103343 - Check for IsEmpty before more expensive value check

Status: RESOLVED FIXED

(Toolkit :: Form Manager, defect)

Description

[timeless]

while popping around the jprof profiling for bug 77073

It seems to me that we can save some time in the not too rare case where there
is no input type.

Comment 1

[timeless]

Attachment: reorder IsEmpty before expensive string comparison

Comment 2

[timeless]

Comment on attachment 52249 [details] [diff] [review]
reorder IsEmpty before expensive string comparison

()s in wrong place. sorry

Comment 3

[timeless]

Attachment: correctly reorder IsEmpty before expensive string comparison

Comment 4

[Boris Zbarsky [:bzbarsky]]

Actually... there is a futher speedup here.  How about:

+            (type.IsEmpty() ||
+             (Compare(type, NS_LITERAL_STRING("text"),
+                      nsCaseInsensitiveStringComparator()) == 0))) {

That avoids the conversion as well.

Comment 5

[Stephen P. Morse]

r=morse for Zbarsky's modification to patch

cc'ing alecf for sr

Comment 6

[Alec Flett]

sr=alecf on that second iteration...

Comment 7

[timeless]

:-)

Comment 8

[timeless]

fix checked in

Comment 9

[jag (Peter Annema)]

I think it would've been wiser to determine how often situation A happens, and
how often situation B happens. If A happens more often than B, testing for
situation B before testing for situation A will only slow the A case down, no
matter how much cheaper B is than A.

(A == Compare, B == IsEmpty).