[PATCH 4/4] GDB: New target s12z

John Darrington
2018-08-29T14:19:00Z

gdb/
* configure.tgt: Add configuration for s12z.
* s12z-tdep.c: New file.
* NEWS: Mention new target.
---
gdb/Makefile.in | 1 +
gdb/NEWS | 4 +
gdb/configure.tgt | 5 +
gdb/s12z-tdep.c | 446 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 456 insertions(+)
create mode 100644 gdb/s12z-tdep.c

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 118c3c8062..f448d1ee19 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -758,6 +758,7 @@ ALL_TARGET_OBS = \
rs6000-lynx178-tdep.o \
rs6000-tdep.o \
rx-tdep.o \
+ s12z-tdep.o \
s390-linux-tdep.o \
s390-tdep.o \
score-tdep.o \
diff --git a/gdb/NEWS b/gdb/NEWS
index a7a3674375..c46056525a 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,10 @@

*** Changes since GDB 8.2

+* New targets
+
+ NXP S12Z s12z-*-elf
+
* GDB and GDBserver now support IPv6 connections. IPv6 addresses
can be passed using the '[ADDRESS]:PORT' notation, or the regular
'ADDRESS:PORT' method.
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 5e3bd5de71..5573413db4 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -643,6 +643,11 @@ spu*-*-*)
build_gdbserver=yes
;;

+s12z-*-*)
+ # Target: Freescale S12z
+ gdb_target_obs="s12z-tdep.o"
+ ;;
+
tic6x-*-*linux)
# Target: GNU/Linux TI C6x
gdb_target_obs="tic6x-tdep.o tic6x-linux-tdep.o solib-dsbt.o \
diff --git a/gdb/s12z-tdep.c b/gdb/s12z-tdep.c
new file mode 100644
index 0000000000..1df33c0a7c
--- /dev/null
+++ b/gdb/s12z-tdep.c
@@ -0,0 +1,446 @@
+/* Target-dependent code for the S12Z, for the GDB.
+ Copyright (C) 2018 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 3 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, see <http://www.gnu.org/licenses/>. */
+
+/* Much of this file is shamelessly copied from or1k-tdep.c and others */
+
+#include "defs.h"
+
+#include "arch-utils.h"
+#include "dwarf2-frame.h"
+#include "errors.h"
+#include "frame-unwind.h"
+#include "gdbcore.h"
+#include "inferior.h"
+#include "opcode/s12z.h"
+#include "trad-frame.h"
+
+#define N_PHYSICAL_REGISTERS (S12Z_N_REGISTERS - 2)
+
+static const int reg_perm[N_PHYSICAL_REGISTERS] =
+ {
+ REG_D0,
+ REG_D1,
+ REG_D2,
+ REG_D3,
+ REG_D4,
+ REG_D5,
+ REG_D6,
+ REG_D7,
+ REG_X,
+ REG_Y,
+ REG_S,
+ REG_P,
+ REG_CCW
+ };
+
+static const char *
+s12z_register_name (struct gdbarch *gdbarch, int regnum)
+{
+ /* registers is declared in opcodes/s12z.h */
+ return registers[reg_perm[regnum]].name;
+}
+
+static CORE_ADDR
+s12z_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ CORE_ADDR start_pc = 0;
+
+ if (find_pc_partial_function (pc, NULL, &start_pc, NULL))
+ {
+ CORE_ADDR prologue_end = skip_prologue_using_sal (gdbarch, pc);
+
+ if (0 != prologue_end)
+ {
+ struct symtab_and_line prologue_sal = find_pc_line (start_pc, 0);
+ struct compunit_symtab *compunit
+ = SYMTAB_COMPUNIT (prologue_sal.symtab);
+ const char *debug_format = COMPUNIT_DEBUGFORMAT (compunit);
+
+ if ((NULL != debug_format)
+ && (strlen ("dwarf") <= strlen (debug_format))
+ && (0 == strncasecmp ("dwarf", debug_format, strlen ("dwarf"))))
+ return (prologue_end > pc) ? prologue_end : pc;
+ }
+ }
+
+ warning (_("%s Failed to find end of prologue PC = %08x\n"),
+ __FUNCTION__, (unsigned int) pc);
+
+ return 0;
+}
+
+/* Implement the unwind_pc gdbarch method. */
+static CORE_ADDR
+s12z_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, REG_P);
+}
+
+/* Implement the unwind_sp gdbarch method. */
+static CORE_ADDR
+s12z_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, REG_S);
+}
+
+static struct type *
+s12z_register_type (struct gdbarch *gdbarch, int reg_nr)
+{
+ switch (registers[reg_perm[reg_nr]].bytes)
+ {
+ case 1:
+ return builtin_type (gdbarch)->builtin_uint8;
+ case 2:
+ return builtin_type (gdbarch)->builtin_uint16;
+ case 3:
+ return builtin_type (gdbarch)->builtin_uint24;
+ case 4:
+ return builtin_type (gdbarch)->builtin_uint32;
+ default:
+ return builtin_type (gdbarch)->builtin_uint32;
+ }
+ return builtin_type (gdbarch)->builtin_int0;
+}
+
+
+static int
+s12z_dwarf_reg_to_regnum (struct gdbarch *gdbarch, int num)
+{
+ switch (num)
+ {
+ case 15: return REG_S;
+ case 7: return REG_X;
+ case 8: return REG_Y;
+ case 42: return REG_D0;
+ case 43: return REG_D1;
+ case 44: return REG_D2;
+ case 45: return REG_D3;
+ case 46: return REG_D4;
+ case 47: return REG_D5;
+ case 48: return REG_D6;
+ case 49: return REG_D7;
+ }
+ return -1;
+}
+
+
+/* Support functions for frame handling. */
+
+/* Initialize a prologue cache */
+
+static struct trad_frame_cache *
+s12z_frame_cache (struct frame_info *this_frame, void **prologue_cache)
+{
+ int frame_size = 0;
+ struct trad_frame_cache *info;
+
+ CORE_ADDR this_sp;
+ CORE_ADDR this_sp_for_id;
+
+ CORE_ADDR start_addr;
+ CORE_ADDR end_addr;
+
+ /* Nothing to do if we already have this info. */
+ if (NULL != *prologue_cache)
+ return (struct trad_frame_cache *) *prologue_cache;
+
+ /* Get a new prologue cache and populate it with default values. */
+ info = trad_frame_cache_zalloc (this_frame);
+ *prologue_cache = info;
+
+ /* Find the start address of this function (which is a normal frame, even
+ if the next frame is the sentinel frame) and the end of its prologue. */
+ CORE_ADDR this_pc = get_frame_pc (this_frame);
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ find_pc_partial_function (this_pc, NULL, &start_addr, NULL);
+
+ /* Get the stack pointer if we have one (if there's no process executing
+ yet we won't have a frame. */
+ this_sp = (NULL == this_frame) ? 0 :
+ get_frame_register_unsigned (this_frame, REG_S);
+
+ /* Return early if GDB couldn't find the function. */
+ if (start_addr == 0)
+ {
+ warning (_(" couldn't find function\n"));
+
+ /* JPB: 28-Apr-11. This is a temporary patch, to get round GDB
+ crashing right at the beginning. Build the frame ID as best we
+ can. */
+ trad_frame_set_id (info, frame_id_build (this_sp, this_pc));
+
+ return info;
+ }
+
+ /* The default frame base of this frame (for ID purposes only - frame
+ base is an overloaded term) is its stack pointer. For now we use the
+ value of the SP register in this frame. However if the PC is in the
+ prologue of this frame, before the SP has been set up, then the value
+ will actually be that of the prev frame, and we'll need to adjust it
+ later. */
+ trad_frame_set_this_base (info, this_sp);
+ this_sp_for_id = this_sp;
+
+ /* We should only examine code that is in the prologue. This is all code
+ up to (but not including) end_addr. We should only populate the cache
+ while the address is up to (but not including) the PC or end_addr,
+ whichever is first. */
+ end_addr = s12z_skip_prologue (gdbarch, start_addr);
+
+ /* All the following analysis only occurs if we are in the prologue and
+ have executed the code. Check we have a sane prologue size, and if
+ zero we are frameless and can give up here. */
+ if (end_addr < start_addr)
+ error (_("end addr %s is less than start addr %s"),
+ paddress (gdbarch, end_addr), paddress (gdbarch, start_addr));
+
+ if (end_addr == start_addr)
+ frame_size = 0;
+ else
+ {
+ CORE_ADDR addr = start_addr; /* Where we have got to */
+
+ gdb_byte byte;
+
+ if (0 != target_read_code (addr, &byte, 1))
+ memory_error (TARGET_XFER_E_IO, addr);
+
+ int simm;
+ if (byte == 0x1a) /* LEA S, (S, xxxx) */
+ {
+ if (0 != target_read_code (addr + 1, &byte, 1))
+ memory_error (TARGET_XFER_E_IO, addr);
+
+ simm = (signed char) byte;
+ frame_size = -simm;
+ addr += 2;
+
+ /* If the PC has not actually got to this point, then the frame
+ base will be wrong, and we adjust it.
+
+ If we are past this point, then we need to populate the stack
+ accordingly. */
+ if (this_pc <= addr)
+ {
+ /* Only do if executing. */
+ if (0 != this_sp)
+ {
+ this_sp_for_id = this_sp + frame_size;
+ trad_frame_set_this_base (info, this_sp_for_id);
+ }
+ }
+ else
+ {
+ /* We are past this point, so the stack pointer of the prev
+ frame is frame_size greater than the stack pointer of this
+ frame. */
+ trad_frame_set_reg_value (info, REG_S,
+ this_sp + frame_size + 3);
+ }
+ }
+
+ trad_frame_set_reg_addr (info, REG_P, this_sp + frame_size);
+ }
+
+ /* Build the frame ID */
+ trad_frame_set_id (info, frame_id_build (this_sp_for_id, start_addr));
+
+ return info;
+}
+
+/* Implement the this_id function for the stub unwinder. */
+static void
+s12z_frame_this_id (struct frame_info *this_frame,
+ void **prologue_cache, struct frame_id *this_id)
+{
+ struct trad_frame_cache *info = s12z_frame_cache (this_frame,
+ prologue_cache);
+
+ trad_frame_get_id (info, this_id);
+}
+
+
+/* Implement the prev_register function for the stub unwinder. */
+static struct value *
+s12z_frame_prev_register (struct frame_info *this_frame,
+ void **prologue_cache, int regnum)
+{
+ struct trad_frame_cache *info = s12z_frame_cache (this_frame,
+ prologue_cache);
+
+ return trad_frame_get_register (info, this_frame, regnum);
+}
+
+/* Data structures for the normal prologue-analysis-based unwinder. */
+static const struct frame_unwind s12z_frame_unwind = {
+ NORMAL_FRAME,
+ default_frame_unwind_stop_reason,
+ s12z_frame_this_id,
+ s12z_frame_prev_register,
+ NULL,
+ default_frame_sniffer,
+ NULL,
+};
+
+
+constexpr gdb_byte s12z_break_insn[] = {0x00};
+
+typedef BP_MANIPULATION (s12z_break_insn) s12z_breakpoint;
+
+struct gdbarch_tdep
+{
+};
+
+static const char ccw_bits[] =
+ {
+ 'C', /* Carry */
+ 'V', /* Two's Complement Overflow */
+ 'Z', /* Zero */
+ 'N', /* Negative */
+ 'I', /* Interrupt */
+ '-',
+ 'X', /* Non-Maskable Interrupt */
+ 'S', /* STOP Disable */
+ '0', /*
+ '0', * Interrupt priority level
+ '0', */
+ '-',
+ '-',
+ '-',
+ '-',
+ 'U' /* User/Supervisor State */
+ };
+
+/*
+ Print a human readable representation of the CCW register.
+ For example: "u----000SX-Inzvc" corresponds to the value
+ 0xD0
+*/
+static void
+s12z_print_ccw_info (struct gdbarch *gdbarch,
+ struct ui_file *file,
+ struct frame_info *frame,
+ int reg)
+{
+ struct value *v = value_of_register (reg, frame);
+ const char *name = gdbarch_register_name (gdbarch, reg);
+ uint32_t ccw = value_as_long (v);
+ fputs_filtered (name, file);
+ size_t len = strlen (name);
+ const int stop_1 = 15;
+ const int stop_2 = 17;
+ int i;
+ for (i = 0; i < stop_1 - len; ++i)
+ fputc_filtered (' ', file);
+ fprintf_filtered (file, "0x%04x", ccw);
+ for (i = 0; i < stop_2 - len; ++i)
+ fputc_filtered (' ', file);
+ int b;
+ for (b = 15; b >= 0; --b)
+ {
+ if (ccw & (0x1u << b))
+ {
+ if (ccw_bits[b] == 0)
+ fputc_filtered ('1', file);
+ else
+ fputc_filtered (ccw_bits[b], file);
+ }
+ else
+ fputc_filtered (tolower (ccw_bits[b]), file);
+ }
+ fputc_filtered ('\n', file);
+}
+
+static void
+s12z_print_registers_info (struct gdbarch *gdbarch,
+ struct ui_file *file,
+ struct frame_info *frame,
+ int regnum, int print_all)
+{
+ const int numregs = gdbarch_num_regs (gdbarch)
+ + gdbarch_num_pseudo_regs (gdbarch);
+
+ if (regnum == -1)
+ {
+ int reg;
+ for (reg = 0; reg < numregs; reg++)
+ {
+ if (REG_CCW == reg_perm[reg])
+ {
+ s12z_print_ccw_info (gdbarch, file, frame, reg);
+ continue;
+ }
+ default_print_registers_info (gdbarch, file, frame, reg, print_all);
+ }
+ }
+ else if (REG_CCW == reg_perm[regnum])
+ s12z_print_ccw_info (gdbarch, file, frame, regnum);
+ else
+ default_print_registers_info (gdbarch, file, frame, regnum, print_all);
+}
+
+static struct gdbarch *
+s12z_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+ struct gdbarch_tdep *tdep = XNEW (struct gdbarch_tdep);
+ struct gdbarch *gdbarch = gdbarch_alloc (&info, tdep);
+
+ /* Target data types. */
+ set_gdbarch_short_bit (gdbarch, 16);
+ set_gdbarch_int_bit (gdbarch, 16);
+ set_gdbarch_long_bit (gdbarch, 32);
+ set_gdbarch_long_long_bit (gdbarch, 32);
+ set_gdbarch_ptr_bit (gdbarch, 24);
+ set_gdbarch_addr_bit (gdbarch, 24);
+ set_gdbarch_char_signed (gdbarch, 0);
+
+ set_gdbarch_ps_regnum (gdbarch, REG_CCW);
+ set_gdbarch_pc_regnum (gdbarch, REG_P);
+ set_gdbarch_sp_regnum (gdbarch, REG_S);
+
+
+ set_gdbarch_print_registers_info (gdbarch, s12z_print_registers_info);
+
+ set_gdbarch_breakpoint_kind_from_pc (gdbarch,
+ s12z_breakpoint::kind_from_pc);
+ set_gdbarch_sw_breakpoint_from_kind (gdbarch,
+ s12z_breakpoint::bp_from_kind);
+
+ set_gdbarch_num_regs (gdbarch, N_PHYSICAL_REGISTERS);
+ set_gdbarch_register_name (gdbarch, s12z_register_name);
+ set_gdbarch_skip_prologue (gdbarch, s12z_skip_prologue);
+ set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+ set_gdbarch_dwarf2_reg_to_regnum (gdbarch, s12z_dwarf_reg_to_regnum);
+
+ set_gdbarch_register_type (gdbarch, s12z_register_type);
+
+ /* Functions to access frame data. */
+ set_gdbarch_unwind_pc (gdbarch, s12z_unwind_pc);
+ set_gdbarch_unwind_sp (gdbarch, s12z_unwind_sp);
+
+ dwarf2_append_unwinders (gdbarch);
+ frame_unwind_append_unwinder (gdbarch, &s12z_frame_unwind);
+
+ return gdbarch;
+}
+
+void
+_initialize_s12z_tdep (void)
+{
+ gdbarch_register (bfd_arch_s12z, s12z_gdbarch_init, NULL);
+}
--
2.11.0