build: fix pointer compression builds

common.gypi

@@ -82,6 +82,7 @@
     'v8_enable_direct_local%': 0,
     'v8_enable_map_packing%': 0,
     'v8_enable_pointer_compression_shared_cage%': 0,
+    'v8_enable_external_code_space%': 0,
     'v8_enable_sandbox%': 0,
     'v8_enable_v8_checks%': 0,
     'v8_enable_zone_compression%': 0,
@@ -115,6 +116,7 @@
       ['target_arch in "arm ia32 mips mipsel"', {
         'v8_enable_pointer_compression': 0,
         'v8_enable_31bit_smis_on_64bit_arch': 0,
+        'v8_enable_external_code_space': 0,
         'v8_enable_sandbox': 0
       }],
       ['target_arch in "ppc64 s390x"', {
@@ -455,6 +457,9 @@
       ['v8_enable_sandbox == 1', {
         'defines': ['V8_ENABLE_SANDBOX',],
       }],
+      ['v8_enable_external_code_space == 1', {
+        'defines': ['V8_EXTERNAL_CODE_SPACE',],
+      }],
       ['v8_deprecation_warnings == 1', {
         'defines': ['V8_DEPRECATION_WARNINGS',],
       }],

configure.py

@@ -1712,7 +1712,15 @@ def configure_v8(o, configs):
   o['variables']['v8_enable_maglev'] = B(not options.v8_disable_maglev and
                                          o['variables']['target_arch'] in maglev_enabled_architectures)
   o['variables']['v8_enable_pointer_compression'] = 1 if options.enable_pointer_compression else 0
-  o['variables']['v8_enable_sandbox'] = 1 if options.enable_pointer_compression else 0
+  # Using the sandbox requires always allocating array buffer backing stores in the sandbox.
+  # We currently have many backing stores tied to pointers from C++ land that are not
+  # even necessarily dynamic (e.g. in static storage) for fast communication between JS and C++.
+  # Until we manage to get rid of all those, v8_enable_sandbox cannot be used.
+  # Note that enabling pointer compression without enabling sandbox is unsupported by V8,
+  # so this can be broken at any time.
+  o['variables']['v8_enable_sandbox'] = 0
+  o['variables']['v8_enable_pointer_compression_shared_cage'] = 1 if options.enable_pointer_compression else 0
+  o['variables']['v8_enable_external_code_space'] = 1 if options.enable_pointer_compression else 0
   o['variables']['v8_enable_31bit_smis_on_64bit_arch'] = 1 if options.enable_pointer_compression else 0
   o['variables']['v8_enable_extensible_ro_snapshot'] = 0
   o['variables']['v8_trace_maps'] = 1 if options.trace_maps else 0

test/cctest/node_test_fixture.cc

@@ -21,9 +21,6 @@ void NodeTestEnvironment::SetUp() {
   NodeZeroIsolateTestFixture::platform.reset(
       new node::NodePlatform(kV8ThreadPoolSize, tracing_controller));
   v8::V8::InitializePlatform(NodeZeroIsolateTestFixture::platform.get());
-#ifdef V8_ENABLE_SANDBOX
-  ASSERT_TRUE(v8::V8::InitializeSandbox());
-#endif
   cppgc::InitializeProcess(
       NodeZeroIsolateTestFixture::platform->GetPageAllocator());
 

test/wasm-allocation/wasm-allocation.status

@@ -6,5 +6,5 @@ prefix wasm-allocation
 
 [true] # This section applies to all platforms
 
-[$system!=linux || $asan==on]
+[$system!=linux || $asan==on || $pointer_compression==on]
 test-wasm-allocation: SKIP

tools/test.py

@@ -1619,6 +1619,9 @@ def get_asan_state(vm, context):
   asan = Execute([vm, '-p', 'process.config.variables.asan'], context).stdout.strip()
   return "on" if asan == "1" else "off"
 
+def get_pointer_compression_state(vm, context):
+  pointer_compression = Execute([vm, '-p', 'process.config.variables.v8_enable_pointer_compression'], context).stdout.strip()
+  return "on" if pointer_compression == "1" else "off"
 
 def Main():
   parser = BuildOptions()
@@ -1717,6 +1720,7 @@ def Main():
           'arch': vmArch,
           'type': get_env_type(vm, options.type, context),
           'asan': get_asan_state(vm, context),
+          'pointer_compression': get_pointer_compression_state(vm, context),
         }
         test_list = root.ListTests([], path, context, arch, mode)
         unclassified_tests += test_list

tools/v8_gypfiles/features.gypi

@@ -248,6 +248,11 @@
     # Sets -DV8_ENABLE_SANDBOX.
     'v8_enable_sandbox%': 0,
 
+    # Enable support for external code range relative to the pointer compression
+    # cage.
+    # Sets -DV8_EXTERNAL_CODE_SPACE.
+    'v8_enable_external_code_space%': 0,
+
     # Experimental feature for collecting per-class zone memory stats.
     # Requires use_rtti = true
     'v8_enable_precise_zone_stats%': 0,
@@ -380,6 +385,9 @@
       ['v8_enable_sandbox==1', {
         'defines': ['V8_ENABLE_SANDBOX',],
       }],
+      ['v8_enable_external_code_space==1', {
+        'defines': ['V8_EXTERNAL_CODE_SPACE',],
+      }],
       ['v8_enable_object_print==1', {
         'defines': ['OBJECT_PRINT',],
       }],