Sets the frame pointer to the current stack frame.
Using the --use_frame_pointer option reserves a register to store the frame pointer.
For newer processors that support Thumb-2 technology (ARMv6T2 and later), the reserved register is always R11.
For older processors that do not support Thumb-2 technology, the reserved register is R11 in ARM code and R7 in Thumb code.
The default is --no_use_frame_pointer. That is, register R11 (or register R7 for Thumb code on older processors) is available for use as a general-purpose register.