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fxinst.cpp
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fxinst.cpp
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/*****************************************************************************\
Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
This file is licensed under the Snes9x License.
For further information, consult the LICENSE file in the root directory.
\*****************************************************************************/
#include "snes9x.h"
#include "fxinst.h"
#include "fxemu.h"
// Set this define if you wish the plot instruction to check for y-pos limits (I don't think it's nessecary)
#define CHECK_LIMITS
/*
Codes used:
rn = a GSU register (r0 - r15)
#n = 4 bit immediate value
#pp = 8 bit immediate value
(yy) = 8 bit word address (0x0000 - 0x01fe)
#xx = 16 bit immediate value
(xx) = 16 bit address (0x0000 - 0xffff)
*/
// 00 - stop - stop GSU execution (and maybe generate an IRQ)
static void fx_stop (void)
{
CF(G);
GSU.vCounter = 0;
GSU.vInstCount = GSU.vCounter;
// Check if we need to generate an IRQ
if (!(GSU.pvRegisters[GSU_CFGR] & 0x80))
SF(IRQ);
GSU.vPlotOptionReg = 0;
GSU.vPipe = 1;
CLRFLAGS;
R15++;
}
// 01 - nop - no operation
static void fx_nop (void)
{
CLRFLAGS;
R15++;
}
// 02 - cache - reintialize GSU cache
static void fx_cache (void)
{
uint32 c = R15 & 0xfff0;
if (GSU.vCacheBaseReg != c || !GSU.bCacheActive)
{
fx_flushCache();
GSU.vCacheBaseReg = c;
GSU.bCacheActive = TRUE;
#if 0
if (c < (0x10000 - 512))
{
const uint8 *t = &ROM(c);
memcpy(GSU.pvCache, t, 512);
}
else
{
const uint8 *t1, t2;
uint32 i = 0x10000 - c;
t1 = &ROM(c);
t2 = &ROM(0);
memcpy(GSU.pvCache, t1, i);
memcpy(&GSU.pvCache[i], t2, 512 - i);
}
#endif
}
CLRFLAGS;
R15++;
}
// 03 - lsr - logic shift right
static void fx_lsr (void)
{
uint32 v;
GSU.vCarry = SREG & 1;
v = USEX16(SREG) >> 1;
R15++;
DREG = v;
GSU.vSign = v;
GSU.vZero = v;
TESTR14;
CLRFLAGS;
}
// 04 - rol - rotate left
static void fx_rol (void)
{
uint32 v = USEX16((SREG << 1) + GSU.vCarry);
GSU.vCarry = (SREG >> 15) & 1;
R15++;
DREG = v;
GSU.vSign = v;
GSU.vZero = v;
TESTR14;
CLRFLAGS;
}
// 05 - bra - branch always
static void fx_bra (void)
{
uint8 v = PIPE;
R15++;
FETCHPIPE;
R15 += SEX8(v);
}
// Branch on condition
#define BRA_COND(cond) \
uint8 v = PIPE; \
R15++; \
FETCHPIPE; \
if (cond) \
R15 += SEX8(v); \
else \
R15++
#define TEST_S (GSU.vSign & 0x8000)
#define TEST_Z (USEX16(GSU.vZero) == 0)
#define TEST_OV (GSU.vOverflow >= 0x8000 || GSU.vOverflow < -0x8000)
#define TEST_CY (GSU.vCarry & 1)
// 06 - blt - branch on less than
static void fx_blt (void)
{
BRA_COND((TEST_S != 0) != (TEST_OV != 0));
}
// 07 - bge - branch on greater or equals
static void fx_bge (void)
{
BRA_COND((TEST_S != 0) == (TEST_OV != 0));
}
// 08 - bne - branch on not equal
static void fx_bne (void)
{
BRA_COND(!TEST_Z);
}
// 09 - beq - branch on equal
static void fx_beq (void)
{
BRA_COND(TEST_Z);
}
// 0a - bpl - branch on plus
static void fx_bpl (void)
{
BRA_COND(!TEST_S);
}
// 0b - bmi - branch on minus
static void fx_bmi (void)
{
BRA_COND(TEST_S);
}
// 0c - bcc - branch on carry clear
static void fx_bcc (void)
{
BRA_COND(!TEST_CY);
}
// 0d - bcs - branch on carry set
static void fx_bcs (void)
{
BRA_COND(TEST_CY);
}
// 0e - bvc - branch on overflow clear
static void fx_bvc (void)
{
BRA_COND(!TEST_OV);
}
// 0f - bvs - branch on overflow set
static void fx_bvs (void)
{
BRA_COND(TEST_OV);
}
// 10-1f - to rn - set register n as destination register
// 10-1f (B) - move rn - move one register to another (if B flag is set)
#define FX_TO(reg) \
if (TF(B)) \
{ \
GSU.avReg[(reg)] = SREG; \
CLRFLAGS; \
} \
else \
GSU.pvDreg = &GSU.avReg[reg]; \
R15++
#define FX_TO_R14(reg) \
if (TF(B)) \
{ \
GSU.avReg[(reg)] = SREG; \
CLRFLAGS; \
READR14; \
} \
else \
GSU.pvDreg = &GSU.avReg[reg]; \
R15++
#define FX_TO_R15(reg) \
if (TF(B)) \
{ \
GSU.avReg[(reg)] = SREG; \
CLRFLAGS; \
} \
else \
{ \
GSU.pvDreg = &GSU.avReg[reg]; \
R15++; \
}
static void fx_to_r0 (void)
{
FX_TO(0);
}
static void fx_to_r1 (void)
{
FX_TO(1);
}
static void fx_to_r2 (void)
{
FX_TO(2);
}
static void fx_to_r3 (void)
{
FX_TO(3);
}
static void fx_to_r4 (void)
{
FX_TO(4);
}
static void fx_to_r5 (void)
{
FX_TO(5);
}
static void fx_to_r6 (void)
{
FX_TO(6);
}
static void fx_to_r7 (void)
{
FX_TO(7);
}
static void fx_to_r8 (void)
{
FX_TO(8);
}
static void fx_to_r9 (void)
{
FX_TO(9);
}
static void fx_to_r10 (void)
{
FX_TO(10);
}
static void fx_to_r11 (void)
{
FX_TO(11);
}
static void fx_to_r12 (void)
{
FX_TO(12);
}
static void fx_to_r13 (void)
{
FX_TO(13);
}
static void fx_to_r14 (void)
{
FX_TO_R14(14);
}
static void fx_to_r15 (void)
{
FX_TO_R15(15);
}
// 20-2f - to rn - set register n as source and destination register
#define FX_WITH(reg) \
SF(B); \
GSU.pvSreg = GSU.pvDreg = &GSU.avReg[reg]; \
R15++
static void fx_with_r0 (void)
{
FX_WITH(0);
}
static void fx_with_r1 (void)
{
FX_WITH(1);
}
static void fx_with_r2 (void)
{
FX_WITH(2);
}
static void fx_with_r3 (void)
{
FX_WITH(3);
}
static void fx_with_r4 (void)
{
FX_WITH(4);
}
static void fx_with_r5 (void)
{
FX_WITH(5);
}
static void fx_with_r6 (void)
{
FX_WITH(6);
}
static void fx_with_r7 (void)
{
FX_WITH(7);
}
static void fx_with_r8 (void)
{
FX_WITH(8);
}
static void fx_with_r9 (void)
{
FX_WITH(9);
}
static void fx_with_r10 (void)
{
FX_WITH(10);
}
static void fx_with_r11 (void)
{
FX_WITH(11);
}
static void fx_with_r12 (void)
{
FX_WITH(12);
}
static void fx_with_r13 (void)
{
FX_WITH(13);
}
static void fx_with_r14 (void)
{
FX_WITH(14);
}
static void fx_with_r15 (void)
{
FX_WITH(15);
}
// 30-3b - stw (rn) - store word
#define FX_STW(reg) \
GSU.vLastRamAdr = GSU.avReg[reg]; \
RAM(GSU.avReg[reg]) = (uint8) SREG; \
RAM(GSU.avReg[reg] ^ 1) = (uint8) (SREG >> 8); \
CLRFLAGS; \
R15++
static void fx_stw_r0 (void)
{
FX_STW(0);
}
static void fx_stw_r1 (void)
{
FX_STW(1);
}
static void fx_stw_r2 (void)
{
FX_STW(2);
}
static void fx_stw_r3 (void)
{
FX_STW(3);
}
static void fx_stw_r4 (void)
{
FX_STW(4);
}
static void fx_stw_r5 (void)
{
FX_STW(5);
}
static void fx_stw_r6 (void)
{
FX_STW(6);
}
static void fx_stw_r7 (void)
{
FX_STW(7);
}
static void fx_stw_r8 (void)
{
FX_STW(8);
}
static void fx_stw_r9 (void)
{
FX_STW(9);
}
static void fx_stw_r10 (void)
{
FX_STW(10);
}
static void fx_stw_r11 (void)
{
FX_STW(11);
}
// 30-3b (ALT1) - stb (rn) - store byte
#define FX_STB(reg) \
GSU.vLastRamAdr = GSU.avReg[reg]; \
RAM(GSU.avReg[reg]) = (uint8) SREG; \
CLRFLAGS; \
R15++
static void fx_stb_r0 (void)
{
FX_STB(0);
}
static void fx_stb_r1 (void)
{
FX_STB(1);
}
static void fx_stb_r2 (void)
{
FX_STB(2);
}
static void fx_stb_r3 (void)
{
FX_STB(3);
}
static void fx_stb_r4 (void)
{
FX_STB(4);
}
static void fx_stb_r5 (void)
{
FX_STB(5);
}
static void fx_stb_r6 (void)
{
FX_STB(6);
}
static void fx_stb_r7 (void)
{
FX_STB(7);
}
static void fx_stb_r8 (void)
{
FX_STB(8);
}
static void fx_stb_r9 (void)
{
FX_STB(9);
}
static void fx_stb_r10 (void)
{
FX_STB(10);
}
static void fx_stb_r11 (void)
{
FX_STB(11);
}
// 3c - loop - decrement loop counter, and branch on not zero
static void fx_loop (void)
{
GSU.vSign = GSU.vZero = --R12;
if ((uint16) R12 != 0)
R15 = R13;
else
R15++;
CLRFLAGS;
}
// 3d - alt1 - set alt1 mode
static void fx_alt1 (void)
{
SF(ALT1);
CF(B);
R15++;
}
// 3e - alt2 - set alt2 mode
static void fx_alt2 (void)
{
SF(ALT2);
CF(B);
R15++;
}
// 3f - alt3 - set alt3 mode
static void fx_alt3 (void)
{
SF(ALT1);
SF(ALT2);
CF(B);
R15++;
}
// 40-4b - ldw (rn) - load word from RAM
#define FX_LDW(reg) \
uint32 v; \
GSU.vLastRamAdr = GSU.avReg[reg]; \
v = (uint32) RAM(GSU.avReg[reg]); \
v |= ((uint32) RAM(GSU.avReg[reg] ^ 1)) << 8; \
R15++; \
DREG = v; \
TESTR14; \
CLRFLAGS
static void fx_ldw_r0 (void)
{
FX_LDW(0);
}
static void fx_ldw_r1 (void)
{
FX_LDW(1);
}
static void fx_ldw_r2 (void)
{
FX_LDW(2);
}
static void fx_ldw_r3 (void)
{
FX_LDW(3);
}
static void fx_ldw_r4 (void)
{
FX_LDW(4);
}
static void fx_ldw_r5 (void)
{
FX_LDW(5);
}
static void fx_ldw_r6 (void)
{
FX_LDW(6);
}
static void fx_ldw_r7 (void)
{
FX_LDW(7);
}
static void fx_ldw_r8 (void)
{
FX_LDW(8);
}
static void fx_ldw_r9 (void)
{
FX_LDW(9);
}
static void fx_ldw_r10 (void)
{
FX_LDW(10);
}
static void fx_ldw_r11 (void)
{
FX_LDW(11);
}
// 40-4b (ALT1) - ldb (rn) - load byte
#define FX_LDB(reg) \
uint32 v; \
GSU.vLastRamAdr = GSU.avReg[reg]; \
v = (uint32) RAM(GSU.avReg[reg]); \
R15++; \
DREG = v; \
TESTR14; \
CLRFLAGS
static void fx_ldb_r0 (void)
{
FX_LDB(0);
}
static void fx_ldb_r1 (void)
{
FX_LDB(1);
}
static void fx_ldb_r2 (void)
{
FX_LDB(2);
}
static void fx_ldb_r3 (void)
{
FX_LDB(3);
}
static void fx_ldb_r4 (void)
{
FX_LDB(4);
}
static void fx_ldb_r5 (void)
{
FX_LDB(5);
}
static void fx_ldb_r6 (void)
{
FX_LDB(6);
}
static void fx_ldb_r7 (void)
{
FX_LDB(7);
}
static void fx_ldb_r8 (void)
{
FX_LDB(8);
}
static void fx_ldb_r9 (void)
{
FX_LDB(9);
}
static void fx_ldb_r10 (void)
{
FX_LDB(10);
}
static void fx_ldb_r11 (void)
{
FX_LDB(11);
}
// 4c - plot - plot pixel with R1, R2 as x, y and the color register as the color
static void fx_plot_2bit (void)
{
uint32 x = USEX8(R1);
uint32 y = USEX8(R2);
uint8 *a;
uint8 v, c;
R15++;
CLRFLAGS;
R1++;
#ifdef CHECK_LIMITS
if (y >= GSU.vScreenHeight)
return;
#endif
if (!(GSU.vPlotOptionReg & 0x01) && !(COLR & 0xf))
return;
if (GSU.vPlotOptionReg & 0x02)
c = ((x ^ y) & 1) ? (uint8) (GSU.vColorReg >> 4) : (uint8) GSU.vColorReg;
else
c = (uint8) GSU.vColorReg;
a = GSU.apvScreen[y >> 3] + GSU.x[x >> 3] + ((y & 7) << 1);
v = 128 >> (x & 7);
if (c & 0x01)
a[0] |= v;
else
a[0] &= ~v;
if (c & 0x02)
a[1] |= v;
else
a[1] &= ~v;
}
// 4c (ALT1) - rpix - read color of the pixel with R1, R2 as x, y
static void fx_rpix_2bit (void)
{
uint32 x = USEX8(R1);
uint32 y = USEX8(R2);
uint8 *a;
uint8 v;
R15++;
CLRFLAGS;
#ifdef CHECK_LIMITS
if (y >= GSU.vScreenHeight)
return;
#endif
a = GSU.apvScreen[y >> 3] + GSU.x[x >> 3] + ((y & 7) << 1);
v = 128 >> (x & 7);
DREG = 0;
DREG |= ((uint32) ((a[0] & v) != 0)) << 0;
DREG |= ((uint32) ((a[1] & v) != 0)) << 1;
TESTR14;
}
// 4c - plot - plot pixel with R1, R2 as x, y and the color register as the color
static void fx_plot_4bit (void)
{
uint32 x = USEX8(R1);
uint32 y = USEX8(R2);
uint8 *a;
uint8 v, c;
R15++;
CLRFLAGS;
R1++;
#ifdef CHECK_LIMITS
if (y >= GSU.vScreenHeight)
return;
#endif
if (!(GSU.vPlotOptionReg & 0x01) && !(COLR & 0xf))
return;
if (GSU.vPlotOptionReg & 0x02)
c = ((x ^ y) & 1) ? (uint8) (GSU.vColorReg >> 4) : (uint8) GSU.vColorReg;
else
c = (uint8) GSU.vColorReg;
a = GSU.apvScreen[y >> 3] + GSU.x[x >> 3] + ((y & 7) << 1);
v = 128 >> (x & 7);
if (c & 0x01)
a[0x00] |= v;
else
a[0x00] &= ~v;
if (c & 0x02)
a[0x01] |= v;
else
a[0x01] &= ~v;
if (c & 0x04)
a[0x10] |= v;
else
a[0x10] &= ~v;
if (c & 0x08)
a[0x11] |= v;
else
a[0x11] &= ~v;
}
// 4c (ALT1) - rpix - read color of the pixel with R1, R2 as x, y
static void fx_rpix_4bit (void)
{
uint32 x = USEX8(R1);
uint32 y = USEX8(R2);
uint8 *a;
uint8 v;
R15++;
CLRFLAGS;
#ifdef CHECK_LIMITS
if (y >= GSU.vScreenHeight)
return;
#endif
a = GSU.apvScreen[y >> 3] + GSU.x[x >> 3] + ((y & 7) << 1);
v = 128 >> (x & 7);
DREG = 0;
DREG |= ((uint32) ((a[0x00] & v) != 0)) << 0;
DREG |= ((uint32) ((a[0x01] & v) != 0)) << 1;
DREG |= ((uint32) ((a[0x10] & v) != 0)) << 2;
DREG |= ((uint32) ((a[0x11] & v) != 0)) << 3;
TESTR14;
}
// 4c - plot - plot pixel with R1, R2 as x, y and the color register as the color
static void fx_plot_8bit (void)
{
uint32 x = USEX8(R1);
uint32 y = USEX8(R2);
uint8 *a;
uint8 v, c;
R15++;
CLRFLAGS;
R1++;
#ifdef CHECK_LIMITS
if (y >= GSU.vScreenHeight)
return;
#endif
c = (uint8) GSU.vColorReg;
if (!(GSU.vPlotOptionReg & 0x10))
{
if (!(GSU.vPlotOptionReg & 0x01) && (!c || ((GSU.vPlotOptionReg & 0x08) && !(c & 0xf))))
return;
}
else
if (!(GSU.vPlotOptionReg & 0x01) && !c)
return;
a = GSU.apvScreen[y >> 3] + GSU.x[x >> 3] + ((y & 7) << 1);
v = 128 >> (x & 7);
if (c & 0x01)
a[0x00] |= v;
else
a[0x00] &= ~v;
if (c & 0x02)
a[0x01] |= v;
else
a[0x01] &= ~v;
if (c & 0x04)
a[0x10] |= v;
else
a[0x10] &= ~v;
if (c & 0x08)
a[0x11] |= v;
else
a[0x11] &= ~v;
if (c & 0x10)
a[0x20] |= v;
else
a[0x20] &= ~v;
if (c & 0x20)
a[0x21] |= v;
else
a[0x21] &= ~v;
if (c & 0x40)
a[0x30] |= v;
else
a[0x30] &= ~v;
if (c & 0x80)
a[0x31] |= v;
else
a[0x31] &= ~v;
}
// 4c (ALT1) - rpix - read color of the pixel with R1, R2 as x, y
static void fx_rpix_8bit (void)
{
uint32 x = USEX8(R1);
uint32 y = USEX8(R2);
uint8 *a;
uint8 v;
R15++;
CLRFLAGS;
#ifdef CHECK_LIMITS
if (y >= GSU.vScreenHeight)
return;
#endif
a = GSU.apvScreen[y >> 3] + GSU.x[x >> 3] + ((y & 7) << 1);
v = 128 >> (x & 7);
DREG = 0;
DREG |= ((uint32) ((a[0x00] & v) != 0)) << 0;
DREG |= ((uint32) ((a[0x01] & v) != 0)) << 1;
DREG |= ((uint32) ((a[0x10] & v) != 0)) << 2;
DREG |= ((uint32) ((a[0x11] & v) != 0)) << 3;
DREG |= ((uint32) ((a[0x20] & v) != 0)) << 4;
DREG |= ((uint32) ((a[0x21] & v) != 0)) << 5;
DREG |= ((uint32) ((a[0x30] & v) != 0)) << 6;
DREG |= ((uint32) ((a[0x31] & v) != 0)) << 7;
GSU.vZero = DREG;
TESTR14;
}
// 4c - plot - plot pixel with R1, R2 as x, y and the color register as the color
static void fx_plot_obj (void)
{
#ifdef DEBUGGER
fprintf(stderr, "ERROR fx_plot_obj called\n");
#endif
}
// 4c (ALT1) - rpix - read color of the pixel with R1, R2 as x, y
static void fx_rpix_obj (void)
{
#ifdef DEBUGGER
fprintf(stderr, "ERROR fx_rpix_obj called\n");
#endif
}
// 4d - swap - swap upper and lower byte of a register
static void fx_swap (void)
{
uint8 c = (uint8) SREG;
uint8 d = (uint8) (SREG >> 8);
uint32 v = (((uint32) c) << 8) | ((uint32) d);
R15++;
DREG = v;
GSU.vSign = v;
GSU.vZero = v;
TESTR14;
CLRFLAGS;
}
// 4e - color - copy source register to color register
static void fx_color (void)
{
uint8 c = (uint8) SREG;
if (GSU.vPlotOptionReg & 0x04)
c = (c & 0xf0) | (c >> 4);
if (GSU.vPlotOptionReg & 0x08)
{
GSU.vColorReg &= 0xf0;
GSU.vColorReg |= c & 0x0f;
}
else
GSU.vColorReg = USEX8(c);
CLRFLAGS;
R15++;
}
// 4e (ALT1) - cmode - set plot option register
static void fx_cmode (void)
{