- Moving the fake nullHeader to all memoryManagers

- When checking if a perm object points to a new or old object, I have to discard the machine code objects
- Writing a better test

smalltalksrc/VMMaker/Spur32BitCoMemoryManager.class.st

@@ -199,15 +199,6 @@ Spur32BitCoMemoryManager >> needGCFlagAddress [
 		inSmalltalk: [cogit simulatedReadWriteVariableAddress: #needGCFlag in: self]
 ]
 
-{ #category : #'garbage collection' }
-Spur32BitCoMemoryManager >> nullHeaderForMachineCodeMethod [
-	<api>
-	<returnTypeC: #sqLong>
-	^(self firstLongFormat << self formatShift)
-	+ (1 << self markedBitFullShift)
-	+ ClassBitmapCompactIndex
-]
-
 { #category : #'object enumeration' }
 Spur32BitCoMemoryManager >> objectBytesForSlots: numSlots [
 	"Answer the total number of bytes in an object with the given

smalltalksrc/VMMaker/Spur64BitCoMemoryManager.class.st

@@ -206,15 +206,6 @@ Spur64BitCoMemoryManager >> needGCFlagAddress [
 		inSmalltalk: [cogit simulatedReadWriteVariableAddress: #needGCFlag in: self]
 ]
 
-{ #category : #'garbage collection' }
-Spur64BitCoMemoryManager >> nullHeaderForMachineCodeMethod [
-	<api>
-	<returnTypeC: #sqLong>
-	^(self firstLongFormat << self formatShift)
-	+ (1 << self markedBitFullShift)
-	+ ClassBitmapCompactIndex
-]
-
 { #category : #'object enumeration' }
 Spur64BitCoMemoryManager >> objectBytesForSlots: numSlots [
 	"Answer the total number of bytes in an object with the given

smalltalksrc/VMMaker/SpurMemoryManager.class.st

@@ -9538,6 +9538,15 @@ SpurMemoryManager >> nonIndexablePointerFormat [
 	^1
 ]
 
+{ #category : #'garbage collection' }
+SpurMemoryManager >> nullHeaderForMachineCodeMethod [
+	<api>
+	<returnTypeC: #sqLong>
+	^(self firstLongFormat << self formatShift)
+	+ (1 << self markedBitFullShift)
+	+ ClassBitmapCompactIndex
+]
+
 { #category : #'object access' }
 SpurMemoryManager >> num16BitUnitsOf: objOop [ 
 	"Answer the number of 16-bit units in the given non-immediate object.
@@ -10285,12 +10294,13 @@ SpurMemoryManager >> possiblePermObjectStoreInto: destObj value: valueObj [
 		ifFalse: [ ^ self ].
 
 	(self getMemoryMap isPermanentObject: valueObj) 
-		ifFalse: [ ^ self ].
+		ifTrue: [ ^ self ].
 
 	(self isFixedKnownObject: valueObj)
 		ifTrue: [ ^ self ].
 
-	self assert: (self isInObjectMemory: valueObj).
+	(self isInObjectMemory: valueObj)
+		ifFalse: [ ^ self ].
 
 	self getFromPermToNewSpaceRememberedSet remember: destObj.
 ]

smalltalksrc/VMMakerTests/VMPermanentSpaceMemoryTest.class.st

@@ -653,7 +653,7 @@ VMPermanentSpaceMemoryTest >> testPermanentObjectPointingToTrueIsNotRemembered [
 VMPermanentSpaceMemoryTest >> testPermanentObjectPointingToYoungObjectIsRemovedWhenPointingToMachineCodeMethod [
 
 
-	| oldObject permanentObject youngObject |
+	| oldObject permanentObject youngObject fakeMachineCodeMethod |
 	oldObject := self newOldSpaceObjectWithSlots: 1.
 	youngObject := self newZeroSizedObject.
 	memory storePointer: 0 ofObject: oldObject withValue: youngObject.
@@ -662,13 +662,22 @@ VMPermanentSpaceMemoryTest >> testPermanentObjectPointingToYoungObjectIsRemovedW
 	self assert: (memory isRemembered: permanentObject).
 	self assert: (memory getFromPermToNewSpaceRememberedSet isInRememberedSet: permanentObject ).	
 
-	memory storePointer: 0 ofObject: permanentObject withValue: 16.
+	"We allocate some memory in the codeZone. 
+	Also we set the null header for the machineCodeMethods, this is used to threat references to it as other objects.
+	For example, check the header to see if it is a forwarder, a machine code method is never a forwarder."
+
+	fakeMachineCodeMethod := (VMMemoryMapConfiguration forWordsize: wordSize) new codeZoneInitialAddress.
+	memory memoryManager allocate: 32 desiredPosition: fakeMachineCodeMethod.
+	memory unsignedLong64At: fakeMachineCodeMethod put: memory nullHeaderForMachineCodeMethod.
+
+	"We update the permanent object with the value as if it was a CompiledMethod with a corresponding MachineCodeMethod"	
+	memory storePointer: 0 ofObject: permanentObject withValue: fakeMachineCodeMethod.
 
 	memory doScavenge: 1.
 
 	self deny: (memory isRemembered: permanentObject).
 	self deny: (memory getFromPermToNewSpaceRememberedSet isInRememberedSet: permanentObject ).	
-
+	self assert: (memory fetchPointer: 0 ofObject: permanentObject ) equals: fakeMachineCodeMethod.
 ]
 
 { #category : #'test - moving' }