/* Motorola m68k target-dependent support for GNU/Linux. Copyright 1996, 1998, 2000, 2001, 2002, 2003 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "defs.h" #include "gdbcore.h" #include "doublest.h" #include "floatformat.h" #include "frame.h" #include "target.h" #include "gdb_string.h" #include "gdbtypes.h" #include "osabi.h" #include "regcache.h" #include "objfiles.h" #include "symtab.h" #include "m68k-tdep.h" /* Offsets (in target ints) into jmp_buf. */ #define M68K_LINUX_JB_ELEMENT_SIZE 4 #define M68K_LINUX_JB_PC 7 /* Check whether insn1 and insn2 are parts of a signal trampoline. */ #define IS_SIGTRAMP(insn1, insn2) \ (/* addaw #20,sp; moveq #119,d0; trap #0 */ \ (insn1 == 0xdefc0014 && insn2 == 0x70774e40) \ /* moveq #119,d0; trap #0 */ \ || insn1 == 0x70774e40) #define IS_RT_SIGTRAMP(insn1, insn2) \ (/* movel #173,d0; trap #0 */ \ (insn1 == 0x203c0000 && insn2 == 0x00ad4e40) \ /* moveq #82,d0; notb d0; trap #0 */ \ || (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40)) /* Return non-zero if PC points into the signal trampoline. For the sake of m68k_linux_get_sigtramp_info we also distinguish between non-RT and RT signal trampolines. */ static int m68k_linux_pc_in_sigtramp (CORE_ADDR pc, char *name) { CORE_ADDR sp; char buf[12]; unsigned long insn0, insn1, insn2; if (read_memory_nobpt (pc - 4, buf, sizeof (buf))) return 0; insn1 = extract_unsigned_integer (buf + 4, 4); insn2 = extract_unsigned_integer (buf + 8, 4); if (IS_SIGTRAMP (insn1, insn2)) return 1; if (IS_RT_SIGTRAMP (insn1, insn2)) return 2; insn0 = extract_unsigned_integer (buf, 4); if (IS_SIGTRAMP (insn0, insn1)) return 1; if (IS_RT_SIGTRAMP (insn0, insn1)) return 2; insn0 = ((insn0 << 16) & 0xffffffff) | (insn1 >> 16); insn1 = ((insn1 << 16) & 0xffffffff) | (insn2 >> 16); if (IS_SIGTRAMP (insn0, insn1)) return 1; if (IS_RT_SIGTRAMP (insn0, insn1)) return 2; return 0; } /* From . */ static int m68k_linux_sigcontext_reg_offset[M68K_NUM_REGS] = { 2 * 4, /* %d0 */ 3 * 4, /* %d1 */ -1, /* %d2 */ -1, /* %d3 */ -1, /* %d4 */ -1, /* %d5 */ -1, /* %d6 */ -1, /* %d7 */ 4 * 4, /* %a0 */ 5 * 4, /* %a1 */ -1, /* %a2 */ -1, /* %a3 */ -1, /* %a4 */ -1, /* %a5 */ -1, /* %fp */ 1 * 4, /* %sp */ 5 * 4 + 2, /* %sr */ 6 * 4 + 2, /* %pc */ 8 * 4, /* %fp0 */ 11 * 4, /* %fp1 */ -1, /* %fp2 */ -1, /* %fp3 */ -1, /* %fp4 */ -1, /* %fp5 */ -1, /* %fp6 */ -1, /* %fp7 */ 14 * 4, /* %fpcr */ 15 * 4, /* %fpsr */ 16 * 4 /* %fpiaddr */ }; /* From . */ static int m68k_linux_ucontext_reg_offset[M68K_NUM_REGS] = { 6 * 4, /* %d0 */ 7 * 4, /* %d1 */ 8 * 4, /* %d2 */ 9 * 4, /* %d3 */ 10 * 4, /* %d4 */ 11 * 4, /* %d5 */ 12 * 4, /* %d6 */ 13 * 4, /* %d7 */ 14 * 4, /* %a0 */ 15 * 4, /* %a1 */ 16 * 4, /* %a2 */ 17 * 4, /* %a3 */ 18 * 4, /* %a4 */ 19 * 4, /* %a5 */ 20 * 4, /* %fp */ 21 * 4, /* %sp */ 23 * 4, /* %sr */ 22 * 4, /* %pc */ 27 * 4, /* %fp0 */ 30 * 4, /* %fp1 */ 33 * 4, /* %fp2 */ 36 * 4, /* %fp3 */ 39 * 4, /* %fp4 */ 42 * 4, /* %fp5 */ 45 * 4, /* %fp6 */ 48 * 4, /* %fp7 */ 24 * 4, /* %fpcr */ 25 * 4, /* %fpsr */ 26 * 4 /* %fpiaddr */ }; /* Get info about saved registers in sigtramp. */ static struct m68k_sigtramp_info m68k_linux_get_sigtramp_info (struct frame_info *next_frame) { CORE_ADDR sp; char buf[4]; struct m68k_sigtramp_info info; frame_unwind_register (next_frame, M68K_SP_REGNUM, buf); sp = extract_unsigned_integer (buf, 4); /* Get sigcontext address, it is the third parameter on the stack. */ info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4); if (m68k_linux_pc_in_sigtramp (frame_pc_unwind (next_frame), 0) == 2) info.sc_reg_offset = m68k_linux_ucontext_reg_offset; else info.sc_reg_offset = m68k_linux_sigcontext_reg_offset; return info; } /* Extract from an array REGBUF containing the (raw) register state, a function return value of TYPE, and copy that, in virtual format, into VALBUF. */ static void m68k_linux_extract_return_value (struct type *type, struct regcache *regcache, void *valbuf) { int len = TYPE_LENGTH (type); char buf[M68K_MAX_REGISTER_SIZE]; if (TYPE_CODE (type) == TYPE_CODE_STRUCT && TYPE_NFIELDS (type) == 1) { m68k_linux_extract_return_value (TYPE_FIELD_TYPE (type, 0), regcache, valbuf); return; } if (TYPE_CODE (type) == TYPE_CODE_FLT) { regcache_raw_read (regcache, M68K_FP0_REGNUM, buf); convert_typed_floating (buf, builtin_type_m68881_ext, valbuf, type); } else if (TYPE_CODE (type) == TYPE_CODE_PTR) regcache_raw_read (regcache, M68K_A0_REGNUM, valbuf); else { if (len <= 4) { regcache_raw_read (regcache, M68K_D0_REGNUM, buf); memcpy (valbuf, buf + (4 - len), len); } else if (len <= 8) { regcache_raw_read (regcache, M68K_D0_REGNUM, buf); memcpy (valbuf, buf + (8 - len), len - 4); regcache_raw_read (regcache, M68K_D1_REGNUM, (char *) valbuf + (len - 4)); } else internal_error (__FILE__, __LINE__, "Cannot extract return value of %d bytes long.", len); } } /* Write into the appropriate registers a function return value stored in VALBUF of type TYPE, given in virtual format. */ static void m68k_linux_store_return_value (struct type *type, struct regcache *regcache, const void *valbuf) { int len = TYPE_LENGTH (type); if (TYPE_CODE (type) == TYPE_CODE_STRUCT && TYPE_NFIELDS (type) == 1) { m68k_linux_store_return_value (TYPE_FIELD_TYPE (type, 0), regcache, valbuf); return; } if (TYPE_CODE (type) == TYPE_CODE_FLT) { char buf[M68K_MAX_REGISTER_SIZE]; convert_typed_floating (valbuf, type, buf, builtin_type_m68881_ext); regcache_raw_write (regcache, M68K_FP0_REGNUM, buf); } else if (TYPE_CODE (type) == TYPE_CODE_PTR) regcache_raw_write (regcache, M68K_A0_REGNUM, valbuf); else { if (len <= 4) regcache_raw_write_part (regcache, M68K_D0_REGNUM, 4 - len, len, valbuf); else if (len <= 8) { regcache_raw_write_part (regcache, M68K_D1_REGNUM, 8 - len, len - 4, valbuf); regcache_raw_write (regcache, M68K_D0_REGNUM, (char *) valbuf + (len - 4)); } else internal_error (__FILE__, __LINE__, "Cannot store return value of %d bytes long.", len); } } /* Extract from an array REGBUF containing the (raw) register state the address in which a function should return its structure value, as a CORE_ADDR. */ static CORE_ADDR m68k_linux_extract_struct_value_address (struct regcache *regcache) { char buf[4]; regcache_cooked_read (regcache, M68K_A0_REGNUM, buf); return extract_unsigned_integer (buf, 4); } static void m68k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) { struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); tdep->jb_pc = M68K_LINUX_JB_PC; tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE; tdep->get_sigtramp_info = m68k_linux_get_sigtramp_info; tdep->struct_return = reg_struct_return; set_gdbarch_extract_return_value (gdbarch, m68k_linux_extract_return_value); set_gdbarch_store_return_value (gdbarch, m68k_linux_store_return_value); set_gdbarch_deprecated_extract_struct_value_address (gdbarch, m68k_linux_extract_struct_value_address); set_gdbarch_deprecated_pc_in_sigtramp (gdbarch, m68k_linux_pc_in_sigtramp); /* Shared library handling. */ set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section); set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target); } void _initialize_m68k_linux_tdep (void) { gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_LINUX, m68k_linux_init_abi); }