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m68kcpu.h
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m68kcpu.h
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/* ======================================================================== */
/* ========================= LICENSING & COPYRIGHT ======================== */
/* ======================================================================== */
/*
* MUSASHI
* Version 3.4
*
* A portable Motorola M680x0 processor emulation engine.
* Copyright 1998-2001 Karl Stenerud. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef M68KCPU__HEADER
#define M68KCPU__HEADER
#include "m68k.h"
#include <limits.h>
#if M68K_EMULATE_ADDRESS_ERROR
#include <setjmp.h>
#endif /* M68K_EMULATE_ADDRESS_ERROR */
/* ======================================================================== */
/* ==================== ARCHITECTURE-DEPENDANT DEFINES ==================== */
/* ======================================================================== */
/* Check for > 32bit sizes */
#if UINT_MAX > 0xffffffff
#define M68K_INT_GT_32_BIT 1
#else
#define M68K_INT_GT_32_BIT 0
#endif
/* Data types used in this emulation core */
#undef sint8
#undef sint16
#undef sint32
#undef sint64
#undef uint8
#undef uint16
#undef uint32
#undef uint64
#undef sint
#undef uint
#define sint8 signed char /* ASG: changed from char to signed char */
#define sint16 signed short
#define sint32 signed long
#define uint8 unsigned char
#define uint16 unsigned short
#define uint32 unsigned long
/* signed and unsigned int must be at least 32 bits wide */
#define sint signed int
#define uint unsigned int
#if M68K_USE_64_BIT
#define sint64 signed long long
#define uint64 unsigned long long
#else
#define sint64 sint32
#define uint64 uint32
#endif /* M68K_USE_64_BIT */
/* Allow for architectures that don't have 8-bit sizes */
#if UCHAR_MAX == 0xff
#define MAKE_INT_8(A) (sint8)(A)
#else
#undef sint8
#define sint8 signed int
#undef uint8
#define uint8 unsigned int
INLINE sint MAKE_INT_8(uint value)
{
return (value & 0x80) ? value | ~0xff : value & 0xff;
}
#endif /* UCHAR_MAX == 0xff */
/* Allow for architectures that don't have 16-bit sizes */
#if USHRT_MAX == 0xffff
#define MAKE_INT_16(A) (sint16)(A)
#else
#undef sint16
#define sint16 signed int
#undef uint16
#define uint16 unsigned int
INLINE sint MAKE_INT_16(uint value)
{
return (value & 0x8000) ? value | ~0xffff : value & 0xffff;
}
#endif /* USHRT_MAX == 0xffff */
/* Allow for architectures that don't have 32-bit sizes */
#if ULONG_MAX == 0xffffffff
#define MAKE_INT_32(A) (sint32)(A)
#else
#undef sint32
#define sint32 signed int
#undef uint32
#define uint32 unsigned int
INLINE sint MAKE_INT_32(uint value)
{
return (value & 0x80000000) ? value | ~0xffffffff : value & 0xffffffff;
}
#endif /* ULONG_MAX == 0xffffffff */
/* ======================================================================== */
/* ============================ GENERAL DEFINES =========================== */
/* ======================================================================== */
/* Exception Vectors handled by emulation */
#define EXCEPTION_BUS_ERROR 2 /* This one is not emulated! */
#define EXCEPTION_ADDRESS_ERROR 3 /* This one is partially emulated (doesn't stack a proper frame yet) */
#define EXCEPTION_ILLEGAL_INSTRUCTION 4
#define EXCEPTION_ZERO_DIVIDE 5
#define EXCEPTION_CHK 6
#define EXCEPTION_TRAPV 7
#define EXCEPTION_PRIVILEGE_VIOLATION 8
#define EXCEPTION_TRACE 9
#define EXCEPTION_1010 10
#define EXCEPTION_1111 11
#define EXCEPTION_FORMAT_ERROR 14
#define EXCEPTION_UNINITIALIZED_INTERRUPT 15
#define EXCEPTION_SPURIOUS_INTERRUPT 24
#define EXCEPTION_INTERRUPT_AUTOVECTOR 24
#define EXCEPTION_TRAP_BASE 32
/* Function codes set by CPU during data/address bus activity */
#define FUNCTION_CODE_USER_DATA 1
#define FUNCTION_CODE_USER_PROGRAM 2
#define FUNCTION_CODE_SUPERVISOR_DATA 5
#define FUNCTION_CODE_SUPERVISOR_PROGRAM 6
#define FUNCTION_CODE_CPU_SPACE 7
/* CPU types for deciding what to emulate */
#define CPU_TYPE_000 1
#define CPU_TYPE_010 2
#define CPU_TYPE_EC020 4
#define CPU_TYPE_020 8
/* Different ways to stop the CPU */
#define STOP_LEVEL_STOP 1
#define STOP_LEVEL_HALT 2
/* Used for 68000 address error processing */
#define INSTRUCTION_YES 0
#define INSTRUCTION_NO 0x08
#define MODE_READ 0x10
#define MODE_WRITE 0
#define RUN_MODE_NORMAL 0
#define RUN_MODE_BERR_AERR_RESET 1
#ifndef NULL
#define NULL ((void*)0)
#endif
/* ======================================================================== */
/* ================================ MACROS ================================ */
/* ======================================================================== */
/* ---------------------------- General Macros ---------------------------- */
/* Bit Isolation Macros */
#define BIT_0(A) ((A) & 0x00000001)
#define BIT_1(A) ((A) & 0x00000002)
#define BIT_2(A) ((A) & 0x00000004)
#define BIT_3(A) ((A) & 0x00000008)
#define BIT_4(A) ((A) & 0x00000010)
#define BIT_5(A) ((A) & 0x00000020)
#define BIT_6(A) ((A) & 0x00000040)
#define BIT_7(A) ((A) & 0x00000080)
#define BIT_8(A) ((A) & 0x00000100)
#define BIT_9(A) ((A) & 0x00000200)
#define BIT_A(A) ((A) & 0x00000400)
#define BIT_B(A) ((A) & 0x00000800)
#define BIT_C(A) ((A) & 0x00001000)
#define BIT_D(A) ((A) & 0x00002000)
#define BIT_E(A) ((A) & 0x00004000)
#define BIT_F(A) ((A) & 0x00008000)
#define BIT_10(A) ((A) & 0x00010000)
#define BIT_11(A) ((A) & 0x00020000)
#define BIT_12(A) ((A) & 0x00040000)
#define BIT_13(A) ((A) & 0x00080000)
#define BIT_14(A) ((A) & 0x00100000)
#define BIT_15(A) ((A) & 0x00200000)
#define BIT_16(A) ((A) & 0x00400000)
#define BIT_17(A) ((A) & 0x00800000)
#define BIT_18(A) ((A) & 0x01000000)
#define BIT_19(A) ((A) & 0x02000000)
#define BIT_1A(A) ((A) & 0x04000000)
#define BIT_1B(A) ((A) & 0x08000000)
#define BIT_1C(A) ((A) & 0x10000000)
#define BIT_1D(A) ((A) & 0x20000000)
#define BIT_1E(A) ((A) & 0x40000000)
#define BIT_1F(A) ((A) & 0x80000000)
/* Get the most significant bit for specific sizes */
#define GET_MSB_8(A) ((A) & 0x80)
#define GET_MSB_9(A) ((A) & 0x100)
#define GET_MSB_16(A) ((A) & 0x8000)
#define GET_MSB_17(A) ((A) & 0x10000)
#define GET_MSB_32(A) ((A) & 0x80000000)
#if M68K_USE_64_BIT
#define GET_MSB_33(A) ((A) & 0x100000000)
#endif /* M68K_USE_64_BIT */
/* Isolate nibbles */
#define LOW_NIBBLE(A) ((A) & 0x0f)
#define HIGH_NIBBLE(A) ((A) & 0xf0)
/* These are used to isolate 8, 16, and 32 bit sizes */
#define MASK_OUT_ABOVE_2(A) ((A) & 3)
#define MASK_OUT_ABOVE_8(A) ((A) & 0xff)
#define MASK_OUT_ABOVE_16(A) ((A) & 0xffff)
#define MASK_OUT_BELOW_2(A) ((A) & ~3)
#define MASK_OUT_BELOW_8(A) ((A) & ~0xff)
#define MASK_OUT_BELOW_16(A) ((A) & ~0xffff)
/* No need to mask if we are 32 bit */
#if M68K_INT_GT_32_BIT || M68K_USE_64_BIT
#define MASK_OUT_ABOVE_32(A) ((A) & 0xffffffff)
#define MASK_OUT_BELOW_32(A) ((A) & ~0xffffffff)
#else
#define MASK_OUT_ABOVE_32(A) (A)
#define MASK_OUT_BELOW_32(A) 0
#endif /* M68K_INT_GT_32_BIT || M68K_USE_64_BIT */
/* Simulate address lines of 68k family */
#define ADDRESS_68K(A) ((A)&CPU_ADDRESS_MASK)
/* Shift & Rotate Macros. */
#define LSL(A, C) ((A) << (C))
#define LSR(A, C) ((A) >> (C))
/* Some > 32-bit optimizations */
#if M68K_INT_GT_32_BIT
/* Shift left and right */
#define LSR_32(A, C) ((A) >> (C))
#define LSL_32(A, C) ((A) << (C))
#else
/* We have to do this because the morons at ANSI decided that shifts
* by >= data size are undefined.
*/
#define LSR_32(A, C) ((C) < 32 ? (A) >> (C) : 0)
#define LSL_32(A, C) ((C) < 32 ? (A) << (C) : 0)
#endif /* M68K_INT_GT_32_BIT */
#if M68K_USE_64_BIT
#define LSL_32_64(A, C) ((A) << (C))
#define LSR_32_64(A, C) ((A) >> (C))
#define ROL_33_64(A, C) (LSL_32_64(A, C) | LSR_32_64(A, 33-(C)))
#define ROR_33_64(A, C) (LSR_32_64(A, C) | LSL_32_64(A, 33-(C)))
#endif /* M68K_USE_64_BIT */
#define ROL_8(A, C) MASK_OUT_ABOVE_8(LSL(A, C) | LSR(A, 8-(C)))
#define ROL_9(A, C) (LSL(A, C) | LSR(A, 9-(C)))
#define ROL_16(A, C) MASK_OUT_ABOVE_16(LSL(A, C) | LSR(A, 16-(C)))
#define ROL_17(A, C) (LSL(A, C) | LSR(A, 17-(C)))
#define ROL_32(A, C) MASK_OUT_ABOVE_32(LSL_32(A, C) | LSR_32(A, 32-(C)))
#define ROL_33(A, C) (LSL_32(A, C) | LSR_32(A, 33-(C)))
#define ROR_8(A, C) MASK_OUT_ABOVE_8(LSR(A, C) | LSL(A, 8-(C)))
#define ROR_9(A, C) (LSR(A, C) | LSL(A, 9-(C)))
#define ROR_16(A, C) MASK_OUT_ABOVE_16(LSR(A, C) | LSL(A, 16-(C)))
#define ROR_17(A, C) (LSR(A, C) | LSL(A, 17-(C)))
#define ROR_32(A, C) MASK_OUT_ABOVE_32(LSR_32(A, C) | LSL_32(A, 32-(C)))
#define ROR_33(A, C) (LSR_32(A, C) | LSL_32(A, 33-(C)))
/* ------------------------------ CPU Access ------------------------------ */
/* Access the CPU registers */
#define CPU_TYPE m68ki_cpu.cpu_type
#define REG_DA m68ki_cpu.dar /* easy access to data and address regs */
#define REG_D m68ki_cpu.dar
#define REG_A (m68ki_cpu.dar+8)
#define REG_PPC m68ki_cpu.ppc
#define REG_PC m68ki_cpu.pc
#define REG_SP_BASE m68ki_cpu.sp
#define REG_USP m68ki_cpu.sp[0]
#define REG_ISP m68ki_cpu.sp[4]
#define REG_MSP m68ki_cpu.sp[6]
#define REG_SP m68ki_cpu.dar[15]
#define REG_VBR m68ki_cpu.vbr
#define REG_SFC m68ki_cpu.sfc
#define REG_DFC m68ki_cpu.dfc
#define REG_CACR m68ki_cpu.cacr
#define REG_CAAR m68ki_cpu.caar
#define REG_IR m68ki_cpu.ir
#define FLAG_T1 m68ki_cpu.t1_flag
#define FLAG_T0 m68ki_cpu.t0_flag
#define FLAG_S m68ki_cpu.s_flag
#define FLAG_M m68ki_cpu.m_flag
#define FLAG_X m68ki_cpu.x_flag
#define FLAG_N m68ki_cpu.n_flag
#define FLAG_Z m68ki_cpu.not_z_flag
#define FLAG_V m68ki_cpu.v_flag
#define FLAG_C m68ki_cpu.c_flag
#define FLAG_INT_MASK m68ki_cpu.int_mask
#define CPU_INT_LEVEL m68ki_cpu.int_level /* ASG: changed from CPU_INTS_PENDING */
#define CPU_INT_CYCLES m68ki_cpu.int_cycles /* ASG */
#define CPU_STOPPED m68ki_cpu.stopped
#define CPU_PREF_ADDR m68ki_cpu.pref_addr
#define CPU_PREF_DATA m68ki_cpu.pref_data
#define CPU_ADDRESS_MASK m68ki_cpu.address_mask
#define CPU_SR_MASK m68ki_cpu.sr_mask
#define CPU_INSTR_MODE m68ki_cpu.instr_mode
#define CPU_RUN_MODE m68ki_cpu.run_mode
#define CYC_INSTRUCTION m68ki_cpu.cyc_instruction
#define CYC_EXCEPTION m68ki_cpu.cyc_exception
#define CYC_BCC_NOTAKE_B m68ki_cpu.cyc_bcc_notake_b
#define CYC_BCC_NOTAKE_W m68ki_cpu.cyc_bcc_notake_w
#define CYC_DBCC_F_NOEXP m68ki_cpu.cyc_dbcc_f_noexp
#define CYC_DBCC_F_EXP m68ki_cpu.cyc_dbcc_f_exp
#define CYC_SCC_R_TRUE m68ki_cpu.cyc_scc_r_true
#define CYC_MOVEM_W m68ki_cpu.cyc_movem_w
#define CYC_MOVEM_L m68ki_cpu.cyc_movem_l
#define CYC_SHIFT m68ki_cpu.cyc_shift
#define CYC_RESET m68ki_cpu.cyc_reset
#define CALLBACK_INT_ACK m68ki_cpu.int_ack_callback
#define CALLBACK_BKPT_ACK m68ki_cpu.bkpt_ack_callback
#define CALLBACK_RESET_INSTR m68ki_cpu.reset_instr_callback
#define CALLBACK_PC_CHANGED m68ki_cpu.pc_changed_callback
#define CALLBACK_SET_FC m68ki_cpu.set_fc_callback
#define CALLBACK_INSTR_HOOK m68ki_cpu.instr_hook_callback
/* ----------------------------- Configuration ---------------------------- */
/* These defines are dependant on the configuration defines in m68kconf.h */
/* Disable certain comparisons if we're not using all CPU types */
#if M68K_EMULATE_020
#define CPU_TYPE_IS_020_PLUS(A) ((A) & CPU_TYPE_020)
#define CPU_TYPE_IS_020_LESS(A) 1
#else
#define CPU_TYPE_IS_020_PLUS(A) 0
#define CPU_TYPE_IS_020_LESS(A) 1
#endif
#if M68K_EMULATE_EC020
#define CPU_TYPE_IS_EC020_PLUS(A) ((A) & (CPU_TYPE_EC020 | CPU_TYPE_020))
#define CPU_TYPE_IS_EC020_LESS(A) ((A) & (CPU_TYPE_000 | CPU_TYPE_010 | CPU_TYPE_EC020))
#else
#define CPU_TYPE_IS_EC020_PLUS(A) CPU_TYPE_IS_020_PLUS(A)
#define CPU_TYPE_IS_EC020_LESS(A) CPU_TYPE_IS_020_LESS(A)
#endif
#if M68K_EMULATE_010
#define CPU_TYPE_IS_010(A) ((A) == CPU_TYPE_010)
#define CPU_TYPE_IS_010_PLUS(A) ((A) & (CPU_TYPE_010 | CPU_TYPE_EC020 | CPU_TYPE_020))
#define CPU_TYPE_IS_010_LESS(A) ((A) & (CPU_TYPE_000 | CPU_TYPE_010))
#else
#define CPU_TYPE_IS_010(A) 0
#define CPU_TYPE_IS_010_PLUS(A) CPU_TYPE_IS_EC020_PLUS(A)
#define CPU_TYPE_IS_010_LESS(A) CPU_TYPE_IS_EC020_LESS(A)
#endif
#if M68K_EMULATE_020 || M68K_EMULATE_EC020
#define CPU_TYPE_IS_020_VARIANT(A) ((A) & (CPU_TYPE_EC020 | CPU_TYPE_020))
#else
#define CPU_TYPE_IS_020_VARIANT(A) 0
#endif
#if M68K_EMULATE_020 || M68K_EMULATE_EC020 || M68K_EMULATE_010
#define CPU_TYPE_IS_000(A) ((A) == CPU_TYPE_000)
#else
#define CPU_TYPE_IS_000(A) 1
#endif
#if !M68K_SEPARATE_READS
#define m68k_read_immediate_16(A) m68ki_read_program_16(A)
#define m68k_read_immediate_32(A) m68ki_read_program_32(A)
#define m68k_read_pcrelative_8(A) m68ki_read_program_8(A)
#define m68k_read_pcrelative_16(A) m68ki_read_program_16(A)
#define m68k_read_pcrelative_32(A) m68ki_read_program_32(A)
#endif /* M68K_SEPARATE_READS */
/* Enable or disable callback functions */
#if M68K_EMULATE_INT_ACK
#if M68K_EMULATE_INT_ACK == OPT_SPECIFY_HANDLER
#define m68ki_int_ack(A) M68K_INT_ACK_CALLBACK(A)
#else
#define m68ki_int_ack(A) CALLBACK_INT_ACK(A)
#endif
#else
/* Default action is to used autovector mode, which is most common */
#define m68ki_int_ack(A) M68K_INT_ACK_AUTOVECTOR
#endif /* M68K_EMULATE_INT_ACK */
#if M68K_EMULATE_BKPT_ACK
#if M68K_EMULATE_BKPT_ACK == OPT_SPECIFY_HANDLER
#define m68ki_bkpt_ack(A) M68K_BKPT_ACK_CALLBACK(A)
#else
#define m68ki_bkpt_ack(A) CALLBACK_BKPT_ACK(A)
#endif
#else
#define m68ki_bkpt_ack(A)
#endif /* M68K_EMULATE_BKPT_ACK */
#if M68K_EMULATE_RESET
#if M68K_EMULATE_RESET == OPT_SPECIFY_HANDLER
#define m68ki_output_reset() M68K_RESET_CALLBACK()
#else
#define m68ki_output_reset() CALLBACK_RESET_INSTR()
#endif
#else
#define m68ki_output_reset()
#endif /* M68K_EMULATE_RESET */
#if M68K_INSTRUCTION_HOOK
#if M68K_INSTRUCTION_HOOK == OPT_SPECIFY_HANDLER
#define m68ki_instr_hook() M68K_INSTRUCTION_CALLBACK()
#else
#define m68ki_instr_hook() CALLBACK_INSTR_HOOK()
#endif
#else
#define m68ki_instr_hook()
#endif /* M68K_INSTRUCTION_HOOK */
#if M68K_MONITOR_PC
#if M68K_MONITOR_PC == OPT_SPECIFY_HANDLER
#define m68ki_pc_changed(A) M68K_SET_PC_CALLBACK(ADDRESS_68K(A))
#else
#define m68ki_pc_changed(A) CALLBACK_PC_CHANGED(ADDRESS_68K(A))
#endif
#else
#define m68ki_pc_changed(A)
#endif /* M68K_MONITOR_PC */
/* Enable or disable function code emulation */
#if M68K_EMULATE_FC
#if M68K_EMULATE_FC == OPT_SPECIFY_HANDLER
#define m68ki_set_fc(A) M68K_SET_FC_CALLBACK(A)
#else
#define m68ki_set_fc(A) CALLBACK_SET_FC(A)
#endif
#define m68ki_use_data_space() m68ki_address_space = FUNCTION_CODE_USER_DATA
#define m68ki_use_program_space() m68ki_address_space = FUNCTION_CODE_USER_PROGRAM
#define m68ki_get_address_space() m68ki_address_space
#else
#define m68ki_set_fc(A)
#define m68ki_use_data_space()
#define m68ki_use_program_space()
#define m68ki_get_address_space() FUNCTION_CODE_USER_DATA
#endif /* M68K_EMULATE_FC */
/* Enable or disable trace emulation */
#if M68K_EMULATE_TRACE
/* Initiates trace checking before each instruction (t1) */
#define m68ki_trace_t1() m68ki_tracing = FLAG_T1
/* adds t0 to trace checking if we encounter change of flow */
#define m68ki_trace_t0() m68ki_tracing |= FLAG_T0
/* Clear all tracing */
#define m68ki_clear_trace() m68ki_tracing = 0
/* Cause a trace exception if we are tracing */
#define m68ki_exception_if_trace() if(m68ki_tracing) m68ki_exception_trace()
#else
#define m68ki_trace_t1()
#define m68ki_trace_t0()
#define m68ki_clear_trace()
#define m68ki_exception_if_trace()
#endif /* M68K_EMULATE_TRACE */
/* Address error */
#if M68K_EMULATE_ADDRESS_ERROR
#include <setjmp.h>
extern jmp_buf m68ki_aerr_trap;
#define m68ki_set_address_error_trap() \
if(setjmp(m68ki_aerr_trap) != 0) \
{ \
m68ki_exception_address_error(); \
if(CPU_STOPPED) \
{ \
SET_CYCLES(0); \
CPU_INT_CYCLES = 0; \
return m68ki_initial_cycles; \
} \
}
#define m68ki_check_address_error(ADDR, WRITE_MODE, FC) \
if((ADDR)&1) \
{ \
m68ki_aerr_address = ADDR; \
m68ki_aerr_write_mode = WRITE_MODE; \
m68ki_aerr_fc = FC; \
longjmp(m68ki_aerr_trap, 1); \
}
#else
#define m68ki_set_address_error_trap()
#define m68ki_check_address_error(ADDR, WRITE_MODE, FC)
#endif /* M68K_ADDRESS_ERROR */
/* Logging */
#if M68K_LOG_ENABLE
#include <stdio.h>
extern FILE* M68K_LOG_FILEHANDLE
extern char* m68ki_cpu_names[];
#define M68K_DO_LOG(A) if(M68K_LOG_FILEHANDLE) fprintf A
#if M68K_LOG_1010_1111
#define M68K_DO_LOG_EMU(A) if(M68K_LOG_FILEHANDLE) fprintf A
#else
#define M68K_DO_LOG_EMU(A)
#endif
#else
#define M68K_DO_LOG(A)
#define M68K_DO_LOG_EMU(A)
#endif
/* -------------------------- EA / Operand Access ------------------------- */
/*
* The general instruction format follows this pattern:
* .... XXX. .... .YYY
* where XXX is register X and YYY is register Y
*/
/* Data Register Isolation */
#define DX (REG_D[(REG_IR >> 9) & 7])
#define DY (REG_D[REG_IR & 7])
/* Address Register Isolation */
#define AX (REG_A[(REG_IR >> 9) & 7])
#define AY (REG_A[REG_IR & 7])
/* Effective Address Calculations */
#define EA_AY_AI_8() AY /* address register indirect */
#define EA_AY_AI_16() EA_AY_AI_8()
#define EA_AY_AI_32() EA_AY_AI_8()
#define EA_AY_PI_8() (AY++) /* postincrement (size = byte) */
#define EA_AY_PI_16() ((AY+=2)-2) /* postincrement (size = word) */
#define EA_AY_PI_32() ((AY+=4)-4) /* postincrement (size = long) */
#define EA_AY_PD_8() (--AY) /* predecrement (size = byte) */
#define EA_AY_PD_16() (AY-=2) /* predecrement (size = word) */
#define EA_AY_PD_32() (AY-=4) /* predecrement (size = long) */
#define EA_AY_DI_8() (AY+MAKE_INT_16(m68ki_read_imm_16())) /* displacement */
#define EA_AY_DI_16() EA_AY_DI_8()
#define EA_AY_DI_32() EA_AY_DI_8()
#define EA_AY_IX_8() m68ki_get_ea_ix(AY) /* indirect + index */
#define EA_AY_IX_16() EA_AY_IX_8()
#define EA_AY_IX_32() EA_AY_IX_8()
#define EA_AX_AI_8() AX
#define EA_AX_AI_16() EA_AX_AI_8()
#define EA_AX_AI_32() EA_AX_AI_8()
#define EA_AX_PI_8() (AX++)
#define EA_AX_PI_16() ((AX+=2)-2)
#define EA_AX_PI_32() ((AX+=4)-4)
#define EA_AX_PD_8() (--AX)
#define EA_AX_PD_16() (AX-=2)
#define EA_AX_PD_32() (AX-=4)
#define EA_AX_DI_8() (AX+MAKE_INT_16(m68ki_read_imm_16()))
#define EA_AX_DI_16() EA_AX_DI_8()
#define EA_AX_DI_32() EA_AX_DI_8()
#define EA_AX_IX_8() m68ki_get_ea_ix(AX)
#define EA_AX_IX_16() EA_AX_IX_8()
#define EA_AX_IX_32() EA_AX_IX_8()
#define EA_A7_PI_8() ((REG_A[7]+=2)-2)
#define EA_A7_PD_8() (REG_A[7]-=2)
#define EA_AW_8() MAKE_INT_16(m68ki_read_imm_16()) /* absolute word */
#define EA_AW_16() EA_AW_8()
#define EA_AW_32() EA_AW_8()
#define EA_AL_8() m68ki_read_imm_32() /* absolute long */
#define EA_AL_16() EA_AL_8()
#define EA_AL_32() EA_AL_8()
#define EA_PCDI_8() m68ki_get_ea_pcdi() /* pc indirect + displacement */
#define EA_PCDI_16() EA_PCDI_8()
#define EA_PCDI_32() EA_PCDI_8()
#define EA_PCIX_8() m68ki_get_ea_pcix() /* pc indirect + index */
#define EA_PCIX_16() EA_PCIX_8()
#define EA_PCIX_32() EA_PCIX_8()
#define OPER_I_8() m68ki_read_imm_8()
#define OPER_I_16() m68ki_read_imm_16()
#define OPER_I_32() m68ki_read_imm_32()
/* --------------------------- Status Register ---------------------------- */
/* Flag Calculation Macros */
#define CFLAG_8(A) (A)
#define CFLAG_16(A) ((A)>>8)
#if M68K_INT_GT_32_BIT
#define CFLAG_ADD_32(S, D, R) ((R)>>24)
#define CFLAG_SUB_32(S, D, R) ((R)>>24)
#else
#define CFLAG_ADD_32(S, D, R) (((S & D) | (~R & (S | D)))>>23)
#define CFLAG_SUB_32(S, D, R) (((S & R) | (~D & (S | R)))>>23)
#endif /* M68K_INT_GT_32_BIT */
#define VFLAG_ADD_8(S, D, R) ((S^R) & (D^R))
#define VFLAG_ADD_16(S, D, R) (((S^R) & (D^R))>>8)
#define VFLAG_ADD_32(S, D, R) (((S^R) & (D^R))>>24)
#define VFLAG_SUB_8(S, D, R) ((S^D) & (R^D))
#define VFLAG_SUB_16(S, D, R) (((S^D) & (R^D))>>8)
#define VFLAG_SUB_32(S, D, R) (((S^D) & (R^D))>>24)
#define NFLAG_8(A) (A)
#define NFLAG_16(A) ((A)>>8)
#define NFLAG_32(A) ((A)>>24)
#define NFLAG_64(A) ((A)>>56)
#define ZFLAG_8(A) MASK_OUT_ABOVE_8(A)
#define ZFLAG_16(A) MASK_OUT_ABOVE_16(A)
#define ZFLAG_32(A) MASK_OUT_ABOVE_32(A)
/* Flag values */
#define NFLAG_SET 0x80
#define NFLAG_CLEAR 0
#define CFLAG_SET 0x100
#define CFLAG_CLEAR 0
#define XFLAG_SET 0x100
#define XFLAG_CLEAR 0
#define VFLAG_SET 0x80
#define VFLAG_CLEAR 0
#define ZFLAG_SET 0
#define ZFLAG_CLEAR 0xffffffff
#define SFLAG_SET 4
#define SFLAG_CLEAR 0
#define MFLAG_SET 2
#define MFLAG_CLEAR 0
/* Turn flag values into 1 or 0 */
#define XFLAG_AS_1() ((FLAG_X>>8)&1)
#define NFLAG_AS_1() ((FLAG_N>>7)&1)
#define VFLAG_AS_1() ((FLAG_V>>7)&1)
#define ZFLAG_AS_1() (!FLAG_Z)
#define CFLAG_AS_1() ((FLAG_C>>8)&1)
/* Conditions */
#define COND_CS() (FLAG_C&0x100)
#define COND_CC() (!COND_CS())
#define COND_VS() (FLAG_V&0x80)
#define COND_VC() (!COND_VS())
#define COND_NE() FLAG_Z
#define COND_EQ() (!COND_NE())
#define COND_MI() (FLAG_N&0x80)
#define COND_PL() (!COND_MI())
#define COND_LT() ((FLAG_N^FLAG_V)&0x80)
#define COND_GE() (!COND_LT())
#define COND_HI() (COND_CC() && COND_NE())
#define COND_LS() (COND_CS() || COND_EQ())
#define COND_GT() (COND_GE() && COND_NE())
#define COND_LE() (COND_LT() || COND_EQ())
/* Reversed conditions */
#define COND_NOT_CS() COND_CC()
#define COND_NOT_CC() COND_CS()
#define COND_NOT_VS() COND_VC()
#define COND_NOT_VC() COND_VS()
#define COND_NOT_NE() COND_EQ()
#define COND_NOT_EQ() COND_NE()
#define COND_NOT_MI() COND_PL()
#define COND_NOT_PL() COND_MI()
#define COND_NOT_LT() COND_GE()
#define COND_NOT_GE() COND_LT()
#define COND_NOT_HI() COND_LS()
#define COND_NOT_LS() COND_HI()
#define COND_NOT_GT() COND_LE()
#define COND_NOT_LE() COND_GT()
/* Not real conditions, but here for convenience */
#define COND_XS() (FLAG_X&0x100)
#define COND_XC() (!COND_XS)
/* Get the condition code register */
#define m68ki_get_ccr() ((COND_XS() >> 4) | \
(COND_MI() >> 4) | \
(COND_EQ() << 2) | \
(COND_VS() >> 6) | \
(COND_CS() >> 8))
/* Get the status register */
#define m68ki_get_sr() ( FLAG_T1 | \
FLAG_T0 | \
(FLAG_S << 11) | \
(FLAG_M << 11) | \
FLAG_INT_MASK | \
m68ki_get_ccr())
/* ---------------------------- Cycle Counting ---------------------------- */
#define ADD_CYCLES(A) m68ki_remaining_cycles += (A)
#define USE_CYCLES(A) m68ki_remaining_cycles -= (A)
#define SET_CYCLES(A) m68ki_remaining_cycles = A
#define GET_CYCLES() m68ki_remaining_cycles
#define USE_ALL_CYCLES() m68ki_remaining_cycles %= CYC_INSTRUCTION[REG_IR]
/* ----------------------------- Read / Write ----------------------------- */
/* Read from the current address space */
#define m68ki_read_8(A) m68ki_read_8_fc (A, FLAG_S | m68ki_get_address_space())
#define m68ki_read_16(A) m68ki_read_16_fc(A, FLAG_S | m68ki_get_address_space())
#define m68ki_read_32(A) m68ki_read_32_fc(A, FLAG_S | m68ki_get_address_space())
/* Write to the current data space */
#define m68ki_write_8(A, V) m68ki_write_8_fc (A, FLAG_S | FUNCTION_CODE_USER_DATA, V)
#define m68ki_write_16(A, V) m68ki_write_16_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA, V)
#define m68ki_write_32(A, V) m68ki_write_32_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA, V)
#if M68K_SIMULATE_PD_WRITES
#define m68ki_write_32_pd(A, V) m68ki_write_32_pd_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA, V)
#else
#define m68ki_write_32_pd(A, V) m68ki_write_32_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA, V)
#endif
/* map read immediate 8 to read immediate 16 */
#define m68ki_read_imm_8() MASK_OUT_ABOVE_8(m68ki_read_imm_16())
/* Map PC-relative reads */
#define m68ki_read_pcrel_8(A) m68k_read_pcrelative_8(A)
#define m68ki_read_pcrel_16(A) m68k_read_pcrelative_16(A)
#define m68ki_read_pcrel_32(A) m68k_read_pcrelative_32(A)
/* Read from the program space */
#define m68ki_read_program_8(A) m68ki_read_8_fc(A, FLAG_S | FUNCTION_CODE_USER_PROGRAM)
#define m68ki_read_program_16(A) m68ki_read_16_fc(A, FLAG_S | FUNCTION_CODE_USER_PROGRAM)
#define m68ki_read_program_32(A) m68ki_read_32_fc(A, FLAG_S | FUNCTION_CODE_USER_PROGRAM)
/* Read from the data space */
#define m68ki_read_data_8(A) m68ki_read_8_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA)
#define m68ki_read_data_16(A) m68ki_read_16_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA)
#define m68ki_read_data_32(A) m68ki_read_32_fc(A, FLAG_S | FUNCTION_CODE_USER_DATA)
/* ======================================================================== */
/* =============================== PROTOTYPES ============================= */
/* ======================================================================== */
typedef struct
{
uint cpu_type; /* CPU Type: 68000, 68010, 68EC020, or 68020 */
uint dar[16]; /* Data and Address Registers */
uint ppc; /* Previous program counter */
uint pc; /* Program Counter */
uint sp[7]; /* User, Interrupt, and Master Stack Pointers */
uint vbr; /* Vector Base Register (m68010+) */
uint sfc; /* Source Function Code Register (m68010+) */
uint dfc; /* Destination Function Code Register (m68010+) */
uint cacr; /* Cache Control Register (m68020, unemulated) */
uint caar; /* Cache Address Register (m68020, unemulated) */
uint ir; /* Instruction Register */
uint t1_flag; /* Trace 1 */
uint t0_flag; /* Trace 0 */
uint s_flag; /* Supervisor */
uint m_flag; /* Master/Interrupt state */
uint x_flag; /* Extend */
uint n_flag; /* Negative */
uint not_z_flag; /* Zero, inverted for speedups */
uint v_flag; /* Overflow */
uint c_flag; /* Carry */
uint int_mask; /* I0-I2 */
uint int_level; /* State of interrupt pins IPL0-IPL2 -- ASG: changed from ints_pending */
uint int_cycles; /* ASG: extra cycles from generated interrupts */
uint stopped; /* Stopped state */
uint pref_addr; /* Last prefetch address */
uint pref_data; /* Data in the prefetch queue */
uint address_mask; /* Available address pins */
uint sr_mask; /* Implemented status register bits */
uint instr_mode; /* Stores whether we are in instruction mode or group 0/1 exception mode */
uint run_mode; /* Stores whether we are processing a reset, bus error, address error, or something else */
/* Clocks required for instructions / exceptions */
uint cyc_bcc_notake_b;
uint cyc_bcc_notake_w;
uint cyc_dbcc_f_noexp;
uint cyc_dbcc_f_exp;
uint cyc_scc_r_true;
uint cyc_movem_w;
uint cyc_movem_l;
uint cyc_shift;
uint cyc_reset;
uint8* cyc_instruction;
uint8* cyc_exception;
/* Callbacks to host */
int (*int_ack_callback)(int int_line); /* Interrupt Acknowledge */
void (*bkpt_ack_callback)(unsigned int data); /* Breakpoint Acknowledge */
void (*reset_instr_callback)(void); /* Called when a RESET instruction is encountered */
void (*pc_changed_callback)(unsigned int new_pc); /* Called when the PC changes by a large amount */
void (*set_fc_callback)(unsigned int new_fc); /* Called when the CPU function code changes */
void (*instr_hook_callback)(void); /* Called every instruction cycle prior to execution */
} m68ki_cpu_core;
extern m68ki_cpu_core m68ki_cpu;
extern sint m68ki_remaining_cycles;
extern uint m68ki_tracing;
extern uint8 m68ki_shift_8_table[];
extern uint16 m68ki_shift_16_table[];
extern uint m68ki_shift_32_table[];
extern uint8 m68ki_exception_cycle_table[][256];
extern uint m68ki_address_space;
extern uint8 m68ki_ea_idx_cycle_table[];
extern uint m68ki_aerr_address;
extern uint m68ki_aerr_write_mode;
extern uint m68ki_aerr_fc;
/* Read data immediately after the program counter */
INLINE uint m68ki_read_imm_16(void);
INLINE uint m68ki_read_imm_32(void);
/* Read data with specific function code */
INLINE uint m68ki_read_8_fc (uint address, uint fc);
INLINE uint m68ki_read_16_fc (uint address, uint fc);
INLINE uint m68ki_read_32_fc (uint address, uint fc);
/* Write data with specific function code */
INLINE void m68ki_write_8_fc (uint address, uint fc, uint value);
INLINE void m68ki_write_16_fc(uint address, uint fc, uint value);
INLINE void m68ki_write_32_fc(uint address, uint fc, uint value);
#if M68K_SIMULATE_PD_WRITES
INLINE void m68ki_write_32_pd_fc(uint address, uint fc, uint value);
#endif /* M68K_SIMULATE_PD_WRITES */
/* Indexed and PC-relative ea fetching */
INLINE uint m68ki_get_ea_pcdi(void);
INLINE uint m68ki_get_ea_pcix(void);
INLINE uint m68ki_get_ea_ix(uint An);
/* Operand fetching */
INLINE uint OPER_AY_AI_8(void);
INLINE uint OPER_AY_AI_16(void);
INLINE uint OPER_AY_AI_32(void);
INLINE uint OPER_AY_PI_8(void);
INLINE uint OPER_AY_PI_16(void);
INLINE uint OPER_AY_PI_32(void);
INLINE uint OPER_AY_PD_8(void);
INLINE uint OPER_AY_PD_16(void);
INLINE uint OPER_AY_PD_32(void);
INLINE uint OPER_AY_DI_8(void);
INLINE uint OPER_AY_DI_16(void);
INLINE uint OPER_AY_DI_32(void);
INLINE uint OPER_AY_IX_8(void);
INLINE uint OPER_AY_IX_16(void);
INLINE uint OPER_AY_IX_32(void);
INLINE uint OPER_AX_AI_8(void);
INLINE uint OPER_AX_AI_16(void);
INLINE uint OPER_AX_AI_32(void);
INLINE uint OPER_AX_PI_8(void);
INLINE uint OPER_AX_PI_16(void);
INLINE uint OPER_AX_PI_32(void);
INLINE uint OPER_AX_PD_8(void);
INLINE uint OPER_AX_PD_16(void);
INLINE uint OPER_AX_PD_32(void);
INLINE uint OPER_AX_DI_8(void);
INLINE uint OPER_AX_DI_16(void);
INLINE uint OPER_AX_DI_32(void);
INLINE uint OPER_AX_IX_8(void);
INLINE uint OPER_AX_IX_16(void);
INLINE uint OPER_AX_IX_32(void);
INLINE uint OPER_A7_PI_8(void);
INLINE uint OPER_A7_PD_8(void);
INLINE uint OPER_AW_8(void);
INLINE uint OPER_AW_16(void);
INLINE uint OPER_AW_32(void);
INLINE uint OPER_AL_8(void);
INLINE uint OPER_AL_16(void);
INLINE uint OPER_AL_32(void);
INLINE uint OPER_PCDI_8(void);
INLINE uint OPER_PCDI_16(void);
INLINE uint OPER_PCDI_32(void);
INLINE uint OPER_PCIX_8(void);
INLINE uint OPER_PCIX_16(void);
INLINE uint OPER_PCIX_32(void);
/* Stack operations */
INLINE void m68ki_push_16(uint value);
INLINE void m68ki_push_32(uint value);
INLINE uint m68ki_pull_16(void);
INLINE uint m68ki_pull_32(void);
/* Program flow operations */
INLINE void m68ki_jump(uint new_pc);
INLINE void m68ki_jump_vector(uint vector);
INLINE void m68ki_branch_8(uint offset);
INLINE void m68ki_branch_16(uint offset);
INLINE void m68ki_branch_32(uint offset);
/* Status register operations. */
INLINE void m68ki_set_s_flag(uint value); /* Only bit 2 of value should be set (i.e. 4 or 0) */
INLINE void m68ki_set_sm_flag(uint value); /* only bits 1 and 2 of value should be set */
INLINE void m68ki_set_ccr(uint value); /* set the condition code register */
INLINE void m68ki_set_sr(uint value); /* set the status register */
INLINE void m68ki_set_sr_noint(uint value); /* set the status register */
/* Exception processing */
INLINE uint m68ki_init_exception(void); /* Initial exception processing */
INLINE void m68ki_stack_frame_3word(uint pc, uint sr); /* Stack various frame types */
INLINE void m68ki_stack_frame_buserr(uint sr);
INLINE void m68ki_stack_frame_0000(uint pc, uint sr, uint vector);
INLINE void m68ki_stack_frame_0001(uint pc, uint sr, uint vector);
INLINE void m68ki_stack_frame_0010(uint sr, uint vector);
INLINE void m68ki_stack_frame_1000(uint pc, uint sr, uint vector);
INLINE void m68ki_stack_frame_1010(uint sr, uint vector, uint pc);
INLINE void m68ki_stack_frame_1011(uint sr, uint vector, uint pc);
INLINE void m68ki_exception_trap(uint vector);
INLINE void m68ki_exception_trapN(uint vector);
INLINE void m68ki_exception_trace(void);
INLINE void m68ki_exception_privilege_violation(void);
INLINE void m68ki_exception_1010(void);
INLINE void m68ki_exception_1111(void);
INLINE void m68ki_exception_illegal(void);
INLINE void m68ki_exception_format_error(void);
INLINE void m68ki_exception_address_error(void);
INLINE void m68ki_exception_interrupt(uint int_level);
INLINE void m68ki_check_interrupts(void); /* ASG: check for interrupts */
/* quick disassembly (used for logging) */
char* m68ki_disassemble_quick(unsigned int pc, unsigned int cpu_type);
/* ======================================================================== */
/* =========================== UTILITY FUNCTIONS ========================== */
/* ======================================================================== */
/* ---------------------------- Read Immediate ---------------------------- */
/* Handles all immediate reads, does address error check, function code setting,
* and prefetching if they are enabled in m68kconf.h
*/
INLINE uint m68ki_read_imm_16(void)
{
m68ki_set_fc(FLAG_S | FUNCTION_CODE_USER_PROGRAM); /* auto-disable (see m68kcpu.h) */
m68ki_check_address_error(REG_PC, MODE_READ, FLAG_S | FUNCTION_CODE_USER_PROGRAM); /* auto-disable (see m68kcpu.h) */
#if M68K_EMULATE_PREFETCH
if(MASK_OUT_BELOW_2(REG_PC) != CPU_PREF_ADDR)