diff options
Diffstat (limited to 'gdb/hppa-tdep.c')
| -rw-r--r-- | gdb/hppa-tdep.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/gdb/hppa-tdep.c b/gdb/hppa-tdep.c index eb7cef3..425a6e8 100644 --- a/gdb/hppa-tdep.c +++ b/gdb/hppa-tdep.c @@ -2737,6 +2737,223 @@ hppa_frame_prev_register_helper (struct frame_info *next_frame, } +/* An instruction to match. */ +struct insn_pattern +{ + unsigned int data; /* See if it matches this.... */ + unsigned int mask; /* ... with this mask. */ +}; + +/* See bfd/elf32-hppa.c */ +static struct insn_pattern hppa_long_branch_stub[] = { + /* ldil LR'xxx,%r1 */ + { 0x20200000, 0xffe00000 }, + /* be,n RR'xxx(%sr4,%r1) */ + { 0xe0202002, 0xffe02002 }, + { 0, 0 } +}; + +static struct insn_pattern hppa_long_branch_pic_stub[] = { + /* b,l .+8, %r1 */ + { 0xe8200000, 0xffe00000 }, + /* addil LR'xxx - ($PIC_pcrel$0 - 4), %r1 */ + { 0x28200000, 0xffe00000 }, + /* be,n RR'xxxx - ($PIC_pcrel$0 - 8)(%sr4, %r1) */ + { 0xe0202002, 0xffe02002 }, + { 0, 0 } +}; + +static struct insn_pattern hppa_import_stub[] = { + /* addil LR'xxx, %dp */ + { 0x2b600000, 0xffe00000 }, + /* ldw RR'xxx(%r1), %r21 */ + { 0x48350000, 0xffffb000 }, + /* bv %r0(%r21) */ + { 0xeaa0c000, 0xffffffff }, + /* ldw RR'xxx+4(%r1), %r19 */ + { 0x48330000, 0xffffb000 }, + { 0, 0 } +}; + +static struct insn_pattern hppa_import_pic_stub[] = { + /* addil LR'xxx,%r19 */ + { 0x2a600000, 0xffe00000 }, + /* ldw RR'xxx(%r1),%r21 */ + { 0x48350000, 0xffffb000 }, + /* bv %r0(%r21) */ + { 0xeaa0c000, 0xffffffff }, + /* ldw RR'xxx+4(%r1),%r19 */ + { 0x48330000, 0xffffb000 }, + { 0, 0 }, +}; + +static struct insn_pattern hppa_plt_stub[] = { + /* b,l 1b, %r20 - 1b is 3 insns before here */ + { 0xea9f1fdd, 0xffffffff }, + /* depi 0,31,2,%r20 */ + { 0xd6801c1e, 0xffffffff }, + { 0, 0 } +}; + +static struct insn_pattern hppa_sigtramp[] = { + /* ldi 0, %r25 or ldi 1, %r25 */ + { 0x34190000, 0xfffffffd }, + /* ldi __NR_rt_sigreturn, %r20 */ + { 0x3414015a, 0xffffffff }, + /* be,l 0x100(%sr2, %r0), %sr0, %r31 */ + { 0xe4008200, 0xffffffff }, + /* nop */ + { 0x08000240, 0xffffffff }, + { 0, 0 } +}; + +/* Maximum number of instructions on the patterns above. */ +#define HPPA_MAX_INSN_PATTERN_LEN 4 + +/* Return non-zero if the instructions at PC match the series + described in PATTERN, or zero otherwise. PATTERN is an array of + 'struct insn_pattern' objects, terminated by an entry whose mask is + zero. + + When the match is successful, fill INSN[i] with what PATTERN[i] + matched. */ + +static int +hppa_match_insns (CORE_ADDR pc, struct insn_pattern *pattern, + unsigned int *insn) +{ + CORE_ADDR npc = pc; + int i; + + for (i = 0; pattern[i].mask; i++) + { + gdb_byte buf[HPPA_INSN_SIZE]; + + deprecated_read_memory_nobpt (npc, buf, HPPA_INSN_SIZE); + insn[i] = extract_unsigned_integer (buf, HPPA_INSN_SIZE); + if ((insn[i] & pattern[i].mask) == pattern[i].data) + npc += 4; + else + return 0; + } + + return 1; +} + +/* This relaxed version of the insstruction matcher allows us to match + from somewhere inside the pattern, by looking backwards in the + instruction scheme. */ + +static int +hppa_match_insns_relaxed (CORE_ADDR pc, struct insn_pattern *pattern, + unsigned int *insn) +{ + int offset, len = 0; + + while (pattern[len].mask) + len++; + + for (offset = 0; offset < len; offset++) + if (hppa_match_insns (pc - offset * HPPA_INSN_SIZE, pattern, insn)) + return 1; + + return 0; +} + +static int +hppa_in_dyncall (CORE_ADDR pc) +{ + struct unwind_table_entry *u; + + u = find_unwind_entry (hppa_symbol_address ("$$dyncall")); + if (!u) + return 0; + + return (pc >= u->region_start && pc <= u->region_end); +} + +int +hppa_in_solib_call_trampoline (CORE_ADDR pc, char *name) +{ + unsigned int insn[HPPA_MAX_INSN_PATTERN_LEN]; + struct unwind_table_entry *u; + + if (in_plt_section (pc, name) || hppa_in_dyncall (pc)) + return 1; + + /* The GNU toolchain produces linker stubs without unwind + information. Since the pattern matching for linker stubs can be + quite slow, so bail out if we do have an unwind entry. */ + + u = find_unwind_entry (pc); + if (u == NULL) + return 0; + + return (hppa_match_insns_relaxed (pc, hppa_import_stub, insn) + || hppa_match_insns_relaxed (pc, hppa_import_pic_stub, insn) + || hppa_match_insns_relaxed (pc, hppa_long_branch_stub, insn) + || hppa_match_insns_relaxed (pc, hppa_long_branch_pic_stub, insn)); +} + +/* This code skips several kind of "trampolines" used on PA-RISC + systems: $$dyncall, import stubs and PLT stubs. */ + +CORE_ADDR +hppa_skip_trampoline_code (CORE_ADDR pc) +{ + unsigned int insn[HPPA_MAX_INSN_PATTERN_LEN]; + int dp_rel; + + /* $$dyncall handles both PLABELs and direct addresses. */ + if (hppa_in_dyncall (pc)) + { + pc = read_register (HPPA_R0_REGNUM + 22); + + /* PLABELs have bit 30 set; if it's a PLABEL, then dereference it. */ + if (pc & 0x2) + pc = read_memory_typed_address (pc & ~0x3, builtin_type_void_func_ptr); + + return pc; + } + + dp_rel = hppa_match_insns (pc, hppa_import_stub, insn); + if (dp_rel || hppa_match_insns (pc, hppa_import_pic_stub, insn)) + { + /* Extract the target address from the addil/ldw sequence. */ + pc = hppa_extract_21 (insn[0]) + hppa_extract_14 (insn[1]); + + if (dp_rel) + pc += read_register (HPPA_DP_REGNUM); + else + pc += read_register (HPPA_R0_REGNUM + 19); + + /* fallthrough */ + } + + if (in_plt_section (pc, NULL)) + { + pc = read_memory_typed_address (pc, builtin_type_void_func_ptr); + + /* If the PLT slot has not yet been resolved, the target will be + the PLT stub. */ + if (in_plt_section (pc, NULL)) + { + /* Sanity check: are we pointing to the PLT stub? */ + if (!hppa_match_insns (pc, hppa_plt_stub, insn)) + { + warning (_("Cannot resolve PLT stub at 0x%s."), paddr_nz (pc)); + return 0; + } + + /* This should point to the fixup routine. */ + pc = read_memory_typed_address (pc + 8, builtin_type_void_func_ptr); + } + } + + return pc; +} + + /* Here is a table of C type sizes on hppa with various compiles and options. I measured this on PA 9000/800 with HP-UX 11.11 and these compilers: |