Commit Graph

133 Commits

Author SHA1 Message Date
Nick Lewycky
f16120475e Move PR4517 to README.txt.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75098 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-09 04:03:30 +00:00
Dan Gohman
81db61a2e6 Factor the code for collecting IV users out of LSR into an IVUsers class,
and generalize it so that it can be used by IndVarSimplify. Implement the
base IndVarSimplify transformation code using IVUsers. This removes
TestOrigIVForWrap and associated code, as ScalarEvolution now has enough
builtin overflow detection and folding logic to handle all the same cases,
and more. Run "opt -iv-users -analyze -disable-output" on your favorite
loop for an example of what IVUsers does.

This lets IndVarSimplify eliminate IV casts and compute trip counts in
more cases. Also, this happens to finally fix the remaining testcases
in PR1301.

Now that IndVarSimplify is being more aggressive, it occasionally runs
into the problem where ScalarEvolutionExpander's code for avoiding
duplicate expansions makes it difficult to ensure that all expanded
instructions dominate all the instructions that will use them. As a
temporary measure, IndVarSimplify now uses a FixUsesBeforeDefs function
to fix up instructions inserted by SCEVExpander. Fortunately, this code
is contained, and can be easily removed once a more comprehensive
solution is available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71535 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-12 02:17:14 +00:00
Dan Gohman
1f3be1a1fe Fix two wording errors that Duncan spotted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71459 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 18:51:16 +00:00
Dan Gohman
0d9bb68d6d LLVM has unaligned loads and stores now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71449 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 18:06:05 +00:00
Dan Gohman
5c8274b5e3 Upgrade this example to new-style syntax.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71447 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 18:04:52 +00:00
Chris Lattner
32c5f17024 remove some done things: we have nocapture and SROA is smarter.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71443 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 17:41:40 +00:00
Chris Lattner
d919a8bc8a add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71442 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-11 17:36:33 +00:00
Eli Friedman
cea03cdb69 Remove a completed optimization. Add a potential optimization I ran
into.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71352 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-09 08:40:15 +00:00
Chris Lattner
352f3e5d37 add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67953 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-28 19:26:55 +00:00
Nick Lewycky
20babb112c Add a totally synthetic situation I came up with while looking at a bug in
related code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65437 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-25 06:52:48 +00:00
Torok Edwin
474479fce7 add note about sin
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65137 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-20 18:42:06 +00:00
Torok Edwin
e46a686dc2 add note about possible GEP improvement with fields of size 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62925 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-24 19:30:25 +00:00
Chris Lattner
256baa4b1f add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62760 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-22 07:16:03 +00:00
Dan Gohman
8289b05c4c Add a README entry noticed while investigating PR3216.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62558 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-20 01:07:33 +00:00
Chris Lattner
9fee08fce7 add some more crazy strlen and memcpy stuff I noticed in spec.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61918 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-08 07:34:55 +00:00
Chris Lattner
ffb08f569b add some notes about strlen craziness in eon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61917 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-08 06:52:57 +00:00
Chris Lattner
d23b799d7d add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61513 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-31 00:54:13 +00:00
Chris Lattner
9cf8ef63c6 add some notes for simplifylibcalls optimizations
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61385 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 20:52:52 +00:00
Chris Lattner
582048d5b8 add some more notes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61033 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 08:32:28 +00:00
Chris Lattner
8f416f3afd Add a testcase for GCC PR 23455, which lpre handles now. Add some
comments about why we're not getting other cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61032 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 07:49:24 +00:00
Chris Lattner
ef423ebdd1 gvn now hoists this load out of the hot non-call path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61028 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 06:34:48 +00:00
Chris Lattner
2dae65d13b move an entry, add some notes, remove a completed item (IMPLICIT_DEF)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60821 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-10 01:30:48 +00:00
Chris Lattner
630c99fd21 improve a note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60636 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-07 00:15:10 +00:00
Chris Lattner
6a09a74e46 some more PRE/GVN/DSE related notes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60633 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-06 22:52:12 +00:00
Chris Lattner
78a7e7c797 some random notes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60624 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-06 19:28:22 +00:00
Chris Lattner
88d84b245c add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60404 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-02 06:32:34 +00:00
Bill Wendling
3bdcda82a5 - Remove the buggy -X/C -> X/-C transform. This isn't valid when X isn't a
constant. If X is a constant, then this is folded elsewhere.

- Added a note to Target/README.txt to indicate that we'd like to implement
  this when we're able.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60399 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-02 05:12:47 +00:00
Bill Wendling
b3833d1eb9 Implement ((A|B)&1)|(B&-2) -> (A&1) | B transformation. This also takes care of
permutations of this pattern.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60312 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 01:07:11 +00:00
Bill Wendling
b01865c210 Add instruction combining for ((A&~B)|(~A&B)) -> A^B and all permutations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60291 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-30 13:52:49 +00:00
Bill Wendling
7f0ef6b325 Implement (A&((~A)|B)) -> A&B transformation in the instruction combiner. This
takes care of all permutations of this pattern.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60290 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-30 13:08:13 +00:00
Eli Friedman
4e16b29a6b Moving potential optimizations out of PR2330 into lib/Target/README.txt.
Hopefully this isn't too much stuff to dump into this file.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60285 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-30 07:36:04 +00:00
Nick Lewycky
d2f0db1b19 Also update the README.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60188 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:41:45 +00:00
Nick Lewycky
df563ca1f3 Add a synthetic missed optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60186 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:12:22 +00:00
Torok Edwin
61df3b751a move the note to the correct README
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58104 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-24 19:23:07 +00:00
Torok Edwin
db1b3bc276 add note about va_arg code on x86 and x86-64
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58103 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-24 19:20:05 +00:00
Dan Gohman
cb747c558c This is now partly done.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57734 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-17 21:39:27 +00:00
Chris Lattner
3b364cb986 move PR1941 here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57586 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-15 16:33:52 +00:00
Chris Lattner
db03983238 move PR1604 here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57582 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-15 16:06:03 +00:00
Chris Lattner
f4fee2a976 move PR1488 into this file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57579 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-15 16:02:15 +00:00
Chris Lattner
b7fe708b32 add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57557 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-15 05:53:25 +00:00
Chris Lattner
b1ac769873 this case is matched now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57096 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-05 02:16:12 +00:00
Chris Lattner
23f35bc3ae add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54985 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-19 06:22:16 +00:00
Chris Lattner
26e150f361 move some more stuff out of my email into readme.txt
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54603 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-10 01:14:08 +00:00
Chris Lattner
c90b866797 add a note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54602 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-10 00:47:21 +00:00
Chris Lattner
10c5d36ca9 Add a note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53535 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-14 00:19:59 +00:00
Nick Lewycky
517e1f5cd7 Peer through sext/zext when looking for not(cmp).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51819 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-31 19:01:33 +00:00
Nick Lewycky
4914db09a5 Yay us! Every one of these examples turns into icmp/zext/ret.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51818 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-31 18:20:26 +00:00
Chris Lattner
b5783106c4 trip count computation deficiency
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51222 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-17 15:37:38 +00:00
Nick Lewycky
8dd6505868 Moved from PR1570.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48965 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-30 19:07:11 +00:00
Chris Lattner
f70107fe1c add a note.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48583 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-20 04:46:13 +00:00