugging information on Windows come
-// from the PE (Portable Executable) and COFF (Common Object File Format)
-// standards. Documented here:
-// https://docs.microsoft.com/en-us/windows/desktop/debug/pe-format
-
-#define V8_ASM_TYPE(NAME)                            \
-  /* .scl 2 means StorageClass external. */          \
-  /* .type 32 means Type Representation Function. */ \
-  ".def " V8_ASM_MANGLE_LABEL NAME "; .scl 2; .type 32; .endef;\n"
-
-#elif defined(V8_TARGET_ARCH_ARM) || defined(V8_TARGET_ARCH_ARM64)
-
-// ELF format binaries on ARM use ".type <function name>, %function"
-// to create a DWARF subprogram entry.
-#define V8_ASM_TYPE(NAME) ".type " V8_ASM_MANGLE_LABEL NAME ", %function\n"
-
-#else
-
-// Other ELF Format binaries use ".type <function name>, @function"
-// to create a DWARF subprogram entry.
-#define V8_ASM_TYPE(NAME) ".type " V8_ASM_MANGLE_LABEL NAME ", @function\n"
-#endif  // !V8_OS_WIN
-
-#define V8_ASM_DECLARE_FUNCTION(NAME) \
-  V8_ASM_LABEL(NAME)                  \
-  V8_ASM_TYPE(NAME)
-
-// clang-format off
-#if defined(V8_OS_AIX)
-
-#define V8_EMBEDDED_TEXT_HEADER(LABEL)         \
-  __asm__(V8_ASM_DECLARE(#LABEL)               \
-          ".csect " #LABEL "[DS]\n"            \
-          #LABEL ":\n"                         \
-          ".llong ." #LABEL ", TOC[tc0], 0\n"  \
-          V8_ASM_TEXT_SECTION                  \
-          "." #LABEL ":\n");
-
-#define V8_EMBEDDED_RODATA_HEADER(LABEL)    \
-  __asm__(V8_ASM_RODATA_SECTION             \
-          V8_ASM_DECLARE(#LABEL)            \
-          ".align 5\n"                      \
-          V8_ASM_LABEL(#LABEL));
-
-#else
-
-#define V8_EMBEDDED_TEXT_HEADER(LABEL) \
-  __asm__(V8_ASM_TEXT_SECTION          \
-          V8_ASM_DECLARE(#LABEL)       \
-          V8_ASM_BALIGN32              \
-          V8_ASM_LABEL(#LABEL));
-
-#define V8_EMBEDDED_RODATA_HEADER(LABEL) \
-  __asm__(V8_ASM_RODATA_SECTION          \
-          V8_ASM_DECLARE(#LABEL)         \
-          V8_ASM_BALIGN32                \
-          V8_ASM_LABEL(#LABEL));
-
-#endif  // #if defined(V8_OS_AIX)
-#endif  // V8_SNAPSHOT_MACROS_H_

src/snapshot/mksnapshot.cc

@@ -11,25 +11,16 @@
 #include "src/base/platform/platform.h"
 #include "src/flags.h"
 #include "src/msan.h"
+#include "src/snapshot/embedded-file-writer.h"
 #include "src/snapshot/natives.h"
 #include "src/snapshot/partial-serializer.h"
 #include "src/snapshot/snapshot.h"
 #include "src/snapshot/startup-serializer.h"
 
 namespace {
-class SnapshotWriter {
- public:
-  SnapshotWriter()
-      : snapshot_cpp_path_(nullptr), snapshot_blob_path_(nullptr) {}
-
-  void SetEmbeddedFile(const char* embedded_cpp_file) {
-    embedded_cpp_path_ = embedded_cpp_file;
-  }
-
-  void SetEmbeddedVariant(const char* embedded_variant) {
-    embedded_variant_ = embedded_variant;
-  }
 
+class SnapshotFileWriter {
+ public:
   void SetSnapshotFile(const char* snapshot_cpp_file) {
     snapshot_cpp_path_ = snapshot_cpp_file;
   }
@@ -49,10 +40,6 @@ class SnapshotWriter {
     MaybeWriteStartupBlob(blob_vector);
   }
 
-  void WriteEmbedded(const i::EmbeddedData* blob) const {
-    MaybeWriteEmbeddedFile(blob);
-  }
-
  private:
   void MaybeWriteStartupBlob(const i::Vector<const i::byte>& blob) const {
     if (!snapshot_blob_path_) return;
@@ -116,170 +103,6 @@ class SnapshotWriter {
     fprintf(fp, "\n");
   }
 
-  void MaybeWriteEmbeddedFile(const i::EmbeddedData* blob) const {
-    if (embedded_cpp_path_ == nullptr) return;
-
-    FILE* fp = GetFileDescriptorOrDie(embedded_cpp_path_);
-
-    WriteEmbeddedFilePrefix(fp);
-    WriteEmbeddedFileData(fp, blob, embedded_variant_);
-    WriteEmbeddedFileSuffix(fp, embedded_variant_);
-
-    fclose(fp);
-  }
-
-  static void WriteEmbeddedFilePrefix(FILE* fp) {
-    fprintf(fp, "// Autogenerated file. Do not edit.\n\n");
-    fprintf(fp, "#include <cstdint>\n\n");
-    fprintf(fp, "#include \"src/snapshot/macros.h\"\n\n");
-    fprintf(fp, "namespace v8 {\n");
-    fprintf(fp, "namespace internal {\n\n");
-    fprintf(fp, "namespace {\n\n");
-  }
-
-  static void WriteEmbeddedFileSuffix(FILE* fp, const char* embedded_variant) {
-    fprintf(fp, "}  // namespace\n\n");
-    fprintf(fp,
-            "const uint8_t* %sEmbeddedBlob() { return "
-            "v8_%s_embedded_blob_; }\n",
-            embedded_variant, embedded_variant);
-    fprintf(fp,
-            "uint32_t %sEmbeddedBlobSize() { return "
-            "v8_embedded_blob_size_; }\n\n",
-            embedded_variant);
-    fprintf(fp, "}  // namespace internal\n");
-    fprintf(fp, "}  // namespace v8\n");
-  }
-
-  static void WriteEmbeddedFileData(FILE* fp, const i::EmbeddedData* blob,
-                                    const char* embedded_variant) {
-    fprintf(fp, "V8_EMBEDDED_TEXT_HEADER(v8_%s_embedded_blob_)\n",
-            embedded_variant);
-#ifdef V8_OS_MACOSX
-    // Note: On some platforms (observed on mac64), inserting labels into the
-    // .byte stream causes the compiler to reorder symbols, invalidating stored
-    // offsets.
-    // We either need to avoid doing so, or stop relying on our own offset table
-    // and directly reference symbols instead. But there is another complication
-    // there since the chrome build process on mac verifies the order of symbols
-    // present in the binary.
-    // For now, the straight-forward solution seems to be to just emit a pure
-    // .byte stream on OSX.
-    WriteBinaryContentsAsInlineAssembly(fp, blob->data(), blob->size());
-#else
-    WriteBinaryContentsAsInlineAssembly(fp, blob->data(),
-                                        i::EmbeddedData::RawDataOffset());
-    WriteBuiltins(fp, blob, embedded_variant);
-#endif
-    fprintf(fp, "extern \"C\" const uint8_t v8_%s_embedded_blob_[];\n",
-            embedded_variant);
-    fprintf(fp, "static const uint32_t v8_embedded_blob_size_ = %d;\n\n",
-            blob->size());
-  }
-
-  static void WriteBuiltins(FILE* fp, const i::EmbeddedData* blob,
-                            const char* embedded_variant) {
-    const bool is_default_variant =
-        std::strcmp(embedded_variant, "Default") == 0;
-    for (int i = 0; i < i::Builtins::builtin_count; i++) {
-      if (!blob->ContainsBuiltin(i)) continue;
-
-      // Labels created here will show up in backtraces. We check in
-      // Isolate::SetEmbeddedBlob that the blob layout remains unchanged, i.e.
-      // that labels do not insert bytes into the middle of the blob byte
-      // stream.
-      if (is_default_variant) {
-        // Create nicer symbol names for the default mode.
-        fprintf(fp, "__asm__(V8_ASM_DECLARE_FUNCTION(\"Builtins_%s\"));\n",
-                i::Builtins::name(i));
-      } else {
-        fprintf(fp, "__asm__(V8_ASM_DECLARE_FUNCTION(\"%s_Builtins_%s\"));\n",
-                embedded_variant, i::Builtins::name(i));
-      }
-
-      WriteBinaryContentsAsInlineAssembly(
-          fp,
-          reinterpret_cast<const uint8_t*>(blob->InstructionStartOfBuiltin(i)),
-          blob->PaddedInstructionSizeOfBuiltin(i));
-    }
-    fprintf(fp, "\n");
-  }
-
-  static int WriteOcta(FILE* fp, int current_line_length, const uint8_t* data) {
-    const uint64_t* quad_ptr1 = reinterpret_cast<const uint64_t*>(data);
-    const uint64_t* quad_ptr2 = reinterpret_cast<const uint64_t*>(data + 8);
-
-#ifdef V8_TARGET_BIG_ENDIAN
-    uint64_t part1 = *quad_ptr1;
-    uint64_t part2 = *quad_ptr2;
-#else
-    uint64_t part1 = *quad_ptr2;
-    uint64_t part2 = *quad_ptr1;
-#endif  // V8_TARGET_BIG_ENDIAN
-
-    if (part1 != 0) {
-      current_line_length +=
-          fprintf(fp, "0x%" PRIx64 "%016" PRIx64, part1, part2);
-    } else {
-      current_line_length += fprintf(fp, "0x%" PRIx64, part2);
-    }
-    return current_line_length;
-  }
-
-  static int WriteDirectiveOrSeparator(FILE* fp, int current_line_length,
-                                       const char* directive) {
-    int printed_chars;
-    if (current_line_length == 0) {
-      printed_chars = fprintf(fp, "  \"%s ", directive);
-      DCHECK_LT(0, printed_chars);
-    } else {
-      printed_chars = fprintf(fp, ",");
-      DCHECK_EQ(1, printed_chars);
-    }
-    return current_line_length + printed_chars;
-  }
-
-  static int WriteLineEndIfNeeded(FILE* fp, int current_line_length,
-                                  int write_size) {
-    static const int kTextWidth = 80;
-    // Check if adding ',0xFF...FF\n"' would force a line wrap. This doesn't use
-    // the actual size of the string to be written to determine this so it's
-    // more conservative than strictly needed.
-    if (current_line_length + strlen(",0x\\n\"") + write_size * 2 >
-        kTextWidth) {
-      fprintf(fp, "\\n\"\n");
-      return 0;
-    } else {
-      return current_line_length;
-    }
-  }
-
-  static void WriteBinaryContentsAsInlineAssembly(FILE* fp, const uint8_t* data,
-                                                  uint32_t size) {
-    int current_line_length = 0;
-
-    fprintf(fp, "__asm__(\n");
-    uint32_t i = 0;
-    const uint32_t size_of_octa = 16;
-    for (; i <= size - size_of_octa; i += size_of_octa) {
-      current_line_length =
-          WriteDirectiveOrSeparator(fp, current_line_length, ".octa");
-      current_line_length = WriteOcta(fp, current_line_length, data + i);
-      current_line_length =
-          WriteLineEndIfNeeded(fp, current_line_length, size_of_octa);
-    }
-    if (current_line_length != 0) fprintf(fp, "\\n\"\n");
-    current_line_length = 0;
-    for (; i < size; i++) {
-      current_line_length =
-          WriteDirectiveOrSeparator(fp, current_line_length, ".byte");
-      current_line_length += fprintf(fp, "0x%x", data[i]);
-      current_line_length = WriteLineEndIfNeeded(fp, current_line_length, 1);
-    }
-    if (current_line_length != 0) fprintf(fp, "\\n\"\n");
-    fprintf(fp, ");\n");
-  }
-
   static FILE* GetFileDescriptorOrDie(const char* filename) {
     FILE* fp = v8::base::OS::FOpen(filename, "wb");
     if (fp == nullptr) {
@@ -289,10 +112,8 @@ class SnapshotWriter {
     return fp;
   }
 
-  const char* embedded_cpp_path_ = nullptr;
-  const char* embedded_variant_ = "Default";
-  const char* snapshot_cpp_path_;
-  const char* snapshot_blob_path_;
+  const char* snapshot_cpp_path_ = nullptr;
+  const char* snapshot_blob_path_ = nullptr;
 };
 
 char* GetExtraCode(char* filename, const char* description) {
@@ -418,7 +239,7 @@ v8::StartupData WarmUpSnapshotDataBlob(v8::SnapshotCreator* snapshot_creator,
   return result;
 }
 
-void WriteEmbeddedFile(SnapshotWriter* writer) {
+void WriteEmbeddedFile(i::EmbeddedFileWriter* writer) {
   i::EmbeddedData embedded_blob = i::EmbeddedData::FromBlob();
   writer->WriteEmbedded(&embedded_blob);
 }
@@ -447,14 +268,13 @@ int main(int argc, char** argv) {
   v8::V8::Initialize();
 
   {
-    SnapshotWriter writer;
-    if (i::FLAG_startup_src) writer.SetSnapshotFile(i::FLAG_startup_src);
-    if (i::FLAG_startup_blob) writer.SetStartupBlobFile(i::FLAG_startup_blob);
-    if (i::FLAG_embedded_builtins) {
-      if (i::FLAG_embedded_src) writer.SetEmbeddedFile(i::FLAG_embedded_src);
-      if (i::FLAG_embedded_variant)
-        writer.SetEmbeddedVariant(i::FLAG_embedded_variant);
-    }
+    SnapshotFileWriter snapshot_writer;
+    snapshot_writer.SetSnapshotFile(i::FLAG_startup_src);
+    snapshot_writer.SetStartupBlobFile(i::FLAG_startup_blob);
+
+    i::EmbeddedFileWriter embedded_writer;
+    embedded_writer.SetEmbeddedFile(i::FLAG_embedded_src);
+    embedded_writer.SetEmbeddedVariant(i::FLAG_embedded_variant);
 
     std::unique_ptr<char> embed_script(
         GetExtraCode(argc >= 2 ? argv[1] : nullptr, "embedding"));
@@ -477,7 +297,7 @@ int main(int argc, char** argv) {
         i_isolate->heap()->ConfigureHeap(0, 0, code_range_size);
       }
       v8::SnapshotCreator snapshot_creator(isolate);
-      if (i::FLAG_embedded_builtins) WriteEmbeddedFile(&writer);
+      if (i::FLAG_embedded_builtins) WriteEmbeddedFile(&embedded_writer);
       blob = CreateSnapshotDataBlob(&snapshot_creator, embed_script.get());
     }
 
@@ -490,7 +310,7 @@ int main(int argc, char** argv) {
     }
 
     CHECK(blob.data);
-    writer.WriteSnapshot(blob);
+    snapshot_writer.WriteSnapshot(blob);
     delete[] blob.data;
   }
   i::FreeCurrentEmbeddedBlob();

test/cctest/BUILD.gn

@@ -196,7 +196,6 @@ v8_source_set("cctest_sources") {
     "test-inobject-slack-tracking.cc",
     "test-inspector.cc",
     "test-intl.cc",
-    "test-isolate-independent-builtins.cc",
     "test-js-weak-refs.cc",
     "test-liveedit.cc",
     "test-lockers.cc",

test/cctest/test-isolate-independent-builtins.cc

-// Copyright 2018 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 "test/cctest/cctest.h"
-
-#include "src/assembler-inl.h"
-#include "src/handles-inl.h"
-#include "src/isolate.h"
-#include "src/macro-assembler-inl.h"
-#include "src/simulator.h"
-#include "src/snapshot/macros.h"
-#include "src/snapshot/snapshot.h"
-#include "test/common/assembler-tester.h"
-
-// To generate the binary files for the test function, enable this section and
-// run GenerateTestFunctionData once on each arch.
-#define GENERATE_TEST_FUNCTION_DATA false
-
-namespace v8 {
-namespace internal {
-namespace test_isolate_independent_builtins {
-
-// V8_CC_MSVC is true for both MSVC and clang on windows. clang can handle
-// __asm__-style inline assembly but MSVC cannot, and thus we need a more
-// precise compiler detection that can distinguish between the two. clang on
-// windows sets both __clang__ and _MSC_VER, MSVC sets only _MSC_VER.
-#if defined(_MSC_VER) && !defined(__clang__)
-#define V8_COMPILER_IS_MSVC
-#endif
-
-#ifndef V8_COMPILER_IS_MSVC
-#if GENERATE_TEST_FUNCTION_DATA
-
-// Arch-specific defines.
-#if V8_TARGET_ARCH_IA32
-#define TEST_FUNCTION_FILE "f-ia32.bin"
-#elif V8_TARGET_ARCH_X64 && _WIN64
-#define TEST_FUNCTION_FILE "f-x64-win.bin"
-#elif V8_TARGET_ARCH_X64
-#define TEST_FUNCTION_FILE "f-x64.bin"
-#elif V8_TARGET_ARCH_ARM64
-#define TEST_FUNCTION_FILE "f-arm64.bin"
-#elif V8_TARGET_ARCH_ARM
-#define TEST_FUNCTION_FILE "f-arm.bin"
-#elif V8_TARGET_ARCH_PPC
-#define TEST_FUNCTION_FILE "f-ppc.bin"
-#elif V8_TARGET_ARCH_MIPS
-#define TEST_FUNCTION_FILE "f-mips.bin"
-#elif V8_TARGET_ARCH_MIPS64
-#define TEST_FUNCTION_FILE "f-mips64.bin"
-#elif V8_TARGET_ARCH_S390
-#define TEST_FUNCTION_FILE "f-s390.bin"
-#else
-#error "Unknown architecture."
-#endif
-
-#define __ masm.
-
-TEST(GenerateTestFunctionData) {
-  CcTest::InitializeVM();
-  Isolate* isolate = CcTest::i_isolate();
-  HandleScope scope(isolate);
-
-#if V8_TARGET_ARCH_IA32
-  v8::internal::byte buffer[256];
-  Assembler masm(isolate, buffer, sizeof(buffer));
-
-  __ mov(eax, Operand(esp, 4));
-  __ add(eax, Operand(esp, 8));
-  __ ret(0);
-#elif V8_TARGET_ARCH_X64
-  size_t allocated;
-  byte* buffer = AllocateAssemblerBuffer(&allocated);
-  Assembler masm(isolate, buffer, static_cast<int>(allocated));
-
-#ifdef _WIN64
-  static const Register arg1 = rcx;
-  static const Register arg2 = rdx;
-#else
-  static const Register arg1 = rdi;
-  static const Register arg2 = rsi;
-#endif
-
-  __ movq(rax, arg2);
-  __ addq(rax, arg1);
-  __ ret(0);
-#elif V8_TARGET_ARCH_ARM64
-  MacroAssembler masm(isolate, nullptr, 0,
-                      v8::internal::CodeObjectRequired::kYes);
-
-  __ Add(x0, x0, x1);
-  __ Ret();
-#elif V8_TARGET_ARCH_ARM
-  Assembler masm(isolate, nullptr, 0);
-
-  __ add(r0, r0, Operand(r1));
-  __ mov(pc, Operand(lr));
-#elif V8_TARGET_ARCH_PPC
-  Assembler masm(isolate, nullptr, 0);
-
-  __ function_descriptor();
-  __ add(r3, r3, r4);
-  __ blr();
-#elif V8_TARGET_ARCH_MIPS
-  MacroAssembler masm(isolate, nullptr, 0,
-                      v8::internal::CodeObjectRequired::kYes);
-
-  __ addu(v0, a0, a1);
-  __ jr(ra);
-  __ nop();
-#elif V8_TARGET_ARCH_MIPS64
-  MacroAssembler masm(isolate, nullptr, 0,
-                      v8::internal::CodeObjectRequired::kYes);
-
-  __ addu(v0, a0, a1);
-  __ jr(ra);
-  __ nop();
-#elif V8_TARGET_ARCH_S390
-  Assembler masm(isolate, nullptr, 0);
-
-  __ agr(r2, r3);
-  __ b(r14);
-#else  // Unknown architecture.
-#error "Unknown architecture."
-#endif  // Target architecture.
-
-  CodeDesc desc;
-  masm.GetCode(isolate, &desc);
-
-  std::ofstream of(TEST_FUNCTION_FILE, std::ios::out | std::ios::binary);
-  of.write(reinterpret_cast<char*>(desc.buffer), desc.instr_size);
-}
-#undef __
-#endif  // GENERATE_TEST_FUNCTION_DATA
-
-#if V8_TARGET_ARCH_IA32
-#define FUNCTION_BYTES \
-  ".byte 0x8b, 0x44, 0x24, 0x04, 0x03, 0x44, 0x24, 0x08, 0xc3\n"
-#elif V8_TARGET_ARCH_X64 && _WIN64
-#define FUNCTION_BYTES ".byte 0x48, 0x8b, 0xc2, 0x48, 0x03, 0xc1, 0xc3\n"
-#elif V8_TARGET_ARCH_X64
-#define FUNCTION_BYTES ".byte 0x48, 0x8b, 0xc6, 0x48, 0x03, 0xc7, 0xc3\n"
-#elif V8_TARGET_ARCH_ARM64
-#define FUNCTION_BYTES ".byte 0x00, 0x00, 0x01, 0x8b, 0xc0, 0x03, 0x5f, 0xd6\n"
-#elif V8_TARGET_ARCH_ARM
-#define FUNCTION_BYTES ".byte 0x01, 0x00, 0x80, 0xe0, 0x0e, 0xf0, 0xa0, 0xe1\n"
-#elif V8_TARGET_ARCH_PPC
-#if defined(V8_OS_AIX)
-#define FUNCTION_BYTES ".byte 0x7c, 0x64, 0x1a, 0x14, 0x4e, 0x80, 0x00, 0x20\n"
-#else
-#define FUNCTION_BYTES ".byte 0x14, 0x22, 0x63, 0x7c, 0x20, 0x00, 0x80, 0x4e\n"
-#endif
-#elif defined(V8_TARGET_ARCH_MIPS) || defined(V8_TARGET_ARCH_MIPS64)
-#if defined(V8_TARGET_BIG_ENDIAN)
-#define FUNCTION_BYTES                               \
-  ".byte 0x00, 0x85, 0x10, 0x21, 0x03, 0xe0, 0x00, " \
-  "0x08, 0x00, 0x00, 0x00, 0x00\n"
-#else
-#define FUNCTION_BYTES                               \
-  ".byte 0x21, 0x10, 0x85, 0x00, 0x08, 0x00, 0xe0, " \
-  "0x03, 0x00, 0x00, 0x00, 0x00\n"
-#endif
-#elif V8_TARGET_ARCH_S390
-#define FUNCTION_BYTES                               \
-  ".byte 0xb9, 0x08, 0x00, 0x23, 0x07, 0xfe\n"
-#else
-#error "Unknown architecture."
-#endif
-
-V8_EMBEDDED_RODATA_HEADER(test_string0_bytes)
-__asm__(".byte 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37\n"
-        ".byte 0x38, 0x39, 0x0a, 0x00\n");
-extern "C" V8_ALIGNED(16) const char test_string0_bytes[];
-
-V8_EMBEDDED_TEXT_HEADER(test_function0_bytes)
-__asm__(FUNCTION_BYTES);
-extern "C" V8_ALIGNED(16) const char test_function0_bytes[];
-// clang-format on
-
-// A historical note: We use .byte over .incbin since the latter leads to
-// complications involving generation of build-time dependencies.  Goma parses
-// #include statements, and clang has -MD/-MMD. Neither recognize .incbin.
-
-TEST(ByteInRodata) {
-  CHECK_EQ(0, std::strcmp("0123456789\n", test_string0_bytes));
-}
-
-TEST(ByteInText) {
-  CcTest::InitializeVM();
-  Isolate* isolate = CcTest::i_isolate();
-  auto f = GeneratedCode<int(int, int)>::FromAddress(
-      isolate, reinterpret_cast<Address>(&test_function0_bytes[0]));
-  CHECK_EQ(7, f.Call(3, 4));
-  CHECK_EQ(11, f.Call(5, 6));
-}
-#endif  // #ifndef V8_COMPILER_IS_MSVC
-#undef V8_COMPILER_IS_MSVC
-
-#undef FUNCTION_BYTES
-#undef GENERATE_TEST_FUNCTION_DATA
-#undef TEST_FUNCTION_FILE
-
-}  // namespace test_isolate_independent_builtins
-}  // namespace internal
-}  // namespace v8