// 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_WASM_WASM_FEATURE_FLAGS_H_
#define V8_WASM_WASM_FEATURE_FLAGS_H_
#if !V8_ENABLE_WEBASSEMBLY
#error This header should only be included if WebAssembly is enabled.
#endif // !V8_ENABLE_WEBASSEMBLY
// Each entry in this file generates a V8 command-line flag with the prefix
// "--experimental-wasm-".
//
// For example, to enable "my_feature", pass
// --experimental-wasm-my-feature to d8, or
// --js-flags=--experimental-wasm-my-feature to Chrome.
//
// To disable "my_feature", add the "--no-" prefix:
// --no-experimental-wasm-my-feature.
//
// See https://github.com/WebAssembly/proposals for an overview of current
// WebAssembly proposals.
// Experimental features (disabled by default).
#define FOREACH_WASM_EXPERIMENTAL_FEATURE_FLAG(V) /* (force 80 columns) */ \
/* Type reflection proposal. */ \
/* https://github.com/webassembly/js-types */ \
/* V8 side owner: ahaas */ \
/* Staged in v7.8, unstaged in v13.6 (see https://crbug.com/402340845) */ \
V(type_reflection, "wasm type reflection in JS", false) \
\
/* Instruction Tracing tool convention (early prototype, might change) */ \
/* Tool convention: https://github.com/WebAssembly/tool-conventions */ \
/* V8 side owner: jabraham */ \
V(instruction_tracing, "instruction tracing section", false) \
\
\
/* Shared-Everything Threads proposal. */ \
/* https://github.com/WebAssembly/shared-everything-threads */ \
/* V8 side owner: manoskouk */ \
V(shared, "shared-everything threads", false) \
\
/* FP16 proposal. */ \
/* https://github.com/WebAssembly/half-precision */ \
/* V8 side owner: irezvov */ \
V(fp16, "fp16", false) \
\
/* Memory Control proposal */ \
/* https://github.com/WebAssembly/memory-control */ \
/* V8 side owner: ahaas */ \
V(memory_control, "memory control", false) \
\
/* Core stack switching, main proposal */ \
/* https://github.com/WebAssembly/stack-switching */ \
/* V8 side owner: fgm */ \
V(wasmfx, "core stack switching", false) \
\
/* Compilation hints */ \
/* https://github.com/WebAssembly/compilation-hints */ \
/* V8 side owner: ecmziegler, manoskouk */ \
V(compilation_hints, "compilation hints", false) \
\
/* V8 side owner: thibaudm */ \
V(growable_stacks, "growable stacks for jspi", false)
// #############################################################################
// Pre-staged features (disabled by default, but enabled via
// --experimental-fuzzing). Pre-staged features get limited fuzzer coverage, and
// should come with their own tests. Features typically spend about 2-4 weeks in
// this stage before being moved to the staging phase. It's therefore expected
// that this list is empty most of the time and that features spend extended
// time right before or after this phase.
#define FOREACH_WASM_PRE_STAGING_FEATURE_FLAG(V) /* (force 80 columns) */ \
/* Custom Descriptors proposal. */ \
/* https://github.com/WebAssembly/custom-descriptors */ \
/* Note: the JS Interop part of the proposal is enabled by */ \
/* --experimental-wasm-js-interop for now. */ \
/* V8 side owner: jkummerow */ \
V(custom_descriptors, "custom descriptors", false) \
// add pre-staged features right before this line
// #############################################################################
// Staged features (disabled by default, but enabled via --wasm-staging (also
// exposed as chrome://flags/#enable-experimental-webassembly-features). Staged
// features get limited fuzzer coverage, and should come with their own tests.
// They are not run through all fuzzers though and don't get much exposure in
// the wild. Staged features are not necessarily fully stabilized. They should
// be shipped with enough lead time to the next branch to allow for
// stabilization.
// Consider adding a chromium-side use counter if you want to track usage in the
// wild (also see {V8::UseCounterFeature}).
#define FOREACH_WASM_STAGING_FEATURE_FLAG(V) /* (force 80 columns) */ \
/* Reference-Typed Strings Proposal. */ \
/* https://github.com/WebAssembly/stringref */ \
/* V8 side owner: jkummerow */ \
V(stringref, "reference-typed strings", false) \
\
/* Imported Strings TextEncoder/TextDecoder post-MVP extension. */ \
/* No upstream repo yet. */ \
/* V8 side owner: jkummerow */ \
V(imported_strings_utf8, "imported strings (utf8 features)", false)
// #############################################################################
// Shipped features (enabled by default). Remove the feature flag once they hit
// stable and are expected to stay enabled.
#define FOREACH_WASM_SHIPPED_FEATURE_FLAG(V) /* (force 80 columns) */ \
/* Legacy exception handling proposal. */ \
/* https://github.com/WebAssembly/exception-handling */ \
/* V8 side owner: thibaudm */ \
/* Staged in v8.9 */ \
/* Shipped in v9.5 */ \
V(legacy_eh, "legacy exception handling opcodes", true) \
\
/* Branch Hinting proposal. */ \
/* https://github.com/WebAssembly/branch-hinting */ \
/* V8 side owner: jkummerow */ \
/* Staged in v13.6. */ \
/* Shipped in v13.7. */ \
V(branch_hinting, "branch hinting", true) \
\
/* Exnref */ \
/* This flag enables the new exception handling proposal */ \
/* V8 side owner: thibaudm */ \
/* Shipped in v13.7 */ \
V(exnref, "exnref", true) \
\
/* Resizable buffer integration */ \
/* https://github.com/WebAssembly/spec/issues/1292 */ \
/* V8 side owner: gdeepti */ \
/* Staged in v14.4 */ \
V(rab_integration, "resizable buffers integration", true)
// Combination of all available wasm feature flags.
#define FOREACH_WASM_FEATURE_FLAG(V) \
FOREACH_WASM_EXPERIMENTAL_FEATURE_FLAG(V) \
FOREACH_WASM_PRE_STAGING_FEATURE_FLAG(V) \
FOREACH_WASM_STAGING_FEATURE_FLAG(V) \
FOREACH_WASM_SHIPPED_FEATURE_FLAG(V)
// Consistency check: Experimental and staged features are off by default.
#define CHECK_WASM_FEATURE_OFF_BY_DEFAULT(name, desc, enabled) \
static_assert(enabled == false);
#define CHECK_WASM_FEATURE_ON_BY_DEFAULT(name, desc, enabled) \
static_assert(enabled == true);
FOREACH_WASM_EXPERIMENTAL_FEATURE_FLAG(CHECK_WASM_FEATURE_OFF_BY_DEFAULT)
FOREACH_WASM_PRE_STAGING_FEATURE_FLAG(CHECK_WASM_FEATURE_OFF_BY_DEFAULT)
FOREACH_WASM_STAGING_FEATURE_FLAG(CHECK_WASM_FEATURE_OFF_BY_DEFAULT)
FOREACH_WASM_SHIPPED_FEATURE_FLAG(CHECK_WASM_FEATURE_ON_BY_DEFAULT)
#undef CHECK_WASM_FEATURE_OFF_BY_DEFAULT
#undef CHECK_WASM_FEATURE_ON_BY_DEFAULT
#endif // V8_WASM_WASM_FEATURE_FLAGS_H_