[clang] [clang][bytecode] Update high-level documentation (PR #202596)

[Timm Baeder via cfe-commits]

================
@@ -8,12 +8,16 @@ Constant Interpreter
 Introduction
 ============
 
-The constexpr interpreter aims to replace the existing tree evaluator in
+The bytecode interpreter aims to replace the existing tree evaluator in
 clang, improving performance on constructs which are executed inefficiently
 by the evaluator. The interpreter is activated using the following flags:
 
-* ``-fexperimental-new-constant-interpreter`` enables the interpreter,
-  emitting an error if an unsupported feature is encountered
+* ``-fexperimental-new-constant-interpreter`` enables the interpreter.
+
+Since clang 24, the bytecode interpreter can also be enabled by default
----------------
tbaederr wrote:

That's the next major release, isn't it? The flag is there but it needs https://github.com/llvm/llvm-project/pull/200716 to do anything.

https://github.com/llvm/llvm-project/pull/202596