PR target/40657
	* config/arm/arm.c (thumb1_extra_regs_pushed): New function.
	(thumb1_expand_prologue, thumb1_output_function_prologue): Call it
	here to determine which regs to push and how much stack to reserve.

	PR target/40657
	* gcc.target/arm/thumb-stackframe.c: New test.

From-SVN: r158771