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authorRichard Earnshaw <richard.earnshaw@arm.com>2002-02-15 16:12:24 +0000
committerRichard Earnshaw <richard.earnshaw@arm.com>2002-02-15 16:12:24 +0000
commit66e810cd098c57a4483f33cedc272486506eb485 (patch)
tree4f63c94878bbbe7303466f05708c5915015e2c33 /gdb/arm-tdep.c
parent97e03143bb83533b4cf4fcd9d283b05722b4c128 (diff)
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* arm-tdep.h (struct gdbarch_tdep): Add fields for breakpoint
descriptions. * arm-tdep.c (arm_default_arm_le_breakpoint) (arm_default_arm_be_breakpoint, arm_default_thumb_le_breakpoint) (arm_default_thumb_be_breakpoint): New. Initialize them from traditional breakpoint defines. (arm_breakpoint_from_pc): Use new gdbarch_tdep entries. (arm_gdbarch_init): Initialize new breakpoint variables. * arm-linux-tdep.c (arm_linux_arm_le_breakpoint): New. (arm_linux_init_abi): Initialize linux-specific breakpoint. * armnbsd-tdep.c (arm_nbsd_arm_le_breakpoint): New. (arm_netbsd_aout_init_abi, arm_netbsd_elf_init_abi): Split common code out to ... (arm_netbsd_init_abi_common): ... here; new function. * config/arm/tm-arm.h (ARM_LE_BREAKPOINT, ARM_BE_BREAKPOINT) (THUMB_LE_BREAKPOINT, THUMB_BE_BREAKPOINT): Delete. * config/arm/tm-linux.h (ARM_LE_BREAKPOINT): Delete. * config/arm/tm-nbsd.h (ARM_LE_BREAKPOINT): Delete.
Diffstat (limited to 'gdb/arm-tdep.c')
-rw-r--r--gdb/arm-tdep.c97
1 files changed, 70 insertions, 27 deletions
diff --git a/gdb/arm-tdep.c b/gdb/arm-tdep.c
index 9577f0a..a60f497 100644
--- a/gdb/arm-tdep.c
+++ b/gdb/arm-tdep.c
@@ -2044,6 +2044,56 @@ gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info)
return print_insn_little_arm (memaddr, info);
}
+/* The following define instruction sequences that will cause ARM
+ cpu's to take an undefined instruction trap. These are used to
+ signal a breakpoint to GDB.
+
+ The newer ARMv4T cpu's are capable of operating in ARM or Thumb
+ modes. A different instruction is required for each mode. The ARM
+ cpu's can also be big or little endian. Thus four different
+ instructions are needed to support all cases.
+
+ Note: ARMv4 defines several new instructions that will take the
+ undefined instruction trap. ARM7TDMI is nominally ARMv4T, but does
+ not in fact add the new instructions. The new undefined
+ instructions in ARMv4 are all instructions that had no defined
+ behaviour in earlier chips. There is no guarantee that they will
+ raise an exception, but may be treated as NOP's. In practice, it
+ may only safe to rely on instructions matching:
+
+ 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
+ 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+ C C C C 0 1 1 x x x x x x x x x x x x x x x x x x x x 1 x x x x
+
+ Even this may only true if the condition predicate is true. The
+ following use a condition predicate of ALWAYS so it is always TRUE.
+
+ There are other ways of forcing a breakpoint. GNU/Linux, RISC iX,
+ and NetBSD all use a software interrupt rather than an undefined
+ instruction to force a trap. This can be handled by by the
+ abi-specific code during establishment of the gdbarch vector. */
+
+
+/* XXX for now we allow a non-multi-arch gdb to override these
+ definitions. */
+#ifndef ARM_LE_BREAKPOINT
+#define ARM_LE_BREAKPOINT {0xFE,0xDE,0xFF,0xE7}
+#endif
+#ifndef ARM_BE_BREAKPOINT
+#define ARM_BE_BREAKPOINT {0xE7,0xFF,0xDE,0xFE}
+#endif
+#ifndef THUMB_LE_BREAKPOINT
+#define THUMB_LE_BREAKPOINT {0xfe,0xdf}
+#endif
+#ifndef THUMB_BE_BREAKPOINT
+#define THUMB_BE_BREAKPOINT {0xdf,0xfe}
+#endif
+
+static const char arm_default_arm_le_breakpoint[] = ARM_LE_BREAKPOINT;
+static const char arm_default_arm_be_breakpoint[] = ARM_BE_BREAKPOINT;
+static const char arm_default_thumb_le_breakpoint[] = THUMB_LE_BREAKPOINT;
+static const char arm_default_thumb_be_breakpoint[] = THUMB_BE_BREAKPOINT;
+
/* Determine the type and size of breakpoint to insert at PCPTR. Uses
the program counter value to determine whether a 16-bit or 32-bit
breakpoint should be used. It returns a pointer to a string of
@@ -2060,37 +2110,18 @@ gdb_print_insn_arm (bfd_vma memaddr, disassemble_info *info)
unsigned char *
arm_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+
if (arm_pc_is_thumb (*pcptr) || arm_pc_is_thumb_dummy (*pcptr))
{
- if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
- {
- static char thumb_breakpoint[] = THUMB_BE_BREAKPOINT;
- *pcptr = UNMAKE_THUMB_ADDR (*pcptr);
- *lenptr = sizeof (thumb_breakpoint);
- return thumb_breakpoint;
- }
- else
- {
- static char thumb_breakpoint[] = THUMB_LE_BREAKPOINT;
- *pcptr = UNMAKE_THUMB_ADDR (*pcptr);
- *lenptr = sizeof (thumb_breakpoint);
- return thumb_breakpoint;
- }
+ *pcptr = UNMAKE_THUMB_ADDR (*pcptr);
+ *lenptr = tdep->thumb_breakpoint_size;
+ return tdep->thumb_breakpoint;
}
else
{
- if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
- {
- static char arm_breakpoint[] = ARM_BE_BREAKPOINT;
- *lenptr = sizeof (arm_breakpoint);
- return arm_breakpoint;
- }
- else
- {
- static char arm_breakpoint[] = ARM_LE_BREAKPOINT;
- *lenptr = sizeof (arm_breakpoint);
- return arm_breakpoint;
- }
+ *lenptr = tdep->arm_breakpoint_size;
+ return tdep->arm_breakpoint;
}
}
@@ -2710,21 +2741,33 @@ arm_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
tdep->abi_name = "<invalid>";
}
- /* Floating point sizes and format. */
+ /* Breakpoints and floating point sizes and format. */
switch (info.byte_order)
{
case BFD_ENDIAN_BIG:
+ tdep->arm_breakpoint = arm_default_arm_be_breakpoint;
+ tdep->arm_breakpoint_size = sizeof (arm_default_arm_be_breakpoint);
+ tdep->thumb_breakpoint = arm_default_thumb_be_breakpoint;
+ tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_be_breakpoint);
+
set_gdbarch_float_format (gdbarch, &floatformat_ieee_single_big);
set_gdbarch_double_format (gdbarch, &floatformat_ieee_double_big);
set_gdbarch_long_double_format (gdbarch, &floatformat_ieee_double_big);
+
break;
case BFD_ENDIAN_LITTLE:
+ tdep->arm_breakpoint = arm_default_arm_le_breakpoint;
+ tdep->arm_breakpoint_size = sizeof (arm_default_arm_le_breakpoint);
+ tdep->thumb_breakpoint = arm_default_thumb_le_breakpoint;
+ tdep->thumb_breakpoint_size = sizeof (arm_default_thumb_le_breakpoint);
+
set_gdbarch_float_format (gdbarch, &floatformat_ieee_single_little);
set_gdbarch_double_format (gdbarch,
&floatformat_ieee_double_littlebyte_bigword);
set_gdbarch_long_double_format (gdbarch,
&floatformat_ieee_double_littlebyte_bigword);
+
break;
default: