Merging upstream version 126.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/js/src/jit/TrampolineNatives.h b/js/src/jit/TrampolineNatives.h
new file mode 100644
index 0000000000..f71a3b707d
--- /dev/null
+++ b/js/src/jit/TrampolineNatives.h
@@ -0,0 +1,60 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef jit_TrampolineNatives_h
+#define jit_TrampolineNatives_h
+
+#include <stdint.h>
+
+#include "js/TypeDecls.h"
+
+// [SMDOC] Trampoline Natives
+//
+// Trampoline natives are JS builtin functions that use the NATIVE_JIT_ENTRY
+// mechanism. This means they have two implementations: the usual native C++
+// implementation and a generated JIT trampoline that JIT callers can call
+// directly using the JIT ABI calling convention. (This is very similar to how
+// calls from JS to WebAssembly are optimized in the JITs.)
+//
+// The JIT trampoline lets us implement some natives in a more efficient way. In
+// particular, it's much faster to call (other) JS functions with JIT code from
+// a JIT trampoline than from C++ code.
+//
+// Trampoline frames use FrameType::TrampolineNative.
+
+class JSJitInfo;
+
+namespace JS {
+class CallArgs;
+}  // namespace JS
+
+// List of all trampoline natives.
+#define TRAMPOLINE_NATIVE_LIST(_) _(ArraySort)
+
+namespace js {
+namespace jit {
+
+enum class TrampolineNative : uint16_t {
+#define ADD_NATIVE(native) native,
+  TRAMPOLINE_NATIVE_LIST(ADD_NATIVE)
+#undef ADD_NATIVE
+      Count
+};
+
+#define ADD_NATIVE(native) extern const JSJitInfo JitInfo_##native;
+TRAMPOLINE_NATIVE_LIST(ADD_NATIVE)
+#undef ADD_NATIVE
+
+void SetTrampolineNativeJitEntry(JSContext* cx, JSFunction* fun,
+                                 TrampolineNative native);
+
+bool CallTrampolineNativeJitCode(JSContext* cx, TrampolineNative native,
+                                 JS::CallArgs& args);
+
+}  // namespace jit
+}  // namespace js
+
+#endif /* jit_TrampolineNatives_h */