/* Common target dependent code for GDB on ARM systems.
Copyright (C) 1988, 1989, 1991, 1992, 1993, 1995, 1996, 1998, 1999, 2000,
- 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
This file is part of GDB.
#include "elf/arm.h"
#include "gdb_assert.h"
+#include "vec.h"
static int arm_debug;
MSYMBOL_IS_SPECIAL Tests the "special" bit in a minimal symbol. */
#define MSYMBOL_SET_SPECIAL(msym) \
- MSYMBOL_INFO (msym) = (char *) (((long) MSYMBOL_INFO (msym)) \
- | 0x80000000)
+ MSYMBOL_TARGET_FLAG_1 (msym) = 1
#define MSYMBOL_IS_SPECIAL(msym) \
- (((long) MSYMBOL_INFO (msym) & 0x80000000) != 0)
+ MSYMBOL_TARGET_FLAG_1 (msym)
+
+/* Per-objfile data used for mapping symbols. */
+static const struct objfile_data *arm_objfile_data_key;
+
+struct arm_mapping_symbol
+{
+ bfd_vma value;
+ char type;
+};
+typedef struct arm_mapping_symbol arm_mapping_symbol_s;
+DEF_VEC_O(arm_mapping_symbol_s);
+
+struct arm_per_objfile
+{
+ VEC(arm_mapping_symbol_s) **section_maps;
+};
/* The list of available "set arm ..." and "show arm ..." commands. */
static struct cmd_list_element *setarmcmdlist = NULL;
static enum arm_abi_kind arm_abi_global = ARM_ABI_AUTO;
static const char *arm_abi_string = "auto";
+/* The execution mode to assume. */
+static const char *arm_mode_strings[] =
+ {
+ "auto",
+ "arm",
+ "thumb"
+ };
+
+static const char *arm_fallback_mode_string = "auto";
+static const char *arm_force_mode_string = "auto";
+
/* Number of different reg name sets (options). */
static int num_disassembly_options;
static void convert_to_extended (const struct floatformat *, void *,
const void *, int);
+static void arm_neon_quad_read (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int regnum, gdb_byte *buf);
+static void arm_neon_quad_write (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int regnum, const gdb_byte *buf);
+
struct arm_prologue_cache
{
/* The stack pointer at the time this frame was created; i.e. the
struct trad_frame_saved_reg *saved_regs;
};
+/* Architecture version for displaced stepping. This effects the behaviour of
+ certain instructions, and really should not be hard-wired. */
+
+#define DISPLACED_STEPPING_ARCH_VERSION 5
+
/* Addresses for calling Thumb functions have the bit 0 set.
Here are some macros to test, set, or clear bit 0 of addresses. */
#define IS_THUMB_ADDR(addr) ((addr) & 1)
return (cpsr & CPSR_T) != 0;
}
+/* Callback for VEC_lower_bound. */
+
+static inline int
+arm_compare_mapping_symbols (const struct arm_mapping_symbol *lhs,
+ const struct arm_mapping_symbol *rhs)
+{
+ return lhs->value < rhs->value;
+}
+
/* Determine if the program counter specified in MEMADDR is in a Thumb
function. This function should be called for addresses unrelated to
any executing frame; otherwise, prefer arm_frame_is_thumb. */
static int
arm_pc_is_thumb (CORE_ADDR memaddr)
{
+ struct obj_section *sec;
struct minimal_symbol *sym;
/* If bit 0 of the address is set, assume this is a Thumb address. */
if (IS_THUMB_ADDR (memaddr))
return 1;
+ /* If the user wants to override the symbol table, let him. */
+ if (strcmp (arm_force_mode_string, "arm") == 0)
+ return 0;
+ if (strcmp (arm_force_mode_string, "thumb") == 0)
+ return 1;
+
+ /* If there are mapping symbols, consult them. */
+ sec = find_pc_section (memaddr);
+ if (sec != NULL)
+ {
+ struct arm_per_objfile *data;
+ VEC(arm_mapping_symbol_s) *map;
+ struct arm_mapping_symbol map_key = { memaddr - obj_section_addr (sec),
+ 0 };
+ unsigned int idx;
+
+ data = objfile_data (sec->objfile, arm_objfile_data_key);
+ if (data != NULL)
+ {
+ map = data->section_maps[sec->the_bfd_section->index];
+ if (!VEC_empty (arm_mapping_symbol_s, map))
+ {
+ struct arm_mapping_symbol *map_sym;
+
+ idx = VEC_lower_bound (arm_mapping_symbol_s, map, &map_key,
+ arm_compare_mapping_symbols);
+
+ /* VEC_lower_bound finds the earliest ordered insertion
+ point. If the following symbol starts at this exact
+ address, we use that; otherwise, the preceding
+ mapping symbol covers this address. */
+ if (idx < VEC_length (arm_mapping_symbol_s, map))
+ {
+ map_sym = VEC_index (arm_mapping_symbol_s, map, idx);
+ if (map_sym->value == map_key.value)
+ return map_sym->type == 't';
+ }
+
+ if (idx > 0)
+ {
+ map_sym = VEC_index (arm_mapping_symbol_s, map, idx - 1);
+ return map_sym->type == 't';
+ }
+ }
+ }
+ }
+
/* Thumb functions have a "special" bit set in minimal symbols. */
sym = lookup_minimal_symbol_by_pc (memaddr);
if (sym)
- {
- return (MSYMBOL_IS_SPECIAL (sym));
- }
- else
- {
- return 0;
- }
+ return (MSYMBOL_IS_SPECIAL (sym));
+
+ /* If the user wants to override the fallback mode, let them. */
+ if (strcmp (arm_fallback_mode_string, "arm") == 0)
+ return 0;
+ if (strcmp (arm_fallback_mode_string, "thumb") == 0)
+ return 1;
+
+ /* If we couldn't find any symbol, but we're talking to a running
+ target, then trust the current value of $cpsr. This lets
+ "display/i $pc" always show the correct mode (though if there is
+ a symbol table we will not reach here, so it still may not be
+ displayed in the mode it will be executed). */
+ if (target_has_registers)
+ return arm_frame_is_thumb (get_current_frame ());
+
+ /* Otherwise we're out of luck; we assume ARM. */
+ return 0;
}
/* Remove useless bits from addresses in a running program. */
static CORE_ADDR
-arm_addr_bits_remove (CORE_ADDR val)
+arm_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR val)
{
if (arm_apcs_32)
return UNMAKE_THUMB_ADDR (val);
/* When reading symbols, we need to zap the low bit of the address,
which may be set to 1 for Thumb functions. */
static CORE_ADDR
-arm_smash_text_address (CORE_ADDR val)
+arm_smash_text_address (struct gdbarch *gdbarch, CORE_ADDR val)
{
return val & ~1;
}
CORE_ADDR start, CORE_ADDR limit,
struct arm_prologue_cache *cache)
{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
int i;
pv_t regs[16];
struct pv_area *stack;
for (i = 0; i < 16; i++)
regs[i] = pv_register (i, 0);
- stack = make_pv_area (ARM_SP_REGNUM);
+ stack = make_pv_area (ARM_SP_REGNUM, gdbarch_addr_bit (gdbarch));
back_to = make_cleanup_free_pv_area (stack);
while (start < limit)
{
unsigned short insn;
- insn = read_memory_unsigned_integer (start, 2);
+ insn = read_memory_unsigned_integer (start, 2, byte_order_for_code);
if ((insn & 0xfe00) == 0xb400) /* push { rlist } */
{
static CORE_ADDR
arm_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
{
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
unsigned long inst;
CORE_ADDR skip_pc;
- CORE_ADDR func_addr, func_end = 0;
- char *func_name;
+ CORE_ADDR func_addr, limit_pc;
struct symtab_and_line sal;
/* If we're in a dummy frame, don't even try to skip the prologue. */
- if (deprecated_pc_in_call_dummy (pc))
+ if (deprecated_pc_in_call_dummy (gdbarch, pc))
return pc;
- /* See what the symbol table says. */
-
- if (find_pc_partial_function (pc, &func_name, &func_addr, &func_end))
+ /* 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, NULL, &func_addr, NULL))
{
- struct symbol *sym;
-
- /* Found a function. */
- sym = lookup_symbol (func_name, NULL, VAR_DOMAIN, NULL, NULL);
- if (sym && SYMBOL_LANGUAGE (sym) != language_asm)
- {
- /* Don't use this trick for assembly source files. */
- sal = find_pc_line (func_addr, 0);
- if ((sal.line != 0) && (sal.end < func_end))
- return sal.end;
- }
+ CORE_ADDR post_prologue_pc
+ = skip_prologue_using_sal (gdbarch, func_addr);
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
}
- /* Can't find the prologue end in the symbol table, try it the hard way
- by disassembling the instructions. */
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
+ /* Find an upper limit on the function prologue using the debug
+ information. If the debug information could not be used to provide
+ that bound, then use an arbitrary large number as the upper bound. */
/* Like arm_scan_prologue, stop no later than pc + 64. */
- if (func_end == 0 || func_end > pc + 64)
- func_end = pc + 64;
+ limit_pc = skip_prologue_using_sal (gdbarch, pc);
+ if (limit_pc == 0)
+ limit_pc = pc + 64; /* Magic. */
+
/* Check if this is Thumb code. */
if (arm_pc_is_thumb (pc))
- return thumb_analyze_prologue (gdbarch, pc, func_end, NULL);
+ return thumb_analyze_prologue (gdbarch, pc, limit_pc, NULL);
- for (skip_pc = pc; skip_pc < func_end; skip_pc += 4)
+ for (skip_pc = pc; skip_pc < limit_pc; skip_pc += 4)
{
- inst = read_memory_unsigned_integer (skip_pc, 4);
+ inst = read_memory_unsigned_integer (skip_pc, 4, byte_order_for_code);
/* "mov ip, sp" is no longer a required part of the prologue. */
if (inst == 0xe1a0c00d) /* mov ip, sp */
if ((inst & 0xfffff000) == 0xe24dd000) /* sub sp, sp, #nn */
continue;
- if ((inst & 0xffffc000) == 0xe54b0000 || /* strb r(0123),[r11,#-nn] */
- (inst & 0xffffc0f0) == 0xe14b00b0 || /* strh r(0123),[r11,#-nn] */
- (inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */
+ if ((inst & 0xffffc000) == 0xe54b0000 /* strb r(0123),[r11,#-nn] */
+ || (inst & 0xffffc0f0) == 0xe14b00b0 /* strh r(0123),[r11,#-nn] */
+ || (inst & 0xffffc000) == 0xe50b0000) /* str r(0123),[r11,#-nn] */
continue;
- if ((inst & 0xffffc000) == 0xe5cd0000 || /* strb r(0123),[sp,#nn] */
- (inst & 0xffffc0f0) == 0xe1cd00b0 || /* strh r(0123),[sp,#nn] */
- (inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */
+ if ((inst & 0xffffc000) == 0xe5cd0000 /* strb r(0123),[sp,#nn] */
+ || (inst & 0xffffc0f0) == 0xe1cd00b0 /* strh r(0123),[sp,#nn] */
+ || (inst & 0xffffc000) == 0xe58d0000) /* str r(0123),[sp,#nn] */
continue;
/* Un-recognized instruction; stop scanning. */
struct arm_prologue_cache *cache)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
int regno;
CORE_ADDR prologue_start, prologue_end, current_pc;
CORE_ADDR prev_pc = get_frame_pc (this_frame);
LONGEST return_value;
frame_loc = get_frame_register_unsigned (this_frame, ARM_FP_REGNUM);
- if (!safe_read_memory_integer (frame_loc, 4, &return_value))
+ if (!safe_read_memory_integer (frame_loc, 4, byte_order, &return_value))
return;
else
{
for (regno = 0; regno < ARM_FPS_REGNUM; regno++)
regs[regno] = pv_register (regno, 0);
- stack = make_pv_area (ARM_SP_REGNUM);
+ stack = make_pv_area (ARM_SP_REGNUM, gdbarch_addr_bit (gdbarch));
back_to = make_cleanup_free_pv_area (stack);
for (current_pc = prologue_start;
current_pc < prologue_end;
current_pc += 4)
{
- unsigned int insn = read_memory_unsigned_integer (current_pc, 4);
+ unsigned int insn
+ = read_memory_unsigned_integer (current_pc, 4, byte_order_for_code);
if (insn == 0xe1a0c00d) /* mov ip, sp */
{
pv_area_store (stack, regs[ARM_SP_REGNUM], 4, regs[regno]);
}
}
- else if ((insn & 0xffffc000) == 0xe54b0000 || /* strb rx,[r11,#-n] */
- (insn & 0xffffc0f0) == 0xe14b00b0 || /* strh rx,[r11,#-n] */
- (insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */
+ else if ((insn & 0xffffc000) == 0xe54b0000 /* strb rx,[r11,#-n] */
+ || (insn & 0xffffc0f0) == 0xe14b00b0 /* strh rx,[r11,#-n] */
+ || (insn & 0xffffc000) == 0xe50b0000) /* str rx,[r11,#-n] */
{
/* No need to add this to saved_regs -- it's just an arg reg. */
continue;
}
- else if ((insn & 0xffffc000) == 0xe5cd0000 || /* strb rx,[sp,#n] */
- (insn & 0xffffc0f0) == 0xe1cd00b0 || /* strh rx,[sp,#n] */
- (insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */
+ else if ((insn & 0xffffc000) == 0xe5cd0000 /* strb rx,[sp,#n] */
+ || (insn & 0xffffc0f0) == 0xe1cd00b0 /* strh rx,[sp,#n] */
+ || (insn & 0xffffc000) == 0xe58d0000) /* str rx,[sp,#n] */
{
/* No need to add this to saved_regs -- it's just an arg reg. */
continue;
{
struct arm_prologue_cache *cache;
struct frame_id id;
- CORE_ADDR func;
+ CORE_ADDR pc, func;
if (*this_cache == NULL)
*this_cache = arm_make_prologue_cache (this_frame);
cache = *this_cache;
- func = get_frame_func (this_frame);
-
- /* This is meant to halt the backtrace at "_start". Make sure we
- don't halt it at a generic dummy frame. */
- if (func <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc)
+ /* This is meant to halt the backtrace at "_start". */
+ pc = get_frame_pc (this_frame);
+ if (pc <= gdbarch_tdep (get_frame_arch (this_frame))->lowest_pc)
return;
/* If we've hit a wall, stop. */
if (cache->prev_sp == 0)
return;
+ func = get_frame_func (this_frame);
id = frame_id_build (cache->prev_sp, func);
*this_id = id;
}
void **this_cache,
int prev_regnum)
{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct arm_prologue_cache *cache;
if (*this_cache == NULL)
lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
return frame_unwind_got_constant (this_frame, prev_regnum,
- arm_addr_bits_remove (lr));
+ arm_addr_bits_remove (gdbarch, lr));
}
/* SP is generally not saved to the stack, but this frame is
{
CORE_ADDR pc;
pc = frame_unwind_register_unsigned (this_frame, ARM_PC_REGNUM);
- return arm_addr_bits_remove (pc);
+ return arm_addr_bits_remove (gdbarch, pc);
}
static CORE_ADDR
arm_dwarf2_prev_register (struct frame_info *this_frame, void **this_cache,
int regnum)
{
+ struct gdbarch * gdbarch = get_frame_arch (this_frame);
CORE_ADDR lr, cpsr;
switch (regnum)
part of the PC. */
lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
return frame_unwind_got_constant (this_frame, regnum,
- arm_addr_bits_remove (lr));
+ arm_addr_bits_remove (gdbarch, lr));
case ARM_PS_REGNUM:
/* Reconstruct the T bit; see arm_prologue_prev_register for details. */
- CORE_ADDR lr, cpsr;
-
- cpsr = get_frame_register_unsigned (this_frame, prev_regnum);
+ cpsr = get_frame_register_unsigned (this_frame, regnum);
lr = frame_unwind_register_unsigned (this_frame, ARM_LR_REGNUM);
if (IS_THUMB_ADDR (lr))
cpsr |= CPSR_T;
else
cpsr &= ~CPSR_T;
- return frame_unwind_got_constant (this_frame, prev_regnum, cpsr);
+ return frame_unwind_got_constant (this_frame, regnum, cpsr);
default:
internal_error (__FILE__, __LINE__,
}
}
-/* We currently only support passing parameters in integer registers. This
- conforms with GCC's default model. Several other variants exist and
+/* Possible base types for a candidate for passing and returning in
+ VFP registers. */
+
+enum arm_vfp_cprc_base_type
+{
+ VFP_CPRC_UNKNOWN,
+ VFP_CPRC_SINGLE,
+ VFP_CPRC_DOUBLE,
+ VFP_CPRC_VEC64,
+ VFP_CPRC_VEC128
+};
+
+/* The length of one element of base type B. */
+
+static unsigned
+arm_vfp_cprc_unit_length (enum arm_vfp_cprc_base_type b)
+{
+ switch (b)
+ {
+ case VFP_CPRC_SINGLE:
+ return 4;
+ case VFP_CPRC_DOUBLE:
+ return 8;
+ case VFP_CPRC_VEC64:
+ return 8;
+ case VFP_CPRC_VEC128:
+ return 16;
+ default:
+ internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
+ (int) b);
+ }
+}
+
+/* The character ('s', 'd' or 'q') for the type of VFP register used
+ for passing base type B. */
+
+static int
+arm_vfp_cprc_reg_char (enum arm_vfp_cprc_base_type b)
+{
+ switch (b)
+ {
+ case VFP_CPRC_SINGLE:
+ return 's';
+ case VFP_CPRC_DOUBLE:
+ return 'd';
+ case VFP_CPRC_VEC64:
+ return 'd';
+ case VFP_CPRC_VEC128:
+ return 'q';
+ default:
+ internal_error (__FILE__, __LINE__, _("Invalid VFP CPRC type: %d."),
+ (int) b);
+ }
+}
+
+/* Determine whether T may be part of a candidate for passing and
+ returning in VFP registers, ignoring the limit on the total number
+ of components. If *BASE_TYPE is VFP_CPRC_UNKNOWN, set it to the
+ classification of the first valid component found; if it is not
+ VFP_CPRC_UNKNOWN, all components must have the same classification
+ as *BASE_TYPE. If it is found that T contains a type not permitted
+ for passing and returning in VFP registers, a type differently
+ classified from *BASE_TYPE, or two types differently classified
+ from each other, return -1, otherwise return the total number of
+ base-type elements found (possibly 0 in an empty structure or
+ array). Vectors and complex types are not currently supported,
+ matching the generic AAPCS support. */
+
+static int
+arm_vfp_cprc_sub_candidate (struct type *t,
+ enum arm_vfp_cprc_base_type *base_type)
+{
+ t = check_typedef (t);
+ switch (TYPE_CODE (t))
+ {
+ case TYPE_CODE_FLT:
+ switch (TYPE_LENGTH (t))
+ {
+ case 4:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_SINGLE;
+ else if (*base_type != VFP_CPRC_SINGLE)
+ return -1;
+ return 1;
+
+ case 8:
+ if (*base_type == VFP_CPRC_UNKNOWN)
+ *base_type = VFP_CPRC_DOUBLE;
+ else if (*base_type != VFP_CPRC_DOUBLE)
+ return -1;
+ return 1;
+
+ default:
+ return -1;
+ }
+ break;
+
+ case TYPE_CODE_ARRAY:
+ {
+ int count;
+ unsigned unitlen;
+ count = arm_vfp_cprc_sub_candidate (TYPE_TARGET_TYPE (t), base_type);
+ if (count == -1)
+ return -1;
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ gdb_assert ((TYPE_LENGTH (t) % unitlen) == 0);
+ return TYPE_LENGTH (t) / unitlen;
+ }
+ break;
+
+ case TYPE_CODE_STRUCT:
+ {
+ int count = 0;
+ unsigned unitlen;
+ int i;
+ for (i = 0; i < TYPE_NFIELDS (t); i++)
+ {
+ int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
+ base_type);
+ if (sub_count == -1)
+ return -1;
+ count += sub_count;
+ }
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ if (TYPE_LENGTH (t) != unitlen * count)
+ return -1;
+ return count;
+ }
+
+ case TYPE_CODE_UNION:
+ {
+ int count = 0;
+ unsigned unitlen;
+ int i;
+ for (i = 0; i < TYPE_NFIELDS (t); i++)
+ {
+ int sub_count = arm_vfp_cprc_sub_candidate (TYPE_FIELD_TYPE (t, i),
+ base_type);
+ if (sub_count == -1)
+ return -1;
+ count = (count > sub_count ? count : sub_count);
+ }
+ if (TYPE_LENGTH (t) == 0)
+ {
+ gdb_assert (count == 0);
+ return 0;
+ }
+ else if (count == 0)
+ return -1;
+ unitlen = arm_vfp_cprc_unit_length (*base_type);
+ if (TYPE_LENGTH (t) != unitlen * count)
+ return -1;
+ return count;
+ }
+
+ default:
+ break;
+ }
+
+ return -1;
+}
+
+/* Determine whether T is a VFP co-processor register candidate (CPRC)
+ if passed to or returned from a non-variadic function with the VFP
+ ABI in effect. Return 1 if it is, 0 otherwise. If it is, set
+ *BASE_TYPE to the base type for T and *COUNT to the number of
+ elements of that base type before returning. */
+
+static int
+arm_vfp_call_candidate (struct type *t, enum arm_vfp_cprc_base_type *base_type,
+ int *count)
+{
+ enum arm_vfp_cprc_base_type b = VFP_CPRC_UNKNOWN;
+ int c = arm_vfp_cprc_sub_candidate (t, &b);
+ if (c <= 0 || c > 4)
+ return 0;
+ *base_type = b;
+ *count = c;
+ return 1;
+}
+
+/* Return 1 if the VFP ABI should be used for passing arguments to and
+ returning values from a function of type FUNC_TYPE, 0
+ otherwise. */
+
+static int
+arm_vfp_abi_for_function (struct gdbarch *gdbarch, struct type *func_type)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ /* Variadic functions always use the base ABI. Assume that functions
+ without debug info are not variadic. */
+ if (func_type && TYPE_VARARGS (check_typedef (func_type)))
+ return 0;
+ /* The VFP ABI is only supported as a variant of AAPCS. */
+ if (tdep->arm_abi != ARM_ABI_AAPCS)
+ return 0;
+ return gdbarch_tdep (gdbarch)->fp_model == ARM_FLOAT_VFP;
+}
+
+/* We currently only support passing parameters in integer registers, which
+ conforms with GCC's default model, and VFP argument passing following
+ the VFP variant of AAPCS. Several other variants exist and
we should probably support some of them based on the selected ABI. */
static CORE_ADDR
struct value **args, CORE_ADDR sp, int struct_return,
CORE_ADDR struct_addr)
{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int argnum;
int argreg;
int nstack;
struct stack_item *si = NULL;
+ int use_vfp_abi;
+ struct type *ftype;
+ unsigned vfp_regs_free = (1 << 16) - 1;
+
+ /* Determine the type of this function and whether the VFP ABI
+ applies. */
+ ftype = check_typedef (value_type (function));
+ if (TYPE_CODE (ftype) == TYPE_CODE_PTR)
+ ftype = check_typedef (TYPE_TARGET_TYPE (ftype));
+ use_vfp_abi = arm_vfp_abi_for_function (gdbarch, ftype);
/* Set the return address. For the ARM, the return breakpoint is
always at BP_ADDR. */
- /* XXX Fix for Thumb. */
+ if (arm_pc_is_thumb (bp_addr))
+ bp_addr |= 1;
regcache_cooked_write_unsigned (regcache, ARM_LR_REGNUM, bp_addr);
/* Walk through the list of args and determine how large a temporary
if (struct_return)
{
if (arm_debug)
- fprintf_unfiltered (gdb_stdlog, "struct return in %s = 0x%s\n",
+ fprintf_unfiltered (gdb_stdlog, "struct return in %s = %s\n",
gdbarch_register_name (gdbarch, argreg),
- paddr (struct_addr));
+ paddress (gdbarch, struct_addr));
regcache_cooked_write_unsigned (regcache, argreg, struct_addr);
argreg++;
}
enum type_code typecode;
bfd_byte *val;
int align;
+ enum arm_vfp_cprc_base_type vfp_base_type;
+ int vfp_base_count;
+ int may_use_core_reg = 1;
arg_type = check_typedef (value_type (args[argnum]));
len = TYPE_LENGTH (arg_type);
align = INT_REGISTER_SIZE * 2;
}
+ if (use_vfp_abi
+ && arm_vfp_call_candidate (arg_type, &vfp_base_type,
+ &vfp_base_count))
+ {
+ int regno;
+ int unit_length;
+ int shift;
+ unsigned mask;
+
+ /* Because this is a CPRC it cannot go in a core register or
+ cause a core register to be skipped for alignment.
+ Either it goes in VFP registers and the rest of this loop
+ iteration is skipped for this argument, or it goes on the
+ stack (and the stack alignment code is correct for this
+ case). */
+ may_use_core_reg = 0;
+
+ unit_length = arm_vfp_cprc_unit_length (vfp_base_type);
+ shift = unit_length / 4;
+ mask = (1 << (shift * vfp_base_count)) - 1;
+ for (regno = 0; regno < 16; regno += shift)
+ if (((vfp_regs_free >> regno) & mask) == mask)
+ break;
+
+ if (regno < 16)
+ {
+ int reg_char;
+ int reg_scaled;
+ int i;
+
+ vfp_regs_free &= ~(mask << regno);
+ reg_scaled = regno / shift;
+ reg_char = arm_vfp_cprc_reg_char (vfp_base_type);
+ for (i = 0; i < vfp_base_count; i++)
+ {
+ char name_buf[4];
+ int regnum;
+ if (reg_char == 'q')
+ arm_neon_quad_write (gdbarch, regcache, reg_scaled + i,
+ val + i * unit_length);
+ else
+ {
+ sprintf (name_buf, "%c%d", reg_char, reg_scaled + i);
+ regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ regcache_cooked_write (regcache, regnum,
+ val + i * unit_length);
+ }
+ }
+ continue;
+ }
+ else
+ {
+ /* This CPRC could not go in VFP registers, so all VFP
+ registers are now marked as used. */
+ vfp_regs_free = 0;
+ }
+ }
+
/* Push stack padding for dowubleword alignment. */
if (nstack & (align - 1))
{
}
/* Doubleword aligned quantities must go in even register pairs. */
- if (argreg <= ARM_LAST_ARG_REGNUM
+ if (may_use_core_reg
+ && argreg <= ARM_LAST_ARG_REGNUM
&& align > INT_REGISTER_SIZE
&& argreg & 1)
argreg++;
&& target_type != NULL
&& TYPE_CODE_FUNC == TYPE_CODE (target_type))
{
- CORE_ADDR regval = extract_unsigned_integer (val, len);
+ CORE_ADDR regval = extract_unsigned_integer (val, len, byte_order);
if (arm_pc_is_thumb (regval))
{
val = alloca (len);
- store_unsigned_integer (val, len, MAKE_THUMB_ADDR (regval));
+ store_unsigned_integer (val, len, byte_order,
+ MAKE_THUMB_ADDR (regval));
}
}
{
int partial_len = len < INT_REGISTER_SIZE ? len : INT_REGISTER_SIZE;
- if (argreg <= ARM_LAST_ARG_REGNUM)
+ if (may_use_core_reg && argreg <= ARM_LAST_ARG_REGNUM)
{
/* The argument is being passed in a general purpose
register. */
- CORE_ADDR regval = extract_unsigned_integer (val, partial_len);
- if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ CORE_ADDR regval
+ = extract_unsigned_integer (val, partial_len, byte_order);
+ if (byte_order == BFD_ENDIAN_BIG)
regval <<= (INT_REGISTER_SIZE - partial_len) * 8;
if (arm_debug)
fprintf_unfiltered (gdb_stdlog, "arg %d in %s = 0x%s\n",
print_fpu_flags (status);
}
+/* Construct the ARM extended floating point type. */
+static struct type *
+arm_ext_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (!tdep->arm_ext_type)
+ tdep->arm_ext_type
+ = arch_float_type (gdbarch, -1, "builtin_type_arm_ext",
+ floatformats_arm_ext);
+
+ return tdep->arm_ext_type;
+}
+
+static struct type *
+arm_neon_double_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->neon_double_type == NULL)
+ {
+ struct type *t, *elem;
+
+ t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_d",
+ TYPE_CODE_UNION);
+ elem = builtin_type (gdbarch)->builtin_uint8;
+ append_composite_type_field (t, "u8", init_vector_type (elem, 8));
+ elem = builtin_type (gdbarch)->builtin_uint16;
+ append_composite_type_field (t, "u16", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_uint32;
+ append_composite_type_field (t, "u32", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_uint64;
+ append_composite_type_field (t, "u64", elem);
+ elem = builtin_type (gdbarch)->builtin_float;
+ append_composite_type_field (t, "f32", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_double;
+ append_composite_type_field (t, "f64", elem);
+
+ TYPE_VECTOR (t) = 1;
+ TYPE_NAME (t) = "neon_d";
+ tdep->neon_double_type = t;
+ }
+
+ return tdep->neon_double_type;
+}
+
+/* FIXME: The vector types are not correctly ordered on big-endian
+ targets. Just as s0 is the low bits of d0, d0[0] is also the low
+ bits of d0 - regardless of what unit size is being held in d0. So
+ the offset of the first uint8 in d0 is 7, but the offset of the
+ first float is 4. This code works as-is for little-endian
+ targets. */
+
+static struct type *
+arm_neon_quad_type (struct gdbarch *gdbarch)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ if (tdep->neon_quad_type == NULL)
+ {
+ struct type *t, *elem;
+
+ t = arch_composite_type (gdbarch, "__gdb_builtin_type_neon_q",
+ TYPE_CODE_UNION);
+ elem = builtin_type (gdbarch)->builtin_uint8;
+ append_composite_type_field (t, "u8", init_vector_type (elem, 16));
+ elem = builtin_type (gdbarch)->builtin_uint16;
+ append_composite_type_field (t, "u16", init_vector_type (elem, 8));
+ elem = builtin_type (gdbarch)->builtin_uint32;
+ append_composite_type_field (t, "u32", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_uint64;
+ append_composite_type_field (t, "u64", init_vector_type (elem, 2));
+ elem = builtin_type (gdbarch)->builtin_float;
+ append_composite_type_field (t, "f32", init_vector_type (elem, 4));
+ elem = builtin_type (gdbarch)->builtin_double;
+ append_composite_type_field (t, "f64", init_vector_type (elem, 2));
+
+ TYPE_VECTOR (t) = 1;
+ TYPE_NAME (t) = "neon_q";
+ tdep->neon_quad_type = t;
+ }
+
+ return tdep->neon_quad_type;
+}
+
/* Return the GDB type object for the "standard" data type of data in
register N. */
static struct type *
arm_register_type (struct gdbarch *gdbarch, int regnum)
{
+ int num_regs = gdbarch_num_regs (gdbarch);
+
+ if (gdbarch_tdep (gdbarch)->have_vfp_pseudos
+ && regnum >= num_regs && regnum < num_regs + 32)
+ return builtin_type (gdbarch)->builtin_float;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos
+ && regnum >= num_regs + 32 && regnum < num_regs + 32 + 16)
+ return arm_neon_quad_type (gdbarch);
+
+ /* If the target description has register information, we are only
+ in this function so that we can override the types of
+ double-precision registers for NEON. */
+ if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
+ {
+ struct type *t = tdesc_register_type (gdbarch, regnum);
+
+ if (regnum >= ARM_D0_REGNUM && regnum < ARM_D0_REGNUM + 32
+ && TYPE_CODE (t) == TYPE_CODE_FLT
+ && gdbarch_tdep (gdbarch)->have_neon)
+ return arm_neon_double_type (gdbarch);
+ else
+ return t;
+ }
+
if (regnum >= ARM_F0_REGNUM && regnum < ARM_F0_REGNUM + NUM_FREGS)
- return builtin_type_arm_ext;
+ {
+ if (!gdbarch_tdep (gdbarch)->have_fpa_registers)
+ return builtin_type (gdbarch)->builtin_void;
+
+ return arm_ext_type (gdbarch);
+ }
else if (regnum == ARM_SP_REGNUM)
- return builtin_type_void_data_ptr;
+ return builtin_type (gdbarch)->builtin_data_ptr;
else if (regnum == ARM_PC_REGNUM)
- return builtin_type_void_func_ptr;
+ return builtin_type (gdbarch)->builtin_func_ptr;
else if (regnum >= ARRAY_SIZE (arm_register_names))
/* These registers are only supported on targets which supply
an XML description. */
- return builtin_type_int0;
+ return builtin_type (gdbarch)->builtin_int0;
else
- return builtin_type_uint32;
+ return builtin_type (gdbarch)->builtin_uint32;
}
/* Map a DWARF register REGNUM onto the appropriate GDB register
if (reg >= 192 && reg <= 199)
return ARM_WC0_REGNUM + reg - 192;
+ /* VFP v2 registers. A double precision value is actually
+ in d1 rather than s2, but the ABI only defines numbering
+ for the single precision registers. This will "just work"
+ in GDB for little endian targets (we'll read eight bytes,
+ starting in s0 and then progressing to s1), but will be
+ reversed on big endian targets with VFP. This won't
+ be a problem for the new Neon quad registers; you're supposed
+ to use DW_OP_piece for those. */
+ if (reg >= 64 && reg <= 95)
+ {
+ char name_buf[4];
+
+ sprintf (name_buf, "s%d", reg - 64);
+ return user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ }
+
+ /* VFP v3 / Neon registers. This range is also used for VFP v2
+ registers, except that it now describes d0 instead of s0. */
+ if (reg >= 256 && reg <= 287)
+ {
+ char name_buf[4];
+
+ sprintf (name_buf, "d%d", reg - 256);
+ return user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ }
+
return -1;
}
case INST_LT:
return (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0));
case INST_GT:
- return (((status_reg & FLAG_Z) == 0) &&
- (((status_reg & FLAG_N) == 0) == ((status_reg & FLAG_V) == 0)));
+ return (((status_reg & FLAG_Z) == 0)
+ && (((status_reg & FLAG_N) == 0)
+ == ((status_reg & FLAG_V) == 0)));
case INST_LE:
- return (((status_reg & FLAG_Z) != 0) ||
- (((status_reg & FLAG_N) == 0) != ((status_reg & FLAG_V) == 0)));
+ return (((status_reg & FLAG_Z) != 0)
+ || (((status_reg & FLAG_N) == 0)
+ != ((status_reg & FLAG_V) == 0)));
}
return 1;
}
thumb_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
{
struct gdbarch *gdbarch = get_frame_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
unsigned long pc_val = ((unsigned long) pc) + 4; /* PC after prefetch */
- unsigned short inst1 = read_memory_unsigned_integer (pc, 2);
+ unsigned short inst1;
CORE_ADDR nextpc = pc + 2; /* default is next instruction */
unsigned long offset;
+ ULONGEST status, it;
+
+ inst1 = read_memory_unsigned_integer (pc, 2, byte_order_for_code);
+
+ /* Thumb-2 conditional execution support. There are eight bits in
+ the CPSR which describe conditional execution state. Once
+ reconstructed (they're in a funny order), the low five bits
+ describe the low bit of the condition for each instruction and
+ how many instructions remain. The high three bits describe the
+ base condition. One of the low four bits will be set if an IT
+ block is active. These bits read as zero on earlier
+ processors. */
+ status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+ it = ((status >> 8) & 0xfc) | ((status >> 25) & 0x3);
+
+ /* On GNU/Linux, where this routine is used, we use an undefined
+ instruction as a breakpoint. Unlike BKPT, IT can disable execution
+ of the undefined instruction. So we might miss the breakpoint! */
+ if (((inst1 & 0xff00) == 0xbf00 && (inst1 & 0x000f) != 0) || (it & 0x0f))
+ error (_("Stepping through Thumb-2 IT blocks is not yet supported"));
+
+ if (it & 0x0f)
+ {
+ /* We are in a conditional block. Check the condition. */
+ int cond = it >> 4;
+
+ if (! condition_true (cond, status))
+ {
+ /* Advance to the next instruction. All the 32-bit
+ instructions share a common prefix. */
+ if ((inst1 & 0xe000) == 0xe000 && (inst1 & 0x1800) != 0)
+ return pc + 4;
+ else
+ return pc + 2;
+ }
+ }
if ((inst1 & 0xff00) == 0xbd00) /* pop {rlist, pc} */
{
all of the other registers. */
offset = bitcount (bits (inst1, 0, 7)) * INT_REGISTER_SIZE;
sp = get_frame_register_unsigned (frame, ARM_SP_REGNUM);
- nextpc = (CORE_ADDR) read_memory_unsigned_integer (sp + offset, 4);
+ nextpc = read_memory_unsigned_integer (sp + offset, 4, byte_order);
nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
if (nextpc == pc)
error (_("Infinite loop detected"));
}
else if ((inst1 & 0xf000) == 0xd000) /* conditional branch */
{
- unsigned long status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
unsigned long cond = bits (inst1, 8, 11);
if (cond != 0x0f && condition_true (cond, status)) /* 0x0f = SWI */
nextpc = pc_val + (sbits (inst1, 0, 7) << 1);
{
nextpc = pc_val + (sbits (inst1, 0, 10) << 1);
}
- else if ((inst1 & 0xf800) == 0xf000) /* long branch with link, and blx */
- {
- unsigned short inst2 = read_memory_unsigned_integer (pc + 2, 2);
- offset = (sbits (inst1, 0, 10) << 12) + (bits (inst2, 0, 10) << 1);
- nextpc = pc_val + offset;
- /* For BLX make sure to clear the low bits. */
- if (bits (inst2, 11, 12) == 1)
- nextpc = nextpc & 0xfffffffc;
- }
- else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
+ else if ((inst1 & 0xe000) == 0xe000) /* 32-bit instruction */
{
- if (bits (inst1, 3, 6) == 0x0f)
- nextpc = pc_val;
- else
- nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+ unsigned short inst2;
+ inst2 = read_memory_unsigned_integer (pc + 2, 2, byte_order_for_code);
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- }
+ /* Default to the next instruction. */
+ nextpc = pc + 4;
- return nextpc;
-}
+ if ((inst1 & 0xf800) == 0xf000 && (inst2 & 0x8000) == 0x8000)
+ {
+ /* Branches and miscellaneous control instructions. */
-CORE_ADDR
-arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
-{
- struct gdbarch *gdbarch = get_frame_arch (frame);
- unsigned long pc_val;
- unsigned long this_instr;
- unsigned long status;
- CORE_ADDR nextpc;
+ if ((inst2 & 0x1000) != 0 || (inst2 & 0xd001) == 0xc000)
+ {
+ /* B, BL, BLX. */
+ int j1, j2, imm1, imm2;
- if (arm_frame_is_thumb (frame))
- return thumb_get_next_pc (frame, pc);
+ imm1 = sbits (inst1, 0, 10);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
- pc_val = (unsigned long) pc;
- this_instr = read_memory_unsigned_integer (pc, 4);
- status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
- nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
+ offset = ((imm1 << 12) + (imm2 << 1));
+ offset ^= ((!j2) << 22) | ((!j1) << 23);
- if (bits (this_instr, 28, 31) == INST_NV)
- switch (bits (this_instr, 24, 27))
- {
- case 0xa:
- case 0xb:
- {
- /* Branch with Link and change to Thumb. */
- nextpc = BranchDest (pc, this_instr);
- nextpc |= bit (this_instr, 24) << 1;
+ nextpc = pc_val + offset;
+ /* For BLX make sure to clear the low bits. */
+ if (bit (inst2, 12) == 0)
+ nextpc = nextpc & 0xfffffffc;
+ }
+ else if (inst1 == 0xf3de && (inst2 & 0xff00) == 0x3f00)
+ {
+ /* SUBS PC, LR, #imm8. */
+ nextpc = get_frame_register_unsigned (frame, ARM_LR_REGNUM);
+ nextpc -= inst2 & 0x00ff;
+ }
+ else if ((inst2 & 0xd000) == 0xc000 && (inst1 & 0x0380) != 0x0380)
+ {
+ /* Conditional branch. */
+ if (condition_true (bits (inst1, 6, 9), status))
+ {
+ int sign, j1, j2, imm1, imm2;
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- break;
+ sign = sbits (inst1, 10, 10);
+ imm1 = bits (inst1, 0, 5);
+ imm2 = bits (inst2, 0, 10);
+ j1 = bit (inst2, 13);
+ j2 = bit (inst2, 11);
+
+ offset = (sign << 20) + (j2 << 19) + (j1 << 18);
+ offset += (imm1 << 12) + (imm2 << 1);
+
+ nextpc = pc_val + offset;
+ }
+ }
}
- case 0xc:
+ else if ((inst1 & 0xfe50) == 0xe810)
+ {
+ /* Load multiple or RFE. */
+ int rn, offset, load_pc = 1;
+
+ rn = bits (inst1, 0, 3);
+ if (bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* LDMIA or POP */
+ if (!bit (inst2, 15))
+ load_pc = 0;
+ offset = bitcount (inst2) * 4 - 4;
+ }
+ else if (!bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* LDMDB */
+ if (!bit (inst2, 15))
+ load_pc = 0;
+ offset = -4;
+ }
+ else if (bit (inst1, 7) && bit (inst1, 8))
+ {
+ /* RFEIA */
+ offset = 0;
+ }
+ else if (!bit (inst1, 7) && !bit (inst1, 8))
+ {
+ /* RFEDB */
+ offset = -8;
+ }
+ else
+ load_pc = 0;
+
+ if (load_pc)
+ {
+ CORE_ADDR addr = get_frame_register_unsigned (frame, rn);
+ nextpc = get_frame_memory_unsigned (frame, addr + offset, 4);
+ }
+ }
+ else if ((inst1 & 0xffef) == 0xea4f && (inst2 & 0xfff0) == 0x0f00)
+ {
+ /* MOV PC or MOVS PC. */
+ nextpc = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ }
+ else if ((inst1 & 0xff70) == 0xf850 && (inst2 & 0xf000) == 0xf000)
+ {
+ /* LDR PC. */
+ CORE_ADDR base;
+ int rn, load_pc = 1;
+
+ rn = bits (inst1, 0, 3);
+ base = get_frame_register_unsigned (frame, rn);
+ if (rn == 15)
+ {
+ base = (base + 4) & ~(CORE_ADDR) 0x3;
+ if (bit (inst1, 7))
+ base += bits (inst2, 0, 11);
+ else
+ base -= bits (inst2, 0, 11);
+ }
+ else if (bit (inst1, 7))
+ base += bits (inst2, 0, 11);
+ else if (bit (inst2, 11))
+ {
+ if (bit (inst2, 10))
+ {
+ if (bit (inst2, 9))
+ base += bits (inst2, 0, 7);
+ else
+ base -= bits (inst2, 0, 7);
+ }
+ }
+ else if ((inst2 & 0x0fc0) == 0x0000)
+ {
+ int shift = bits (inst2, 4, 5), rm = bits (inst2, 0, 3);
+ base += get_frame_register_unsigned (frame, rm) << shift;
+ }
+ else
+ /* Reserved. */
+ load_pc = 0;
+
+ if (load_pc)
+ nextpc = get_frame_memory_unsigned (frame, base, 4);
+ }
+ else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
+ {
+ /* TBB. */
+ CORE_ADDR table, offset, length;
+
+ table = get_frame_register_unsigned (frame, bits (inst1, 0, 3));
+ offset = get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ length = 2 * get_frame_memory_unsigned (frame, table + offset, 1);
+ nextpc = pc_val + length;
+ }
+ else if ((inst1 & 0xfff0) == 0xe8d0 && (inst2 & 0xfff0) == 0xf000)
+ {
+ /* TBH. */
+ CORE_ADDR table, offset, length;
+
+ table = get_frame_register_unsigned (frame, bits (inst1, 0, 3));
+ offset = 2 * get_frame_register_unsigned (frame, bits (inst2, 0, 3));
+ length = 2 * get_frame_memory_unsigned (frame, table + offset, 2);
+ nextpc = pc_val + length;
+ }
+ }
+ else if ((inst1 & 0xff00) == 0x4700) /* bx REG, blx REG */
+ {
+ if (bits (inst1, 3, 6) == 0x0f)
+ nextpc = pc_val;
+ else
+ nextpc = get_frame_register_unsigned (frame, bits (inst1, 3, 6));
+
+ nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ }
+ else if ((inst1 & 0xf500) == 0xb100)
+ {
+ /* CBNZ or CBZ. */
+ int imm = (bit (inst1, 9) << 6) + (bits (inst1, 3, 7) << 1);
+ ULONGEST reg = get_frame_register_unsigned (frame, bits (inst1, 0, 2));
+
+ if (bit (inst1, 11) && reg != 0)
+ nextpc = pc_val + imm;
+ else if (!bit (inst1, 11) && reg == 0)
+ nextpc = pc_val + imm;
+ }
+
+ return nextpc;
+}
+
+CORE_ADDR
+arm_get_next_pc (struct frame_info *frame, CORE_ADDR pc)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ unsigned long pc_val;
+ unsigned long this_instr;
+ unsigned long status;
+ CORE_ADDR nextpc;
+
+ if (arm_frame_is_thumb (frame))
+ return thumb_get_next_pc (frame, pc);
+
+ pc_val = (unsigned long) pc;
+ this_instr = read_memory_unsigned_integer (pc, 4, byte_order_for_code);
+
+ status = get_frame_register_unsigned (frame, ARM_PS_REGNUM);
+ nextpc = (CORE_ADDR) (pc_val + 4); /* Default case */
+
+ if (bits (this_instr, 28, 31) == INST_NV)
+ switch (bits (this_instr, 24, 27))
+ {
+ case 0xa:
+ case 0xb:
+ {
+ /* Branch with Link and change to Thumb. */
+ nextpc = BranchDest (pc, this_instr);
+ nextpc |= bit (this_instr, 24) << 1;
+
+ nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ break;
+ }
+ case 0xc:
case 0xd:
case 0xe:
/* Coprocessor register transfer. */
? shifted_reg_val (frame, this_instr, c, pc_val, status)
: bits (this_instr, 0, 11));
- if (bit (this_instr, 23))
- base += offset;
- else
- base -= offset;
- }
- nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
- 4);
+ if (bit (this_instr, 23))
+ base += offset;
+ else
+ base -= offset;
+ }
+ nextpc = (CORE_ADDR) read_memory_integer ((CORE_ADDR) base,
+ 4, byte_order);
+
+ nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
+
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ }
+ }
+ break;
+
+ case 0x8:
+ case 0x9: /* block transfer */
+ if (bit (this_instr, 20))
+ {
+ /* LDM */
+ if (bit (this_instr, 15))
+ {
+ /* loading pc */
+ int offset = 0;
+
+ if (bit (this_instr, 23))
+ {
+ /* up */
+ unsigned long reglist = bits (this_instr, 0, 14);
+ offset = bitcount (reglist) * 4;
+ if (bit (this_instr, 24)) /* pre */
+ offset += 4;
+ }
+ else if (bit (this_instr, 24))
+ offset = -4;
+
+ {
+ unsigned long rn_val =
+ get_frame_register_unsigned (frame,
+ bits (this_instr, 16, 19));
+ nextpc =
+ (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
+ + offset),
+ 4, byte_order);
+ }
+ nextpc = gdbarch_addr_bits_remove
+ (gdbarch, nextpc);
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ }
+ }
+ break;
+
+ case 0xb: /* branch & link */
+ case 0xa: /* branch */
+ {
+ nextpc = BranchDest (pc, this_instr);
+
+ nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
+ if (nextpc == pc)
+ error (_("Infinite loop detected"));
+ break;
+ }
+
+ case 0xc:
+ case 0xd:
+ case 0xe: /* coproc ops */
+ case 0xf: /* SWI */
+ break;
+
+ default:
+ fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
+ return (pc);
+ }
+ }
+
+ return nextpc;
+}
+
+/* single_step() is called just before we want to resume the inferior,
+ if we want to single-step it but there is no hardware or kernel
+ single-step support. We find the target of the coming instruction
+ and breakpoint it. */
+
+int
+arm_software_single_step (struct frame_info *frame)
+{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct address_space *aspace = get_frame_address_space (frame);
+
+ /* NOTE: This may insert the wrong breakpoint instruction when
+ single-stepping over a mode-changing instruction, if the
+ CPSR heuristics are used. */
+
+ CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame));
+ insert_single_step_breakpoint (gdbarch, aspace, next_pc);
+
+ return 1;
+}
+
+/* ARM displaced stepping support.
+
+ Generally ARM displaced stepping works as follows:
+
+ 1. When an instruction is to be single-stepped, it is first decoded by
+ arm_process_displaced_insn (called from arm_displaced_step_copy_insn).
+ Depending on the type of instruction, it is then copied to a scratch
+ location, possibly in a modified form. The copy_* set of functions
+ performs such modification, as necessary. A breakpoint is placed after
+ the modified instruction in the scratch space to return control to GDB.
+ Note in particular that instructions which modify the PC will no longer
+ do so after modification.
+
+ 2. The instruction is single-stepped, by setting the PC to the scratch
+ location address, and resuming. Control returns to GDB when the
+ breakpoint is hit.
+
+ 3. A cleanup function (cleanup_*) is called corresponding to the copy_*
+ function used for the current instruction. This function's job is to
+ put the CPU/memory state back to what it would have been if the
+ instruction had been executed unmodified in its original location. */
+
+/* NOP instruction (mov r0, r0). */
+#define ARM_NOP 0xe1a00000
+
+/* Helper for register reads for displaced stepping. In particular, this
+ returns the PC as it would be seen by the instruction at its original
+ location. */
+
+ULONGEST
+displaced_read_reg (struct regcache *regs, CORE_ADDR from, int regno)
+{
+ ULONGEST ret;
+
+ if (regno == 15)
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: read pc value %.8lx\n",
+ (unsigned long) from + 8);
+ return (ULONGEST) from + 8; /* Pipeline offset. */
+ }
+ else
+ {
+ regcache_cooked_read_unsigned (regs, regno, &ret);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: read r%d value %.8lx\n",
+ regno, (unsigned long) ret);
+ return ret;
+ }
+}
+
+static int
+displaced_in_arm_mode (struct regcache *regs)
+{
+ ULONGEST ps;
+
+ regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+
+ return (ps & CPSR_T) == 0;
+}
+
+/* Write to the PC as from a branch instruction. */
+
+static void
+branch_write_pc (struct regcache *regs, ULONGEST val)
+{
+ if (displaced_in_arm_mode (regs))
+ /* Note: If bits 0/1 are set, this branch would be unpredictable for
+ architecture versions < 6. */
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & ~(ULONGEST) 0x3);
+ else
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & ~(ULONGEST) 0x1);
+}
+
+/* Write to the PC as from a branch-exchange instruction. */
+
+static void
+bx_write_pc (struct regcache *regs, ULONGEST val)
+{
+ ULONGEST ps;
+
+ regcache_cooked_read_unsigned (regs, ARM_PS_REGNUM, &ps);
+
+ if ((val & 1) == 1)
+ {
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM, ps | CPSR_T);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffe);
+ }
+ else if ((val & 2) == 0)
+ {
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM,
+ ps & ~(ULONGEST) CPSR_T);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val);
+ }
+ else
+ {
+ /* Unpredictable behaviour. Try to do something sensible (switch to ARM
+ mode, align dest to 4 bytes). */
+ warning (_("Single-stepping BX to non-word-aligned ARM instruction."));
+ regcache_cooked_write_unsigned (regs, ARM_PS_REGNUM,
+ ps & ~(ULONGEST) CPSR_T);
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, val & 0xfffffffc);
+ }
+}
+
+/* Write to the PC as if from a load instruction. */
+
+static void
+load_write_pc (struct regcache *regs, ULONGEST val)
+{
+ if (DISPLACED_STEPPING_ARCH_VERSION >= 5)
+ bx_write_pc (regs, val);
+ else
+ branch_write_pc (regs, val);
+}
+
+/* Write to the PC as if from an ALU instruction. */
+
+static void
+alu_write_pc (struct regcache *regs, ULONGEST val)
+{
+ if (DISPLACED_STEPPING_ARCH_VERSION >= 7 && displaced_in_arm_mode (regs))
+ bx_write_pc (regs, val);
+ else
+ branch_write_pc (regs, val);
+}
+
+/* Helper for writing to registers for displaced stepping. Writing to the PC
+ has a varying effects depending on the instruction which does the write:
+ this is controlled by the WRITE_PC argument. */
+
+void
+displaced_write_reg (struct regcache *regs, struct displaced_step_closure *dsc,
+ int regno, ULONGEST val, enum pc_write_style write_pc)
+{
+ if (regno == 15)
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing pc %.8lx\n",
+ (unsigned long) val);
+ switch (write_pc)
+ {
+ case BRANCH_WRITE_PC:
+ branch_write_pc (regs, val);
+ break;
+
+ case BX_WRITE_PC:
+ bx_write_pc (regs, val);
+ break;
+
+ case LOAD_WRITE_PC:
+ load_write_pc (regs, val);
+ break;
+
+ case ALU_WRITE_PC:
+ alu_write_pc (regs, val);
+ break;
+
+ case CANNOT_WRITE_PC:
+ warning (_("Instruction wrote to PC in an unexpected way when "
+ "single-stepping"));
+ break;
+
+ default:
+ internal_error (__FILE__, __LINE__,
+ _("Invalid argument to displaced_write_reg"));
+ }
+
+ dsc->wrote_to_pc = 1;
+ }
+ else
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing r%d value %.8lx\n",
+ regno, (unsigned long) val);
+ regcache_cooked_write_unsigned (regs, regno, val);
+ }
+}
+
+/* This function is used to concisely determine if an instruction INSN
+ references PC. Register fields of interest in INSN should have the
+ corresponding fields of BITMASK set to 0b1111. The function returns return 1
+ if any of these fields in INSN reference the PC (also 0b1111, r15), else it
+ returns 0. */
+
+static int
+insn_references_pc (uint32_t insn, uint32_t bitmask)
+{
+ uint32_t lowbit = 1;
+
+ while (bitmask != 0)
+ {
+ uint32_t mask;
+
+ for (; lowbit && (bitmask & lowbit) == 0; lowbit <<= 1)
+ ;
+
+ if (!lowbit)
+ break;
+
+ mask = lowbit * 0xf;
+
+ if ((insn & mask) == mask)
+ return 1;
+
+ bitmask &= ~mask;
+ }
+
+ return 0;
+}
+
+/* The simplest copy function. Many instructions have the same effect no
+ matter what address they are executed at: in those cases, use this. */
+
+static int
+copy_unmodified (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, uint32_t insn,
+ const char *iname, struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying insn %.8lx, "
+ "opcode/class '%s' unmodified\n", (unsigned long) insn,
+ iname);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
+}
+
+/* Preload instructions with immediate offset. */
+
+static void
+cleanup_preload (struct gdbarch *gdbarch ATTRIBUTE_UNUSED,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (!dsc->u.preload.immed)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+}
+
+static int
+copy_preload (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ ULONGEST rn_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000f0000ul))
+ return copy_unmodified (gdbarch, insn, "preload", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ (unsigned long) insn);
+
+ /* Preload instructions:
+
+ {pli/pld} [rn, #+/-imm]
+ ->
+ {pli/pld} [r0, #+/-imm]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ rn_val = displaced_read_reg (regs, from, rn);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+
+ dsc->u.preload.immed = 1;
+
+ dsc->modinsn[0] = insn & 0xfff0ffff;
+
+ dsc->cleanup = &cleanup_preload;
+
+ return 0;
+}
+
+/* Preload instructions with register offset. */
+
+static int
+copy_preload_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ ULONGEST rn_val, rm_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000f000ful))
+ return copy_unmodified (gdbarch, insn, "preload reg", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying preload insn %.8lx\n",
+ (unsigned long) insn);
+
+ /* Preload register-offset instructions:
+
+ {pli/pld} [rn, rm {, shift}]
+ ->
+ {pli/pld} [r0, r1 {, shift}]. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, from, 1);
+ rn_val = displaced_read_reg (regs, from, rn);
+ rm_val = displaced_read_reg (regs, from, rm);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rm_val, CANNOT_WRITE_PC);
+
+ dsc->u.preload.immed = 0;
+
+ dsc->modinsn[0] = (insn & 0xfff0fff0) | 0x1;
+
+ dsc->cleanup = &cleanup_preload;
+
+ return 0;
+}
+
+/* Copy/cleanup coprocessor load and store instructions. */
+
+static void
+cleanup_copro_load_store (struct gdbarch *gdbarch ATTRIBUTE_UNUSED,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST rn_val = displaced_read_reg (regs, dsc->insn_addr, 0);
+
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, LOAD_WRITE_PC);
+}
+
+static int
+copy_copro_load_store (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ ULONGEST rn_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000f0000ul))
+ return copy_unmodified (gdbarch, insn, "copro load/store", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying coprocessor "
+ "load/store insn %.8lx\n", (unsigned long) insn);
+
+ /* Coprocessor load/store instructions:
+
+ {stc/stc2} [<Rn>, #+/-imm] (and other immediate addressing modes)
+ ->
+ {stc/stc2} [r0, #+/-imm].
+
+ ldc/ldc2 are handled identically. */
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ rn_val = displaced_read_reg (regs, from, rn);
+ displaced_write_reg (regs, dsc, 0, rn_val, CANNOT_WRITE_PC);
+
+ dsc->u.ldst.writeback = bit (insn, 25);
+ dsc->u.ldst.rn = rn;
+
+ dsc->modinsn[0] = insn & 0xfff0ffff;
+
+ dsc->cleanup = &cleanup_copro_load_store;
+
+ return 0;
+}
+
+/* Clean up branch instructions (actually perform the branch, by setting
+ PC). */
+
+static void
+cleanup_branch (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST from = dsc->insn_addr;
+ uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
+ int branch_taken = condition_true (dsc->u.branch.cond, status);
+ enum pc_write_style write_pc = dsc->u.branch.exchange
+ ? BX_WRITE_PC : BRANCH_WRITE_PC;
+
+ if (!branch_taken)
+ return;
+
+ if (dsc->u.branch.link)
+ {
+ ULONGEST pc = displaced_read_reg (regs, from, 15);
+ displaced_write_reg (regs, dsc, 14, pc - 4, CANNOT_WRITE_PC);
+ }
+
+ displaced_write_reg (regs, dsc, 15, dsc->u.branch.dest, write_pc);
+}
+
+/* Copy B/BL/BLX instructions with immediate destinations. */
+
+static int
+copy_b_bl_blx (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int cond = bits (insn, 28, 31);
+ int exchange = (cond == 0xf);
+ int link = exchange || bit (insn, 24);
+ CORE_ADDR from = dsc->insn_addr;
+ long offset;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s immediate insn "
+ "%.8lx\n", (exchange) ? "blx" : (link) ? "bl" : "b",
+ (unsigned long) insn);
+
+ /* Implement "BL<cond> <label>" as:
+
+ Preparation: cond <- instruction condition
+ Insn: mov r0, r0 (nop)
+ Cleanup: if (condition true) { r14 <- pc; pc <- label }.
+
+ B<cond> similar, but don't set r14 in cleanup. */
+
+ if (exchange)
+ /* For BLX, set bit 0 of the destination. The cleanup_branch function will
+ then arrange the switch into Thumb mode. */
+ offset = (bits (insn, 0, 23) << 2) | (bit (insn, 24) << 1) | 1;
+ else
+ offset = bits (insn, 0, 23) << 2;
+
+ if (bit (offset, 25))
+ offset = offset | ~0x3ffffff;
+
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = link;
+ dsc->u.branch.exchange = exchange;
+ dsc->u.branch.dest = from + 8 + offset;
+
+ dsc->modinsn[0] = ARM_NOP;
+
+ dsc->cleanup = &cleanup_branch;
+
+ return 0;
+}
+
+/* Copy BX/BLX with register-specified destinations. */
+
+static int
+copy_bx_blx_reg (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int cond = bits (insn, 28, 31);
+ /* BX: x12xxx1x
+ BLX: x12xxx3x. */
+ int link = bit (insn, 5);
+ unsigned int rm = bits (insn, 0, 3);
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s register insn "
+ "%.8lx\n", (link) ? "blx" : "bx", (unsigned long) insn);
+
+ /* Implement {BX,BLX}<cond> <reg>" as:
+
+ Preparation: cond <- instruction condition
+ Insn: mov r0, r0 (nop)
+ Cleanup: if (condition true) { r14 <- pc; pc <- dest; }.
+
+ Don't set r14 in cleanup for BX. */
+
+ dsc->u.branch.dest = displaced_read_reg (regs, from, rm);
+
+ dsc->u.branch.cond = cond;
+ dsc->u.branch.link = link;
+ dsc->u.branch.exchange = 1;
+
+ dsc->modinsn[0] = ARM_NOP;
+
+ dsc->cleanup = &cleanup_branch;
+
+ return 0;
+}
+
+/* Copy/cleanup arithmetic/logic instruction with immediate RHS. */
+
+static void
+cleanup_alu_imm (struct gdbarch *gdbarch ATTRIBUTE_UNUSED,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val = displaced_read_reg (regs, dsc->insn_addr, 0);
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
+
+static int
+copy_alu_imm (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
+ ULONGEST rd_val, rn_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000ff000ul))
+ return copy_unmodified (gdbarch, insn, "ALU immediate", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying immediate %s insn "
+ "%.8lx\n", is_mov ? "move" : "ALU",
+ (unsigned long) insn);
+
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] #imm
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2 <- r0, r1;
+ r0, r1 <- rd, rn
+ Insn: <op><cond> r0, r1, #imm
+ Cleanup: rd <- r0; r0 <- tmp1; r1 <- tmp2
+ */
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, from, 1);
+ rn_val = displaced_read_reg (regs, from, rn);
+ rd_val = displaced_read_reg (regs, from, rd);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ if (is_mov)
+ dsc->modinsn[0] = insn & 0xfff00fff;
+ else
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x10000;
+
+ dsc->cleanup = &cleanup_alu_imm;
+
+ return 0;
+}
+
+/* Copy/cleanup arithmetic/logic insns with register RHS. */
+
+static void
+cleanup_alu_reg (struct gdbarch *gdbarch ATTRIBUTE_UNUSED,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val;
+ int i;
+
+ rd_val = displaced_read_reg (regs, dsc->insn_addr, 0);
+
+ for (i = 0; i < 3; i++)
+ displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
+
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
+
+static int
+copy_alu_reg (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd);
+ ULONGEST rd_val, rn_val, rm_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return copy_unmodified (gdbarch, insn, "ALU reg", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying reg %s insn %.8lx\n",
+ is_mov ? "move" : "ALU", (unsigned long) insn);
+
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] rm [, <shift>]
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2, tmp3 <- r0, r1, r2;
+ r0, r1, r2 <- rd, rn, rm
+ Insn: <op><cond> r0, r1, r2 [, <shift>]
+ Cleanup: rd <- r0; r0, r1, r2 <- tmp1, tmp2, tmp3
+ */
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, from, 1);
+ dsc->tmp[2] = displaced_read_reg (regs, from, 2);
+ rd_val = displaced_read_reg (regs, from, rd);
+ rn_val = displaced_read_reg (regs, from, rn);
+ rm_val = displaced_read_reg (regs, from, rm);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ if (is_mov)
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x2;
+ else
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x10002;
+
+ dsc->cleanup = &cleanup_alu_reg;
+
+ return 0;
+}
+
+/* Cleanup/copy arithmetic/logic insns with shifted register RHS. */
+
+static void
+cleanup_alu_shifted_reg (struct gdbarch *gdbarch ATTRIBUTE_UNUSED,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST rd_val = displaced_read_reg (regs, dsc->insn_addr, 0);
+ int i;
+
+ for (i = 0; i < 4; i++)
+ displaced_write_reg (regs, dsc, i, dsc->tmp[i], CANNOT_WRITE_PC);
+
+ displaced_write_reg (regs, dsc, dsc->rd, rd_val, ALU_WRITE_PC);
+}
+
+static int
+copy_alu_shifted_reg (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ unsigned int rd = bits (insn, 12, 15);
+ unsigned int rs = bits (insn, 8, 11);
+ unsigned int op = bits (insn, 21, 24);
+ int is_mov = (op == 0xd), i;
+ ULONGEST rd_val, rn_val, rm_val, rs_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000fff0ful))
+ return copy_unmodified (gdbarch, insn, "ALU shifted reg", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying shifted reg %s insn "
+ "%.8lx\n", is_mov ? "move" : "ALU",
+ (unsigned long) insn);
+
+ /* Instruction is of form:
+
+ <op><cond> rd, [rn,] rm, <shift> rs
+
+ Rewrite as:
+
+ Preparation: tmp1, tmp2, tmp3, tmp4 <- r0, r1, r2, r3
+ r0, r1, r2, r3 <- rd, rn, rm, rs
+ Insn: <op><cond> r0, r1, r2, <shift> r3
+ Cleanup: tmp5 <- r0
+ r0, r1, r2, r3 <- tmp1, tmp2, tmp3, tmp4
+ rd <- tmp5
+ */
+
+ for (i = 0; i < 4; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, from, i);
+
+ rd_val = displaced_read_reg (regs, from, rd);
+ rn_val = displaced_read_reg (regs, from, rn);
+ rm_val = displaced_read_reg (regs, from, rm);
+ rs_val = displaced_read_reg (regs, from, rs);
+ displaced_write_reg (regs, dsc, 0, rd_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 1, rn_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rm_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 3, rs_val, CANNOT_WRITE_PC);
+ dsc->rd = rd;
+
+ if (is_mov)
+ dsc->modinsn[0] = (insn & 0xfff000f0) | 0x302;
+ else
+ dsc->modinsn[0] = (insn & 0xfff000f0) | 0x10302;
+
+ dsc->cleanup = &cleanup_alu_shifted_reg;
+
+ return 0;
+}
+
+/* Clean up load instructions. */
+
+static void
+cleanup_load (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST rt_val, rt_val2 = 0, rn_val;
+ CORE_ADDR from = dsc->insn_addr;
+
+ rt_val = displaced_read_reg (regs, from, 0);
+ if (dsc->u.ldst.xfersize == 8)
+ rt_val2 = displaced_read_reg (regs, from, 1);
+ rn_val = displaced_read_reg (regs, from, 2);
+
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (dsc->u.ldst.xfersize > 4)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.immed)
+ displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+
+ /* Handle register writeback. */
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
+ /* Put result in right place. */
+ displaced_write_reg (regs, dsc, dsc->rd, rt_val, LOAD_WRITE_PC);
+ if (dsc->u.ldst.xfersize == 8)
+ displaced_write_reg (regs, dsc, dsc->rd + 1, rt_val2, LOAD_WRITE_PC);
+}
+
+/* Clean up store instructions. */
+
+static void
+cleanup_store (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ CORE_ADDR from = dsc->insn_addr;
+ ULONGEST rn_val = displaced_read_reg (regs, from, 2);
+
+ displaced_write_reg (regs, dsc, 0, dsc->tmp[0], CANNOT_WRITE_PC);
+ if (dsc->u.ldst.xfersize > 4)
+ displaced_write_reg (regs, dsc, 1, dsc->tmp[1], CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, dsc->tmp[2], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.immed)
+ displaced_write_reg (regs, dsc, 3, dsc->tmp[3], CANNOT_WRITE_PC);
+ if (!dsc->u.ldst.restore_r4)
+ displaced_write_reg (regs, dsc, 4, dsc->tmp[4], CANNOT_WRITE_PC);
+
+ /* Writeback. */
+ if (dsc->u.ldst.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.ldst.rn, rn_val, CANNOT_WRITE_PC);
+}
+
+/* Copy "extra" load/store instructions. These are halfword/doubleword
+ transfers, which have a different encoding to byte/word transfers. */
+
+static int
+copy_extra_ld_st (struct gdbarch *gdbarch, uint32_t insn, int unpriveleged,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int op1 = bits (insn, 20, 24);
+ unsigned int op2 = bits (insn, 5, 6);
+ unsigned int rt = bits (insn, 12, 15);
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3);
+ char load[12] = {0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1};
+ char bytesize[12] = {2, 2, 2, 2, 8, 1, 8, 1, 8, 2, 8, 2};
+ int immed = (op1 & 0x4) != 0;
+ int opcode;
+ ULONGEST rt_val, rt_val2 = 0, rn_val, rm_val = 0;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return copy_unmodified (gdbarch, insn, "extra load/store", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %sextra load/store "
+ "insn %.8lx\n", unpriveleged ? "unpriveleged " : "",
+ (unsigned long) insn);
+
+ opcode = ((op2 << 2) | (op1 & 0x1) | ((op1 & 0x4) >> 1)) - 4;
+
+ if (opcode < 0)
+ internal_error (__FILE__, __LINE__,
+ _("copy_extra_ld_st: instruction decode error"));
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ dsc->tmp[1] = displaced_read_reg (regs, from, 1);
+ dsc->tmp[2] = displaced_read_reg (regs, from, 2);
+ if (!immed)
+ dsc->tmp[3] = displaced_read_reg (regs, from, 3);
+
+ rt_val = displaced_read_reg (regs, from, rt);
+ if (bytesize[opcode] == 8)
+ rt_val2 = displaced_read_reg (regs, from, rt + 1);
+ rn_val = displaced_read_reg (regs, from, rn);
+ if (!immed)
+ rm_val = displaced_read_reg (regs, from, rm);
+
+ displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
+ if (bytesize[opcode] == 8)
+ displaced_write_reg (regs, dsc, 1, rt_val2, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
+ if (!immed)
+ displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = bytesize[opcode];
+ dsc->u.ldst.rn = rn;
+ dsc->u.ldst.immed = immed;
+ dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
+ dsc->u.ldst.restore_r4 = 0;
+
+ if (immed)
+ /* {ldr,str}<width><cond> rt, [rt2,] [rn, #imm]
+ ->
+ {ldr,str}<width><cond> r0, [r1,] [r2, #imm]. */
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
+ else
+ /* {ldr,str}<width><cond> rt, [rt2,] [rn, +/-rm]
+ ->
+ {ldr,str}<width><cond> r0, [r1,] [r2, +/-r3]. */
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+
+ dsc->cleanup = load[opcode] ? &cleanup_load : &cleanup_store;
+
+ return 0;
+}
+
+/* Copy byte/word loads and stores. */
+
+static int
+copy_ldr_str_ldrb_strb (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc, int load, int byte,
+ int usermode)
+{
+ int immed = !bit (insn, 25);
+ unsigned int rt = bits (insn, 12, 15);
+ unsigned int rn = bits (insn, 16, 19);
+ unsigned int rm = bits (insn, 0, 3); /* Only valid if !immed. */
+ ULONGEST rt_val, rn_val, rm_val = 0;
+ CORE_ADDR from = dsc->insn_addr;
+
+ if (!insn_references_pc (insn, 0x000ff00ful))
+ return copy_unmodified (gdbarch, insn, "load/store", dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying %s%s insn %.8lx\n",
+ load ? (byte ? "ldrb" : "ldr")
+ : (byte ? "strb" : "str"), usermode ? "t" : "",
+ (unsigned long) insn);
+
+ dsc->tmp[0] = displaced_read_reg (regs, from, 0);
+ dsc->tmp[2] = displaced_read_reg (regs, from, 2);
+ if (!immed)
+ dsc->tmp[3] = displaced_read_reg (regs, from, 3);
+ if (!load)
+ dsc->tmp[4] = displaced_read_reg (regs, from, 4);
+
+ rt_val = displaced_read_reg (regs, from, rt);
+ rn_val = displaced_read_reg (regs, from, rn);
+ if (!immed)
+ rm_val = displaced_read_reg (regs, from, rm);
+
+ displaced_write_reg (regs, dsc, 0, rt_val, CANNOT_WRITE_PC);
+ displaced_write_reg (regs, dsc, 2, rn_val, CANNOT_WRITE_PC);
+ if (!immed)
+ displaced_write_reg (regs, dsc, 3, rm_val, CANNOT_WRITE_PC);
+
+ dsc->rd = rt;
+ dsc->u.ldst.xfersize = byte ? 1 : 4;
+ dsc->u.ldst.rn = rn;
+ dsc->u.ldst.immed = immed;
+ dsc->u.ldst.writeback = bit (insn, 24) == 0 || bit (insn, 21) != 0;
+
+ /* To write PC we can do:
+
+ scratch+0: str pc, temp (*temp = scratch + 8 + offset)
+ scratch+4: ldr r4, temp
+ scratch+8: sub r4, r4, pc (r4 = scratch + 8 + offset - scratch - 8 - 8)
+ scratch+12: add r4, r4, #8 (r4 = offset)
+ scratch+16: add r0, r0, r4
+ scratch+20: str r0, [r2, #imm] (or str r0, [r2, r3])
+ scratch+24: <temp>
+
+ Otherwise we don't know what value to write for PC, since the offset is
+ architecture-dependent (sometimes PC+8, sometimes PC+12). */
+
+ if (load || rt != 15)
+ {
+ dsc->u.ldst.restore_r4 = 0;
+
+ if (immed)
+ /* {ldr,str}[b]<cond> rt, [rn, #imm], etc.
+ ->
+ {ldr,str}[b]<cond> r0, [r2, #imm]. */
+ dsc->modinsn[0] = (insn & 0xfff00fff) | 0x20000;
+ else
+ /* {ldr,str}[b]<cond> rt, [rn, rm], etc.
+ ->
+ {ldr,str}[b]<cond> r0, [r2, r3]. */
+ dsc->modinsn[0] = (insn & 0xfff00ff0) | 0x20003;
+ }
+ else
+ {
+ /* We need to use r4 as scratch. Make sure it's restored afterwards. */
+ dsc->u.ldst.restore_r4 = 1;
+
+ dsc->modinsn[0] = 0xe58ff014; /* str pc, [pc, #20]. */
+ dsc->modinsn[1] = 0xe59f4010; /* ldr r4, [pc, #16]. */
+ dsc->modinsn[2] = 0xe044400f; /* sub r4, r4, pc. */
+ dsc->modinsn[3] = 0xe2844008; /* add r4, r4, #8. */
+ dsc->modinsn[4] = 0xe0800004; /* add r0, r0, r4. */
+
+ /* As above. */
+ if (immed)
+ dsc->modinsn[5] = (insn & 0xfff00fff) | 0x20000;
+ else
+ dsc->modinsn[5] = (insn & 0xfff00ff0) | 0x20003;
+
+ dsc->modinsn[6] = 0x0; /* breakpoint location. */
+ dsc->modinsn[7] = 0x0; /* scratch space. */
+
+ dsc->numinsns = 6;
+ }
+
+ dsc->cleanup = load ? &cleanup_load : &cleanup_store;
+
+ return 0;
+}
+
+/* Cleanup LDM instructions with fully-populated register list. This is an
+ unfortunate corner case: it's impossible to implement correctly by modifying
+ the instruction. The issue is as follows: we have an instruction,
+
+ ldm rN, {r0-r15}
+
+ which we must rewrite to avoid loading PC. A possible solution would be to
+ do the load in two halves, something like (with suitable cleanup
+ afterwards):
+
+ mov r8, rN
+ ldm[id][ab] r8!, {r0-r7}
+ str r7, <temp>
+ ldm[id][ab] r8, {r7-r14}
+ <bkpt>
+
+ but at present there's no suitable place for <temp>, since the scratch space
+ is overwritten before the cleanup routine is called. For now, we simply
+ emulate the instruction. */
+
+static void
+cleanup_block_load_all (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST from = dsc->insn_addr;
+ int inc = dsc->u.block.increment;
+ int bump_before = dsc->u.block.before ? (inc ? 4 : -4) : 0;
+ int bump_after = dsc->u.block.before ? 0 : (inc ? 4 : -4);
+ uint32_t regmask = dsc->u.block.regmask;
+ int regno = inc ? 0 : 15;
+ CORE_ADDR xfer_addr = dsc->u.block.xfer_addr;
+ int exception_return = dsc->u.block.load && dsc->u.block.user
+ && (regmask & 0x8000) != 0;
+ uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
+ int do_transfer = condition_true (dsc->u.block.cond, status);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ if (!do_transfer)
+ return;
+
+ /* If the instruction is ldm rN, {...pc}^, I don't think there's anything
+ sensible we can do here. Complain loudly. */
+ if (exception_return)
+ error (_("Cannot single-step exception return"));
+
+ /* We don't handle any stores here for now. */
+ gdb_assert (dsc->u.block.load != 0);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: emulating block transfer: "
+ "%s %s %s\n", dsc->u.block.load ? "ldm" : "stm",
+ dsc->u.block.increment ? "inc" : "dec",
+ dsc->u.block.before ? "before" : "after");
+
+ while (regmask)
+ {
+ uint32_t memword;
+
+ if (inc)
+ while (regno <= 15 && (regmask & (1 << regno)) == 0)
+ regno++;
+ else
+ while (regno >= 0 && (regmask & (1 << regno)) == 0)
+ regno--;
+
+ xfer_addr += bump_before;
+
+ memword = read_memory_unsigned_integer (xfer_addr, 4, byte_order);
+ displaced_write_reg (regs, dsc, regno, memword, LOAD_WRITE_PC);
+
+ xfer_addr += bump_after;
+
+ regmask &= ~(1 << regno);
+ }
+
+ if (dsc->u.block.writeback)
+ displaced_write_reg (regs, dsc, dsc->u.block.rn, xfer_addr,
+ CANNOT_WRITE_PC);
+}
+
+/* Clean up an STM which included the PC in the register list. */
+
+static void
+cleanup_block_store_pc (struct gdbarch *gdbarch, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST from = dsc->insn_addr;
+ uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
+ int store_executed = condition_true (dsc->u.block.cond, status);
+ CORE_ADDR pc_stored_at, transferred_regs = bitcount (dsc->u.block.regmask);
+ CORE_ADDR stm_insn_addr;
+ uint32_t pc_val;
+ long offset;
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+
+ /* If condition code fails, there's nothing else to do. */
+ if (!store_executed)
+ return;
+
+ if (dsc->u.block.increment)
+ {
+ pc_stored_at = dsc->u.block.xfer_addr + 4 * transferred_regs;
+
+ if (dsc->u.block.before)
+ pc_stored_at += 4;
+ }
+ else
+ {
+ pc_stored_at = dsc->u.block.xfer_addr;
+
+ if (dsc->u.block.before)
+ pc_stored_at -= 4;
+ }
+
+ pc_val = read_memory_unsigned_integer (pc_stored_at, 4, byte_order);
+ stm_insn_addr = dsc->scratch_base;
+ offset = pc_val - stm_insn_addr;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: detected PC offset %.8lx for "
+ "STM instruction\n", offset);
+
+ /* Rewrite the stored PC to the proper value for the non-displaced original
+ instruction. */
+ write_memory_unsigned_integer (pc_stored_at, 4, byte_order,
+ dsc->insn_addr + offset);
+}
+
+/* Clean up an LDM which includes the PC in the register list. We clumped all
+ the registers in the transferred list into a contiguous range r0...rX (to
+ avoid loading PC directly and losing control of the debugged program), so we
+ must undo that here. */
+
+static void
+cleanup_block_load_pc (struct gdbarch *gdbarch ATTRIBUTE_UNUSED,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ ULONGEST from = dsc->insn_addr;
+ uint32_t status = displaced_read_reg (regs, from, ARM_PS_REGNUM);
+ int load_executed = condition_true (dsc->u.block.cond, status), i;
+ unsigned int mask = dsc->u.block.regmask, write_reg = 15;
+ unsigned int regs_loaded = bitcount (mask);
+ unsigned int num_to_shuffle = regs_loaded, clobbered;
+
+ /* The method employed here will fail if the register list is fully populated
+ (we need to avoid loading PC directly). */
+ gdb_assert (num_to_shuffle < 16);
+
+ if (!load_executed)
+ return;
+
+ clobbered = (1 << num_to_shuffle) - 1;
+
+ while (num_to_shuffle > 0)
+ {
+ if ((mask & (1 << write_reg)) != 0)
+ {
+ unsigned int read_reg = num_to_shuffle - 1;
+
+ if (read_reg != write_reg)
+ {
+ ULONGEST rval = displaced_read_reg (regs, from, read_reg);
+ displaced_write_reg (regs, dsc, write_reg, rval, LOAD_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: move "
+ "loaded register r%d to r%d\n"), read_reg,
+ write_reg);
+ }
+ else if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: register "
+ "r%d already in the right place\n"),
+ write_reg);
+
+ clobbered &= ~(1 << write_reg);
+
+ num_to_shuffle--;
+ }
+
+ write_reg--;
+ }
+
+ /* Restore any registers we scribbled over. */
+ for (write_reg = 0; clobbered != 0; write_reg++)
+ {
+ if ((clobbered & (1 << write_reg)) != 0)
+ {
+ displaced_write_reg (regs, dsc, write_reg, dsc->tmp[write_reg],
+ CANNOT_WRITE_PC);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM: restored "
+ "clobbered register r%d\n"), write_reg);
+ clobbered &= ~(1 << write_reg);
+ }
+ }
+
+ /* Perform register writeback manually. */
+ if (dsc->u.block.writeback)
+ {
+ ULONGEST new_rn_val = dsc->u.block.xfer_addr;
+
+ if (dsc->u.block.increment)
+ new_rn_val += regs_loaded * 4;
+ else
+ new_rn_val -= regs_loaded * 4;
+
+ displaced_write_reg (regs, dsc, dsc->u.block.rn, new_rn_val,
+ CANNOT_WRITE_PC);
+ }
+}
+
+/* Handle ldm/stm, apart from some tricky cases which are unlikely to occur
+ in user-level code (in particular exception return, ldm rn, {...pc}^). */
+
+static int
+copy_block_xfer (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int load = bit (insn, 20);
+ int user = bit (insn, 22);
+ int increment = bit (insn, 23);
+ int before = bit (insn, 24);
+ int writeback = bit (insn, 21);
+ int rn = bits (insn, 16, 19);
+ CORE_ADDR from = dsc->insn_addr;
+
+ /* Block transfers which don't mention PC can be run directly out-of-line. */
+ if (rn != 15 && (insn & 0x8000) == 0)
+ return copy_unmodified (gdbarch, insn, "ldm/stm", dsc);
+
+ if (rn == 15)
+ {
+ warning (_("displaced: Unpredictable LDM or STM with base register r15"));
+ return copy_unmodified (gdbarch, insn, "unpredictable ldm/stm", dsc);
+ }
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying block transfer insn "
+ "%.8lx\n", (unsigned long) insn);
+
+ dsc->u.block.xfer_addr = displaced_read_reg (regs, from, rn);
+ dsc->u.block.rn = rn;
+
+ dsc->u.block.load = load;
+ dsc->u.block.user = user;
+ dsc->u.block.increment = increment;
+ dsc->u.block.before = before;
+ dsc->u.block.writeback = writeback;
+ dsc->u.block.cond = bits (insn, 28, 31);
+
+ dsc->u.block.regmask = insn & 0xffff;
+
+ if (load)
+ {
+ if ((insn & 0xffff) == 0xffff)
+ {
+ /* LDM with a fully-populated register list. This case is
+ particularly tricky. Implement for now by fully emulating the
+ instruction (which might not behave perfectly in all cases, but
+ these instructions should be rare enough for that not to matter
+ too much). */
+ dsc->modinsn[0] = ARM_NOP;
+
+ dsc->cleanup = &cleanup_block_load_all;
+ }
+ else
+ {
+ /* LDM of a list of registers which includes PC. Implement by
+ rewriting the list of registers to be transferred into a
+ contiguous chunk r0...rX before doing the transfer, then shuffling
+ registers into the correct places in the cleanup routine. */
+ unsigned int regmask = insn & 0xffff;
+ unsigned int num_in_list = bitcount (regmask), new_regmask, bit = 1;
+ unsigned int to = 0, from = 0, i, new_rn;
+
+ for (i = 0; i < num_in_list; i++)
+ dsc->tmp[i] = displaced_read_reg (regs, from, i);
+
+ /* Writeback makes things complicated. We need to avoid clobbering
+ the base register with one of the registers in our modified
+ register list, but just using a different register can't work in
+ all cases, e.g.:
+
+ ldm r14!, {r0-r13,pc}
+
+ which would need to be rewritten as:
+
+ ldm rN!, {r0-r14}
+
+ but that can't work, because there's no free register for N.
+
+ Solve this by turning off the writeback bit, and emulating
+ writeback manually in the cleanup routine. */
+
+ if (writeback)
+ insn &= ~(1 << 21);
+
+ new_regmask = (1 << num_in_list) - 1;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, _("displaced: LDM r%d%s, "
+ "{..., pc}: original reg list %.4x, modified "
+ "list %.4x\n"), rn, writeback ? "!" : "",
+ (int) insn & 0xffff, new_regmask);
+
+ dsc->modinsn[0] = (insn & ~0xffff) | (new_regmask & 0xffff);
+
+ dsc->cleanup = &cleanup_block_load_pc;
+ }
+ }
+ else
+ {
+ /* STM of a list of registers which includes PC. Run the instruction
+ as-is, but out of line: this will store the wrong value for the PC,
+ so we must manually fix up the memory in the cleanup routine.
+ Doing things this way has the advantage that we can auto-detect
+ the offset of the PC write (which is architecture-dependent) in
+ the cleanup routine. */
+ dsc->modinsn[0] = insn;
+
+ dsc->cleanup = &cleanup_block_store_pc;
+ }
+
+ return 0;
+}
+
+/* Cleanup/copy SVC (SWI) instructions. These two functions are overridden
+ for Linux, where some SVC instructions must be treated specially. */
+
+static void
+cleanup_svc (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ CORE_ADDR from = dsc->insn_addr;
+ CORE_ADDR resume_addr = from + 4;
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: cleanup for svc, resume at "
+ "%.8lx\n", (unsigned long) resume_addr);
+
+ displaced_write_reg (regs, dsc, ARM_PC_REGNUM, resume_addr, BRANCH_WRITE_PC);
+}
+
+static int
+copy_svc (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ CORE_ADDR from = dsc->insn_addr;
+
+ /* Allow OS-specific code to override SVC handling. */
+ if (dsc->u.svc.copy_svc_os)
+ return dsc->u.svc.copy_svc_os (gdbarch, insn, to, regs, dsc);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying svc insn %.8lx\n",
+ (unsigned long) insn);
+
+ /* Preparation: none.
+ Insn: unmodified svc.
+ Cleanup: pc <- insn_addr + 4. */
+
+ dsc->modinsn[0] = insn;
+
+ dsc->cleanup = &cleanup_svc;
+ /* Pretend we wrote to the PC, so cleanup doesn't set PC to the next
+ instruction. */
+ dsc->wrote_to_pc = 1;
+
+ return 0;
+}
+
+/* Copy undefined instructions. */
+
+static int
+copy_undef (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, uint32_t insn,
+ struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying undefined insn %.8lx\n",
+ (unsigned long) insn);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
+}
+
+/* Copy unpredictable instructions. */
+
+static int
+copy_unpred (struct gdbarch *gdbarch ATTRIBUTE_UNUSED, uint32_t insn,
+ struct displaced_step_closure *dsc)
+{
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copying unpredictable insn "
+ "%.8lx\n", (unsigned long) insn);
+
+ dsc->modinsn[0] = insn;
+
+ return 0;
+}
+
+/* The decode_* functions are instruction decoding helpers. They mostly follow
+ the presentation in the ARM ARM. */
+
+static int
+decode_misc_memhint_neon (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ unsigned int op1 = bits (insn, 20, 26), op2 = bits (insn, 4, 7);
+ unsigned int rn = bits (insn, 16, 19);
+
+ if (op1 == 0x10 && (op2 & 0x2) == 0x0 && (rn & 0xe) == 0x0)
+ return copy_unmodified (gdbarch, insn, "cps", dsc);
+ else if (op1 == 0x10 && op2 == 0x0 && (rn & 0xe) == 0x1)
+ return copy_unmodified (gdbarch, insn, "setend", dsc);
+ else if ((op1 & 0x60) == 0x20)
+ return copy_unmodified (gdbarch, insn, "neon dataproc", dsc);
+ else if ((op1 & 0x71) == 0x40)
+ return copy_unmodified (gdbarch, insn, "neon elt/struct load/store", dsc);
+ else if ((op1 & 0x77) == 0x41)
+ return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
+ else if ((op1 & 0x77) == 0x45)
+ return copy_preload (gdbarch, insn, regs, dsc); /* pli. */
+ else if ((op1 & 0x77) == 0x51)
+ {
+ if (rn != 0xf)
+ return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
+ else
+ return copy_unpred (gdbarch, insn, dsc);
+ }
+ else if ((op1 & 0x77) == 0x55)
+ return copy_preload (gdbarch, insn, regs, dsc); /* pld/pldw. */
+ else if (op1 == 0x57)
+ switch (op2)
+ {
+ case 0x1: return copy_unmodified (gdbarch, insn, "clrex", dsc);
+ case 0x4: return copy_unmodified (gdbarch, insn, "dsb", dsc);
+ case 0x5: return copy_unmodified (gdbarch, insn, "dmb", dsc);
+ case 0x6: return copy_unmodified (gdbarch, insn, "isb", dsc);
+ default: return copy_unpred (gdbarch, insn, dsc);
+ }
+ else if ((op1 & 0x63) == 0x43)
+ return copy_unpred (gdbarch, insn, dsc);
+ else if ((op2 & 0x1) == 0x0)
+ switch (op1 & ~0x80)
+ {
+ case 0x61:
+ return copy_unmodified (gdbarch, insn, "unallocated mem hint", dsc);
+ case 0x65:
+ return copy_preload_reg (gdbarch, insn, regs, dsc); /* pli reg. */
+ case 0x71: case 0x75:
+ /* pld/pldw reg. */
+ return copy_preload_reg (gdbarch, insn, regs, dsc);
+ case 0x63: case 0x67: case 0x73: case 0x77:
+ return copy_unpred (gdbarch, insn, dsc);
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+ else
+ return copy_undef (gdbarch, insn, dsc); /* Probably unreachable. */
+}
+
+static int
+decode_unconditional (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 27) == 0)
+ return decode_misc_memhint_neon (gdbarch, insn, regs, dsc);
+ /* Switch on bits: 0bxxxxx321xxx0xxxxxxxxxxxxxxxxxxxx. */
+ else switch (((insn & 0x7000000) >> 23) | ((insn & 0x100000) >> 20))
+ {
+ case 0x0: case 0x2:
+ return copy_unmodified (gdbarch, insn, "srs", dsc);
+
+ case 0x1: case 0x3:
+ return copy_unmodified (gdbarch, insn, "rfe", dsc);
+
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ return copy_b_bl_blx (gdbarch, insn, regs, dsc);
+
+ case 0x8:
+ switch ((insn & 0xe00000) >> 21)
+ {
+ case 0x1: case 0x3: case 0x4: case 0x5: case 0x6: case 0x7:
+ /* stc/stc2. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+
+ case 0x2:
+ return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
+
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+
+ case 0x9:
+ {
+ int rn_f = (bits (insn, 16, 19) == 0xf);
+ switch ((insn & 0xe00000) >> 21)
+ {
+ case 0x1: case 0x3:
+ /* ldc/ldc2 imm (undefined for rn == pc). */
+ return rn_f ? copy_undef (gdbarch, insn, dsc)
+ : copy_copro_load_store (gdbarch, insn, regs, dsc);
+
+ case 0x2:
+ return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
+
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ /* ldc/ldc2 lit (undefined for rn != pc). */
+ return rn_f ? copy_copro_load_store (gdbarch, insn, regs, dsc)
+ : copy_undef (gdbarch, insn, dsc);
+
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+ }
+
+ case 0xa:
+ return copy_unmodified (gdbarch, insn, "stc/stc2", dsc);
+
+ case 0xb:
+ if (bits (insn, 16, 19) == 0xf)
+ /* ldc/ldc2 lit. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0xc:
+ if (bit (insn, 4))
+ return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+
+ case 0xd:
+ if (bit (insn, 4))
+ return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+}
+
+/* Decode miscellaneous instructions in dp/misc encoding space. */
+
+static int
+decode_miscellaneous (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int op2 = bits (insn, 4, 6);
+ unsigned int op = bits (insn, 21, 22);
+ unsigned int op1 = bits (insn, 16, 19);
+
+ switch (op2)
+ {
+ case 0x0:
+ return copy_unmodified (gdbarch, insn, "mrs/msr", dsc);
+
+ case 0x1:
+ if (op == 0x1) /* bx. */
+ return copy_bx_blx_reg (gdbarch, insn, regs, dsc);
+ else if (op == 0x3)
+ return copy_unmodified (gdbarch, insn, "clz", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x2:
+ if (op == 0x1)
+ /* Not really supported. */
+ return copy_unmodified (gdbarch, insn, "bxj", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x3:
+ if (op == 0x1)
+ return copy_bx_blx_reg (gdbarch, insn, regs, dsc); /* blx register. */
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x5:
+ return copy_unmodified (gdbarch, insn, "saturating add/sub", dsc);
+
+ case 0x7:
+ if (op == 0x1)
+ return copy_unmodified (gdbarch, insn, "bkpt", dsc);
+ else if (op == 0x3)
+ /* Not really supported. */
+ return copy_unmodified (gdbarch, insn, "smc", dsc);
+
+ default:
+ return copy_undef (gdbarch, insn, dsc);
+ }
+}
+
+static int
+decode_dp_misc (struct gdbarch *gdbarch, uint32_t insn, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 25))
+ switch (bits (insn, 20, 24))
+ {
+ case 0x10:
+ return copy_unmodified (gdbarch, insn, "movw", dsc);
+
+ case 0x14:
+ return copy_unmodified (gdbarch, insn, "movt", dsc);
+
+ case 0x12: case 0x16:
+ return copy_unmodified (gdbarch, insn, "msr imm", dsc);
+
+ default:
+ return copy_alu_imm (gdbarch, insn, regs, dsc);
+ }
+ else
+ {
+ uint32_t op1 = bits (insn, 20, 24), op2 = bits (insn, 4, 7);
+
+ if ((op1 & 0x19) != 0x10 && (op2 & 0x1) == 0x0)
+ return copy_alu_reg (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) != 0x10 && (op2 & 0x9) == 0x1)
+ return copy_alu_shifted_reg (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) == 0x10 && (op2 & 0x8) == 0x0)
+ return decode_miscellaneous (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x19) == 0x10 && (op2 & 0x9) == 0x8)
+ return copy_unmodified (gdbarch, insn, "halfword mul/mla", dsc);
+ else if ((op1 & 0x10) == 0x00 && op2 == 0x9)
+ return copy_unmodified (gdbarch, insn, "mul/mla", dsc);
+ else if ((op1 & 0x10) == 0x10 && op2 == 0x9)
+ return copy_unmodified (gdbarch, insn, "synch", dsc);
+ else if (op2 == 0xb || (op2 & 0xd) == 0xd)
+ /* 2nd arg means "unpriveleged". */
+ return copy_extra_ld_st (gdbarch, insn, (op1 & 0x12) == 0x02, regs,
+ dsc);
+ }
+
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+decode_ld_st_word_ubyte (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int a = bit (insn, 25), b = bit (insn, 4);
+ uint32_t op1 = bits (insn, 20, 24);
+ int rn_f = bits (insn, 16, 19) == 0xf;
+
+ if ((!a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02)
+ || (a && (op1 & 0x05) == 0x00 && (op1 & 0x17) != 0x02 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 0);
+ else if ((!a && (op1 & 0x17) == 0x02)
+ || (a && (op1 & 0x17) == 0x02 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 0, 1);
+ else if ((!a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03)
+ || (a && (op1 & 0x05) == 0x01 && (op1 & 0x17) != 0x03 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 0);
+ else if ((!a && (op1 & 0x17) == 0x03)
+ || (a && (op1 & 0x17) == 0x03 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 0, 1);
+ else if ((!a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06)
+ || (a && (op1 & 0x05) == 0x04 && (op1 & 0x17) != 0x06 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 0);
+ else if ((!a && (op1 & 0x17) == 0x06)
+ || (a && (op1 & 0x17) == 0x06 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 0, 1, 1);
+ else if ((!a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07)
+ || (a && (op1 & 0x05) == 0x05 && (op1 & 0x17) != 0x07 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 0);
+ else if ((!a && (op1 & 0x17) == 0x07)
+ || (a && (op1 & 0x17) == 0x07 && !b))
+ return copy_ldr_str_ldrb_strb (gdbarch, insn, regs, dsc, 1, 1, 1);
+
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+decode_media (struct gdbarch *gdbarch, uint32_t insn,
+ struct displaced_step_closure *dsc)
+{
+ switch (bits (insn, 20, 24))
+ {
+ case 0x00: case 0x01: case 0x02: case 0x03:
+ return copy_unmodified (gdbarch, insn, "parallel add/sub signed", dsc);
+
+ case 0x04: case 0x05: case 0x06: case 0x07:
+ return copy_unmodified (gdbarch, insn, "parallel add/sub unsigned", dsc);
+
+ case 0x08: case 0x09: case 0x0a: case 0x0b:
+ case 0x0c: case 0x0d: case 0x0e: case 0x0f:
+ return copy_unmodified (gdbarch, insn,
+ "decode/pack/unpack/saturate/reverse", dsc);
+
+ case 0x18:
+ if (bits (insn, 5, 7) == 0) /* op2. */
+ {
+ if (bits (insn, 12, 15) == 0xf)
+ return copy_unmodified (gdbarch, insn, "usad8", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "usada8", dsc);
+ }
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x1a: case 0x1b:
+ if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
+ return copy_unmodified (gdbarch, insn, "sbfx", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x1c: case 0x1d:
+ if (bits (insn, 5, 6) == 0x0) /* op2[1:0]. */
+ {
+ if (bits (insn, 0, 3) == 0xf)
+ return copy_unmodified (gdbarch, insn, "bfc", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "bfi", dsc);
+ }
+ else
+ return copy_undef (gdbarch, insn, dsc);
+
+ case 0x1e: case 0x1f:
+ if (bits (insn, 5, 6) == 0x2) /* op2[1:0]. */
+ return copy_unmodified (gdbarch, insn, "ubfx", dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc);
+ }
+
+ /* Should be unreachable. */
+ return 1;
+}
+
+static int
+decode_b_bl_ldmstm (struct gdbarch *gdbarch, int32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ if (bit (insn, 25))
+ return copy_b_bl_blx (gdbarch, insn, regs, dsc);
+ else
+ return copy_block_xfer (gdbarch, insn, regs, dsc);
+}
+
+static int
+decode_ext_reg_ld_st (struct gdbarch *gdbarch, uint32_t insn,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int opcode = bits (insn, 20, 24);
+
+ switch (opcode)
+ {
+ case 0x04: case 0x05: /* VFP/Neon mrrc/mcrr. */
+ return copy_unmodified (gdbarch, insn, "vfp/neon mrrc/mcrr", dsc);
+
+ case 0x08: case 0x0a: case 0x0c: case 0x0e:
+ case 0x12: case 0x16:
+ return copy_unmodified (gdbarch, insn, "vfp/neon vstm/vpush", dsc);
+
+ case 0x09: case 0x0b: case 0x0d: case 0x0f:
+ case 0x13: case 0x17:
+ return copy_unmodified (gdbarch, insn, "vfp/neon vldm/vpop", dsc);
+
+ case 0x10: case 0x14: case 0x18: case 0x1c: /* vstr. */
+ case 0x11: case 0x15: case 0x19: case 0x1d: /* vldr. */
+ /* Note: no writeback for these instructions. Bit 25 will always be
+ zero though (via caller), so the following works OK. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ }
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
+ /* Should be unreachable. */
+ return 1;
+}
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- }
- }
- break;
+static int
+decode_svc_copro (struct gdbarch *gdbarch, uint32_t insn, CORE_ADDR to,
+ struct regcache *regs, struct displaced_step_closure *dsc)
+{
+ unsigned int op1 = bits (insn, 20, 25);
+ int op = bit (insn, 4);
+ unsigned int coproc = bits (insn, 8, 11);
+ unsigned int rn = bits (insn, 16, 19);
+
+ if ((op1 & 0x20) == 0x00 && (op1 & 0x3a) != 0x00 && (coproc & 0xe) == 0xa)
+ return decode_ext_reg_ld_st (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x21) == 0x00 && (op1 & 0x3a) != 0x00
+ && (coproc & 0xe) != 0xa)
+ /* stc/stc2. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x21) == 0x01 && (op1 & 0x3a) != 0x00
+ && (coproc & 0xe) != 0xa)
+ /* ldc/ldc2 imm/lit. */
+ return copy_copro_load_store (gdbarch, insn, regs, dsc);
+ else if ((op1 & 0x3e) == 0x00)
+ return copy_undef (gdbarch, insn, dsc);
+ else if ((op1 & 0x3e) == 0x04 && (coproc & 0xe) == 0xa)
+ return copy_unmodified (gdbarch, insn, "neon 64bit xfer", dsc);
+ else if (op1 == 0x04 && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mcrr/mcrr2", dsc);
+ else if (op1 == 0x05 && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mrrc/mrrc2", dsc);
+ else if ((op1 & 0x30) == 0x20 && !op)
+ {
+ if ((coproc & 0xe) == 0xa)
+ return copy_unmodified (gdbarch, insn, "vfp dataproc", dsc);
+ else
+ return copy_unmodified (gdbarch, insn, "cdp/cdp2", dsc);
+ }
+ else if ((op1 & 0x30) == 0x20 && op)
+ return copy_unmodified (gdbarch, insn, "neon 8/16/32 bit xfer", dsc);
+ else if ((op1 & 0x31) == 0x20 && op && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mcr/mcr2", dsc);
+ else if ((op1 & 0x31) == 0x21 && op && (coproc & 0xe) != 0xa)
+ return copy_unmodified (gdbarch, insn, "mrc/mrc2", dsc);
+ else if ((op1 & 0x30) == 0x30)
+ return copy_svc (gdbarch, insn, to, regs, dsc);
+ else
+ return copy_undef (gdbarch, insn, dsc); /* Possibly unreachable. */
+}
- case 0x8:
- case 0x9: /* block transfer */
- if (bit (this_instr, 20))
- {
- /* LDM */
- if (bit (this_instr, 15))
- {
- /* loading pc */
- int offset = 0;
+void
+arm_process_displaced_insn (struct gdbarch *gdbarch, uint32_t insn,
+ CORE_ADDR from, CORE_ADDR to, struct regcache *regs,
+ struct displaced_step_closure *dsc)
+{
+ int err = 0;
+
+ if (!displaced_in_arm_mode (regs))
+ error (_("Displaced stepping is only supported in ARM mode"));
+
+ /* Most displaced instructions use a 1-instruction scratch space, so set this
+ here and override below if/when necessary. */
+ dsc->numinsns = 1;
+ dsc->insn_addr = from;
+ dsc->scratch_base = to;
+ dsc->cleanup = NULL;
+ dsc->wrote_to_pc = 0;
+
+ if ((insn & 0xf0000000) == 0xf0000000)
+ err = decode_unconditional (gdbarch, insn, regs, dsc);
+ else switch (((insn & 0x10) >> 4) | ((insn & 0xe000000) >> 24))
+ {
+ case 0x0: case 0x1: case 0x2: case 0x3:
+ err = decode_dp_misc (gdbarch, insn, regs, dsc);
+ break;
- if (bit (this_instr, 23))
- {
- /* up */
- unsigned long reglist = bits (this_instr, 0, 14);
- offset = bitcount (reglist) * 4;
- if (bit (this_instr, 24)) /* pre */
- offset += 4;
- }
- else if (bit (this_instr, 24))
- offset = -4;
+ case 0x4: case 0x5: case 0x6:
+ err = decode_ld_st_word_ubyte (gdbarch, insn, regs, dsc);
+ break;
- {
- unsigned long rn_val =
- get_frame_register_unsigned (frame,
- bits (this_instr, 16, 19));
- nextpc =
- (CORE_ADDR) read_memory_integer ((CORE_ADDR) (rn_val
- + offset),
- 4);
- }
- nextpc = gdbarch_addr_bits_remove
- (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- }
- }
- break;
+ case 0x7:
+ err = decode_media (gdbarch, insn, dsc);
+ break;
- case 0xb: /* branch & link */
- case 0xa: /* branch */
- {
- nextpc = BranchDest (pc, this_instr);
+ case 0x8: case 0x9: case 0xa: case 0xb:
+ err = decode_b_bl_ldmstm (gdbarch, insn, regs, dsc);
+ break;
- nextpc = gdbarch_addr_bits_remove (gdbarch, nextpc);
- if (nextpc == pc)
- error (_("Infinite loop detected"));
- break;
- }
+ case 0xc: case 0xd: case 0xe: case 0xf:
+ err = decode_svc_copro (gdbarch, insn, to, regs, dsc);
+ break;
+ }
- case 0xc:
- case 0xd:
- case 0xe: /* coproc ops */
- case 0xf: /* SWI */
- break;
+ if (err)
+ internal_error (__FILE__, __LINE__,
+ _("arm_process_displaced_insn: Instruction decode error"));
+}
- default:
- fprintf_filtered (gdb_stderr, _("Bad bit-field extraction\n"));
- return (pc);
- }
+/* Actually set up the scratch space for a displaced instruction. */
+
+void
+arm_displaced_init_closure (struct gdbarch *gdbarch, CORE_ADDR from,
+ CORE_ADDR to, struct displaced_step_closure *dsc)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ unsigned int i;
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+
+ /* Poke modified instruction(s). */
+ for (i = 0; i < dsc->numinsns; i++)
+ {
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: writing insn %.8lx at "
+ "%.8lx\n", (unsigned long) dsc->modinsn[i],
+ (unsigned long) to + i * 4);
+ write_memory_unsigned_integer (to + i * 4, 4, byte_order_for_code,
+ dsc->modinsn[i]);
}
- return nextpc;
+ /* Put breakpoint afterwards. */
+ write_memory (to + dsc->numinsns * 4, tdep->arm_breakpoint,
+ tdep->arm_breakpoint_size);
+
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: copy %s->%s: ",
+ paddress (gdbarch, from), paddress (gdbarch, to));
}
-/* single_step() is called just before we want to resume the inferior,
- if we want to single-step it but there is no hardware or kernel
- single-step support. We find the target of the coming instruction
- and breakpoint it. */
+/* Entry point for copying an instruction into scratch space for displaced
+ stepping. */
-int
-arm_software_single_step (struct frame_info *frame)
+struct displaced_step_closure *
+arm_displaced_step_copy_insn (struct gdbarch *gdbarch,
+ CORE_ADDR from, CORE_ADDR to,
+ struct regcache *regs)
{
- /* NOTE: This may insert the wrong breakpoint instruction when
- single-stepping over a mode-changing instruction, if the
- CPSR heuristics are used. */
+ struct displaced_step_closure *dsc
+ = xmalloc (sizeof (struct displaced_step_closure));
+ enum bfd_endian byte_order_for_code = gdbarch_byte_order_for_code (gdbarch);
+ uint32_t insn = read_memory_unsigned_integer (from, 4, byte_order_for_code);
- CORE_ADDR next_pc = arm_get_next_pc (frame, get_frame_pc (frame));
- insert_single_step_breakpoint (next_pc);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog, "displaced: stepping insn %.8lx "
+ "at %.8lx\n", (unsigned long) insn,
+ (unsigned long) from);
- return 1;
+ arm_process_displaced_insn (gdbarch, insn, from, to, regs, dsc);
+ arm_displaced_init_closure (gdbarch, from, to, dsc);
+
+ return dsc;
+}
+
+/* Entry point for cleaning things up after a displaced instruction has been
+ single-stepped. */
+
+void
+arm_displaced_step_fixup (struct gdbarch *gdbarch,
+ struct displaced_step_closure *dsc,
+ CORE_ADDR from, CORE_ADDR to,
+ struct regcache *regs)
+{
+ if (dsc->cleanup)
+ dsc->cleanup (gdbarch, regs, dsc);
+
+ if (!dsc->wrote_to_pc)
+ regcache_cooked_write_unsigned (regs, ARM_PC_REGNUM, dsc->insn_addr + 4);
}
#include "bfd-in2.h"
gdb_byte *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regs);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
if (TYPE_CODE_FLT == TYPE_CODE (type))
{
case ARM_FLOAT_SOFT_FPA:
case ARM_FLOAT_SOFT_VFP:
+ /* ARM_FLOAT_VFP can arise if this is a variadic function so
+ not using the VFP ABI code. */
+ case ARM_FLOAT_VFP:
regcache_cooked_read (regs, ARM_A1_REGNUM, valbuf);
if (TYPE_LENGTH (type) > 4)
regcache_cooked_read (regs, ARM_A1_REGNUM + 1,
store_unsigned_integer (valbuf,
(len > INT_REGISTER_SIZE
? INT_REGISTER_SIZE : len),
- tmp);
+ byte_order, tmp);
len -= INT_REGISTER_SIZE;
valbuf += INT_REGISTER_SIZE;
}
const gdb_byte *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regs);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
if (TYPE_CODE (type) == TYPE_CODE_FLT)
{
case ARM_FLOAT_SOFT_FPA:
case ARM_FLOAT_SOFT_VFP:
+ /* ARM_FLOAT_VFP can arise if this is a variadic function so
+ not using the VFP ABI code. */
+ case ARM_FLOAT_VFP:
regcache_cooked_write (regs, ARM_A1_REGNUM, valbuf);
if (TYPE_LENGTH (type) > 4)
regcache_cooked_write (regs, ARM_A1_REGNUM + 1,
bfd_byte tmpbuf[INT_REGISTER_SIZE];
LONGEST val = unpack_long (type, valbuf);
- store_signed_integer (tmpbuf, INT_REGISTER_SIZE, val);
+ store_signed_integer (tmpbuf, INT_REGISTER_SIZE, byte_order, val);
regcache_cooked_write (regs, ARM_A1_REGNUM, tmpbuf);
}
else
gdb_byte *readbuf, const gdb_byte *writebuf)
{
struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum arm_vfp_cprc_base_type vfp_base_type;
+ int vfp_base_count;
+
+ if (arm_vfp_abi_for_function (gdbarch, func_type)
+ && arm_vfp_call_candidate (valtype, &vfp_base_type, &vfp_base_count))
+ {
+ int reg_char = arm_vfp_cprc_reg_char (vfp_base_type);
+ int unit_length = arm_vfp_cprc_unit_length (vfp_base_type);
+ int i;
+ for (i = 0; i < vfp_base_count; i++)
+ {
+ if (reg_char == 'q')
+ {
+ if (writebuf)
+ arm_neon_quad_write (gdbarch, regcache, i,
+ writebuf + i * unit_length);
+
+ if (readbuf)
+ arm_neon_quad_read (gdbarch, regcache, i,
+ readbuf + i * unit_length);
+ }
+ else
+ {
+ char name_buf[4];
+ int regnum;
+
+ sprintf (name_buf, "%c%d", reg_char, i);
+ regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+ if (writebuf)
+ regcache_cooked_write (regcache, regnum,
+ writebuf + i * unit_length);
+ if (readbuf)
+ regcache_cooked_read (regcache, regnum,
+ readbuf + i * unit_length);
+ }
+ }
+ return RETURN_VALUE_REGISTER_CONVENTION;
+ }
if (TYPE_CODE (valtype) == TYPE_CODE_STRUCT
|| TYPE_CODE (valtype) == TYPE_CODE_UNION
static int
arm_get_longjmp_target (struct frame_info *frame, CORE_ADDR *pc)
{
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR jb_addr;
char buf[INT_REGISTER_SIZE];
- struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (frame));
jb_addr = get_frame_register_unsigned (frame, ARM_A1_REGNUM);
INT_REGISTER_SIZE))
return 0;
- *pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE);
+ *pc = extract_unsigned_integer (buf, INT_REGISTER_SIZE, byte_order);
return 1;
}
/* If PC is in a Thumb call or return stub, return the address of the
target PC, which is in a register. The thunk functions are called
_call_via_xx, where x is the register name. The possible names
- are r0-r9, sl, fp, ip, sp, and lr. */
- if (strncmp (name, "_call_via_", 10) == 0)
+ are r0-r9, sl, fp, ip, sp, and lr. ARM RealView has similar
+ functions, named __ARM_call_via_r[0-7]. */
+ if (strncmp (name, "_call_via_", 10) == 0
+ || strncmp (name, "__ARM_call_via_", strlen ("__ARM_call_via_")) == 0)
{
/* Use the name suffix to determine which register contains the
target PC. */
struct gdbarch_info info;
/* If the current architecture is not ARM, we have nothing to do. */
- if (gdbarch_bfd_arch_info (current_gdbarch)->arch != bfd_arch_arm)
+ if (gdbarch_bfd_arch_info (target_gdbarch)->arch != bfd_arch_arm)
return;
/* Update the architecture. */
show_fp_model (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
- struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
if (arm_fp_model == ARM_FLOAT_AUTO
- && gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
+ && gdbarch_bfd_arch_info (target_gdbarch)->arch == bfd_arch_arm)
fprintf_filtered (file, _("\
The current ARM floating point model is \"auto\" (currently \"%s\").\n"),
fp_model_strings[tdep->fp_model]);
arm_show_abi (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
- struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
if (arm_abi_global == ARM_ABI_AUTO
- && gdbarch_bfd_arch_info (current_gdbarch)->arch == bfd_arch_arm)
+ && gdbarch_bfd_arch_info (target_gdbarch)->arch == bfd_arch_arm)
fprintf_filtered (file, _("\
The current ARM ABI is \"auto\" (currently \"%s\").\n"),
arm_abi_strings[tdep->arm_abi]);
arm_abi_string);
}
+static void
+arm_show_fallback_mode (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
+
+ fprintf_filtered (file, _("\
+The current execution mode assumed (when symbols are unavailable) is \"%s\".\n"),
+ arm_fallback_mode_string);
+}
+
+static void
+arm_show_force_mode (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (target_gdbarch);
+
+ fprintf_filtered (file, _("\
+The current execution mode assumed (even when symbols are available) is \"%s\".\n"),
+ arm_force_mode_string);
+}
+
/* If the user changes the register disassembly style used for info
register and other commands, we have to also switch the style used
in opcodes for disassembly output. This function is run in the "set
static const char *
arm_register_name (struct gdbarch *gdbarch, int i)
{
+ const int num_regs = gdbarch_num_regs (gdbarch);
+
+ if (gdbarch_tdep (gdbarch)->have_vfp_pseudos
+ && i >= num_regs && i < num_regs + 32)
+ {
+ static const char *const vfp_pseudo_names[] = {
+ "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
+ "s8", "s9", "s10", "s11", "s12", "s13", "s14", "s15",
+ "s16", "s17", "s18", "s19", "s20", "s21", "s22", "s23",
+ "s24", "s25", "s26", "s27", "s28", "s29", "s30", "s31",
+ };
+
+ return vfp_pseudo_names[i - num_regs];
+ }
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos
+ && i >= num_regs + 32 && i < num_regs + 32 + 16)
+ {
+ static const char *const neon_pseudo_names[] = {
+ "q0", "q1", "q2", "q3", "q4", "q5", "q6", "q7",
+ "q8", "q9", "q10", "q11", "q12", "q13", "q14", "q15",
+ };
+
+ return neon_pseudo_names[i - num_regs - 32];
+ }
+
if (i >= ARRAY_SIZE (arm_register_names))
/* These registers are only supported on targets which supply
an XML description. */
static int
coff_sym_is_thumb (int val)
{
- return (val == C_THUMBEXT ||
- val == C_THUMBSTAT ||
- val == C_THUMBEXTFUNC ||
- val == C_THUMBSTATFUNC ||
- val == C_THUMBLABEL);
+ return (val == C_THUMBEXT
+ || val == C_THUMBSTAT
+ || val == C_THUMBEXTFUNC
+ || val == C_THUMBSTATFUNC
+ || val == C_THUMBLABEL);
}
/* arm_coff_make_msymbol_special()
}
static void
+arm_objfile_data_free (struct objfile *objfile, void *arg)
+{
+ struct arm_per_objfile *data = arg;
+ unsigned int i;
+
+ for (i = 0; i < objfile->obfd->section_count; i++)
+ VEC_free (arm_mapping_symbol_s, data->section_maps[i]);
+}
+
+static void
+arm_record_special_symbol (struct gdbarch *gdbarch, struct objfile *objfile,
+ asymbol *sym)
+{
+ const char *name = bfd_asymbol_name (sym);
+ struct arm_per_objfile *data;
+ VEC(arm_mapping_symbol_s) **map_p;
+ struct arm_mapping_symbol new_map_sym;
+
+ gdb_assert (name[0] == '$');
+ if (name[1] != 'a' && name[1] != 't' && name[1] != 'd')
+ return;
+
+ data = objfile_data (objfile, arm_objfile_data_key);
+ if (data == NULL)
+ {
+ data = OBSTACK_ZALLOC (&objfile->objfile_obstack,
+ struct arm_per_objfile);
+ set_objfile_data (objfile, arm_objfile_data_key, data);
+ data->section_maps = OBSTACK_CALLOC (&objfile->objfile_obstack,
+ objfile->obfd->section_count,
+ VEC(arm_mapping_symbol_s) *);
+ }
+ map_p = &data->section_maps[bfd_get_section (sym)->index];
+
+ new_map_sym.value = sym->value;
+ new_map_sym.type = name[1];
+
+ /* Assume that most mapping symbols appear in order of increasing
+ value. If they were randomly distributed, it would be faster to
+ always push here and then sort at first use. */
+ if (!VEC_empty (arm_mapping_symbol_s, *map_p))
+ {
+ struct arm_mapping_symbol *prev_map_sym;
+
+ prev_map_sym = VEC_last (arm_mapping_symbol_s, *map_p);
+ if (prev_map_sym->value >= sym->value)
+ {
+ unsigned int idx;
+ idx = VEC_lower_bound (arm_mapping_symbol_s, *map_p, &new_map_sym,
+ arm_compare_mapping_symbols);
+ VEC_safe_insert (arm_mapping_symbol_s, *map_p, idx, &new_map_sym);
+ return;
+ }
+ }
+
+ VEC_safe_push (arm_mapping_symbol_s, *map_p, &new_map_sym);
+}
+
+static void
arm_write_pc (struct regcache *regcache, CORE_ADDR pc)
{
regcache_cooked_write_unsigned (regcache, ARM_PC_REGNUM, pc);
}
}
+/* Read the contents of a NEON quad register, by reading from two
+ double registers. This is used to implement the quad pseudo
+ registers, and for argument passing in case the quad registers are
+ missing; vectors are passed in quad registers when using the VFP
+ ABI, even if a NEON unit is not present. REGNUM is the index of
+ the quad register, in [0, 15]. */
+
+static void
+arm_neon_quad_read (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, gdb_byte *buf)
+{
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ sprintf (name_buf, "d%d", regnum << 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ /* d0 is always the least significant half of q0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = 8;
+ else
+ offset = 0;
+
+ regcache_raw_read (regcache, double_regnum, reg_buf);
+ memcpy (buf + offset, reg_buf, 8);
+
+ offset = 8 - offset;
+ regcache_raw_read (regcache, double_regnum + 1, reg_buf);
+ memcpy (buf + offset, reg_buf, 8);
+}
+
+static void
+arm_pseudo_read (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, gdb_byte *buf)
+{
+ const int num_regs = gdbarch_num_regs (gdbarch);
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ gdb_assert (regnum >= num_regs);
+ regnum -= num_regs;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48)
+ /* Quad-precision register. */
+ arm_neon_quad_read (gdbarch, regcache, regnum - 32, buf);
+ else
+ {
+ /* Single-precision register. */
+ gdb_assert (regnum < 32);
+
+ /* s0 is always the least significant half of d0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = (regnum & 1) ? 0 : 4;
+ else
+ offset = (regnum & 1) ? 4 : 0;
+
+ sprintf (name_buf, "d%d", regnum >> 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ regcache_raw_read (regcache, double_regnum, reg_buf);
+ memcpy (buf, reg_buf + offset, 4);
+ }
+}
+
+/* Store the contents of BUF to a NEON quad register, by writing to
+ two double registers. This is used to implement the quad pseudo
+ registers, and for argument passing in case the quad registers are
+ missing; vectors are passed in quad registers when using the VFP
+ ABI, even if a NEON unit is not present. REGNUM is the index
+ of the quad register, in [0, 15]. */
+
+static void
+arm_neon_quad_write (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, const gdb_byte *buf)
+{
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ sprintf (name_buf, "d%d", regnum << 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ /* d0 is always the least significant half of q0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = 8;
+ else
+ offset = 0;
+
+ regcache_raw_write (regcache, double_regnum, buf + offset);
+ offset = 8 - offset;
+ regcache_raw_write (regcache, double_regnum + 1, buf + offset);
+}
+
+static void
+arm_pseudo_write (struct gdbarch *gdbarch, struct regcache *regcache,
+ int regnum, const gdb_byte *buf)
+{
+ const int num_regs = gdbarch_num_regs (gdbarch);
+ char name_buf[4];
+ gdb_byte reg_buf[8];
+ int offset, double_regnum;
+
+ gdb_assert (regnum >= num_regs);
+ regnum -= num_regs;
+
+ if (gdbarch_tdep (gdbarch)->have_neon_pseudos && regnum >= 32 && regnum < 48)
+ /* Quad-precision register. */
+ arm_neon_quad_write (gdbarch, regcache, regnum - 32, buf);
+ else
+ {
+ /* Single-precision register. */
+ gdb_assert (regnum < 32);
+
+ /* s0 is always the least significant half of d0. */
+ if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
+ offset = (regnum & 1) ? 0 : 4;
+ else
+ offset = (regnum & 1) ? 4 : 0;
+
+ sprintf (name_buf, "d%d", regnum >> 1);
+ double_regnum = user_reg_map_name_to_regnum (gdbarch, name_buf,
+ strlen (name_buf));
+
+ regcache_raw_read (regcache, double_regnum, reg_buf);
+ memcpy (reg_buf + offset, buf, 4);
+ regcache_raw_write (regcache, double_regnum, reg_buf);
+ }
+}
+
static struct value *
value_of_arm_user_reg (struct frame_info *frame, const void *baton)
{
enum arm_float_model fp_model = arm_fp_model;
struct tdesc_arch_data *tdesc_data = NULL;
int i;
+ int have_vfp_registers = 0, have_vfp_pseudos = 0, have_neon_pseudos = 0;
+ int have_neon = 0;
int have_fpa_registers = 1;
/* Check any target description for validity. */
static const char *const arm_pc_names[] = { "r15", "pc", NULL };
const struct tdesc_feature *feature;
- int i, valid_p;
+ int valid_p;
feature = tdesc_find_feature (info.target_desc,
"org.gnu.gdb.arm.core");
return NULL;
}
}
+
+ /* If we have a VFP unit, check whether the single precision registers
+ are present. If not, then we will synthesize them as pseudo
+ registers. */
+ feature = tdesc_find_feature (info.target_desc,
+ "org.gnu.gdb.arm.vfp");
+ if (feature != NULL)
+ {
+ static const char *const vfp_double_names[] = {
+ "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",
+ "d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15",
+ "d16", "d17", "d18", "d19", "d20", "d21", "d22", "d23",
+ "d24", "d25", "d26", "d27", "d28", "d29", "d30", "d31",
+ };
+
+ /* Require the double precision registers. There must be either
+ 16 or 32. */
+ valid_p = 1;
+ for (i = 0; i < 32; i++)
+ {
+ valid_p &= tdesc_numbered_register (feature, tdesc_data,
+ ARM_D0_REGNUM + i,
+ vfp_double_names[i]);
+ if (!valid_p)
+ break;
+ }
+
+ if (!valid_p && i != 16)
+ {
+ tdesc_data_cleanup (tdesc_data);
+ return NULL;
+ }
+
+ if (tdesc_unnumbered_register (feature, "s0") == 0)
+ have_vfp_pseudos = 1;
+
+ have_vfp_registers = 1;
+
+ /* If we have VFP, also check for NEON. The architecture allows
+ NEON without VFP (integer vector operations only), but GDB
+ does not support that. */
+ feature = tdesc_find_feature (info.target_desc,
+ "org.gnu.gdb.arm.neon");
+ if (feature != NULL)
+ {
+ /* NEON requires 32 double-precision registers. */
+ if (i != 32)
+ {
+ tdesc_data_cleanup (tdesc_data);
+ return NULL;
+ }
+
+ /* If there are quad registers defined by the stub, use
+ their type; otherwise (normally) provide them with
+ the default type. */
+ if (tdesc_unnumbered_register (feature, "q0") == 0)
+ have_neon_pseudos = 1;
+
+ have_neon = 1;
+ }
+ }
}
/* If we have an object to base this architecture on, try to determine
case EF_ARM_EABI_VER4:
case EF_ARM_EABI_VER5:
arm_abi = ARM_ABI_AAPCS;
- /* EABI binaries default to VFP float ordering. */
+ /* EABI binaries default to VFP float ordering.
+ They may also contain build attributes that can
+ be used to identify if the VFP argument-passing
+ ABI is in use. */
if (fp_model == ARM_FLOAT_AUTO)
- fp_model = ARM_FLOAT_SOFT_VFP;
+ {
+#ifdef HAVE_ELF
+ switch (bfd_elf_get_obj_attr_int (info.abfd,
+ OBJ_ATTR_PROC,
+ Tag_ABI_VFP_args))
+ {
+ case 0:
+ /* "The user intended FP parameter/result
+ passing to conform to AAPCS, base
+ variant". */
+ fp_model = ARM_FLOAT_SOFT_VFP;
+ break;
+ case 1:
+ /* "The user intended FP parameter/result
+ passing to conform to AAPCS, VFP
+ variant". */
+ fp_model = ARM_FLOAT_VFP;
+ break;
+ case 2:
+ /* "The user intended FP parameter/result
+ passing to conform to tool chain-specific
+ conventions" - we don't know any such
+ conventions, so leave it as "auto". */
+ break;
+ default:
+ /* Attribute value not mentioned in the
+ October 2008 ABI, so leave it as
+ "auto". */
+ break;
+ }
+#else
+ fp_model = ARM_FLOAT_SOFT_VFP;
+#endif
+ }
break;
default:
break;
}
}
+
+ if (e_flags & EF_ARM_BE8)
+ info.byte_order_for_code = BFD_ENDIAN_LITTLE;
+
break;
default:
&& fp_model != gdbarch_tdep (best_arch->gdbarch)->fp_model)
continue;
+ /* There are various other properties in tdep that we do not
+ need to check here: those derived from a target description,
+ since gdbarches with a different target description are
+ automatically disqualified. */
+
/* Found a match. */
break;
}
tdep->arm_abi = arm_abi;
tdep->fp_model = fp_model;
tdep->have_fpa_registers = have_fpa_registers;
+ tdep->have_vfp_registers = have_vfp_registers;
+ tdep->have_vfp_pseudos = have_vfp_pseudos;
+ tdep->have_neon_pseudos = have_neon_pseudos;
+ tdep->have_neon = have_neon;
/* Breakpoints. */
- switch (info.byte_order)
+ switch (info.byte_order_for_code)
{
case BFD_ENDIAN_BIG:
tdep->arm_breakpoint = arm_default_arm_be_breakpoint;
/* On ARM targets char defaults to unsigned. */
set_gdbarch_char_signed (gdbarch, 0);
+ /* Note: for displaced stepping, this includes the breakpoint, and one word
+ of additional scratch space. This setting isn't used for anything beside
+ displaced stepping at present. */
+ set_gdbarch_max_insn_length (gdbarch, 4 * DISPLACED_MODIFIED_INSNS);
+
/* This should be low enough for everything. */
tdep->lowest_pc = 0x20;
tdep->jb_pc = -1; /* Longjump support not enabled by default. */
set_gdbarch_print_float_info (gdbarch, arm_print_float_info);
/* Internal <-> external register number maps. */
- set_gdbarch_dwarf_reg_to_regnum (gdbarch, arm_dwarf_reg_to_regnum);
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, arm_dwarf_reg_to_regnum);
set_gdbarch_register_sim_regno (gdbarch, arm_register_sim_regno);
set_gdbarch_elf_make_msymbol_special (gdbarch, arm_elf_make_msymbol_special);
set_gdbarch_coff_make_msymbol_special (gdbarch,
arm_coff_make_msymbol_special);
+ set_gdbarch_record_special_symbol (gdbarch, arm_record_special_symbol);
/* Virtual tables. */
set_gdbarch_vbit_in_delta (gdbarch, 1);
set_gdbarch_long_double_format (gdbarch, floatformats_ieee_double);
}
+ if (have_vfp_pseudos)
+ {
+ /* NOTE: These are the only pseudo registers used by
+ the ARM target at the moment. If more are added, a
+ little more care in numbering will be needed. */
+
+ int num_pseudos = 32;
+ if (have_neon_pseudos)
+ num_pseudos += 16;
+ set_gdbarch_num_pseudo_regs (gdbarch, num_pseudos);
+ set_gdbarch_pseudo_register_read (gdbarch, arm_pseudo_read);
+ set_gdbarch_pseudo_register_write (gdbarch, arm_pseudo_write);
+ }
+
if (tdesc_data)
- tdesc_use_registers (gdbarch, info.target_desc, tdesc_data);
+ {
+ set_tdesc_pseudo_register_name (gdbarch, arm_register_name);
+
+ tdesc_use_registers (gdbarch, info.target_desc, tdesc_data);
+
+ /* Override tdesc_register_type to adjust the types of VFP
+ registers for NEON. */
+ set_gdbarch_register_type (gdbarch, arm_register_type);
+ }
/* Add standard register aliases. We add aliases even for those
nanes which are used by the current architecture - it's simpler,
gdbarch_register (bfd_arch_arm, arm_gdbarch_init, arm_dump_tdep);
+ arm_objfile_data_key
+ = register_objfile_data_with_cleanup (NULL, arm_objfile_data_free);
+
/* Register an ELF OS ABI sniffer for ARM binaries. */
gdbarch_register_osabi_sniffer (bfd_arch_arm,
bfd_target_elf_flavour,
_("The valid values are:\n"),
regdesc,
_("The default is \"std\"."));
- helptext = ui_file_xstrdup (stb, &length);
+ helptext = ui_file_xstrdup (stb, NULL);
ui_file_delete (stb);
add_setshow_enum_cmd("disassembler", no_class,
NULL, arm_set_abi, arm_show_abi,
&setarmcmdlist, &showarmcmdlist);
+ /* Add two commands to allow the user to force the assumed
+ execution mode. */
+ add_setshow_enum_cmd ("fallback-mode", class_support,
+ arm_mode_strings, &arm_fallback_mode_string,
+ _("Set the mode assumed when symbols are unavailable."),
+ _("Show the mode assumed when symbols are unavailable."),
+ NULL, NULL, arm_show_fallback_mode,
+ &setarmcmdlist, &showarmcmdlist);
+ add_setshow_enum_cmd ("force-mode", class_support,
+ arm_mode_strings, &arm_force_mode_string,
+ _("Set the mode assumed even when symbols are available."),
+ _("Show the mode assumed even when symbols are available."),
+ NULL, NULL, arm_show_force_mode,
+ &setarmcmdlist, &showarmcmdlist);
+
/* Debugging flag. */
add_setshow_boolean_cmd ("arm", class_maintenance, &arm_debug,
_("Set ARM debugging."),