add, adc, sub, sbc, inc, dec

Author: Prof9

Archs/GB/CGameboyInstruction.cpp

@@ -66,6 +66,38 @@ bool CGameboyInstruction::Validate(const ValidateState& state)
 			Vars.WriteImmediate16 = true;
 		}
 
+		// add <-> sub
+		if ((Opcode.flags & (GB_ADD_IMMEDIATE | GB_SUB_IMMEDIATE)) && Vars.Immediate < 0)
+		{
+			// Change opcode
+			Vars.Encoding ^= 0x10;
+			Vars.Immediate = -Vars.Immediate;
+		}
+		if (Opcode.flags & GB_NEGATE_IMM)
+		{
+			Vars.Immediate = -Vars.Immediate;
+		}
+		// add a,1 -> inc a
+		if ((Opcode.flags & GB_ADD_IMMEDIATE) && Vars.LeftParam.num == GB_REG8_A && Vars.Immediate == 1)
+		{
+			// Change opcode
+			Vars.Encoding = 0x3C;
+			Vars.Length = 1;
+			Vars.LeftParam.num = 0;
+			Vars.WriteImmediate8 = false;
+			Vars.WriteImmediate16 = false;
+		}
+		// sub a,1 -> dec a
+		if ((Opcode.flags & GB_SUB_IMMEDIATE) && Vars.LeftParam.num == GB_REG8_A && Vars.Immediate == 1)
+		{
+			// Change opcode
+			Vars.Encoding = 0x3D;
+			Vars.Length = 1;
+			Vars.LeftParam.num = 0;
+			Vars.WriteImmediate8 = false;
+			Vars.WriteImmediate16 = false;
+		}
+
 		// Special loads in range 0xFF00 - 0xFFFF
 		if (Vars.RightParam.num == GB_REG8_A && Vars.Immediate >= 0xFF00)
 		{

Archs/GB/GameboyOpcodes.cpp

@@ -28,16 +28,25 @@ const tGameboyOpcode GameboyOpcodes[] = {
 	{ L"ldd",	1,	0x3A,	GB_PARAM_A,				GB_PARAM_MEMHL,			-1,		-1,		0 },
 	{ L"push",	1,	0xC5,	GB_PARAM_REG16_AF,		GB_PARAM_NONE,			4,		-1,		0 },
 	{ L"pop",	1,	0xC1,	GB_PARAM_REG16_AF,		GB_PARAM_NONE,			4,		-1,		0 },
-//	{ L"add",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
-//	{ L"adc",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
-//	{ L"sub",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
-//	{ L"sbc",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
+	{ L"add",	1,	0x09,	GB_PARAM_HL,			GB_PARAM_REG16_SP,		-1,		4,		0 },
+	{ L"add",	1,	0x80,	GB_PARAM_A,				GB_PARAM_REG8_MEMHL,	-1,		0,		0 },
+	{ L"add",	2,	0xC6,	GB_PARAM_A,				GB_PARAM_IMMEDIATE,		-1,		-1,		GB_IMMEDIATE_U8 | GB_ADD_IMMEDIATE },
+	{ L"add",	2,	0xE8,	GB_PARAM_SP,			GB_PARAM_IMMEDIATE,		-1,		-1,		GB_IMMEDIATE_S8 },
+	{ L"adc",	1,	0x88,	GB_PARAM_A,				GB_PARAM_REG8_MEMHL,	-1,		0,		0 },
+	{ L"adc",	2,	0xCE,	GB_PARAM_A,				GB_PARAM_IMMEDIATE,		-1,		-1,		GB_IMMEDIATE_U8 | GB_ADD_IMMEDIATE },
+	{ L"sub",	1,	0x90,	GB_PARAM_A,				GB_PARAM_REG8_MEMHL,	-1,		0,		0 },
+	{ L"sub",	2,	0xD6,	GB_PARAM_A,				GB_PARAM_IMMEDIATE,		-1,		-1,		GB_IMMEDIATE_U8 | GB_SUB_IMMEDIATE },
+	{ L"sub",	2,	0xE8,	GB_PARAM_SP,			GB_PARAM_IMMEDIATE,		-1,		-1,		GB_IMMEDIATE_S8 | GB_NEGATE_IMM },
+	{ L"sbc",	1,	0x98,	GB_PARAM_A,				GB_PARAM_REG8_MEMHL,	-1,		0,		0 },
+	{ L"sbc",	2,	0xDE,	GB_PARAM_A,				GB_PARAM_IMMEDIATE,		-1,		-1,		GB_IMMEDIATE_U8 | GB_SUB_IMMEDIATE },
 //	{ L"and",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
 //	{ L"xor",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
 //	{ L"or",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
 //	{ L"cp",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
-//	{ L"inc",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
-//	{ L"dec",	1,	0x00,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
+	{ L"inc",	1,	0x04,	GB_PARAM_REG8_MEMHL,	GB_PARAM_NONE,			3,		-1,		0 },
+	{ L"inc",	1,	0x03,	GB_PARAM_REG16_SP,		GB_PARAM_NONE,			4,		-1,		0 },
+	{ L"dec",	1,	0x05,	GB_PARAM_REG8_MEMHL,	GB_PARAM_NONE,			3,		-1,		0 },
+	{ L"dec",	1,	0x0B,	GB_PARAM_REG16_SP,		GB_PARAM_NONE,			4,		-1,		0 },
 	{ L"daa",	1,	0x27,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
 	{ L"cpl",	1,	0x2F,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },
 	{ L"rlca",	1,	0x07,	GB_PARAM_NONE,			GB_PARAM_NONE,			-1,		-1,		0 },

Archs/GB/GameboyOpcodes.h

@@ -45,6 +45,9 @@
 #define GB_IMMEDIATE_U16		0x00000008
 #define GB_STOP					0x00000010
 #define GB_LOAD_REG8_REG8		0x00000020
+#define GB_ADD_IMMEDIATE		0x00000040
+#define GB_SUB_IMMEDIATE		0x00000080
+#define GB_NEGATE_IMM			0x00000100
 
 #define GB_REG_BIT(reg) (1 << reg)