15 Commits

Author SHA1 Message Date
Owen Anderson
d989711844 Fix file header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40440 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-23 18:30:37 +00:00
Owen Anderson
ce17b1c1f8 Take advantage of undefined behavior if the source program tries to GEP
beyond the end of an alloca to make FastDSE faster and more aggressive.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39945 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-16 23:34:39 +00:00
Owen Anderson
faac518ce0 Add support for walking up memory def chains, which enables finding many more
dead stores on 400.perlbench.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39929 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-16 21:52:50 +00:00
Owen Anderson
a08971559d Handle GEPs with all-zero indices in the same way we handle pointer-pointer bitcasts. Also, fix a potentia infinite loop.
This brings FastDSE to parity with old DSE on 175.vpr.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39839 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-13 22:50:48 +00:00
Owen Anderson
3e8d001799 Be more aggressive in removing dead stores, and in removing instructions trivially dead after DSE.
This drastically improves the effect of FastDSE on kimwitu++.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39819 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-13 18:26:26 +00:00
Owen Anderson
43b2676cc2 Reimplement removing stores to allocas at the end of a function. This should be safe now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39790 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-12 21:41:30 +00:00
Owen Anderson
dd61c2b25c Make the condition-checking for free with non-trivial dependencies more correct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39789 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-12 18:08:51 +00:00
Owen Anderson
1b4542b6df Remove the end-block handling code. It was unsafe, and making it safe would have resulted in falling back to the slow DSE case. I need to think some more about the right way to handle this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39788 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-12 17:52:20 +00:00
Gabor Greif
3b0a7ea66e checked in as obvious,
thanks Benoit Boissinot!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39774 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-12 13:31:38 +00:00
Owen Anderson
1cb960a4bb Let MemoryDependenceAnalysis take care of updating AliasAnalysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39769 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-12 00:06:21 +00:00
Owen Anderson
a96c1f665a Handle the case where an entire structure is freed, and its dependency is a store to a field within
that structure.

Also, refactor the runOnBasicBlock() function, splitting some of the special cases into separate functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39762 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-11 23:19:17 +00:00
Owen Anderson
6f46d65104 Add support for eliminate stores to stack-allocated memory locations at the end
of a function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39754 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-11 21:06:56 +00:00
Owen Anderson
2655adb3b2 Handle eliminating stores that occur right before a free.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39753 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-11 20:38:34 +00:00
Owen Anderson
bfbfb3c464 Clean up a few things based on Chris' feedback.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39747 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-11 19:03:09 +00:00
Owen Anderson
b77c457cc8 Add FastDSE, a new algorithm for doing dead store elimination. This algorithm is not as accurate
as the current DSE, but it only a linear scan over each block, rather than quadratic.  Eventually
(once it has been improved somewhat), this will replace the current DSE.

NOTE: This has not yet been extensively tested.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@38517 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-11 00:46:18 +00:00