[Vm-dev] VM Maker: VMMaker.oscog-eem.1312.mcz

[commits at source.squeak.org]

Eliot Miranda uploaded a new version of VMMaker to project VM Maker:
http://source.squeak.org/VMMaker/VMMaker.oscog-eem.1312.mcz

==================== Summary ====================

Name: VMMaker.oscog-eem.1312
Author: eem
Time: 17 May 2015, 5:41:05.845 pm
UUID: f2ba142e-f4e1-43de-9f3e-b33fa10e5e45
Ancestors: VMMaker.oscog-eem.1311

Make accessor depth calculation more accurate by
not considering fetchInteger:ofObject: and arraySize:
et al as object accessors.

Make the read-before-written initializer safer, only
initialzing simple types (integers and pointers).

Be prepared to answer the size of usqInt.

=============== Diff against VMMaker.oscog-eem.1311 ===============

Item was changed:
  ----- Method: CCodeGenerator>>accessorDepthForChain: (in category 'spur primitive compilation') -----
  accessorDepthForChain: chain "OrderedCollection"
  	"Answer the actual number of accessors in the access chain, filtering out assignments of variables to variables."
  	| accessorDepth |
  	accessorDepth := 0.
  	chain do:
  		[:node|
+ 		 ((node isAssignment and: [node expression isVariable])
+ 		  or: [node isSend and: [SpurMemoryManager isSameLevelObjectAccessor: node selector]]) ifFalse:
- 		 (node isAssignment and: [node expression isVariable]) ifFalse:
  			[accessorDepth := accessorDepth + 1]].
  	^accessorDepth!

Item was changed:
  ----- Method: CCodeGenerator>>accessorsAndAssignmentsForMethod:actuals:depth:interpreterClass:into: (in category 'spur primitive compilation') -----
  accessorsAndAssignmentsForMethod: method actuals: actualParameters depth: depth interpreterClass: interpreterClass into: aTrinaryBlock
  	"Evaluate aTrinaryBlock with the root accessor sends, accessor sends and assignments in the method."
  	| accessors assignments roots |
  	accessors := Set new.
  	assignments := Set new.
  	roots := Set new.
  	actualParameters with: method args do:
  		[:actual :argName|
  		 (actual isVariable or: [actual isSend]) ifTrue:
  			[(actual isSend and: [self isStackAccessor: actual selector given: interpreterClass]) ifTrue:
  				[roots add: actual].
  			assignments add: (TAssignmentNode new
  									setVariable: (TVariableNode new setName: argName)
  									expression: actual)]].
  	method parseTree nodesDo:
  		[:node|
  		node isSend ifTrue:
  			[(self isStackAccessor: node selector given: interpreterClass) ifTrue:
  				[roots add: node].
  			 (self isObjectAccessor: node selector given: interpreterClass) ifTrue:
  				[accessors add: node].
  			 (self accessorDepthDeterminationFollowsSelfSends
  			  and: [node receiver isVariable
  			  and: [node receiver name = 'self'
  			  and: [roots isEmpty
  				or: [node args anySatisfy:
  					[:arg|
  					 (roots includes: arg)
  					 or: [(accessors includes: arg)
  					 or: [assignments anySatisfy: [:assignment| assignment variable isSameAs: arg]]]]]]]]) ifTrue:
  				[self accessorsAndAssignmentsForSubMethodNamed: node selector
  					actuals: node args
  					depth: depth + 1
  					interpreterClass: interpreterClass
  					into: [:subRoots :subAccessors :subAssignments|
  						(subRoots isEmpty and: [subAccessors isEmpty and: [subAssignments isEmpty]]) ifFalse:
  							[roots addAll: subRoots.
  							 accessors add: node.
  							 accessors addAll: subAccessors.
  							 assignments addAll: subAssignments]]]].
  		(node isAssignment
+ 		 and: [(node expression isSend and: [SpurMemoryManager isTerminalObjectAccessor: node expression selector]) not
  		 and: [(roots includes: node expression)
  			or: [(accessors includes: node expression)
+ 			or: [node expression isVariable and: [node expression name ~= 'nil']]]]]) ifTrue:
- 			or: [node expression isVariable and: [node expression name ~= 'nil']]]]) ifTrue:
  			[assignments add: node]].
  	^aTrinaryBlock
  		value: roots
  		value: accessors
  		value: assignments!

Item was added:
+ ----- Method: CCodeGenerator>>isSimpleType: (in category 'type inference') -----
+ isSimpleType: aType
+ 	"For the purposes of the read-before-written initializer, answer if
+ 	 aType is simple, e.g. not a structure, and array or an opaque type."
+ 	^aType last = $*
+ 	  or: [#(	sqInt usqInt sqLong usqLong
+ 			int #'unsigned int' double float
+ 			short #'unsigned short'
+ 			char #'unsigned char' #'signed char') includes: aType]!

Item was added:
+ ----- Method: SpurMemoryManager class>>isSameLevelObjectAccessor: (in category 'translation') -----
+ isSameLevelObjectAccessor: selector
+ 	"For accessor depth calculation, answer if selector doesn't traverse into an object, merely deriving a pointer from it."
+ 	^#(arrayValueOf: firstFixedField: firstIndexableField:) includes: selector!

Item was added:
+ ----- Method: SpurMemoryManager class>>isTerminalObjectAccessor: (in category 'translation') -----
+ isTerminalObjectAccessor: selector
+ 	"For accessor depth calculation, answer if selector doesn't answer another object object; merely a value."
+ 	^#(byteSizeOf: fetchFloat:ofObject: fetchInteger:ofObject: fetchLong32:ofObject: instanceSizeOf: slotSizeOf: stSizeOf:) includes: selector!

Item was changed:
  ----- Method: TMethod>>removeUnusedTempsAndNilIfRequiredIn: (in category 'utilities') -----
  removeUnusedTempsAndNilIfRequiredIn: aCodeGen
  	"Remove all of the unused temps in this method. Answer a set of the references.
  	 As a side-effect introduce explicit temp := nil statements for temps that are
  	 tested for nil before necessarily being assigned."
  	| refs readBeforeAssigned |
  	refs := self removeUnusedTempsIn: aCodeGen.
  	"reset the locals to be only those still referred to"
  	locals := locals select: [:e| refs includes: e].
  	(locals notEmpty
  	 and: [aCodeGen
  			pushScope: declarations
+ 			while: [(readBeforeAssigned := (self findReadBeforeAssignedIn: (locals select: [:ea| aCodeGen isSimpleType: (self typeFor: ea in: aCodeGen)])
+ 												in: aCodeGen)) notEmpty]]) ifTrue:
- 			while: [(readBeforeAssigned := (self findReadBeforeAssignedIn: locals in: aCodeGen)) notEmpty]]) ifTrue:
  		[readBeforeAssigned := readBeforeAssigned reject:
  			[:v| | d | "don't initialize externs, arrays or the explicitly initialized."
  			 d := self declarationAt: v.
  			 (d beginsWith: 'extern') or: [(d includes: $[) or: [d includes: $=]]].
  		 parseTree statements addAllFirst:
  			(readBeforeAssigned asSortedCollection collect:
  				[:var|
  				TAssignmentNode new
  					setVariable: (TVariableNode new setName: var; yourself)
  					expression: (TConstantNode new setValue: 0; yourself)])].
  	^refs!

Item was changed:
  ----- Method: VMClass>>sizeof: (in category 'translation support') -----
  sizeof: objectSymbolOrClass
  	<doNotGenerate>
  	| index |
  	objectSymbolOrClass isInteger ifTrue:
  		[^self class objectMemoryClass wordSize].
  	objectSymbolOrClass isSymbol ifTrue:
  		[(objectSymbolOrClass last == $*
  		 or: [#long == objectSymbolOrClass
  		 or: [#'unsigned long' == objectSymbolOrClass]]) ifTrue:
  			[^self class objectMemoryClass wordSize].
  		index := #(	#sqLong #usqLong #double
  					#int #'unsigned int' #float
  					#short #'unsigned short'
  					#char #'unsigned char' #'signed char')
  						indexOf: objectSymbolOrClass
  						ifAbsent:
+ 							[(#(usqInt sqInt) includes: objectSymbolOrClass) ifTrue: [^self class objectMemoryClass bytesPerOop].
- 							[objectSymbolOrClass = #sqInt ifTrue: [^self class objectMemoryClass bytesPerOop].
  							 self error: 'unrecognized C type name'].
  		^#(8 8 8
  			4 4 4
  			2 2
  			1 1 1) at: index].
  	^(objectSymbolOrClass isBehavior
  		ifTrue: [objectSymbolOrClass]
  		ifFalse: [objectSymbolOrClass class])
  			alignedByteSizeOf: objectSymbolOrClass
  			forClient: self!