Commit bb18f277 authored by Adam Jackson's avatar Adam Jackson 🎧
Browse files

x86emu: Fix more mis-decoding of the data prefix

cc2c73dd's three-cent titanium tax
doesn't go too far enough.  Fix the rest of the call and jmp
instructions to handle the data prefix correctly.

Reference: Intel 64 and IA-32 Architectures Software Developer's Manual
Volume 2A: Instruction Set Reference, A-M

http://www.intel.com/Assets/PDF/manual/253666.pdf

Reviewed-by: Julien Cristau's avatarJulien Cristau <jcristau@debian.org>
Signed-off-by: Adam Jackson's avatarAdam Jackson <ajax@redhat.com>
parent 261d0d16
......@@ -7065,15 +7065,20 @@ Handles opcode 0x9a
****************************************************************************/
static void x86emuOp_call_far_IMM(u8 X86EMU_UNUSED(op1))
{
u16 farseg, faroff;
u32 farseg, faroff;
START_OF_INSTR();
DECODE_PRINTF("CALL\t");
DECODE_PRINTF("CALL\t");
if (M.x86.mode & SYSMODE_PREFIX_DATA) {
faroff = fetch_long_imm();
farseg = fetch_word_imm();
} else {
faroff = fetch_word_imm();
farseg = fetch_word_imm();
DECODE_PRINTF2("%04x:", farseg);
DECODE_PRINTF2("%04x\n", faroff);
CALL_TRACE(M.x86.saved_cs, M.x86.saved_ip, farseg, faroff, "FAR ");
}
DECODE_PRINTF2("%04x:", farseg);
DECODE_PRINTF2("%04x\n", faroff);
CALL_TRACE(M.x86.saved_cs, M.x86.saved_ip, farseg, faroff, "FAR ");
/* XXX
*
......@@ -7084,8 +7089,12 @@ static void x86emuOp_call_far_IMM(u8 X86EMU_UNUSED(op1))
TRACE_AND_STEP();
push_word(M.x86.R_CS);
M.x86.R_CS = farseg;
push_word(M.x86.R_IP);
M.x86.R_IP = faroff;
if (M.x86.mode & SYSMODE_PREFIX_DATA) {
push_long(M.x86.R_EIP);
} else {
push_word(M.x86.R_IP);
}
M.x86.R_EIP = faroff & 0xffff;
DECODE_CLEAR_SEGOVR();
END_OF_INSTR();
}
......@@ -9670,17 +9679,30 @@ Handles opcode 0xe8
****************************************************************************/
static void x86emuOp_call_near_IMM(u8 X86EMU_UNUSED(op1))
{
s16 ip;
s16 ip16;
s32 ip32;
START_OF_INSTR();
DECODE_PRINTF("CALL\t");
ip = (s16) fetch_word_imm();
ip += (s16) M.x86.R_IP; /* CHECK SIGN */
DECODE_PRINTF2("%04x\n", (u16)ip);
CALL_TRACE(M.x86.saved_cs, M.x86.saved_ip, M.x86.R_CS, ip, "");
DECODE_PRINTF("CALL\t");
if (M.x86.mode & SYSMODE_PREFIX_DATA) {
ip32 = (s32) fetch_long_imm();
ip32 += (s16) M.x86.R_IP; /* CHECK SIGN */
DECODE_PRINTF2("%04x\n", (u16)ip32);
CALL_TRACE(M.x86.saved_cs, M.x86.saved_ip, M.x86.R_CS, ip32, "");
} else {
ip16 = (s16) fetch_word_imm();
ip16 += (s16) M.x86.R_IP; /* CHECK SIGN */
DECODE_PRINTF2("%04x\n", (u16)ip16);
CALL_TRACE(M.x86.saved_cs, M.x86.saved_ip, M.x86.R_CS, ip16, "");
}
TRACE_AND_STEP();
push_word(M.x86.R_IP);
M.x86.R_IP = ip;
if (M.x86.mode & SYSMODE_PREFIX_DATA) {
push_long(M.x86.R_EIP);
M.x86.R_EIP = ip32 & 0xffff;
} else {
push_word(M.x86.R_IP);
M.x86.R_EIP = ip16;
}
DECODE_CLEAR_SEGOVR();
END_OF_INSTR();
}
......@@ -9718,16 +9740,21 @@ Handles opcode 0xea
****************************************************************************/
static void x86emuOp_jump_far_IMM(u8 X86EMU_UNUSED(op1))
{
u16 cs, ip;
u16 cs;
u32 ip;
START_OF_INSTR();
DECODE_PRINTF("JMP\tFAR ");
ip = fetch_word_imm();
if (M.x86.mode & SYSMODE_PREFIX_DATA) {
ip = fetch_long_imm();
} else {
ip = fetch_word_imm();
}
cs = fetch_word_imm();
DECODE_PRINTF2("%04x:", cs);
DECODE_PRINTF2("%04x\n", ip);
TRACE_AND_STEP();
M.x86.R_IP = ip;
M.x86.R_EIP = ip & 0xffff;
M.x86.R_CS = cs;
DECODE_CLEAR_SEGOVR();
END_OF_INSTR();
......
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