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SH2DRC: add SUBV, replace ADDV with C version as a precaution. (Fixes most of Mantis #2026, except the part which is a separate bug).

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This commit is contained in:
R. Belmont 2008-07-28 23:12:47 +00:00
parent 6d998d26ed
commit 76d5ed12a3
1 changed files with 95 additions and 7 deletions
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102
src/emu/cpu/sh2/sh2drc.c
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@ -539,6 +539,92 @@ static void cfunc_DIV1(void *param)
sh2->sr &= ~T;
}
/*-------------------------------------------------
cfunc_ADDV - implementation of ADDV Rm,Rn
-------------------------------------------------*/
static void cfunc_ADDV(void *param)
{
INT32 dest, src, ans;
UINT16 *opptr, opcode;
int n, m;
// recover the opcode
opptr = (UINT16 *)param;
opcode = *opptr;
// extract the operands
n = Rn;
m = Rm;
if ((INT32) sh2->r[n] >= 0)
dest = 0;
else
dest = 1;
if ((INT32) sh2->r[m] >= 0)
src = 0;
else
src = 1;
src += dest;
sh2->r[n] += sh2->r[m];
if ((INT32) sh2->r[n] >= 0)
ans = 0;
else
ans = 1;
ans += dest;
if (src == 0 || src == 2)
{
if (ans == 1)
sh2->sr |= T;
else
sh2->sr &= ~T;
}
else
sh2->sr &= ~T;
}
/*-------------------------------------------------
cfunc_SUBV - implementation of SUBV Rm,Rn
-------------------------------------------------*/
static void cfunc_SUBV(void *param)
{
INT32 dest, src, ans;
UINT16 *opptr, opcode;
int n, m;
// recover the opcode
opptr = (UINT16 *)param;
opcode = *opptr;
// extract the operands
n = Rn;
m = Rm;
if ((INT32) sh2->r[n] >= 0)
dest = 0;
else
dest = 1;
if ((INT32) sh2->r[m] >= 0)
src = 0;
else
src = 1;
src += dest;
sh2->r[n] -= sh2->r[m];
if ((INT32) sh2->r[n] >= 0)
ans = 0;
else
ans = 1;
ans += dest;
if (src == 1)
{
if (ans == 1)
sh2->sr |= T;
else
sh2->sr &= ~T;
}
else
sh2->sr &= ~T;
}
/*-------------------------------------------------
sh2_init - initialize the processor
-------------------------------------------------*/
@ -2139,6 +2225,11 @@ static int generate_group_3(drcuml_block *block, compiler_state *compiler, const
break;
case 11: // SUBV(Rm, Rn);
save_fast_iregs(block);
UML_CALLC(block, cfunc_SUBV, desc->opptr.w);
load_fast_iregs(block);
return TRUE;
break;
case 14: // ADDC(Rm, Rn);
@ -2155,13 +2246,10 @@ static int generate_group_3(drcuml_block *block, compiler_state *compiler, const
break;
case 15: // ADDV(Rm, Rn);
UML_AND(block, MEM(&sh2->sr), MEM(&sh2->sr), IMM(~T)); // and sr, sr, ~T (clear the T bit)
UML_ADD(block, R32(Rn), R32(Rn), R32(Rm)); // add Rn, Rn, Rm
UML_JMPc(block, IF_NV, compiler->labelnum); // jnc labelnum
UML_OR(block, MEM(&sh2->sr), MEM(&sh2->sr), IMM(T)); // or sr, sr, T
UML_LABEL(block, compiler->labelnum++); // labelnum:
save_fast_iregs(block);
UML_CALLC(block, cfunc_ADDV, desc->opptr.w);
load_fast_iregs(block);
return TRUE;
break;
}