gdb: ft32: new port

FT32 is a new high performance 32-bit RISC core developed by FTDI for
embedded applications.

1 files changed, 549 insertions, 0 deletions

diff --git a/gdb/ft32-tdep.c b/gdb/ft32-tdep.c
new file mode 100644
index 0000000..41a7191
--- /dev/null
+++ b/gdb/ft32-tdep.c
@@ -0,0 +1,549 @@
+/* Target-dependent code for FT32.
+
+   Copyright (C) 2009-2015 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 "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 "record.h"
+
+#include "gdb_assert.h"
+
+#include "ft32-tdep.h"
+#include "gdb/sim-ft32.h"
+
+#define RAM_BIAS  0x800000  /* Bias added to RAM addresses.  */
+
+/* Local functions.  */
+
+extern void _initialize_ft32_tdep (void);
+
+/* Use an invalid address -1 as 'not available' marker.  */
+enum { REG_UNAVAIL = (CORE_ADDR) (-1) };
+
+struct ft32_frame_cache
+{
+  /* Base address of the frame */
+  CORE_ADDR base;
+  /* Function this frame belongs to */
+  CORE_ADDR pc;
+  /* Total size of this frame */
+  LONGEST framesize;
+  /* Saved registers in this frame */
+  CORE_ADDR saved_regs[FT32_NUM_REGS];
+  /* Saved SP in this frame */
+  CORE_ADDR saved_sp;
+  /* Has the new frame been LINKed.  */
+  bfd_boolean established;
+};
+
+/* Implement the "frame_align" gdbarch method.  */
+
+static CORE_ADDR
+ft32_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.  */
+
+static const unsigned char *
+ft32_breakpoint_from_pc (struct gdbarch *gdbarch,
+			 CORE_ADDR *pcptr, int *lenptr)
+{
+  static const gdb_byte breakpoint[] = { 0x02, 0x00, 0x34, 0x00 };
+
+  *lenptr = sizeof (breakpoint);
+  return breakpoint;
+}
+
+/* FT32 register names.  */
+
+static const char *const ft32_register_names[] =
+{
+    "fp", "sp",
+    "r0", "r1", "r2", "r3",  "r4", "r5", "r6", "r7",
+    "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
+    "r16", "r17", "r18", "r19",  "r20", "r21", "r22", "r23",
+    "r24", "r25", "r26", "r27", "r28", "cc",
+    "pc"
+};
+
+/* Implement the "register_name" gdbarch method.  */
+
+static const char *
+ft32_register_name (struct gdbarch *gdbarch, int reg_nr)
+{
+  if (reg_nr < 0)
+    return NULL;
+  if (reg_nr >= FT32_NUM_REGS)
+    return NULL;
+  return ft32_register_names[reg_nr];
+}
+
+/* Implement the "register_type" gdbarch method.  */
+
+static struct type *
+ft32_register_type (struct gdbarch *gdbarch, int reg_nr)
+{
+  if (reg_nr == FT32_PC_REGNUM)
+    return builtin_type (gdbarch)->builtin_func_ptr;
+  else if (reg_nr == FT32_SP_REGNUM || reg_nr == FT32_FP_REGNUM)
+    return builtin_type (gdbarch)->builtin_data_ptr;
+  else
+    return builtin_type (gdbarch)->builtin_int32;
+}
+
+/* Write into appropriate registers a function return value
+   of type TYPE, given in virtual format.  */
+
+static void
+ft32_store_return_value (struct type *type, struct regcache *regcache,
+			 const gdb_byte *valbuf)
+{
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  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, byte_order);
+  regcache_cooked_write_unsigned (regcache, FT32_R0_REGNUM, regval);
+  if (len > 4)
+    {
+      regval = extract_unsigned_integer (valbuf + 4,
+					 len - 4, byte_order);
+      regcache_cooked_write_unsigned (regcache, FT32_R1_REGNUM, 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.  */
+
+#define IS_PUSH(inst)   (((inst) & 0xfff00000) == 0x84000000)
+#define PUSH_REG(inst)  (FT32_R0_REGNUM + (((inst) >> 15) & 0x1f))
+#define IS_LINK(inst)   (((inst) & 0xffff0000) == 0x95d00000)
+#define LINK_SIZE(inst) ((inst) & 0xffff)
+
+static CORE_ADDR
+ft32_analyze_prologue (CORE_ADDR start_addr, CORE_ADDR end_addr,
+		       struct ft32_frame_cache *cache,
+		       struct gdbarch *gdbarch)
+{
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  CORE_ADDR next_addr;
+  ULONGEST inst, inst2;
+  LONGEST offset;
+  int regnum;
+
+  cache->saved_regs[FT32_PC_REGNUM] = 0;
+  cache->framesize = 0;
+
+  if (start_addr >= end_addr)
+      return end_addr;
+
+  cache->established = 0;
+  for (next_addr = start_addr; next_addr < end_addr; )
+    {
+      inst = read_memory_unsigned_integer (next_addr, 4, byte_order);
+
+      if (IS_PUSH (inst))
+	{
+	  regnum = PUSH_REG (inst);
+	  cache->framesize += 4;
+	  cache->saved_regs[regnum] = cache->framesize;
+	  next_addr += 4;
+	}
+      else
+	break;
+    }
+  for (regnum = FT32_R0_REGNUM; regnum < FT32_PC_REGNUM; regnum++)
+    {
+      if (cache->saved_regs[regnum] != REG_UNAVAIL)
+	cache->saved_regs[regnum] = cache->framesize - cache->saved_regs[regnum];
+    }
+  cache->saved_regs[FT32_PC_REGNUM] = cache->framesize;
+
+  /* It is a LINK?  */
+  if (next_addr < end_addr)
+    {
+      inst = read_memory_unsigned_integer (next_addr, 4, byte_order);
+      if (IS_LINK (inst))
+	{
+	  cache->established = 1;
+	  for (regnum = FT32_R0_REGNUM; regnum < FT32_PC_REGNUM; regnum++)
+	    {
+	      if (cache->saved_regs[regnum] != REG_UNAVAIL)
+		cache->saved_regs[regnum] += 4;
+	    }
+	  cache->saved_regs[FT32_PC_REGNUM] = cache->framesize + 4;
+	  cache->saved_regs[FT32_FP_REGNUM] = 0;
+	  cache->framesize += LINK_SIZE (inst);
+	  next_addr += 4;
+	}
+    }
+
+  return next_addr;
+}
+
+/* Find the end of function prologue.  */
+
+static CORE_ADDR
+ft32_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+  CORE_ADDR func_addr = 0, func_end = 0;
+  const 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 (gdbarch, 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 ft32_frame_cache cache;
+	  CORE_ADDR plg_end;
+
+	  memset (&cache, 0, sizeof cache);
+
+	  plg_end = ft32_analyze_prologue (func_addr,
+					   func_end, &cache, gdbarch);
+	  /* 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 != NULL) && 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 pc;
+}
+
+/* Implement the "read_pc" gdbarch method.  */
+
+static CORE_ADDR
+ft32_read_pc (struct regcache *regcache)
+{
+  ULONGEST pc;
+
+  regcache_cooked_read_unsigned (regcache, FT32_PC_REGNUM, &pc);
+  return pc;
+}
+
+/* Implement the "write_pc" gdbarch method.  */
+
+static void
+ft32_write_pc (struct regcache *regcache, CORE_ADDR val)
+{
+  regcache_cooked_write_unsigned (regcache, FT32_PC_REGNUM, val);
+}
+
+/* Implement the "unwind_sp" gdbarch method.  */
+
+static CORE_ADDR
+ft32_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+  return frame_unwind_register_unsigned (next_frame, FT32_SP_REGNUM);
+}
+
+/* Given a return value in `regbuf' with a type `valtype',
+   extract and copy its value into `valbuf'.  */
+
+static void
+ft32_extract_return_value (struct type *type, struct regcache *regcache,
+			   gdb_byte *dst)
+{
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  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, FT32_R0_REGNUM, &tmp);
+  store_unsigned_integer (valbuf, (len > 4 ? len - 4 : len), byte_order, tmp);
+
+  /* Ignore return values more than 8 bytes in size because the ft32
+     returns anything more than 8 bytes in the stack.  */
+  if (len > 4)
+    {
+      regcache_cooked_read_unsigned (regcache, FT32_R1_REGNUM, &tmp);
+      store_unsigned_integer (valbuf + len - 4, 4, byte_order, tmp);
+    }
+}
+
+/* Implement the "return_value" gdbarch method.  */
+
+static enum return_value_convention
+ft32_return_value (struct gdbarch *gdbarch, struct value *function,
+		   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)
+	ft32_extract_return_value (valtype, regcache, readbuf);
+      if (writebuf != NULL)
+	ft32_store_return_value (valtype, regcache, writebuf);
+      return RETURN_VALUE_REGISTER_CONVENTION;
+    }
+}
+
+/* Allocate and initialize a ft32_frame_cache object.  */
+
+static struct ft32_frame_cache *
+ft32_alloc_frame_cache (void)
+{
+  struct ft32_frame_cache *cache;
+  int i;
+
+  cache = FRAME_OBSTACK_ZALLOC (struct ft32_frame_cache);
+
+  for (i = 0; i < FT32_NUM_REGS; ++i)
+    cache->saved_regs[i] = REG_UNAVAIL;
+
+  return cache;
+}
+
+/* Populate a ft32_frame_cache object for this_frame.  */
+
+static struct ft32_frame_cache *
+ft32_frame_cache (struct frame_info *this_frame, void **this_cache)
+{
+  struct ft32_frame_cache *cache;
+  CORE_ADDR current_pc;
+  int i;
+
+  if (*this_cache)
+    return *this_cache;
+
+  cache = ft32_alloc_frame_cache ();
+  *this_cache = cache;
+
+  cache->base = get_frame_register_unsigned (this_frame, FT32_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)
+    {
+      struct gdbarch *gdbarch = get_frame_arch (this_frame);
+
+      ft32_analyze_prologue (cache->pc, current_pc, cache, gdbarch);
+      if (!cache->established)
+	cache->base = get_frame_register_unsigned (this_frame, FT32_SP_REGNUM);
+    }
+
+  cache->saved_sp = cache->base - 4;
+
+  for (i = 0; i < FT32_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
+ft32_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+  return frame_unwind_register_unsigned (next_frame, FT32_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
+ft32_frame_this_id (struct frame_info *this_frame,
+		    void **this_prologue_cache, struct frame_id *this_id)
+{
+  struct ft32_frame_cache *cache = ft32_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 *
+ft32_frame_prev_register (struct frame_info *this_frame,
+			  void **this_prologue_cache, int regnum)
+{
+  struct ft32_frame_cache *cache = ft32_frame_cache (this_frame,
+						     this_prologue_cache);
+
+  gdb_assert (regnum >= 0);
+
+  if (regnum == FT32_SP_REGNUM && cache->saved_sp)
+    return frame_unwind_got_constant (this_frame, regnum, cache->saved_sp);
+
+  if (regnum < FT32_NUM_REGS && cache->saved_regs[regnum] != REG_UNAVAIL)
+      return frame_unwind_got_memory (this_frame, regnum,
+				      RAM_BIAS | cache->saved_regs[regnum]);
+
+  return frame_unwind_got_register (this_frame, regnum, regnum);
+}
+
+static const struct frame_unwind ft32_frame_unwind =
+{
+  NORMAL_FRAME,
+  default_frame_unwind_stop_reason,
+  ft32_frame_this_id,
+  ft32_frame_prev_register,
+  NULL,
+  default_frame_sniffer
+};
+
+/* Return the base address of this_frame.  */
+
+static CORE_ADDR
+ft32_frame_base_address (struct frame_info *this_frame, void **this_cache)
+{
+  struct ft32_frame_cache *cache = ft32_frame_cache (this_frame,
+						     this_cache);
+
+  return cache->base;
+}
+
+static const struct frame_base ft32_frame_base =
+{
+  &ft32_frame_unwind,
+  ft32_frame_base_address,
+  ft32_frame_base_address,
+  ft32_frame_base_address
+};
+
+static struct frame_id
+ft32_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
+{
+  CORE_ADDR sp = get_frame_register_unsigned (this_frame, FT32_SP_REGNUM);
+
+  return frame_id_build (sp, get_frame_pc (this_frame));
+}
+
+/* Allocate and initialize the ft32 gdbarch object.  */
+
+static struct gdbarch *
+ft32_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 = XNEW (struct gdbarch_tdep);
+  gdbarch = gdbarch_alloc (&info, tdep);
+
+  set_gdbarch_read_pc (gdbarch, ft32_read_pc);
+  set_gdbarch_write_pc (gdbarch, ft32_write_pc);
+  set_gdbarch_unwind_sp (gdbarch, ft32_unwind_sp);
+
+  set_gdbarch_num_regs (gdbarch, FT32_NUM_REGS);
+  set_gdbarch_sp_regnum (gdbarch, FT32_SP_REGNUM);
+  set_gdbarch_pc_regnum (gdbarch, FT32_PC_REGNUM);
+  set_gdbarch_register_name (gdbarch, ft32_register_name);
+  set_gdbarch_register_type (gdbarch, ft32_register_type);
+
+  set_gdbarch_return_value (gdbarch, ft32_return_value);
+
+  set_gdbarch_skip_prologue (gdbarch, ft32_skip_prologue);
+  set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+  set_gdbarch_breakpoint_from_pc (gdbarch, ft32_breakpoint_from_pc);
+  set_gdbarch_frame_align (gdbarch, ft32_frame_align);
+
+  frame_base_set_default (gdbarch, &ft32_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, ft32_dummy_id);
+
+  set_gdbarch_unwind_pc (gdbarch, ft32_unwind_pc);
+
+  set_gdbarch_print_insn (gdbarch, print_insn_ft32);
+
+  /* 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, &ft32_frame_unwind);
+
+  /* Support simple overlay manager.  */
+  set_gdbarch_overlay_update (gdbarch, simple_overlay_update);
+
+  return gdbarch;
+}
+
+/* Register this machine's init routine.  */
+
+void
+_initialize_ft32_tdep (void)
+{
+  register_gdbarch_init (bfd_arch_ft32, ft32_gdbarch_init);
+}