[Vm-dev] VM Maker: VMMaker.oscog-eem.2063.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.2063.mcz

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

Name: VMMaker.oscog-eem.2063
Author: eem
Time: 31 December 2016, 2:37:08.922183 pm
UUID: 034eff8c-70b0-4106-b87e-a02a6a9aa506
Ancestors: VMMaker.oscog-eem.2062

SmartSyntaxPlugin Slang:

Avoid generating unreachable code when failing.  Avoid an unnecessary test for failed if returning an expression which can't fail.  Nuke an unused method.

=============== Diff against VMMaker.oscog-eem.2062 ===============

Item was removed:
- ----- Method: SmartSyntaxPluginTMethod>>checkSuccessExpr (in category 'private') -----
- checkSuccessExpr
- 	"Return the parse tree for an expression that aborts the primitive if the successFlag is not true."
- 
- 	| expr |
- 	expr := 'interpreterProxy failed ifTrue: [^nil]'.
- 	^ self statementsFor: expr varName: ''
- !

Item was changed:
  ----- Method: SmartSyntaxPluginTMethod>>fixUpReturnOneStmt:on: (in category 'transforming') -----
  fixUpReturnOneStmt: stmt on: sStream
  
  	stmt isReturn ifFalse: [^sStream nextPut: stmt].
  	(stmt expression isSend
  	 and: [#('primitiveFail' 'primitiveFailFor:') includes: stmt expression selector]) ifTrue: 
  		["failure return"
  		 sStream nextPut: stmt expression.
  		 sStream nextPut: self nullReturnExpr.
  		 ^nil].
  	(stmt expression isVariable and: ['nil' = stmt expression name]) ifTrue: 
  		["^ nil -- this is never right unless automatically generated"
  		 sStream nextPut: stmt.
  		 ^nil].
  	(stmt expression isVariable and: ['self' = stmt expression name]) ifTrue: 
  		["^ self"
  		 self generateFailureGuardOn: sStream.
  		 fullArgs isEmpty ifFalse:[ sStream nextPut: (self popExpr: fullArgs size)].
  		 sStream nextPut: self nullReturnExpr.
  		 ^nil].
  	(stmt expression isVariable | stmt expression isConstant | suppressingFailureGuards) ifTrue:
  		["^ variable or ^ constant or ^ expr without guardchecking"
  		 self generateFailureGuardOn: sStream.
  		 sStream nextPut: (self pop: fullArgs size + 1 thenReturnExpr: stmt expression).
  		 sStream nextPut: self nullReturnExpr.
  		 ^nil].
+ 	"^ expr with necessary guard checking"
- 	"^ expr with guardchecking"
  	self generateFailureGuardOn: sStream.
+ 	(self resultExpressionAlwaysFails: stmt expression)
+ 		ifTrue:
+ 			[sStream nextPut: stmt expression]
+ 		ifFalse:
+ 			[sStream nextPut: (self assign: (self oopVariable: '_return_value') expression: stmt expression).
+ 			 (self resultExpressionCanFail: stmt expression) ifTrue:
+ 				[self generateFailureGuardOn: sStream].
+ 			 sStream nextPut: (self pop: fullArgs size + 1 thenReturnExpr: (self oopVariable: '_return_value'))].
+ 	sStream nextPut: self nullReturnExpr!
- 	sStream nextPut: (self assign: (self oopVariable: '_return_value') expression: stmt expression).
- 	self generateFailureGuardOn: sStream.
- 	sStream nextPut: (self pop: fullArgs size + 1 thenReturnExpr: (self oopVariable: '_return_value')).
- 	sStream nextPut: self nullReturnExpr
- !

Item was removed:
- ----- Method: SmartSyntaxPluginTMethod>>oldReplaceSizeMessages (in category 'private') -----
- oldReplaceSizeMessages
- 	"Replace sends of the message 'size' with calls to sizeOfSTArrayFromCPrimitive."
- 
- 	| argExpr |
- 	parseTree nodesDo: [:n |
- 		(n isSend and: [n selector = #size]) ifTrue: [
- 			argExpr := TSendNode new
- 				setSelector: #+
- 				receiver: n receiver
- 				arguments: (Array with: (TConstantNode new setValue: 1)).
- 			n
- 				setSelector: #sizeOfSTArrayFromCPrimitive:
- 				receiver: (TVariableNode new setName: 'interpreterProxy')
- 				arguments: (Array with: argExpr)]].
- !

Item was added:
+ ----- Method: SmartSyntaxPluginTMethod>>resultExpressionAlwaysFails: (in category 'private') -----
+ resultExpressionAlwaysFails: aTSendNode
+ 	^aTSendNode selector == #success:
+ 	 and: [aTSendNode args first isConstant
+ 	 and: [aTSendNode args first value == false]]!

Item was added:
+ ----- Method: SmartSyntaxPluginTMethod>>resultExpressionCanFail: (in category 'private') -----
+ resultExpressionCanFail: aTSendNode
+ 	"Neither asSmallIntegerObj nor asBooleanObj can fail."
+ 	^(#(asSmallIntegerObj asBooleanObj) includes: aTSendNode selector) not!