docs: document `x` mangling in LangRef

Windows has two different mangling specifiers.  `x` is used on x86 for the `_`
UserLabelPrefix.  Others use `w` for the no UserLabelPrefix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251260 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/LangRef.rst b/docs/LangRef.rst
index 2a881d1d6d965dd6e893fea1022928a08c8a3541..388bb6b164203f8fe2929920970994c2a8c2c634 100644 (file)
--- a/docs/LangRef.rst
+++ b/docs/LangRef.rst
@@ -1569,6 +1569,8 @@ as follows:
       symbols get a ``_`` prefix.
     * ``w``: Windows COFF prefix:  Similar to Mach-O, but stdcall and fastcall
       functions also get a suffix based on the frame size.
+    * ``x``: Windows x86 COFF prefix:  Similar to Windows COFF, but use a ``_``
+      prefix for ``__cdecl`` functions.
 ``n<size1>:<size2>:<size3>...``
     This specifies a set of native integer widths for the target CPU in
     bits. For example, it might contain ``n32`` for 32-bit PowerPC,