Man! Has anyone noticed that: 1) nsStr counts for 10M out of 25M in the bloat logs 2) nsStr is 20 bytes long 3) 8 bytes of nsStr are used for two booleans (mCharSize and mOwnsBuffer) With a simple 10-15 line change, I can shrink nsStr to 16 bytes, by making mCharSize a PRInt8 and making mOwnsBuffer a PRPackedBool, both 8 bytes. Rounded up to the nearest 4 bytes, these two variables still take 4 bytes, but it will save about 2 Megs in the bloat logs on tinderbox. I'm going to work on further reductions to roll these two boolean variables into the high bytes of mLength and mCapacity, reducing this object to a mere 8 bytes, but I'd like to get this short patch into 0.9.6 right now.

oops, assign to myself, I have the fix

I totally mucked up indentation in nsStr.h, but I'll fix that before landing.

cc'ing waterson for an sr=

sr=waterson

Comment on attachment 56622 [details] [diff] [review] shrink nsStr by 4 bytes Sure, low fruit. r=jag

in my tree, I also moved mCharSize and mOwnsBuffer after mStr/mUStr to make sure mStr/mUStr stay aligned (dumb compilers might not)

thanks guys, fixed!