arm.c (use_return_insn): Don't reject interrupt functions.

arm.c (use_return_insn): Don't reject interrupt functions.

2002-02-19  Philip Blundell  <philb@gnu.org>

	* config/arm/arm.c (use_return_insn): Don't reject interrupt
	functions.
	(arm_compute_save_reg_mask): Save LR for interrupt functions too.
	(output_return_instruction): Allow interrupt functions to return with
	ldmfd sp!, {... pc}^.  Use LDR to restore any single register.
	(arm_expand_prologue): Subtract 4 before stacking LR in an
	interrupt function.

From-SVN: r49872