diff options
Diffstat (limited to 'gdb/moxie-tdep.c')
| -rw-r--r-- | gdb/moxie-tdep.c | 202 |
1 files changed, 184 insertions, 18 deletions
diff --git a/gdb/moxie-tdep.c b/gdb/moxie-tdep.c index 201b50f..6e269a2 100644 --- a/gdb/moxie-tdep.c +++ b/gdb/moxie-tdep.c @@ -285,6 +285,187 @@ struct moxie_unwind_cache struct trad_frame_saved_reg *saved_regs; }; +/* Read an unsigned integer from the inferior, and adjust + endianess. */ +static ULONGEST +moxie_process_readu (CORE_ADDR addr, gdb_byte *buf, + int length, enum bfd_endian byte_order) +{ + if (target_read_memory (addr, buf, length)) + { + if (record_debug) + printf_unfiltered (_("Process record: error reading memory at " + "addr 0x%s len = %d.\n"), + paddress (target_gdbarch (), addr), length); + return -1; + } + + return extract_unsigned_integer (buf, length, byte_order); +} + + +/* Helper macro to extract the signed 10-bit offset from a 16-bit + branch instruction. */ +#define INST2OFFSET(o) ((((signed short)((o & ((1<<10)-1))<<6))>>6)<<1) + +/* Insert a single step breakpoint. */ + +static int +moxie_software_single_step (struct frame_info *frame) +{ + struct gdbarch *gdbarch = get_frame_arch (frame); + struct address_space *aspace = get_frame_address_space (frame); + CORE_ADDR addr; + gdb_byte buf[4]; + uint16_t inst; + uint32_t tmpu32; + ULONGEST fp; + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + struct regcache *regcache = get_current_regcache (); + + addr = get_frame_pc (frame); + + inst = (uint16_t) moxie_process_readu (addr, buf, 2, byte_order); + + /* Decode instruction. */ + if (inst & (1 << 15)) + { + if (inst & (1 << 14)) + { + /* This is a Form 3 instruction. */ + int opcode = (inst >> 10 & 0xf); + + switch (opcode) + { + case 0x00: /* beq */ + case 0x01: /* bne */ + case 0x02: /* blt */ + case 0x03: /* bgt */ + case 0x04: /* bltu */ + case 0x05: /* bgtu */ + case 0x06: /* bge */ + case 0x07: /* ble */ + case 0x08: /* bgeu */ + case 0x09: /* bleu */ + /* Insert breaks on both branches, because we can't currently tell + which way things will go. */ + insert_single_step_breakpoint (gdbarch, aspace, addr + 2); + insert_single_step_breakpoint (gdbarch, aspace, addr + 2 + INST2OFFSET(inst)); + break; + default: + { + /* Do nothing. */ + break; + } + } + } + else + { + /* This is a Form 2 instruction. They are all 16 bits. */ + insert_single_step_breakpoint (gdbarch, aspace, addr + 2); + } + } + else + { + /* This is a Form 1 instruction. */ + int opcode = inst >> 8; + + switch (opcode) + { + /* 16-bit instructions. */ + case 0x00: /* nop */ + case 0x02: /* mov (register-to-register) */ + case 0x05: /* add.l */ + case 0x06: /* push */ + case 0x07: /* pop */ + case 0x0a: /* ld.l (register indirect) */ + case 0x0b: /* st.l */ + case 0x0e: /* cmp */ + case 0x0f: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x1c: /* ld.b (register indirect) */ + case 0x1e: /* st.b */ + case 0x21: /* ld.s (register indirect) */ + case 0x23: /* st.s */ + case 0x26: /* and */ + case 0x27: /* lshr */ + case 0x28: /* ashl */ + case 0x29: /* sub.l */ + case 0x2a: /* neg */ + case 0x2b: /* or */ + case 0x2c: /* not */ + case 0x2d: /* ashr */ + case 0x2e: /* xor */ + case 0x2f: /* mul.l */ + case 0x31: /* div.l */ + case 0x32: /* udiv.l */ + case 0x33: /* mod.l */ + case 0x34: /* umod.l */ + insert_single_step_breakpoint (gdbarch, aspace, addr + 2); + break; + + /* 48-bit instructions. */ + case 0x01: /* ldi.l (immediate) */ + case 0x08: /* lda.l */ + case 0x09: /* sta.l */ + case 0x0c: /* ldo.l */ + case 0x0d: /* sto.l */ + case 0x1b: /* ldi.b (immediate) */ + case 0x1d: /* lda.b */ + case 0x1f: /* sta.b */ + case 0x20: /* ldi.s (immediate) */ + case 0x22: /* lda.s */ + case 0x24: /* sta.s */ + case 0x36: /* ldo.b */ + case 0x37: /* sto.b */ + case 0x38: /* ldo.s */ + case 0x39: /* sto.s */ + insert_single_step_breakpoint (gdbarch, aspace, addr + 6); + break; + + /* Control flow instructions. */ + case 0x03: /* jsra */ + case 0x1a: /* jmpa */ + insert_single_step_breakpoint (gdbarch, aspace, + moxie_process_readu (addr + 2, + buf, 4, + byte_order)); + break; + + case 0x04: /* ret */ + regcache_cooked_read_unsigned (regcache, MOXIE_FP_REGNUM, &fp); + insert_single_step_breakpoint (gdbarch, aspace, + moxie_process_readu (fp + 4, + buf, 4, + byte_order)); + break; + + case 0x19: /* jsr */ + case 0x25: /* jmp */ + regcache_raw_read (regcache, + (inst >> 4) & 0xf, (gdb_byte *) & tmpu32); + insert_single_step_breakpoint (gdbarch, aspace, + tmpu32); + break; + + case 0x30: /* swi */ + case 0x35: /* brk */ + /* Unsupported, for now. */ + break; + } + } + + return 1; +} + /* Implement the "read_pc" gdbarch method. */ static CORE_ADDR @@ -495,24 +676,6 @@ moxie_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame) return frame_id_build (sp, get_frame_pc (this_frame)); } -/* Read an unsigned integer from the inferior, and adjust - endianess. */ -static ULONGEST -moxie_process_readu (CORE_ADDR addr, gdb_byte *buf, - int length, enum bfd_endian byte_order) -{ - if (target_read_memory (addr, buf, length)) - { - if (record_debug) - printf_unfiltered (_("Process record: error reading memory at " - "addr 0x%s len = %d.\n"), - paddress (target_gdbarch (), addr), length); - return -1; - } - - return extract_unsigned_integer (buf, length, byte_order); -} - /* Parse the current instruction and record the values of the registers and memory that will be changed in current instruction to "record_arch_list". Return -1 if something wrong. */ @@ -986,6 +1149,9 @@ moxie_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) /* Hook in the default unwinders. */ frame_unwind_append_unwinder (gdbarch, &moxie_frame_unwind); + /* Single stepping. */ + set_gdbarch_software_single_step (gdbarch, moxie_software_single_step); + /* Support simple overlay manager. */ set_gdbarch_overlay_update (gdbarch, simple_overlay_update); |