diff options
Diffstat (limited to 'gcc/config/arm/arm.c')
| -rw-r--r-- | gcc/config/arm/arm.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c index 1ac6510..1cc9557 100644 --- a/gcc/config/arm/arm.c +++ b/gcc/config/arm/arm.c @@ -218,6 +218,7 @@ static tree arm_promoted_type (const_tree t); static tree arm_convert_to_type (tree type, tree expr); static bool arm_scalar_mode_supported_p (enum machine_mode); static bool arm_frame_pointer_required (void); +static bool arm_can_eliminate (const int, const int); /* Table of machine attributes. */ @@ -485,6 +486,9 @@ static const struct attribute_spec arm_attribute_table[] = #undef TARGET_FRAME_POINTER_REQUIRED #define TARGET_FRAME_POINTER_REQUIRED arm_frame_pointer_required +#undef TARGET_CAN_ELIMINATE +#define TARGET_CAN_ELIMINATE arm_can_eliminate + struct gcc_target targetm = TARGET_INITIALIZER; /* Obstack for minipool constant handling. */ @@ -14065,6 +14069,24 @@ arm_compute_initial_elimination_offset (unsigned int from, unsigned int to) } } +/* Given FROM and TO register numbers, say whether this elimination is + allowed. Frame pointer elimination is automatically handled. + + All eliminations are permissible. Note that ARG_POINTER_REGNUM and + HARD_FRAME_POINTER_REGNUM are in fact the same thing. If we need a frame + pointer, we must eliminate FRAME_POINTER_REGNUM into + HARD_FRAME_POINTER_REGNUM and not into STACK_POINTER_REGNUM or + ARG_POINTER_REGNUM. */ + +bool +arm_can_eliminate (const int from, const int to) +{ + return ((to == FRAME_POINTER_REGNUM && from == ARG_POINTER_REGNUM) ? false : + (to == STACK_POINTER_REGNUM && frame_pointer_needed) ? false : + (to == ARM_HARD_FRAME_POINTER_REGNUM && TARGET_THUMB) ? false : + (to == THUMB_HARD_FRAME_POINTER_REGNUM && TARGET_ARM) ? false : + true); +} /* Emit RTL to save coprocessor registers on function entry. Returns the number of bytes pushed. */ |