+'``llvm.clear_cache``' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+
+::
+
+ declare void @llvm.clear_cache(i8*, i8*)
+
+Overview:
+"""""""""
+
+The '``llvm.clear_cache``' intrinsic provides access to the systemcall
+that flushes the cache at the range specified. Some targets need this
+to specifically flush the instruction cache when executable data changes
+in memory (self-modifying code). Other targets have unified intruction
+and data cache, so they don't need any calls.
+
+Semantics:
+""""""""""
+
+When directly supported, this intrinsic will either return a call to
+the appropriate cache clearing system call (usually ``__clear_cache``)
+when the caches are not unified (ARM, Mips) or just remove the call
+altogether when they are (ex. x86_64). Some targets can lower these
+directly into special instructions, if they have it.
+
+The default behaviour is to emit a call to ``__clear_cache``, so in
+case a target doesn't support it, the user gets a linker error rather
+than a compiler internal error. It also provides a work around to
+the user (implement an empty function called ``__clear_cache``) while
+LLVM doesn't implement it in the target's back-end.
+
+Please note that the caller is responsible for ensuring the cache
+is actually cleared. This is most important in targets that don't
+need to flush the cache directly (ex. x86_64) and could potentially
+still execute old instructions while the cache is not cleared. LLVM
+will *not* insert nops or busy-wait sequences.
+