intrinsic's callsite. Variants of the intrinsic with non-void return
type also return a value according to calling convention.
+On PowerPC, note that ``<target>`` must be the ABI function pointer for the
+intended target of the indirect call. Specifically, when compiling for the
+ELF V1 ABI, ``<target>`` is the function-descriptor address normally used as
+the C/C++ function-pointer representation.
+
Requesting zero patch point arguments is valid. In this case, all
variable operands are handled just like
``llvm.experimental.stackmap.*``. The difference is that space will
transformations must not substitute the alloca with any intervening
value. This can be verified by the runtime simply by checking that the
stack map's location is a Direct location type.
+
+
+Supported Architectures
+=======================
+
+Support for StackMap generation and the related intrinsics requires
+some code for each backend. Today, only a subset of LLVM's backends
+are supported. The currently supported architectures are X86_64,
+PowerPC, and Aarch64.
+