PR rtl-optimization/50063
* config/avr/avr.md (movhi_sp_r): Handle -1 (unknown IRQ state)
and 2 (8-bit SP) in operand 2.
* config/avr/avr.c (avr_prologue_setup_frame): Adjust prologue
setup to use movhi_sp_r instead of vanilla move to write SP.
Adjust REG_CFA notes to superseed unspec.
(expand_epilogue): Adjust epilogue setup to use movhi_sp_r instead
of vanilla move.
As function body might contain CLI or SEI: Use irq_state 0 (IRQ
known to be off) only with TARGET_NO_INTERRUPTS. Never use
irq_state 1 (IRQ known to be on) here.
From-SVN: r184461
