- removed register output latch (latch introduced global clock buffer, which is deprecated)

- added separate reg_pointer for read/write
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git-svn-id: http://moon:8086/svn/vhdl/trunk@470 cc03376c-175c-47c8-b038-4cd826a8556b

lib/CPUs/MIPS/src/core/mips_cop.vhd

@@ -77,6 +77,8 @@ architecture Behavioral of cop is
 	signal EB_reg			: STD_LOGIC;
 	signal icache_info		: unsigned(7 downto 0);
 	signal dcache_info		: unsigned(7 downto 0);
+	signal reg_rptr			: reg_ptr_t;
+	signal reg_wptr			: reg_ptr_t;
 	
 	type cop_pipe_t is record
 		opc			: opcode_t;
@@ -364,15 +366,22 @@ cop_pipe:
 				cop_pipe_EX.re	<= '0';
 			elsif ctrl_in.sdu.stall_all = '0' then
 				cop_pipe_EX		<= cop_pipe_ID;
+				if cop_pipe_ID.we = '1' then
+					reg_wptr	<= cop_pipe_ID.reg_ptr;
+				end if;
+				if cop_pipe_ID.re = '1' then
+					reg_rptr	<= cop_pipe_ID.reg_ptr;
+				end if;
 			end if;
 		end if;
 	end process;
 
 cop_register_read:
-	process(cop_pipe_EX, BadVAddr, status, cause, epc, dcache_info, icache_info, test_reg)
+	process(reg_rptr, BadVAddr, status, cause, epc, dcache_info, icache_info, test_reg)
 	variable reg : word_t;
 	begin
-		case cop_pipe_EX.reg_ptr is
+	
+		case reg_rptr is
 		when "01000" =>			-- BadVAddr
 			reg	:= BadVAddr;
 
@@ -396,10 +405,7 @@ cop_register_read:
 
 		end case;	
 
-		-- Output latch
-		if cop_pipe_EX.re = '1' then
-			dout	<= reg after 2 ns;
-		end if;	
+		dout	<= reg after 2 ns;
 
 	end process;
 
@@ -420,7 +426,7 @@ cop_we_gen:
 				ip_reg_we	<= '0';
 				if cop_pipe_EX.we = '1' then
 
-					case cop_pipe_EX.reg_ptr is
+					case reg_wptr is
 
 					when "01100" =>
 						stat_reg_we	<= '1'; -- not status(1) or status(28);