diff options
Diffstat (limited to 'gdb')
| -rw-r--r-- | gdb/windows-nat.c | 44 |
1 files changed, 31 insertions, 13 deletions
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c index 28f142c..6fdd1f3 100644 --- a/gdb/windows-nat.c +++ b/gdb/windows-nat.c @@ -662,23 +662,19 @@ windows_fetch_one_register (struct regcache *regcache, gdb_assert (gdbarch_pc_regnum (gdbarch) >= 0); gdb_assert (!gdbarch_write_pc_p (gdbarch)); - if (r == I387_FISEG_REGNUM (tdep)) + /* GDB treats some registers as 32-bit, where they are in fact only + 16 bits long. These cases must be handled specially to avoid + reading extraneous bits from the context. */ + if (r == I387_FISEG_REGNUM (tdep) || windows_process.segment_register_p (r)) { - long l = *((long *) context_offset) & 0xffff; - regcache->raw_supply (r, (char *) &l); + gdb_byte bytes[4] = {}; + memcpy (bytes, context_offset, 2); + regcache->raw_supply (r, bytes); } else if (r == I387_FOP_REGNUM (tdep)) { long l = (*((long *) context_offset) >> 16) & ((1 << 11) - 1); - regcache->raw_supply (r, (char *) &l); - } - else if (windows_process.segment_register_p (r)) - { - /* GDB treats segment registers as 32bit registers, but they are - in fact only 16 bits long. Make sure we do not read extra - bits from our source buffer. */ - long l = *((long *) context_offset) & 0xffff; - regcache->raw_supply (r, (char *) &l); + regcache->raw_supply (r, &l); } else { @@ -799,7 +795,29 @@ windows_store_one_register (const struct regcache *regcache, context_ptr = (char *) &th->wow64_context; #endif - regcache->raw_collect (r, context_ptr + windows_process.mappings[r]); + struct gdbarch *gdbarch = regcache->arch (); + i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (gdbarch); + + /* GDB treats some registers as 32-bit, where they are in fact only + 16 bits long. These cases must be handled specially to avoid + overwriting other registers in the context. */ + if (r == I387_FISEG_REGNUM (tdep) || windows_process.segment_register_p (r)) + { + gdb_byte bytes[4]; + regcache->raw_collect (r, bytes); + memcpy (context_ptr + windows_process.mappings[r], bytes, 2); + } + else if (r == I387_FOP_REGNUM (tdep)) + { + gdb_byte bytes[4]; + regcache->raw_collect (r, bytes); + /* The value of FOP occupies the top two bytes in the context, + so write the two low-order bytes from the cache into the + appropriate spot. */ + memcpy (context_ptr + windows_process.mappings[r] + 2, bytes, 2); + } + else + regcache->raw_collect (r, context_ptr + windows_process.mappings[r]); } /* Store a new register value into the context of the thread tied to |