register branch (untested) + de1 top level fix

[calu.git] / cpu / src / decoder_b.vhd

diff --git a/cpu/src/decoder_b.vhd b/cpu/src/decoder_b.vhd
index c51e1318ba0ee63d474a5c6799895234c3cb03a8..525d408170a0b6b5bca6b12cfe42ec07f85df0e1 100644 (file)
--- a/cpu/src/decoder_b.vhd
+++ b/cpu/src/decoder_b.vhd
@@ -369,20 +369,47 @@ begin
                        instr_s.immediate(31 downto 16) := (others => '1');
                end if;
 
-               if (instr_s.jmptype = "00") then
---                     instr_s.op_detail(SUB_OPT) := not instr_s.opcode(0);
-                       instr_s.op_group := JMP_OP;
-               end if;
+               case instr_s.jmptype is 
+                       when "00" =>
+                               instr_s.op_group := JMP_OP;
+                       
+                       when "01" =>
+                               instr_s.op_group := JMP_ST_OP;
+                       
+                       when "10" =>
+                               instr_s.op_group := JMP_ST_OP;
+                               instr_s.op_detail(RET_OPT) := '1';
+                       
+                       when "11" =>
+                               instr_s.op_group := JMP_OP;
+                               instr_s.op_detail(JMP_REG_OPT) := '1';
+                               instr_s.op_detail(IMM_OPT) := '1';
+                               instr_s.immediate := (others => '0');
+                       
+                       when others => null;
+               end case;
                
-               if (instr_s.jmptype = "01") then
-                       instr_s.op_group := JMP_ST_OP;
-               --      instr_s.op_detail(RET_OPT) := '0';
-               end if;
-
-               if (instr_s.jmptype = "10") then
-                       instr_s.op_group := JMP_ST_OP;
-                       instr_s.op_detail(RET_OPT) := '1';
-               end if;
+--             if (instr_s.jmptype = "00") then
+----                   instr_s.op_detail(SUB_OPT) := not instr_s.opcode(0);
+--                     instr_s.op_group := JMP_OP;
+--             end if;
+--             
+--             if (instr_s.jmptype = "01") then
+--                     instr_s.op_group := JMP_ST_OP;
+--             --      instr_s.op_detail(RET_OPT) := '0';
+--             end if;
+--
+--             if (instr_s.jmptype = "10") then
+--                     instr_s.op_group := JMP_ST_OP;
+--                     instr_s.op_detail(RET_OPT) := '1';
+--             end if;
+--             
+--             if (instr_s.jmptype = "11") then
+--                     instr_s.op_group := JMP_OP;
+--                     instr_s.op_detail(JMP_REG_OPT) := '1';
+--                     instr_s.op_detail(IMM_OPT) := '1';
+--                     instr_s.immediate := (others => '0');
+--             end if;
 
                if (instr_s.predicates = "1111" or instr_s.jmptype = "10") then
                        instr_s.bp := '0';