qemu/disas.c
Peter Maydell 636bd28939 disas: Fix printing of addresses in disassembly
In our disassembly code, the bfd_vma type is always 64 bits,
even if the target's virtual address width is only 32 bits. This
means that when we print out addresses we need to truncate them
to 32 bits, to avoid odd output which has incorrectly sign-extended
a value to 64 bits, for instance this ARM example:
    0x80479a60:  e59f4088     ldr  r4, [pc, #136]  ; 0xffffffff80479a4f

(It would also be possible to truncate before passing the address
to info->print_address_func(), but truncating in the final print
function is the same approach that binutils takes to this problem.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2012-07-14 10:32:34 +00:00

473 lines
13 KiB
C

/* General "disassemble this chunk" code. Used for debugging. */
#include "config.h"
#include "dis-asm.h"
#include "elf.h"
#include <errno.h>
#include "cpu.h"
#include "disas.h"
/* Filled in by elfload.c. Simplistic, but will do for now. */
struct syminfo *syminfos = NULL;
/* Get LENGTH bytes from info's buffer, at target address memaddr.
Transfer them to myaddr. */
int
buffer_read_memory(bfd_vma memaddr, bfd_byte *myaddr, int length,
struct disassemble_info *info)
{
if (memaddr < info->buffer_vma
|| memaddr + length > info->buffer_vma + info->buffer_length)
/* Out of bounds. Use EIO because GDB uses it. */
return EIO;
memcpy (myaddr, info->buffer + (memaddr - info->buffer_vma), length);
return 0;
}
/* Get LENGTH bytes from info's buffer, at target address memaddr.
Transfer them to myaddr. */
static int
target_read_memory (bfd_vma memaddr,
bfd_byte *myaddr,
int length,
struct disassemble_info *info)
{
cpu_memory_rw_debug(cpu_single_env, memaddr, myaddr, length, 0);
return 0;
}
/* Print an error message. We can assume that this is in response to
an error return from buffer_read_memory. */
void
perror_memory (int status, bfd_vma memaddr, struct disassemble_info *info)
{
if (status != EIO)
/* Can't happen. */
(*info->fprintf_func) (info->stream, "Unknown error %d\n", status);
else
/* Actually, address between memaddr and memaddr + len was
out of bounds. */
(*info->fprintf_func) (info->stream,
"Address 0x%" PRIx64 " is out of bounds.\n", memaddr);
}
/* This could be in a separate file, to save minuscule amounts of space
in statically linked executables. */
/* Just print the address is hex. This is included for completeness even
though both GDB and objdump provide their own (to print symbolic
addresses). */
void
generic_print_address (bfd_vma addr, struct disassemble_info *info)
{
(*info->fprintf_func) (info->stream, "0x%" PRIx64, addr);
}
/* Print address in hex, truncated to the width of a target virtual address. */
static void
generic_print_target_address(bfd_vma addr, struct disassemble_info *info)
{
uint64_t mask = ~0ULL >> (64 - TARGET_VIRT_ADDR_SPACE_BITS);
generic_print_address(addr & mask, info);
}
/* Print address in hex, truncated to the width of a host virtual address. */
static void
generic_print_host_address(bfd_vma addr, struct disassemble_info *info)
{
uint64_t mask = ~0ULL >> (64 - (sizeof(void *) * 8));
generic_print_address(addr & mask, info);
}
/* Just return the given address. */
int
generic_symbol_at_address (bfd_vma addr, struct disassemble_info *info)
{
return 1;
}
bfd_vma bfd_getl64 (const bfd_byte *addr)
{
unsigned long long v;
v = (unsigned long long) addr[0];
v |= (unsigned long long) addr[1] << 8;
v |= (unsigned long long) addr[2] << 16;
v |= (unsigned long long) addr[3] << 24;
v |= (unsigned long long) addr[4] << 32;
v |= (unsigned long long) addr[5] << 40;
v |= (unsigned long long) addr[6] << 48;
v |= (unsigned long long) addr[7] << 56;
return (bfd_vma) v;
}
bfd_vma bfd_getl32 (const bfd_byte *addr)
{
unsigned long v;
v = (unsigned long) addr[0];
v |= (unsigned long) addr[1] << 8;
v |= (unsigned long) addr[2] << 16;
v |= (unsigned long) addr[3] << 24;
return (bfd_vma) v;
}
bfd_vma bfd_getb32 (const bfd_byte *addr)
{
unsigned long v;
v = (unsigned long) addr[0] << 24;
v |= (unsigned long) addr[1] << 16;
v |= (unsigned long) addr[2] << 8;
v |= (unsigned long) addr[3];
return (bfd_vma) v;
}
bfd_vma bfd_getl16 (const bfd_byte *addr)
{
unsigned long v;
v = (unsigned long) addr[0];
v |= (unsigned long) addr[1] << 8;
return (bfd_vma) v;
}
bfd_vma bfd_getb16 (const bfd_byte *addr)
{
unsigned long v;
v = (unsigned long) addr[0] << 24;
v |= (unsigned long) addr[1] << 16;
return (bfd_vma) v;
}
#ifdef TARGET_ARM
static int
print_insn_thumb1(bfd_vma pc, disassemble_info *info)
{
return print_insn_arm(pc | 1, info);
}
#endif
/* Disassemble this for me please... (debugging). 'flags' has the following
values:
i386 - 1 means 16 bit code, 2 means 64 bit code
arm - bit 0 = thumb, bit 1 = reverse endian
ppc - nonzero means little endian
other targets - unused
*/
void target_disas(FILE *out, target_ulong code, target_ulong size, int flags)
{
target_ulong pc;
int count;
struct disassemble_info disasm_info;
int (*print_insn)(bfd_vma pc, disassemble_info *info);
INIT_DISASSEMBLE_INFO(disasm_info, out, fprintf);
disasm_info.read_memory_func = target_read_memory;
disasm_info.buffer_vma = code;
disasm_info.buffer_length = size;
disasm_info.print_address_func = generic_print_target_address;
#ifdef TARGET_WORDS_BIGENDIAN
disasm_info.endian = BFD_ENDIAN_BIG;
#else
disasm_info.endian = BFD_ENDIAN_LITTLE;
#endif
#if defined(TARGET_I386)
if (flags == 2)
disasm_info.mach = bfd_mach_x86_64;
else if (flags == 1)
disasm_info.mach = bfd_mach_i386_i8086;
else
disasm_info.mach = bfd_mach_i386_i386;
print_insn = print_insn_i386;
#elif defined(TARGET_ARM)
if (flags & 1) {
print_insn = print_insn_thumb1;
} else {
print_insn = print_insn_arm;
}
if (flags & 2) {
#ifdef TARGET_WORDS_BIGENDIAN
disasm_info.endian = BFD_ENDIAN_LITTLE;
#else
disasm_info.endian = BFD_ENDIAN_BIG;
#endif
}
#elif defined(TARGET_SPARC)
print_insn = print_insn_sparc;
#ifdef TARGET_SPARC64
disasm_info.mach = bfd_mach_sparc_v9b;
#endif
#elif defined(TARGET_PPC)
if (flags >> 16)
disasm_info.endian = BFD_ENDIAN_LITTLE;
if (flags & 0xFFFF) {
/* If we have a precise definitions of the instructions set, use it */
disasm_info.mach = flags & 0xFFFF;
} else {
#ifdef TARGET_PPC64
disasm_info.mach = bfd_mach_ppc64;
#else
disasm_info.mach = bfd_mach_ppc;
#endif
}
print_insn = print_insn_ppc;
#elif defined(TARGET_M68K)
print_insn = print_insn_m68k;
#elif defined(TARGET_MIPS)
#ifdef TARGET_WORDS_BIGENDIAN
print_insn = print_insn_big_mips;
#else
print_insn = print_insn_little_mips;
#endif
#elif defined(TARGET_SH4)
disasm_info.mach = bfd_mach_sh4;
print_insn = print_insn_sh;
#elif defined(TARGET_ALPHA)
disasm_info.mach = bfd_mach_alpha_ev6;
print_insn = print_insn_alpha;
#elif defined(TARGET_CRIS)
if (flags != 32) {
disasm_info.mach = bfd_mach_cris_v0_v10;
print_insn = print_insn_crisv10;
} else {
disasm_info.mach = bfd_mach_cris_v32;
print_insn = print_insn_crisv32;
}
#elif defined(TARGET_S390X)
disasm_info.mach = bfd_mach_s390_64;
print_insn = print_insn_s390;
#elif defined(TARGET_MICROBLAZE)
disasm_info.mach = bfd_arch_microblaze;
print_insn = print_insn_microblaze;
#elif defined(TARGET_LM32)
disasm_info.mach = bfd_mach_lm32;
print_insn = print_insn_lm32;
#else
fprintf(out, "0x" TARGET_FMT_lx
": Asm output not supported on this arch\n", code);
return;
#endif
for (pc = code; size > 0; pc += count, size -= count) {
fprintf(out, "0x" TARGET_FMT_lx ": ", pc);
count = print_insn(pc, &disasm_info);
#if 0
{
int i;
uint8_t b;
fprintf(out, " {");
for(i = 0; i < count; i++) {
target_read_memory(pc + i, &b, 1, &disasm_info);
fprintf(out, " %02x", b);
}
fprintf(out, " }");
}
#endif
fprintf(out, "\n");
if (count < 0)
break;
if (size < count) {
fprintf(out,
"Disassembler disagrees with translator over instruction "
"decoding\n"
"Please report this to qemu-devel@nongnu.org\n");
break;
}
}
}
/* Disassemble this for me please... (debugging). */
void disas(FILE *out, void *code, unsigned long size)
{
uintptr_t pc;
int count;
struct disassemble_info disasm_info;
int (*print_insn)(bfd_vma pc, disassemble_info *info);
INIT_DISASSEMBLE_INFO(disasm_info, out, fprintf);
disasm_info.print_address_func = generic_print_host_address;
disasm_info.buffer = code;
disasm_info.buffer_vma = (uintptr_t)code;
disasm_info.buffer_length = size;
#ifdef HOST_WORDS_BIGENDIAN
disasm_info.endian = BFD_ENDIAN_BIG;
#else
disasm_info.endian = BFD_ENDIAN_LITTLE;
#endif
#if defined(CONFIG_TCG_INTERPRETER)
print_insn = print_insn_tci;
#elif defined(__i386__)
disasm_info.mach = bfd_mach_i386_i386;
print_insn = print_insn_i386;
#elif defined(__x86_64__)
disasm_info.mach = bfd_mach_x86_64;
print_insn = print_insn_i386;
#elif defined(_ARCH_PPC)
print_insn = print_insn_ppc;
#elif defined(__alpha__)
print_insn = print_insn_alpha;
#elif defined(__sparc__)
print_insn = print_insn_sparc;
#if defined(__sparc_v8plus__) || defined(__sparc_v8plusa__) || defined(__sparc_v9__)
disasm_info.mach = bfd_mach_sparc_v9b;
#endif
#elif defined(__arm__)
print_insn = print_insn_arm;
#elif defined(__MIPSEB__)
print_insn = print_insn_big_mips;
#elif defined(__MIPSEL__)
print_insn = print_insn_little_mips;
#elif defined(__m68k__)
print_insn = print_insn_m68k;
#elif defined(__s390__)
print_insn = print_insn_s390;
#elif defined(__hppa__)
print_insn = print_insn_hppa;
#elif defined(__ia64__)
print_insn = print_insn_ia64;
#else
fprintf(out, "0x%lx: Asm output not supported on this arch\n",
(long) code);
return;
#endif
for (pc = (uintptr_t)code; size > 0; pc += count, size -= count) {
fprintf(out, "0x%08" PRIxPTR ": ", pc);
count = print_insn(pc, &disasm_info);
fprintf(out, "\n");
if (count < 0)
break;
}
}
/* Look up symbol for debugging purpose. Returns "" if unknown. */
const char *lookup_symbol(target_ulong orig_addr)
{
const char *symbol = "";
struct syminfo *s;
for (s = syminfos; s; s = s->next) {
symbol = s->lookup_symbol(s, orig_addr);
if (symbol[0] != '\0') {
break;
}
}
return symbol;
}
#if !defined(CONFIG_USER_ONLY)
#include "monitor.h"
static int monitor_disas_is_physical;
static CPUArchState *monitor_disas_env;
static int
monitor_read_memory (bfd_vma memaddr, bfd_byte *myaddr, int length,
struct disassemble_info *info)
{
if (monitor_disas_is_physical) {
cpu_physical_memory_read(memaddr, myaddr, length);
} else {
cpu_memory_rw_debug(monitor_disas_env, memaddr,myaddr, length, 0);
}
return 0;
}
static int GCC_FMT_ATTR(2, 3)
monitor_fprintf(FILE *stream, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
monitor_vprintf((Monitor *)stream, fmt, ap);
va_end(ap);
return 0;
}
void monitor_disas(Monitor *mon, CPUArchState *env,
target_ulong pc, int nb_insn, int is_physical, int flags)
{
int count, i;
struct disassemble_info disasm_info;
int (*print_insn)(bfd_vma pc, disassemble_info *info);
INIT_DISASSEMBLE_INFO(disasm_info, (FILE *)mon, monitor_fprintf);
monitor_disas_env = env;
monitor_disas_is_physical = is_physical;
disasm_info.read_memory_func = monitor_read_memory;
disasm_info.print_address_func = generic_print_target_address;
disasm_info.buffer_vma = pc;
#ifdef TARGET_WORDS_BIGENDIAN
disasm_info.endian = BFD_ENDIAN_BIG;
#else
disasm_info.endian = BFD_ENDIAN_LITTLE;
#endif
#if defined(TARGET_I386)
if (flags == 2)
disasm_info.mach = bfd_mach_x86_64;
else if (flags == 1)
disasm_info.mach = bfd_mach_i386_i8086;
else
disasm_info.mach = bfd_mach_i386_i386;
print_insn = print_insn_i386;
#elif defined(TARGET_ARM)
print_insn = print_insn_arm;
#elif defined(TARGET_ALPHA)
print_insn = print_insn_alpha;
#elif defined(TARGET_SPARC)
print_insn = print_insn_sparc;
#ifdef TARGET_SPARC64
disasm_info.mach = bfd_mach_sparc_v9b;
#endif
#elif defined(TARGET_PPC)
#ifdef TARGET_PPC64
disasm_info.mach = bfd_mach_ppc64;
#else
disasm_info.mach = bfd_mach_ppc;
#endif
print_insn = print_insn_ppc;
#elif defined(TARGET_M68K)
print_insn = print_insn_m68k;
#elif defined(TARGET_MIPS)
#ifdef TARGET_WORDS_BIGENDIAN
print_insn = print_insn_big_mips;
#else
print_insn = print_insn_little_mips;
#endif
#elif defined(TARGET_SH4)
disasm_info.mach = bfd_mach_sh4;
print_insn = print_insn_sh;
#elif defined(TARGET_S390X)
disasm_info.mach = bfd_mach_s390_64;
print_insn = print_insn_s390;
#elif defined(TARGET_LM32)
disasm_info.mach = bfd_mach_lm32;
print_insn = print_insn_lm32;
#else
monitor_printf(mon, "0x" TARGET_FMT_lx
": Asm output not supported on this arch\n", pc);
return;
#endif
for(i = 0; i < nb_insn; i++) {
monitor_printf(mon, "0x" TARGET_FMT_lx ": ", pc);
count = print_insn(pc, &disasm_info);
monitor_printf(mon, "\n");
if (count < 0)
break;
pc += count;
}
}
#endif