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authorMichael Pavone <pavone@retrodev.com>2016-08-01 09:48:10 -0700
committerMichael Pavone <pavone@retrodev.com>2016-08-01 09:48:10 -0700
commit846bdd563475770c698e1911fbb98ec99f980866 (patch)
tree9eec70cd611e5ec8fcaf6cb0c682b11f640ce6d5 /z80_to_x86.c
parent5b0d7f25f96901cc092184a14a3c3c69061d674b (diff)
Implement INI
Diffstat (limited to 'z80_to_x86.c')
-rw-r--r--z80_to_x86.c60
1 files changed, 58 insertions, 2 deletions
diff --git a/z80_to_x86.c b/z80_to_x86.c
index 204cb24..07dd5ec 100644
--- a/z80_to_x86.c
+++ b/z80_to_x86.c
@@ -2336,8 +2336,64 @@ void translate_z80inst(z80inst * inst, z80_context * context, uint16_t address,
}
z80_save_reg(inst, opts);
break;
- /*case Z80_INI:
- case Z80_INIR:
+ case Z80_INI:
+ cycles(&opts->gen, num_cycles + 1);//T States: 4, 5
+ //read from IO (C)
+ zreg_to_native(opts, Z80_BC, opts->gen.scratch1);
+ call(code, opts->read_io);//T states 3
+
+ //undocumented N flag behavior
+ //flag set on bit 7 of value written
+ bt_ir(code, 7, opts->gen.scratch1, SZ_B);
+ setcc_rdisp(code, CC_C, opts->gen.context_reg, zf_off(ZF_N));
+ //save value to be written for flag calculation, as the write func does not
+ //guarantee that it's preserved across the call
+ mov_rrdisp(code, opts->gen.scratch1, opts->gen.context_reg, offsetof(z80_context, scratch1), SZ_B);
+
+ //write to (HL)
+ zreg_to_native(opts, Z80_HL, opts->gen.scratch2);
+ call(code, opts->write_8);//T states 4
+ cycles(&opts->gen, 1);
+
+ //increment HL
+ if (opts->regs[Z80_HL] >= 0) {
+ add_ir(code, 1, opts->regs[Z80_HL], SZ_W);
+ } else {
+ add_irdisp(code, 1, opts->gen.context_reg, zr_off(Z80_HL), SZ_B);
+ }
+ mov_rdispr(code, opts->gen.context_reg, offsetof(z80_context, scratch1), opts->gen.scratch1, SZ_B);
+ if (opts->regs[Z80_C] >= 0) {
+ add_rr(code, opts->regs[Z80_C], opts->gen.scratch1, SZ_B);
+ } else {
+ add_rdispr(code, opts->gen.context_reg, zr_off(Z80_C), opts->gen.scratch1, SZ_B);
+ }
+ add_ir(code, 1, opts->gen.scratch1, SZ_B);
+ //undocumented C and H flag behavior
+ setcc_rdisp(code, CC_C, opts->gen.context_reg, zf_off(ZF_C));
+ setcc_rdisp(code, CC_C, opts->gen.context_reg, zf_off(ZF_H));
+ //decrement B
+ if (opts->regs[Z80_B] >= 0) {
+ sub_ir(code, 1, opts->regs[Z80_B], SZ_B);
+ mov_rrdisp(code, opts->regs[Z80_B], opts->gen.context_reg, zf_off(ZF_XY), SZ_B);
+ } else {
+ sub_irdisp(code, 1, opts->gen.context_reg, zr_off(Z80_B), SZ_B);
+ }
+ //undocumented Z and S flag behavior, set based on decrement of B
+ setcc_rdisp(code, CC_Z, opts->gen.context_reg, zf_off(ZF_Z));
+ setcc_rdisp(code, CC_S, opts->gen.context_reg, zf_off(ZF_S));
+ //crazy undocumented P/V flag behavior
+ and_ir(code, 7, opts->gen.scratch1, SZ_B);
+ if (opts->regs[Z80_B] >= 0) {
+ //deal with silly x86-64 restrictions on *H registers
+ ror_ir(code, 8, opts->regs[Z80_BC], SZ_W);
+ xor_rr(code, opts->regs[Z80_C], opts->gen.scratch1, SZ_B);
+ ror_ir(code, 8, opts->regs[Z80_BC], SZ_W);
+ } else {
+ xor_rdispr(code, opts->gen.context_reg, zr_off(Z80_B), opts->gen.scratch1, SZ_B);
+ }
+ setcc_rdisp(code, CC_P, opts->gen.context_reg, zf_off(ZF_PV));
+ break;
+ /*case Z80_INIR:
case Z80_IND:
case Z80_INDR:*/
case Z80_OUT: