[PATCH] D12498: X86: add an interrupt calling convention

[H.J Lu via llvm-commits]

hjl.tools added a comment.

The current interrupt spec is

https://gcc.gnu.org/ml/gcc-patches/2015-11/msg00641.html

We added:

To be feature complete, compiler may implement the optional
'no_caller_saved_registers' attribute:

Use this attribute to indicate that the specified function has no
caller-saved registers.  That is, all registers are callee-saved.
The compiler generates proper function entry and exit sequences to
save and restore any modified registers.

The user can call functions specified with 'no_caller_saved_registers'
attribute from an interrupt handler without saving and restoring all
call clobbered registers.

H.J.


Repository:
  rL LLVM

http://reviews.llvm.org/D12498