560106 - Add missing 64-bit algebraic optimizations to ExprFilter

Status: RESOLVED FIXED

(Core Graveyard :: Nanojit, defect, P2)

Description

[Edwin Smith]

Several 32-bit optimizations in ExprFilter are missing their 64-bit couterparts:

* constant folding
* algebraic simplifications for op(x, imm64)

Comment 1

[Edwin Smith]

Attachment: Adds ALU op constant folding and algebraic simplifications

Comment 2

[Edwin Smith]

Attachment: (v2) Adds ALU op constant folding and algebraic simplifications

Handle more cases.  Now each 32-bit optimization in ExprFilter::ins2() should have a 64-bit counterpart.

Comment 3

[Edwin Smith]

Attachment: (v3) Adds ALU op constant folding and algebraic simplifications

Comment 4

[Edwin Smith]

Attachment: constant folding for LIR_i2q and ui2uq

Comment 5

[Andreas Gal :gal]

Comment on attachment 446973 [details] [diff] [review]
constant folding for LIR_i2q and ui2uq

immI() already returns int32_t but a bit overcasting for clarity can't hurt and it matches the uint case where its needed.

Comment 6

[Edwin Smith]

yup, i'm counting on sign extension, thats why I overcasted for clarity.

Comment 7

[Edwin Smith]

Comment on attachment 446973 [details] [diff] [review]
constant folding for LIR_i2q and ui2uq

NJ: i2q constant folding
http://hg.mozilla.org/projects/nanojit-central/rev/e6ce59a07d5f

Comment 8

[William Maddox]

Comment on attachment 446880 [details] [diff] [review]
(v3) Adds ALU op constant folding and algebraic simplifications

On line 619, insImmI(0) is returned in all cases.  Should be insImmQ(0) for LIR_xorq.

R+ with the above fix.

nits: I would prefer redundant explicit casts on unsigned shift arguments in the 64-bit case similar to those on signed arguments in the 32-bit case.  The fact that immI() returns int32_t and immQ() returns uint64_t is confusing.  Also, inside an #ifdef NANOJIT_64BIT, InsImmWord can be replaced with InsImmQ.

Comment 9

[Edwin Smith]

I'll update this once Bug 527512 lands, since it cleans up code.  I could also wait for bug 569753 (splitting up ExprFilter::ins2) to avoid making the problem worse before it gets better.  opinions?

Comment 10

[Nicholas Nethercote [inactive]]

http://hg.mozilla.org/tracemonkey/rev/04f69ec5483b

Comment 11

[Robert Sayre]

http://hg.mozilla.org/mozilla-central/rev/04f69ec5483b

Comment 12

[Robert Sayre]

http://hg.mozilla.org/mozilla-central/rev/001173ed203c