* tic80-tdep.c, config/tic80/tm-tic80.h: First cut at getting
basic C80 features working.
This commit is contained in:
parent
044c6b40b2
commit
6e12c187ba
3 changed files with 522 additions and 69 deletions
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@ -1,3 +1,8 @@
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Mon May 12 11:35:04 1997 Mark Alexander <marka@cygnus.com>
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* tic80-tdep.c, config/tic80/tm-tic80.h: First cut at getting
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basic C80 features working.
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Thu May 8 08:42:47 1997 Andrew Cagney <cagney@b1.cygnus.com>
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* configure.in (AC_TYPE_SIGNAL): Add
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@ -51,7 +51,11 @@ struct frame_saved_regs;
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FIXME: Shadow updates in sim/tic80/sim-calls.c */
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#define SP_REGNUM 1 /* Contains address of top of stack */
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#define FP_REGNUM 31 /* Contains address of executing stack frame */
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#define ARG0_REGNUM 2 /* Contains argument 1 (r3 has high word) */
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#define RET_REGNUM 2 /* Contains function return value */
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#define ARGLAST_REGNUM 12 /* Contains argument 6 (r13 has high word) */
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#define FP_REGNUM 30 /* Contains address of executing stack frame */
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#define LR_REGNUM 31 /* Contains address of caller (link register) */
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#define PC_REGNUM 32 /* Contains program counter (FIXME?) */
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#define NPC_REGNUM 33 /* Contains the next program counter (FIXME?) */
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#define A0_REGNUM 34 /* Accumulator register 0 */
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@ -119,15 +123,10 @@ struct frame_saved_regs;
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#define DECR_PC_AFTER_BREAK 0 /* FIXME! */
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/* Push an empty stack frame, to record the current PC, etc. */
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#define PUSH_DUMMY_FRAME tic80_push_dummy_frame()
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extern void tic80_push_dummy_frame PARAMS ((void));
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/* Discard from the stack the innermost frame, restoring all registers. */
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#define POP_FRAME tic80_pop_frame()
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extern void tic80_pop_frame PARAMS ((void));
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#define POP_FRAME tic80_pop_frame(get_current_frame ())
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extern struct frame_info *tic80_pop_frame PARAMS ((struct frame_info *frame));
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/* Return number of bytes at start of arglist that are not really args. */
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@ -143,6 +142,22 @@ extern void tic80_pop_frame PARAMS ((void));
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#define FRAME_ARGS_ADDRESS(fi) (fi)->frame
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#define FRAME_LOCALS_ADDRESS(fi) (fi)->frame
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/* Define other aspects of the stack frame.
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We keep the offsets of all saved registers, 'cause we need 'em a lot!
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We also keep the current size of the stack frame, and the offset of
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the frame pointer from the stack pointer (for frameless functions, and
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when we're still in the prologue of a function with a frame) */
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#define EXTRA_FRAME_INFO \
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struct frame_saved_regs fsr; \
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int framesize; \
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int frameoffset; \
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int framereg;
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extern void tic80_init_extra_frame_info PARAMS ((struct frame_info *fi));
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#define INIT_EXTRA_FRAME_INFO(fromleaf, fi) tic80_init_extra_frame_info (fi)
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#define INIT_FRAME_PC /* Not necessary */
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/* Put here the code to store, into a struct frame_saved_regs,
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the addresses of the saved registers of frame described by FRAME_INFO.
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This includes special registers such as pc and fp saved in special
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@ -164,8 +179,7 @@ extern CORE_ADDR tic80_skip_prologue PARAMS ((CORE_ADDR pc));
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the new frame is not set up until the new function executes
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some instructions. */
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#define SAVED_PC_AFTER_CALL(frame) tic80_saved_pc_after_call(frame)
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extern CORE_ADDR tic80_saved_pc_after_call PARAMS ((struct frame_info *));
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#define SAVED_PC_AFTER_CALL(frame) read_register (LR_REGNUM)
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/* Describe the pointer in each stack frame to the previous stack frame
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(its caller). */
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@ -179,19 +193,64 @@ extern CORE_ADDR tic80_frame_chain PARAMS ((struct frame_info *));
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#define FRAME_SAVED_PC(FRAME) tic80_frame_saved_pc (FRAME)
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extern CORE_ADDR tic80_frame_saved_pc PARAMS ((struct frame_info *));
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/* Store the address of the place in which to copy the structure the
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subroutine will return. This is called from call_function.
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We store structs through a pointer passed in R2 */
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#define STORE_STRUCT_RETURN(STRUCT_ADDR, SP) \
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write_register (ARG0_REGNUM, STRUCT_ADDR)
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/* Extract from an array REGBUF containing the (raw) register state
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a function return value of type TYPE, and copy that, in virtual format,
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into VALBUF. */
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#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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tic80_extract_return_value((TYPE), (REGBUF), (VALBUF))
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extern void tic80_extract_return_value PARAMS ((struct type *, char *, char *));
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memcpy ((VALBUF), \
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(char *)(REGBUF) + REGISTER_BYTE (RET_REGNUM) + \
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((TYPE_LENGTH (TYPE) > 4 ? 8 : 4) - TYPE_LENGTH (TYPE)), \
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TYPE_LENGTH (TYPE))
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/* Write into appropriate registers a function return value
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of type TYPE, given in virtual format. */
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#define STORE_RETURN_VALUE(TYPE,VALBUF) \
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tic80_store_return_value((TYPE), (VALBUF))
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extern void tic80_store_return_value PARAMS ((struct type *, char *));
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write_register_bytes(REGISTER_BYTE (RET_REGNUM) + \
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((TYPE_LENGTH (TYPE) > 4 ? 8:4) - TYPE_LENGTH (TYPE)),\
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(VALBUF), TYPE_LENGTH (TYPE));
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/* PUSH_ARGUMENTS */
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extern CORE_ADDR tic80_push_arguments PARAMS ((int nargs,
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struct value **args,
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CORE_ADDR sp,
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unsigned char struct_return,
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CORE_ADDR struct_addr));
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#define PUSH_ARGUMENTS(NARGS, ARGS, SP, STRUCT_RETURN, STRUCT_ADDR) \
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(SP) = tic80_push_arguments (NARGS, ARGS, SP, STRUCT_RETURN, STRUCT_ADDR)
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/* PUSH_RETURN_ADDRESS */
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extern CORE_ADDR tic80_push_return_address PARAMS ((CORE_ADDR, CORE_ADDR));
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#define PUSH_RETURN_ADDRESS(PC, SP) tic80_push_return_address (PC, SP)
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/* override the standard get_saved_register function with
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one that takes account of generic CALL_DUMMY frames */
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#define GET_SAVED_REGISTER
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#define USE_GENERIC_DUMMY_FRAMES
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#define CALL_DUMMY {0}
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#define CALL_DUMMY_LENGTH (0)
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#define CALL_DUMMY_START_OFFSET (0)
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#define CALL_DUMMY_BREAKPOINT_OFFSET (0)
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#define FIX_CALL_DUMMY(DUMMY1, STARTADDR, FUNADDR, NARGS, ARGS, TYPE, GCCP)
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#define CALL_DUMMY_LOCATION AT_ENTRY_POINT
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#define CALL_DUMMY_ADDRESS() entry_point_address ()
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/* generic dummy frame stuff */
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#define PUSH_DUMMY_FRAME generic_push_dummy_frame ()
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#define PC_IN_CALL_DUMMY(PC, SP, FP) generic_pc_in_call_dummy (PC, SP)
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#endif /* TM_TIC80_H */
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499
gdb/tic80-tdep.c
499
gdb/tic80-tdep.c
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@ -1,6 +1,5 @@
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/* Target-dependent code for the TI TMS320C80 (MVP) architecture,
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for GDB, the GNU Debugger.
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Copyright 1997 Free Software Foundation, Inc.
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/* Target-dependent code for the TI TMS320C80 (MVP) for GDB, the GNU debugger.
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Copyright 1996, Free Software Foundation, Inc.
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This file is part of GDB.
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@ -19,71 +18,461 @@ along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "value.h"
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#include "frame.h"
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#include "inferior.h"
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#include "obstack.h"
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#include "target.h"
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#include "bfd.h"
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#include "gdb_string.h"
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#include "gdbcore.h"
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#include "symfile.h"
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/* Function: frame_find_saved_regs
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Return the frame_saved_regs structure for the frame.
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Doesn't really work for dummy frames, but it does pass back
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an empty frame_saved_regs, so I guess that's better than total failure */
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void
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tic80_frame_find_saved_regs (fi, regaddr)
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struct frame_info *fi;
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struct frame_saved_regs *regaddr;
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{
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memcpy (regaddr, &fi->fsr, sizeof (struct frame_saved_regs));
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}
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/* Function: skip_prologue
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Find end of function prologue. */
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CORE_ADDR
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tic80_skip_prologue (pc)
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CORE_ADDR pc;
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{
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error ("tic80_skip_prologue not implemented");
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CORE_ADDR func_addr, func_end;
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struct symtab_and_line sal;
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/* See what the symbol table says */
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if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
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{
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sal = find_pc_line (func_addr, 0);
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if (sal.line != 0 && sal.end < func_end)
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return sal.end;
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else
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/* Either there's no line info, or the line after the prologue is after
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the end of the function. In this case, there probably isn't a
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prologue. */
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return pc;
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}
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/* We can't find the start of this function, so there's nothing we can do. */
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return pc;
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}
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CORE_ADDR
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tic80_frame_chain (finfo)
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struct frame_info *finfo;
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{
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error ("tic80_frame_chain not implemented");
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}
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/* Function: tic80_scan_prologue
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This function decodes the target function prologue to determine:
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1) the size of the stack frame
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2) which registers are saved on it
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3) the offsets of saved regs
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4) the frame size
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This information is stored in the "extra" fields of the frame_info. */
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CORE_ADDR
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tic80_frame_saved_pc (finfo)
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struct frame_info *finfo;
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{
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error ("tic80_frame_saved_pc not implemented");
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}
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CORE_ADDR
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tic80_saved_pc_after_call (finfo)
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struct frame_info *finfo;
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{
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error ("tic80_saved_pc_after_call not implemented");
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}
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void
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tic80_pop_frame ()
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{
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error ("tic80_pop_frame not implemented");
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}
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void
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tic80_store_return_value (valtype, valbuf)
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struct type *valtype;
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char *valbuf;
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{
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error ("tic80_store_return_value not implemented");
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}
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/* Put here the code to store, into a struct frame_saved_regs, the
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addresses of the saved registers of frame described by FRAME_INFO.
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This includes special registers such as pc and fp saved in special
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ways in the stack frame. sp is even more special: the address we
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return for it IS the sp for the next frame. */
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void
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tic80_frame_find_saved_regs (fi, fsr)
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static void
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tic80_scan_prologue (fi)
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struct frame_info *fi;
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struct frame_saved_regs *fsr;
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{
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error ("tic80_frame_find_saved_regs not implemented");
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struct symtab_and_line sal;
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CORE_ADDR prologue_start, prologue_end, current_pc;
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/* Assume there is no frame until proven otherwise. */
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fi->framereg = SP_REGNUM;
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fi->framesize = 0;
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fi->frameoffset = 0;
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/* this code essentially duplicates skip_prologue,
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but we need the start address below. */
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if (find_pc_partial_function (fi->pc, NULL, &prologue_start, &prologue_end))
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{
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sal = find_pc_line (prologue_start, 0);
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if (sal.line == 0) /* no line info, use current PC */
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if (prologue_start != entry_point_address ())
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prologue_end = fi->pc;
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else
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return; /* _start has no frame or prologue */
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else if (sal.end < prologue_end) /* next line begins after fn end */
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prologue_end = sal.end; /* (probably means no prologue) */
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}
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else
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/* FIXME */
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prologue_end = prologue_start + 40; /* We're in the boondocks: allow for */
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/* 16 pushes, an add, and "mv fp,sp" */
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prologue_end = min (prologue_end, fi->pc);
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/* Now search the prologue looking for instructions that set up the
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frame pointer, adjust the stack pointer, and save registers. */
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for (current_pc = prologue_start; current_pc < prologue_end; current_pc += 4)
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{
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unsigned int insn;
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int regno;
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int offset = 0;
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insn = read_memory_unsigned_integer (current_pc, 4);
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if ((insn & 0x301000) == 0x301000) /* Long immediate? */
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/* FIXME - set offset for long immediate instructions */
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current_pc += 4;
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else
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{
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offset = insn & 0x7fff; /* extract 15-bit offset */
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if (offset & 0x4000) /* if negative, sign-extend */
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offset = -(0x8000 - offset);
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}
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if ((insn & 0x7fd0000) == 0x590000) /* st.{w,d} reg, xx(r1) */
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{
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regno = ((insn >> 27) & 0x1f);
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fi->fsr.regs[regno] = offset;
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if (insn & 0x8000) /* 64-bit store (st.d)? */
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fi->fsr.regs[regno+1] = offset+4;
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}
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else if ((insn & 0xffff8000) == 0x086c8000) /* addu xx, r1, r1 */
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fi->framesize = -offset;
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else if ((insn & 0xffff8000) == 0xf06c8000) /* addu xx, r1, r30 */
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{
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fi->framereg = FP_REGNUM; /* fp is now valid */
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fi->frameoffset = offset;
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break; /* end of stack adjustments */
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}
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else if (insn == 0xf03b2001) /* addu r1, r0, r30 */
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{
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fi->framereg = FP_REGNUM; /* fp is now valid */
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fi->frameoffset = 0;
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break; /* end of stack adjustments */
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}
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else
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/* FIXME - handle long immediate instructions */
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break; /* anything else isn't prologue */
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}
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}
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/* Given a return value in `regbuf' with a type `valtype',
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extract and copy its value into `valbuf'. */
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/* Function: init_extra_frame_info
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This function actually figures out the frame address for a given pc and
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sp. This is tricky on the c80 because we sometimes don't use an explicit
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frame pointer, and the previous stack pointer isn't necessarily recorded
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on the stack. The only reliable way to get this info is to
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examine the prologue. */
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void
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tic80_extract_return_value (valtype, regbuf, valbuf)
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struct type *valtype;
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char regbuf[REGISTER_BYTES];
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char *valbuf;
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tic80_init_extra_frame_info (fi)
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struct frame_info *fi;
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{
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error ("tic80_extract_return_value not implemented");
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int reg;
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if (fi->next)
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fi->pc = FRAME_SAVED_PC (fi->next);
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memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs);
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if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
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{
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/* We need to setup fi->frame here because run_stack_dummy gets it wrong
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by assuming it's always FP. */
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fi->frame = generic_read_register_dummy (fi->pc, fi->frame, SP_REGNUM);
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fi->framesize = 0;
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fi->frameoffset = 0;
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return;
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}
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else
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{
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tic80_scan_prologue (fi);
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if (!fi->next) /* this is the innermost frame? */
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fi->frame = read_register (fi->framereg);
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else /* not the innermost frame */
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if (fi->framereg == FP_REGNUM) /* we have an FP */
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if (fi->next->fsr.regs[FP_REGNUM] != 0) /* caller saved our FP */
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fi->frame = read_memory_integer (fi->next->fsr.regs[FP_REGNUM], 4);
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for (reg = 0; reg < NUM_REGS; reg++)
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if (fi->fsr.regs[reg] != 0)
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fi->fsr.regs[reg] += fi->frame - fi->frameoffset;
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}
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}
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/* Function: find_callers_reg
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Find REGNUM on the stack. Otherwise, it's in an active register. One thing
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we might want to do here is to check REGNUM against the clobber mask, and
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somehow flag it as invalid if it isn't saved on the stack somewhere. This
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would provide a graceful failure mode when trying to get the value of
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caller-saves registers for an inner frame. */
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CORE_ADDR
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tic80_find_callers_reg (fi, regnum)
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struct frame_info *fi;
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int regnum;
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{
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for (; fi; fi = fi->next)
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if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame))
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return generic_read_register_dummy (fi->pc, fi->frame, regnum);
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else if (fi->fsr.regs[regnum] != 0)
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return read_memory_integer (fi->fsr.regs[regnum],
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REGISTER_RAW_SIZE(regnum));
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return read_register (regnum);
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}
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/* Function: frame_chain
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Given a GDB frame, determine the address of the calling function's frame.
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This will be used to create a new GDB frame struct, and then
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INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
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For c80, we save the frame size when we initialize the frame_info. */
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CORE_ADDR
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tic80_frame_chain (fi)
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struct frame_info *fi;
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{
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CORE_ADDR fn_start, callers_pc, fp;
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/* is this a dummy frame? */
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if (PC_IN_CALL_DUMMY(fi->pc, fi->frame, fi->frame))
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return fi->frame; /* dummy frame same as caller's frame */
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/* is caller-of-this a dummy frame? */
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callers_pc = FRAME_SAVED_PC(fi); /* find out who called us: */
|
||||
fp = tic80_find_callers_reg (fi, FP_REGNUM);
|
||||
if (PC_IN_CALL_DUMMY(callers_pc, fp, fp))
|
||||
return fp; /* dummy frame's frame may bear no relation to ours */
|
||||
|
||||
if (find_pc_partial_function (fi->pc, 0, &fn_start, 0))
|
||||
if (fn_start == entry_point_address ())
|
||||
return 0; /* in _start fn, don't chain further */
|
||||
|
||||
if (fi->framereg == FP_REGNUM)
|
||||
return tic80_find_callers_reg (fi, FP_REGNUM);
|
||||
else
|
||||
return fi->frame + fi->framesize;
|
||||
}
|
||||
|
||||
/* Function: pop_frame
|
||||
Discard from the stack the innermost frame,
|
||||
restoring all saved registers. */
|
||||
|
||||
struct frame_info *
|
||||
tic80_pop_frame (frame)
|
||||
struct frame_info *frame;
|
||||
{
|
||||
int regnum;
|
||||
|
||||
if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
|
||||
generic_pop_dummy_frame ();
|
||||
else
|
||||
{
|
||||
for (regnum = 0; regnum < NUM_REGS; regnum++)
|
||||
if (frame->fsr.regs[regnum] != 0)
|
||||
write_register (regnum,
|
||||
read_memory_integer (frame->fsr.regs[regnum], 4));
|
||||
|
||||
write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
|
||||
write_register (SP_REGNUM, read_register (FP_REGNUM));
|
||||
#if 0
|
||||
if (read_register (PSW_REGNUM) & 0x80)
|
||||
write_register (SPU_REGNUM, read_register (SP_REGNUM));
|
||||
else
|
||||
write_register (SPI_REGNUM, read_register (SP_REGNUM));
|
||||
#endif
|
||||
}
|
||||
flush_cached_frames ();
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Function: frame_saved_pc
|
||||
Find the caller of this frame. We do this by seeing if LR_REGNUM is saved
|
||||
in the stack anywhere, otherwise we get it from the registers. */
|
||||
|
||||
CORE_ADDR
|
||||
tic80_frame_saved_pc (fi)
|
||||
struct frame_info *fi;
|
||||
{
|
||||
if (PC_IN_CALL_DUMMY(fi->pc, fi->frame, fi->frame))
|
||||
return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM);
|
||||
else
|
||||
return tic80_find_callers_reg (fi, LR_REGNUM);
|
||||
}
|
||||
|
||||
/* Function: tic80_push_return_address (pc, sp)
|
||||
Set up the return address for the inferior function call.
|
||||
Necessary for targets that don't actually execute a JSR/BSR instruction
|
||||
(ie. when using an empty CALL_DUMMY) */
|
||||
|
||||
CORE_ADDR
|
||||
tic80_push_return_address (pc, sp)
|
||||
CORE_ADDR pc;
|
||||
CORE_ADDR sp;
|
||||
{
|
||||
write_register (LR_REGNUM, CALL_DUMMY_ADDRESS ());
|
||||
return sp;
|
||||
}
|
||||
|
||||
|
||||
/* Function: push_arguments
|
||||
Setup the function arguments for calling a function in the inferior.
|
||||
|
||||
On the TI C80 architecture, there are six register pairs (R2/R3 to R12/13)
|
||||
which are dedicated for passing function arguments. Up to the first six
|
||||
arguments (depending on size) may go into these registers.
|
||||
The rest go on the stack.
|
||||
|
||||
Arguments that are smaller than 4 bytes will still take up a whole
|
||||
register or a whole 32-bit word on the stack, and will be
|
||||
right-justified in the register or the stack word. This includes
|
||||
chars, shorts, and small aggregate types.
|
||||
|
||||
Arguments that are four bytes or less in size are placed in the
|
||||
even-numbered register of a register pair, and the odd-numbered
|
||||
register is not used.
|
||||
|
||||
Arguments of 8 bytes size (such as floating point doubles) are placed
|
||||
in a register pair. The least significant 32-bit word is placed in
|
||||
the even-numbered register, and the most significant word in the
|
||||
odd-numbered register.
|
||||
|
||||
Aggregate types with sizes between 4 and 8 bytes are passed
|
||||
entirely on the stack, and are left-justified within the
|
||||
double-word (as opposed to aggregates smaller than 4 bytes
|
||||
which are right-justified).
|
||||
|
||||
Aggregates of greater than 8 bytes are first copied onto the stack,
|
||||
and then a pointer to the copy is passed in the place of the normal
|
||||
argument (either in a register if available, or on the stack).
|
||||
|
||||
Functions that must return an aggregate type can return it in the
|
||||
normal return value registers (R2 and R3) if its size is 8 bytes or
|
||||
less. For larger return values, the caller must allocate space for
|
||||
the callee to copy the return value to. A pointer to this space is
|
||||
passed as an implicit first argument, always in R0. */
|
||||
|
||||
CORE_ADDR
|
||||
tic80_push_arguments (nargs, args, sp, struct_return, struct_addr)
|
||||
int nargs;
|
||||
value_ptr *args;
|
||||
CORE_ADDR sp;
|
||||
unsigned char struct_return;
|
||||
CORE_ADDR struct_addr;
|
||||
{
|
||||
int stack_offset, stack_alloc;
|
||||
int argreg;
|
||||
int argnum;
|
||||
struct type *type;
|
||||
CORE_ADDR regval;
|
||||
char *val;
|
||||
char valbuf[4];
|
||||
int len;
|
||||
int odd_sized_struct;
|
||||
|
||||
/* first force sp to a 4-byte alignment */
|
||||
sp = sp & ~3;
|
||||
|
||||
argreg = ARG0_REGNUM;
|
||||
/* The "struct return pointer" pseudo-argument goes in R0 */
|
||||
if (struct_return)
|
||||
write_register (argreg++, struct_addr);
|
||||
|
||||
/* Now make sure there's space on the stack */
|
||||
for (argnum = 0, stack_alloc = 0;
|
||||
argnum < nargs; argnum++)
|
||||
stack_alloc += ((TYPE_LENGTH(VALUE_TYPE(args[argnum])) + 3) & ~3);
|
||||
sp -= stack_alloc; /* make room on stack for args */
|
||||
|
||||
|
||||
/* Now load as many as possible of the first arguments into
|
||||
registers, and push the rest onto the stack. There are 16 bytes
|
||||
in four registers available. Loop thru args from first to last. */
|
||||
|
||||
argreg = ARG0_REGNUM;
|
||||
for (argnum = 0, stack_offset = 0; argnum < nargs; argnum++)
|
||||
{
|
||||
type = VALUE_TYPE (args[argnum]);
|
||||
len = TYPE_LENGTH (type);
|
||||
memset(valbuf, 0, sizeof(valbuf));
|
||||
val = (char *) VALUE_CONTENTS (args[argnum]);
|
||||
if (len < 4)
|
||||
{ /* value gets right-justified in the register or stack word */
|
||||
memcpy(valbuf + (4 - len), val, len);
|
||||
val = valbuf;
|
||||
}
|
||||
|
||||
/* FIXME -- tic80 can take doubleword arguments in register pairs */
|
||||
if (len > 4 && (len & 3) != 0)
|
||||
odd_sized_struct = 1; /* such structs go entirely on stack */
|
||||
else
|
||||
odd_sized_struct = 0;
|
||||
while (len > 0)
|
||||
{
|
||||
if (argreg > ARGLAST_REGNUM || odd_sized_struct)
|
||||
{ /* must go on the stack */
|
||||
write_memory (sp + stack_offset, val, 4);
|
||||
stack_offset += 4;
|
||||
}
|
||||
/* NOTE WELL!!!!! This is not an "else if" clause!!!
|
||||
That's because some *&^%$ things get passed on the stack
|
||||
AND in the registers! */
|
||||
if (argreg <= ARGLAST_REGNUM)
|
||||
{ /* there's room in a register */
|
||||
regval = extract_address (val, REGISTER_RAW_SIZE(argreg));
|
||||
write_register (argreg, regval);
|
||||
argreg += 2; /* FIXME -- what about doubleword args? */
|
||||
}
|
||||
/* Store the value 4 bytes at a time. This means that things
|
||||
larger than 4 bytes may go partly in registers and partly
|
||||
on the stack. */
|
||||
len -= REGISTER_RAW_SIZE(argreg);
|
||||
val += REGISTER_RAW_SIZE(argreg);
|
||||
}
|
||||
}
|
||||
return sp;
|
||||
}
|
||||
|
||||
/* Function: get_saved_register
|
||||
Just call the generic_get_saved_register function. */
|
||||
|
||||
void
|
||||
get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval)
|
||||
char *raw_buffer;
|
||||
int *optimized;
|
||||
CORE_ADDR *addrp;
|
||||
struct frame_info *frame;
|
||||
int regnum;
|
||||
enum lval_type *lval;
|
||||
{
|
||||
generic_get_saved_register (raw_buffer, optimized, addrp,
|
||||
frame, regnum, lval);
|
||||
}
|
||||
|
||||
/* Function: tic80_write_sp
|
||||
Because SP is really a read-only register that mirrors either SPU or SPI,
|
||||
we must actually write one of those two as well, depending on PSW. */
|
||||
|
||||
void
|
||||
tic80_write_sp (val)
|
||||
CORE_ADDR val;
|
||||
{
|
||||
#if 0
|
||||
unsigned long psw = read_register (PSW_REGNUM);
|
||||
|
||||
if (psw & 0x80) /* stack mode: user or interrupt */
|
||||
write_register (SPU_REGNUM, val);
|
||||
else
|
||||
write_register (SPI_REGNUM, val);
|
||||
#endif
|
||||
write_register (SP_REGNUM, val);
|
||||
}
|
||||
|
||||
void
|
||||
_initialize_tic80_tdep ()
|
||||
{
|
||||
tm_print_insn = print_insn_tic80;
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in a new issue