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<base href="https://bugs.llvm.org/">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - opt -enable-new-pm=0 -loop-deletion fails with Assertion `!isInvalid() && "Loop not in a valid state!"' failed."
href="https://bugs.llvm.org/show_bug.cgi?id=49967">49967</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>opt -enable-new-pm=0 -loop-deletion fails with Assertion `!isInvalid() && "Loop not in a valid state!"' failed.
</td>
</tr>
<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Loop Optimizer
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>mikael.holmen@ericsson.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
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<div>
<pre>Created <span class=""><a href="attachment.cgi?id=24755" name="attach_24755" title="bbi-55148.ll reproducer">attachment 24755</a> <a href="attachment.cgi?id=24755&action=edit" title="bbi-55148.ll reproducer">[details]</a></span>
bbi-55148.ll reproducer
llvm commit: c3f12714641
Reproduce with:
opt -enable-new-pm=0 -loop-deletion -o /dev/null bbi-55148.ll
Result:
opt: ../include/llvm/Analysis/LoopInfo.h:123: bool
llvm::LoopBase<llvm::BasicBlock, llvm::Loop>::contains(const LoopT *) const
[BlockT = llvm::BasicBlock, LoopT = llvm::Loop]: Assertion `!isInvalid() &&
"Loop not in a valid state!"' failed.
PLEASE submit a bug report to <a href="https://bugs.llvm.org/">https://bugs.llvm.org/</a> and include the crash
backtrace.
Stack dump:
0. Program arguments: /repo/uabelho/master-github/llvm/build-all/bin/opt
-enable-new-pm=0 -loop-deletion -o /dev/null bbi-55148.ll
1. Running pass 'Function Pass Manager' on module 'bbi-55148.ll'.
2. Running pass 'Loop Pass Manager' on function '@test'
3. Running pass 'Delete dead loops' on basic block '%vector.ph'
Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH
or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm3sys15PrintStackTraceERNS_11raw_ostreamEi+0x23)[0x294f683]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm3sys17RunSignalHandlersEv+0xee)[0x294d33e]
/repo/uabelho/master-github/llvm/build-all/bin/opt[0x294fb46]
/lib64/libpthread.so.0(+0xf630)[0x7f8cb537e630]
/lib64/libc.so.6(gsignal+0x37)[0x7f8cb2ab1387]
/lib64/libc.so.6(abort+0x148)[0x7f8cb2ab2a78]
/lib64/libc.so.6(+0x2f1a6)[0x7f8cb2aaa1a6]
/lib64/libc.so.6(+0x2f252)[0x7f8cb2aaa252]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution18computeSCEVAtScopeEPKNS_4SCEVEPKNS_4LoopE+0xf76)[0x1aa7116]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution14getSCEVAtScopeEPKNS_4SCEVEPKNS_4LoopE+0x7c)[0x1a9f2cc]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution24computeExitLimitFromICmpEPKNS_4LoopEPNS_8ICmpInstEbbb+0x9a)[0x1a9d77a]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution28computeExitLimitFromCondImplERNS0_14ExitLimitCacheEPKNS_4LoopEPNS_5ValueEbbb+0xd8)[0x1a9cee8]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution30computeExitLimitFromCondCachedERNS0_14ExitLimitCacheEPKNS_4LoopEPNS_5ValueEbbb+0xe7)[0x1a9ca27]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution16computeExitLimitEPKNS_4LoopEPNS_10BasicBlockEb+0x5d0)[0x1a9c140]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution25computeBackedgeTakenCountEPKNS_4LoopEb+0x290)[0x1a98c10]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution20getBackedgeTakenInfoEPKNS_4LoopE+0x1ba)[0x1a9738a]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm15ScalarEvolution21getBackedgeTakenCountEPKNS_4LoopENS0_13ExitCountKindE+0x24)[0x1a983f4]
/repo/uabelho/master-github/llvm/build-all/bin/opt[0x26d5f6c]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm13LPPassManager13runOnFunctionERNS_8FunctionE+0x75b)[0x19eb04b]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm13FPPassManager13runOnFunctionERNS_8FunctionE+0x47f)[0x2155e5f]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm13FPPassManager11runOnModuleERNS_6ModuleE+0x38)[0x215c7b8]
/repo/uabelho/master-github/llvm/build-all/bin/opt(_ZN4llvm6legacy15PassManagerImpl3runERNS_6ModuleE+0x35d)[0x215642d]
/repo/uabelho/master-github/llvm/build-all/bin/opt(main+0x3137)[0x7808a7]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7f8cb2a9d555]
/repo/uabelho/master-github/llvm/build-all/bin/opt[0x76b8f5]
Abort
This starts happening with commit faf9f11589ce:
[SCEV] Don't walk uses of phis without SCEV expression when forgetting
I've run into some cases where a large fraction of compile-time is
spent invalidating SCEV. One of the causes is forgetLoop(), which
walks all values that are def-use reachable from the loop header
phis. When invalidating a topmost loop, that might be close to all
values in a function. Additionally, it's fairly common for there to
not actually be anything to invalidate, but we'll still be performing
this walk again and again.
My first thought was that we don't need to continue walking the uses
if the current value doesn't have a SCEV expression. However, this
isn't quite right, because SCEV construction can skip over values
(e.g. for a chain of adds, we might only create a SCEV expression
for the final value).
What this patch does instead is to only walk the (full) def-use chain
of loop phis that have a SCEV expression. If there's no expression
for a phi, then we also don't have any dependent expressions to
invalidate.
Differential Revision: <a href="https://reviews.llvm.org/D100264">https://reviews.llvm.org/D100264</a></pre>
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