1 /* Target-machine dependent code for Nios II, for GDB.
2 Copyright (C) 2012-2014 Free Software Foundation, Inc.
3 Contributed by Peter Brookes (pbrookes@altera.com)
4 and Andrew Draper (adraper@altera.com).
5 Contributed by Mentor Graphics, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "frame-unwind.h"
25 #include "frame-base.h"
26 #include "trad-frame.h"
27 #include "dwarf2-frame.h"
39 #include "arch-utils.h"
40 #include "floatformat.h"
43 #include "target-descriptions.h"
45 /* To get entry_point_address. */
48 /* Nios II ISA specific encodings and macros. */
49 #include "opcode/nios2.h"
51 /* Nios II specific header. */
52 #include "nios2-tdep.h"
54 #include "features/nios2.c"
56 /* Control debugging information emitted in this file. */
58 static int nios2_debug
= 0;
60 /* The following structures are used in the cache for prologue
61 analysis; see the reg_value and reg_saved tables in
62 struct nios2_unwind_cache, respectively. */
64 /* struct reg_value is used to record that a register has the same value
65 as reg at the given offset from the start of a function. */
73 /* struct reg_saved is used to record that a register value has been saved at
74 basereg + addr, for basereg >= 0. If basereg < 0, that indicates
75 that the register is not known to have been saved. Note that when
76 basereg == NIOS2_Z_REGNUM (that is, r0, which holds value 0),
77 addr is an absolute address. */
85 struct nios2_unwind_cache
87 /* The frame's base, optionally used by the high-level debug info. */
90 /* The previous frame's inner most stack address. Used as this
91 frame ID's stack_addr. */
94 /* The address of the first instruction in this function. */
97 /* Which register holds the return address for the frame. */
100 /* Table indicating what changes have been made to each register. */
101 struct reg_value reg_value
[NIOS2_NUM_REGS
];
103 /* Table indicating where each register has been saved. */
104 struct reg_saved reg_saved
[NIOS2_NUM_REGS
];
108 /* This array is a mapping from Dwarf-2 register numbering to GDB's. */
110 static int nios2_dwarf2gdb_regno_map
[] =
119 NIOS2_GP_REGNUM
, /* 26 */
120 NIOS2_SP_REGNUM
, /* 27 */
121 NIOS2_FP_REGNUM
, /* 28 */
122 NIOS2_EA_REGNUM
, /* 29 */
123 NIOS2_BA_REGNUM
, /* 30 */
124 NIOS2_RA_REGNUM
, /* 31 */
125 NIOS2_PC_REGNUM
, /* 32 */
126 NIOS2_STATUS_REGNUM
, /* 33 */
127 NIOS2_ESTATUS_REGNUM
, /* 34 */
128 NIOS2_BSTATUS_REGNUM
, /* 35 */
129 NIOS2_IENABLE_REGNUM
, /* 36 */
130 NIOS2_IPENDING_REGNUM
, /* 37 */
131 NIOS2_CPUID_REGNUM
, /* 38 */
132 39, /* CTL6 */ /* 39 */
133 NIOS2_EXCEPTION_REGNUM
, /* 40 */
134 NIOS2_PTEADDR_REGNUM
, /* 41 */
135 NIOS2_TLBACC_REGNUM
, /* 42 */
136 NIOS2_TLBMISC_REGNUM
, /* 43 */
137 NIOS2_ECCINJ_REGNUM
, /* 44 */
138 NIOS2_BADADDR_REGNUM
, /* 45 */
139 NIOS2_CONFIG_REGNUM
, /* 46 */
140 NIOS2_MPUBASE_REGNUM
, /* 47 */
141 NIOS2_MPUACC_REGNUM
/* 48 */
145 /* Implement the dwarf2_reg_to_regnum gdbarch method. */
148 nios2_dwarf_reg_to_regnum (struct gdbarch
*gdbarch
, int dw_reg
)
150 if (dw_reg
< 0 || dw_reg
> NIOS2_NUM_REGS
)
152 warning (_("Dwarf-2 uses unmapped register #%d"), dw_reg
);
156 return nios2_dwarf2gdb_regno_map
[dw_reg
];
159 /* Canonical names for the 49 registers. */
161 static const char *const nios2_reg_names
[NIOS2_NUM_REGS
] =
163 "zero", "at", "r2", "r3", "r4", "r5", "r6", "r7",
164 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
165 "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
166 "et", "bt", "gp", "sp", "fp", "ea", "sstatus", "ra",
168 "status", "estatus", "bstatus", "ienable",
169 "ipending", "cpuid", "ctl6", "exception",
170 "pteaddr", "tlbacc", "tlbmisc", "eccinj",
171 "badaddr", "config", "mpubase", "mpuacc"
174 /* Implement the register_name gdbarch method. */
177 nios2_register_name (struct gdbarch
*gdbarch
, int regno
)
179 /* Use mnemonic aliases for GPRs. */
180 if (regno
>= 0 && regno
< NIOS2_NUM_REGS
)
181 return nios2_reg_names
[regno
];
183 return tdesc_register_name (gdbarch
, regno
);
186 /* Implement the register_type gdbarch method. */
189 nios2_register_type (struct gdbarch
*gdbarch
, int regno
)
191 /* If the XML description has register information, use that to
192 determine the register type. */
193 if (tdesc_has_registers (gdbarch_target_desc (gdbarch
)))
194 return tdesc_register_type (gdbarch
, regno
);
196 if (regno
== NIOS2_PC_REGNUM
)
197 return builtin_type (gdbarch
)->builtin_func_ptr
;
198 else if (regno
== NIOS2_SP_REGNUM
)
199 return builtin_type (gdbarch
)->builtin_data_ptr
;
201 return builtin_type (gdbarch
)->builtin_uint32
;
204 /* Given a return value in REGCACHE with a type VALTYPE,
205 extract and copy its value into VALBUF. */
208 nios2_extract_return_value (struct gdbarch
*gdbarch
, struct type
*valtype
,
209 struct regcache
*regcache
, gdb_byte
*valbuf
)
211 int len
= TYPE_LENGTH (valtype
);
213 /* Return values of up to 8 bytes are returned in $r2 $r3. */
214 if (len
<= register_size (gdbarch
, NIOS2_R2_REGNUM
))
215 regcache_cooked_read (regcache
, NIOS2_R2_REGNUM
, valbuf
);
218 gdb_assert (len
<= (register_size (gdbarch
, NIOS2_R2_REGNUM
)
219 + register_size (gdbarch
, NIOS2_R3_REGNUM
)));
220 regcache_cooked_read (regcache
, NIOS2_R2_REGNUM
, valbuf
);
221 regcache_cooked_read (regcache
, NIOS2_R3_REGNUM
, valbuf
+ 4);
225 /* Write into appropriate registers a function return value
226 of type TYPE, given in virtual format. */
229 nios2_store_return_value (struct gdbarch
*gdbarch
, struct type
*valtype
,
230 struct regcache
*regcache
, const gdb_byte
*valbuf
)
232 int len
= TYPE_LENGTH (valtype
);
234 /* Return values of up to 8 bytes are returned in $r2 $r3. */
235 if (len
<= register_size (gdbarch
, NIOS2_R2_REGNUM
))
236 regcache_cooked_write (regcache
, NIOS2_R2_REGNUM
, valbuf
);
239 gdb_assert (len
<= (register_size (gdbarch
, NIOS2_R2_REGNUM
)
240 + register_size (gdbarch
, NIOS2_R3_REGNUM
)));
241 regcache_cooked_write (regcache
, NIOS2_R2_REGNUM
, valbuf
);
242 regcache_cooked_write (regcache
, NIOS2_R3_REGNUM
, valbuf
+ 4);
247 /* Set up the default values of the registers. */
250 nios2_setup_default (struct nios2_unwind_cache
*cache
)
254 for (i
= 0; i
< NIOS2_NUM_REGS
; i
++)
256 /* All registers start off holding their previous values. */
257 cache
->reg_value
[i
].reg
= i
;
258 cache
->reg_value
[i
].offset
= 0;
260 /* All registers start off not saved. */
261 cache
->reg_saved
[i
].basereg
= -1;
262 cache
->reg_saved
[i
].addr
= 0;
266 /* Initialize the unwind cache. */
269 nios2_init_cache (struct nios2_unwind_cache
*cache
, CORE_ADDR pc
)
274 cache
->return_regnum
= NIOS2_RA_REGNUM
;
275 nios2_setup_default (cache
);
278 /* Helper function to identify when we're in a function epilogue;
279 that is, the part of the function from the point at which the
280 stack adjustment is made, to the return or sibcall. On Nios II,
281 we want to check that the CURRENT_PC is a return-type instruction
282 and that the previous instruction is a stack adjustment.
283 START_PC is the beginning of the function in question. */
286 nios2_in_epilogue_p (struct gdbarch
*gdbarch
,
287 CORE_ADDR current_pc
,
290 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
292 /* There has to be a previous instruction in the function. */
293 if (current_pc
> start_pc
)
296 /* Check whether the previous instruction was a stack
299 = read_memory_unsigned_integer (current_pc
- NIOS2_OPCODE_SIZE
,
300 NIOS2_OPCODE_SIZE
, byte_order
);
302 if ((insn
& 0xffc0003c) == 0xdec00004 /* ADDI sp, sp, */
303 || (insn
& 0xffc1ffff) == 0xdec1883a /* ADD sp, sp, */
304 || (insn
& 0xffc0003f) == 0xdec00017) /* LDW sp, constant(sp) */
306 /* Then check if it's followed by a return or a tail
308 insn
= read_memory_unsigned_integer (current_pc
, NIOS2_OPCODE_SIZE
,
311 if (insn
== 0xf800283a /* RET */
312 || insn
== 0xe800083a /* ERET */
313 || (insn
& 0x07ffffff) == 0x0000683a /* JMP */
314 || (insn
& 0xffc0003f) == 6) /* BR */
321 /* Implement the in_function_epilogue_p gdbarch method. */
324 nios2_in_function_epilogue_p (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
328 if (find_pc_partial_function (pc
, NULL
, &func_addr
, NULL
))
329 return nios2_in_epilogue_p (gdbarch
, pc
, func_addr
);
334 /* Define some instruction patterns supporting wildcard bits via a
343 static const wild_insn profiler_insn
[] =
345 { 0x0010e03a, 0x00000000 }, /* nextpc r8 */
346 { 0xf813883a, 0x00000000 }, /* mov r9,ra */
347 { 0x02800034, 0x003fffc0 }, /* movhi r10,257 */
348 { 0x52800004, 0x003fffc0 }, /* addi r10,r10,-31992 */
349 { 0x00000000, 0xffffffc0 }, /* call <mcount> */
350 { 0x483f883a, 0x00000000 } /* mov ra,r9 */
353 static const wild_insn irqentry_insn
[] =
355 { 0x0031307a, 0x00000000 }, /* rdctl et,estatus */
356 { 0xc600004c, 0x00000000 }, /* andi et,et,1 */
357 { 0xc0000026, 0x003fffc0 }, /* beq et,zero, <software_exception> */
358 { 0x0031313a, 0x00000000 }, /* rdctl et,ipending */
359 { 0xc0000026, 0x003fffc0 } /* beq et,zero, <software_exception> */
363 /* Attempt to match SEQUENCE, which is COUNT insns long, at START_PC. */
366 nios2_match_sequence (struct gdbarch
*gdbarch
, CORE_ADDR start_pc
,
367 const wild_insn
*sequence
, int count
)
369 CORE_ADDR pc
= start_pc
;
372 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
374 for (i
= 0 ; i
< count
; i
++)
376 insn
= read_memory_unsigned_integer (pc
, NIOS2_OPCODE_SIZE
, byte_order
);
377 if ((insn
& ~sequence
[i
].mask
) != sequence
[i
].insn
)
380 pc
+= NIOS2_OPCODE_SIZE
;
386 /* Do prologue analysis, returning the PC of the first instruction
387 after the function prologue. Assumes CACHE has already been
388 initialized. THIS_FRAME can be null, in which case we are only
389 interested in skipping the prologue. Otherwise CACHE is filled in
390 from the frame information.
392 The prologue will consist of the following parts:
393 1) Optional profiling instrumentation. The old version uses six
394 instructions. We step over this if there is an exact match.
397 movhi r10, %hiadj(.LP2)
398 addi r10, r10, %lo(.LP2)
401 The new version uses two or three instructions (the last of
402 these might get merged in with the STW which saves RA to the
403 stack). We interpret these.
408 2) Optional interrupt entry decision. Again, we step over
409 this if there is an exact match.
412 beq et,zero, <software_exception>
414 beq et,zero, <software_exception>
416 3) A stack adjustment or stack which, which will be one of:
417 addi sp, sp, -constant
423 addi r8, r8, constant
426 movhi rx, %hiadj(newstack)
427 addhi rx, rx, %lo(newstack)
431 4) An optional stack check, which can take either of these forms:
435 bltu sp, rx, .Lstack_overflow
440 5) Saving any registers which need to be saved. These will
441 normally just be stored onto the stack:
443 but in the large frame case will use r8 as an offset back
446 stw rx, -constant(r8)
448 Saving control registers looks slightly different:
452 6) An optional FP setup, either if the user has requested a
453 frame pointer or if the function calls alloca.
457 The prologue instructions may be interleaved, and the register
458 saves and FP setup can occur in either order.
460 To cope with all this variability we decode all the instructions
461 from the start of the prologue until we hit a branch, call or
462 return. For each of the instructions mentioned in 3, 4 and 5 we
463 handle the limited cases of stores to the stack and operations
464 on constant values. */
467 nios2_analyze_prologue (struct gdbarch
*gdbarch
, const CORE_ADDR start_pc
,
468 const CORE_ADDR current_pc
,
469 struct nios2_unwind_cache
*cache
,
470 struct frame_info
*this_frame
)
472 /* Maximum lines of prologue to check.
473 Note that this number should not be too large, else we can
474 potentially end up iterating through unmapped memory. */
475 CORE_ADDR limit_pc
= start_pc
+ 200;
477 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
479 /* Does the frame set up the FP register? */
482 struct reg_value
*value
= cache
->reg_value
;
483 struct reg_value temp_value
[NIOS2_NUM_REGS
];
487 /* Save the starting PC so we can correct the pc after running
488 through the prolog, using symbol info. */
489 CORE_ADDR pc
= start_pc
;
491 /* Is this an exception handler? */
492 int exception_handler
= 0;
494 /* What was the original value of SP (or fake original value for
495 functions which switch stacks? */
496 CORE_ADDR frame_high
;
498 /* Is this the end of the prologue? */
499 int within_prologue
= 1;
501 CORE_ADDR prologue_end
;
503 /* Is this the innermost function? */
504 int innermost
= (this_frame
? (frame_relative_level (this_frame
) == 0) : 1);
507 fprintf_unfiltered (gdb_stdlog
,
508 "{ nios2_analyze_prologue start=%s, current=%s ",
509 paddress (gdbarch
, start_pc
),
510 paddress (gdbarch
, current_pc
));
512 /* Set up the default values of the registers. */
513 nios2_setup_default (cache
);
515 /* If the first few instructions are the profile entry, then skip
516 over them. Newer versions of the compiler use more efficient
518 if (nios2_match_sequence (gdbarch
, pc
, profiler_insn
,
519 ARRAY_SIZE (profiler_insn
)))
520 pc
+= ARRAY_SIZE (profiler_insn
) * NIOS2_OPCODE_SIZE
;
522 /* If the first few instructions are an interrupt entry, then skip
524 if (nios2_match_sequence (gdbarch
, pc
, irqentry_insn
,
525 ARRAY_SIZE (irqentry_insn
)))
527 pc
+= ARRAY_SIZE (irqentry_insn
) * NIOS2_OPCODE_SIZE
;
528 exception_handler
= 1;
531 prologue_end
= start_pc
;
533 /* Find the prologue instructions. */
534 while (pc
< limit_pc
&& within_prologue
)
536 /* Present instruction. */
539 int prologue_insn
= 0;
541 if (pc
== current_pc
)
543 /* When we reach the current PC we must save the current
544 register state (for the backtrace) but keep analysing
545 because there might be more to find out (eg. is this an
546 exception handler). */
547 memcpy (temp_value
, value
, sizeof (temp_value
));
550 fprintf_unfiltered (gdb_stdlog
, "*");
553 insn
= read_memory_unsigned_integer (pc
, NIOS2_OPCODE_SIZE
, byte_order
);
554 pc
+= NIOS2_OPCODE_SIZE
;
557 fprintf_unfiltered (gdb_stdlog
, "[%08X]", insn
);
559 /* The following instructions can appear in the prologue. */
561 if ((insn
& MASK_R1_ADD
) == MATCH_R1_ADD
)
563 /* ADD rc, ra, rb (also used for MOV) */
565 int ra
= GET_IW_R_A (insn
);
566 int rb
= GET_IW_R_B (insn
);
567 int rc
= GET_IW_R_C (insn
);
569 if (rc
== NIOS2_SP_REGNUM
571 && value
[ra
].reg
== cache
->reg_saved
[NIOS2_SP_REGNUM
].basereg
)
573 /* If the previous value of SP is available somewhere
574 near the new stack pointer value then this is a
577 /* If any registers were saved on the stack before then
578 we can't backtrace into them now. */
579 for (i
= 0 ; i
< NIOS2_NUM_REGS
; i
++)
581 if (cache
->reg_saved
[i
].basereg
== NIOS2_SP_REGNUM
)
582 cache
->reg_saved
[i
].basereg
= -1;
583 if (value
[i
].reg
== NIOS2_SP_REGNUM
)
587 /* Create a fake "high water mark" 4 bytes above where SP
588 was stored and fake up the registers to be consistent
590 value
[NIOS2_SP_REGNUM
].reg
= NIOS2_SP_REGNUM
;
591 value
[NIOS2_SP_REGNUM
].offset
593 - cache
->reg_saved
[NIOS2_SP_REGNUM
].addr
595 cache
->reg_saved
[NIOS2_SP_REGNUM
].basereg
= NIOS2_SP_REGNUM
;
596 cache
->reg_saved
[NIOS2_SP_REGNUM
].addr
= -4;
601 if (value
[rb
].reg
== 0)
602 value
[rc
].reg
= value
[ra
].reg
;
603 else if (value
[ra
].reg
== 0)
604 value
[rc
].reg
= value
[rb
].reg
;
607 value
[rc
].offset
= value
[ra
].offset
+ value
[rb
].offset
;
612 else if ((insn
& MASK_R1_SUB
) == MATCH_R1_SUB
)
616 int ra
= GET_IW_R_A (insn
);
617 int rb
= GET_IW_R_B (insn
);
618 int rc
= GET_IW_R_C (insn
);
622 if (value
[rb
].reg
== 0)
623 value
[rc
].reg
= value
[ra
].reg
;
626 value
[rc
].offset
= value
[ra
].offset
- value
[rb
].offset
;
630 else if ((insn
& MASK_R1_ADDI
) == MATCH_R1_ADDI
)
632 /* ADDI rb, ra, immed (also used for MOVI) */
633 short immed
= GET_IW_I_IMM16 (insn
);
634 int ra
= GET_IW_I_A (insn
);
635 int rb
= GET_IW_I_B (insn
);
637 /* The first stack adjustment is part of the prologue.
638 Any subsequent stack adjustments are either down to
639 alloca or the epilogue so stop analysing when we hit
641 if (rb
== NIOS2_SP_REGNUM
642 && (value
[rb
].offset
!= 0 || value
[ra
].reg
!= NIOS2_SP_REGNUM
))
647 value
[rb
].reg
= value
[ra
].reg
;
648 value
[rb
].offset
= value
[ra
].offset
+ immed
;
654 else if ((insn
& MASK_R1_ORHI
) == MATCH_R1_ORHI
)
656 /* ORHI rb, ra, immed (also used for MOVHI) */
657 unsigned int immed
= GET_IW_I_IMM16 (insn
);
658 int ra
= GET_IW_I_A (insn
);
659 int rb
= GET_IW_I_B (insn
);
663 value
[rb
].reg
= (value
[ra
].reg
== 0) ? 0 : -1;
664 value
[rb
].offset
= value
[ra
].offset
| (immed
<< 16);
668 else if ((insn
& MASK_R1_STW
) == MATCH_R1_STW
669 || (insn
& MASK_R1_STWIO
) == MATCH_R1_STWIO
)
671 /* STW rb, immediate(ra) */
673 short immed16
= GET_IW_I_IMM16 (insn
);
674 int ra
= GET_IW_I_A (insn
);
675 int rb
= GET_IW_I_B (insn
);
677 /* Are we storing the original value of a register?
678 For exception handlers the value of EA-4 (return
679 address from interrupts etc) is sometimes stored. */
680 int orig
= value
[rb
].reg
;
682 && (value
[rb
].offset
== 0
683 || (orig
== NIOS2_EA_REGNUM
&& value
[rb
].offset
== -4)))
685 /* We are most interested in stores to the stack, but
686 also take note of stores to other places as they
687 might be useful later. */
688 if ((value
[ra
].reg
== NIOS2_SP_REGNUM
689 && cache
->reg_saved
[orig
].basereg
!= NIOS2_SP_REGNUM
)
690 || cache
->reg_saved
[orig
].basereg
== -1)
694 /* Save off callee saved registers. */
695 cache
->reg_saved
[orig
].basereg
= value
[ra
].reg
;
696 cache
->reg_saved
[orig
].addr
= value
[ra
].offset
+ immed16
;
701 if (orig
== NIOS2_EA_REGNUM
|| orig
== NIOS2_ESTATUS_REGNUM
)
702 exception_handler
= 1;
706 /* Non-stack memory writes are not part of the
711 else if ((insn
& MASK_R1_RDCTL
) == MATCH_R1_RDCTL
)
714 int rc
= GET_IW_R_C (insn
);
715 int n
= GET_IW_R_A (insn
);
719 value
[rc
].reg
= NIOS2_STATUS_REGNUM
+ n
;
720 value
[rc
].offset
= 0;
726 else if ((insn
& MASK_R1_CALL
) == MATCH_R1_CALL
727 && value
[8].reg
== NIOS2_RA_REGNUM
728 && value
[8].offset
== 0
729 && value
[NIOS2_SP_REGNUM
].reg
== NIOS2_SP_REGNUM
730 && value
[NIOS2_SP_REGNUM
].offset
== 0)
732 /* A CALL instruction. This is treated as a call to mcount
733 if ra has been stored into r8 beforehand and if it's
734 before the stack adjust.
735 Note mcount corrupts r2-r3, r9-r15 & ra. */
736 for (i
= 2 ; i
<= 3 ; i
++)
738 for (i
= 9 ; i
<= 15 ; i
++)
740 value
[NIOS2_RA_REGNUM
].reg
= -1;
745 else if ((insn
& 0xf83fffff) == 0xd800012e)
749 This instruction sequence is used in stack checking;
751 unsigned int next_insn
752 = read_memory_unsigned_integer (pc
, NIOS2_OPCODE_SIZE
, byte_order
);
754 if (next_insn
!= 0x003da0fa)
757 pc
+= NIOS2_OPCODE_SIZE
;
760 else if ((insn
& 0xf800003f) == 0xd8000036)
762 /* BLTU sp, rx, .Lstackoverflow
763 If the location branched to holds a BREAK 3 instruction
764 then this is also stack overflow detection. We can
766 CORE_ADDR target_pc
= pc
+ ((insn
& 0x3fffc0) >> 6);
767 unsigned int target_insn
768 = read_memory_unsigned_integer (target_pc
, NIOS2_OPCODE_SIZE
,
771 if (target_insn
!= 0x003da0fa)
775 /* Any other instructions are allowed to be moved up into the
776 prologue. If we reach a branch, call or return then the
777 prologue is considered over. We also consider a second stack
778 adjustment as terminating the prologue (see above). */
781 switch (GET_IW_R1_OP (insn
))
794 if (GET_IW_R_OPX (insn
) == R1_OPX_RET
795 || GET_IW_R_OPX (insn
) == R1_OPX_ERET
796 || GET_IW_R_OPX (insn
) == R1_OPX_BRET
797 || GET_IW_R_OPX (insn
) == R1_OPX_CALLR
798 || GET_IW_R_OPX (insn
) == R1_OPX_JMP
)
810 /* If THIS_FRAME is NULL, we are being called from skip_prologue
811 and are only interested in the PROLOGUE_END value, so just
812 return that now and skip over the cache updates, which depend
813 on having frame information. */
814 if (this_frame
== NULL
)
817 /* If we are in the function epilogue and have already popped
818 registers off the stack in preparation for returning, then we
819 want to go back to the original register values. */
820 if (innermost
&& nios2_in_epilogue_p (gdbarch
, current_pc
, start_pc
))
821 nios2_setup_default (cache
);
823 /* Exception handlers use a different return address register. */
824 if (exception_handler
)
825 cache
->return_regnum
= NIOS2_EA_REGNUM
;
828 fprintf_unfiltered (gdb_stdlog
, "\n-> retreg=%d, ", cache
->return_regnum
);
830 if (cache
->reg_value
[NIOS2_FP_REGNUM
].reg
== NIOS2_SP_REGNUM
)
831 /* If the FP now holds an offset from the CFA then this is a
832 normal frame which uses the frame pointer. */
833 base_reg
= NIOS2_FP_REGNUM
;
834 else if (cache
->reg_value
[NIOS2_SP_REGNUM
].reg
== NIOS2_SP_REGNUM
)
835 /* FP doesn't hold an offset from the CFA. If SP still holds an
836 offset from the CFA then we might be in a function which omits
837 the frame pointer, or we might be partway through the prologue.
838 In both cases we can find the CFA using SP. */
839 base_reg
= NIOS2_SP_REGNUM
;
842 /* Somehow the stack pointer has been corrupted.
845 fprintf_unfiltered (gdb_stdlog
, "<can't reach cfa> }\n");
849 if (cache
->reg_value
[base_reg
].offset
== 0
850 || cache
->reg_saved
[NIOS2_RA_REGNUM
].basereg
!= NIOS2_SP_REGNUM
851 || cache
->reg_saved
[cache
->return_regnum
].basereg
!= NIOS2_SP_REGNUM
)
853 /* If the frame didn't adjust the stack, didn't save RA or
854 didn't save EA in an exception handler then it must either
855 be a leaf function (doesn't call any other functions) or it
856 can't return. If it has called another function then it
857 can't be a leaf, so set base == 0 to indicate that we can't
858 backtrace past it. */
862 /* If it isn't the innermost function then it can't be a
863 leaf, unless it was interrupted. Check whether RA for
864 this frame is the same as PC. If so then it probably
865 wasn't interrupted. */
867 = get_frame_register_unsigned (this_frame
, NIOS2_RA_REGNUM
);
869 if (ra
== current_pc
)
874 "<noreturn ADJUST %s, r31@r%d+?>, r%d@r%d+?> }\n",
875 paddress (gdbarch
, cache
->reg_value
[base_reg
].offset
),
876 cache
->reg_saved
[NIOS2_RA_REGNUM
].basereg
,
877 cache
->return_regnum
,
878 cache
->reg_saved
[cache
->return_regnum
].basereg
);
884 /* Get the value of whichever register we are using for the
886 cache
->base
= get_frame_register_unsigned (this_frame
, base_reg
);
888 /* What was the value of SP at the start of this function (or just
889 after the stack switch). */
890 frame_high
= cache
->base
- cache
->reg_value
[base_reg
].offset
;
892 /* Adjust all the saved registers such that they contain addresses
893 instead of offsets. */
894 for (i
= 0; i
< NIOS2_NUM_REGS
; i
++)
895 if (cache
->reg_saved
[i
].basereg
== NIOS2_SP_REGNUM
)
897 cache
->reg_saved
[i
].basereg
= NIOS2_Z_REGNUM
;
898 cache
->reg_saved
[i
].addr
+= frame_high
;
901 for (i
= 0; i
< NIOS2_NUM_REGS
; i
++)
902 if (cache
->reg_saved
[i
].basereg
== NIOS2_GP_REGNUM
)
904 CORE_ADDR gp
= get_frame_register_unsigned (this_frame
,
907 for ( ; i
< NIOS2_NUM_REGS
; i
++)
908 if (cache
->reg_saved
[i
].basereg
== NIOS2_GP_REGNUM
)
910 cache
->reg_saved
[i
].basereg
= NIOS2_Z_REGNUM
;
911 cache
->reg_saved
[i
].addr
+= gp
;
915 /* Work out what the value of SP was on the first instruction of
916 this function. If we didn't switch stacks then this can be
917 trivially computed from the base address. */
918 if (cache
->reg_saved
[NIOS2_SP_REGNUM
].basereg
== NIOS2_Z_REGNUM
)
920 = read_memory_unsigned_integer (cache
->reg_saved
[NIOS2_SP_REGNUM
].addr
,
923 cache
->cfa
= frame_high
;
925 /* Exception handlers restore ESTATUS into STATUS. */
926 if (exception_handler
)
928 cache
->reg_saved
[NIOS2_STATUS_REGNUM
]
929 = cache
->reg_saved
[NIOS2_ESTATUS_REGNUM
];
930 cache
->reg_saved
[NIOS2_ESTATUS_REGNUM
].basereg
= -1;
934 fprintf_unfiltered (gdb_stdlog
, "cfa=%s }\n",
935 paddress (gdbarch
, cache
->cfa
));
940 /* Implement the skip_prologue gdbarch hook. */
943 nios2_skip_prologue (struct gdbarch
*gdbarch
, CORE_ADDR start_pc
)
948 struct nios2_unwind_cache cache
;
950 /* See if we can determine the end of the prologue via the symbol
951 table. If so, then return either PC, or the PC after the
952 prologue, whichever is greater. */
953 if (find_pc_partial_function (start_pc
, NULL
, &func_addr
, NULL
))
955 CORE_ADDR post_prologue_pc
956 = skip_prologue_using_sal (gdbarch
, func_addr
);
958 if (post_prologue_pc
!= 0)
959 return max (start_pc
, post_prologue_pc
);
962 /* Prologue analysis does the rest.... */
963 nios2_init_cache (&cache
, start_pc
);
964 return nios2_analyze_prologue (gdbarch
, start_pc
, start_pc
, &cache
, NULL
);
967 /* Implement the breakpoint_from_pc gdbarch hook. */
969 static const gdb_byte
*
970 nios2_breakpoint_from_pc (struct gdbarch
*gdbarch
, CORE_ADDR
*bp_addr
,
973 /* break encoding: 31->27 26->22 21->17 16->11 10->6 5->0 */
974 /* 00000 00000 0x1d 0x2d 11111 0x3a */
975 /* 00000 00000 11101 101101 11111 111010 */
976 /* In bytes: 00000000 00111011 01101111 11111010 */
977 /* 0x0 0x3b 0x6f 0xfa */
978 static const gdb_byte breakpoint_le
[] = {0xfa, 0x6f, 0x3b, 0x0};
979 static const gdb_byte breakpoint_be
[] = {0x0, 0x3b, 0x6f, 0xfa};
981 enum bfd_endian byte_order_for_code
= gdbarch_byte_order_for_code (gdbarch
);
984 if (gdbarch_byte_order_for_code (gdbarch
) == BFD_ENDIAN_BIG
)
985 return breakpoint_be
;
987 return breakpoint_le
;
990 /* Implement the print_insn gdbarch method. */
993 nios2_print_insn (bfd_vma memaddr
, disassemble_info
*info
)
995 if (info
->endian
== BFD_ENDIAN_BIG
)
996 return print_insn_big_nios2 (memaddr
, info
);
998 return print_insn_little_nios2 (memaddr
, info
);
1002 /* Implement the frame_align gdbarch method. */
1005 nios2_frame_align (struct gdbarch
*gdbarch
, CORE_ADDR addr
)
1007 return align_down (addr
, 4);
1011 /* Implement the return_value gdbarch method. */
1013 static enum return_value_convention
1014 nios2_return_value (struct gdbarch
*gdbarch
, struct value
*function
,
1015 struct type
*type
, struct regcache
*regcache
,
1016 gdb_byte
*readbuf
, const gdb_byte
*writebuf
)
1018 if (TYPE_LENGTH (type
) > 8)
1019 return RETURN_VALUE_STRUCT_CONVENTION
;
1022 nios2_extract_return_value (gdbarch
, type
, regcache
, readbuf
);
1024 nios2_store_return_value (gdbarch
, type
, regcache
, writebuf
);
1026 return RETURN_VALUE_REGISTER_CONVENTION
;
1029 /* Implement the dummy_id gdbarch method. */
1031 static struct frame_id
1032 nios2_dummy_id (struct gdbarch
*gdbarch
, struct frame_info
*this_frame
)
1034 return frame_id_build
1035 (get_frame_register_unsigned (this_frame
, NIOS2_SP_REGNUM
),
1036 get_frame_pc (this_frame
));
1039 /* Implement the push_dummy_call gdbarch method. */
1042 nios2_push_dummy_call (struct gdbarch
*gdbarch
, struct value
*function
,
1043 struct regcache
*regcache
, CORE_ADDR bp_addr
,
1044 int nargs
, struct value
**args
, CORE_ADDR sp
,
1045 int struct_return
, CORE_ADDR struct_addr
)
1051 int stack_offset
= 0;
1052 CORE_ADDR func_addr
= find_function_addr (function
, NULL
);
1053 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
1055 /* Set the return address register to point to the entry point of
1056 the program, where a breakpoint lies in wait. */
1057 regcache_cooked_write_signed (regcache
, NIOS2_RA_REGNUM
, bp_addr
);
1059 /* Now make space on the stack for the args. */
1060 for (argnum
= 0; argnum
< nargs
; argnum
++)
1061 len
+= align_up (TYPE_LENGTH (value_type (args
[argnum
])), 4);
1064 /* Initialize the register pointer. */
1065 argreg
= NIOS2_FIRST_ARGREG
;
1067 /* The struct_return pointer occupies the first parameter-passing
1070 regcache_cooked_write_unsigned (regcache
, argreg
++, struct_addr
);
1072 /* Now load as many as possible of the first arguments into
1073 registers, and push the rest onto the stack. Loop through args
1074 from first to last. */
1075 for (argnum
= 0; argnum
< nargs
; argnum
++)
1077 const gdb_byte
*val
;
1078 gdb_byte valbuf
[MAX_REGISTER_SIZE
];
1079 struct value
*arg
= args
[argnum
];
1080 struct type
*arg_type
= check_typedef (value_type (arg
));
1081 int len
= TYPE_LENGTH (arg_type
);
1082 enum type_code typecode
= TYPE_CODE (arg_type
);
1084 val
= value_contents (arg
);
1086 /* Copy the argument to general registers or the stack in
1087 register-sized pieces. Large arguments are split between
1088 registers and stack. */
1091 int partial_len
= (len
< 4 ? len
: 4);
1093 if (argreg
<= NIOS2_LAST_ARGREG
)
1095 /* The argument is being passed in a register. */
1096 CORE_ADDR regval
= extract_unsigned_integer (val
, partial_len
,
1099 regcache_cooked_write_unsigned (regcache
, argreg
, regval
);
1104 /* The argument is being passed on the stack. */
1105 CORE_ADDR addr
= sp
+ stack_offset
;
1107 write_memory (addr
, val
, partial_len
);
1108 stack_offset
+= align_up (partial_len
, 4);
1116 regcache_cooked_write_signed (regcache
, NIOS2_SP_REGNUM
, sp
);
1118 /* Return adjusted stack pointer. */
1122 /* Implement the unwind_pc gdbarch method. */
1125 nios2_unwind_pc (struct gdbarch
*gdbarch
, struct frame_info
*next_frame
)
1129 frame_unwind_register (next_frame
, NIOS2_PC_REGNUM
, buf
);
1130 return extract_typed_address (buf
, builtin_type (gdbarch
)->builtin_func_ptr
);
1133 /* Implement the unwind_sp gdbarch method. */
1136 nios2_unwind_sp (struct gdbarch
*gdbarch
, struct frame_info
*this_frame
)
1138 return frame_unwind_register_unsigned (this_frame
, NIOS2_SP_REGNUM
);
1141 /* Use prologue analysis to fill in the register cache
1142 *THIS_PROLOGUE_CACHE for THIS_FRAME. This function initializes
1143 *THIS_PROLOGUE_CACHE first. */
1145 static struct nios2_unwind_cache
*
1146 nios2_frame_unwind_cache (struct frame_info
*this_frame
,
1147 void **this_prologue_cache
)
1149 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
1150 CORE_ADDR current_pc
;
1151 struct nios2_unwind_cache
*cache
;
1154 if (*this_prologue_cache
)
1155 return *this_prologue_cache
;
1157 cache
= FRAME_OBSTACK_ZALLOC (struct nios2_unwind_cache
);
1158 *this_prologue_cache
= cache
;
1160 /* Zero all fields. */
1161 nios2_init_cache (cache
, get_frame_func (this_frame
));
1163 /* Prologue analysis does the rest... */
1164 current_pc
= get_frame_pc (this_frame
);
1166 nios2_analyze_prologue (gdbarch
, cache
->pc
, current_pc
, cache
, this_frame
);
1171 /* Implement the this_id function for the normal unwinder. */
1174 nios2_frame_this_id (struct frame_info
*this_frame
, void **this_cache
,
1175 struct frame_id
*this_id
)
1177 struct nios2_unwind_cache
*cache
=
1178 nios2_frame_unwind_cache (this_frame
, this_cache
);
1180 /* This marks the outermost frame. */
1181 if (cache
->base
== 0)
1184 *this_id
= frame_id_build (cache
->cfa
, cache
->pc
);
1187 /* Implement the prev_register function for the normal unwinder. */
1189 static struct value
*
1190 nios2_frame_prev_register (struct frame_info
*this_frame
, void **this_cache
,
1193 struct nios2_unwind_cache
*cache
=
1194 nios2_frame_unwind_cache (this_frame
, this_cache
);
1196 gdb_assert (regnum
>= 0 && regnum
< NIOS2_NUM_REGS
);
1198 /* The PC of the previous frame is stored in the RA register of
1199 the current frame. Frob regnum so that we pull the value from
1200 the correct place. */
1201 if (regnum
== NIOS2_PC_REGNUM
)
1202 regnum
= cache
->return_regnum
;
1204 if (regnum
== NIOS2_SP_REGNUM
&& cache
->cfa
)
1205 return frame_unwind_got_constant (this_frame
, regnum
, cache
->cfa
);
1207 /* If we've worked out where a register is stored then load it from
1209 if (cache
->reg_saved
[regnum
].basereg
== NIOS2_Z_REGNUM
)
1210 return frame_unwind_got_memory (this_frame
, regnum
,
1211 cache
->reg_saved
[regnum
].addr
);
1213 return frame_unwind_got_register (this_frame
, regnum
, regnum
);
1216 /* Implement the this_base, this_locals, and this_args hooks
1217 for the normal unwinder. */
1220 nios2_frame_base_address (struct frame_info
*this_frame
, void **this_cache
)
1222 struct nios2_unwind_cache
*info
1223 = nios2_frame_unwind_cache (this_frame
, this_cache
);
1228 /* Data structures for the normal prologue-analysis-based
1231 static const struct frame_unwind nios2_frame_unwind
=
1234 default_frame_unwind_stop_reason
,
1235 nios2_frame_this_id
,
1236 nios2_frame_prev_register
,
1238 default_frame_sniffer
1241 static const struct frame_base nios2_frame_base
=
1243 &nios2_frame_unwind
,
1244 nios2_frame_base_address
,
1245 nios2_frame_base_address
,
1246 nios2_frame_base_address
1249 /* Fill in the register cache *THIS_CACHE for THIS_FRAME for use
1250 in the stub unwinder. */
1252 static struct trad_frame_cache
*
1253 nios2_stub_frame_cache (struct frame_info
*this_frame
, void **this_cache
)
1256 CORE_ADDR start_addr
;
1257 CORE_ADDR stack_addr
;
1258 struct trad_frame_cache
*this_trad_cache
;
1259 struct gdbarch
*gdbarch
= get_frame_arch (this_frame
);
1260 int num_regs
= gdbarch_num_regs (gdbarch
);
1262 if (*this_cache
!= NULL
)
1264 this_trad_cache
= trad_frame_cache_zalloc (this_frame
);
1265 *this_cache
= this_trad_cache
;
1267 /* The return address is in the link register. */
1268 trad_frame_set_reg_realreg (this_trad_cache
,
1269 gdbarch_pc_regnum (gdbarch
),
1272 /* Frame ID, since it's a frameless / stackless function, no stack
1273 space is allocated and SP on entry is the current SP. */
1274 pc
= get_frame_pc (this_frame
);
1275 find_pc_partial_function (pc
, NULL
, &start_addr
, NULL
);
1276 stack_addr
= get_frame_register_unsigned (this_frame
, NIOS2_SP_REGNUM
);
1277 trad_frame_set_id (this_trad_cache
, frame_id_build (start_addr
, stack_addr
));
1278 /* Assume that the frame's base is the same as the stack pointer. */
1279 trad_frame_set_this_base (this_trad_cache
, stack_addr
);
1281 return this_trad_cache
;
1284 /* Implement the this_id function for the stub unwinder. */
1287 nios2_stub_frame_this_id (struct frame_info
*this_frame
, void **this_cache
,
1288 struct frame_id
*this_id
)
1290 struct trad_frame_cache
*this_trad_cache
1291 = nios2_stub_frame_cache (this_frame
, this_cache
);
1293 trad_frame_get_id (this_trad_cache
, this_id
);
1296 /* Implement the prev_register function for the stub unwinder. */
1298 static struct value
*
1299 nios2_stub_frame_prev_register (struct frame_info
*this_frame
,
1300 void **this_cache
, int regnum
)
1302 struct trad_frame_cache
*this_trad_cache
1303 = nios2_stub_frame_cache (this_frame
, this_cache
);
1305 return trad_frame_get_register (this_trad_cache
, this_frame
, regnum
);
1308 /* Implement the sniffer function for the stub unwinder.
1309 This unwinder is used for cases where the normal
1310 prologue-analysis-based unwinder can't work,
1311 such as PLT stubs. */
1314 nios2_stub_frame_sniffer (const struct frame_unwind
*self
,
1315 struct frame_info
*this_frame
, void **cache
)
1318 struct obj_section
*s
;
1319 CORE_ADDR pc
= get_frame_address_in_block (this_frame
);
1321 /* Use the stub unwinder for unreadable code. */
1322 if (target_read_memory (get_frame_pc (this_frame
), dummy
, 4) != 0)
1325 if (in_plt_section (pc
))
1331 /* Define the data structures for the stub unwinder. */
1333 static const struct frame_unwind nios2_stub_frame_unwind
=
1336 default_frame_unwind_stop_reason
,
1337 nios2_stub_frame_this_id
,
1338 nios2_stub_frame_prev_register
,
1340 nios2_stub_frame_sniffer
1343 /* Helper function to read an instruction at PC. */
1345 static unsigned long
1346 nios2_fetch_instruction (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
1348 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
1350 return read_memory_unsigned_integer (pc
, NIOS2_OPCODE_SIZE
, byte_order
);
1353 /* Determine where to set a single step breakpoint while considering
1354 branch prediction. */
1357 nios2_get_next_pc (struct frame_info
*frame
, CORE_ADDR pc
)
1359 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
1360 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
1371 inst
= nios2_fetch_instruction (gdbarch
, pc
);
1372 pc
+= NIOS2_OPCODE_SIZE
;
1374 imm16
= (short) GET_IW_I_IMM16 (inst
);
1375 ra
= GET_IW_I_A (inst
);
1376 rb
= GET_IW_I_B (inst
);
1377 ras
= get_frame_register_signed (frame
, ra
);
1378 rbs
= get_frame_register_signed (frame
, rb
);
1379 rau
= get_frame_register_unsigned (frame
, ra
);
1380 rbu
= get_frame_register_unsigned (frame
, rb
);
1382 switch (GET_IW_R1_OP (inst
))
1420 pc
= (pc
& 0xf0000000) | (GET_IW_J_IMM26 (inst
) << 2);
1424 switch (GET_IW_R_OPX (inst
))
1433 if (tdep
->syscall_next_pc
!= NULL
)
1434 return tdep
->syscall_next_pc (frame
);
1446 /* Implement the software_single_step gdbarch method. */
1449 nios2_software_single_step (struct frame_info
*frame
)
1451 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
1452 struct address_space
*aspace
= get_frame_address_space (frame
);
1453 CORE_ADDR next_pc
= nios2_get_next_pc (frame
, get_frame_pc (frame
));
1455 insert_single_step_breakpoint (gdbarch
, aspace
, next_pc
);
1460 /* Implement the get_longjump_target gdbarch method. */
1463 nios2_get_longjmp_target (struct frame_info
*frame
, CORE_ADDR
*pc
)
1465 struct gdbarch
*gdbarch
= get_frame_arch (frame
);
1466 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
1467 enum bfd_endian byte_order
= gdbarch_byte_order (gdbarch
);
1468 CORE_ADDR jb_addr
= get_frame_register_unsigned (frame
, NIOS2_R4_REGNUM
);
1471 if (target_read_memory (jb_addr
+ (tdep
->jb_pc
* 4), buf
, 4))
1474 *pc
= extract_unsigned_integer (buf
, 4, byte_order
);
1478 /* Initialize the Nios II gdbarch. */
1480 static struct gdbarch
*
1481 nios2_gdbarch_init (struct gdbarch_info info
, struct gdbarch_list
*arches
)
1483 struct gdbarch
*gdbarch
;
1484 struct gdbarch_tdep
*tdep
;
1485 int register_bytes
, i
;
1486 struct tdesc_arch_data
*tdesc_data
= NULL
;
1487 const struct target_desc
*tdesc
= info
.target_desc
;
1489 if (!tdesc_has_registers (tdesc
))
1490 /* Pick a default target description. */
1491 tdesc
= tdesc_nios2
;
1493 /* Check any target description for validity. */
1494 if (tdesc_has_registers (tdesc
))
1496 const struct tdesc_feature
*feature
;
1499 feature
= tdesc_find_feature (tdesc
, "org.gnu.gdb.nios2.cpu");
1500 if (feature
== NULL
)
1503 tdesc_data
= tdesc_data_alloc ();
1507 for (i
= 0; i
< NIOS2_NUM_REGS
; i
++)
1508 valid_p
&= tdesc_numbered_register (feature
, tdesc_data
, i
,
1509 nios2_reg_names
[i
]);
1513 tdesc_data_cleanup (tdesc_data
);
1518 /* Find a candidate among the list of pre-declared architectures. */
1519 arches
= gdbarch_list_lookup_by_info (arches
, &info
);
1521 return arches
->gdbarch
;
1523 /* None found, create a new architecture from the information
1525 tdep
= xcalloc (1, sizeof (struct gdbarch_tdep
));
1526 gdbarch
= gdbarch_alloc (&info
, tdep
);
1528 /* longjmp support not enabled by default. */
1531 /* Data type sizes. */
1532 set_gdbarch_ptr_bit (gdbarch
, 32);
1533 set_gdbarch_addr_bit (gdbarch
, 32);
1534 set_gdbarch_short_bit (gdbarch
, 16);
1535 set_gdbarch_int_bit (gdbarch
, 32);
1536 set_gdbarch_long_bit (gdbarch
, 32);
1537 set_gdbarch_long_long_bit (gdbarch
, 64);
1538 set_gdbarch_float_bit (gdbarch
, 32);
1539 set_gdbarch_double_bit (gdbarch
, 64);
1541 set_gdbarch_float_format (gdbarch
, floatformats_ieee_single
);
1542 set_gdbarch_double_format (gdbarch
, floatformats_ieee_double
);
1544 /* The register set. */
1545 set_gdbarch_num_regs (gdbarch
, NIOS2_NUM_REGS
);
1546 set_gdbarch_sp_regnum (gdbarch
, NIOS2_SP_REGNUM
);
1547 set_gdbarch_pc_regnum (gdbarch
, NIOS2_PC_REGNUM
); /* Pseudo register PC */
1549 set_gdbarch_register_name (gdbarch
, nios2_register_name
);
1550 set_gdbarch_register_type (gdbarch
, nios2_register_type
);
1552 /* Provide register mappings for stabs and dwarf2. */
1553 set_gdbarch_stab_reg_to_regnum (gdbarch
, nios2_dwarf_reg_to_regnum
);
1554 set_gdbarch_dwarf2_reg_to_regnum (gdbarch
, nios2_dwarf_reg_to_regnum
);
1556 set_gdbarch_inner_than (gdbarch
, core_addr_lessthan
);
1558 /* Call dummy code. */
1559 set_gdbarch_frame_align (gdbarch
, nios2_frame_align
);
1561 set_gdbarch_return_value (gdbarch
, nios2_return_value
);
1563 set_gdbarch_skip_prologue (gdbarch
, nios2_skip_prologue
);
1564 set_gdbarch_in_function_epilogue_p (gdbarch
, nios2_in_function_epilogue_p
);
1565 set_gdbarch_breakpoint_from_pc (gdbarch
, nios2_breakpoint_from_pc
);
1567 set_gdbarch_dummy_id (gdbarch
, nios2_dummy_id
);
1568 set_gdbarch_unwind_pc (gdbarch
, nios2_unwind_pc
);
1569 set_gdbarch_unwind_sp (gdbarch
, nios2_unwind_sp
);
1571 /* The dwarf2 unwinder will normally produce the best results if
1572 the debug information is available, so register it first. */
1573 dwarf2_append_unwinders (gdbarch
);
1574 frame_unwind_append_unwinder (gdbarch
, &nios2_stub_frame_unwind
);
1575 frame_unwind_append_unwinder (gdbarch
, &nios2_frame_unwind
);
1577 /* Single stepping. */
1578 set_gdbarch_software_single_step (gdbarch
, nios2_software_single_step
);
1580 /* Hook in ABI-specific overrides, if they have been registered. */
1581 gdbarch_init_osabi (info
, gdbarch
);
1583 if (tdep
->jb_pc
>= 0)
1584 set_gdbarch_get_longjmp_target (gdbarch
, nios2_get_longjmp_target
);
1586 frame_base_set_default (gdbarch
, &nios2_frame_base
);
1588 set_gdbarch_print_insn (gdbarch
, nios2_print_insn
);
1590 /* Enable inferior call support. */
1591 set_gdbarch_push_dummy_call (gdbarch
, nios2_push_dummy_call
);
1594 tdesc_use_registers (gdbarch
, tdesc
, tdesc_data
);
1599 extern initialize_file_ftype _initialize_nios2_tdep
; /* -Wmissing-prototypes */
1602 _initialize_nios2_tdep (void)
1604 gdbarch_register (bfd_arch_nios2
, nios2_gdbarch_init
, NULL
);
1605 initialize_tdesc_nios2 ();
1607 /* Allow debugging this file's internals. */
1608 add_setshow_boolean_cmd ("nios2", class_maintenance
, &nios2_debug
,
1609 _("Set Nios II debugging."),
1610 _("Show Nios II debugging."),
1611 _("When on, Nios II specific debugging is enabled."),
1614 &setdebuglist
, &showdebuglist
);