VM Maker: VMMaker.oscog-eem.2009.mcz

 
Eliot Miranda uploaded a new version of VMMaker to project VM Maker:
http://source.squeak.org/VMMaker/VMMaker.oscog-eem.2009.mcz

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

Name: VMMaker.oscog-eem.2009
Author: eem
Time: 29 November 2016, 8:55:28.07135 am
UUID: c9c58171-fdba-44a6-82ad-292292746622
Ancestors: VMMaker.oscog-eem.2008

RegisterAllocatingCogit:
Fix liveRegisters to scan entire stack, not just from spillBase.
Add intelligence to genStorePop:TemporaryVariable: to avoid writing through a register.

=============== Diff against VMMaker.oscog-eem.2008 ===============

Item was changed:
  ----- Method: RegisterAllocatingCogit>>genStorePop:TemporaryVariable: (in category 'bytecode generator support') -----
  genStorePop: popBoolean TemporaryVariable: tempIndex
  <inline: false>
+ | srcRegOrNone destReg |
- | reg |
  self ssFlushUpThroughTemporaryVariable: tempIndex.
+ "To avoid a stall writing through destReg, remember srcReg before the potential ssPop: 1 in ssStorePop:toReg:"
+ srcRegOrNone := self ssTop registerOrNone.
  "ssStorePop:toPreferredReg: will allocate a register, and indeed may allocate ReceiverResultReg
  if, for example, the ssEntry to be popped is already in ReceiverResultReg (as the result of a send).
  ReceiverResultReg is not a good choice for a temporary variable; it has other uses.  So if the ssEntry
  at top of stack has ReceiverResultReg as its live variable, try and allocate an alternative."
  ((self ssTop registerMaskOrNone anyMask: self registerMaskUndesirableForTempVars)
+ and: [(destReg := self availableRegOrNoneNotConflictingWith: (self registerMaskUndesirableForTempVars bitOr: self liveRegisters)) ~= NoReg])
+ ifTrue: [self ssStorePop: popBoolean toReg: destReg]
+ ifFalse: [destReg := self ssStorePop: popBoolean toPreferredReg: TempReg].
+ self MoveR: (srcRegOrNone ~= NoReg ifTrue: [srcRegOrNone] ifFalse: [destReg])
- and: [(reg := self availableRegOrNoneNotConflictingWith:  self registerMaskUndesirableForTempVars) ~= NoReg])
- ifTrue: [self ssStorePop: popBoolean toReg: reg]
- ifFalse: [reg := self ssStorePop: popBoolean toPreferredReg: TempReg].
- self MoveR: reg
  Mw: (self frameOffsetOfTemporary: tempIndex)
  r: FPReg.
+ destReg ~= TempReg ifTrue:
+ [(self simStackAt: tempIndex) liveRegister: destReg.
- reg ~= TempReg ifTrue:
- [(self simStackAt: tempIndex) liveRegister: reg.
  self copyLiveRegisterToCopiesOf: (self simStackAt: tempIndex)].
  ^0!

Item was added:
+ ----- Method: RegisterAllocatingCogit>>liveRegisters (in category 'simulation stack') -----
+ liveRegisters
+ | regsSet |
+ regsSet := 0.
+ 0 to: simStackPtr do:
+ [:i|
+ regsSet := regsSet bitOr: (self simStackAt: i) registerMask].
+ LowcodeVM ifTrue:
+ [(simNativeSpillBase max: 0) to: simNativeStackPtr do:
+ [:i|
+ regsSet := regsSet bitOr: (self simNativeStackAt: i) nativeRegisterMask]].
+ ^regsSet!