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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 - clang crashes under -O3 in llvm-project/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:516: void {anonymous}::Formula::canonicalize(const llvm::Loop&): Assertion `!BaseRegs.empty() && "1*reg => reg, should not be needed."' failed."
href="https://bugs.llvm.org/show_bug.cgi?id=49697">49697</a>
</td>
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<tr>
<th>Summary</th>
<td>clang crashes under -O3 in llvm-project/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:516: void {anonymous}::Formula::canonicalize(const llvm::Loop&): Assertion `!BaseRegs.empty() && "1*reg => reg, should not be needed."' 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>normal
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Scalar Optimizations
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>haoxintu@gmail.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>Hi all.
Clang crashes on the valid code under -O3. Note that this issue only occurs in
the current trunk version of clang while released versions of clang handle it
well.
$cat small.c
#include <stdint.h>
int a;
int8_t b;
void c() {
for (b = 8; b <= 6;)
;
int d = -4;
while (d < 20) {
d += 5;
int e = 7;
do {
int f = 7;
a = b;
while (f--)
for (b = 20; b <= 30; b++) {
int8_t *g = &b;
(*g -= a) || 0 > g < g;
}
} while (e--);
}
}
$clang -w -O3 small.c
clang:
/home/haoxin/haoxin-data/dut-research/compilers/llvm-project/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp:516:
void {anonymous}::Formula::canonicalize(const llvm::Loop&): Assertion
`!BaseRegs.empty() && "1*reg => reg, should not be needed."' failed.
PLEASE submit a bug report to <a href="https://bugs.llvm.org/">https://bugs.llvm.org/</a> and include the crash
backtrace, preprocessed source, and associated run script.
Stack dump:
0. Program arguments: clang -w -c -O3 small.c
1. <eof> parser at end of file
2. Code generation
3. Running pass 'Function Pass Manager' on module 'small.c'.
4. Running pass 'Loop Pass Manager' on function '@c'
5. Running pass 'Loop Strength Reduction' on basic block '%for.body11.6.1'
#0 0x00005629c94918ac llvm::sys::PrintStackTrace(llvm::raw_ostream&, int)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x345f8ac)
#1 0x00005629c948f4e4 llvm::sys::RunSignalHandlers()
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x345d4e4)
#2 0x00005629c948f77b llvm::sys::CleanupOnSignal(unsigned long)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x345d77b)
#3 0x00005629c93ec738 CrashRecoverySignalHandler(int)
CrashRecoveryContext.cpp:0:0
#4 0x00007f6a94406980 __restore_rt
(/lib/x86_64-linux-gnu/libpthread.so.0+0x12980)
#5 0x00007f6a9302efb7 raise
/build/glibc-S9d2JN/glibc-2.27/signal/../sysdeps/unix/sysv/linux/raise.c:51:0
#6 0x00007f6a93030921 abort /build/glibc-S9d2JN/glibc-2.27/stdlib/abort.c:81:0
#7 0x00007f6a9302048a __assert_fail_base
/build/glibc-S9d2JN/glibc-2.27/assert/assert.c:89:0
#8 0x00007f6a93020502 (/lib/x86_64-linux-gnu/libc.so.6+0x30502)
#9 0x00005629c926a39a
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x323839a)
#10 0x00005629c9274c95 (anonymous
namespace)::LSRInstance::GenerateReassociationsImpl((anonymous
namespace)::LSRUse&, unsigned int, (anonymous namespace)::Formula const&,
unsigned int, unsigned long, bool) LoopStrengthReduce.cpp:0:0
#11 0x00005629c9274d6d (anonymous
namespace)::LSRInstance::GenerateReassociationsImpl((anonymous
namespace)::LSRUse&, unsigned int, (anonymous namespace)::Formula const&,
unsigned int, unsigned long, bool) LoopStrengthReduce.cpp:0:0
#12 0x00005629c927e57a (anonymous
namespace)::LSRInstance::GenerateAllReuseFormulae() LoopStrengthReduce.cpp:0:0
#13 0x00005629c9287652 (anonymous
namespace)::LSRInstance::LSRInstance(llvm::Loop*, llvm::IVUsers&,
llvm::ScalarEvolution&, llvm::DominatorTree&, llvm::LoopInfo&,
llvm::TargetTransformInfo const&, llvm::AssumptionCache&,
llvm::TargetLibraryInfo&, llvm::MemorySSAUpdater*) LoopStrengthReduce.cpp:0:0
#14 0x00005629c928a267 ReduceLoopStrength(llvm::Loop*, llvm::IVUsers&,
llvm::ScalarEvolution&, llvm::DominatorTree&, llvm::LoopInfo&,
llvm::TargetTransformInfo const&, llvm::AssumptionCache&,
llvm::TargetLibraryInfo&, llvm::MemorySSA*) LoopStrengthReduce.cpp:0:0
#15 0x00005629c928cdba (anonymous
namespace)::LoopStrengthReduce::runOnLoop(llvm::Loop*, llvm::LPPassManager&)
LoopStrengthReduce.cpp:0:0
#16 0x00005629c8521833 llvm::LPPassManager::runOnFunction(llvm::Function&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x24ef833)
#17 0x00005629c8c4eca4 llvm::FPPassManager::runOnFunction(llvm::Function&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x2c1cca4)
#18 0x00005629c8c4f7e9 llvm::FPPassManager::runOnModule(llvm::Module&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x2c1d7e9)
#19 0x00005629c8c4e5c1 llvm::legacy::PassManagerImpl::run(llvm::Module&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x2c1c5c1)
#20 0x00005629c975422b (anonymous
namespace)::EmitAssemblyHelper::EmitAssemblyWithNewPassManager(clang::BackendAction,
std::unique_ptr<llvm::raw_pwrite_stream,
std::default_delete<llvm::raw_pwrite_stream> >) BackendUtil.cpp:0:0
#21 0x00005629c97574f5 clang::EmitBackendOutput(clang::DiagnosticsEngine&,
clang::HeaderSearchOptions const&, clang::CodeGenOptions const&,
clang::TargetOptions const&, clang::LangOptions const&, llvm::DataLayout
const&, llvm::Module*, clang::BackendAction,
std::unique_ptr<llvm::raw_pwrite_stream,
std::default_delete<llvm::raw_pwrite_stream> >)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x37254f5)
#22 0x00005629ca3d3816
clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x43a1816)
#23 0x00005629caf38969 clang::ParseAST(clang::Sema&, bool, bool)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x4f06969)
#24 0x00005629ca3d25d8 clang::CodeGenAction::ExecuteAction()
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x43a05d8)
#25 0x00005629c9d60ab9 clang::FrontendAction::Execute()
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x3d2eab9)
#26 0x00005629c9cfe6f1
clang::CompilerInstance::ExecuteAction(clang::FrontendAction&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x3ccc6f1)
#27 0x00005629c9e28df0
clang::ExecuteCompilerInvocation(clang::CompilerInstance*)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x3df6df0)
#28 0x00005629c70800f4 cc1_main(llvm::ArrayRef<char const*>, char const*,
void*)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x104e0f4)
#29 0x00005629c707c657 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&)
driver.cpp:0:0
#30 0x00005629c9bb00a5 void llvm::function_ref<void
()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef>
<span class="quote">>, std::__cxx11::basic_string<char, std::char_traits<char>,</span >
std::allocator<char> >*, bool*) const::'lambda'()>(long) Job.cpp:0:0
#31 0x00005629c93ec8b2
llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x33ba8b2)
#32 0x00005629c9bb13ec
clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef>
<span class="quote">>, std::__cxx11::basic_string<char, std::char_traits<char>,</span >
std::allocator<char> >*, bool*) const (.part.186) Job.cpp:0:0
#33 0x00005629c9b89309
clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&,
clang::driver::Command const*&) const
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x3b57309)
#34 0x00005629c9b89de7
clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&,
llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&) const
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x3b57de7)
#35 0x00005629c9b92c49
clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&,
llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*> >&)
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x3b60c49)
#36 0x00005629c6faaf8e main
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0xf78f8e)
#37 0x00007f6a93011bf7 __libc_start_main
/build/glibc-S9d2JN/glibc-2.27/csu/../csu/libc-start.c:344:0
#38 0x00005629c707c0da _start
(/media/haoxin/SeagateData/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin/clang-13+0x104a0da)
clang-13: error: clang frontend command failed with exit code 134 (use -v to
see invocation)
clang version 13.0.0 (<a href="https://github.com/llvm/llvm-project">https://github.com/llvm/llvm-project</a>
613157dd67ddddc1bbb1e87236efd389358b281b)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir:
/home/haoxin/haoxin-data/dut-research/compilers/llvm-project/build-20210321/bin
clang-13: note: diagnostic msg:
********************
PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang-13: note: diagnostic msg: /tmp/small-d37230.c
clang-13: note: diagnostic msg: /tmp/small-d37230.sh
clang-13: note: diagnostic msg:
********************
Thanks,
Haoxin</pre>
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