1 /* Target dependent code for GDB on TI C6x systems.
3 Copyright (C) 2010-2017 Free Software Foundation, Inc.
4 Contributed by Andrew Jenner <andrew@codesourcery.com>
5 Contributed by Yao Qi <yao@codesourcery.com>
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"
38 #include "arch-utils.h"
39 #include "floatformat.h"
40 #include "glibc-tdep.h"
43 #include "tramp-frame.h"
44 #include "linux-tdep.h"
48 #include "tic6x-tdep.h"
50 #include "target-descriptions.h"
53 #include "features/tic6x-c64xp.c"
54 #include "features/tic6x-c64x.c"
55 #include "features/tic6x-c62x.c"
57 #define TIC6X_OPCODE_SIZE 4
58 #define TIC6X_FETCH_PACKET_SIZE 32
60 #define INST_S_BIT(INST) ((INST >> 1) & 1)
61 #define INST_X_BIT(INST) ((INST >> 12) & 1)
63 const gdb_byte tic6x_bkpt_illegal_opcode_be[] = { 0x56, 0x45, 0x43, 0x14 };
64 const gdb_byte tic6x_bkpt_illegal_opcode_le[] = { 0x14, 0x43, 0x45, 0x56 };
66 struct tic6x_unwind_cache
68 /* The frame's base, optionally used by the high-level debug info. */
71 /* The previous frame's inner most stack address. Used as this
72 frame ID's stack_addr. */
75 /* The address of the first instruction in this function */
78 /* Which register holds the return address for the frame. */
81 /* The offset of register saved on stack. If register is not saved, the
82 corresponding element is -1. */
83 CORE_ADDR reg_saved[TIC6X_NUM_CORE_REGS];
87 /* Name of TI C6x core registers. */
88 static const char *const tic6x_register_names[] =
90 "A0", "A1", "A2", "A3", /* 0 1 2 3 */
91 "A4", "A5", "A6", "A7", /* 4 5 6 7 */
92 "A8", "A9", "A10", "A11", /* 8 9 10 11 */
93 "A12", "A13", "A14", "A15", /* 12 13 14 15 */
94 "B0", "B1", "B2", "B3", /* 16 17 18 19 */
95 "B4", "B5", "B6", "B7", /* 20 21 22 23 */
96 "B8", "B9", "B10", "B11", /* 24 25 26 27 */
97 "B12", "B13", "B14", "B15", /* 28 29 30 31 */
98 "CSR", "PC", /* 32 33 */
101 /* This array maps the arguments to the register number which passes argument
102 in function call according to C6000 ELF ABI. */
103 static const int arg_regs[] = { 4, 20, 6, 22, 8, 24, 10, 26, 12, 28 };
105 /* This is the implementation of gdbarch method register_name. */
108 tic6x_register_name (struct gdbarch *gdbarch, int regno)
113 if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
114 return tdesc_register_name (gdbarch, regno);
115 else if (regno >= ARRAY_SIZE (tic6x_register_names))
118 return tic6x_register_names[regno];
121 /* This is the implementation of gdbarch method register_type. */
124 tic6x_register_type (struct gdbarch *gdbarch, int regno)
127 if (regno == TIC6X_PC_REGNUM)
128 return builtin_type (gdbarch)->builtin_func_ptr;
130 return builtin_type (gdbarch)->builtin_uint32;
134 tic6x_setup_default (struct tic6x_unwind_cache *cache)
138 for (i = 0; i < TIC6X_NUM_CORE_REGS; i++)
139 cache->reg_saved[i] = -1;
142 static unsigned long tic6x_fetch_instruction (struct gdbarch *, CORE_ADDR);
143 static int tic6x_register_number (int reg, int side, int crosspath);
145 /* Do a full analysis of the prologue at START_PC and update CACHE accordingly.
146 Bail out early if CURRENT_PC is reached. Returns the address of the first
147 instruction after the prologue. */
150 tic6x_analyze_prologue (struct gdbarch *gdbarch, const CORE_ADDR start_pc,
151 const CORE_ADDR current_pc,
152 struct tic6x_unwind_cache *cache,
153 struct frame_info *this_frame)
156 unsigned int src_reg, base_reg, dst_reg;
158 CORE_ADDR pc = start_pc;
159 CORE_ADDR return_pc = start_pc;
160 int frame_base_offset_to_sp = 0;
161 /* Counter of non-stw instructions after first insn ` sub sp, xxx, sp'. */
162 int non_stw_insn_counter = 0;
164 if (start_pc >= current_pc)
165 return_pc = current_pc;
169 /* The landmarks in prologue is one or two SUB instructions to SP.
170 Instructions on setting up dsbt are in the last part of prologue, if
171 needed. In maxim, prologue can be divided to three parts by two
172 `sub sp, xx, sp' insns. */
174 /* Step 1: Look for the 1st and 2nd insn `sub sp, xx, sp', in which, the
175 2nd one is optional. */
176 while (pc < current_pc)
178 unsigned long inst = tic6x_fetch_instruction (gdbarch, pc);
180 if ((inst & 0x1ffc) == 0x1dc0 || (inst & 0x1ffc) == 0x1bc0
181 || (inst & 0x0ffc) == 0x9c0)
183 /* SUBAW/SUBAH/SUB, and src1 is ucst 5. */
184 unsigned int src2 = tic6x_register_number ((inst >> 18) & 0x1f,
185 INST_S_BIT (inst), 0);
186 unsigned int dst = tic6x_register_number ((inst >> 23) & 0x1f,
187 INST_S_BIT (inst), 0);
189 if (src2 == TIC6X_SP_REGNUM && dst == TIC6X_SP_REGNUM)
191 /* Extract const from insn SUBAW/SUBAH/SUB, and translate it to
192 offset. The constant offset is decoded in bit 13-17 in all
193 these three kinds of instructions. */
194 unsigned int ucst5 = (inst >> 13) & 0x1f;
196 if ((inst & 0x1ffc) == 0x1dc0) /* SUBAW */
197 frame_base_offset_to_sp += ucst5 << 2;
198 else if ((inst & 0x1ffc) == 0x1bc0) /* SUBAH */
199 frame_base_offset_to_sp += ucst5 << 1;
200 else if ((inst & 0x0ffc) == 0x9c0) /* SUB */
201 frame_base_offset_to_sp += ucst5;
203 gdb_assert_not_reached ("unexpected instruction");
208 else if ((inst & 0x174) == 0x74) /* stw SRC, *+b15(uconst) */
210 /* The y bit determines which file base is read from. */
211 base_reg = tic6x_register_number ((inst >> 18) & 0x1f,
214 if (base_reg == TIC6X_SP_REGNUM)
216 src_reg = tic6x_register_number ((inst >> 23) & 0x1f,
217 INST_S_BIT (inst), 0);
219 cache->reg_saved[src_reg] = ((inst >> 13) & 0x1f) << 2;
223 non_stw_insn_counter = 0;
227 non_stw_insn_counter++;
228 /* Following instruction sequence may be emitted in prologue:
230 <+0>: subah .D2 b15,28,b15
231 <+4>: or .L2X 0,a4,b0
232 <+8>: || stw .D2T2 b14,*+b15(56)
233 <+12>:[!b0] b .S1 0xe50e4c1c <sleep+220>
234 <+16>:|| stw .D2T1 a10,*+b15(48)
235 <+20>:stw .D2T2 b3,*+b15(52)
236 <+24>:stw .D2T1 a4,*+b15(40)
238 we should look forward for next instruction instead of breaking loop
239 here. So far, we allow almost two sequential non-stw instructions
241 if (non_stw_insn_counter >= 2)
248 /* Step 2: Skip insn on setting up dsbt if it is. Usually, it looks like,
249 ldw .D2T2 *+b14(0),b14 */
250 inst = tic6x_fetch_instruction (gdbarch, pc);
251 /* The s bit determines which file dst will be loaded into, same effect as
253 dst_reg = tic6x_register_number ((inst >> 23) & 0x1f, (inst >> 1) & 1, 0);
254 /* The y bit (bit 7), instead of s bit, determines which file base be
256 base_reg = tic6x_register_number ((inst >> 18) & 0x1f, (inst >> 7) & 1, 0);
258 if ((inst & 0x164) == 0x64 /* ldw */
259 && dst_reg == TIC6X_DP_REGNUM /* dst is B14 */
260 && base_reg == TIC6X_DP_REGNUM) /* baseR is B14 */
267 cache->base = get_frame_register_unsigned (this_frame, TIC6X_SP_REGNUM);
269 if (cache->reg_saved[TIC6X_FP_REGNUM] != -1)
271 /* If the FP now holds an offset from the CFA then this is a frame
272 which uses the frame pointer. */
274 cache->cfa = get_frame_register_unsigned (this_frame,
279 /* FP doesn't hold an offset from the CFA. If SP still holds an
280 offset from the CFA then we might be in a function which omits
281 the frame pointer. */
283 cache->cfa = cache->base + frame_base_offset_to_sp;
287 /* Adjust all the saved registers such that they contain addresses
288 instead of offsets. */
289 for (i = 0; i < TIC6X_NUM_CORE_REGS; i++)
290 if (cache->reg_saved[i] != -1)
291 cache->reg_saved[i] = cache->base + cache->reg_saved[i];
296 /* This is the implementation of gdbarch method skip_prologue. */
299 tic6x_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR start_pc)
302 struct tic6x_unwind_cache cache;
304 /* See if we can determine the end of the prologue via the symbol table.
305 If so, then return either PC, or the PC after the prologue, whichever is
307 if (find_pc_partial_function (start_pc, NULL, &func_addr, NULL))
309 CORE_ADDR post_prologue_pc
310 = skip_prologue_using_sal (gdbarch, func_addr);
311 if (post_prologue_pc != 0)
312 return std::max (start_pc, post_prologue_pc);
315 /* Can't determine prologue from the symbol table, need to examine
317 return tic6x_analyze_prologue (gdbarch, start_pc, (CORE_ADDR) -1, &cache,
321 /* Implement the breakpoint_kind_from_pc gdbarch method. */
324 tic6x_breakpoint_kind_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr)
329 /* Implement the sw_breakpoint_from_kind gdbarch method. */
331 static const gdb_byte *
332 tic6x_sw_breakpoint_from_kind (struct gdbarch *gdbarch, int kind, int *size)
334 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
338 if (tdep == NULL || tdep->breakpoint == NULL)
340 if (BFD_ENDIAN_BIG == gdbarch_byte_order_for_code (gdbarch))
341 return tic6x_bkpt_illegal_opcode_be;
343 return tic6x_bkpt_illegal_opcode_le;
346 return tdep->breakpoint;
350 tic6x_dwarf2_frame_init_reg (struct gdbarch *gdbarch, int regnum,
351 struct dwarf2_frame_state_reg *reg,
352 struct frame_info *this_frame)
354 /* Mark the PC as the destination for the return address. */
355 if (regnum == gdbarch_pc_regnum (gdbarch))
356 reg->how = DWARF2_FRAME_REG_RA;
358 /* Mark the stack pointer as the call frame address. */
359 else if (regnum == gdbarch_sp_regnum (gdbarch))
360 reg->how = DWARF2_FRAME_REG_CFA;
362 /* The above was taken from the default init_reg in dwarf2-frame.c
363 while the below is c6x specific. */
365 /* Callee save registers. The ABI designates A10-A15 and B10-B15 as
367 else if ((regnum >= 10 && regnum <= 15) || (regnum >= 26 && regnum <= 31))
368 reg->how = DWARF2_FRAME_REG_SAME_VALUE;
370 /* All other registers are caller-save. */
371 reg->how = DWARF2_FRAME_REG_UNDEFINED;
374 /* This is the implementation of gdbarch method unwind_pc. */
377 tic6x_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
381 frame_unwind_register (next_frame, TIC6X_PC_REGNUM, buf);
382 return extract_typed_address (buf, builtin_type (gdbarch)->builtin_func_ptr);
385 /* This is the implementation of gdbarch method unwind_sp. */
388 tic6x_unwind_sp (struct gdbarch *gdbarch, struct frame_info *this_frame)
390 return frame_unwind_register_unsigned (this_frame, TIC6X_SP_REGNUM);
394 /* Frame base handling. */
396 static struct tic6x_unwind_cache*
397 tic6x_frame_unwind_cache (struct frame_info *this_frame,
398 void **this_prologue_cache)
400 struct gdbarch *gdbarch = get_frame_arch (this_frame);
401 CORE_ADDR current_pc;
402 struct tic6x_unwind_cache *cache;
404 if (*this_prologue_cache)
405 return (struct tic6x_unwind_cache *) *this_prologue_cache;
407 cache = FRAME_OBSTACK_ZALLOC (struct tic6x_unwind_cache);
408 (*this_prologue_cache) = cache;
410 cache->return_regnum = TIC6X_RA_REGNUM;
412 tic6x_setup_default (cache);
414 cache->pc = get_frame_func (this_frame);
415 current_pc = get_frame_pc (this_frame);
417 /* Prologue analysis does the rest... */
419 tic6x_analyze_prologue (gdbarch, cache->pc, current_pc, cache, this_frame);
425 tic6x_frame_this_id (struct frame_info *this_frame, void **this_cache,
426 struct frame_id *this_id)
428 struct tic6x_unwind_cache *cache =
429 tic6x_frame_unwind_cache (this_frame, this_cache);
431 /* This marks the outermost frame. */
432 if (cache->base == 0)
435 (*this_id) = frame_id_build (cache->cfa, cache->pc);
438 static struct value *
439 tic6x_frame_prev_register (struct frame_info *this_frame, void **this_cache,
442 struct tic6x_unwind_cache *cache =
443 tic6x_frame_unwind_cache (this_frame, this_cache);
445 gdb_assert (regnum >= 0);
447 /* The PC of the previous frame is stored in the RA register of
448 the current frame. Frob regnum so that we pull the value from
449 the correct place. */
450 if (regnum == TIC6X_PC_REGNUM)
451 regnum = cache->return_regnum;
453 if (regnum == TIC6X_SP_REGNUM && cache->cfa)
454 return frame_unwind_got_constant (this_frame, regnum, cache->cfa);
456 /* If we've worked out where a register is stored then load it from
458 if (regnum < TIC6X_NUM_CORE_REGS && cache->reg_saved[regnum] != -1)
459 return frame_unwind_got_memory (this_frame, regnum,
460 cache->reg_saved[regnum]);
462 return frame_unwind_got_register (this_frame, regnum, regnum);
466 tic6x_frame_base_address (struct frame_info *this_frame, void **this_cache)
468 struct tic6x_unwind_cache *info
469 = tic6x_frame_unwind_cache (this_frame, this_cache);
473 static const struct frame_unwind tic6x_frame_unwind =
476 default_frame_unwind_stop_reason,
478 tic6x_frame_prev_register,
480 default_frame_sniffer
483 static const struct frame_base tic6x_frame_base =
486 tic6x_frame_base_address,
487 tic6x_frame_base_address,
488 tic6x_frame_base_address
492 static struct tic6x_unwind_cache *
493 tic6x_make_stub_cache (struct frame_info *this_frame)
495 struct tic6x_unwind_cache *cache;
497 cache = FRAME_OBSTACK_ZALLOC (struct tic6x_unwind_cache);
499 cache->return_regnum = TIC6X_RA_REGNUM;
501 tic6x_setup_default (cache);
503 cache->cfa = get_frame_register_unsigned (this_frame, TIC6X_SP_REGNUM);
509 tic6x_stub_this_id (struct frame_info *this_frame, void **this_cache,
510 struct frame_id *this_id)
512 struct tic6x_unwind_cache *cache;
514 if (*this_cache == NULL)
515 *this_cache = tic6x_make_stub_cache (this_frame);
516 cache = (struct tic6x_unwind_cache *) *this_cache;
518 *this_id = frame_id_build (cache->cfa, get_frame_pc (this_frame));
522 tic6x_stub_unwind_sniffer (const struct frame_unwind *self,
523 struct frame_info *this_frame,
524 void **this_prologue_cache)
526 CORE_ADDR addr_in_block;
528 addr_in_block = get_frame_address_in_block (this_frame);
529 if (in_plt_section (addr_in_block))
535 static const struct frame_unwind tic6x_stub_unwind =
538 default_frame_unwind_stop_reason,
540 tic6x_frame_prev_register,
542 tic6x_stub_unwind_sniffer
545 /* Return the instruction on address PC. */
548 tic6x_fetch_instruction (struct gdbarch *gdbarch, CORE_ADDR pc)
550 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
551 return read_memory_unsigned_integer (pc, TIC6X_OPCODE_SIZE, byte_order);
554 /* Compute the condition of INST if it is a conditional instruction. Always
555 return 1 if INST is not a conditional instruction. */
558 tic6x_condition_true (struct regcache *regcache, unsigned long inst)
562 static const int register_numbers[8] = { -1, 16, 17, 18, 1, 2, 0, -1 };
564 register_number = register_numbers[(inst >> 29) & 7];
565 if (register_number == -1)
568 register_value = regcache_raw_get_signed (regcache, register_number);
569 if ((inst & 0x10000000) != 0)
570 return register_value == 0;
571 return register_value != 0;
574 /* Get the register number by decoding raw bits REG, SIDE, and CROSSPATH in
578 tic6x_register_number (int reg, int side, int crosspath)
580 int r = (reg & 15) | ((crosspath ^ side) << 4);
581 if ((reg & 16) != 0) /* A16 - A31, B16 - B31 */
587 tic6x_extract_signed_field (int value, int low_bit, int bits)
589 int mask = (1 << bits) - 1;
590 int r = (value >> low_bit) & mask;
591 if ((r & (1 << (bits - 1))) != 0)
596 /* Determine where to set a single step breakpoint. */
599 tic6x_get_next_pc (struct regcache *regcache, CORE_ADDR pc)
601 struct gdbarch *gdbarch = get_regcache_arch (regcache);
608 inst = tic6x_fetch_instruction (gdbarch, pc);
612 if (inst == TIC6X_INST_SWE)
614 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
616 if (tdep->syscall_next_pc != NULL)
617 return tdep->syscall_next_pc (get_current_frame ());
620 if (tic6x_condition_true (regcache, inst))
622 if ((inst & 0x0000007c) == 0x00000010)
624 /* B with displacement */
625 pc &= ~(TIC6X_FETCH_PACKET_SIZE - 1);
626 pc += tic6x_extract_signed_field (inst, 7, 21) << 2;
629 if ((inst & 0x0f83effc) == 0x00000360)
631 /* B with register */
633 register_number = tic6x_register_number ((inst >> 18) & 0x1f,
636 pc = regcache_raw_get_unsigned (regcache, register_number);
639 if ((inst & 0x00001ffc) == 0x00001020)
642 register_number = tic6x_register_number ((inst >> 23) & 0x1f,
643 INST_S_BIT (inst), 0);
644 if (regcache_raw_get_signed (regcache, register_number) >= 0)
646 pc &= ~(TIC6X_FETCH_PACKET_SIZE - 1);
647 pc += tic6x_extract_signed_field (inst, 7, 10) << 2;
651 if ((inst & 0x00001ffc) == 0x00000120)
653 /* BNOP with displacement */
654 pc &= ~(TIC6X_FETCH_PACKET_SIZE - 1);
655 pc += tic6x_extract_signed_field (inst, 16, 12) << 2;
658 if ((inst & 0x0f830ffe) == 0x00800362)
660 /* BNOP with register */
661 register_number = tic6x_register_number ((inst >> 18) & 0x1f,
662 1, INST_X_BIT (inst));
663 pc = regcache_raw_get_unsigned (regcache, register_number);
666 if ((inst & 0x00001ffc) == 0x00000020)
669 register_number = tic6x_register_number ((inst >> 23) & 0x1f,
670 INST_S_BIT (inst), 0);
671 if (regcache_raw_get_signed (regcache, register_number) >= 0)
673 pc &= ~(TIC6X_FETCH_PACKET_SIZE - 1);
674 pc += tic6x_extract_signed_field (inst, 13, 10) << 2;
678 if ((inst & 0xf000007c) == 0x10000010)
681 pc &= ~(TIC6X_FETCH_PACKET_SIZE - 1);
682 pc += tic6x_extract_signed_field (inst, 7, 21) << 2;
686 pc += TIC6X_OPCODE_SIZE;
692 /* This is the implementation of gdbarch method software_single_step. */
694 static std::vector<CORE_ADDR>
695 tic6x_software_single_step (struct regcache *regcache)
697 CORE_ADDR next_pc = tic6x_get_next_pc (regcache, regcache_read_pc (regcache));
702 /* This is the implementation of gdbarch method frame_align. */
705 tic6x_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
707 return align_down (addr, 8);
710 /* Given a return value in REGCACHE with a type VALTYPE, extract and copy its
711 value into VALBUF. */
714 tic6x_extract_return_value (struct type *valtype, struct regcache *regcache,
715 enum bfd_endian byte_order, gdb_byte *valbuf)
717 int len = TYPE_LENGTH (valtype);
719 /* pointer types are returned in register A4,
720 up to 32-bit types in A4
721 up to 64-bit types in A5:A4 */
725 - one-byte structure or union occupies the LSB of single even register.
726 - for two-byte structure or union, the first byte occupies byte 1 of
727 register and the second byte occupies byte 0.
728 so, we read the contents in VAL from the LSBs of register. */
729 if (len < 3 && byte_order == BFD_ENDIAN_BIG)
730 regcache_cooked_read_part (regcache, TIC6X_A4_REGNUM, 4 - len, len,
733 regcache_cooked_read (regcache, TIC6X_A4_REGNUM, valbuf);
737 /* For a 5-8 byte structure or union in big-endian, the first byte
738 occupies byte 3 (the MSB) of the upper (odd) register and the
739 remaining bytes fill the decreasingly significant bytes. 5-7
740 byte structures or unions have padding in the LSBs of the
741 lower (even) register. */
742 if (byte_order == BFD_ENDIAN_BIG)
744 regcache_cooked_read (regcache, TIC6X_A4_REGNUM, valbuf + 4);
745 regcache_cooked_read (regcache, TIC6X_A5_REGNUM, valbuf);
749 regcache_cooked_read (regcache, TIC6X_A4_REGNUM, valbuf);
750 regcache_cooked_read (regcache, TIC6X_A5_REGNUM, valbuf + 4);
755 /* Write into appropriate registers a function return value
756 of type TYPE, given in virtual format. */
759 tic6x_store_return_value (struct type *valtype, struct regcache *regcache,
760 enum bfd_endian byte_order, const gdb_byte *valbuf)
762 int len = TYPE_LENGTH (valtype);
764 /* return values of up to 8 bytes are returned in A5:A4 */
768 if (len < 3 && byte_order == BFD_ENDIAN_BIG)
769 regcache_cooked_write_part (regcache, TIC6X_A4_REGNUM, 4 - len, len,
772 regcache_cooked_write (regcache, TIC6X_A4_REGNUM, valbuf);
776 if (byte_order == BFD_ENDIAN_BIG)
778 regcache_cooked_write (regcache, TIC6X_A4_REGNUM, valbuf + 4);
779 regcache_cooked_write (regcache, TIC6X_A5_REGNUM, valbuf);
783 regcache_cooked_write (regcache, TIC6X_A4_REGNUM, valbuf);
784 regcache_cooked_write (regcache, TIC6X_A5_REGNUM, valbuf + 4);
789 /* This is the implementation of gdbarch method return_value. */
791 static enum return_value_convention
792 tic6x_return_value (struct gdbarch *gdbarch, struct value *function,
793 struct type *type, struct regcache *regcache,
794 gdb_byte *readbuf, const gdb_byte *writebuf)
796 /* In C++, when function returns an object, even its size is small
797 enough, it stii has to be passed via reference, pointed by register
799 if (current_language->la_language == language_cplus)
803 type = check_typedef (type);
804 if (language_pass_by_reference (type))
805 return RETURN_VALUE_STRUCT_CONVENTION;
809 if (TYPE_LENGTH (type) > 8)
810 return RETURN_VALUE_STRUCT_CONVENTION;
813 tic6x_extract_return_value (type, regcache,
814 gdbarch_byte_order (gdbarch), readbuf);
816 tic6x_store_return_value (type, regcache,
817 gdbarch_byte_order (gdbarch), writebuf);
819 return RETURN_VALUE_REGISTER_CONVENTION;
822 /* This is the implementation of gdbarch method dummy_id. */
824 static struct frame_id
825 tic6x_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
827 return frame_id_build
828 (get_frame_register_unsigned (this_frame, TIC6X_SP_REGNUM),
829 get_frame_pc (this_frame));
832 /* Get the alignment requirement of TYPE. */
835 tic6x_arg_type_alignment (struct type *type)
837 int len = TYPE_LENGTH (check_typedef (type));
838 enum type_code typecode = TYPE_CODE (check_typedef (type));
840 if (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION)
842 /* The stack alignment of a structure (and union) passed by value is the
843 smallest power of two greater than or equal to its size.
844 This cannot exceed 8 bytes, which is the largest allowable size for
845 a structure passed by value. */
854 gdb_assert_not_reached ("unexpected length of data");
862 if (typecode == TYPE_CODE_COMPLEX)
869 if (typecode == TYPE_CODE_COMPLEX)
875 internal_error (__FILE__, __LINE__, _("unexpected length %d of type"),
880 /* This is the implementation of gdbarch method push_dummy_call. */
883 tic6x_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
884 struct regcache *regcache, CORE_ADDR bp_addr,
885 int nargs, struct value **args, CORE_ADDR sp,
886 int struct_return, CORE_ADDR struct_addr)
890 int stack_offset = 4;
891 int references_offset = 4;
892 CORE_ADDR func_addr = find_function_addr (function, NULL);
893 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
894 struct type *func_type = value_type (function);
895 /* The first arg passed on stack. Mostly the first 10 args are passed by
897 int first_arg_on_stack = 10;
899 /* Set the return address register to point to the entry point of
900 the program, where a breakpoint lies in wait. */
901 regcache_cooked_write_unsigned (regcache, TIC6X_RA_REGNUM, bp_addr);
903 /* The caller must pass an argument in A3 containing a destination address
904 for the returned value. The callee returns the object by copying it to
905 the address in A3. */
907 regcache_cooked_write_unsigned (regcache, 3, struct_addr);
909 /* Determine the type of this function. */
910 func_type = check_typedef (func_type);
911 if (TYPE_CODE (func_type) == TYPE_CODE_PTR)
912 func_type = check_typedef (TYPE_TARGET_TYPE (func_type));
914 gdb_assert (TYPE_CODE (func_type) == TYPE_CODE_FUNC
915 || TYPE_CODE (func_type) == TYPE_CODE_METHOD);
917 /* For a variadic C function, the last explicitly declared argument and all
918 remaining arguments are passed on the stack. */
919 if (TYPE_VARARGS (func_type))
920 first_arg_on_stack = TYPE_NFIELDS (func_type) - 1;
922 /* Now make space on the stack for the args. */
923 for (argnum = 0; argnum < nargs; argnum++)
925 int len = align_up (TYPE_LENGTH (value_type (args[argnum])), 4);
926 if (argnum >= 10 - argreg)
927 references_offset += len;
931 /* SP should be 8-byte aligned, see C6000 ABI section 4.4.1
933 sp = align_down (sp, 8);
936 /* Now load as many as possible of the first arguments into
937 registers, and push the rest onto the stack. Loop through args
938 from first to last. */
939 for (argnum = 0; argnum < nargs; argnum++)
942 struct value *arg = args[argnum];
943 struct type *arg_type = check_typedef (value_type (arg));
944 int len = TYPE_LENGTH (arg_type);
945 enum type_code typecode = TYPE_CODE (arg_type);
947 val = value_contents (arg);
949 /* Copy the argument to general registers or the stack in
950 register-sized pieces. */
951 if (argreg < first_arg_on_stack)
955 if (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION)
958 - one-byte structure or union occupies the LSB of single
960 - for two-byte structure or union, the first byte
961 occupies byte 1 of register and the second byte occupies
963 so, we write the contents in VAL to the lsp of
965 if (len < 3 && byte_order == BFD_ENDIAN_BIG)
966 regcache_cooked_write_part (regcache, arg_regs[argreg],
969 regcache_cooked_write (regcache, arg_regs[argreg], val);
973 /* The argument is being passed by value in a single
975 CORE_ADDR regval = extract_unsigned_integer (val, len,
978 regcache_cooked_write_unsigned (regcache, arg_regs[argreg],
986 if (typecode == TYPE_CODE_STRUCT
987 || typecode == TYPE_CODE_UNION)
989 /* For a 5-8 byte structure or union in big-endian, the
990 first byte occupies byte 3 (the MSB) of the upper (odd)
991 register and the remaining bytes fill the decreasingly
992 significant bytes. 5-7 byte structures or unions have
993 padding in the LSBs of the lower (even) register. */
994 if (byte_order == BFD_ENDIAN_BIG)
996 regcache_cooked_write (regcache,
997 arg_regs[argreg] + 1, val);
998 regcache_cooked_write_part (regcache,
1004 regcache_cooked_write (regcache, arg_regs[argreg],
1006 regcache_cooked_write_part (regcache,
1007 arg_regs[argreg] + 1, 0,
1013 /* The argument is being passed by value in a pair of
1015 ULONGEST regval = extract_unsigned_integer (val, len,
1018 regcache_cooked_write_unsigned (regcache,
1021 regcache_cooked_write_unsigned (regcache,
1022 arg_regs[argreg] + 1,
1028 /* The argument is being passed by reference in a single
1032 /* It is not necessary to adjust REFERENCES_OFFSET to
1033 8-byte aligned in some cases, in which 4-byte alignment
1034 is sufficient. For simplicity, we adjust
1035 REFERENCES_OFFSET to 8-byte aligned. */
1036 references_offset = align_up (references_offset, 8);
1038 addr = sp + references_offset;
1039 write_memory (addr, val, len);
1040 references_offset += align_up (len, 4);
1041 regcache_cooked_write_unsigned (regcache, arg_regs[argreg],
1049 /* The argument is being passed on the stack. */
1052 /* There are six different cases of alignment, and these rules can
1053 be found in tic6x_arg_type_alignment:
1055 1) 4-byte aligned if size is less than or equal to 4 byte, such
1056 as short, int, struct, union etc.
1057 2) 8-byte aligned if size is less than or equal to 8-byte, such
1058 as double, long long,
1059 3) 4-byte aligned if it is of type _Complex float, even its size
1061 4) 8-byte aligned if it is of type _Complex double or _Complex
1062 long double, even its size is 16-byte. Because, the address of
1063 variable is passed as reference.
1064 5) struct and union larger than 8-byte are passed by reference, so
1065 it is 4-byte aligned.
1066 6) struct and union of size between 4 byte and 8 byte varies.
1067 alignment of struct variable is the alignment of its first field,
1068 while alignment of union variable is the max of all its fields'
1072 ; /* Default is 4-byte aligned. Nothing to be done. */
1074 stack_offset = align_up (stack_offset,
1075 tic6x_arg_type_alignment (arg_type));
1078 /* _Complex double or _Complex long double */
1079 if (typecode == TYPE_CODE_COMPLEX)
1081 /* The argument is being passed by reference on stack. */
1083 references_offset = align_up (references_offset, 8);
1085 addr = sp + references_offset;
1086 /* Store variable on stack. */
1087 write_memory (addr, val, len);
1089 references_offset += align_up (len, 4);
1091 /* Pass the address of variable on stack as reference. */
1092 store_unsigned_integer ((gdb_byte *) val, 4, byte_order,
1098 internal_error (__FILE__, __LINE__,
1099 _("unexpected type %d of arg %d"),
1103 internal_error (__FILE__, __LINE__,
1104 _("unexpected length %d of arg %d"), len, argnum);
1106 addr = sp + stack_offset;
1107 write_memory (addr, val, len);
1108 stack_offset += align_up (len, 4);
1112 regcache_cooked_write_signed (regcache, TIC6X_SP_REGNUM, sp);
1114 /* Return adjusted stack pointer. */
1118 /* This is the implementation of gdbarch method stack_frame_destroyed_p. */
1121 tic6x_stack_frame_destroyed_p (struct gdbarch *gdbarch, CORE_ADDR pc)
1123 unsigned long inst = tic6x_fetch_instruction (gdbarch, pc);
1124 /* Normally, the epilogue is composed by instruction `b .S2 b3'. */
1125 if ((inst & 0x0f83effc) == 0x360)
1127 unsigned int src2 = tic6x_register_number ((inst >> 18) & 0x1f,
1130 if (src2 == TIC6X_RA_REGNUM)
1137 /* This is the implementation of gdbarch method get_longjmp_target. */
1140 tic6x_get_longjmp_target (struct frame_info *frame, CORE_ADDR *pc)
1142 struct gdbarch *gdbarch = get_frame_arch (frame);
1143 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
1147 /* JMP_BUF is passed by reference in A4. */
1148 jb_addr = get_frame_register_unsigned (frame, 4);
1150 /* JMP_BUF contains 13 elements of type int, and return address is stored
1151 in the last slot. */
1152 if (target_read_memory (jb_addr + 12 * 4, buf, 4))
1155 *pc = extract_unsigned_integer (buf, 4, byte_order);
1160 /* This is the implementation of gdbarch method
1161 return_in_first_hidden_param_p. */
1164 tic6x_return_in_first_hidden_param_p (struct gdbarch *gdbarch,
1170 static struct gdbarch *
1171 tic6x_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
1173 struct gdbarch *gdbarch;
1174 struct gdbarch_tdep *tdep;
1175 struct tdesc_arch_data *tdesc_data = NULL;
1176 const struct target_desc *tdesc = info.target_desc;
1179 /* Check any target description for validity. */
1180 if (tdesc_has_registers (tdesc))
1182 const struct tdesc_feature *feature;
1185 feature = tdesc_find_feature (tdesc, "org.gnu.gdb.tic6x.core");
1187 if (feature == NULL)
1190 tdesc_data = tdesc_data_alloc ();
1193 for (i = 0; i < 32; i++) /* A0 - A15, B0 - B15 */
1194 valid_p &= tdesc_numbered_register (feature, tdesc_data, i,
1195 tic6x_register_names[i]);
1198 valid_p &= tdesc_numbered_register (feature, tdesc_data, i++,
1199 tic6x_register_names[TIC6X_CSR_REGNUM]);
1200 valid_p &= tdesc_numbered_register (feature, tdesc_data, i++,
1201 tic6x_register_names[TIC6X_PC_REGNUM]);
1205 tdesc_data_cleanup (tdesc_data);
1209 feature = tdesc_find_feature (tdesc, "org.gnu.gdb.tic6x.gp");
1213 static const char *const gp[] =
1215 "A16", "A17", "A18", "A19", "A20", "A21", "A22", "A23",
1216 "A24", "A25", "A26", "A27", "A28", "A29", "A30", "A31",
1217 "B16", "B17", "B18", "B19", "B20", "B21", "B22", "B23",
1218 "B24", "B25", "B26", "B27", "B28", "B29", "B30", "B31",
1223 for (j = 0; j < 32; j++) /* A16 - A31, B16 - B31 */
1224 valid_p &= tdesc_numbered_register (feature, tdesc_data, i++,
1229 tdesc_data_cleanup (tdesc_data);
1234 feature = tdesc_find_feature (tdesc, "org.gnu.gdb.tic6x.c6xp");
1237 valid_p &= tdesc_numbered_register (feature, tdesc_data, i++, "TSR");
1238 valid_p &= tdesc_numbered_register (feature, tdesc_data, i++, "ILC");
1239 valid_p &= tdesc_numbered_register (feature, tdesc_data, i++, "RILC");
1243 tdesc_data_cleanup (tdesc_data);
1250 /* Find a candidate among extant architectures. */
1251 for (arches = gdbarch_list_lookup_by_info (arches, &info);
1253 arches = gdbarch_list_lookup_by_info (arches->next, &info))
1255 tdep = gdbarch_tdep (arches->gdbarch);
1257 if (has_gp != tdep->has_gp)
1260 if (tdep && tdep->breakpoint)
1261 return arches->gdbarch;
1264 tdep = XCNEW (struct gdbarch_tdep);
1266 tdep->has_gp = has_gp;
1267 gdbarch = gdbarch_alloc (&info, tdep);
1269 /* Data type sizes. */
1270 set_gdbarch_ptr_bit (gdbarch, 32);
1271 set_gdbarch_addr_bit (gdbarch, 32);
1272 set_gdbarch_short_bit (gdbarch, 16);
1273 set_gdbarch_int_bit (gdbarch, 32);
1274 set_gdbarch_long_bit (gdbarch, 32);
1275 set_gdbarch_long_long_bit (gdbarch, 64);
1276 set_gdbarch_float_bit (gdbarch, 32);
1277 set_gdbarch_double_bit (gdbarch, 64);
1279 set_gdbarch_float_format (gdbarch, floatformats_ieee_single);
1280 set_gdbarch_double_format (gdbarch, floatformats_ieee_double);
1282 /* The register set. */
1283 set_gdbarch_num_regs (gdbarch, TIC6X_NUM_REGS);
1284 set_gdbarch_sp_regnum (gdbarch, TIC6X_SP_REGNUM);
1285 set_gdbarch_pc_regnum (gdbarch, TIC6X_PC_REGNUM);
1287 set_gdbarch_register_name (gdbarch, tic6x_register_name);
1288 set_gdbarch_register_type (gdbarch, tic6x_register_type);
1290 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
1292 set_gdbarch_skip_prologue (gdbarch, tic6x_skip_prologue);
1293 set_gdbarch_breakpoint_kind_from_pc (gdbarch,
1294 tic6x_breakpoint_kind_from_pc);
1295 set_gdbarch_sw_breakpoint_from_kind (gdbarch,
1296 tic6x_sw_breakpoint_from_kind);
1298 set_gdbarch_unwind_pc (gdbarch, tic6x_unwind_pc);
1299 set_gdbarch_unwind_sp (gdbarch, tic6x_unwind_sp);
1302 dwarf2_append_unwinders (gdbarch);
1304 frame_unwind_append_unwinder (gdbarch, &tic6x_stub_unwind);
1305 frame_unwind_append_unwinder (gdbarch, &tic6x_frame_unwind);
1306 frame_base_set_default (gdbarch, &tic6x_frame_base);
1308 dwarf2_frame_set_init_reg (gdbarch, tic6x_dwarf2_frame_init_reg);
1310 /* Single stepping. */
1311 set_gdbarch_software_single_step (gdbarch, tic6x_software_single_step);
1313 /* Call dummy code. */
1314 set_gdbarch_frame_align (gdbarch, tic6x_frame_align);
1316 set_gdbarch_return_value (gdbarch, tic6x_return_value);
1318 set_gdbarch_dummy_id (gdbarch, tic6x_dummy_id);
1320 /* Enable inferior call support. */
1321 set_gdbarch_push_dummy_call (gdbarch, tic6x_push_dummy_call);
1323 set_gdbarch_get_longjmp_target (gdbarch, tic6x_get_longjmp_target);
1325 set_gdbarch_stack_frame_destroyed_p (gdbarch, tic6x_stack_frame_destroyed_p);
1327 set_gdbarch_return_in_first_hidden_param_p (gdbarch,
1328 tic6x_return_in_first_hidden_param_p);
1330 /* Hook in ABI-specific overrides, if they have been registered. */
1331 gdbarch_init_osabi (info, gdbarch);
1334 tdesc_use_registers (gdbarch, tdesc, tdesc_data);
1339 /* -Wmissing-prototypes */
1340 extern initialize_file_ftype _initialize_tic6x_tdep;
1343 _initialize_tic6x_tdep (void)
1345 register_gdbarch_init (bfd_arch_tic6x, tic6x_gdbarch_init);
1347 initialize_tdesc_tic6x_c64xp ();
1348 initialize_tdesc_tic6x_c64x ();
1349 initialize_tdesc_tic6x_c62x ();