From f2b745a710572fd5cb2b1cf97d1d05a9b74d4fe1 Mon Sep 17 00:00:00 2001
From: Joshua Wise <joshua@rebirth.joshuawise.com>
Date: Tue, 8 Apr 2008 15:52:11 -0400
Subject: [PATCH 1/1] INC -> INCDEC

---
 GBZ80Core.v        |  2 ++
 allinsns.v         |  2 ++
 insn_incdec_hl.v   | 18 ++++++++++++++++++
 insn_incdec_reg8.v | 29 +++++++++++++++++++++++++++++
 4 files changed, 51 insertions(+)
 create mode 100644 insn_incdec_hl.v
 create mode 100644 insn_incdec_reg8.v

diff --git a/GBZ80Core.v b/GBZ80Core.v
index af5574f..33e7be6 100644
--- a/GBZ80Core.v
+++ b/GBZ80Core.v
@@ -69,6 +69,8 @@
 `define INSN_VOP_INTR		8'b11111100	// 0xFC is grabbed by the fetch if there is an interrupt pending.
 `define INSN_DI			8'b11110011
 `define INSN_EI			8'b11111011
+`define INSN_INCDEC_HL		8'b0011010x
+`define INSN_INCDEC_reg8	8'b00xxx10x
 
 `define INSN_cc_NZ		2'b00
 `define INSN_cc_Z		2'b01
diff --git a/allinsns.v b/allinsns.v
index fbcca50..0b2e51c 100644
--- a/allinsns.v
+++ b/allinsns.v
@@ -21,3 +21,5 @@
 `include "insn_incdec16.v"
 `include "insn_vop_intr.v"
 `include "insn_di-ei.v"
+`include "insn_incdec_hl.v"
+`include "insn_incdec_reg8.v"
\ No newline at end of file
diff --git a/insn_incdec_hl.v b/insn_incdec_hl.v
new file mode 100644
index 0000000..abfe495
--- /dev/null
+++ b/insn_incdec_hl.v
@@ -0,0 +1,18 @@
+`ifdef EXECUTE
+	`INSN_INCDEC_HL: begin
+		case (cycle)
+		0:	`EXEC_READ(`_HL)
+		1:	`EXEC_WRITE(`_HL, rdata + (opcode[0] ? 8'hFF : 8'h01))
+		2:	begin
+				`EXEC_INC_PC
+				`EXEC_NEWCYCLE
+			end
+		endcase
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_INCDEC_HL: begin
+		/* meh meh */
+	end
+`endif
diff --git a/insn_incdec_reg8.v b/insn_incdec_reg8.v
new file mode 100644
index 0000000..78f8b5a
--- /dev/null
+++ b/insn_incdec_reg8.v
@@ -0,0 +1,29 @@
+`ifdef EXECUTE
+	`INSN_INCDEC_reg8: begin
+		`EXEC_INC_PC
+		`EXEC_NEWCYCLE
+		case (opcode[5:3])
+		`INSN_reg_A:	tmp <= `_A;
+		`INSN_reg_B:	tmp <= `_B;
+		`INSN_reg_C:	tmp <= `_C;
+		`INSN_reg_D:	tmp <= `_D;
+		`INSN_reg_E:	tmp <= `_E;
+		`INSN_reg_H:	tmp <= `_H;
+		`INSN_reg_L:	tmp <= `_L;
+		endcase
+	end
+`endif
+
+`ifdef WRITEBACK
+	`INSN_INCDEC_reg8: begin
+		case (opcode[5:3])
+		`INSN_reg_A:	`_A <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		`INSN_reg_B:	`_B <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		`INSN_reg_C:	`_C <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		`INSN_reg_D:	`_D <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		`INSN_reg_E:	`_E <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		`INSN_reg_H:	`_H <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		`INSN_reg_L:	`_L <= tmp + (opcode[0] ? 8'hFF : 8'h01);
+		endcase
+	end
+`endif
-- 
2.43.0