The Trunk: Compiler-nice.430.mcz

Nicolas Cellier uploaded a new version of Compiler to project The Trunk:
http://source.squeak.org/trunk/Compiler-nice.430.mcz

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

Name: Compiler-nice.430
Author: nice
Time: 10 May 2020, 9:27:14.242821 am
UUID: 7ba9b09a-1ebd-4181-bf85-2dc912f42c9d
Ancestors: Compiler-nice.429

Fixup: caseError must be sent to the receiver of the caseOf: message, not to the receiver of the home method.

For this, we must also dup/pop in the last case whenever there is no otherwise argument.

See http://forum.world.st/Problems-with-caseError-tp5111930p5112255.html

TODO: also fix the Decompiler...

=============== Diff against Compiler-nice.429 ===============

Item was changed:
  ----- Method: MessageNode>>emitCodeForCase:encoder:value: (in category 'code generation') -----
  emitCodeForCase: stack encoder: encoder value: forValue
 
  | braceNode sizeStream allReturn |
  forValue ifFalse:
  [^super emitCodeForEffect: stack encoder: encoder].
  braceNode := arguments first.
  sizeStream := ReadStream on: sizes.
  receiver emitCodeForValue: stack encoder: encoder.
  "There must be at least one branch around the otherwise/caseError
   so the decompiler can identify the end of the otherwise/caseError."
  allReturn := true. "assume every case ends with a return"
  braceNode casesForwardDo:
+ [:keyNode :valueNode :last |
+ | thenSize elseSize dropReceiver |
+ dropReceiver := last and: [arguments size >= 2].
- [:keyNode :valueNode :last | | thenSize elseSize |
  thenSize := sizeStream next.
  elseSize := sizeStream next.
+ dropReceiver ifFalse: [encoder genDup. stack push: 1].
- last ifFalse: [encoder genDup. stack push: 1].
  keyNode emitCodeForEvaluatedValue: stack encoder: encoder.
  keyNode pc: encoder nextPC.
  equalNode emitCode: stack args: 1 encoder: encoder.
  self emitCodeForBranchOn: false dist: thenSize pop: stack encoder: encoder.
+ dropReceiver ifFalse: [encoder genPop. stack pop: 1].
- last ifFalse: [encoder genPop. stack pop: 1].
  valueNode emitCodeForEvaluatedValue: stack encoder: encoder.
+ dropReceiver ifTrue: [stack pop: 1].
- last ifTrue: [stack pop: 1].
  valueNode returns ifFalse:
  [self emitCodeForJump: elseSize encoder: encoder.
  allReturn := false].
  (last and: [allReturn]) ifTrue:
  [self emitCodeForJump: elseSize encoder: encoder]].
  arguments size = 2
  ifTrue:
  [arguments last emitCodeForEvaluatedValue: stack encoder: encoder] "otherwise: [...]"
  ifFalse:
+ ["the receiver of caseOf: has been previously dup, just send"
- [NodeSelf emitCodeForValue: stack encoder: encoder.
  caseErrorNode emitCode: stack args: 0 encoder: encoder]!

Item was changed:
  ----- Method: MessageNode>>sizeCodeForCase:value: (in category 'code generation') -----
  sizeCodeForCase: encoder value: forValue
 
  | braceNode sizeIndex elseSize allReturn |
  forValue not ifTrue:
  [^super sizeCodeForEffect: encoder].
  equalNode := encoder encodeSelector: #=.
  braceNode := arguments first.
  sizes := Array new: 2 * braceNode numElements.
  sizeIndex := sizes size.
  elseSize := arguments size = 2
  ifTrue:
  [arguments last sizeCodeForEvaluatedValue: encoder] "otherwise: [...]"
  ifFalse:
  [caseErrorNode := encoder encodeSelector: #caseError.
+ "Assume that the receiver of caseOf: has been dup"
+ (caseErrorNode sizeCode: encoder args: 0 super: false)]. "self caseError"
- (NodeSelf sizeCodeForValue: encoder)
- + (caseErrorNode sizeCode: encoder args: 0 super: false)]. "self caseError"
  "There must be at least one branch around the otherwise/caseError
   so the decompiler can identify the end of the otherwise/caseError."
  allReturn := true. "assume every case ends with a return"
  braceNode casesForwardDo:
  [:keyNode :valueNode :last |
  valueNode returns ifFalse: [allReturn := false]].
  braceNode casesReverseDo:
+ [:keyNode :valueNode :last |
+ | thenSize dropReceiver |
+ dropReceiver := last and: [arguments size >= 2].
- [:keyNode :valueNode :last | | thenSize |
  sizes at: sizeIndex put: elseSize.
  thenSize := valueNode sizeCodeForEvaluatedValue: encoder.
+ dropReceiver ifFalse: [thenSize := thenSize + encoder sizePop].
- last ifFalse: [thenSize := thenSize + encoder sizePop].
  valueNode returns ifFalse: [thenSize := thenSize + (self sizeCode: encoder forJump: elseSize)].
  (last and: [allReturn]) ifTrue: [thenSize := thenSize + (self sizeCode: encoder forJump: elseSize)].
  sizes at: sizeIndex-1 put: thenSize.
+ dropReceiver ifFalse: [elseSize := elseSize + encoder sizeDup].
- last ifFalse: [elseSize := elseSize + encoder sizeDup].
  elseSize := elseSize
  + (keyNode sizeCodeForEvaluatedValue: encoder)
  + (equalNode sizeCode: encoder args: 1 super: false)
  + (self sizeCode: encoder forBranchOn: false dist: thenSize)
  + thenSize.
  sizeIndex := sizeIndex - 2].
  ^(receiver sizeCodeForValue: encoder) + elseSize!