diff options
Diffstat (limited to 'gcc/rtl.h')
| -rw-r--r-- | gcc/rtl.h | 52 |
1 files changed, 47 insertions, 5 deletions
@@ -2006,8 +2006,53 @@ enum global_rtl_index GR_MAX }; -/* Pointers to standard pieces of rtx are stored here. */ -extern GTY(()) rtx global_rtl[GR_MAX]; +/* Target-dependent globals. */ +struct GTY(()) target_rtl { + /* All references to the hard registers in global_rtl_index go through + these unique rtl objects. On machines where the frame-pointer and + arg-pointer are the same register, they use the same unique object. + + After register allocation, other rtl objects which used to be pseudo-regs + may be clobbered to refer to the frame-pointer register. + But references that were originally to the frame-pointer can be + distinguished from the others because they contain frame_pointer_rtx. + + When to use frame_pointer_rtx and hard_frame_pointer_rtx is a little + tricky: until register elimination has taken place hard_frame_pointer_rtx + should be used if it is being set, and frame_pointer_rtx otherwise. After + register elimination hard_frame_pointer_rtx should always be used. + On machines where the two registers are same (most) then these are the + same. */ + rtx x_global_rtl[GR_MAX]; + + /* A unique representation of (REG:Pmode PIC_OFFSET_TABLE_REGNUM). */ + rtx x_pic_offset_table_rtx; + + /* A unique representation of (REG:Pmode RETURN_ADDRESS_POINTER_REGNUM). + This is used to implement __builtin_return_address for some machines; + see for instance the MIPS port. */ + rtx x_return_address_pointer_rtx; + + /* Commonly used RTL for hard registers. These objects are not + necessarily unique, so we allocate them separately from global_rtl. + They are initialized once per compilation unit, then copied into + regno_reg_rtx at the beginning of each function. */ + rtx x_initial_regno_reg_rtx[FIRST_PSEUDO_REGISTER]; +}; + +extern GTY(()) struct target_rtl default_target_rtl; +#if SWITCHABLE_TARGET +extern struct target_rtl *this_target_rtl; +#else +#define this_target_rtl (&default_target_rtl) +#endif + +#define global_rtl \ + (this_target_rtl->x_global_rtl) +#define pic_offset_table_rtx \ + (this_target_rtl->x_pic_offset_table_rtx) +#define return_address_pointer_rtx \ + (this_target_rtl->x_return_address_pointer_rtx) /* Standard pieces of rtx, to be substituted directly into things. */ #define pc_rtx (global_rtl[GR_PC]) @@ -2021,9 +2066,6 @@ extern GTY(()) rtx global_rtl[GR_MAX]; #define hard_frame_pointer_rtx (global_rtl[GR_HARD_FRAME_POINTER]) #define arg_pointer_rtx (global_rtl[GR_ARG_POINTER]) -extern GTY(()) rtx pic_offset_table_rtx; -extern GTY(()) rtx return_address_pointer_rtx; - /* Include the RTL generation functions. */ #ifndef GENERATOR_FILE |