X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/df770340caf8ecd26a55179484edb507082bd5c6..77ab69d7bb0902e6ebf0994159ed2205f8413e34:/insn_ret-retcc.v

diff --git a/insn_ret-retcc.v b/insn_ret-retcc.v
index ef89003..dab27c3 100644
--- a/insn_ret-retcc.v
+++ b/insn_ret-retcc.v
@@ -1,30 +1,20 @@
 `ifdef EXECUTE
 	`INSN_RET,`INSN_RETCC: begin
 		case (cycle)
-		0:	begin
-				rd <= 1;
-				address <= {registers[`REG_SPH],registers[`REG_SPL]};
-			end
+		0:	`EXEC_READ(`_SP)
 		1:	begin	// SPECIAL CASE: cycle does NOT increase linearly with ret!
-				`EXEC_INC_PC;	// cycle 1 is skipped if we are not retcc
+				`EXEC_INC_PC	// cycle 1 is skipped if we are not retcc
 				case (opcode[4:3])
-				`INSN_cc_NZ:	if (registers[`REG_F][7]) begin `EXEC_NEWCYCLE; end
-				`INSN_cc_Z:		if (~registers[`REG_F][7]) begin `EXEC_NEWCYCLE; end
-				`INSN_cc_NC:	if (registers[`REG_F][4]) begin `EXEC_NEWCYCLE; end
-				`INSN_cc_C:		if (~registers[`REG_F][4]) begin `EXEC_NEWCYCLE; end
+				`INSN_cc_NZ:	if (`_F[7])  `EXEC_NEWCYCLE
+				`INSN_cc_Z:	if (~`_F[7]) `EXEC_NEWCYCLE
+				`INSN_cc_NC:	if (`_F[4])  `EXEC_NEWCYCLE
+				`INSN_cc_C:	if (~`_F[4]) `EXEC_NEWCYCLE
 				endcase
-				rd <= 1;
-				address <= {registers[`REG_SPH],registers[`REG_SPL]};
-			end
-		2:	begin
-				rd <= 1;
-				address <= {registers[`REG_SPH],registers[`REG_SPL]} + 1;
+				`EXEC_READ(`_SP)	// retry the read
 			end
+		2:	`EXEC_READ(`_SP + 1)
 		3:	begin /* twiddle thumbs */ end
-		4:	begin
-				`EXEC_NEWCYCLE;
-				// do NOT increment PC!
-			end
+		4:	`EXEC_NEWCYCLE
 		endcase
 	end
 `endif
@@ -35,11 +25,10 @@
 		0:	if (opcode[0])	// i.e., not RETCC
 				cycle <= 1;	// Skip cycle 1; it gets incremented on the next round.
 		1:	begin /* Nothing need happen here. */ end
-		2:	registers[`REG_PCL] <= rdata;
-		3:	registers[`REG_PCH] <= rdata;
+		2:	`_PCL <= rdata;
+		3:	`_PCH <= rdata;
 		4:	begin
-				{registers[`REG_SPH],registers[`REG_SPL]} <=
-					{registers[`REG_SPH],registers[`REG_SPL]} + 2;
+				`_SP <= `_SP + 2;
 				if (opcode[4] && opcode[0])	/* RETI */
 					ie <= 1;
 			end