[LLVMdev] Testcases where GVN uses too much memory?

Duncan P. N. Exon Smith
Sat, 03 May 2014 00:56:17 -0000

I've heard a few times, "GVN uses too much memory."  The real fix
is probably a rewrite of some sort, but that's not what this email
is about.

I have a few patches that should *incrementally* reduce its memory
usage.  Keyword being "should", because I haven't observed an
improvement... in fact, I haven't seen it using much memory at all.

Does anyone have a specific testcase where GVN uses gobs of memory?

I heard a rumour that gambitc can repro this, but I don't have time
right now to look for and isolate a testcase.  If someone else has
one handy, I'd appreciate if you could send it across.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-GVN-Avoid-BumpPtrAllocator-leak-in-performPRE.patch
Type: application/octet-stream
Size: 4546 bytes
Desc: not available
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20140502/72eb1a26/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0002-GVN-Don-t-shuffle-entries-in-replaceInLeaderTable.patch
Type: application/octet-stream
Size: 1994 bytes
Desc: not available
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20140502/72eb1a26/attachment-0001.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0003-GVN-Optimize-Expression-for-size.patch
Type: application/octet-stream
Size: 8228 bytes
Desc: not available
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20140502/72eb1a26/attachment-0002.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0004-GVN-Change-from-a-linked-list-to-a-vector.patch
Type: application/octet-stream
Size: 8346 bytes
Desc: not available
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20140502/72eb1a26/attachment-0003.obj>