#include "regcache.h"
#include "regset.h"
#include "symfile.h"
-
+#include "disasm.h"
#include "gdb_assert.h"
#include "amd64-tdep.h"
return insn;
}
-/* fprintf-function for amd64_insn_length.
- This function is a nop, we don't want to print anything, we just want to
- compute the length of the insn. */
-
-static int ATTR_FORMAT (printf, 2, 3)
-amd64_insn_length_fprintf (void *stream, const char *format, ...)
-{
- return 0;
-}
-
-/* Initialize a struct disassemble_info for amd64_insn_length. */
-
-static void
-amd64_insn_length_init_dis (struct gdbarch *gdbarch,
- struct disassemble_info *di,
- const gdb_byte *insn, int max_len,
- CORE_ADDR addr)
-{
- init_disassemble_info (di, NULL, amd64_insn_length_fprintf);
-
- /* init_disassemble_info installs buffer_read_memory, etc.
- so we don't need to do that here.
- The cast is necessary until disassemble_info is const-ified. */
- di->buffer = (gdb_byte *) insn;
- di->buffer_length = max_len;
- di->buffer_vma = addr;
-
- di->arch = gdbarch_bfd_arch_info (gdbarch)->arch;
- di->mach = gdbarch_bfd_arch_info (gdbarch)->mach;
- di->endian = gdbarch_byte_order (gdbarch);
- di->endian_code = gdbarch_byte_order_for_code (gdbarch);
-
- disassemble_init_for_target (di);
-}
-
-/* Return the length in bytes of INSN.
- MAX_LEN is the size of the buffer containing INSN.
- libopcodes currently doesn't export a utility to compute the
- instruction length, so use the disassembler until then. */
-
-static int
-amd64_insn_length (struct gdbarch *gdbarch,
- const gdb_byte *insn, int max_len, CORE_ADDR addr)
-{
- struct disassemble_info di;
-
- amd64_insn_length_init_dis (gdbarch, &di, insn, max_len, addr);
-
- return gdbarch_print_insn (gdbarch, addr, &di);
-}
-
/* Return an integer register (other than RSP) that is unused as an input
operand in INSN.
In order to not require adding a rex prefix if the insn doesn't already
/* Compute the rip-relative address. */
disp = extract_signed_integer (insn, sizeof (int32_t), byte_order);
- insn_length = amd64_insn_length (gdbarch, dsc->insn_buf, dsc->max_len, from);
+ insn_length = gdb_buffered_insn_length (gdbarch, dsc->insn_buf,
+ dsc->max_len, from);
rip_base = from + insn_length;
/* We need a register to hold the address.
paddress (gdbarch, retaddr));
}
}
+
+/* If the instruction INSN uses RIP-relative addressing, return the
+ offset into the raw INSN where the displacement to be adjusted is
+ found. Returns 0 if the instruction doesn't use RIP-relative
+ addressing. */
+
+static int
+rip_relative_offset (struct amd64_insn *insn)
+{
+ if (insn->modrm_offset != -1)
+ {
+ gdb_byte modrm = insn->raw_insn[insn->modrm_offset];
+
+ if ((modrm & 0xc7) == 0x05)
+ {
+ /* The displacement is found right after the ModRM byte. */
+ return insn->modrm_offset + 1;
+ }
+ }
+
+ return 0;
+}
+
+static void
+append_insns (CORE_ADDR *to, ULONGEST len, const gdb_byte *buf)
+{
+ target_write_memory (*to, buf, len);
+ *to += len;
+}
+
+void
+amd64_relocate_instruction (struct gdbarch *gdbarch,
+ CORE_ADDR *to, CORE_ADDR oldloc)
+{
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ int len = gdbarch_max_insn_length (gdbarch);
+ /* Extra space for sentinels. */
+ int fixup_sentinel_space = len;
+ gdb_byte *buf = xmalloc (len + fixup_sentinel_space);
+ struct amd64_insn insn_details;
+ int offset = 0;
+ LONGEST rel32, newrel;
+ gdb_byte *insn;
+ int insn_length;
+
+ read_memory (oldloc, buf, len);
+
+ /* Set up the sentinel space so we don't have to worry about running
+ off the end of the buffer. An excessive number of leading prefixes
+ could otherwise cause this. */
+ memset (buf + len, 0, fixup_sentinel_space);
+
+ insn = buf;
+ amd64_get_insn_details (insn, &insn_details);
+
+ insn_length = gdb_buffered_insn_length (gdbarch, insn, len, oldloc);
+
+ /* Skip legacy instruction prefixes. */
+ insn = amd64_skip_prefixes (insn);
+
+ /* Adjust calls with 32-bit relative addresses as push/jump, with
+ the address pushed being the location where the original call in
+ the user program would return to. */
+ if (insn[0] == 0xe8)
+ {
+ gdb_byte push_buf[16];
+ unsigned int ret_addr;
+
+ /* Where "ret" in the original code will return to. */
+ ret_addr = oldloc + insn_length;
+ push_buf[0] = 0x68; /* pushq $... */
+ memcpy (&push_buf[1], &ret_addr, 4);
+ /* Push the push. */
+ append_insns (to, 5, push_buf);
+
+ /* Convert the relative call to a relative jump. */
+ insn[0] = 0xe9;
+
+ /* Adjust the destination offset. */
+ rel32 = extract_signed_integer (insn + 1, 4, byte_order);
+ newrel = (oldloc - *to) + rel32;
+ store_signed_integer (insn + 1, 4, newrel, byte_order);
+
+ /* Write the adjusted jump into its displaced location. */
+ append_insns (to, 5, insn);
+ return;
+ }
+
+ offset = rip_relative_offset (&insn_details);
+ if (!offset)
+ {
+ /* Adjust jumps with 32-bit relative addresses. Calls are
+ already handled above. */
+ if (insn[0] == 0xe9)
+ offset = 1;
+ /* Adjust conditional jumps. */
+ else if (insn[0] == 0x0f && (insn[1] & 0xf0) == 0x80)
+ offset = 2;
+ }
+
+ if (offset)
+ {
+ rel32 = extract_signed_integer (insn + offset, 4, byte_order);
+ newrel = (oldloc - *to) + rel32;
+ store_signed_integer (insn + offset, 4, newrel, byte_order);
+ if (debug_displaced)
+ fprintf_unfiltered (gdb_stdlog,
+ "Adjusted insn rel32=0x%s at 0x%s to"
+ " rel32=0x%s at 0x%s\n",
+ hex_string (rel32), paddress (gdbarch, oldloc),
+ hex_string (newrel), paddress (gdbarch, *to));
+ }
+
+ /* Write the adjusted instruction into its displaced location. */
+ append_insns (to, insn_length, buf);
+}
+
\f
/* The maximum number of saved registers. This should include %rip. */
#define AMD64_NUM_SAVED_REGS AMD64_NUM_GREGS
struct regcache *regcache, int regnum,
const void *xstateregs, size_t len)
{
- const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch);
amd64_supply_xsave (regcache, regnum, xstateregs);
}
const struct regcache *regcache,
int regnum, void *xstateregs, size_t len)
{
- const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch);
amd64_collect_xsave (regcache, regnum, xstateregs, 1);
}
amd64_regset_from_core_section);
set_gdbarch_get_longjmp_target (gdbarch, amd64_get_longjmp_target);
+
+ set_gdbarch_relocate_instruction (gdbarch, amd64_relocate_instruction);
}
/* Provide a prototype to silence -Wmissing-prototypes. */
projects / deliverable / binutils-gdb.git / blobdiff