nicolas cellier wrote:
> Remaining performance is mostly explained by method inlining, which is 
> not desirable in SqNumberParser. It could however be subclassed with an 
> OptimizedSqueakFloatParser (I did not...).

Indeed. You should *very* seriously consider this. I'm including the 
tallies of the reader below (done with the Qwaq profiler which does 
sub-millisecond primitive sampling) and look how much time you spend 
elsewhere: Character>>digitValue is a bitch (going through 
EncodedCharSet every time) and PositionableStream>>atEnd is called a 
gigazillion times. Compare this with the streamlined version in 
ReadStream>>nextFloat and you can see where the difference is in inlining.

Cheers,
   - Andreas




----------------------- Float>>readFrom: --------------------------

100.0 (10,406)  Compiler  evaluate:in:to:notifying:ifFail:logged:
   100.0 (10,406)  TXmlConstructor class  DoIt
     100.0 (10,406)  TXmlConstructor class  runFloatTest:
      94.7 (9,854)  Float class  readFrom:
       |94.6 (9,844)  Float class [Number class]  readFrom:
       |  50.3 (5,234)  Float class [Number class] 
readRemainderOf:from:base:withSign:
       |    |26.0 (2,706)  Integer class  readFrom:base:
       |    |  |10.1 (1,051)  Character  digitValue
       |    |  |  |9.7 (1,009)  EncodedCharSet class  charsetAt:
       |    |  |  |  9.7 (1,009)  Array [SequenceableCollection] 
at:ifAbsent:
       |    |  |  |    9.1 (947)  Object  at:
       |    |  |7.5 (780)  ReadStream [PositionableStream]  peekFor:
       |    |  |  |5.8 (604)  PositionableStream  atEnd
       |    |  |  |1.7 (177)  ReadStream  next
       |    |  |5.1 (531)  PositionableStream  atEnd
       |    |  |3.2 (333)  ReadStream  next
       |    |  |  1.7 (177)  ByteString  at:
       |    |9.2 (957)  SmallInteger  asFloat
       |    |4.1 (427)  Float class [Number class] 
canParseExponentFor:base:from:
       |    |  |2.9 (302)  ByteString [SequenceableCollection]  includes:
       |    |  |  |2.9 (302)  ByteString [String]  indexOf:
       |    |  |  |  2.9 (302)  ByteString class 
indexOfAscii:inString:startingAt:
       |    |  |1.2 (125)  ReadStream [PositionableStream]  peek
       |    |3.9 (406)  ReadStream [PositionableStream]  peekFor:
       |    |  |3.5 (364)  PositionableStream  atEnd
       |    |2.7 (281)  Character  digitValue
       |    |  |2.6 (271)  EncodedCharSet class  charsetAt:
       |    |  |  2.6 (271)  Array [SequenceableCollection]  at:ifAbsent:
       |    |  |    2.1 (219)  Object  at:
       |    |2.2 (229)  Float class [Number class] 
canParseAsScaledDecimal...digits:base:sign:from:
       |    |  |1.8 (187)  ReadStream [PositionableStream]  peek
       |    |1.1 (114)  PositionableStream  atEnd
       |  30.3 (3,153)  Integer class  readFrom:base:
       |    |13.1 (1,363)  Character  digitValue
       |    |  |12.6 (1,311)  EncodedCharSet class  charsetAt:
       |    |  |  12.5 (1,301)  Array [SequenceableCollection]  at:ifAbsent:
       |    |  |    11.5 (1,197)  Object  at:
       |    |7.1 (739)  PositionableStream  atEnd
       |    |5.9 (614)  ReadStream [PositionableStream]  peekFor:
       |    |  |5.4 (562)  PositionableStream  atEnd
       |    |4.1 (427)  ReadStream  next
       |    |  2.0 (208)  ByteString  at:
       |  7.6 (791)  ReadStream [PositionableStream]  peekFor:
       |    |6.3 (656)  PositionableStream  atEnd
       |    |1.2 (125)  ReadStream  next
       |  6.5 (676)  ReadStream [Stream]  nextMatchAll:
       |    4.5 (468)  ByteString [SequenceableCollection]  do:
       |      |4.4 (458)  ArrayedCollection  size
       |    1.7 (177)  ReadStream  next
      3.7 (385)  ReadStream [PositionableStream]  skipSeparators
       |2.8 (291)  PositionableStream  atEnd
      1.6 (166)  PositionableStream  atEnd

**Leaves**
42.7 (4,443)  PositionableStream  atEnd
23.7 (2,466)  Object  at:
9.6 (999)  SmallInteger  asFloat
6.0 (624)  ByteString  at:
4.8 (499)  ArrayedCollection  size
4.7 (489)  ReadStream  next
3.0 (312)  ByteString class  indexOfAscii:inString:startingAt:

**Memory**
	old			+0 bytes
	young		+399,516 bytes
	used		+399,516 bytes
	free		-399,516 bytes

**GCs**
	full			0 totalling 0ms (0.0% uptime)
	incr		170 totalling 690ms (7.0% uptime), avg 4.0ms
	tenures		0
	root table	0 overflows





------------------------ Readstream>>nextFloat ------------------------

100.0 (744)  Compiler  evaluate:in:to:notifying:ifFail:logged:
   100.0 (744)  TXmlConstructor class  DoIt
     100.0 (744)  TXmlConstructor class  runFloatTest:
       100.0 (744)  ReadStream  nextFloat
         74.8 (557)  ByteString  byteAt:
         13.6 (101)  ByteString class  findFirstInString:inSet:startingAt:
         11.5 (86)  SmallInteger  asFloat

**Leaves**
74.9 (557)  ByteString  byteAt:
13.6 (101)  ByteString class  findFirstInString:inSet:startingAt:
11.5 (86)  SmallInteger  asFloat

**Memory**
	old			+0 bytes
	young		-562,888 bytes
	used		-562,888 bytes
	free		+562,888 bytes

**GCs**
	full			0 totalling 0ms (0.0% uptime)
	incr		13 totalling 18ms (2.0% uptime), avg 1.0ms
	tenures		0
	root table	0 overflows