I have an application where many of the leaf functions are
Hand-coded assembly language, because they use special IO instructions
That only the assembler knows about. These functions typically don’t
Use any registers besides the incoming argument registers, IE they don’t
Need to use any additional callee-save nor caller-save registers.
Is there any way in your IPRA interprocedural register allocation project that
The user can supply this information for external functions ?
Perhaps using some form of attribute ?
Maybe attribute ((registermask = ….)) ?