Frame pointer not getting eliminated

[William Tambe]

I am doing porting work and writing a backend using GCC 8.2.0.

Despite the following #defines, the frame pointer is not getting
eliminated; any idea why GCC would still generate a frame pointer ?

#undef TARGET_FRAME_POINTER_REQUIRED
#define TARGET_FRAME_POINTER_REQUIRED hook_bool_void_false

#define ELIMINABLE_REGS  \
          {{ARG_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
           {ARG_POINTER_REGNUM, FRAME_POINTER_REGNUM}, \
           {FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}}

#define INITIAL_ELIMINATION_OFFSET(FROM,TO,OFFSET) \
           (OFFSET) = pu32_initial_elimination_offset(FROM, TO)