|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH 1/6] x86emul: extend / amend supported FPU opcodes
First of all there are a number of secondary encodings both Intel and
AMD support, but which aren't formally documented.
Next there are a few more no-ops - instructions which served a purpose
only on 8087 or 287.
Further switch from fail_if() to raising of #UD in a couple of places
(as the decoding of FPU opcodes should now be complete except where
explictly marked as todo).
Also adjust a few comments.
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -3672,18 +3672,18 @@ x86_emulate(
host_and_vcpu_must_have(fpu);
switch ( modrm )
{
- case 0xc0 ... 0xc7: /* fadd %stN,%stN */
- case 0xc8 ... 0xcf: /* fmul %stN,%stN */
- case 0xd0 ... 0xd7: /* fcom %stN,%stN */
- case 0xd8 ... 0xdf: /* fcomp %stN,%stN */
- case 0xe0 ... 0xe7: /* fsub %stN,%stN */
- case 0xe8 ... 0xef: /* fsubr %stN,%stN */
- case 0xf0 ... 0xf7: /* fdiv %stN,%stN */
- case 0xf8 ... 0xff: /* fdivr %stN,%stN */
+ case 0xc0 ... 0xc7: /* fadd %stN,%st */
+ case 0xc8 ... 0xcf: /* fmul %stN,%st */
+ case 0xd0 ... 0xd7: /* fcom %stN,%st */
+ case 0xd8 ... 0xdf: /* fcomp %stN,%st */
+ case 0xe0 ... 0xe7: /* fsub %stN,%st */
+ case 0xe8 ... 0xef: /* fsubr %stN,%st */
+ case 0xf0 ... 0xf7: /* fdiv %stN,%st */
+ case 0xf8 ... 0xff: /* fdivr %stN,%st */
emulate_fpu_insn_stub(0xd8, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ ASSERT(ea.type == OP_MEM);
ea.bytes = 4;
src = ea;
if ( (rc = ops->read(src.mem.seg, src.mem.off, &src.val,
@@ -3729,6 +3729,7 @@ x86_emulate(
case 0xc0 ... 0xc7: /* fld %stN */
case 0xc8 ... 0xcf: /* fxch %stN */
case 0xd0: /* fnop */
+ case 0xd8 ... 0xdf: /* fstp %stN (alternative encoding) */
case 0xe0: /* fchs */
case 0xe1: /* fabs */
case 0xe4: /* ftst */
@@ -3758,7 +3759,7 @@ x86_emulate(
emulate_fpu_insn_stub(0xd9, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ generate_exception_if(ea.type != OP_MEM, EXC_UD);
switch ( modrm_reg & 7 )
{
case 0: /* fld m32fp */
@@ -3781,7 +3782,8 @@ x86_emulate(
dst.type = OP_MEM;
emulate_fpu_insn_memdst("fstps", dst.val);
break;
- /* case 4: fldenv - TODO */
+ case 4: /* fldenv - TODO */
+ goto cannot_emulate;
case 5: /* fldcw m2byte */
ea.bytes = 2;
src = ea;
@@ -3790,7 +3792,8 @@ x86_emulate(
goto done;
emulate_fpu_insn_memsrc("fldcw", src.val);
break;
- /* case 6: fstenv - TODO */
+ case 6: /* fnstenv - TODO */
+ goto cannot_emulate;
case 7: /* fnstcw m2byte */
ea.bytes = 2;
dst = ea;
@@ -3798,7 +3801,7 @@ x86_emulate(
emulate_fpu_insn_memdst("fnstcw", dst.val);
break;
default:
- goto cannot_emulate;
+ generate_exception_if(true, EXC_UD);
}
}
break;
@@ -3818,7 +3821,7 @@ x86_emulate(
emulate_fpu_insn_stub(0xda, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ generate_exception_if(ea.type != OP_MEM, EXC_UD);
ea.bytes = 4;
src = ea;
if ( (rc = ops->read(src.mem.seg, src.mem.off, &src.val,
@@ -3867,16 +3870,16 @@ x86_emulate(
vcpu_must_have_cmov();
emulate_fpu_insn_stub_eflags(0xdb, modrm);
break;
+ case 0xe0: /* fneni - 8087 only, ignored by 287 */
+ case 0xe1: /* fndisi - 8087 only, ignored by 287 */
case 0xe2: /* fnclex */
- emulate_fpu_insn("fnclex");
- break;
case 0xe3: /* fninit */
- emulate_fpu_insn("fninit");
- break;
- case 0xe4: /* fsetpm - 287 only, ignored by 387 */
+ case 0xe4: /* fnsetpm - 287 only, ignored by 387 */
+ /* case 0xe5: frstpm - 287 only, #UD on 387 */
+ emulate_fpu_insn_stub(0xdb, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ generate_exception_if(ea.type != OP_MEM, EXC_UD);
switch ( modrm_reg & 7 )
{
case 0: /* fild m32i */
@@ -3921,7 +3924,7 @@ x86_emulate(
emulate_fpu_insn_memdst("fstpt", dst.val);
break;
default:
- goto cannot_emulate;
+ generate_exception_if(true, EXC_UD);
}
}
break;
@@ -3930,16 +3933,18 @@ x86_emulate(
host_and_vcpu_must_have(fpu);
switch ( modrm )
{
- case 0xc0 ... 0xc7: /* fadd %stN */
- case 0xc8 ... 0xcf: /* fmul %stN */
- case 0xe0 ... 0xe7: /* fsubr %stN */
- case 0xe8 ... 0xef: /* fsub %stN */
- case 0xf0 ... 0xf7: /* fdivr %stN */
- case 0xf8 ... 0xff: /* fdiv %stN */
+ case 0xc0 ... 0xc7: /* fadd %st,%stN */
+ case 0xc8 ... 0xcf: /* fmul %st,%stN */
+ case 0xd0 ... 0xd7: /* fcom %stN,%st (alternative encoding) */
+ case 0xd8 ... 0xdf: /* fcomp %stN,%st (alternative encoding) */
+ case 0xe0 ... 0xe7: /* fsubr %st,%stN */
+ case 0xe8 ... 0xef: /* fsub %st,%stN */
+ case 0xf0 ... 0xf7: /* fdivr %st,%stN */
+ case 0xf8 ... 0xff: /* fdiv %st,%stN */
emulate_fpu_insn_stub(0xdc, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ ASSERT(ea.type == OP_MEM);
ea.bytes = 8;
src = ea;
if ( (rc = ops->read(src.mem.seg, src.mem.off, &src.val,
@@ -3980,6 +3985,7 @@ x86_emulate(
switch ( modrm )
{
case 0xc0 ... 0xc7: /* ffree %stN */
+ case 0xc8 ... 0xcf: /* fxch %stN (alternative encoding) */
case 0xd0 ... 0xd7: /* fst %stN */
case 0xd8 ... 0xdf: /* fstp %stN */
case 0xe0 ... 0xe7: /* fucom %stN */
@@ -3987,7 +3993,7 @@ x86_emulate(
emulate_fpu_insn_stub(0xdd, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ generate_exception_if(ea.type != OP_MEM, EXC_UD);
switch ( modrm_reg & 7 )
{
case 0: /* fld m64fp */;
@@ -4017,6 +4023,9 @@ x86_emulate(
dst.type = OP_MEM;
emulate_fpu_insn_memdst("fstpl", dst.val);
break;
+ case 4: /* frstor - TODO */
+ case 6: /* fnsave - TODO */
+ goto cannot_emulate;
case 7: /* fnstsw m2byte */
ea.bytes = 2;
dst = ea;
@@ -4024,7 +4033,7 @@ x86_emulate(
emulate_fpu_insn_memdst("fnstsw", dst.val);
break;
default:
- goto cannot_emulate;
+ generate_exception_if(true, EXC_UD);
}
}
break;
@@ -4035,6 +4044,7 @@ x86_emulate(
{
case 0xc0 ... 0xc7: /* faddp %stN */
case 0xc8 ... 0xcf: /* fmulp %stN */
+ case 0xd0 ... 0xd7: /* fcomp %stN (alternative encoding) */
case 0xd9: /* fcompp */
case 0xe0 ... 0xe7: /* fsubrp %stN */
case 0xe8 ... 0xef: /* fsubp %stN */
@@ -4043,7 +4053,7 @@ x86_emulate(
emulate_fpu_insn_stub(0xde, modrm);
break;
default:
- fail_if(modrm >= 0xc0);
+ generate_exception_if(ea.type != OP_MEM, EXC_UD);
ea.bytes = 2;
src = ea;
if ( (rc = ops->read(src.mem.seg, src.mem.off, &src.val,
@@ -4090,13 +4100,19 @@ x86_emulate(
dst.reg = (unsigned long *)&_regs.eax;
emulate_fpu_insn_memdst("fnstsw", dst.val);
break;
+ case 0xc0 ... 0xc7: /* ffreep %stN */
case 0xe8 ... 0xef: /* fucomip %stN */
case 0xf0 ... 0xf7: /* fcomip %stN */
vcpu_must_have_cmov();
emulate_fpu_insn_stub_eflags(0xdf, modrm);
break;
+ case 0xc8 ... 0xcf: /* fxch %stN (alternative encoding) */
+ case 0xd0 ... 0xd7: /* fstp %stN (alternative encoding) */
+ case 0xd8 ... 0xdf: /* fstp %stN (alternative encoding) */
+ emulate_fpu_insn_stub(0xdf, modrm);
+ break;
default:
- fail_if(modrm >= 0xc0);
+ generate_exception_if(ea.type != OP_MEM, EXC_UD);
switch ( modrm_reg & 7 )
{
case 0: /* fild m16i */
Attachment:
x86emul-FPU-opcodes.patch _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx https://lists.xen.org/xen-devel
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |