Update debugbreak for support PowerPC target.

--HG--
branch : release
This commit is contained in:
Roman Telezhynskyi 2018-12-18 16:08:14 +02:00
parent 940d0be073
commit 0da3f9c110

View File

@ -1,4 +1,4 @@
/* Copyright (c) 2011-2015, Scott Tsai /* Copyright (c) 2011-2018, Scott Tsai
* *
* All rights reserved. * All rights reserved.
* *
@ -33,27 +33,22 @@
#else #else
#include <signal.h>
#ifdef __cplusplus #ifdef __cplusplus
extern "C" { extern "C" {
#endif #endif
enum { #define DEBUG_BREAK_USE_TRAP_INSTRUCTION 1
/* gcc optimizers consider code after __builtin_trap() dead. #define DEBUG_BREAK_USE_BULTIN_TRAP 2
* Making __builtin_trap() unsuitable for breaking into the debugger */ #define DEBUG_BREAK_USE_SIGTRAP 3
DEBUG_BREAK_PREFER_BUILTIN_TRAP_TO_SIGTRAP = 0
};
#if defined(__i386__) || defined(__x86_64__) #if defined(__i386__) || defined(__x86_64__)
enum { HAVE_TRAP_INSTRUCTION = 1 }; #define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_TRAP_INSTRUCTION
__attribute__((gnu_inline, always_inline))
__inline__ static void trap_instruction(void) __inline__ static void trap_instruction(void)
{ {
__asm__ volatile("int $0x03"); __asm__ volatile("int $0x03");
} }
#elif defined(__thumb__) #elif defined(__thumb__)
enum { HAVE_TRAP_INSTRUCTION = 1, }; #define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_TRAP_INSTRUCTION
/* FIXME: handle __THUMB_INTERWORK__ */ /* FIXME: handle __THUMB_INTERWORK__ */
__attribute__((gnu_inline, always_inline)) __attribute__((gnu_inline, always_inline))
__inline__ static void trap_instruction(void) __inline__ static void trap_instruction(void)
@ -69,30 +64,37 @@ __inline__ static void trap_instruction(void)
#endif #endif
/* Known problem: /* Known problem:
* After a breakpoint hit, can't stepi, step, or continue in GDB. * After a breakpoint hit, can't 'stepi', 'step', or 'continue' in GDB.
* 'step' stuck on the same instruction. * 'step' would keep getting stuck on the same instruction.
* *
* Workaround: a new GDB command, * Workaround: use the new GDB commands 'debugbreak-step' and
* 'debugbreak-step' is defined in debugbreak-gdb.py * 'debugbreak-continue' that become available
* that does: * after you source the script from GDB:
*
* $ gdb -x debugbreak-gdb.py <... USUAL ARGUMENTS ...>
*
* 'debugbreak-step' would jump over the breakpoint instruction with
* roughly equivalent of:
* (gdb) set $instruction_len = 2 * (gdb) set $instruction_len = 2
* (gdb) tbreak *($pc + $instruction_len) * (gdb) tbreak *($pc + $instruction_len)
* (gdb) jump *($pc + $instruction_len) * (gdb) jump *($pc + $instruction_len)
*/ */
} }
#elif defined(__arm__) && !defined(__thumb__) #elif defined(__arm__) && !defined(__thumb__)
enum { HAVE_TRAP_INSTRUCTION = 1 }; #define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_TRAP_INSTRUCTION
__attribute__((gnu_inline, always_inline)) __attribute__((gnu_inline, always_inline))
__inline__ static void trap_instruction(void) __inline__ static void trap_instruction(void)
{ {
/* See 'arm-linux-tdep.c' in GDB source, /* See 'arm-linux-tdep.c' in GDB source,
* 'eabi_linux_arm_le_breakpoint' */ * 'eabi_linux_arm_le_breakpoint' */
__asm__ volatile(".inst 0xe7f001f0"); __asm__ volatile(".inst 0xe7f001f0");
/* Has same known problem and workaround /* Known problem:
* as Thumb mode */ * Same problem and workaround as Thumb mode */
} }
#elif defined(__aarch64__) && defined(__APPLE__)
#define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_BULTIN_TRAP
#elif defined(__aarch64__) #elif defined(__aarch64__)
enum { HAVE_TRAP_INSTRUCTION = 1 }; #define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_TRAP_INSTRUCTION
__attribute__((gnu_inline, always_inline)) __attribute__((gnu_inline, always_inline))
__inline__ static void trap_instruction(void) __inline__ static void trap_instruction(void)
{ {
@ -100,42 +102,57 @@ __inline__ static void trap_instruction(void)
* 'aarch64_default_breakpoint' */ * 'aarch64_default_breakpoint' */
__asm__ volatile(".inst 0xd4200000"); __asm__ volatile(".inst 0xd4200000");
} }
#elif defined(__powerpc__)
/* PPC 32 or 64-bit, big or little endian */
#define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_TRAP_INSTRUCTION
__attribute__((gnu_inline, always_inline))
__inline__ static void trap_instruction(void)
{
/* See 'rs6000-tdep.c' in GDB source,
* 'rs6000_breakpoint' */
__asm__ volatile(".4byte 0x7d821008");
/* Known problem:
* After a breakpoint hit, can't 'stepi', 'step', or 'continue' in GDB.
* 'step' stuck on the same instruction ("twge r2,r2").
*
* The workaround is the same as ARM Thumb mode: use debugbreak-gdb.py
* or manually jump over the instruction. */
}
#else #else
enum { HAVE_TRAP_INSTRUCTION = 0 }; #define DEBUG_BREAK_IMPL DEBUG_BREAK_USE_SIGTRAP
#endif #endif
#ifndef DEBUG_BREAK_IMPL
#error "debugbreak.h is not supported on this target"
#elif DEBUG_BREAK_IMPL == DEBUG_BREAK_USE_TRAP_INSTRUCTION
__attribute__((gnu_inline, always_inline)) __attribute__((gnu_inline, always_inline))
__inline__ static void debug_break(void) __inline__ static void debug_break(void)
{ {
#if defined(_WIN32) || defined(_WIN64)
/* SIGTRAP available only on POSIX-compliant operating systems
* use builtin trap instead */
HAVE_TRAP_INSTRUCTION ? trap_instruction() : __builtin_trap();
#else
// cppcheck-suppress knownConditionTrueFalse
if (HAVE_TRAP_INSTRUCTION)
{
trap_instruction(); trap_instruction();
}
// cppcheck-suppress knownConditionTrueFalse
else if (DEBUG_BREAK_PREFER_BUILTIN_TRAP_TO_SIGTRAP)
{
/* raises SIGILL on Linux x86{,-64}, to continue in gdb:
* (gdb) handle SIGILL stop nopass
* */
__builtin_trap();
}
else
{
raise(SIGTRAP);
}
#endif
} }
#elif DEBUG_BREAK_IMPL == DEBUG_BREAK_USE_BULTIN_TRAP
__attribute__((gnu_inline, always_inline))
__inline__ static void debug_break(void)
{
__builtin_trap();
}
#elif DEBUG_BREAK_IMPL == DEBUG_BREAK_USE_SIGTRAP
#include <signal.h>
__attribute__((gnu_inline, always_inline))
__inline__ static void debug_break(void)
{
raise(SIGTRAP);
}
#else
#error "invalid DEBUG_BREAK_IMPL value"
#endif
#ifdef __cplusplus #ifdef __cplusplus
} }
#endif #endif
#endif #endif /* ifdef _MSC_VER */
#endif #endif /* ifndef DEBUG_BREAK_H */