arm.c (use_return_insn): New argument, SIBLING.

arm.c (use_return_insn): New argument, SIBLING.

* arm.c (use_return_insn): New argument, SIBLING.  Support returning
with a single instruction if the stack has been decremented by 4
and we have a frame pointer.  Update all callers.
(output_return_instruction): Likewise.
(arm_output_epilogue): Change argument to SIBLING.  Calculate
really_return from the new argument.  Update all callers.
* arm.h (USE_RETURN_INSN): Pass NULL for the sibling.
* arm.md (sibcall_epilogue): Call use_return_insn directly, and
pass the sibling call.
* arm-protos.h (use_return_insn, arm_output_epilogue): Update
prototypes.

From-SVN: r73761