This is James Iha's guitar part of this song, I hope this is the right tab, enjoy.

Song:1979
Artist:Smashing Pumpkins
Album:Mellon Collie and the Infinite Sadness
Tuning: Eb,Ab,Db,Gb,Bb,Eb.

Intro Riff:
Eb|--------------------------------------|
Bb|--------------------------------------|
Gb|-8888888/9\4444444--------------------|  repeat this until you get to the
Db|-xxxxxxxxxxxxxxxxx-6b6-4-2-4-6-999999-|  next part you need to listen to
Ab|-6666666/7\2222222-0-0-0-0-0-0-000000-|  the song for the timing.
Eb|-00000000000000000--------------------|

Eb|------------------------|
Bb|------------------------|
Gb|------------------------| play this part once and then go back to the Intro
Db|-4444444/99999999-------| riff.
Ab|-4444444/99999999-------|
Eb|-2222222/77777777-------|

Chorus:
Eb|----------------------------------|
Bb|----------------------------------|
Gb|----------------------------------|  repeat this 4 times
Db|-7777777777777-6b6-4-2-4-6-999999-|
Ab|-7777777777777-0-0-0-0-0-0-000000-|
Eb|-0000000000000--------------------|

then go back to the intro riff once again repeat it until you get to this riff:

Eb|-------------------------------|
Bb|-------------------------------|
Gb|-------------------------------|
Db|-4444444/77777777--------------|
Ab|-4444444/77777777--------------|
Eb|-2222222/55555555--------------|

go to the chorus riff again, repeat this 4 times, then play this riff:

Eb|---------------------------------|
Bb|---------------------------------|
Gb|-44444444444444/6666666\22222222-|
Db|-44444444444444/6666666\22222222-|
Ab|-22222222222222/4444444\00000000-|
Eb|---------------------------------|

play this riff once:

Eb|-----------------|
Bb|-----------------|
Gb|-----------------|
Db|-444444/99999999-|
Ab|-444444/99999999-|
Eb|-222222/77777777-|

these are the parts, all you have to do is put them in order.

Key:
/ Upslide
\ Downslide
b Bend