[Vm-dev] VM Maker: VMMaker.oscog-eem.1054.mcz
Nicolas Cellier
nicolas.cellier.aka.nice at gmail.com
Wed Feb 11 22:19:45 UTC 2015
2015-02-11 23:14 GMT+01:00 Eliot Miranda <eliot.miranda at gmail.com>:
>
> Hi Nicolas,
>
> On Wed, Feb 11, 2015 at 2:05 PM, Nicolas Cellier <
> nicolas.cellier.aka.nice at gmail.com> wrote:
>
>>
>> If I reformulate:
>>
>> 1) there is a speed-up consisting in bitAnd'ing bitOr'ing the Oop
>> (shifted integer value+tag) directly without need to decode anything when
>> both are immediate SmallInteger
>>
>
> Right.
>
>
>> 2) this speed-up is already performed in interpreter special bytecode
>> handling and/or in JIT
>>
>
> It wasn't, but it is now.
>
>
>> 3) so checking again in the primitive is a loss of time
>>
>
> Right.
>
>
>> 4) the primitive is there just in case the receiver and/or argument is a
>> LargePositiveInteger outside immediate range, but still fitting in an
>> unsigned long (32 or 64 bits)
>>
>
> Not quite. While in normal execution the primitive will only be called if
> one or other of the receiver and argument is not a SmallInteger, the
> primitive will be called whenever the debugger executes bitAnd: or bitXor:
> since the simulation machinery invokes the primitive, rather than
> simulating the inlining of the special selectors.
>
OK, it's good to keep this case in mind...
When debugging, I presume we can afford to be a tiny bit slower and allways
decode/encode the SmallIntegers.
Note that bitAnd'ing a positive SmallInteger with any LargeInteger
(positive or not) will allways answer a SmallInteger...
So we might create another optimization in the primitive for this case...
Or maybe it's too crooked ;)
Similarly, bitAnd'ing a negative SmallInteger with any LargeInteger will
never answer a SmallInteger.
> 2015-02-11 22:20 GMT+01:00 <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.1054.mcz
>>>
>>> ==================== Summary ====================
>>>
>>> Name: VMMaker.oscog-eem.1054
>>> Author: eem
>>> Time: 11 February 2015, 1:20:01.475 pm
>>> UUID: 3d511797-53fc-4848-b1ec-4b8a1eb0c0ff
>>> Ancestors: VMMaker.oscog-eem.1053
>>>
>>> Broaden primitiveBitAnd and primitiveBitOr for Spur
>>> 64-bits. Make the bytecodes handle the common
>>> SmallInteger op SmallInteger case.
>>>
>>> Fix C code for and endianness under simulation of
>>> Spur64BitMemoryManager>>fetchLong32:ofFloatObject:
>>>
>>> =============== Diff against VMMaker.oscog-eem.1053 ===============
>>>
>>> Item was changed:
>>> ----- Method: InterpreterPrimitives>>primitiveBitAnd (in category
>>> 'arithmetic integer primitives') -----
>>> primitiveBitAnd
>>> + <inline: false>
>>> | integerReceiver integerArgument |
>>> + integerArgument := self stackTop.
>>> + integerReceiver := self stackValue: 1.
>>> + "Comment out the short-cut. Either the inline interpreter
>>> bytecode or the JIT primitive will handle this case.
>>> + ((objectMemory isIntegerObject: integerArgument)
>>> + and: [objectMemory isIntegerObject: integerReceiver])
>>> + ifTrue: [self pop: 2 thenPush: (integerArgument bitAnd:
>>> integerReceiver)]
>>> + ifFalse:
>>> + ["objectMemory wordSize = 8
>>> + ifTrue:
>>> + [integerArgument := self
>>> positive64BitValueOf: integerArgument.
>>> + integerReceiver := self
>>> positive64BitValueOf: integerReceiver.
>>> + self successful ifTrue:
>>> + [self pop: 2 thenPush:
>>> (self positive64BitIntegerFor: (integerArgument bitAnd: integerReceiver))]]
>>> + ifFalse:
>>> + [integerArgument := self
>>> positive32BitValueOf: integerArgument.
>>> + integerReceiver := self
>>> positive32BitValueOf: integerReceiver.
>>> + self successful ifTrue:
>>> + [self pop: 2 thenPush:
>>> (self positive32BitIntegerFor: (integerArgument bitAnd:
>>> integerReceiver))]]"]"!
>>> - integerArgument := self popPos32BitInteger.
>>> - integerReceiver := self popPos32BitInteger.
>>> - self successful
>>> - ifTrue: [self push: (self positive32BitIntegerFor:
>>> - (integerReceiver bitAnd:
>>> integerArgument))]
>>> - ifFalse: [self unPop: 2]!
>>>
>>> Item was changed:
>>> ----- Method: InterpreterPrimitives>>primitiveBitOr (in category
>>> 'arithmetic integer primitives') -----
>>> primitiveBitOr
>>> + <inline: false>
>>> | integerReceiver integerArgument |
>>> + integerArgument := self stackTop.
>>> + integerReceiver := self stackValue: 1.
>>> + "Comment out the short-cut. Either the inline interpreter
>>> bytecode or the JIT primitive will handle this case.
>>> + ((objectMemory isIntegerObject: integerArgument)
>>> + and: [objectMemory isIntegerObject: integerReceiver])
>>> + ifTrue: [self pop: 2 thenPush: (integerArgument bitOr:
>>> integerReceiver)]
>>> + ifFalse:
>>> + ["objectMemory wordSize = 8
>>> + ifTrue:
>>> + [integerArgument := self
>>> positive64BitValueOf: integerArgument.
>>> + integerReceiver := self
>>> positive64BitValueOf: integerReceiver.
>>> + self successful ifTrue:
>>> + [self pop: 2 thenPush:
>>> (self positive64BitIntegerFor: (integerArgument bitOr: integerReceiver))]]
>>> + ifFalse:
>>> + [integerArgument := self
>>> positive32BitValueOf: integerArgument.
>>> + integerReceiver := self
>>> positive32BitValueOf: integerReceiver.
>>> + self successful ifTrue:
>>> + [self pop: 2 thenPush:
>>> (self positive32BitIntegerFor: (integerArgument bitOr:
>>> integerReceiver))]]"]"!
>>> - integerArgument := self popPos32BitInteger.
>>> - integerReceiver := self popPos32BitInteger.
>>> - self successful
>>> - ifTrue: [self push: (self positive32BitIntegerFor:
>>> - (integerReceiver bitOr:
>>> integerArgument))]
>>> - ifFalse: [self unPop: 2]!
>>>
>>> Item was changed:
>>> ----- Method: Spur64BitMemoryManager>>fetchLong32:ofFloatObject: (in
>>> category 'object access') -----
>>> fetchLong32: fieldIndex ofFloatObject: oop
>>> "index by word size, and return a pointer as long as the word
>>> size"
>>>
>>> | bits |
>>> (self isImmediateFloat: oop) ifFalse:
>>> [^self fetchLong32: fieldIndex ofObject: oop].
>>> bits := self smallFloatBitsOf: oop.
>>> ^self
>>> + cCode: [(self cCoerceSimple: (self addressOf: bits) to:
>>> #'int *') at: fieldIndex]
>>> + inSmalltalk:
>>> + [self flag: #endian.
>>> + fieldIndex = 0
>>> + ifTrue: [bits bitAnd: 16rFFFFFFFF]
>>> + ifFalse: [bits >> 32]]!
>>> - cCode: [self longAt: (self cCoerceSimple: (self
>>> addressOf: bits) to: #'char *')
>>> - + (fieldIndex <<
>>> self shiftForWord)]
>>> - inSmalltalk: [self flag: #endian.
>>> - fieldIndex = 0
>>> - ifTrue: [bits >> 32]
>>> - ifFalse: [bits bitAnd:
>>> 16rFFFFFFFF]]!
>>>
>>> Item was changed:
>>> ----- Method: StackInterpreter>>bytecodePrimBitAnd (in category
>>> 'common selector sends') -----
>>> bytecodePrimBitAnd
>>> + | rcvr arg |
>>> + arg := self internalStackTop.
>>> + rcvr := self internalStackValue: 1.
>>> + ((objectMemory isIntegerObject: arg)
>>> + and: [objectMemory isIntegerObject: rcvr]) ifTrue:
>>> + [self internalPop: 2 thenPush: (arg bitAnd: rcvr).
>>> + ^self fetchNextBytecode "success"].
>>>
>>> self initPrimCall.
>>> self externalizeIPandSP.
>>> self primitiveBitAnd.
>>> self internalizeIPandSP.
>>> + self successful ifTrue:
>>> + [^self fetchNextBytecode "success"].
>>> - self successful ifTrue: [^ self fetchNextBytecode "success"].
>>>
>>> messageSelector := self specialSelector: 14.
>>> argumentCount := 1.
>>> self normalSend!
>>>
>>> Item was changed:
>>> ----- Method: StackInterpreter>>bytecodePrimBitOr (in category 'common
>>> selector sends') -----
>>> bytecodePrimBitOr
>>> + | rcvr arg |
>>> + arg := self internalStackTop.
>>> + rcvr := self internalStackValue: 1.
>>> + ((objectMemory isIntegerObject: arg)
>>> + and: [objectMemory isIntegerObject: rcvr]) ifTrue:
>>> + [self internalPop: 2 thenPush: (arg bitOr: rcvr).
>>> + ^self fetchNextBytecode "success"].
>>>
>>> self initPrimCall.
>>> self externalizeIPandSP.
>>> self primitiveBitOr.
>>> self internalizeIPandSP.
>>> + self successful ifTrue:
>>> + [^self fetchNextBytecode "success"].
>>> - self successful ifTrue: [^ self fetchNextBytecode "success"].
>>>
>>> messageSelector := self specialSelector: 15.
>>> argumentCount := 1.
>>> self normalSend!
>>>
>>>
>>
>>
>
>
> --
> best,
> Eliot
>
>
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