Commit Graph

29 Commits

Author SHA1 Message Date
Bob Wilson dcc54decd5 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.

llvm-svn: 163106
2012-09-03 05:15:15 +00:00
Craig Topper 2a40418a99 Change greater than to greater than or equal so that an identical sized store to the same offset is treated as completing overwriting.
llvm-svn: 161857
2012-08-14 07:32:05 +00:00
Eli Friedman 08ec0a8122 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.

llvm-svn: 161468
2012-08-08 02:17:32 +00:00
Dan Gohman ed7c24e2d9 Teach DeadStoreElimination to eliminate exit-block stores with phi addresses.
llvm-svn: 156558
2012-05-10 18:57:38 +00:00
Nuno Lopes 300d629924 teach DSE and isInstructionTriviallyDead() about calloc
llvm-svn: 156553
2012-05-10 17:14:00 +00:00
Nick Lewycky dd1d3df524 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.

llvm-svn: 142787
2011-10-24 04:35:36 +00:00
Nick Lewycky 32f8051d66 A non-escaping malloc in the entry block is not unlike an alloca. Do dead-store
elimination on them too.

llvm-svn: 142735
2011-10-22 21:59:35 +00:00
Eli Friedman 02e737b08e 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.

llvm-svn: 137527
2011-08-12 22:50:01 +00:00
Chris Lattner 80ed9dc9e5 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.

llvm-svn: 133337
2011-06-18 06:05:24 +00:00
Chris Lattner 026f5e61f0 fix a really nasty basicaa mod/ref calculation bug that was causing miscompilation of
UnitTests/ObjC/messages-2.m with the recent optimizer improvements.

llvm-svn: 131897
2011-05-23 05:15:43 +00:00
Chris Lattner 94fbdf3814 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!

llvm-svn: 120974
2010-12-06 01:48:06 +00:00
Chris Lattner b63ba73b1b 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.

llvm-svn: 120445
2010-11-30 19:12:10 +00:00
Chris Lattner 58b779e9c2 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.

llvm-svn: 120406
2010-11-30 07:23:21 +00:00
Chris Lattner c2e3445273 merge one more away
llvm-svn: 120375
2010-11-30 01:06:43 +00:00
Chris Lattner 7578d0df51 I already merged partial-overwrite.ll -> PartialStore.ll
Merge context-sensitive.ll -> simple.ll and upgrade it.

llvm-svn: 120374
2010-11-30 01:05:07 +00:00
Chris Lattner 43e3a98675 clean up DSE tests, removing some poorly reduced and useless old test,
merging more into other larger .ll files, filecheckizing along the way.

llvm-svn: 120373
2010-11-30 01:00:34 +00:00
Chris Lattner 90c4947df7 enhance basicaa to return "Mod" for a memcpy call when the
queried location doesn't overlap the source, and add a testcase.

llvm-svn: 120370
2010-11-30 00:43:16 +00:00
Chris Lattner 9a146372b5 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.

llvm-svn: 120368
2010-11-30 00:28:45 +00:00
Chris Lattner c3c754f750 my previous patch would cause us to start deleting some volatile
stores, fix and add a testcase.

llvm-svn: 120363
2010-11-30 00:12:39 +00:00
Benjamin Kramer e6840ef4b3 Fix some broken CHECK lines.
llvm-svn: 120332
2010-11-29 22:34:55 +00:00
Chris Lattner 2e8793482c fix PR8677, patch by Jakub Staszak!
llvm-svn: 120325
2010-11-29 21:59:31 +00:00
Chris Lattner e48c31ce33 implement PR8576, deleting dead stores with intervening may-alias stores.
llvm-svn: 119927
2010-11-21 07:34:32 +00:00
Chris Lattner 6e22221b37 file checkize
llvm-svn: 119926
2010-11-21 07:32:40 +00:00
Dan Gohman 02538ac4d3 Make BasicAliasAnalysis a normal AliasAnalysis implementation which
does normal initialization and normal chaining. Change the default
AliasAnalysis implementation to NoAlias.

Update StandardCompileOpts.h and friends to explicitly request
BasicAliasAnalysis.

Update tests to explicitly request -basicaa.

llvm-svn: 116720
2010-10-18 18:04:47 +00:00
Kenneth Uildriks 90fedc6ef9 Make opt default to not adding a target data string and update tests that depend on target data to supply it within the test
llvm-svn: 85900
2009-11-03 15:29:06 +00:00
Dan Gohman 1880092722 Change tests from "opt %s" to "opt < %s" so that opt doesn't see the
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.

llvm-svn: 81537
2009-09-11 18:01:28 +00:00
Dan Gohman 72a13d2476 Use opt -S instead of piping bitcode output through llvm-dis.
llvm-svn: 81257
2009-09-08 22:34:10 +00:00
Dan Gohman 9737a63ed8 Change these tests to feed the assembly files to opt directly, instead
of using llvm-as, now that opt supports this.

llvm-svn: 81226
2009-09-08 16:50:01 +00:00
Chris Lattner b839c05a05 rename *.llx -> *.ll, last batch.
llvm-svn: 49971
2008-04-19 22:32:52 +00:00