assertion failure: Cannot find callsite to remove!

[llvmbot]

Bugzilla Link	3367
Resolution	FIXED
Resolved on	Apr 24, 2010 07:06
Version	2.4
OS	Windows XP
Depends On	llvm/llvm-bugzilla-archive#3601
Attachments	bitcode file, suggested fix
Reporter	LLVM Bugzilla Contributor
CC	@jayfoad,@nlewycky

Extended Description

With the attached bitcode file I get:

$ opt -f -o /dev/null stripped.bc -inline -prune-eh
opt: /home/foad/svn/llvm-project/llvm/trunk/lib/Analysis/IPA/CallGraph.cpp:264: void llvm::CallGraphNode::removeCallEdgeFor(llvm::CallSite): Assertion `i && "Cannot find callsite to remove!"' failed.
/home/foad/llvm/objdir-svn/Debug/bin/opt[0x86d2b66]
/home/foad/llvm/objdir-svn/Debug/bin/opt[0x86d2c96]
[0xb7fa5400]
/lib/i686/cmov/libc.so.6(abort+0x188)[0xb7d26018]
/lib/i686/cmov/libc.so.6(__assert_fail+0xee)[0xb7d1d5be]
/home/foad/llvm/objdir-svn/Debug/bin/opt(_ZN4llvm13CallGraphNode17removeCallEdgeForENS_8CallSiteE+0x41)[0x8561d41]
/home/foad/llvm/objdir-svn/Debug/bin/opt[0x83f8e31]
/home/foad/llvm/objdir-svn/Debug/bin/opt[0x83f9239]
/home/foad/llvm/objdir-svn/Debug/bin/opt[0x83f9506]
/home/foad/llvm/objdir-svn/Debug/bin/opt(_ZN105_GLOBAL__N__home_foad_svn_llvm_project_llvm_trunk_lib_Analysis_IPA_CallGraphSCCPass.cpp_00000000_EE43971E13CGPassManager11runOnModuleERN4llvm6ModuleE+0x161)[0x8564bb7]
/home/foad/llvm/objdir-svn/Debug/bin/opt(_ZN4llvm13MPPassManager11runOnModuleERNS_6ModuleE+0xcd)[0x865f461]
/home/foad/llvm/objdir-svn/Debug/bin/opt(_ZN4llvm15PassManagerImpl3runERNS_6ModuleE+0x74)[0x8660df6]
/home/foad/llvm/objdir-svn/Debug/bin/opt(_ZN4llvm11PassManager3runERNS_6ModuleE+0x1b)[0x8660e4d]
/home/foad/llvm/objdir-svn/Debug/bin/opt(main+0x11e3)[0x839ce81]
/lib/i686/cmov/libc.so.6(__libc_start_main+0xe5)[0xb7d0f455]
/home/foad/llvm/objdir-svn/Debug/bin/opt(__gxx_personality_v0+0x355)[0x838d361]
Aborted

This happens with both the 2.4 release and a fairly recent head of svn build. I'm using Linux/x86.

[llvmbot]

If you like the fix, it would be nice to have it in 2.5 too. Thanks!

Also, I'll try to come up with a smaller test case. The one I attached is quite big when you disassemble it.

[llvmbot]

smaller test case
Here's my minimal test case.

[nlewycky]

Fixed in r63600.

[nlewycky]

testcase proving the "suggested fix" wrong
The suggested fix makes minisat fail, bugpoint reduced testcase attached.

The problem with the line (*CG)->replaceCallSite(CI, II) is that the CG hasn't yet been updated to see CI if CI comes from the inlined callee.

[llvmbot]

The suggested fix makes minisat fail, bugpoint reduced testcase attached.

In what way does this reduced testcase fail? I don't see any assertion failures if I run "opt -inline -prune-eh" or "opt -std-compile-opts" on it, with my patch applied.

[llvmbot]

Nick, can you please explain how I can reproduce the "minisat" failure? I'm happy to investigate this, as I'd still like to get a fix accepted for the bug I originally reported. Thanks.

[nlewycky]

I just did a standard nightly run, "make TEST=nightly report.html" from projects/llvm-test. It showed minisat having failed, so I bugpointed it. Sorry I don't have reduced steps for you, but I entirely forget what the symptom was.

[llvmbot]

The suggested fix makes minisat fail, bugpoint reduced testcase attached.

I've finally worked out the way to reproduce this failure with the reduced test case:

$ opt -f -o /dev/null b.bc -inline -loop-rotate -loop-unswitch
opt: /home/foad/svn/llvm-project/llvm/trunk/lib/Analysis/IPA/CallGraph.cpp:304: void llvm::CallGraphNode::replaceCallSite(llvm::CallSite, llvm::CallSite): Assertion `I != CalledFunctions.end() && "Cannot find callsite to replace!"' failed.
0 opt 0x083ea123
1 libc.so.6 0xb7c8b018 abort + 392
2 libc.so.6 0xb7c825be __assert_fail + 238
3 opt 0x082727bc
Aborted

[llvmbot]

The suggested fix makes minisat fail, bugpoint reduced testcase attached.

I believe this is an unrelated latent bug that my patch has provoked. I've raised bug 3601 on it.

[llvmbot]

suggested fix that works around bug 3601
Here's a new version of my suggested fix. It works around the problem of bug 3601, which means that the call graph might not be as up-to-date as it should be.

The previous version of my suggested fix caused an assertion failure when building minisat; this version doesn't.

[llvmbot]

I can still reproduce the original bug with a Debug build of HEAD of svn, like this:

$ llvm-as -o - small.ll | opt -f -o /dev/null -inline -prune-eh
opt: /home/foad/svn/llvm-project/llvm/trunk/lib/Analysis/IPA/CallGraph.cpp:268: void llvm::CallGraphNode::removeCallEdgeFor(llvm::CallSite): Assertion `I != CalledFunctions.end() && "Cannot find callsite to remove!"' failed.
0 opt 0x086a965e
1 opt 0x086a9b90
2 0xb7f5c400 __kernel_sigreturn + 0
3 libc.so.6 0xb7cdd018 abort + 392
4 libc.so.6 0xb7cd45be __assert_fail + 238
5 opt 0x084ffd2b llvm::CallGraphNode::removeCallEdgeFor(llvm::CallSite) + 167
6 opt 0x08371a1b
7 opt 0x08371e1c
8 opt 0x083720db
9 opt 0x08503191
10 opt 0x0862a8e6 llvm::MPPassManager::runOnModule(llvm::Module&) + 238
11 opt 0x0862c3b6 llvm::PassManagerImpl::run(llvm::Module&) + 124
12 opt 0x0862c41b llvm::PassManager::run(llvm::Module&) + 39
13 opt 0x08306b36 main + 4373
14 libc.so.6 0xb7cc6455 __libc_start_main + 229
15 opt 0x082f5a51 __gxx_personality_v0 + 761
Stack dump:
0. Running pass 'CallGraph Pass Manager' on module ''.
Aborted

[llvmbot]

I applied your patch. rev. 68120.
Thanks!

[llvmbot]

mentioned in issue llvm/llvm-bugzilla-archive#33848

[llvmbot]

mentioned in issue llvm/llvm-bugzilla-archive#3601