diff --git a/Druid-Tests/DRDeadCodeEliminationTest.class.st b/Druid-Tests/DRDeadCodeEliminationTest.class.st
index a8fd5c1f..8f8f5dbe 100644
--- a/Druid-Tests/DRDeadCodeEliminationTest.class.st
+++ b/Druid-Tests/DRDeadCodeEliminationTest.class.st
@@ -4,13 +4,17 @@ Class {
 	#category : #'Druid-Tests-Optimizations'
 }
 
+{ #category : #test }
+DRDeadCodeEliminationTest >> setUp [
+
+	super setUp.
+	optimisation := DRDeadCodeElimination new
+]
+
 { #category : #tests }
 DRDeadCodeEliminationTest >> testDCEOnConditionalJump [
 
-
 	| cfg copy1 copy2 copy3 copy4 copy5 copy6 jump add1 add2 phi|
-	optimisation := DRDeadCodeElimination new. 
-
 	copy1 := DRCopy
 		         operands: { (DRConstantValue value: 1) }
 		         result: (DRTemporaryRegister id: 1).
@@ -58,10 +62,7 @@ DRDeadCodeEliminationTest >> testDCEOnConditionalJump [
 { #category : #tests }
 DRDeadCodeEliminationTest >> testDCEOnDeadEndInstruction [
 
-	| cfg copy1 copy2 phi1|
-	
-	optimisation := DRDeadCodeElimination new. 
-	
+	| cfg copy1 copy2 phi1|	
 	cfg := self setUpCFG: 2. 
 	
 	cfg b1 addInstruction: (DRCopy operands: { DRConstantValue value: 1 } result:  (DRTemporaryRegister id: 1)). 
@@ -87,9 +88,6 @@ DRDeadCodeEliminationTest >> testDCEOnDeadEndInstruction [
 DRDeadCodeEliminationTest >> testDCEOnSeveralBlocs [
 
 	| b1 b2 cfg copy1 |
-	
-	optimisation := DRDeadCodeElimination new. 
-	
 	cfg := self setUpCFG: 2. 
 	
 	b1 := cfg b1.
@@ -107,13 +105,28 @@ DRDeadCodeEliminationTest >> testDCEOnSeveralBlocs [
 	self assert: cfg instructions size equals: 4.
 ]
 
+{ #category : #test }
+DRDeadCodeEliminationTest >> testNotRemoveUnusedMandatoryInstruction [
+
+	| cfg copy addition |
+	cfg := self setUpCFG: 2.
+
+	cfg b2 addInstruction: (copy := DRObjectReferenceCopy
+			         operands:
+			         { (DRObjectReferenceValue expression: 'methodObj') }
+			         result: (DRTemporaryRegister id: 1)).
+	addition := cfg b2 add: copy to: 1.
+
+	optimisation applyTo: cfg.
+
+	self denyCollection: cfg instructions includesAny: { addition }.
+	self assertCollection: cfg instructions includesAny: { copy }
+]
+
 { #category : #test }
 DRDeadCodeEliminationTest >> testRemoveUnusedNoop [
 
 	| cfg |
-	
-	optimisation := DRDeadCodeElimination new. 
-	
 	cfg := self setUpCFG: 2. 
 	
 	cfg b2 addInstruction: (DRNoop new result: DRNoRegister new). 
diff --git a/Druid-Tests/DRLoopTest.class.st b/Druid-Tests/DRLoopTest.class.st
index 469ddc54..0fc0aa59 100644
--- a/Druid-Tests/DRLoopTest.class.st
+++ b/Druid-Tests/DRLoopTest.class.st
@@ -47,7 +47,7 @@ DRLoopTest >> testCanRetrieveLoopGraphWithMultipleBodyBlocks [
 	
 	loopSubgraph := loop loopGraph.
 
-	loopBlocksIds := { 6. 11. 12. 7 }.
+	loopBlocksIds := { 6. 12. 13 . 7 }.
 	self assertCollection: (loopSubgraph blocks collect: #id) hasSameElements: loopBlocksIds.
 ]
 
@@ -78,3 +78,31 @@ DRLoopTest >> testCanRetrieveLoopGraphWithSingleBodyBlock [
 	loopBlocksIds := { 6. 7 }.
 	self assertCollection: (loopSubgraph blocks collect: #id) hasSameElements: loopBlocksIds.
 ]
+
+{ #category : #tests }
+DRLoopTest >> testFixBackjumpsIgnoreInnerRecursivePhis [
+
+	| cfg innerPhi loopHeaderPhi loopBody addition1 addition2 |
+	cfg := self setUpCFGWithConditionalWithPhi.
+
+	loopHeaderPhi := cfg b1 phiWithVariables: {  }.
+	addition1 := cfg b2 add: loopHeaderPhi to: 7.
+
+	innerPhi := cfg b4 phiFunctions unique.
+	innerPhi replaceOperandAtIndex: 1 by: addition1.
+
+	loopBody := cfg newBasicBlock. "5"
+	addition2 := loopBody add: innerPhi to: 8.
+	cfg b4 jumpIfTrueTo: loopBody ifFalseTo: cfg newBasicBlock.
+	loopBody backJumpTo: cfg b1.
+	loopHeaderPhi mergeOperands: { DRNullValue new. addition2 }.
+	cfg validate.
+	
+	self assert: loopHeaderPhi hasRecursiveUse.
+	self assert: innerPhi hasRecursiveUse.
+	self assert: cfg allBackJumps unique equals: loopBody endInstruction.
+	
+	cfg fixBackJumps.
+
+	self assert: cfg allBackJumps unique equals: loopBody endInstruction
+]
diff --git a/Druid-Tests/DRPathGenerationTest.class.st b/Druid-Tests/DRPathGenerationTest.class.st
index 56694691..a9d33edc 100644
--- a/Druid-Tests/DRPathGenerationTest.class.st
+++ b/Druid-Tests/DRPathGenerationTest.class.st
@@ -199,6 +199,29 @@ DRPathGenerationTest >> testConstraintsInferenceFromInnerBranches [
 	self assertConstraint: falseConstraint includes: (DRGreaterOrEqualsConstraint withValue: 20)
 ]
 
+{ #category : #constraints }
+DRPathGenerationTest >> testConstraintsInferenceFromJITExpressions [
+
+	| cfg jitExpression copy |
+	cfg := self setUpCFGWithConditional.
+
+	"Put the JIT expression in a register"
+	jitExpression := cfg b1 jitCompileTimeVariable: 'extB'.
+	copy := cfg b1 copy: jitExpression.
+
+	"Same comparison"
+	cfg b1 endInstruction replaceOperandAtIndex: 1 by: copy.
+	cfg b4
+		jumpIf: copy
+		to: cfg newBasicBlock
+		ifFalseTo: cfg newBasicBlock.
+
+	cfg generatePaths.
+
+	"Sand clock pattern have half of the paths dead"
+	self assert: cfg deadPaths size equals: cfg pathsSize / 2
+]
+
 { #category : #constraints }
 DRPathGenerationTest >> testConstraintsInferenceFromLoop [
 
diff --git a/Druid-Tests/DRProductionBytecodeTest.class.st b/Druid-Tests/DRProductionBytecodeTest.class.st
index 69ddb7e1..f3f9c7e9 100644
--- a/Druid-Tests/DRProductionBytecodeTest.class.st
+++ b/Druid-Tests/DRProductionBytecodeTest.class.st
@@ -1810,9 +1810,11 @@ DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecode7 [
 { #category : #tests }
 DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecode: index [
 
-	| object storeCheckTrampoline |
-	storeCheckTrampoline := self compile: [ cogit RetN: 0 ].
-	cogit ceStoreCheckTrampoline: storeCheckTrampoline.
+	| object fakeTrampoline |
+	fakeTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceStoreCheckTrampoline: fakeTrampoline.
+	cogit ceDeoptimiseFrameTrampoline: fakeTrampoline.
+	cogit bytecodePC: 87.
 
 	self
 		compileBytecode: 200 + index
@@ -1835,13 +1837,58 @@ DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecode: index [
 	self assert: (memory fetchPointer: index ofObject: object) equals: memory trueObject
 ]
 
+{ #category : #tests }
+DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeCallImmutableTrampoline [
+
+	| object value immutableTrampoline fakeTrampoline bytecodePC |
+
+	fakeTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceStoreCheckTrampoline: fakeTrampoline.
+	immutableTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceDeoptimiseFrameTrampoline: immutableTrampoline.
+	bytecodePC := 87.
+	cogit bytecodePC: bytecodePC.
+
+	self
+		compileBytecode: 200
+		selector: #storeAndPopReceiverVariableBytecode
+		thenDo: [ :generator |
+			cogit ssPushRegister: TempReg.
+
+			"Execute the druid's compiled code"
+			generator value.
+
+			"Then return without druid's compiled code"
+			cogit genUpArrowReturn ].
+
+	object := self newObjectWithSlots: 1.	
+	memory setIsImmutableOf: object to: true.
+	
+	value := self newObjectWithSlots: 0.
+
+	machineSimulator temporaryRegisterValue: value.
+
+	self
+		prepareStackForPrimitiveReceiver: object
+		arguments: #(  )
+		method: 0.
+
+	"Should arrive to trampoline to put the object in the remembered set"
+	self runFrom: cogInitialAddress until: immutableTrampoline.
+	
+	self assert: machineSimulator receiverRegisterValue equals: bytecodePC
+]
+
 { #category : #tests }
 DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeCallRememberTrampoline [
 
-	| object value storeCheckTrampoline |
+	| object value storeCheckTrampoline fakeTrampoline |
 
 	storeCheckTrampoline := self compile: [ cogit RetN: 0 ].
 	cogit ceStoreCheckTrampoline: storeCheckTrampoline.
+	fakeTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceDeoptimiseFrameTrampoline: fakeTrampoline.
+	cogit bytecodePC: 87.
 
 	self
 		compileBytecode: 200
@@ -1871,13 +1918,52 @@ DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeCallRememberT
 	self assert: machineSimulator receiverRegisterValue equals: object
 ]
 
+{ #category : #tests }
+DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeImmutable [
+
+	| object value storeCheckTrampoline fakeTrampoline |
+
+	storeCheckTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceStoreCheckTrampoline: storeCheckTrampoline.
+	fakeTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceDeoptimiseFrameTrampoline: fakeTrampoline.
+	cogit bytecodePC: 87.
+
+	self
+		compileBytecode: 200
+		selector: #storeAndPopReceiverVariableBytecode
+		thenDo: [ :generator |
+			cogit ssPushRegister: TempReg.
+
+			"Execute the druid's compiled code"
+			generator value.
+
+			"Then return without druid's compiled code"
+			cogit genUpArrowReturn ].
+
+	object := self newObjectWithSlots: 1.
+	memory setIsImmutableOf: object to: true.
+
+	value := self newObjectWithSlots: 0.
+
+	machineSimulator temporaryRegisterValue: value.
+
+	self executePrimitiveWithReceiver: object.
+
+	self assert: machineSimulator receiverRegisterValue equals: 87.
+	self assert: (memory fetchPointer: 0 ofObject: object) equals: memory nilObject
+]
+
 { #category : #tests }
 DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeNotRemember [
 
-	| object value storeCheckTrampoline |
+	| object value storeCheckTrampoline fakeTrampoline |
 
 	storeCheckTrampoline := self compile: [ cogit RetN: 0 ].
 	cogit ceStoreCheckTrampoline: storeCheckTrampoline.
+	fakeTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceDeoptimiseFrameTrampoline: fakeTrampoline.
+	cogit bytecodePC: 87.
 
 	self
 		compileBytecode: 200
@@ -1905,10 +1991,13 @@ DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeNotRemember [
 { #category : #tests }
 DRProductionBytecodeTest >> testStoreAndPopReceiverVariableBytecodeRemember [
 
-	| object value storeCheckTrampoline |
+	| object value storeCheckTrampoline fakeTrampoline |
 
 	storeCheckTrampoline := self compile: [ cogit RetN: 0 ].
 	cogit ceStoreCheckTrampoline: storeCheckTrampoline.
+	fakeTrampoline := self compile: [ cogit RetN: 0 ].
+	cogit ceDeoptimiseFrameTrampoline: fakeTrampoline.
+	cogit bytecodePC: 87.
 
 	self
 		compileBytecode: 200
diff --git a/Druid-Tests/DRSCCPConstantFoldingTest.class.st b/Druid-Tests/DRSCCPConstantFoldingTest.class.st
index dd35dee6..d18233a3 100644
--- a/Druid-Tests/DRSCCPConstantFoldingTest.class.st
+++ b/Druid-Tests/DRSCCPConstantFoldingTest.class.st
@@ -566,6 +566,30 @@ DRSCCPConstantFoldingTest >> testFoldingLoadWithOperation [
 	self assert: cfg instructions nextToLast operand1 equals: load
 ]
 
+{ #category : #tests }
+DRSCCPConstantFoldingTest >> testFoldingObjectReferenceIntoJITExpression [
+
+	| cfg copy addition |
+	cfg := self setUpCFG: 1.
+
+	cfg b1 addInstruction: (copy := DRObjectReferenceCopy
+			         operands:
+			         { (DRObjectReferenceValue expression: 'methodObj') }
+			         result: (DRTemporaryRegister id: 999)).
+	addition := cfg b1 add: copy to: 1.
+	cfg b1 return: addition.
+
+	optimisation applyTo: cfg.
+
+	"Object references should keep to be annotated for GC"
+	self assert: cfg instructions first equals: copy.
+	"Anyway, users are folded"
+	self assert: cfg instructions second isCopy.
+	self assert: cfg instructions second operand1 expression equals: '(methodObj + 1)'.
+
+
+]
+
 { #category : #tests }
 DRSCCPConstantFoldingTest >> testNonConstantFoldingOf: aClass between: aDROperand1 and: aDROperand2 [ 
 	| cfg |
diff --git a/Druid-Tests/DruidTestRTLCompiler.class.st b/Druid-Tests/DruidTestRTLCompiler.class.st
index 88b3d9e7..3d572f05 100644
--- a/Druid-Tests/DruidTestRTLCompiler.class.st
+++ b/Druid-Tests/DruidTestRTLCompiler.class.st
@@ -203,42 +203,32 @@ DruidTestRTLCompiler >> gen_extPushIntegerBytecode [
 DruidTestRTLCompiler >> gen_extSendSuperBytecode [
 	"AutoGenerated by Druid"
 
-	| live r5 r43 currentBlock |
+	| live r5 r46 currentBlock |
 	live := 0.
 	r5 := extA.
 	extA := 0.
 	BytecodeSetHasDirectedSuperSend=true ifTrue: [
-		| r12 r43 |
+		| r12 r46 |
 		r12 := extB.
 		r12>=64 ifTrue: [
-			| r17 |
-			r17 := extB.
-			extB := 0.
-			numExtB := 0.
-			self marshallSendArguments: ((byte1 bitAnd: 7) + ((r17 - 64) << 3)).
-			self
-				genMarshalledSend: ((byte1 >> 3) + (r5 << 5))
-				numArgs: ((byte1 bitAnd: 7) + ((r17 - 64) << 3))
-				sendTable: (directedSendUsesBinding
-								ifTrue: [directedSuperBindingSendTrampolines]
-								ifFalse: [directedSuperSendTrampolines]).
+			self deoptimize.
 			^ 0 ].
-		r43 := extB.
+		r46 := extB.
 		extB := 0.
 		numExtB := 0.
-		self marshallSendArguments: ((byte1 bitAnd: 7) + (r43 << 3)).
+		self marshallSendArguments: ((byte1 bitAnd: 7) + (r46 << 3)).
 		self
 			genMarshalledSend: ((byte1 >> 3) + (r5 << 5))
-			numArgs: ((byte1 bitAnd: 7) + (r43 << 3))
+			numArgs: ((byte1 bitAnd: 7) + (r46 << 3))
 			sendTable: superSendTrampolines.
 		^ 0 ].
-	r43 := extB.
+	r46 := extB.
 	extB := 0.
 	numExtB := 0.
-	self marshallSendArguments: ((byte1 bitAnd: 7) + (r43 << 3)).
+	self marshallSendArguments: ((byte1 bitAnd: 7) + (r46 << 3)).
 	self
 		genMarshalledSend: ((byte1 >> 3) + (r5 << 5))
-		numArgs: ((byte1 bitAnd: 7) + (r43 << 3))
+		numArgs: ((byte1 bitAnd: 7) + (r46 << 3))
 		sendTable: superSendTrampolines.
 	^ 0
 ]
@@ -341,67 +331,59 @@ DruidTestRTLCompiler >> gen_extendedPushBytecode [
 			      ifNone: [ ^ self unknownBytecode ].
 		live := live bitOr: (self registerMaskFor: t0).
 		self genMoveConstant: methodObj R: t0.
-		self
-			ssPushBase: t0
-			offset: (byte1 bitAnd: 63) + LiteralStart << 3 + 8.
+		self ssPushConstant:
+			(coInterpreter int64AtPointer:  ((methodObj + 8) + (((byte1 bitAnd: 63) + LiteralStart) << 3))).
 		^ 0 ].
 	((byte1 >> 6) bitAnd: 3)=3 ifTrue: [
-		| t0 b322 jumpTrue jump1 jumpNext t1 jump3 jump2 t2 |
+		| t0 |
 		t0 := self
 			      allocateRegNotConflictingWith: live
 			      ifNone: [ ^ self unknownBytecode ].
 		live := live bitOr: (self registerMaskFor: t0).
 		self genMoveConstant: methodObj R: t0.
-		self MoveM64: (byte1 bitAnd: 63) + LiteralStart << 3 + 8 r: t0 R: t0.
-		t1 := self
-			      allocateRegNotConflictingWith: live
-			      ifNone: [ ^ self unknownBytecode ].
-		live := live bitOr: (self registerMaskFor: t1).
-		self MoveM64: 0 r: t0 R: t1.
-		self AndCq: 16r3FFFF7 R: t1.
-		self CmpCq: 0 R: t1.
-		jump1 := self JumpZero: 0.
-		self MoveR: t0 R: t1.
-		jump2 := self Jump: 0.
-		currentBlock := self Label.
-		jump1 jmpTarget: currentBlock.
-		self MoveM64: 8 r: t0 R: t1.
-		self MoveR: t1 R: t0.
-		b322 := self Label.
-		self MoveR: t0 R: t1.
-		self AndCq: 7 R: t1.
-		self CmpCq: 0 R: t1.
-		jump1 := self JumpNonZero: 0.
-		self MoveM64: 0 r: t0 R: t1.
-		self AndCq: 16r3FFFF7 R: t1.
-		t2 := self
-			      allocateRegNotConflictingWith: live
-			      ifNone: [ ^ self unknownBytecode ].
-		live := live bitOr: (self registerMaskFor: t2).
-		self MoveR: t1 R: t2.
-		self CmpCq: 0 R: t2.
-		jumpTrue := self JumpZero: 0.
-		self MoveCq: 0 R: t2.
-		jumpNext := self Jump: 0.
-		jumpTrue jmpTarget: self Label.
-		self MoveCq: 1 R: t2.
-		jumpNext jmpTarget: self Label.
-		self CmpCq: 0 R: t1.
-		jump3 := self JumpZero: 0.
-		currentBlock := self Label.
-		jump1 jmpTarget: currentBlock.
-		self MoveR: t0 R: t1.
-		currentBlock := self Label.
-		jump2 jmpTarget: currentBlock.
-		self ssPushBase: t1 offset: ValueIndex << 3 + 8.
-		jump2 := self Jump: 0.
-		currentBlock := self Label.
-		jump3 jmpTarget: currentBlock.
-		self MoveM64: 8 r: t0 R: t2.
-		self MoveR: t2 R: t0.
-		jump3 := self Jump: b322.
-		currentBlock := self Label.
-		jump2 jmpTarget: currentBlock.
+		0=((coInterpreter int64AtPointer:  (coInterpreter int64AtPointer:  ((methodObj + 8) + (((byte1 bitAnd: 63) + LiteralStart) << 3)))) bitAnd: 4194295)
+			ifTrue: [
+				| jumpTrue jumpNext jump1 jump3 b316 t1 jump2 t2 |
+				self
+					MoveCq:
+					(coInterpreter int64AtPointer:  (((coInterpreter int64AtPointer:  ((methodObj + 8) + (((byte1 bitAnd: 63) + LiteralStart) << 3))) + 8) + 0))
+					R: t0.
+				b316 := self Label.
+				t1 := self
+					      allocateRegNotConflictingWith: live
+					      ifNone: [ ^ self unknownBytecode ].
+				live := live bitOr: (self registerMaskFor: t1).
+				self MoveR: t0 R: t1.
+				self AndCq: 7 R: t1.
+				self CmpCq: 0 R: t1.
+				jump1 := self JumpNonZero: 0.
+				self MoveM64: 0 r: t0 R: t1.
+				self AndCq: 16r3FFFF7 R: t1.
+				t2 := self
+					      allocateRegNotConflictingWith: live
+					      ifNone: [ ^ self unknownBytecode ].
+				live := live bitOr: (self registerMaskFor: t2).
+				self MoveR: t1 R: t2.
+				self CmpCq: 0 R: t2.
+				jumpTrue := self JumpZero: 0.
+				self MoveCq: 0 R: t2.
+				jumpNext := self Jump: 0.
+				jumpTrue jmpTarget: self Label.
+				self MoveCq: 1 R: t2.
+				jumpNext jmpTarget: self Label.
+				self CmpCq: 0 R: t1.
+				jump2 := self JumpNonZero: 0.
+				self MoveM64: 8 r: t0 R: t2.
+				self MoveR: t2 R: t0.
+				jump3 := self Jump: b316.
+				currentBlock := self Label.
+				jump1 jmpTarget: currentBlock.
+				jump2 jmpTarget: currentBlock.
+				self ssPushConstant:
+					(coInterpreter int64AtPointer:  (((coInterpreter int64AtPointer:  ((methodObj + 8) + (((byte1 bitAnd: 63) + LiteralStart) << 3))) + 8) + (ValueIndex << 3))).
+				^ 0 ].
+		self ssPushConstant:
+			(coInterpreter int64AtPointer:  (((coInterpreter int64AtPointer:  ((methodObj + 8) + (((byte1 bitAnd: 63) + LiteralStart) << 3))) + 8) + (ValueIndex << 3))).
 		^ 0 ].
 	^ 0
 ]
@@ -1309,9 +1291,9 @@ DruidTestRTLCompiler >> gen_primitiveDivideByConstant [
 	self
 		DivR: ClassReg
 		R: TempReg
-		Quo: ClassReg
-		Rem: TempReg.
-	self MoveR: ClassReg R: ReceiverResultReg.
+		Quo: TempReg
+		Rem: ClassReg.
+	self MoveR: TempReg R: ReceiverResultReg.
 	self genPrimReturn.
 	^ CompletePrimitive
 ]
@@ -2244,9 +2226,9 @@ DruidTestRTLCompiler >> gen_primitiveMod [
 	self
 		DivR: ClassReg
 		R: TempReg
-		Quo: TempReg
-		Rem: ClassReg.
-	self MoveR: ClassReg R: ReceiverResultReg.
+		Quo: ClassReg
+		Rem: TempReg.
+	self MoveR: TempReg R: ReceiverResultReg.
 	self genPrimReturn.
 	^ CompletePrimitive
 ]
@@ -2660,11 +2642,11 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	self
 		DivR: Extra2Reg
 		R: ClassReg
-		Quo: Extra2Reg
-		Rem: ClassReg.
+		Quo: ClassReg
+		Rem: Extra2Reg.
 	self AndCq: 1 R: TempReg.
 	self AddR: TempReg R: SendNumArgsReg.
-	self MoveCq: 0 R: ClassReg.
+	self MoveCq: 0 R: Extra2Reg.
 	self CmpCq: 0 R: Extra0Reg.
 	jump12 := self JumpZero: 0.
 	jump13 := self Jump: 0.
@@ -2673,32 +2655,29 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	jump12 := self Jump: 0.
 	currentBlock := self Label.
 	jump7 jmpTarget: currentBlock.
-	self MoveR: TempReg R: ClassReg.
-	self CmpCq: 2 R: ClassReg.
+	self MoveR: TempReg R: Extra2Reg.
+	self CmpCq: 2 R: Extra2Reg.
 	jumpTrue := self JumpNonZero: 0.
-	self MoveCq: 0 R: ClassReg.
+	self MoveCq: 0 R: Extra2Reg.
 	jumpNext := self Jump: 0.
 	jumpTrue jmpTarget: self Label.
-	self MoveCq: 1 R: ClassReg.
+	self MoveCq: 1 R: Extra2Reg.
 	jumpNext jmpTarget: self Label.
 	self CmpCq: 2 R: TempReg.
 	jump7 := self JumpNonZero: 0.
-	self MoveR: TempReg R: ClassReg.
-	self AddCq: 1 R: ClassReg.
-	self MoveCq: 2 R: Extra2Reg.
+	self MoveR: TempReg R: Extra2Reg.
+	self AddCq: 1 R: Extra2Reg.
+	self MoveCq: 2 R: ClassReg.
 	self
-		DivR: Extra2Reg
-		R: ClassReg
+		DivR: ClassReg
+		R: Extra2Reg
 		Quo: ClassReg
 		Rem: Extra2Reg.
 	self AndCq: 1 R: TempReg.
 	self AddR: TempReg R: SendNumArgsReg.
-	self MoveCq: 0 R: TempReg.
-	self MoveR: ClassReg R: Extra2Reg.
-	self MoveR: TempReg R: ClassReg.
+	self MoveCq: 0 R: Extra2Reg.
 	currentBlock := self Label.
 	jump13 jmpTarget: currentBlock.
-	self MoveR: Extra2Reg R: TempReg.
 	jump13 := self Jump: 0.
 	currentBlock := self Label.
 	jump6 jmpTarget: currentBlock.
@@ -2708,15 +2687,15 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	jump5 jmpTarget: currentBlock.
 	self AndCq: 16rFFFF R: ClassReg.
 	self AddR: TempReg R: ClassReg.
-	self MoveCq: objectMemory nilObject R: TempReg.
-	self MoveR: TempReg R: Extra1Reg.
+	self MoveCq: objectMemory nilObject R: Extra2Reg.
+	self MoveR: Extra2Reg R: Extra1Reg.
 	jump5 := self Jump: 0.
 	currentBlock := self Label.
 	jump4 jmpTarget: currentBlock.
 	self AndCq: 16rFFFF R: ClassReg.
 	self AddR: TempReg R: ClassReg.
-	self MoveCq: objectMemory nilObject R: TempReg.
-	self MoveR: TempReg R: Extra1Reg.
+	self MoveCq: objectMemory nilObject R: Extra2Reg.
+	self MoveR: Extra2Reg R: Extra1Reg.
 	jump4 := self Jump: 0.
 	currentBlock := self Label.
 	jump3 jmpTarget: currentBlock.
@@ -2732,21 +2711,19 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	jump4 jmpTarget: currentBlock.
 	self CmpCq: 0 R: Extra0Reg.
 	jump4 := self JumpZero: 0.
-	self MoveR: ClassReg R: TempReg.
-	self MoveR: Extra1Reg R: ClassReg.
+	self MoveR: Extra1Reg R: Extra2Reg.
 	currentBlock := self Label.
 	jump13 jmpTarget: currentBlock.
-	self MoveR: TempReg R: Extra3Reg.
+	self MoveR: ClassReg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 8 r: SPReg.
 	self MoveR: SendNumArgsReg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 16 r: SPReg.
-	self MoveR: ClassReg R: Extra3Reg.
+	self MoveR: Extra2Reg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 24 r: SPReg.
 	jump13 := self Jump: 0.
 	currentBlock := self Label.
 	jump4 jmpTarget: currentBlock.
-	self MoveR: ClassReg R: Extra2Reg.
-	self MoveR: Extra1Reg R: ClassReg.
+	self MoveR: Extra1Reg R: Extra2Reg.
 	currentBlock := self Label.
 	jump12 jmpTarget: currentBlock.
 	self MoveM32: 4 r: ReceiverResultReg R: Extra0Reg.
@@ -2756,15 +2733,15 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	jump12 := self JumpZero: 0.
 	self CmpCq: 0 R: Extra0Reg.
 	jump4 := self JumpBelow: 0.
-	self MoveR: Extra2Reg R: Extra3Reg.
+	self MoveR: ClassReg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 8 r: SPReg.
 	self MoveR: SendNumArgsReg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 16 r: SPReg.
-	self MoveR: ClassReg R: Extra3Reg.
+	self MoveR: Extra2Reg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 24 r: SPReg.
 	currentBlock := self Label.
 	jump13 jmpTarget: currentBlock.
-	self MoveR: Arg0Reg R: TempReg.
+	self MoveR: Arg0Reg R: ClassReg.
 	self MoveR: ReceiverResultReg R: Extra1Reg.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
 	self CmpCq: 255 R: Extra3Reg.
@@ -2772,28 +2749,28 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
 	self CmpCq: 1 R: Extra3Reg.
 	jump5 := self JumpLess: 0.
-	self MoveCq: 8 R: Extra2Reg.
+	self MoveCq: 8 R: TempReg.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
-	self MulR: Extra3Reg R: Extra2Reg.
+	self MulR: Extra3Reg R: TempReg.
 	jump6 := self Jump: 0.
 	currentBlock := self Label.
 	jump5 jmpTarget: currentBlock.
-	self MoveCq: 8 R: Extra2Reg.
+	self MoveCq: 8 R: TempReg.
 	currentBlock := self Label.
 	jump6 jmpTarget: currentBlock.
-	self AddCq: 8 R: Extra2Reg.
+	self AddCq: 8 R: TempReg.
 	jump6 := self Jump: 0.
 	currentBlock := self Label.
 	jump13 jmpTarget: currentBlock.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
-	self MoveR: Extra3Reg R: Extra2Reg.
-	self ArithmeticShiftRightCq: 56 R: Extra2Reg.
-	self CmpCq: 0 R: Extra2Reg.
+	self MoveR: Extra3Reg R: TempReg.
+	self ArithmeticShiftRightCq: 56 R: TempReg.
+	self CmpCq: 0 R: TempReg.
 	jump13 := self JumpAbove: 0.
-	self MoveCq: 8 R: Extra2Reg.
+	self MoveCq: 8 R: TempReg.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
-	self MulR: Extra3Reg R: Extra2Reg.
-	self AddCq: 16 R: Extra2Reg.
+	self MulR: Extra3Reg R: TempReg.
+	self AddCq: 16 R: TempReg.
 	currentBlock := self Label.
 	jump6 jmpTarget: currentBlock.
 	self MoveAw: objectMemory freeStartAddress R: SendNumArgsReg.
@@ -2801,24 +2778,24 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	self CmpCq: 255 R: Extra3Reg.
 	jump6 := self JumpGreaterOrEqual: 0.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
-	self MoveR: Extra3Reg R: ClassReg.
-	self LogicalShiftLeftCq: 56 R: ClassReg.
+	self MoveR: Extra3Reg R: Extra2Reg.
+	self LogicalShiftLeftCq: 56 R: Extra2Reg.
 	self MoveMw: 16 r: SPReg R: Extra3Reg.
 	self LogicalShiftLeftCq: 24 R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 16 r: SPReg.
 	self MoveMw: 16 r: SPReg R: Extra3Reg.
-	self AddR: Extra3Reg R: ClassReg.
-	self AddR: Extra0Reg R: ClassReg.
-	self OrCq: 0 R: ClassReg.
-	self MoveR: ClassReg M64: 0 r: SendNumArgsReg.
-	self MoveR: SendNumArgsReg R: ClassReg.
+	self AddR: Extra3Reg R: Extra2Reg.
+	self AddR: Extra0Reg R: Extra2Reg.
+	self OrCq: 0 R: Extra2Reg.
+	self MoveR: Extra2Reg M64: 0 r: SendNumArgsReg.
+	self MoveR: SendNumArgsReg R: Extra2Reg.
 	jump5 := self Jump: 0.
 	currentBlock := self Label.
 	jump6 jmpTarget: currentBlock.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
-	self MoveR: Extra3Reg R: ClassReg.
-	self AddCq: 16rFF00000000000000 R: ClassReg.
-	self MoveR: ClassReg M64: 0 r: SendNumArgsReg.
+	self MoveR: Extra3Reg R: Extra2Reg.
+	self AddCq: 16rFF00000000000000 R: Extra2Reg.
+	self MoveR: Extra2Reg M64: 0 r: SendNumArgsReg.
 	self MoveMw: 16 r: SPReg R: Extra3Reg.
 	self LogicalShiftLeftCq: 24 R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 16 r: SPReg.
@@ -2834,13 +2811,13 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	self MoveMw: 16 r: SPReg R: Extra3Reg.
 	self MoveR: Extra3Reg M64: 8 r: SendNumArgsReg.
 	self AddCq: 8 R: SendNumArgsReg.
-	self MoveR: SendNumArgsReg R: ClassReg.
+	self MoveR: SendNumArgsReg R: Extra2Reg.
 	currentBlock := self Label.
 	jump5 jmpTarget: currentBlock.
 	self MoveAw: objectMemory freeStartAddress R: SendNumArgsReg.
-	self AddR: Extra2Reg R: SendNumArgsReg.
+	self AddR: TempReg R: SendNumArgsReg.
 	self MoveR: SendNumArgsReg Aw: objectMemory freeStartAddress.
-	self MoveR: ClassReg R: Extra3Reg.
+	self MoveR: Extra2Reg R: Extra3Reg.
 	self MoveR: Extra3Reg Mw: 32 r: SPReg.
 	jump5 := self Jump: 0.
 	currentBlock := self Label.
@@ -2854,39 +2831,39 @@ DruidTestRTLCompiler >> gen_primitiveNewWithArg [
 	self CmpCq: 0 R: Extra3Reg.
 	jump5 := self JumpZero: 0.
 	self MoveMw: 32 r: SPReg R: Extra3Reg.
-	self MoveR: Extra3Reg R: ClassReg.
-	self AddCq: 8 R: ClassReg.
-	self MoveCq: 8 R: Extra2Reg.
+	self MoveR: Extra3Reg R: Extra2Reg.
+	self AddCq: 8 R: Extra2Reg.
+	self MoveCq: 8 R: TempReg.
 	self MoveMw: 8 r: SPReg R: Extra3Reg.
-	self MulR: Extra3Reg R: Extra2Reg.
+	self MulR: Extra3Reg R: TempReg.
 	self MoveMw: 32 r: SPReg R: Extra3Reg.
 	self MoveR: Extra3Reg R: Extra0Reg.
-	self AddR: Extra2Reg R: Extra0Reg.
+	self AddR: TempReg R: Extra0Reg.
 	self AddCq: 8 R: Extra0Reg.
 	self SubCq: 1 R: Extra0Reg.
 	b986 := self Label.
-	self CmpR: ClassReg R: Extra0Reg.
+	self CmpR: Extra2Reg R: Extra0Reg.
 	jump13 := self JumpGreaterOrEqual: 0.
-	self MoveR: TempReg R: Extra2Reg.
+	self MoveR: ClassReg R: TempReg.
 	self MoveR: Extra1Reg R: SendNumArgsReg.
 	jump6 := self Jump: 0.
 	currentBlock := self Label.
 	jump13 jmpTarget: currentBlock.
 	self MoveMw: 24 r: SPReg R: Extra3Reg.
-	self MoveR: Extra3Reg M64: 0 r: ClassReg.
-	self MoveR: ClassReg R: SendNumArgsReg.
+	self MoveR: Extra3Reg M64: 0 r: Extra2Reg.
+	self MoveR: Extra2Reg R: SendNumArgsReg.
 	self AddCq: 8 R: SendNumArgsReg.
-	self MoveR: SendNumArgsReg R: ClassReg.
+	self MoveR: SendNumArgsReg R: Extra2Reg.
 	jump13 := self Jump: b986.
 	currentBlock := self Label.
 	jump5 jmpTarget: currentBlock.
-	self MoveR: TempReg R: Extra2Reg.
+	self MoveR: ClassReg R: TempReg.
 	self MoveR: Extra1Reg R: SendNumArgsReg.
 	currentBlock := self Label.
 	jump6 jmpTarget: currentBlock.
 	self MoveMw: 32 r: SPReg R: Extra3Reg.
 	self MoveR: Extra3Reg R: Extra1Reg.
-	self MoveR: Extra2Reg R: SendNumArgsReg.
+	self MoveR: TempReg R: SendNumArgsReg.
 	self MoveR: SendNumArgsReg R: ClassReg.
 	currentBlock := self Label.
 	jump11 jmpTarget: currentBlock.
@@ -3547,7 +3524,8 @@ DruidTestRTLCompiler >> gen_pushLiteralConstantBytecode [
 		      ifNone: [ ^ self unknownBytecode ].
 	live := live bitOr: (self registerMaskFor: t0).
 	self genMoveConstant: methodObj R: t0.
-	self ssPushBase: t0 offset: 1 + LiteralStart << 3 + 8.
+	self ssPushConstant:
+		(coInterpreter int64AtPointer:  ((methodObj + 8) + ((1 + LiteralStart) << 3))).
 	^ 0
 ]
 
@@ -3555,63 +3533,56 @@ DruidTestRTLCompiler >> gen_pushLiteralConstantBytecode [
 DruidTestRTLCompiler >> gen_pushLiteralVariable16CasesBytecode [
 	"AutoGenerated by Druid"
 
-	| jump1 jumpNext b232 t1 jump3 currentBlock t0 jumpTrue jump2 t2 live |
+	| live currentBlock t0 |
 	live := 0.
 	t0 := self
 		      allocateRegNotConflictingWith: live
 		      ifNone: [ ^ self unknownBytecode ].
 	live := live bitOr: (self registerMaskFor: t0).
 	self genMoveConstant: methodObj R: t0.
-	self MoveM64: 0 + LiteralStart << 3 + 8 r: t0 R: t0.
-	t1 := self
-		      allocateRegNotConflictingWith: live
-		      ifNone: [ ^ self unknownBytecode ].
-	live := live bitOr: (self registerMaskFor: t1).
-	self MoveM64: 0 r: t0 R: t1.
-	self AndCq: 16r3FFFF7 R: t1.
-	self CmpCq: 0 R: t1.
-	jump1 := self JumpZero: 0.
-	self MoveR: t0 R: t1.
-	jump2 := self Jump: 0.
-	currentBlock := self Label.
-	jump1 jmpTarget: currentBlock.
-	self MoveM64: 8 r: t0 R: t1.
-	self MoveR: t1 R: t0.
-	b232 := self Label.
-	self MoveR: t0 R: t1.
-	self AndCq: 7 R: t1.
-	self CmpCq: 0 R: t1.
-	jump1 := self JumpNonZero: 0.
-	self MoveM64: 0 r: t0 R: t1.
-	self AndCq: 16r3FFFF7 R: t1.
-	t2 := self
-		      allocateRegNotConflictingWith: live
-		      ifNone: [ ^ self unknownBytecode ].
-	live := live bitOr: (self registerMaskFor: t2).
-	self MoveR: t1 R: t2.
-	self CmpCq: 0 R: t2.
-	jumpTrue := self JumpZero: 0.
-	self MoveCq: 0 R: t2.
-	jumpNext := self Jump: 0.
-	jumpTrue jmpTarget: self Label.
-	self MoveCq: 1 R: t2.
-	jumpNext jmpTarget: self Label.
-	self CmpCq: 0 R: t1.
-	jump3 := self JumpZero: 0.
-	currentBlock := self Label.
-	jump1 jmpTarget: currentBlock.
-	self MoveR: t0 R: t1.
-	currentBlock := self Label.
-	jump2 jmpTarget: currentBlock.
-	self ssPushBase: t1 offset: ValueIndex << 3 + 8.
-	jump2 := self Jump: 0.
-	currentBlock := self Label.
-	jump3 jmpTarget: currentBlock.
-	self MoveM64: 8 r: t0 R: t2.
-	self MoveR: t2 R: t0.
-	jump3 := self Jump: b232.
-	currentBlock := self Label.
-	jump2 jmpTarget: currentBlock.
+	0=((coInterpreter int64AtPointer:  (coInterpreter int64AtPointer:  ((methodObj + 8) + ((0 + LiteralStart) << 3)))) bitAnd: 4194295)
+		ifTrue: [
+			| jumpTrue jumpNext jump1 jump3 t1 jump2 b227 t2 |
+			self
+				MoveCq:
+				(coInterpreter int64AtPointer:  (((coInterpreter int64AtPointer:  ((methodObj + 8) + ((0 + LiteralStart) << 3))) + 8) + 0))
+				R: t0.
+			b227 := self Label.
+			t1 := self
+				      allocateRegNotConflictingWith: live
+				      ifNone: [ ^ self unknownBytecode ].
+			live := live bitOr: (self registerMaskFor: t1).
+			self MoveR: t0 R: t1.
+			self AndCq: 7 R: t1.
+			self CmpCq: 0 R: t1.
+			jump1 := self JumpNonZero: 0.
+			self MoveM64: 0 r: t0 R: t1.
+			self AndCq: 16r3FFFF7 R: t1.
+			t2 := self
+				      allocateRegNotConflictingWith: live
+				      ifNone: [ ^ self unknownBytecode ].
+			live := live bitOr: (self registerMaskFor: t2).
+			self MoveR: t1 R: t2.
+			self CmpCq: 0 R: t2.
+			jumpTrue := self JumpZero: 0.
+			self MoveCq: 0 R: t2.
+			jumpNext := self Jump: 0.
+			jumpTrue jmpTarget: self Label.
+			self MoveCq: 1 R: t2.
+			jumpNext jmpTarget: self Label.
+			self CmpCq: 0 R: t1.
+			jump2 := self JumpNonZero: 0.
+			self MoveM64: 8 r: t0 R: t2.
+			self MoveR: t2 R: t0.
+			jump3 := self Jump: b227.
+			currentBlock := self Label.
+			jump1 jmpTarget: currentBlock.
+			jump2 jmpTarget: currentBlock.
+			self ssPushConstant:
+				(coInterpreter int64AtPointer:  (((coInterpreter int64AtPointer:  ((methodObj + 8) + ((0 + LiteralStart) << 3))) + 8) + (ValueIndex << 3))).
+			^ 0 ].
+	self ssPushConstant:
+		(coInterpreter int64AtPointer:  (((coInterpreter int64AtPointer:  ((methodObj + 8) + ((0 + LiteralStart) << 3))) + 8) + (ValueIndex << 3))).
 	^ 0
 ]
 
@@ -3838,7 +3809,7 @@ DruidTestRTLCompiler >> gen_shortUnconditionalJump [
 DruidTestRTLCompiler >> gen_storeAndPopReceiverVariableBytecode [
 	"AutoGenerated by Druid"
 
-	| jump1 jump7 jumpNext t1 jump6 jump3 currentBlock t0 jump5 jump2 jumpTrue live t2 jump4 |
+	| jump1 jump7 jumpNext t1 jump6 jump3 currentBlock t0 jump5 jump2 jumpTrue jump8 live t2 jump4 |
 	live := 0.
 	self annotateBytecode: self Label.
 	self ensureReceiverResultRegContainsSelf.
@@ -3857,27 +3828,32 @@ DruidTestRTLCompiler >> gen_storeAndPopReceiverVariableBytecode [
 		      allocateRegNotConflictingWith: live
 		      ifNone: [ ^ self unknownBytecode ].
 	live := live bitOr: (self registerMaskFor: t2).
+	self MoveM64: 0 r: t0 R: t2.
+	self ArithmeticShiftRightCq: 23 R: t2.
+	self AndCq: 1 R: t2.
+	self CmpCq: 0 R: t2.
+	jump1 := self JumpNonZero: 0.
 	self MoveR: t0 R: t2.
 	self AndCq: 7 R: t2.
 	self ssFlushStack.
 	self CmpCq: 0 R: t2.
-	jump1 := self JumpNonZero: 0.
+	jump2 := self JumpNonZero: 0.
 	self MoveR: t0 R: t2.
 	self AndCq: objectMemory getMemoryMap getSpaceMaskToUse R: t2.
 	self CmpCq: objectMemory getMemoryMap getOldSpaceMask R: t2.
-	jump2 := self JumpNonZero: 0.
+	jump3 := self JumpNonZero: 0.
 	self MoveR: t1 R: t2.
 	self AndCq: 7 R: t2.
 	self CmpCq: 0 R: t2.
-	jump3 := self JumpNonZero: 0.
+	jump4 := self JumpNonZero: 0.
 	self MoveR: t1 R: t2.
 	self AndCq: objectMemory getMemoryMap getSpaceMaskToUse R: t2.
 	self CmpCq: objectMemory getMemoryMap getNewSpaceMask R: t2.
-	jump4 := self JumpZero: 0.
+	jump5 := self JumpZero: 0.
 	self MoveCq: 0 R: t2.
-	jump5 := self Jump: 0.
+	jump6 := self Jump: 0.
 	currentBlock := self Label.
-	jump4 jmpTarget: currentBlock.
+	jump5 jmpTarget: currentBlock.
 	self MoveR: t1 R: t2.
 	self CmpCq: objectMemory getMemoryMap getNewSpaceStart R: t2.
 	jumpTrue := self JumpGreaterOrEqual: 0.
@@ -3887,39 +3863,39 @@ DruidTestRTLCompiler >> gen_storeAndPopReceiverVariableBytecode [
 	self MoveCq: 1 R: t2.
 	jumpNext jmpTarget: self Label.
 	self CmpCq: 1 R: t2.
-	jump4 := self JumpZero: 0.
+	jump5 := self JumpZero: 0.
 	currentBlock := self Label.
-	jump5 jmpTarget: currentBlock.
-	jump5 := self Jump: 0.
+	jump6 jmpTarget: currentBlock.
+	jump6 := self Jump: 0.
 	currentBlock := self Label.
-	jump4 jmpTarget: currentBlock.
+	jump5 jmpTarget: currentBlock.
 	self MoveM64: 0 r: t0 R: t2.
 	self ArithmeticShiftRightCq: 29 R: t2.
 	self AndCq: 1 R: t2.
 	self CmpCq: 0 R: t2.
-	jump4 := self JumpNonZero: 0.
+	jump5 := self JumpNonZero: 0.
 	self MoveR: t0 R: TempReg.
 	backEnd saveAndRestoreLinkRegAround: [
 		self CallRT: ceStoreCheckTrampoline ].
 	self TstCq: 7 R: t1.
-	jump6 := self JumpNonZero: 0.
-	jump7 := self JumpZero: 0.
+	jump7 := self JumpNonZero: 0.
+	jump8 := self JumpZero: 0.
 	currentBlock := self Label.
-	jump1 jmpTarget: currentBlock.
 	jump2 jmpTarget: currentBlock.
 	jump3 jmpTarget: currentBlock.
-	jump5 jmpTarget: currentBlock.
 	jump4 jmpTarget: currentBlock.
+	jump6 jmpTarget: currentBlock.
+	jump5 jmpTarget: currentBlock.
 	self TstCq: 7 R: t1.
-	jump4 := self JumpNonZero: 0.
+	jump5 := self JumpNonZero: 0.
 	currentBlock := self Label.
-	jump7 jmpTarget: currentBlock.
+	jump8 jmpTarget: currentBlock.
 	self CmpCq: objectMemory nilObject R: t1.
-	jump7 := self JumpAboveOrEqual: 0.
+	jump8 := self JumpAboveOrEqual: 0.
 	self MoveCq: 0 R: t2.
-	jump5 := self Jump: 0.
+	jump6 := self Jump: 0.
 	currentBlock := self Label.
-	jump7 jmpTarget: currentBlock.
+	jump8 jmpTarget: currentBlock.
 	self MoveR: t1 R: t2.
 	self CmpCq: objectMemory trueObject R: t2.
 	jumpTrue := self JumpLessOrEqual: 0.
@@ -3929,24 +3905,24 @@ DruidTestRTLCompiler >> gen_storeAndPopReceiverVariableBytecode [
 	self MoveCq: 1 R: t2.
 	jumpNext jmpTarget: self Label.
 	currentBlock := self Label.
-	jump5 jmpTarget: currentBlock.
+	jump6 jmpTarget: currentBlock.
 	self CmpCq: 1 R: t2.
-	jump5 := self JumpZero: 0.
+	jump6 := self JumpZero: 0.
 	self CmpCq: objectMemory getMemoryMap getNewSpaceStart R: t1.
-	jump7 := self JumpLess: 0.
+	jump8 := self JumpLess: 0.
 	self MoveM64: 0 r: t0 R: t2.
 	self ArithmeticShiftRightCq: 29 R: t2.
 	self AndCq: 1 R: t2.
 	self CmpCq: 0 R: t2.
-	jump3 := self JumpNonZero: 0.
+	jump4 := self JumpNonZero: 0.
 	self MoveR: t0 R: t2.
 	self AndCq: 7 R: t2.
 	self CmpCq: 0 R: t2.
-	jump2 := self JumpZero: 0.
+	jump3 := self JumpZero: 0.
 	self MoveCq: 0 R: t2.
-	jump1 := self Jump: 0.
+	jump2 := self Jump: 0.
 	currentBlock := self Label.
-	jump2 jmpTarget: currentBlock.
+	jump3 jmpTarget: currentBlock.
 	self MoveR: t0 R: t2.
 	self AndCq: objectMemory getMemoryMap getSpaceMaskToUse R: t2.
 	self CmpCq: objectMemory getMemoryMap getPermSpaceMask R: t2.
@@ -3957,25 +3933,31 @@ DruidTestRTLCompiler >> gen_storeAndPopReceiverVariableBytecode [
 	self MoveCq: 1 R: t2.
 	jumpNext jmpTarget: self Label.
 	currentBlock := self Label.
-	jump1 jmpTarget: currentBlock.
+	jump2 jmpTarget: currentBlock.
 	self CmpCq: 1 R: t2.
-	jump1 := self JumpNonZero: 0.
+	jump2 := self JumpNonZero: 0.
 	self MoveR: t1 R: t2.
 	self AndCq: objectMemory getMemoryMap getSpaceMaskToUse R: t2.
 	self CmpCq: objectMemory getMemoryMap getPermSpaceMask R: t2.
-	jump2 := self JumpZero: 0.
+	jump3 := self JumpZero: 0.
 	self MoveR: t0 R: TempReg.
 	backEnd saveAndRestoreLinkRegAround: [
 		self CallRT: ceStoreCheckTrampoline ].
 	currentBlock := self Label.
+	jump7 jmpTarget: currentBlock.
+	jump5 jmpTarget: currentBlock.
 	jump6 jmpTarget: currentBlock.
+	jump8 jmpTarget: currentBlock.
 	jump4 jmpTarget: currentBlock.
-	jump5 jmpTarget: currentBlock.
-	jump7 jmpTarget: currentBlock.
-	jump3 jmpTarget: currentBlock.
-	jump1 jmpTarget: currentBlock.
 	jump2 jmpTarget: currentBlock.
+	jump3 jmpTarget: currentBlock.
 	self MoveR: t1 M64: 8 r: t0.
+	jump3 := self Jump: 0.
+	currentBlock := self Label.
+	jump1 jmpTarget: currentBlock.
+	self deoptimize.
+	currentBlock := self Label.
+	jump3 jmpTarget: currentBlock.
 	^ 0
 ]
 
diff --git a/Druid/DRBranchIfCondition.class.st b/Druid/DRBranchIfCondition.class.st
index a5f3b03c..10c5772d 100644
--- a/Druid/DRBranchIfCondition.class.st
+++ b/Druid/DRBranchIfCondition.class.st
@@ -30,7 +30,7 @@ DRBranchIfCondition >> beBackJumpTo: aDRBasicBlock [
 { #category : #accessing }
 DRBranchIfCondition >> beForwardJumpTo: aDRBasicBlock [
 
-	backJumps remove: aDRBasicBlock
+	backJumps remove: aDRBasicBlock ifAbsent: nil
 ]
 
 { #category : #accessing }
diff --git a/Druid/DRBytecodeIRGenerator.class.st b/Druid/DRBytecodeIRGenerator.class.st
index 41ee9014..822852a6 100644
--- a/Druid/DRBytecodeIRGenerator.class.st
+++ b/Druid/DRBytecodeIRGenerator.class.st
@@ -154,10 +154,14 @@ DRBytecodeIRGenerator >> interpretDirectSuperSendWith: aRBMessageNode [
 { #category : #'as yet unclassified' }
 DRBytecodeIRGenerator >> interpretDruidForceIntepretationWith: aRBMessageNode [
 
-	^ self
-		  addInstructionFrom: aRBMessageNode
-		  instructionKind: DRDeoptimize
-		  operands: #(  )
+	self
+		addInstructionFrom: aRBMessageNode
+		instructionKind: DRDeoptimize
+		operands: #(  ).
+
+	"Cut control flow"
+	self popOperand.
+	^ (RBReturnNode value: (RBLiteralNode value: 0)) acceptVisitor: self
 ]
 
 { #category : #'special-cases' }
@@ -512,10 +516,13 @@ DRBytecodeIRGenerator >> visitClassVariableNode: aRBVariableNode [
 
 	| value mappings |
 	value := aRBVariableNode variable name.
-	mappings := { 'FoxIFReceiver' -> 'FrameReceiverOffset' } asDictionary.
+	mappings := {
+		            ('FoxIFReceiver' -> 'FrameReceiverOffset').
+		            ('IMMUTABILITY' -> 'true') } asDictionary.
 	value := mappings at: value ifAbsent: [ value ].
 	^ self
 		  addInstructionFrom: aRBVariableNode
 		  instructionKind: DRCopy
-		  operands: { (DRConstantCompileTimeExpression new expression: value) }
+		  operands:
+		  { (DRConstantCompileTimeExpression new expression: value) }
 ]
diff --git a/Druid/DRCPSEdge.class.st b/Druid/DRCPSEdge.class.st
index 0fac4fe9..6a7cb169 100644
--- a/Druid/DRCPSEdge.class.st
+++ b/Druid/DRCPSEdge.class.st
@@ -133,10 +133,7 @@ DRCPSEdge >> operandDomainFromInstruction: aDRInstruction inBranch: branch [
 		| constraint |
 		constraint := self constraintFor: aDRInstruction result name.
 		^ constraint
-			  ifNil: [
-				  self
-					  operandDomainFromInstruction: aDRInstruction operand1
-					  inBranch: branch ]
+			  ifNil: [ branch condition acceptVisitor: self withBranch: branch ]
 			  ifNotNil: [
 			  DRRegisterDomain reg: aDRInstruction constraint: constraint ] ].
 
@@ -144,7 +141,9 @@ DRCPSEdge >> operandDomainFromInstruction: aDRInstruction inBranch: branch [
 		^ self operandDomainFromPhi: aDRInstruction ].
 
 	aDRInstruction isSetConditionCode ifTrue: [
-		^ aDRInstruction condition acceptVisitor: self withBranch: aDRInstruction ].
+		^ aDRInstruction condition
+			  acceptVisitor: self
+			  withBranch: aDRInstruction ].
 
 	^ nil
 ]
@@ -322,6 +321,12 @@ DRCPSEdge >> visitCopy: aDRCopy [
 	^ self addConstraint: constraint to: aDRCopy result name
 ]
 
+{ #category : #visiting }
+DRCPSEdge >> visitDeoptimize: aDRDeoptimize [
+
+	^ nil
+]
+
 { #category : #visiting }
 DRCPSEdge >> visitDivision: aDRDivision [ 
 
diff --git a/Druid/DRConstantValue.class.st b/Druid/DRConstantValue.class.st
index 036363b5..0b162aff 100644
--- a/Druid/DRConstantValue.class.st
+++ b/Druid/DRConstantValue.class.st
@@ -32,7 +32,6 @@ DRConstantValue >> acceptVisitor: aVisitor [
 { #category : #converting }
 DRConstantValue >> asJitCompileTimeExpression [
 
-1haltIf: [ self value asString = 'method' ].
 	^ DRConstantCompileTimeExpression expression: self value asString
 ]
 
diff --git a/Druid/DRControlFlowGraph.class.st b/Druid/DRControlFlowGraph.class.st
index 7837d1c5..bd6503fc 100644
--- a/Druid/DRControlFlowGraph.class.st
+++ b/Druid/DRControlFlowGraph.class.st
@@ -315,19 +315,16 @@ DRControlFlowGraph >> firstBasicBlock [
 { #category : #edges }
 DRControlFlowGraph >> fixBackJumps [
 
-	self blocks do: [ :block | 
-		block successors do: [ :succ | 
-			(block endInstruction isBackJumpTo: succ) ifTrue: [ "If back-jump to block a recursive phi should exist"
-				(succ endInstruction isBackJump or: [ 
-					 (succ phiFunctions anySatisfy: [ :phi | phi hasRecursiveUse ])
-						 not ]) ifTrue: [ "If not, then is a forward-jump" 
-					block endInstruction beForwardJumpTo: succ ] ] ].
-
-		block endInstruction isBackJump ifFalse: [ "Check if has a back-jump to this block"
-			(block phiFunctions anySatisfy: [ :phi | phi hasRecursiveUse ]) 
-				ifTrue: [ 
-					block backJumpPredecessors do: [ :pred | 
-						pred endInstruction beBackJumpTo: block ] ] ] ]
+	self buildDominatorTree.
+	self blocks do: [ :block |
+		| jump |
+		jump := block endInstruction.
+		block successors do: [ :succ |
+			| shouldBeBackjump |
+			shouldBeBackjump := block isDominatedBy: succ.
+			shouldBeBackjump
+				ifTrue: [ jump beBackJumpTo: succ ]
+				ifFalse: [ jump beForwardJumpTo: succ ] ] ]
 ]
 
 { #category : #edges }
diff --git a/Druid/DRFrameReturn.class.st b/Druid/DRFrameReturn.class.st
index 2127b5d7..b576f27b 100644
--- a/Druid/DRFrameReturn.class.st
+++ b/Druid/DRFrameReturn.class.st
@@ -4,8 +4,22 @@ Class {
 	#category : #'Druid-IR'
 }
 
+{ #category : #testing }
+DRFrameReturn >> isCopy [
+
+	^ self shouldKeepInCFG not
+]
+
 { #category : #testing }
 DRFrameReturn >> isFrameReturn [
 
 	^ true
 ]
+
+{ #category : #SCCP }
+DRFrameReturn >> sccpLatticeValueFor: sccp [
+
+	self shouldKeepInCFG ifTrue: [ ^ sccp bottom ].
+
+	^ super sccpLatticeValueFor: sccp
+]
diff --git a/Druid/DRIRGenerator.class.st b/Druid/DRIRGenerator.class.st
index 0cdfd375..eeaed77f 100644
--- a/Druid/DRIRGenerator.class.st
+++ b/Druid/DRIRGenerator.class.st
@@ -255,7 +255,8 @@ DRIRGenerator >> initializeSpecialCases [
 	specialCases at: #ifTrue: put: #interpretIfTrueWith:.
 	specialCases at: #whileTrue: put: #interpretWhileTrueWith:.
 	specialCases at: #caseOf:otherwise: put: #interpretCaseOfWith:.
-	
+	specialCases at: #cppIf:ifTrue: put: #interpretCppIfWith:.
+
 	specialCases at: #= put: #interpretEqualityComparisonWith:.
 	specialCases at: #~= put: #interpretInequalityComparisonWith:.
 	specialCases at: #< put: #interpretLessThanComparisonWith:.
@@ -737,6 +738,16 @@ DRIRGenerator >> interpretCondition: aRBMessageNode conditionKind: conditionKind
 				  operand2 }
 ]
 
+{ #category : #interpreting }
+DRIRGenerator >> interpretCppIfWith: aRBMessageNode [
+
+	| jitExpressionCopy |
+	jitExpressionCopy := self visitOperand: aRBMessageNode arguments first.
+	jitExpressionCopy simpleConstantFold expression = 'true' ifTrue: [
+		(RBMessageNode receiver: aRBMessageNode arguments second selector: #value)
+			acceptVisitor: self ]
+]
+
 { #category : #'special cases' }
 DRIRGenerator >> interpretDivisionWith: aRBMessageNode [ 
 
diff --git a/Druid/DRInstruction.class.st b/Druid/DRInstruction.class.st
index 61650413..c240e534 100644
--- a/Druid/DRInstruction.class.st
+++ b/Druid/DRInstruction.class.st
@@ -645,6 +645,8 @@ DRInstruction >> removeUser: anInstruction [
 { #category : #replacing }
 DRInstruction >> replaceBy: anotherInstruction [
 	
+	self = anotherInstruction ifTrue: [ ^ self ].
+	
 	basicBlock replace: self by: anotherInstruction.
 	
 	self replaceUsesBy: anotherInstruction.
@@ -871,17 +873,3 @@ DRInstruction >> veryDeepCopyWith: deepCopier [
 	deepCopier references at: origin ifAbsentPut: [nil].
 	^ super veryDeepCopyWith: deepCopier
 ]
-
-{ #category : #dependencies }
-DRInstruction >> withAllDependenciesExcept: alreadyComputedDependencies [
-	
-	| dependencies |
-	(alreadyComputedDependencies includes: self)
-		ifTrue: [ ^ alreadyComputedDependencies ].
-	
-	dependencies := OrderedCollection new.
-	dependencies add: self.
-	self dependencies do: [ :e |
-		dependencies addAll: e withAllDependencies ].
-	^ dependencies
-]
diff --git a/Druid/DRPhiFunction.class.st b/Druid/DRPhiFunction.class.st
index 96bbf90e..87eb3d13 100644
--- a/Druid/DRPhiFunction.class.st
+++ b/Druid/DRPhiFunction.class.st
@@ -45,7 +45,7 @@ DRPhiFunction >> addValue: anInstruction forPredecessor: aDRBasicBlock [
 	operands addLast: anInstruction
 ]
 
-{ #category : #accessing }
+{ #category : #'loop-invariance' }
 DRPhiFunction >> canMoveOutsideLoop: backJump [
 
 	^ false
@@ -68,7 +68,7 @@ DRPhiFunction >> hasRecursiveUse [
 	^ false
 ]
 
-{ #category : #accessing }
+{ #category : #testing }
 DRPhiFunction >> initialize [
 
 	super initialize.
@@ -190,7 +190,7 @@ DRPhiFunction >> rtlOperandQualifier [
 	^ 'R:'
 ]
 
-{ #category : #enumerating }
+{ #category : #SCCP }
 DRPhiFunction >> sccpLatticeValueFor: sccp [
 
 	^ sccp latticeValueOfPhiFunction: self
@@ -217,11 +217,11 @@ DRPhiFunction >> simpleConstantFold [
 	^ super simpleConstantFold
 ]
 
-{ #category : #simplification }
+{ #category : #transforming }
 DRPhiFunction >> simplify [
 
-	| simplifiedOperands worklist seen |
-	operands asSet size = 0 ifTrue: [ ^ DRNullValue new ].
+	| simplifiedOperands |
+	operands asSet isEmpty ifTrue: [ ^ DRNullValue new ].
 
 	"Use a worklist algorithm to iterate over the phi graph.
 	Ignore Phis and cut if we see a duplicated phi, this may happen in loops"
@@ -243,7 +243,7 @@ DRPhiFunction >> supportConstantOperand [
 	^ false
 ]
 
-{ #category : #simplification }
+{ #category : #types }
 DRPhiFunction >> type [
 
 	(self operands copyWithout: self) do: [ :o |
diff --git a/Druid/DRSCCP.class.st b/Druid/DRSCCP.class.st
index f3f47464..6f5edf1a 100644
--- a/Druid/DRSCCP.class.st
+++ b/Druid/DRSCCP.class.st
@@ -196,12 +196,14 @@ DRSCCP >> latticeValue: aValue [
 	^ latticeValues at: aValue ifAbsent: [ self top ]
 ]
 
-{ #category : #executing }
-DRSCCP >> latticeValueOfPhiFunction: operation [
+{ #category : #lattice }
+DRSCCP >> latticeValueOfPhiFunction: phiFunction [
 
 	| values |
+	"Recursive phi cannot determine the lattice (it is involved in a loop)"
+	phiFunction hasRecursiveUse ifTrue: [ ^ self bottom ].
 
-	values := operation operands collect: [ :e | 
+	values := phiFunction operands collect: [ :e | 
 		self latticeValue: e ] as: Set.
 	values remove: self top ifAbsent: [ "Nothing" ].
 	values size = 1 ifTrue: [ ^ values anyOne ].
@@ -335,7 +337,12 @@ DRSCCP >> tryReplaceInstructionByFoldedValue: i [
 	replacement := lattice result isNoResult
 		               ifTrue: [ lattice ]
 		               ifFalse: [
-		               DRCopy operands: { lattice asDRValue } result: i result ].
+			               i isCopy
+				               ifTrue: [ i "Take care of subclasses!" ]
+				               ifFalse: [
+				               DRCopy
+					               operands: { lattice asDRValue }
+					               result: i result ] ].
 
 	"We tell the lattice values that the new instruction has the same vlue as the old one"
 	latticeValues at: replacement put: (latticeValues at: i).
diff --git a/Druid/DRStrongCopy.class.st b/Druid/DRStrongCopy.class.st
index f136ffc4..59cc6686 100644
--- a/Druid/DRStrongCopy.class.st
+++ b/Druid/DRStrongCopy.class.st
@@ -4,26 +4,12 @@ Class {
 	#category : #'Druid-IR'
 }
 
-{ #category : #testing }
-DRStrongCopy >> isCopy [
-
-	^ self shouldKeepInCFG not
-]
-
 { #category : #testing }
 DRStrongCopy >> isMandatoryInstruction [
 
 	^ self shouldKeepInCFG
 ]
 
-{ #category : #SCCP }
-DRStrongCopy >> sccpLatticeValueFor: sccp [
-
-	self shouldKeepInCFG ifTrue: [ ^ sccp bottom ].
-
-	^ super sccpLatticeValueFor: sccp
-]
-
 { #category : #testing }
 DRStrongCopy >> shouldKeepInCFG [