Commit Graph

178 Commits

Author SHA1 Message Date
Benjamin Kramer
0d05acf592 Unquadratize SetVector removal loops in DSE.
Erasing from the beginning or middle of the vector is expensive, remove_if can
do it in linear time even though it's a bit ugly without lambdas.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165903 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-14 10:21:31 +00:00
Micah Villmow
3574eca1b0 Move TargetData to DataLayout.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165402 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-08 16:38:25 +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
1afd6bb939 Remove unused name of variable to quiet a warning. Also canonicalize a
declaration to use the same form as in the rest of the file. No functionality
change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164576 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-24 23:47:23 +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
Nick Lewycky
97a1a61447 Move all the calls to AA.getTargetLibraryInfo() to using a TLI member variable.
No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164560 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-24 22:07:09 +00:00
Benjamin Kramer
3be7584f40 DSE: Poking holes into a SetVector is expensive, avoid it if possible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163480 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-09 16:44:05 +00:00
Benjamin Kramer
8e0d1c03ca Make MemoryBuiltins aware of TargetLibraryInfo.
This disables malloc-specific optimization when -fno-builtin (or -ffreestanding)
is specified. This has been a problem for a long time but became more severe
with the recent memory builtin improvements.

Since the memory builtin functions are used everywhere, this required passing
TLI in many places. This means that functions that now have an optional TLI
argument, like RecursivelyDeleteTriviallyDeadFunctions, won't remove dead
mallocs anymore if the TLI argument is missing. I've updated most passes to do
the right thing.

Fixes PR13694 and probably others.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162841 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-29 15:32:21 +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
Nadav Rotem
a94d6e87c4 Clean whitespaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160668 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-24 10:51:42 +00:00
Nuno Lopes
9e72a79ef4 refactor the MemoryBuiltin analysis:
- provide more extensive set of functions to detect library allocation functions (e.g., malloc, calloc, strdup, etc)
 - provide an API to compute the size and offset of an object pointed by

Move a few clients (GVN, AA, instcombine, ...) to the new API.
This implementation is a lot more aggressive than each of the custom implementations being replaced.

Patch reviewed by Nick Lewycky and Chandler Carruth, thanks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158919 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-21 15:45:28 +00:00
Evan Cheng
6e406d8f11 It's not deterministic to iterate over SmallPtrSet. Replace it with SmallSetVector. Patch by Daniel Reynaud. rdar://11671029
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158594 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-16 04:28:11 +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
Craig Topper
858143816d Convert assert(0) to llvm_unreachable
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149967 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-07 05:05:23 +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
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
c7e5a6a2c6 Fixed bug in DeadStoreElimination commit r144239
Size of data being pointed to wasn't always being checked so some small writes were killing big writes

Fixes <rdar://problem/10426753>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144312 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-10 20:22:08 +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
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
Eli Friedman
b414142036 Enhance the memdep interface so that users can tell the difference between a dependency which cannot be calculated and a path reaching the entry point of the function. This patch introduces isNonFuncLocal, which replaces isUnknown in some cases.
Patch by Xiaoyi Guo.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141896 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-13 22:14:57 +00:00
Eli Friedman
1582e7f1e2 Add comment to clarify the behavior of a helper in DSE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139571 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-13 01:28:59 +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
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
8a552bb85a Misc mid-level changes for new 'fence' instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136205 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-27 01:08:30 +00:00
Chris Lattner
db125cfaf5 land David Blaikie's patch to de-constify Type, with a few tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18 04:54:35 +00:00
Eli Friedman
a990e071f2 Add "unknown" results for memdep, which mean "I don't know whether a dependence for the given instruction exists in the given block". This cleans up all the existing hacks in memdep which represent this concept by returning clobber with various unrelated instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133031 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-15 00:47:34 +00:00
Chris Lattner
7a2bdde0a0 Fix a ton of comment typos found by codespell. Patch by
Luis Felipe Strano Moraes!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129558 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-15 05:18:47 +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
Benjamin Kramer
ec3f227820 DSE: Remove an early exit optimization that depended on the ordering of a SmallPtrSet.
Fixes PR9569 and will hopefully make selfhost on ASLR-enabled systems more deterministic.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128482 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-29 20:28:57 +00:00
Bill Wendling
1a4d58af09 Simplification noticed by Frits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128333 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-26 09:32:07 +00:00
Bill Wendling
150c4a1a89 Rework the logic that determines if a store completely overlaps an ealier store.
There are two ways that a later store can comletely overlap a previous store:

1. They both start at the same offset, but the earlier store's size is <= the
   later's size, or
2. The earlier store's offset is > the later's offset, but it's offset + size
   doesn't extend past the later's offset + size.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128332 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-26 08:02:59 +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
Dan Gohman
bd1801b555 Give GetUnderlyingObject a TargetData, to keep it in sync
with BasicAA's DecomposeGEPExpression, which recently began
using a TargetData. This fixes PR8968, though the testcase
is awkward to reduce.

Also, update several off GetUnderlyingObject's users
which happen to have a TargetData handy to pass it in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124134 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-24 18:53:32 +00:00
Cameron Zwarich
301278719b Remove code for updating dominance frontiers and some outdated references to
dominance and post-dominance frontiers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123725 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-18 04:11:31 +00:00
Dan Gohman
5034dd318a Move Value::getUnderlyingObject to be a standalone
function so that it can live in Analysis instead of
VMCore.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121885 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 20:02:24 +00:00
Chris Lattner
29d8d6b039 Use a stronger predicate here, pointed out by Duncan
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121040 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 21:48:10 +00:00
Chris Lattner
a9d4da85d6 add some DEBUG statements.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121038 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-06 21:13:51 +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