--- /dev/null
+/* Target-dependent code for Moxie.
+
+ Copyright (C) 2009 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/>. */
+
+#include "defs.h"
+#include "frame.h"
+#include "frame-unwind.h"
+#include "frame-base.h"
+#include "symtab.h"
+#include "gdbtypes.h"
+#include "gdbcmd.h"
+#include "gdbcore.h"
+#include "gdb_string.h"
+#include "value.h"
+#include "inferior.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "osabi.h"
+#include "language.h"
+#include "arch-utils.h"
+#include "regcache.h"
+#include "trad-frame.h"
+#include "dis-asm.h"
+
+#include "gdb_assert.h"
+
+#include "moxie-tdep.h"
+
+/* Local functions. */
+
+extern void _initialize_moxie_tdep (void);
+
+/* Use an invalid address value as 'not available' marker. */
+enum { REG_UNAVAIL = (CORE_ADDR) -1 };
+
+struct moxie_frame_cache
+{
+ /* Base address. */
+ CORE_ADDR base;
+ CORE_ADDR pc;
+ LONGEST framesize;
+ CORE_ADDR saved_regs[MOXIE_NUM_REGS];
+ CORE_ADDR saved_sp;
+};
+
+/* Implement the "frame_align" gdbarch method. */
+
+static CORE_ADDR
+moxie_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
+{
+ /* Align to the size of an instruction (so that they can safely be
+ pushed onto the stack. */
+ return sp & ~1;
+}
+
+/* Implement the "breakpoint_from_pc" gdbarch method. */
+
+const static unsigned char *
+moxie_breakpoint_from_pc (struct gdbarch *gdbarch,
+ CORE_ADDR *pcptr, int *lenptr)
+{
+ static unsigned char breakpoint[] = { 0x35, 0x00 };
+
+ *lenptr = sizeof (breakpoint);
+ return breakpoint;
+}
+
+/* Moxie register names. */
+
+char *moxie_register_names[] = {
+ "$fp", "$sp", "$r0", "$r1", "$r2",
+ "$r3", "$r4", "$r5", "$r6", "$r7",
+ "$r8", "$r9", "$r10", "$r11", "$r12",
+ "$r13", "$pc", "$cc" };
+
+/* Implement the "register_name" gdbarch method. */
+
+static const char *
+moxie_register_name (struct gdbarch *gdbarch, int reg_nr)
+{
+ if (reg_nr < 0)
+ return NULL;
+ if (reg_nr >= MOXIE_NUM_REGS)
+ return NULL;
+ return moxie_register_names[reg_nr];
+}
+
+/* Implement the "register_type" gdbarch method. */
+
+static struct type *
+moxie_register_type (struct gdbarch *gdbarch, int reg_nr)
+{
+ if (reg_nr == MOXIE_PC_REGNUM)
+ return builtin_type (gdbarch)->builtin_func_ptr;
+ else if (reg_nr == MOXIE_SP_REGNUM || reg_nr == MOXIE_FP_REGNUM)
+ return builtin_type (gdbarch)->builtin_data_ptr;
+ else
+ return builtin_type_int32;
+}
+
+/* Write into appropriate registers a function return value
+ of type TYPE, given in virtual format. */
+
+static void
+moxie_store_return_value (struct type *type, struct regcache *regcache,
+ const void *valbuf)
+{
+ CORE_ADDR regval;
+ int len = TYPE_LENGTH (type);
+
+ /* Things always get returned in RET1_REGNUM, RET2_REGNUM. */
+ regval = extract_unsigned_integer (valbuf, len > 4 ? 4 : len);
+ regcache_cooked_write_unsigned (regcache, RET1_REGNUM, regval);
+ if (len > 4)
+ {
+ regval = extract_unsigned_integer ((gdb_byte *) valbuf + 4, len - 4);
+ regcache_cooked_write_unsigned (regcache, RET1_REGNUM + 1, regval);
+ }
+}
+
+/* Decode the instructions within the given address range. Decide
+ when we must have reached the end of the function prologue. If a
+ frame_info pointer is provided, fill in its saved_regs etc.
+
+ Returns the address of the first instruction after the prologue. */
+
+static CORE_ADDR
+moxie_analyze_prologue (CORE_ADDR start_addr, CORE_ADDR end_addr,
+ struct moxie_frame_cache *cache,
+ struct frame_info *this_frame)
+{
+ CORE_ADDR next_addr;
+ ULONGEST inst, inst2;
+ LONGEST offset;
+ int regnum;
+
+ /* Record where the jsra instruction saves the PC and FP. */
+ cache->saved_regs[MOXIE_PC_REGNUM] = -4;
+ cache->saved_regs[MOXIE_FP_REGNUM] = 0;
+ cache->framesize = 0;
+
+ if (start_addr >= end_addr)
+ return end_addr;
+
+ for (next_addr = start_addr; next_addr < end_addr; )
+ {
+ inst = read_memory_unsigned_integer (next_addr, 2);
+
+ /* Match "push $rN" where N is between 2 and 13 inclusive. */
+ if (inst >= 0x0614 && inst <= 0x061f)
+ {
+ regnum = inst & 0x000f;
+ cache->framesize += 4;
+ cache->saved_regs[regnum] = cache->framesize;
+ next_addr += 2;
+ }
+
+ /* Optional stack allocation for args and local vars <= 4
+ byte. */
+ else if (inst == 0x01f0) /* ldi.l $r12, X */
+ {
+ offset = read_memory_integer (next_addr + 2, 4);
+ inst2 = read_memory_unsigned_integer (next_addr + 6, 2);
+
+ if (inst2 == 0x051f) /* add.l $sp, $r12 */
+ {
+ cache->framesize += offset;
+ }
+
+ return (next_addr + 8);
+ }
+ else /* This is not a prologue instruction. */
+ break;
+ }
+
+ return next_addr;
+}
+
+/* Find the end of function prologue. */
+
+static CORE_ADDR
+moxie_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+ CORE_ADDR func_addr = 0, func_end = 0;
+ char *func_name;
+
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+ if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end))
+ {
+ CORE_ADDR post_prologue_pc = skip_prologue_using_sal (func_addr);
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
+ else
+ {
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
+ struct symtab_and_line sal;
+ struct symbol *sym;
+ struct moxie_frame_cache cache;
+ CORE_ADDR plg_end;
+
+ memset (&cache, 0, sizeof cache);
+
+ plg_end = moxie_analyze_prologue (func_addr,
+ func_end, &cache, NULL);
+ /* Found a function. */
+ sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL);
+ /* Don't use line number debug info for assembly source
+ files. */
+ if (sym && SYMBOL_LANGUAGE (sym) != language_asm)
+ {
+ sal = find_pc_line (func_addr, 0);
+ if (sal.end && sal.end < func_end)
+ {
+ /* Found a line number, use it as end of
+ prologue. */
+ return sal.end;
+ }
+ }
+ /* No useable line symbol. Use result of prologue parsing
+ method. */
+ return plg_end;
+ }
+ }
+
+ /* No function symbol -- just return the PC. */
+ return (CORE_ADDR) pc;
+}
+
+struct moxie_unwind_cache
+{
+ /* The previous frame's inner most stack address. Used as this
+ frame ID's stack_addr. */
+ CORE_ADDR prev_sp;
+ /* The frame's base, optionally used by the high-level debug info. */
+ CORE_ADDR base;
+ int size;
+ /* How far the SP and r13 (FP) have been offset from the start of
+ the stack frame (as defined by the previous frame's stack
+ pointer). */
+ LONGEST sp_offset;
+ LONGEST r13_offset;
+ int uses_frame;
+ /* Table indicating the location of each and every register. */
+ struct trad_frame_saved_reg *saved_regs;
+};
+
+/* Implement the "read_pc" gdbarch method. */
+
+static CORE_ADDR
+moxie_read_pc (struct regcache *regcache)
+{
+ ULONGEST pc;
+
+ regcache_cooked_read_unsigned (regcache, MOXIE_PC_REGNUM, &pc);
+ return pc;
+}
+
+/* Implement the "write_pc" gdbarch method. */
+
+static void
+moxie_write_pc (struct regcache *regcache, CORE_ADDR val)
+{
+ regcache_cooked_write_unsigned (regcache, MOXIE_PC_REGNUM, val);
+}
+
+/* Implement the "unwind_pc" gdbarch method. */
+
+static CORE_ADDR
+moxie_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, MOXIE_SP_REGNUM);
+}
+
+/* Given a return value in `regbuf' with a type `valtype',
+ extract and copy its value into `valbuf'. */
+
+static void
+moxie_extract_return_value (struct type *type, struct regcache *regcache,
+ void *dst)
+{
+ bfd_byte *valbuf = dst;
+ int len = TYPE_LENGTH (type);
+ ULONGEST tmp;
+
+ /* By using store_unsigned_integer we avoid having to do
+ anything special for small big-endian values. */
+ regcache_cooked_read_unsigned (regcache, RET1_REGNUM, &tmp);
+ store_unsigned_integer (valbuf, (len > 4 ? len - 4 : len), tmp);
+
+ /* Ignore return values more than 8 bytes in size because the moxie
+ returns anything more than 8 bytes in the stack. */
+ if (len > 4)
+ {
+ regcache_cooked_read_unsigned (regcache, RET1_REGNUM + 1, &tmp);
+ store_unsigned_integer (valbuf + len - 4, 4, tmp);
+ }
+}
+
+/* Implement the "return_value" gdbarch method. */
+
+static enum return_value_convention
+moxie_return_value (struct gdbarch *gdbarch, struct type *func_type,
+ struct type *valtype, struct regcache *regcache,
+ gdb_byte *readbuf, const gdb_byte *writebuf)
+{
+ if (TYPE_LENGTH (valtype) > 8)
+ return RETURN_VALUE_STRUCT_CONVENTION;
+ else
+ {
+ if (readbuf != NULL)
+ moxie_extract_return_value (valtype, regcache, readbuf);
+ if (writebuf != NULL)
+ moxie_store_return_value (valtype, regcache, writebuf);
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
+}
+
+/* Allocate and initialize a moxie_frame_cache object. */
+
+static struct moxie_frame_cache *
+moxie_alloc_frame_cache (void)
+{
+ struct moxie_frame_cache *cache;
+ int i;
+
+ cache = FRAME_OBSTACK_ZALLOC (struct moxie_frame_cache);
+
+ cache->base = 0;
+ cache->saved_sp = 0;
+ cache->pc = 0;
+ cache->framesize = 0;
+ for (i = 0; i < MOXIE_NUM_REGS; ++i)
+ cache->saved_regs[i] = REG_UNAVAIL;
+
+ return cache;
+}
+
+/* Populate a moxie_frame_cache object for this_frame. */
+
+static struct moxie_frame_cache *
+moxie_frame_cache (struct frame_info *this_frame, void **this_cache)
+{
+ struct moxie_frame_cache *cache;
+ CORE_ADDR current_pc;
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = moxie_alloc_frame_cache ();
+ *this_cache = cache;
+
+ cache->base = get_frame_register_unsigned (this_frame, MOXIE_FP_REGNUM);
+ if (cache->base == 0)
+ return cache;
+
+ cache->pc = get_frame_func (this_frame);
+ current_pc = get_frame_pc (this_frame);
+ if (cache->pc)
+ moxie_analyze_prologue (cache->pc, current_pc, cache, this_frame);
+
+ cache->saved_sp = cache->base - cache->framesize;
+
+ for (i = 0; i < MOXIE_NUM_REGS; ++i)
+ if (cache->saved_regs[i] != REG_UNAVAIL)
+ cache->saved_regs[i] = cache->base - cache->saved_regs[i];
+
+ return cache;
+}
+
+/* Implement the "unwind_pc" gdbarch method. */
+
+static CORE_ADDR
+moxie_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, MOXIE_PC_REGNUM);
+}
+
+/* Given a GDB frame, determine the address of the calling function's
+ frame. This will be used to create a new GDB frame struct. */
+
+static void
+moxie_frame_this_id (struct frame_info *this_frame,
+ void **this_prologue_cache, struct frame_id *this_id)
+{
+ struct moxie_frame_cache *cache = moxie_frame_cache (this_frame,
+ this_prologue_cache);
+
+ /* This marks the outermost frame. */
+ if (cache->base == 0)
+ return;
+
+ *this_id = frame_id_build (cache->saved_sp, cache->pc);
+}
+
+/* Get the value of register regnum in the previous stack frame. */
+
+static struct value *
+moxie_frame_prev_register (struct frame_info *this_frame,
+ void **this_prologue_cache, int regnum)
+{
+ struct moxie_frame_cache *cache = moxie_frame_cache (this_frame,
+ this_prologue_cache);
+
+ gdb_assert (regnum >= 0);
+
+ if (regnum == MOXIE_SP_REGNUM && cache->saved_sp)
+ return frame_unwind_got_constant (this_frame, regnum, cache->saved_sp);
+
+ if (regnum < MOXIE_NUM_REGS && cache->saved_regs[regnum] != REG_UNAVAIL)
+ return frame_unwind_got_memory (this_frame, regnum,
+ cache->saved_regs[regnum]);
+
+ return frame_unwind_got_register (this_frame, regnum, regnum);
+}
+
+static const struct frame_unwind moxie_frame_unwind = {
+ NORMAL_FRAME,
+ moxie_frame_this_id,
+ moxie_frame_prev_register,
+ NULL,
+ default_frame_sniffer
+};
+
+/* Return the base address of this_frame. */
+
+static CORE_ADDR
+moxie_frame_base_address (struct frame_info *this_frame, void **this_cache)
+{
+ struct moxie_frame_cache *cache = moxie_frame_cache (this_frame,
+ this_cache);
+
+ return cache->base;
+}
+
+static const struct frame_base moxie_frame_base = {
+ &moxie_frame_unwind,
+ moxie_frame_base_address,
+ moxie_frame_base_address,
+ moxie_frame_base_address
+};
+
+static struct frame_id
+moxie_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+ CORE_ADDR sp = get_frame_register_unsigned (this_frame, MOXIE_SP_REGNUM);
+
+ return frame_id_build (sp, get_frame_pc (this_frame));
+}
+
+/* Allocate and initialize the moxie gdbarch object. */
+
+static struct gdbarch *
+moxie_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+ struct gdbarch *gdbarch;
+ struct gdbarch_tdep *tdep;
+
+ /* If there is already a candidate, use it. */
+ arches = gdbarch_list_lookup_by_info (arches, &info);
+ if (arches != NULL)
+ return arches->gdbarch;
+
+ /* Allocate space for the new architecture. */
+ tdep = XMALLOC (struct gdbarch_tdep);
+ gdbarch = gdbarch_alloc (&info, tdep);
+
+ set_gdbarch_read_pc (gdbarch, moxie_read_pc);
+ set_gdbarch_write_pc (gdbarch, moxie_write_pc);
+ set_gdbarch_unwind_sp (gdbarch, moxie_unwind_sp);
+
+ set_gdbarch_num_regs (gdbarch, MOXIE_NUM_REGS);
+ set_gdbarch_sp_regnum (gdbarch, MOXIE_SP_REGNUM);
+ set_gdbarch_register_name (gdbarch, moxie_register_name);
+ set_gdbarch_register_type (gdbarch, moxie_register_type);
+
+ set_gdbarch_return_value (gdbarch, moxie_return_value);
+
+ set_gdbarch_skip_prologue (gdbarch, moxie_skip_prologue);
+ set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+ set_gdbarch_breakpoint_from_pc (gdbarch, moxie_breakpoint_from_pc);
+ set_gdbarch_frame_align (gdbarch, moxie_frame_align);
+
+ frame_base_set_default (gdbarch, &moxie_frame_base);
+
+ /* Methods for saving / extracting a dummy frame's ID. The ID's
+ stack address must match the SP value returned by
+ PUSH_DUMMY_CALL, and saved by generic_save_dummy_frame_tos. */
+ set_gdbarch_dummy_id (gdbarch, moxie_dummy_id);
+
+ set_gdbarch_unwind_pc (gdbarch, moxie_unwind_pc);
+
+ set_gdbarch_print_insn (gdbarch, print_insn_moxie);
+
+ /* Hook in ABI-specific overrides, if they have been registered. */
+ gdbarch_init_osabi (info, gdbarch);
+
+ /* Hook in the default unwinders. */
+ frame_unwind_append_unwinder (gdbarch, &moxie_frame_unwind);
+
+ /* Support simple overlay manager. */
+ set_gdbarch_overlay_update (gdbarch, simple_overlay_update);
+
+ return gdbarch;
+}
+
+/* Register this machine's init routine. */
+
+void
+_initialize_moxie_tdep (void)
+{
+ register_gdbarch_init (bfd_arch_moxie, moxie_gdbarch_init);
+}
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