added ThreeAddressCode class

1 files changed, 50 insertions, 0 deletions

diff --git a/src/back/tac.py b/src/back/tac.py
new file mode 100644
index 0000000..2b288f8
--- /dev/null
+++ b/src/back/tac.py
@@ -0,0 +1,50 @@
+class Op(object):
+    __slots__ = ["name"]
+
+    def __init__(self, name):
+        self.name = name
+
+    def __str__(self):
+        return self.name
+
+    def __repr__(self):
+        return "<Tag: %s>" % self
+
+
+Op.ADD      = Op("ADD") # x = y + z   -> y z x
+Op.SUB      = Op("SUB") # x = y - z   -> y z x
+Op.MUL      = Op("MUL") # x = y * z   -> y z x
+Op.DIV      = Op("DIV") # x = y / z   -> y z x
+Op.MOD      = Op("MOD") # x = y % z   -> y z x
+Op.AND      = Op("AND") # x = y AND z -> y z x
+Op.OR       = Op("OR")  # x = y OR z  -> y z x
+
+Op.NOT      = Op("NOT") # x = !y      -> y None x
+Op.MINUS    = Op("MINUS") # x = - y   -> y None x
+
+Op.ASSIGN   = Op("ASSIGN") # x = y    -> y None x
+
+Op.JMP      = Op("JMP") # "goto" x           -> x
+Op.BEQ      = Op("BEQ") # "if y == z" goto x -> y z x
+Op.BNE      = Op("BNE") # "if y != z" goto x -> y z x
+Op.BLE      = Op("BLE") # ...
+Op.BGE      = Op("BGE")
+Op.BLT      = Op("BLT")
+Op.BGT      = Op("BGT")
+
+Op.PARAM    = Op("PARAM") # param x -> x
+Op.CALL     = Op("CALL")  # fun y (z-args..) -> y z
+Op.RETURN   = Op("RETURN") # return x -> x
+
+Op.ARRAYGET = Op("ARRAYGET") # x = y[i] -> y i x
+Op.ARRAYSET = Op("ARRAYSET") # x[i] = y -> y i x
+
+
+class ThreeAddressCode:
+
+    def __init__(self,op,arg1=None,arg2=None,result=None):
+        self.op = op
+        self.arg1 = arg1
+        self.arg2 = arg2
+        self.result = result
+