From 2f31b4d19d03d782a43d3695efe3e1c74562e378 Mon Sep 17 00:00:00 2001
From: Xun Yang <x299yang@uwaterloo.ca>
Date: Sun, 12 Apr 2020 16:20:05 -0400
Subject: [PATCH] subtype testing table
---
AstBuilding.py | 30 ++++++++++++++++++++----------
TypeNodes.py | 44 ++++++++++++++++++++++++++++++++------------
2 files changed, 52 insertions(+), 22 deletions(-)
diff --git a/AstBuilding.py b/AstBuilding.py
index b67b81e..e3382ba 100644
--- a/AstBuilding.py
+++ b/AstBuilding.py
@@ -62,26 +62,36 @@ def reachabilityChecking(ASTs):
# (also simultaneosly creating fieldOffset because fieldOffset table is required to generate size)
def codeGenPrep(ASTs):
interM = []
+ types = []
+
for t in ASTs:
classInterNode = t[1].typeDcl
- if classInterNode and classInterNode.__class__.__name__ == "ClassNode":
+ types.append(classInterNode)
+ if classInterNode.__class__.__name__ == "ClassNode":
classInterNode.populateSizeAndFieldOffset()
else: # interfaceNode, get their methods to prep for SIT
interM += classInterNode.methods
- if interM: # prep SIT
- for i in range(len(interM)):
- interM[i].methodOffset = i * 4
- interM[i].isInterM = True
- for t in ASTs:
- classInterNode = t[1].typeDcl
- if classInterNode and classInterNode.__class__.__name__ == "ClassNode":
- classInterNode.SITsize = len(interM)
+ # prep SIT
+ for i in range(len(interM)):
+ interM[i].methodOffset = i * 4
+ interM[i].isInterM = True
+
+ # prep subtype testing table
+ for i in range(len(types)):
+ types[i].subTypeOffset = i * 4 # assign each type a position in the subtype testing table
+
+ # store SIT and subtype table size
+ for t in ASTs:
+ classInterNode = t[1].typeDcl
+ if classInterNode.__class__.__name__ == "ClassNode":
+ classInterNode.SITsize = len(interM)
+ classInterNode.subTypeSize = len(types)
def codeGen(ASTs, output="output"):
- ASTs = ASTs[:10] # TOREMOVE: don't compile stdlib for now
codeGenPrep(ASTs)
+ ASTs = ASTs[:1] # TOREMOVE: don't compile stdlib for now
for t in ASTs:
t[1].codeGen()
# Outputting the generated code into className.s
diff --git a/TypeNodes.py b/TypeNodes.py
index e316f54..aeec090 100644
--- a/TypeNodes.py
+++ b/TypeNodes.py
@@ -17,6 +17,8 @@ class ClassInterNode(ASTNode):
self.children = []
self.canonName = ''
self.SITsize = 0
+ self.subTypeSize = 0
+ self.subTypeOffset = 0
# sets
self.inherits = []
@@ -310,7 +312,6 @@ class ClassNode(ClassInterNode):
if hasattr(self, "code"):
return
-
self.code = "" # For read-only section
self.data = "" # For writeable data section
# print("This is the super class: {}".format(self.superClass))
@@ -324,10 +325,12 @@ class ClassNode(ClassInterNode):
self.data += self.label
# SIT
- self.data += pLabel("SIT_spot_"+ self.name, "inter") # type 'inter' for interface methods
+ self.data += pLabel("SIT_spot_"+ self.name, "inter") # type 'inter' for internal usage
self.data += p("dd", "42")
- # TODO: subtype testing tables
+ # subtype testing table
+ self.data += pLabel("subT_spot_"+ self.name, "inter") # type 'inter' for internal usage
+ self.data += p("dd", "42")
####### ADDING METHODS TO CLASS MEMORY LAYOUT AND FIELDS TO FIELD OFFSET TABLE #########
# Copying over the offsets of methods from superclass and DECLARING memory segment for the methods
@@ -381,6 +384,12 @@ class ClassNode(ClassInterNode):
self.data += pLabel("SIT_" + str(i), "inter")
self.data += p("dd", "42")
+ # Layout subtype testing column
+ self.data += pLabel("subT_" + self.name, "inter")
+ for i in range(self.subTypeSize):
+ self.data += pLabel("subT_" + str(i), "inter")
+ self.data += p("dd", "0") # 0 for False, 1 for True
+
self.data += ";END OF CLASS MEMORY LAYOUT FOR CLASS " + self.name + "\n"
@@ -423,19 +432,21 @@ class ClassNode(ClassInterNode):
self.code += p("mov", "[eax]", "dword " + imLabel)
self.code += "; End of fill in SIT.\n"
- self.code += p(instruction="ret", arg1="")
- self.code += "; End of function for filling in class memory layout\n"
-
-
+ # fill in subtype testing column
+ self.code += "\n; Filling in subtype testing\n"
+ self.code += p("mov", "eax", "I_subT_spot_" + self.name)
+ self.code += p("mov", "[eax]", "dword I_subT_" + self.name)
+ for t in getSupers(self): # getSupers includes self
+ dlabel = "I_subT_" + str(t.subTypeOffset // 4)
+ self.code += p("mov", "eax", dlabel, "self is a subType of " + t.canonName)
+ self.code += p("mov", "[eax]", "dword 1")
+ self.code += "; End of fill in subtype testing.\n"
+ self.code += p(instruction="ret", arg1="")
+ self.code += "; End of function for filling in class memory layout\n"
- # print(self.name)
- # print(self.fieldOffset)
-
- # print(self.code)
-
###########################################################
# Generating a function that allocates and initializes all static fields
@@ -552,3 +563,12 @@ def safeReplace(cur, new, className):
# quick fix for final method getClass from java.lang.Object
if 'final' in cur.mods and cur.name != 'getClass':
raise Exception("ERROR: In class {0}, {1} '{2}' in class '{3}' replaces final {1} in class/interface {4}".format(className, methodOrField, new.name, new.typeName, cur.typeName))
+
+
+# helper: get list of all super class/interface of a ClassInterNode
+def getSupers(classType):
+ result = {classType}
+ for s in classType.super:
+ result.add(s)
+ result.union(getSupers(s))
+ return result
--
GitLab