ffi: add experimental fast FFI call API

Signed-off-by: Paolo Insogna <paolo@cowtech.it>
Assisted-By: OpenAI:GPT-5.5 <openai/gpt-5.5>

Author: ShogunPanda

configure.py

@@ -1059,6 +1059,12 @@
     default=None,
     help='build without FFI (Foreign Function Interface) support')
 
+parser.add_argument('--without-fast-ffi',
+    action='store_true',
+    dest='without_fast_ffi',
+    default=None,
+    help='build without fast FFI support')
+
 parser.add_argument('--experimental-quic',
     action='store_true',
     dest='experimental_quic',
@@ -2330,6 +2336,7 @@ def bundled_ffi_supported(os_name, target_arch):
 
 def configure_ffi(o):
   use_ffi = not options.without_ffi
+  use_fast_ffi = False
 
   if use_ffi and not options.shared_ffi:
     target_arch = o['variables']['target_arch']
@@ -2341,6 +2348,7 @@ def configure_ffi(o):
       use_ffi = False
 
   o['variables']['node_use_ffi'] = b(use_ffi)
+  o['variables']['node_use_fast_ffi'] = b(use_fast_ffi)
 
   if options.without_ffi:
     if options.shared_ffi:
@@ -2352,6 +2360,9 @@ def configure_ffi(o):
 
   configure_library('ffi', o, pkgname='libffi')
 
+  use_fast_ffi = not options.without_fast_ffi and not options.shared_ffi
+  o['variables']['node_use_fast_ffi'] = b(use_fast_ffi)
+
 def configure_quic(o):
   o['variables']['node_use_quic'] = b(options.experimental_quic and
                                       not options.without_ssl)

deps/crates/Cargo.lock

@@ -10,11 +10,17 @@ rust-version = "1.82"
 [lib]
 crate-type = ["staticlib"]
 
+[features]
+fast_ffi = ["dep:cranelift", "dep:cranelift-native", "dep:memmap2"]
+
 [dependencies]
+cranelift = { version = "0.116.1", optional = true }
+cranelift-native = { version = "0.116.1", optional = true }
 # Pin all temporal dependencies to the last version support rustc 1.82
 icu_collections = "~2.0.0"
 icu_locale_core = "~2.0.0"
 icu_provider = "~2.0.0"
+memmap2 = { version = "0.9.9", optional = true }
 timezone_provider = "=0.1.0"
 
 [dependencies.temporal_capi]