If we support multiple ABIs in the same translation unit, it can
sometimes be the case that a callee clobbers more registers than
its caller is allowed to. We need to call df_set_regs_ever_live
on these extra registers so that the prologue and epilogue code
can handle them appropriately.
This patch does that in IRA. I wanted to avoid another full
instruction walk just for this, so I combined it with the existing
set_paradoxical_subreg walk. This happens before the first
calculation of elimination offsets.
2019-09-30 Richard Sandiford <richard.sandiford@arm.com>
gcc/
* function-abi.h (function_abi_aggregator): New class.
* function-abi.cc (function_abi_aggregator::caller_save_regs): New
function.
* ira.c (update_equiv_regs_prescan): New function. Call
set_paradoxical_subreg here rather than...
(update_equiv_regs): ...here.
(ira): Call update_equiv_regs_prescan.
From-SVN: r276339
