initial upstream import

[drnoksnes] / cpuexec.h

diff --git a/cpuexec.h b/cpuexec.h
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+++ b/cpuexec.h
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+/*
+ * Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
+ *
+ * (c) Copyright 1996 - 2001 Gary Henderson (gary.henderson@ntlworld.com) and
+ *                           Jerremy Koot (jkoot@snes9x.com)
+ *
+ * Super FX C emulator code 
+ * (c) Copyright 1997 - 1999 Ivar (ivar@snes9x.com) and
+ *                           Gary Henderson.
+ * Super FX assembler emulator code (c) Copyright 1998 zsKnight and _Demo_.
+ *
+ * DSP1 emulator code (c) Copyright 1998 Ivar, _Demo_ and Gary Henderson.
+ * C4 asm and some C emulation code (c) Copyright 2000 zsKnight and _Demo_.
+ * C4 C code (c) Copyright 2001 Gary Henderson (gary.henderson@ntlworld.com).
+ *
+ * DOS port code contains the works of other authors. See headers in
+ * individual files.
+ *
+ * Snes9x homepage: http://www.snes9x.com
+ *
+ * Permission to use, copy, modify and distribute Snes9x in both binary and
+ * source form, for non-commercial purposes, is hereby granted without fee,
+ * providing that this license information and copyright notice appear with
+ * all copies and any derived work.
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event shall the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Snes9x is freeware for PERSONAL USE only. Commercial users should
+ * seek permission of the copyright holders first. Commercial use includes
+ * charging money for Snes9x or software derived from Snes9x.
+ *
+ * The copyright holders request that bug fixes and improvements to the code
+ * should be forwarded to them so everyone can benefit from the modifications
+ * in future versions.
+ *
+ * Super NES and Super Nintendo Entertainment System are trademarks of
+ * Nintendo Co., Limited and its subsidiary companies.
+ */
+#ifndef _CPUEXEC_H_
+#define _CPUEXEC_H_
+#include "ppu.h"
+#include "memmap.h"
+#include "65c816.h"
+
+#define DO_HBLANK_CHECK() \
+    if (CPU.Cycles >= CPU.NextEvent) \
+       S9xDoHBlankProcessing ();
+
+struct SOpcodes {
+#ifdef __WIN32__
+       void (__cdecl *S9xOpcode)( void);
+#else
+       void (*S9xOpcode)( void);
+#endif
+};
+
+struct SICPU
+{
+/*
+    uint8  *Speed;
+    struct SOpcodes *S9xOpcodes;
+    uint8  _Carry;
+    uint8  _Zero;
+    uint8  _Negative;
+    uint8  _Overflow;
+*/
+       bool8  CPUExecuting;
+    uint32 ShiftedPB;
+    uint32 ShiftedDB;
+    uint32 Frame;
+    uint32 Scanline;
+    uint32 FrameAdvanceCount;
+};
+
+START_EXTERN_C
+void S9xMainLoop (void);
+void S9xReset (void);
+void S9xDoHBlankProcessing ();
+void S9xClearIRQ (uint32);
+void S9xSetIRQ (uint32);
+
+extern struct SOpcodes S9xOpcodesM1X1 [256];
+extern struct SOpcodes S9xOpcodesM1X0 [256];
+extern struct SOpcodes S9xOpcodesM0X1 [256];
+extern struct SOpcodes S9xOpcodesM0X0 [256];
+
+#ifndef VAR_CYCLES
+extern uint8 S9xE1M1X1 [256];
+extern uint8 S9xE0M1X0 [256];
+extern uint8 S9xE0M1X1 [256];
+extern uint8 S9xE0M0X0 [256];
+extern uint8 S9xE0M0X1 [256];
+#endif
+
+extern struct SICPU ICPU;
+END_EXTERN_C
+
+STATIC inline void CLEAR_IRQ_SOURCE (uint32 M)
+{
+    CPU.IRQActive &= ~M;
+    if (!CPU.IRQActive)
+       CPU.Flags &= ~IRQ_PENDING_FLAG;
+}
+
+#if 0
+STATIC inline void S9xUnpackStatus()
+{
+    ICPU._Zero = (Registers.PL & Zero) == 0;
+    ICPU._Negative = (Registers.PL & Negative);
+    ICPU._Carry = (Registers.PL & Carry);
+    ICPU._Overflow = (Registers.PL & Overflow) >> 6;
+}
+
+STATIC inline void S9xPackStatus()
+{
+    Registers.PL &= ~(Zero | Negative | Carry | Overflow);
+    Registers.PL |= ICPU._Carry | ((ICPU._Zero == 0) << 1) |
+                   (ICPU._Negative & 0x80) | (ICPU._Overflow << 6);
+}
+
+STATIC inline void S9xFixCycles ()
+{
+    if (CheckEmulation ())
+    {
+#ifndef VAR_CYCLES
+       ICPU.Speed = S9xE1M1X1;
+#endif
+       ICPU.S9xOpcodes = S9xOpcodesM1X1;
+    }
+    else
+    if (CheckMemory ())
+    {
+       if (CheckIndex ())
+       {
+#ifndef VAR_CYCLES
+           ICPU.Speed = S9xE0M1X1;
+#endif
+           ICPU.S9xOpcodes = S9xOpcodesM1X1;
+       }
+       else
+       {
+#ifndef VAR_CYCLES
+           ICPU.Speed = S9xE0M1X0;
+#endif
+           ICPU.S9xOpcodes = S9xOpcodesM1X0;
+       }
+    }
+    else
+    {
+       if (CheckIndex ())
+       {
+#ifndef VAR_CYCLES
+           ICPU.Speed = S9xE0M0X1;
+#endif
+           ICPU.S9xOpcodes = S9xOpcodesM0X1;
+       }
+       else
+       {
+#ifndef VAR_CYCLES
+           ICPU.Speed = S9xE0M0X0;
+#endif
+           ICPU.S9xOpcodes = S9xOpcodesM0X0;
+       }
+    }
+}
+#endif
+
+STATIC inline void S9xReschedule ()
+{
+    uint8 which;
+    long max;
+    
+    if (CPU.WhichEvent == HBLANK_START_EVENT ||
+       CPU.WhichEvent == HTIMER_AFTER_EVENT)
+    {
+       which = HBLANK_END_EVENT;
+       max = Settings.H_Max;
+    }
+    else
+    {
+       which = HBLANK_START_EVENT;
+       max = Settings.HBlankStart;
+    }
+
+    if (PPU.HTimerEnabled &&
+        (long) PPU.HTimerPosition < max &&
+       (long) PPU.HTimerPosition > CPU.NextEvent &&
+       (!PPU.VTimerEnabled ||
+        (PPU.VTimerEnabled && CPU.V_Counter == PPU.IRQVBeamPos)))
+    {
+       which = (long) PPU.HTimerPosition < Settings.HBlankStart ?
+                       HTIMER_BEFORE_EVENT : HTIMER_AFTER_EVENT;
+       max = PPU.HTimerPosition;
+    }
+    CPU.NextEvent = max;
+    CPU.WhichEvent = which;
+}
+
+#endif