iurt_lib.vhd

ERC32 经典的sparc v7 cpu

              CurrentAddr := LoadORStoreORSwapAddrCalc(ID, CWP, RegFile);
	    end if;
              
            if IsStoreInst(ID.Mnemo) then
              if (ID.Mnemo = STB or EX.Mnemo = STBA) then
                SizeVar := BYTE;
              elsif (ID.Mnemo = STH or EX.Mnemo = STHA) then
                SizeVar := HALFWORD;
              elsif IsStoreDoubleInst(ID.Mnemo) then
                SizeVar := DOUBLEWORD;
              else
                SizeVar := WORDTYPE;
	      end if;
	    end if;


            if IsStoreInst(EX.Mnemo) then
              -- Size assignment + StoreData value assignment
              DestReg := GetIndex(EX.rd, CWP);
              if (EX.Mnemo = STB or EX.Mnemo = STBA) then
                StoreData(7 downto 0)   := RegFile(DestReg)(7 downto 0);
                StoreData(15 downto 8)  := RegFile(DestReg)(7 downto 0);
                StoreData(23 downto 16) := RegFile(DestReg)(7 downto 0);
                StoreData(31 downto 24) := RegFile(DestReg)(7 downto 0);
              elsif (EX.Mnemo = STH or EX.Mnemo = STHA) then
                StoreData(15 downto 0)  := RegFile(DestReg)(15 downto 0);
                StoreData(31 downto 16) := RegFile(DestReg)(15 downto 0);
              elsif IsStoreDoubleInst(EX.Mnemo) then
                if (EX.Mnemo = I_STD or EX.Mnemo = STDA) then
                  StoreData := RegFile((DestReg/2)*2);
                                       -- even-numbered register: 1st data.
                end if;
              else
                if not(IsStoreFP_CPInst(Ex.Mnemo)) then
                  StoreData := RegFile(DestReg);
                end if;
              end if;
            end if;
            
            if (WR.Mnemo = I_STD or WR.Mnemo = STDA) then
              DestReg := GetIndex(WR.rd, CWP);
              StoreData := RegFile((DestReg/2)*2 + 1); 
                                    -- odd-numbered register: 2nd data.
            end if;
                        
            if ((IsStoreSingleInst(WR.Mnemo) and EX.Mnemo /= ANNULLED) or 
                IsStoreDoubleInst(WR1.Mnemo)) then
              if ( not((IsBicc(nID.Mnemo) or IsFBfcc(nID.Mnemo)) and TakenBr) 
                  and nID.Mnemo /= CALL) then
                CurrentAddr := SaveCurrentAddr; -- Restore values of instruction
                                                -- addresses unless nID=Bicc or
                                                -- nID=FBfcc or nID=CALL
              end if;
              
              if S = '0' then -- restore value of the ASI bus
                ASIvar := USER_INST;
              else
                ASIvar := SUPERVISOR_INST;
              end if;
              
              SizeVar := WORDTYPE;
            end if;
            
            -- ''''''''  LDSTUB & SWAP. '''''''''
            if (ID.Mnemo = LDSTUB or ID.Mnemo = LDSTUBA or ID.Mnemo = SWAP or
                ID.Mnemo = SWAPA) then
              SaveCurrentAddr := CurrentAddr;
              Preserve_SavePrevAddr := SavePrevAddr;
              SavePrevAddr := PrevAddr;
              
              if S = '0' then
                ASIvar := USER_DATA;
              else
                ASIvar := SUPERVISOR_DATA;
              end if;
              if (ID.Mnemo = LDSTUBA or ID.Mnemo = SWAPA) then 
                ASIvar := ID.asi;
              end if;
              
              if (ID.Mnemo = LDSTUBA or ID.Mnemo = LDSTUB) then
                SizeVar := BYTE;
              else
                SizeVar := WORDTYPE;
              end if;
              
              CurrentAddr := LoadORStoreORSwapAddrCalc(ID, CWP, RegFile);
              LoadDataAddr := CurrentAddr;
            end if;
            
            if (EX.Mnemo = LDSTUB or ID.Mnemo = LDSTUBA) then
              StoreData  := (others => '1');
            elsif (WR.Mnemo = SWAP or WR.Mnemo = SWAPA) then
              StoreData := SwapData;
            end if;
            
            if (WR1.Mnemo = LDSTUB or WR1.Mnemo = LDSTUBA or WR1.Mnemo = SWAP or
                WR1.Mnemo = SWAPA) then
              if ( not((IsBicc(nID.Mnemo) or IsFBfcc(nID.Mnemo)) and TakenBr) 
                  and nID.Mnemo /= CALL) then
                CurrentAddr := SaveCurrentAddr; -- Restore values of instruction
                                                -- addresses unless nID=Bicc or
                                                -- nID=FBfcc or nID=CALL
              end if;
              
              if S = '0' then -- restore value of the ASI bus
                ASIvar := USER_INST;
              else
                ASIvar := SUPERVISOR_INST;
              end if;
              
              SizeVar := WORDTYPE;
            end if;
            
            -- ''''''''  JMPL & RETT: branching address calculation. '''''''''
            if ( ID.Mnemo = JMPL or ID.Mnemo = RETT ) then
              JmplRettAddrCalc(ID, CWP, RegFile, CurrentAddr);
            end if;
                        
          end if;
          
          --..... Assignment of variables corresponding to signals .....
          --..... triggered on the rising edge of the clock CLK.   .....
          
          -- Signal ASI --> ASIvar
          if TrapMode /= NOTRAP then 
            ASIvar := SUPERVISOR_INST;
          end if;
          
          -- Signal Size --> SizeVar
          if TrapMode /= NOTRAP then
            SizeVar := WORDTYPE;
          end if;
          
          -- Signal INTACK --> INTACKvar
          pINTACKvar := INTACKvar;
          if ( -- conditions for resetting

-- Fixed to reset one clock earlier, Jiri Gaisler 30-01-96

               ID.Mnemo = ANNULLED and EX.Mnemo = ANNULLED
             ) then
            INTACKvar := '0';
          end if;
          if ( -- conditions for setting
               TriggerINTACK
             ) then
            INTACKvar := '1';
            TriggerINTACK := FALSE;
          end if;
          
          
          -- Signal RD --> RDvar
          pTOpRDvar := pRDvar;
          pRDvar := RDvar;
          if TrapMode /= NOTRAP then
            RDvar := '1';
          else
            if ( -- conditions for setting
                 IsStoreSingleInst(WR.Mnemo) or
                 IsStoreDoubleInst(WR1.Mnemo) or
                 (WR1.Mnemo = LDSTUB or WR1.Mnemo = LDSTUBA) or
                 (WR1.Mnemo = SWAP or WR1.Mnemo = SWAPA)
               ) then
              RDvar := '1';
            end if;
            if ( -- conditions for resetting
                 IsStoreInst(ID.Mnemo) or
                 (EX.Mnemo = LDSTUB or EX.Mnemo = LDSTUBA) or
                 (EX.Mnemo = SWAP or EX.Mnemo = SWAPA)
               ) then
              RDvar := '0';
            end if;
          end if;
          
          -- Signal WE_N --> WE_Nvar
          pTOpWE_Nvar := pWE_Nvar;
          pWE_Nvar := WE_Nvar;
          if TrapMode /= NOTRAP then
            WE_Nvar := '1';
          else
            if ( -- conditions for setting
                 IsStoreSingleInst(WR.Mnemo) or
                 IsStoreDoubleInst(WR1.Mnemo) or
                 (WR1.Mnemo = LDSTUB or WR1.Mnemo = LDSTUBA) or
                 (WR1.Mnemo = SWAP or WR1.Mnemo = SWAPA)
               ) then
              WE_Nvar := '1';
            end if;
            if ( -- conditions for resetting
                 IsStoreInst(EX.Mnemo) or
                 (WR.Mnemo = LDSTUB or WR.Mnemo = LDSTUBA) or
                 (WR.Mnemo = SWAP or WR.Mnemo = SWAPA)
               ) then
              WE_Nvar := '0';
            end if;
          end if;
          
          -- Signal WRT --> WRTvar
          pTOpWRTvar := pWRTvar;
          pWRTvar := WRTvar;
          if TrapMode /= NOTRAP then
            WRTvar := '0';
          else
            if ( -- conditions for resetting
                 IsStoreInst(EX.Mnemo) or
                 (WR.Mnemo = LDSTUB or WR.Mnemo = LDSTUBA) or
                 (WR.Mnemo = SWAP or WR.Mnemo = SWAPA)
               ) then
              WRTvar := '0';
            end if;
            if ( -- conditions for setting
                 IsStoreInst(ID.Mnemo) or
                 (EX.Mnemo = LDSTUB or EX.Mnemo = LDSTUBA) or
                 (EX.Mnemo = SWAP or EX.Mnemo = SWAPA)
               ) then
              WRTvar := '1';
            end if;
          end if;
          
          -- Signal DXFER --> DXFERvar
          pTOpDXFERvar := pDXFERvar;
          pDXFERvar := DXFERvar;
          if TrapMode /= NOTRAP then
            DXFERvar := '0';
          else
            if ( -- conditions for resetting
                 IsLoadSingleInst(EX.Mnemo) or
                 IsLoadDoubleInst(WR.Mnemo) or
                 IsStoreSingleInst(WR.Mnemo) or
                 IsStoreDoubleInst(WR1.Mnemo) or
                 (WR1.Mnemo = LDSTUB or WR1.Mnemo = LDSTUBA) or
                 (WR1.Mnemo = SWAP or WR1.Mnemo = SWAPA)
               ) then
              DXFERvar := '0';
            end if;
            if ( -- conditions for setting overriding resetting
                 IsLoadInst(ID.Mnemo) or
                 IsStoreInst(ID.Mnemo) or
                 (ID.Mnemo = LDSTUB or ID.Mnemo = LDSTUBA) or
                 (ID.Mnemo = SWAP or ID.Mnemo = SWAPA)
               ) then
              DXFERvar := '1';
            end if;
          end if;
          
          -- Signal LDSTO --> LDSTOvar
          pTOpLDSTOvar := pLDSTOvar;
          pLDSTOvar := LDSTOvar;
          if TrapMode /= NOTRAP then 
            LDSTOvar := '0';
          else
            if ( -- conditions for resetting
                 (WR1.Mnemo = LDSTUB or WR1.Mnemo = LDSTUBA) or
                 (WR1.Mnemo = SWAP or WR1.Mnemo = SWAPA)
               ) then
              LDSTOvar := '0';
            end if;
            if ( -- conditions for setting overriding resetting
                 (ID.Mnemo = LDSTUB or ID.Mnemo = LDSTUBA) or
                 (ID.Mnemo = SWAP or ID.Mnemo = SWAPA)
               ) then
              LDSTOvar := '1';
            end if;
          end if;
          
          -- Signal INULL --> INULLvar
          pINULLvar := INULLvar;
          if TrapMode /= NOTRAP then 
            INULLvar := '1';
          else
            if ( -- conditions for resetting
                 EX.Mnemo = RETT or
                 (EX.Mnemo = JMPL and not(IOPcase)) or
                 (WR.Mnemo = JMPL and ID.Mnemo = IOP) or
                 (ID.Mnemo = ANNULLED and EX.Mnemo = ANNULLED) or
                 (WR.Mnemo = CALL and EX.Mnemo = IOP) or
                 (IsLoadSingleInst(WR1.Mnemo) and EX.Mnemo = IOP) or
                 (IsLoadDoubleInst(WR2.Mnemo) and EX.Mnemo = IOP) or
                 IsStoreInst(WR1.Mnemo) or
                 (WR2.Mnemo = LDSTUB or WR2.Mnemo = LDSTUBA) or
                 (WR2.Mnemo = SWAP or WR2.Mnemo = SWAPA)
               ) then
              INULLvar := '0';
            end if;
            if  ( -- conditions setting overriding resetting
                  ID.Mnemo = JMPL or
                  ID.Mnemo = RETT or
                  (EX.Mnemo = CALL and ID.Mnemo = IOP) or
                  (IsLoadSingleInst(WR.Mnemo) and ID.Mnemo = IOP and 
		   not isFPInst(WR.Mnemo) and not IsFPInst(ID.Mnemo)) or

--                  (IsLoadSingleInst(WR1.Mnemo) and 
--		((WR1.rd = EX.rs1) or ((WR1.rd = EX.rs2) and (EX.i = 0)))) or

                  (IsLoadDoubleInst(WR1.Mnemo) and ID.Mnemo = IOP and
                   not isFPInst(WR1.Mnemo) and not IsFPInst(ID.Mnemo)) or 
                  (IsStoreInst(WR.Mnemo) and EX.Mnemo /= ANNULLED) or
--		   not isFPInst(WR.Mnemo) and not IsFPInst(EX.Mnemo)) or
                  (WR1.Mnemo = LDSTUB or WR1.Mnemo = LDSTUBA) or
                  (WR1.Mnemo = SWAP or WR1.Mnemo = SWAPA)
                ) then
               INULLvar := '1';
            end if;
          end if;
            
          
          -- Signal LOCK -