[Vm-dev] VM Maker: BytecodeSets.spur-eem.70.mcz

commits at source.squeak.org commits at source.squeak.org
Sat Jan 21 00:20:54 UTC 2017


Eliot Miranda uploaded a new version of BytecodeSets to project VM Maker:
http://source.squeak.org/VMMaker/BytecodeSets.spur-eem.70.mcz

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

Name: BytecodeSets.spur-eem.70
Author: eem
Time: 20 January 2017, 4:20:42.691217 pm
UUID: a4a9ce55-201c-4024-aae7-5c2c3d3ffe72
Ancestors: BytecodeSets.spur-eem.69

interpretNext3ByteSistaV1Instruction:for:extA:extB:startPC: must decode the literal for the branchIf[Not]InstanceOf:distance: bytecode.

=============== Diff against BytecodeSets.spur-eem.69 ===============

Item was changed:
  ----- Method: InstructionStream>>interpretNext3ByteSistaV1Instruction:for:extA:extB:startPC: (in category '*BytecodeSets-SistaV1-decoding') -----
  interpretNext3ByteSistaV1Instruction: bytecode for: client extA: extA extB: extB startPC: startPC
  	"Send to the argument, client, a message that specifies the next instruction.
  	 This method handles the three-byte codes.
  	 For a table of the bytecode set, see EncoderForSistaV1's class comment."
  
  	| method byte2 byte3 literal |
  	method := self method.
  	byte2 := method at: pc.
  	byte3 := method at: pc + 1.
  	pc := pc + 2.
  
  	"**	248	(2)	11111000 	iiiiiiii		mssjjjjj		Call Primitive #iiiiiiii + (jjjjj * 256) 
  									m=1 means inlined primitive, no hard return after execution. 
  									ss defines the unsafe operation set used to encode the operations. 
  									(ss = 0 means sista unsafe operations, ss = 01 means lowcode operations, other numbers are not used)
  									Lowcode inlined primitives may have extensions."
  	bytecode = 248 ifTrue:
  		[| primitiveSetSelector primitiveNumber |
  		 byte3 < 128 ifTrue:
  			[ "Maybe this should be restricted to the 13 bit primitiveNumber too..."
  			 ^client callPrimitive: byte2 + (byte3 bitShift: 8)].
  		 primitiveSetSelector := (byte3 bitShift: -5) bitAnd: 3.
  		 primitiveNumber := byte2 + ((byte3 bitAnd: 31) bitShift: 8).
  		 primitiveSetSelector = 0 ifTrue: "Sista inline primitives"
  			[^client callInlinePrimitive: byte2 + (byte3 - 128 bitShift: 8)].
  		 primitiveSetSelector = 1 ifTrue: "Lowcode inline primitives"
  			[^client callLowcodeInlinePrimitive: byte2 + (byte3 - 128 bitShift: 8) extA: extA extB: extB].
  		 "fall through to ^self unusedBytecode: client at: startPC below"].
  
  	"*	249		11111001	xxxxxxxx	siyyyyyy	push Closure Compiled block literal index xxxxxxxx (+ Extend A * 256) numCopied yyyyyy receiverOnStack: s = 1 ignoreOuterContext: i = 1"
  	bytecode = 249 ifTrue:
  		[literal := method literalAt: (extA bitShift: 8) + byte2 + 1.
  		 ^client pushFullClosure: literal numCopied: (byte3 bitAnd: 16r3F)].
  	bytecode = 250 ifTrue:
  		["**	250  11111010  eeiiikkk  jjjjjjjj  Push Closure Num Copied iii (+ExtA//16*8) Num Args kkk (+ ExtA\\16*8) BlockSize jjjjjjjj (+ExtB*256). ee = num extensions"
  		 ^client
  			pushClosureCopyNumCopiedValues: ((byte2 bitShift: -3) bitAnd: 7) + (extA // 16 bitShift: 3)
  			numArgs: (byte2 bitAnd: 7) + (extA \\ 16 bitShift: 3)
  			blockSize: byte3 + (extB bitShift: 8)].
  	bytecode = 251 ifTrue:
  		[^client pushRemoteTemp: byte2 inVectorAt: byte3].
  	bytecode = 252 ifTrue:
  		[^client storeIntoRemoteTemp: byte2 inVectorAt: byte3].
  	bytecode = 253 ifTrue:
  		[^client popIntoRemoteTemp: byte2 inVectorAt: byte3].
  	"**	254		11111110	kkkkkkkk	jjjjjjjj		branch If Not Instance Of Behavior/Array Of Behavior kkkkkkkk (+ Extend A * 256, where Extend A >= 0) distance jjjjjjjj (+ Extend B * 256, where Extend B >= 0)"
  	bytecode = 254 ifTrue: "The sign bit of extB inverts the operation.  Would like to have extB < -128, but this is good enough for now."
+ 		[literal := method literalAt: (extA bitShift: 8) + byte2 + 1.
+ 		 extB < 0 ifTrue: [^client branchIfInstanceOf: literal distance: (extB + 128 bitShift: 8) + byte3].
- 		[extB < 0 ifTrue: [^client branchIfInstanceOf: literal distance: (extB + 128 bitShift: 8) + byte3].
  		 ^client branchIfNotInstanceOf: literal distance: (extB bitShift: 8) + byte3].
  	^self unusedBytecode: client at: startPC!



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