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x86emu: Fix more mis-decoding of the data prefix 

cc2c73ddcb4370a7c3ad439cda4da825156c26c9'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

Imported from:
http://cgit.freedesktop.org/xorg/xserver/commit/hw/xfree86/x86emu?id=bb18f277156c08be028a6e12d8987fb1593e9168

Signed-off-by: Stefan Reinauer <reinauer@google.com>

Change-Id: I83e6245d9748ee86722cfb7d8ac65258c35c013c
Reviewed-by: Julien Cristau <jcristau@debian.org>
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-on: http://review.coreboot.org/1366
Tested-by: build bot (Jenkins)
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
This commit is contained in:
Stefan Reinauer 2012-07-26 16:25:53 -07:00 committed by Patrick Georgi
parent b25374cec5
commit 3b69578cd2
1 changed files with 47 additions and 20 deletions
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67
src/devices/oprom/x86emu/ops.c
View File

@ -2294,15 +2294,20 @@ 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");
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_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 ");
/* XXX
*
@ -2313,8 +2318,12 @@ 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();
}
@ -4258,17 +4267,30 @@ Handles opcode 0xe8
****************************************************************************/
static void x86emuOp_call_near_IMM(u8 X86EMU_UNUSED(op1))
{
s16 ip;
s16 ip16 = 0; /* Initialize to keep GCC silent */
s32 ip32 = 0;
START_OF_INSTR();
DECODE_PRINTF("CALL\t");
ip = (s16) fetch_word_imm();
ip += (s16) M.x86.R_IP; /* CHECK SIGN */
DECODE_PRINTF2("%04x\n", 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", 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();
}
@ -4299,17 +4321,22 @@ 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);
JMP_TRACE(M.x86.saved_cs, M.x86.saved_ip, cs, ip, " FAR ");
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();