Implement LD A, I/R; CPI/CPIR/CPD/CPDR

src/z80_flags.inc.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 2014-2016 Ben Kurtovic <ben.kurtovic@gmail.com>
+/* Copyright (C) 2014-2019 Ben Kurtovic <ben.kurtovic@gmail.com>
    Released under the terms of the MIT License. See LICENSE for details. */
 
 #define POS(x) (!((x) & 0x80))
@@ -211,6 +211,15 @@ static inline void set_flags_scf(Z80 *z80)
 }
 
 /*
+    Set the flags for a LD A, I/R instruction.
+*/
+static inline void set_flags_ld_a_ir(Z80 *z80)
+{
+    uint8_t val = z80->regs.a;
+    set_flags(z80, 0, 0, z80->regs.iff2, F3(val), 0, F5(val), ZERO(val), SIGN(val), 0xFE);
+}
+
+/*
     Set the flags for a LDI/LDIR/LDD/LDDR instruction.
 */
 static inline void set_flags_blockxfer(Z80 *z80, uint8_t val)
@@ -221,6 +230,19 @@ static inline void set_flags_blockxfer(Z80 *z80, uint8_t val)
 }
 
 /*
+    Set the flags for a CPI/CPIR/CPD/CPDR instruction.
+*/
+static inline void set_flags_blockcp(Z80 *z80, uint16_t rh)
+{
+    uint8_t lh = z80->regs.a;
+    bool pv = z80->regs.bc != 0;
+    bool h = HALF(lh, -, rh);
+    uint8_t res = lh - rh;
+    uint8_t resh = res - h;
+    set_flags(z80, 0, 1, pv, F3(resh), h, F5(resh), ZERO(res), SIGN(res), 0xFE);
+}
+
+/*
     Set the flags for an IN instruction.
 */
 static inline void set_flags_in(Z80 *z80, uint8_t val)

src/z80_ops.inc.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 2014-2016 Ben Kurtovic <ben.kurtovic@gmail.com>
+/* Copyright (C) 2014-2019 Ben Kurtovic <ben.kurtovic@gmail.com>
    Released under the terms of the MIT License. See LICENSE for details. */
 
 /*
@@ -193,16 +193,28 @@ static uint8_t z80_inst_ld_nn_a(Z80 *z80, uint8_t opcode)
 /*
     LD A, I (0xED57):
     Load I into A.
-    TODO
 */
-// static uint8_t z80_inst_ld_a_i(Z80 *z80, uint8_t opcode)
+static uint8_t z80_inst_ld_a_i(Z80 *z80, uint8_t opcode)
+{
+    (void) opcode;
+    z80->regs.a = z80->regs.i;
+    set_flags_ld_a_ir(z80);
+    z80->regs.pc++;
+    return 9;
+}
 
 /*
     LD A, R (0xED5F):
     Load R into A.
-    TODO
 */
-// static uint8_t z80_inst_ld_a_r(Z80 *z80, uint8_t opcode)
+static uint8_t z80_inst_ld_a_r(Z80 *z80, uint8_t opcode)
+{
+    (void) opcode;
+    z80->regs.a = z80->regs.r;
+    set_flags_ld_a_ir(z80);
+    z80->regs.pc++;
+    return 9;
+}
 
 /*
     LD I, A (0xED47):
@@ -536,13 +548,65 @@ static uint8_t z80_inst_lddr(Z80 *z80, uint8_t opcode)
     return 21;
 }
 
-// TODO: CPI
+/*
+    CPI (0xEDA1):
+    CP (HL); INC HL; DEC BL
+*/
+static uint8_t z80_inst_cpi(Z80 *z80, uint8_t opcode)
+{
+    (void) opcode;
+    uint8_t value = mmu_read_byte(z80->mmu, z80->regs.hl);
+
+    z80->regs.hl++;
+    z80->regs.bc--;
+
+    set_flags_blockcp(z80, value);
+    z80->regs.pc++;
+    return 16;
+}
+
+/*
+    CPIR (0xEDB1):
+    CPI; JR PV; -2
+*/
+static uint8_t z80_inst_cpir(Z80 *z80, uint8_t opcode)
+{
+    z80_inst_cpi(z80, opcode);
+    if (z80->regs.bc == 0)
+        return 16;
+    z80->regs.pc -= 2;
+    return 21;
+}
+
+/*
+    CPD (0xEDA9):
+    CP (HL); DEC HL; DEC BL
+*/
+static uint8_t z80_inst_cpd(Z80 *z80, uint8_t opcode)
+{
+    (void) opcode;
+    uint8_t value = mmu_read_byte(z80->mmu, z80->regs.hl);
 
-// TODO: CPIR
+    z80->regs.hl--;
+    z80->regs.bc--;
 
-// TODO: CPD
+    set_flags_blockcp(z80, value);
+    z80->regs.pc++;
+    return 16;
+}
 
-// TODO: CPDR
+/*
+    CPDR (0xEDB9):
+    CPD; JR PV; -2
+*/
+static uint8_t z80_inst_cpdr(Z80 *z80, uint8_t opcode)
+{
+    z80_inst_cpd(z80, opcode);
+    if (z80->regs.bc == 0)
+        return 16;
+    z80->regs.pc -= 2;
+    return 21;
+}
 
 /*
     ADD A, r (0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x87):

src/z80_tables.inc.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 2014-2016 Ben Kurtovic <ben.kurtovic@gmail.com>
+/* Copyright (C) 2014-2019 Ben Kurtovic <ben.kurtovic@gmail.com>
    Released under the terms of the MIT License. See LICENSE for details. */
 
 static DispatchTable instruction_table = {
@@ -348,7 +348,7 @@ static DispatchTable instruction_table_extended = {
     [0x54] = z80_inst_neg,
     [0x55] = z80_inst_retn,
     [0x56] = z80_inst_im,
-    [0x57] = z80_inst_unimplemented,  // TODO
+    [0x57] = z80_inst_ld_a_i,
     [0x58] = z80_inst_in_r_c,
     [0x59] = z80_inst_out_c_r,
     [0x5A] = z80_inst_adc_hl_ss,
@@ -356,7 +356,7 @@ static DispatchTable instruction_table_extended = {
     [0x5C] = z80_inst_neg,
     [0x5D] = z80_inst_retn,
     [0x5E] = z80_inst_im,
-    [0x5F] = z80_inst_unimplemented,  // TODO
+    [0x5F] = z80_inst_ld_a_r,
     [0x60] = z80_inst_in_r_c,
     [0x61] = z80_inst_out_c_r,
     [0x62] = z80_inst_sbc_hl_ss,
@@ -422,7 +422,7 @@ static DispatchTable instruction_table_extended = {
     [0x9E] = z80_inst_nop2,
     [0x9F] = z80_inst_nop2,
     [0xA0] = z80_inst_ldi,
-    [0xA1] = z80_inst_unimplemented,  // TODO
+    [0xA1] = z80_inst_cpi,
     [0xA2] = z80_inst_ini,
     [0xA3] = z80_inst_outi,
     [0xA4] = z80_inst_nop2,
@@ -430,7 +430,7 @@ static DispatchTable instruction_table_extended = {
     [0xA6] = z80_inst_nop2,
     [0xA7] = z80_inst_nop2,
     [0xA8] = z80_inst_ldd,
-    [0xA9] = z80_inst_unimplemented,  // TODO
+    [0xA9] = z80_inst_cpd,
     [0xAA] = z80_inst_ind,
     [0xAB] = z80_inst_outd,
     [0xAC] = z80_inst_nop2,
@@ -438,7 +438,7 @@ static DispatchTable instruction_table_extended = {
     [0xAE] = z80_inst_nop2,
     [0xAF] = z80_inst_nop2,
     [0xB0] = z80_inst_ldir,
-    [0xB1] = z80_inst_unimplemented,  // TODO
+    [0xB1] = z80_inst_cpir,
     [0xB2] = z80_inst_inir,
     [0xB3] = z80_inst_otir,
     [0xB4] = z80_inst_nop2,
@@ -446,7 +446,7 @@ static DispatchTable instruction_table_extended = {
     [0xB6] = z80_inst_nop2,
     [0xB7] = z80_inst_nop2,
     [0xB8] = z80_inst_lddr,
-    [0xB9] = z80_inst_unimplemented,  // TODO
+    [0xB9] = z80_inst_cpdr,
     [0xBA] = z80_inst_indr,
     [0xBB] = z80_inst_otdr,
     [0xBC] = z80_inst_nop2,