The Trunk: Compiler-eem.376.mcz

Eliot Miranda uploaded a new version of Compiler to project The Trunk:
http://source.squeak.org/trunk/Compiler-eem.376.mcz

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

Name: Compiler-eem.376
Author: eem
Time: 14 March 2018, 1:07:25.770492 pm
UUID: 5a1a43dc-5467-4e83-86f3-d6ba1cba0765
Ancestors: Compiler-eem.375

Fix some bugs in the new machinery thown up by tests for false positives.

=============== Diff against Compiler-eem.375 ===============

Item was changed:
  ----- Method: EncoderForSistaV1 class>>scanBlockOrNilForLiteral: (in category 'scanning') -----
  scanBlockOrNilForLiteral: aLiteral
  "Answer a block argument for CompiledMethod>>#scanFor: that answers
  if the method refers to the literal implicitly via a special bytecode.
  If the literal is not accessible via a special bytecode, answer nil."
+ | value hi lo unextended |
+
- | value hi lo |
  "96-111 0110 iiii Send Arithmetic Message #iiii (+ - < > <= >= = ~= * / \\ @ bitShift: // bitAnd: bitOr:)
  112-119 01110 iii Send Special Message #iii + 0 (at: at:put: size next nextPut: atEnd == class)"
  aLiteral isSymbol ifTrue:
  [value := 96 + ((Smalltalk specialSelectors indexOf: aLiteral ifAbsent: [^nil]) // 2).
  ^[:byte| byte = value]].
+
+ "80 01010000 Push 0
+ 81 01010001 Push 1
+ 232 11101000 iiiiiiii Push Integer #iiiiiiii (+ Extend B * 256, where bbbbbbbb = sddddddd, e.g. -32768 = i=0, d=0, s=1)"
- "232 11101000 iiiiiiii Push Integer #iiiiiiii (+ Extend B * 256, where bbbbbbbb = sddddddd, e.g. -32768 = i=0, d=0, s=1)"
  aLiteral isInteger ifTrue:
+ [aLiteral >= 0 ifTrue:
+ [aLiteral <= 1 ifTrue:
+ [value := aLiteral + 80.
+ ^[:byte| byte = value]].
+ aLiteral <= 255 ifTrue:
+ [unextended := true. "Don't be fooled by extended cases with the same least significant byte!!"
+ ^[:b1 :b2| | found |
+ found := b1 = 232 and: [b2 = aLiteral and: [unextended]].
+ unextended := b1 ~= 16rE1.
+ found]]].
+ (aLiteral between: -32768 and: 32767) ifFalse: [^nil].
- [(aLiteral between: -32768 and: 32767) ifFalse: [^nil].
- (aLiteral between: 0 and: 255) ifTrue:
- [^[:b1 :b2| b1 = 232 and: [b2 = aLiteral]]].
  lo := aLiteral bitAnd: 255.
  hi := (aLiteral bitShift: -8) bitAnd: 255.
  ^[:b1 :b2 :b3 :b4| b1 = 16rE1 and: [b2 = hi and: [b3 = 232 and: [b4 = lo]]]]].
+
  "233 11101001 iiiiiiii Push Character #iiiiiiii (+ Extend B * 256)"
  aLiteral isCharacter ifTrue:
+ [(value := aLiteral asInteger) <= 255 ifTrue:
+ [unextended := true. "Don't be fooled by extended cases with the same least significant byte!!"
+ ^[:b1 :b2| | found |
+ found := b1 = 233 and: [b2 = value and: [unextended]].
+ unextended := b1 ~= 16rE1.
+ found]].
+ ^value <= 65535 ifTrue:
+ [lo := value bitAnd: 255.
+ hi := (value bitShift: -8) bitAnd: 255.
+ [:b1 :b2 :b3 :b4| b1 = 16rE1 and: [b2 = hi and: [b3 = 233 and: [b4 = lo]]]]]].
- [((value := aLiteral asInteger) > 65535) ifTrue: [^nil].
- (aLiteral between: 0 and: 255) ifTrue:
- [^[:b1 :b2| b1 = 233 and: [b2 = value]]].
- lo := value bitAnd: 255.
- hi := (value bitShift: -8) bitAnd: 255.
- ^[:b1 :b2 :b3 :b4| b1 = 16rE1 and: [b2 = hi and: [b3 = 233 and: [b4 = lo]]]]].
 
  "77 01001101 Push true
  78 01001110 Push false
  79 01001111 Push nil
  88-91 010110 ii Return Receiver/true/false/nil
  93 01011101 BlockReturn nil"
  aLiteral == true ifTrue:
  [^[:byte| byte = 77 or: [byte = 89]]].
  aLiteral == false ifTrue:
  [^[:byte| byte = 78 or: [byte = 90]]].
  aLiteral == nil ifTrue:
  [^[:byte| byte = 79 or: [byte = 91 or: [byte = 93]]]].
  ^nil!

Item was changed:
  ----- Method: EncoderForV3 class>>scanBlockOrNilForLiteral: (in category 'scanning') -----
  scanBlockOrNilForLiteral: aLiteral
  "Answer a block argument for CompiledMethod>>#scanFor: that answers
  if the method refers to the literal implicitly via a special bytecode.
  If the literal is not accessible via a special bytecode, answer nil."
  | value |
  "176-191 1011iiii Send Arithmetic Message #iiii
  192-207 1100iiii Send Special Message #iiii"
  (aLiteral isSymbol or: [aLiteral isInteger]) ifTrue:
  [value := aLiteral isSymbol
  ifTrue: [176 + ((Smalltalk specialSelectors indexOf: aLiteral ifAbsent: [^nil]) // 2)]
  ifFalse: [(aLiteral between: -1 and: 2) ifFalse: [^nil].
  aLiteral + 117].
  ^[:byte| byte = value]].
  "112-119 01110iii Push (receiver, true, false, nil, -1, 0, 1, 2) [iii]
  120-123 011110ii Return (receiver, true, false, nil) [ii] From Message"
- aLiteral == nil ifTrue:
- [^[:byte| byte = 115 or: [byte = 123]]].
  aLiteral == true ifTrue:
+ [^[:byte| byte = 113 or: [byte = 121]]].
- [^[:byte| byte = 116 or: [byte = 124]]].
  aLiteral == false ifTrue:
+ [^[:byte| byte = 114 or: [byte = 122]]].
+ aLiteral == nil ifTrue:
+ [^[:byte| byte = 115 or: [byte = 123]]].
- [^[:byte| byte = 117 or: [byte = 125]]].
  ^nil!