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/* Unit tests and test harness for 680 project.
*
* Copyright 2011, Astrid Smith
* GPL
*/
#define TEST 1
#include <default.h>
/* These values are hard-coded into the assembly code in do_instr
* below. TREAD LIGHTLY.
*/
enum z80regs {
/* normal registers */
REG_A = 0,
REG_F = 1,
REG_B = 2,
REG_C = 3,
REG_D = 4,
REG_E = 5,
REG_H = 6, REG_L = 7,
REG_IX_H = 8, REG_IX_L = 9,
REG_IY_H = 10, REG_IY_L = 11,
/* shadow registers */
REG_A_ = 12,
REG_F_ = 13,
REG_B_ = 14,
REG_C_ = 15,
REG_D_ = 16,
REG_E_ = 17,
REG_H_ = 18, REG_L_ = 19,
REG_IX_H_ = 20, REG_IX_L_ = 21,
REG_IY_H_ = 22, REG_IY_L_ = 23,
REG_SP_H = 24, REG_SP_L = 25,
REG_PC_H = 26, REG_PC_L = 27,
REG_number_of_registers = 28
};
typedef struct {
// registers
char regs[28];
// storage space for instruction, immediate values, etc
char program[8];
// storage space for emulated stack
char stack[8];
// emulated addresses $fff8 - $0007
char heap[8];
} z80_state_t;
void _main(void) {
z80_state_t foo;
}
/* function to execute an instruction, using the state indicated by
* z80_state_t 'proc'.
*/
void do_instr(z80_state_t *proc_begin, z80_state_t *proc_end)
{
/* For offsets, use the values in enum z80regs above.
*/
asm( "
movem.l d3-d7/a3-a6,-(a7)
movem.l d0-d2/a0-a3,-(a7)
move.l %[regs_out],-(a7)
||| register setup
lea emu_plain_op,a5
move.l %[regs_in],a0
movea.l %[epc],a6
movea.l %[esp],a4
move.b 13(a0),d3 | f_
rol.w #8,d3
move.b 12(a0),d3 | a_
rol.w #8,d3
move.b 1(a0),d3 | f
rol.w #8,d3
move.b 0(a0),d3 | a
move.b 14(a0),d4 | b_
rol.w #8,d4
move.b 15(a0),d4 | c_
rol.w #8,d4
move.b 2(a0),d4 | b
rol.w #8,d4
move.b 3(a0),d4 | c
move.b 16(a0),d5 | d_
rol.w #8,d5
move.b 17(a0),d5 | e_
rol.w #8,d5
move.b 4(a0),d5 | d
rol.w #8,d5
move.b 5(a0),d5 | e
move.b 18(a0),d6 | h_
rol.w #8,d6
move.b 19(a0),d6 | l_
rol.w #8,d6
move.b 6(a0),d6 | h
rol.w #8,d6
move.b 7(a0),d6 | l
||| call the routine
||| register teardown
move.l (a7)+,a0 | pop regs_out
movem.l d0-d2/a0-a3,-(a7) | pop other stuff, to give gcc room to play in
move.b d3,13(a0) | f_
rol.w #8,d3
move.b d3,12(a0) | a_
rol.w #8,d3
move.b d3,1(a0) | f
rol.w #8,d3
move.b d3,0(a0) | a
move.b d4,14(a0) | b_
rol.w #8,d4
move.b d4,15(a0) | c_
rol.w #8,d4
move.b d4,2(a0) | b
rol.w #8,d4
move.b d4,3(a0) | c
move.b d5,16(a0) | d_
rol.w #8,d5
move.b d5,17(a0) | e_
rol.w #8,d5
move.b d5,4(a0) | d
rol.w #8,d5
move.b d5,5(a0) | e
move.b d6,18(a0) | h_
rol.w #8,d6
move.b d6,19(a0) | l_
rol.w #8,d6
move.b d6,6(a0) | h
rol.w #8,d6
move.b d6,7(a0) | l
movem (a7)+,d3-d7/a1-a6
"
:
: [regs_in] "p" (proc_begin->regs),
[regs_out] "p" (proc_end->regs),
[epc] "p" (*proc_begin->program),
[esp] "p" (*proc_begin->stack)
: "memory", "a0"
);
}
|
