Commit Graph

108 Commits

Author SHA1 Message Date
Nick Lewycky
fe4a778f6e Make this test check the transforms it's actually doing. Also add a test that it
doesn't transform the trivially unsafe case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164617 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-25 18:17:38 +00:00
Nick Lewycky
24ab21c691 Don't forget that strcpy and friends return a pointer to the destination, so
it's not a dead store if that pointer is used. Whoops!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164583 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-25 01:55:59 +00:00
Nick Lewycky
3dbefbd9bb Teach DSE that strcpy, strncpy, strcat and strncat are all stores which may be
dead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164561 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-24 22:09:10 +00:00
Bob Wilson
84451a110d Fix more fallout from r158919, similar to PR13547.
This code used to only handle malloc-like calls, which do not read memory.
r158919 changed it to check isNoAliasFn(), which includes strdup-like and
realloc-like calls, but it was not checking for dependencies on the memory
read by those calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163106 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-03 05:15:15 +00:00
Craig Topper
750d7616c6 Change greater than to greater than or equal so that an identical sized store to the same offset is treated as completing overwriting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161857 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-14 07:32:05 +00:00
Eli Friedman
1b88fc0122 isAllocLikeFn is allowed to return true for functions which read memory; make
sure we account for that correctly in DeadStoreElimination.  Fixes a regression
from r158919.  PR13547.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161468 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-08 02:17:32 +00:00
Dan Gohman
b401e3bd16 Teach DeadStoreElimination to eliminate exit-block stores with phi addresses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156558 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-10 18:57:38 +00:00
Nuno Lopes
e54874471c teach DSE and isInstructionTriviallyDead() about calloc
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156553 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-10 17:14:00 +00:00
Pete Cooper
9e1154cf5b Reverted r152620 - DSE: Shorten memset when a later store overwrites the start of it. There were all sorts of buildbot issues
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151621 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-28 05:06:24 +00:00
Pete Cooper
a116623e06 DSE: Shorten memset when a later store overwrites the start of it
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151620 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-28 04:27:10 +00:00
Rafael Espindola
a515b4e014 Add testcase for the previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151475 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-26 05:49:57 +00:00
Eli Bendersky
0f0c411079 Replace all instances of dg.exp file with lit.local.cfg, since all tests are run with LIT now and now Dejagnu. dg.exp is no longer needed.
Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150664 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-16 06:28:33 +00:00
Nick Lewycky
c9b98ad7a7 Fix infinite loop in DSE when deleting a free in a reachable loop that's also
trivially infinite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146197 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-08 22:36:35 +00:00
Pete Cooper
de2e27cc52 Fixed deadstoreelimination bug where negative indices were incorrectly causing the optimisation to occur
Turns out long long + unsigned long long is unsigned.  Doh!

Fixes http://llvm.org/bugs/show_bug.cgi?id=11455

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145731 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-03 00:04:30 +00:00
Nick Lewycky
f8f558d9e1 Fix typo in test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144774 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-16 03:56:38 +00:00
Nick Lewycky
ae10dd2859 Merge isObjectPointerWithTrustworthySize with getPointerSize. Use it when
looking at the size of the pointee. Fixes PR11390!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144773 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-16 03:49:48 +00:00
Pete Cooper
5ccb0825ed DeadStoreElimination can now trim the size of a store if the end of the store is dead.
Currently checks alignment and killing stores on a power of 2 boundary as this is likely
to trim the size of the earlier store without breaking large vector stores into scalar ones.

Fixes <rdar://problem/10140300>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144239 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-09 23:07:35 +00:00
Nick Lewycky
336b88dac8 Do simple cross-block DSE when we encounter a free statement. Fixes PR11240.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143808 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-05 10:48:42 +00:00
Daniel Dunbar
28eb1c5217 Speculatively revert "DeadStoreElimination can now trim the size of a store if
the end of it is dead.", which appears to break bootstrapping LLVM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143668 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-04 00:48:26 +00:00
Pete Cooper
2d32b86543 DeadStoreElimination can now trim the size of a store if the end of it is dead.
Only currently done if the later store is writing to a power of 2 address or 
has the same alignment as the earlier store as then its likely to not break up
large stores into smaller ones

Fixes <rdar://problem/10140300>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143630 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-03 18:01:56 +00:00
Nick Lewycky
4a3935c27e A dead malloc, a free(NULL) and a free(undef) are all trivially dead
instructions.

This doesn't introduce any optimizations we weren't doing before (except
potentially due to pass ordering issues), now passes will eliminate them sooner
as part of their own cleanups.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142787 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-24 04:35:36 +00:00
Nick Lewycky
4d882aae2a A non-escaping malloc in the entry block is not unlike an alloca. Do dead-store
elimination on them too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142735 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-22 21:59:35 +00:00
Owen Anderson
81856f7313 Try again at r138809 (make DSE more aggressive in removing dead stores at the end of a function), now with less deleting stores before memcpy's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139150 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 18:14:09 +00:00
Owen Anderson
1333abc785 Remove empty file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138830 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-30 21:17:20 +00:00
Owen Anderson
54c4735db3 Speculatively revert r138809 in an attempt to fix DragonEgg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138829 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-30 21:11:06 +00:00
Owen Anderson
6e4be237b0 When walking backwards to eliminate final stores to allocas at the end of a function, encountering an unrelated store should not cause us to give up like encountering a load does.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138809 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-30 18:51:55 +00:00
Eli Friedman
56efe24431 Atomic load/store handling for the passes using memdep (GVN, DSE, memcpyopt).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137888 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-17 22:22:24 +00:00
Eli Friedman
f03bb260c9 Move "atomic" and "volatile" designations on instructions after the opcode
of the instruction.

Note that this change affects the existing non-atomic load and store
instructions; the parser now accepts both forms, and the change is noted
in the release notes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137527 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-12 22:50:01 +00:00
Chris Lattner
b85e4eba85 rip out a ton of intrinsic modernization logic from AutoUpgrade.cpp, which is
for pre-2.9 bitcode files.  We keep x86 unaligned loads, movnt, crc32, and the
target indep prefetch change.

As usual, updating the testsuite is a PITA.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133337 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-18 06:05:24 +00:00
Chris Lattner
26b0000166 manually upgrade a bunch of tests to modern syntax, and remove some that
are either unreduced or only test old syntax.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133228 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-17 03:14:27 +00:00
Chris Lattner
c10ecd8f23 fix a really nasty basicaa mod/ref calculation bug that was causing miscompilation of
UnitTests/ObjC/messages-2.m with the recent optimizer improvements.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131897 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-23 05:15:43 +00:00
Bill Wendling
31d244ead5 * The DSE code that tested for overlapping needed to take into account the fact
that one of the numbers is signed while the other is unsigned. This could lead
  to a wrong result when the signed was promoted to an unsigned int.

* Add the data layout line to the testcase so that it will test the appropriate
  thing.

Patch by David Terei!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128577 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30 21:37:19 +00:00
Bill Wendling
e420449e80 PR9561: A store with a negative offset (via GEP) could erroniously say that it
completely overlaps a previous store, thus mistakenly deleting that store. Check
for this condition.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128319 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-26 01:20:37 +00:00
Chris Lattner
cc10244d77 Fix PR8728, a miscompilation I recently introduced. When optimizing
memcpy's like:
  memcpy(A, B)
  memcpy(A, C)

we cannot delete the first memcpy as dead if A and C might be aliases.
If so, we actually get:

  memcpy(A, B)
  memcpy(A, A)

which is not correct to transform into:

  memcpy(A, A)

This patch was heavily influenced by Jakub Staszak's patch in PR8728, thanks
Jakub!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120974 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 01:48:06 +00:00
Chris Lattner
3161ae1867 Enhance DSE to handle the variable index case in PR8657.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120498 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 23:43:23 +00:00
Chris Lattner
a04096580a teach DSE to use GetPointerBaseWithConstantOffset to analyze
may-aliasing stores that partially overlap with different base
pointers.  This implements PR6043 and the non-variable part of
PR8657


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120485 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 23:05:20 +00:00
Chris Lattner
55ee75d571 enhance isRemovable to refuse to delete volatile mem transfers
now that DSE hacks on them.  This fixes a regression I introduced,
by generalizing DSE to hack on transfers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120445 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 19:12:10 +00:00
Chris Lattner
cf82dc376a Rewrite the main DSE loop to be written in terms of reasoning
about pairs of AA::Location's instead of looking for MemDep's
"Def" predicate.  This is more powerful and general, handling
memset/memcpy/store all uniformly, and implementing PR8701 and
probably obsoleting parts of memcpyoptimizer.

This also fixes an obscure bug with init.trampoline and i8
stores, but I'm not surprised it hasn't been hit yet.  Enhancing
init.trampoline to carry the size that it stores would allow
DSE to be much more aggressive about optimizing them.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120406 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 07:23:21 +00:00
Chris Lattner
feea8fb6b4 merge one more away
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120375 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 01:06:43 +00:00
Chris Lattner
8a2dc0233f I already merged partial-overwrite.ll -> PartialStore.ll
Merge context-sensitive.ll -> simple.ll and upgrade it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120374 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 01:05:07 +00:00
Chris Lattner
75aa30bb1c clean up DSE tests, removing some poorly reduced and useless old test,
merging more into other larger .ll files, filecheckizing along the way.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120373 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 01:00:34 +00:00
Chris Lattner
13815d9d3e enhance basicaa to return "Mod" for a memcpy call when the
queried location doesn't overlap the source, and add a testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120370 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 00:43:16 +00:00
Chris Lattner
201d1e56bb Teach basicaa that memset's modref set is at worst "mod" and never
contains "ref".

Enhance DSE to use a modref query instead of a store-specific hack
to generalize the "ignore may-alias stores" optimization to handle
memset and memcpy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120368 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 00:28:45 +00:00
Chris Lattner
184d1ba738 my previous patch would cause us to start deleting some volatile
stores, fix and add a testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120363 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30 00:12:39 +00:00
Benjamin Kramer
8ad87ab166 Fix some broken CHECK lines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120332 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-29 22:34:55 +00:00
Chris Lattner
e9e973018a fix PR8677, patch by Jakub Staszak!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120325 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-29 21:59:31 +00:00
Chris Lattner
f6f1f062cc implement PR8576, deleting dead stores with intervening may-alias stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119927 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-21 07:34:32 +00:00
Chris Lattner
b7dfb970e6 file checkize
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119926 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-21 07:32:40 +00:00
Dan Gohman
720a2ed6d9 Enhance DSE to handle the case where a free call makes more than
one store dead. This is especially noticeable in
SingleSource/Benchmarks/Shootout/objinst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-12 02:19:17 +00:00
Dan Gohman
02df7e90cf Filecheckize.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118874 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-12 02:02:39 +00:00