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Changes for new flags.

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Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@918
This commit is contained in:
Sjoerd van der Berg 2003-04-13 18:34:43 +00:00
parent 5375838637
commit b77dea601e
1 changed files with 246 additions and 12 deletions
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258
src/cpu/flags.cpp
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@ -29,7 +29,7 @@
/* CF Carry Flag -- Set on high-order bit carry or borrow; cleared
otherwise.
*/
bool get_CF(void) {
Bitu get_CF(void) {
switch (flags.type) {
case t_UNKNOWN:
@ -44,7 +44,7 @@ bool get_CF(void) {
case t_RCLb:
case t_RCLw:
case t_RCLd:
return flags.cf;
return GETFLAG(CF);
break;
case t_ADDb:
return (flags.result.b<flags.var1.b);
@ -143,7 +143,7 @@ bool get_CF(void) {
four bits of AL; cleared otherwise. Used for decimal
arithmetic.
*/
bool get_AF(void) {
Bitu get_AF(void) {
Bitu type=flags.type;
again:
switch (type) {
@ -160,7 +160,7 @@ again:
case t_RORd:
case t_RCLd:
case t_RCRd:
return flags.af;
return GETFLAG(AF);
case t_CF:
type=flags.prev_type;
goto again;
@ -237,7 +237,7 @@ again:
/* ZF Zero Flag -- Set if result is zero; cleared otherwise.
*/
bool get_ZF(void) {
Bitu get_ZF(void) {
Bitu type=flags.type;
again:
switch (type) {
@ -254,7 +254,7 @@ again:
case t_RORd:
case t_RCLd:
case t_RCRd:
return flags.zf;
return GETFLAG(ZF);
case t_CF:
type=flags.prev_type;
goto again;
@ -321,7 +321,7 @@ again:
/* SF Sign Flag -- Set equal to high-order bit of result (0 is
positive, 1 if negative).
*/
bool get_SF(void) {
Bitu get_SF(void) {
Bitu type=flags.type;
again:
switch (type) {
@ -338,7 +338,7 @@ again:
case t_RORd:
case t_RCLd:
case t_RCRd:
return flags.sf;
return GETFLAG(SF);
case t_CF:
type=flags.prev_type;
goto again;
@ -403,7 +403,7 @@ again:
return false;
}
bool get_OF(void) {
Bitu get_OF(void) {
Bit8u var1b7, var2b7, resultb7;
Bit16u var1w15, var2w15, resultw15;
Bit32u var1d31, var2d31, resultd31;
@ -419,7 +419,7 @@ again:
case t_SARb:
case t_SARw:
case t_SARd:
return flags.of;
return GETFLAG(OF);
case t_CF:
type=flags.prev_type;
goto again;
@ -563,10 +563,10 @@ static bool parity_lookup[256] = {
1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
};
bool get_PF(void) {
Bitu get_PF(void) {
switch (flags.type) {
case t_UNKNOWN:
return flags.pf;
return GETFLAG(PF);
default:
return (parity_lookup[flags.result.b]);;
};
@ -574,3 +574,237 @@ bool get_PF(void) {
}
#define SET_FLAG(TYPE,TEST) if ( TEST ) new_flags|=TYPE
#if 0
#endif
Bitu get_Flags(void) {
Bitu new_flags=0;
switch (flags.type) {
case t_ADDb:
SET_FLAG(FLAG_CF,(flags.result.b<flags.var1.b));
SET_FLAG(FLAG_AF,(((flags.var1.b ^ flags.var2.b) ^ flags.result.b) & 0x10)>0);
break;
case t_ADDw:
SET_FLAG(FLAG_CF,(flags.result.w<flags.var1.w));
SET_FLAG(FLAG_AF,(((flags.var1.w ^ flags.var2.w) ^ flags.result.w) & 0x10)>0);
break;
case t_ADDd:
SET_FLAG(FLAG_CF,(flags.result.d<flags.var1.d));
SET_FLAG(FLAG_AF,(((flags.var1.d ^ flags.var2.d) ^ flags.result.d) & 0x10)>0);
break;
case t_ADCb:
SET_FLAG(FLAG_CF,(flags.result.b < flags.var1.b) || (flags.oldcf && (flags.result.b == flags.var1.b)));
SET_FLAG(FLAG_AF,(((flags.var1.b ^ flags.var2.b) ^ flags.result.b) & 0x10)>0);
break;
case t_ADCw:
SET_FLAG(FLAG_CF,(flags.result.w < flags.var1.w) || (flags.oldcf && (flags.result.w == flags.var1.w)));
SET_FLAG(FLAG_AF,(((flags.var1.w ^ flags.var2.w) ^ flags.result.w) & 0x10)>0);
break;
case t_ADCd:
SET_FLAG(FLAG_CF,(flags.result.d < flags.var1.d) || (flags.oldcf && (flags.result.d == flags.var1.d)));
SET_FLAG(FLAG_AF,(((flags.var1.d ^ flags.var2.d) ^ flags.result.d) & 0x10)>0);
break;
case t_SBBb:
SET_FLAG(FLAG_CF,(flags.var1.b < flags.result.b) || (flags.oldcf && (flags.var2.b==0xff)));
SET_FLAG(FLAG_AF,(((flags.var1.b ^ flags.var2.b) ^ flags.result.b) & 0x10)>0);
break;
case t_SBBw:
SET_FLAG(FLAG_CF,(flags.var1.w < flags.result.w) || (flags.oldcf && (flags.var2.w==0xffff)));
SET_FLAG(FLAG_AF,(((flags.var1.w ^ flags.var2.w) ^ flags.result.w) & 0x10)>0);
break;
case t_SBBd:
SET_FLAG(FLAG_CF,(flags.var1.d < flags.result.d) || (flags.oldcf && (flags.var2.d==0xffffffff)));
SET_FLAG(FLAG_AF,(((flags.var1.d ^ flags.var2.d) ^ flags.result.d) & 0x10)>0);
break;
case t_SUBb:
case t_CMPb:
SET_FLAG(FLAG_CF,(flags.var1.b<flags.var2.b));
SET_FLAG(FLAG_AF,(((flags.var1.b ^ flags.var2.b) ^ flags.result.b) & 0x10)>0);
break;
case t_SUBw:
case t_CMPw:
SET_FLAG(FLAG_CF,(flags.var1.w<flags.var2.w));
SET_FLAG(FLAG_AF,(((flags.var1.w ^ flags.var2.w) ^ flags.result.w) & 0x10)>0);
break;
case t_SUBd:
case t_CMPd:
SET_FLAG(FLAG_CF,(flags.var1.d<flags.var2.d));
SET_FLAG(FLAG_AF,(((flags.var1.d ^ flags.var2.d) ^ flags.result.d) & 0x10)>0);
break;
case t_ORb:
SET_FLAG(FLAG_CF,false);
break;
case t_ORw:
SET_FLAG(FLAG_CF,false);
break;
case t_ORd:
SET_FLAG(FLAG_CF,false);
break;
case t_TESTb:
case t_ANDb:
SET_FLAG(FLAG_CF,false);
break;
case t_TESTw:
case t_ANDw:
SET_FLAG(FLAG_CF,false);
break;
case t_TESTd:
case t_ANDd:
SET_FLAG(FLAG_CF,false);
break;
case t_XORb:
SET_FLAG(FLAG_CF,false);
break;
case t_XORw:
SET_FLAG(FLAG_CF,false);
break;
case t_XORd:
SET_FLAG(FLAG_CF,false);
break;
case t_SHLb:
if (flags.var2.b>8) SET_FLAG(FLAG_CF,false);
else SET_FLAG(FLAG_CF,(flags.var1.b >> (8-flags.var2.b)) & 1);
break;
case t_SHLw:
if (flags.var2.b>16) SET_FLAG(FLAG_CF,false);
else SET_FLAG(FLAG_CF,(flags.var1.w >> (16-flags.var2.b)) & 1);
break;
case t_SHLd:
SET_FLAG(FLAG_CF,(flags.var1.d >> (32 - flags.var2.b)) & 1);
break;
case t_DSHLw: /* Hmm this is not correct for shift higher than 16 */
SET_FLAG(FLAG_CF,(flags.var1.d >> (32 - flags.var2.b)) & 1);
break;
case t_DSHLd:
SET_FLAG(FLAG_CF,(flags.var1.d >> (32 - flags.var2.b)) & 1);
break;
case t_SHRb:
SET_FLAG(FLAG_CF,(flags.var1.b >> (flags.var2.b - 1)) & 1);
break;
case t_SHRw:
SET_FLAG(FLAG_CF,(flags.var1.w >> (flags.var2.b - 1)) & 1);
break;
case t_SHRd:
SET_FLAG(FLAG_CF,(flags.var1.d >> (flags.var2.b - 1)) & 1);
break;
case t_DSHRw: /* Hmm this is not correct for shift higher than 16 */
SET_FLAG(FLAG_CF,(flags.var1.d >> (flags.var2.b - 1)) & 1);
break;
case t_DSHRd:
SET_FLAG(FLAG_CF,(flags.var1.d >> (flags.var2.b - 1)) & 1);
break;
case t_SARb:
SET_FLAG(FLAG_CF,(((Bit8s) flags.var1.b) >> (flags.var2.b - 1)) & 1);
break;
case t_SARw:
SET_FLAG(FLAG_CF,(((Bit16s) flags.var1.w) >> (flags.var2.b - 1)) & 1);
break;
case t_SARd:
SET_FLAG(FLAG_CF,(((Bit32s) flags.var1.d) >> (flags.var2.b - 1)) & 1);
break;
case t_ROLb:
SET_FLAG(FLAG_CF,flags.result.b & 1);
break;
case t_ROLw:
SET_FLAG(FLAG_CF,flags.result.w & 1);
break;
case t_ROLd:
SET_FLAG(FLAG_CF,flags.result.d & 1);
break;
case t_RORb:
SET_FLAG(FLAG_CF,(flags.result.b & 0x80)>0);
break;
case t_RORw:
SET_FLAG(FLAG_CF,(flags.result.w & 0x8000)>0);
break;
case t_RORd:
SET_FLAG(FLAG_CF,(flags.result.d & 0x80000000)>0);
break;
case t_RCRb:
SET_FLAG(FLAG_CF,(flags.var1.b >> (flags.var2.b - 1)) & 1);
break;
case t_RCRw:
SET_FLAG(FLAG_CF,(flags.var1.w >> (flags.var2.b - 1)) & 1);
break;
case t_RCRd:
SET_FLAG(FLAG_CF,(flags.var1.d >> (flags.var2.b - 1)) & 1);
break;
case t_INCb:
SET_FLAG(FLAG_OF,(flags.result.b == 0x80));
SET_FLAG(FLAG_AF,((flags.result.b & 0x0f) == 0));
break;
case t_INCw:
SET_FLAG(FLAG_OF,(flags.result.w == 0x8000));
SET_FLAG(FLAG_AF,((flags.result.w & 0x0f) == 0));
break;
case t_INCd:
SET_FLAG(FLAG_OF,(flags.result.d == 0x80000000));
SET_FLAG(FLAG_AF,((flags.result.d & 0x0f) == 0));
break;
case t_DECb:
SET_FLAG(FLAG_OF,(flags.result.b == 0x7f));
break;
case t_DECw:
SET_FLAG(FLAG_OF,(flags.result.w == 0x7fff));
break;
case t_DECd:
SET_FLAG(FLAG_OF,(flags.result.d == 0x7fffffff));
break;
case t_NEGb:
SET_FLAG(FLAG_CF,(flags.var1.b!=0));
break;
case t_NEGw:
SET_FLAG(FLAG_CF,(flags.var1.w!=0));
break;
case t_NEGd:
SET_FLAG(FLAG_CF,(flags.var1.d!=0));
break;
case t_DIV:
SET_FLAG(FLAG_CF,false); /* Unkown */
break;
default:
LOG(LOG_ERROR|LOG_CPU,"Unhandled flag type %d",flags.type);
return 0;
}
flags.word=new_flags;
return 0;
}
Bit8u * blah=(Bit8u *)&get_Flags;