refactor dir structure, add fib.c

1 files changed, 0 insertions, 155 deletions

diff --git a/PIC/decoder.vhd b/PIC/decoder.vhd
deleted file mode 100644
index 5a1eb2c..0000000
--- a/PIC/decoder.vhd
+++ /dev/null
@@ -1,155 +0,0 @@
-library ieee;
-use ieee.std_logic_1164.all;
-use work.alu_types.all;
-
-package decoder is
-  type instruction_class_t is (
-    BIT_OP,
-    BYTE_OP,
-    LITERAL_OP,
-    CONTROL_OP,
-    UNKNOWN
-    );
-
-  type instruction_t is record
-    class : instruction_class_t;
-    op    : alu_op;
-    f     : std_logic_vector(6 downto 0);
-    b     : std_logic_vector(2 downto 0);
-    d     : std_logic;
-    k     : std_logic_vector(10 downto 0);
-  end record;
-
-  pure function instruction_get_class(opc : std_logic_vector(13 downto 0)) return instruction_class_t;
-
-  pure function instruction_get_operation(
-    opc         : std_logic_vector(13 downto 0);
-    instr_class : instruction_class_t)
-    return alu_op;
-
-  pure function instruction_decode(opc : std_logic_vector(13 downto 0)) return instruction_t;
-
-end package;
-
-package body decoder is
-
-  pure function instruction_decode(opc : std_logic_vector(13 downto 0))
-    return instruction_t is
-    variable instr : instruction_t;
-  begin
-    instr.class := instruction_get_class(opc);
-    instr.op    := instruction_get_operation(opc, instr.class);
-
-    instr.f := (others => '0');
-    instr.b := (others => '0');
-    instr.d := '0';
-    instr.k := (others => '0');
-
-    case instr.class is
-      when BIT_OP =>
-        instr.b := opc(9 downto 7);
-        instr.f := opc(6 downto 0);
-      when BYTE_OP =>
-        instr.f := opc(6 downto 0);
-        instr.d := opc(7);
-      when LITERAL_OP | CONTROL_OP =>
-        instr.k := opc(10 downto 0);
-      when UNKNOWN =>
-    end case;
-
-    return instr;
-  end function;
-
-  pure function instruction_get_class(opc : std_logic_vector(13 downto 0))
-    return instruction_class_t is
-  begin
-    -- RETURN (0x0008) has bits[13:12]="00" but must be treated as LITERAL_OP
-    if opc = "00000000001000" then return LITERAL_OP; end if;
-    case opc(13 downto 12) is
-      -- byte-oriented file-register operations
-      when "00" =>
-        return BYTE_OP;
-      when "01" =>
-        return BIT_OP;
-      when "10" =>
-        return CONTROL_OP;
-      when "11" =>
-        return LITERAL_OP;
-      when others =>
-        return UNKNOWN;
-    end case;
-  end function;
-
-  pure function instruction_get_operation(
-    opc         : std_logic_vector(13 downto 0);
-    instr_class : instruction_class_t)
-    return alu_op is
-  begin
-    case instr_class is
-
-      when BYTE_OP =>
-        case opc(11 downto 8) is
-          when "0000" =>
-            if opc(7) = '1' then return MOVWF;
-            else return NOP;
-            end if;
-          when "0001" =>
-            if opc(7) = '1' then return CLRF;
-            else return CLRW;
-            end if;
-          when "0010" => return SUBWF;
-          when "0011" => return DECF;
-          when "0100" => return IORWF;
-          when "0101" => return ANDWF;
-          when "0110" => return XORWF;
-          when "0111" => return ADDWF;
-          when "1000" => return MOVF;
-          when "1001" => return COMF;
-          when "1010" => return INCF;
-          when "1011" => return DECFSZ;
-          when "1100" => return RRF;
-          when "1101" => return RLF;
-          when "1110" => return SWAPF;
-          when "1111" => return INCFSZ;
-          when others => return NOP;
-        end case;
-
-      when BIT_OP =>
-        case opc(11 downto 10) is
-          when "00"   => return BCF;
-          when "01"   => return BSF;
-          when "10"   => return BTFSC;
-          when "11"   => return BTFSS;
-          when others => return NOP;
-        end case;
-
-      when CONTROL_OP =>
-        if opc(11) = '1' then return GOTO;
-        else return CALL;
-        end if;
-
-      when LITERAL_OP =>
-        -- fixed full-word patterns first (fall inside 00xx space)
-        -- if opc(11 downto 0) = "000000000001" then return RETFIE;
-        if opc(11 downto 0) = "000000001000" then return RETUR;
-        -- elsif opc(11 downto 0) = "000000000011" then return SLEEP;
-        -- elsif opc(11 downto 0) = "000000000100" then return CLRWDT;
-        else
-          case? opc(11 downto 8) is
-            when "00--" => return MOVLW;
-            when "01--" => return RETLW;
-            when "1000" => return IORLW;
-            when "1001" => return ANDLW;
-            when "1010" => return XORLW;
-            when "110-" => return SUBLW;
-            when "111-" => return ADDLW;
-            when others => return NOP;
-          end case?;
-        end if;
-
-      when others => return NOP;
-
-    end case;
-  end function;
-
-end decoder;