alu

code/alu.py

@@ -1,36 +1,92 @@
-import binandint
-def alu(a,b,alu_ctrl):              #a,b为两个运算数，alu_ctrl为控制信号，返回运算结果result与是否为0 zero
-    if alu_ctrl=='00000':
-        pass
-    elif alu_ctrl=='00001':
-        pass
-    elif alu_ctrl=='00010':
-        pass
-    elif alu_ctrl=='00011':
-        pass
-    elif alu_ctrl=='00100':
-        pass
-    elif alu_ctrl=='00101':
-        pass
-    elif alu_ctrl=='00110':
-        pass
-    elif alu_ctrl=='00111':
-        pass
-    elif alu_ctrl=='01000':
-        pass
-    elif alu_ctrl=='01001':
-        pass
-    elif alu_ctrl=='01010':
-        pass
-    elif alu_ctrl=='01011':
-        pass
-    elif alu_ctrl=='01100':
-        pass
-    elif alu_ctrl=='01101':
-        pass
-    elif alu_ctrl=='01110':
-        pass
-    elif alu_ctrl=='01111':
-        pass
-    else:
-        pass
+from binandint import *
+def alu(a,b,alu_ctrl):  #a,b为两个运算数，alu_ctrl为控制信号，返回运算结果result与是否为0 zero
+	signed = a-b
+	if alu_ctrl=='00000':           #add,jalr
+		alu_result = a+b
+	elif alu_ctrl=='00001':         #sub
+		alu_result = a-b
+	elif alu_ctrl=='00010':         #or
+		alu_result = a|b
+	elif alu_ctrl=='00011':         #and
+		alu_result = a&b
+	elif alu_ctrl=='00100':         #slt
+		if(signed >= 0):
+			alu_result = 0
+		else:
+			alu_result = 1
+	elif alu_ctrl=='00101':         #beq
+		if a == b:
+			alu_result = 1
+		else:
+			alu_result = 0
+	elif alu_ctrl=='00110':         #bne
+		if a != b:
+			alu_result = 1
+		else:
+			alu_result = 0
+	elif alu_ctrl=='00111':         #blt
+		if a<b:
+			alu_result = 1
+		else:
+			alu_result = 0
+	elif alu_ctrl=='01000':         #bge
+		if a>=b:
+			alu_result = 1
+		else:
+			alu_result = 0
+	elif alu_ctrl=='01001':
+		if a<0:
+			ua = a+2**32
+		else:
+			ua=a
+		if b<0:
+			ub = b+2**32
+		else:
+			ub=b
+		if ua < ub:
+			alu_result = 1
+		else:
+			alu_result = 0
+	elif alu_ctrl=='01010':
+		if a<0:
+			ua = a+2**32
+		else:
+			ua=a
+		if b<0:
+			ub = b+2**32
+		else:
+			ub=b
+		if ua >= ub:
+			alu_result = 1
+		else:
+			alu_result = 0
+	elif alu_ctrl=='01011':
+		alu_result = 1
+	elif alu_ctrl=='01100':
+		alu_result = a^b
+	elif alu_ctrl=='01101':
+	 	alu_result=a<<b
+	elif alu_ctrl=='01110':
+		if a<0:
+			ua = a+2**32
+		else:
+			ua=a
+		if b<0:
+			ub = b+2**32
+		else:
+			ub=b
+		if ua <= ub:
+			alu_result = 1
+		else:
+			alu_result = 0        
+	elif alu_ctrl=='01111':
+		if a<0:
+			ua = a+2**32
+		else:
+			ua=a
+	 	alu_result=a>>b
+	elif alu_ctrl=='10000':
+	 	alu_result=a>>b
+	else:
+		alu_result = 0
+	return alu_result