Start to implement the CFG

Author: jecisc

src/FAST-Python-Model/FASTPyExpression.class.st

@@ -126,6 +126,14 @@ FASTPyExpression >> collectionInitializer: anObject [
 	collectionInitializer := anObject
 ]
 
+{ #category : 'testing' }
+FASTPyExpression >> isExpressionStatement [
+
+	self containersDo: [ :container | (container isOfType: FASTTStatementBlock) ifTrue: [ ^ true ] ].
+
+	^ false
+]
+
 { #category : 'accessing' }
 FASTPyExpression >> parentAssertStatement [
 	"Relation named: #parentAssertStatement type: #FASTPyAssertStatement opposite: #expressions"

src/FAST-Python-Model/FASTPyModel.class.st

@@ -20,3 +20,9 @@ FASTPyModel class >> annotation [
 	<package: #'FAST-Python-Model'>
 	<generated>
 ]
+
+{ #category : 'as yet unclassified' }
+FASTPyModel >> allFunctionDefinitions [
+
+	^ self allWithType: FASTPyFunctionDefinition
+]

src/FAST-Python-Tools-Tests/FASTPythonCFGTest.class.st

@@ -12,7 +12,8 @@ Class {
 { #category : 'running' }
 FASTPythonCFGTest >> buildCFGFor: aString [
 
-	startBlock := builder buildCFGForModel: (self parse: aString) rootEntities anyOne
+	self flag: #todo. "What should be the entry point?"
+	startBlock := builder buildCFGForModel: (self parse: aString) allFunctionDefinitions first
 ]
 
 { #category : 'running' }
@@ -30,11 +31,20 @@ FASTPythonCFGTest >> setUp [
 	builder := FASTPythonCFGBuilder new
 ]
 
+{ #category : 'tests' }
+FASTPythonCFGTest >> testFunctionWithIf [
+
+	self buildCFGFor: 'def funct():
+	print("Hello")'.
+	self skip.
+	self halt
+]
+
 { #category : 'tests' }
 FASTPythonCFGTest >> testFunctionWithOneStatement [
 
 	self buildCFGFor: 'def funct():
-	return 3'.
+	print("Hello")'.
 
 	self halt
 ]

src/FAST-Python-Tools/FASTPythonCFGBuilder.class.st

@@ -13,5 +13,5 @@ Class {
 FASTPythonCFGBuilder >> initialize [
 
 	super initialize.
-	cfgVisitor := FASTPythonCFGVisitor new
+	self cfgVisitor: FASTPythonCFGVisitor new
 ]

src/FAST-Python-Tools/FASTPythonCFGVisitor.class.st

@@ -1,9 +1,48 @@
 Class {
 	#name : 'FASTPythonCFGVisitor',
-	#superclass : 'Object',
-	#traits : 'FASTTCFGVisitor + FASTPyTVisitor',
-	#classTraits : 'FASTTCFGVisitor classTrait + FASTPyTVisitor classTrait',
+	#superclass : 'FASTPythonVisitor',
+	#traits : 'FASTTCFGVisitor',
+	#classTraits : 'FASTTCFGVisitor classTrait',
 	#category : 'FAST-Python-Tools-CFG/DataFlow',
 	#package : 'FAST-Python-Tools',
 	#tag : 'CFG/DataFlow'
 }
+
+{ #category : 'visiting' }
+FASTPythonCFGVisitor >> visitFASTPyExpression: aFASTPyExpression [
+	"We ignore expressions that are not in a statement block"
+
+	aFASTPyExpression isExpressionStatement ifTrue: [ ^ super visitFASTPyExpression: aFASTPyExpression ]
+]
+
+{ #category : 'visiting' }
+FASTPythonCFGVisitor >> visitFASTPyFunctionDefinition: aFunction [
+
+	super visitFASTPyFunctionDefinition: aFunction.
+
+	cfgBuilder basicBlocks first isStart: true.
+
+	"case where method has no return instruction (void signature)"
+	cfgBuilder currentBlock ifNotNil: [ cfgBuilder chainPendingBlocksTo: FASTNullBlock new ]
+]
+
+{ #category : 'visiting' }
+FASTPythonCFGVisitor >> visitFASTTStatement: aStatement [
+
+	| currentBlock |
+	cfgBuilder currentBlock ifNil: [ cfgBuilder newBasicBlock: FASTBasicBlock ].
+
+	currentBlock := cfgBuilder currentBlock.
+
+	super visitFASTTStatement: aStatement.
+
+	"only adding statement if no expression made changes to the CFG"
+	currentBlock = cfgBuilder currentBlock ifTrue: [ cfgBuilder currentBlock addStatement: aStatement ]
+]
+
+{ #category : 'visiting' }
+FASTPythonCFGVisitor >> visitFASTTStatementBlock: aFASTTStatementBlock [
+	"We do not consider the block as a statemert."
+
+	self visitCollection: aFASTTStatementBlock statements
+]

src/FAST-Python-Visitor/FASTPythonVisitor.class.st

@@ -0,0 +1,11 @@
+"
+I am a basic top down visitor for a FAST Python model.
+"
+Class {
+	#name : 'FASTPythonVisitor',
+	#superclass : 'Object',
+	#traits : 'FASTPyTVisitor',
+	#classTraits : 'FASTPyTVisitor classTrait',
+	#category : 'FAST-Python-Visitor',
+	#package : 'FAST-Python-Visitor'
+}