[clang] Assertion `(!Is64Bit || isInt<32>((long long)FIOffset + Imm)) && "Requesting 64-bit offset in 32-bit immediate!"' failed

[ym-xie]

code:

static int i = 0;
int main(void) {
  char s[] = "t";
  extern int putchar(int);
  putchar(s[-2147483648]);
  return 0;
}

just crash on trunk with assertion enabled.
https://godbolt.org/z/YPhYYYTjz
Generated by fuzzing
I didn't find any similar issues.

Backtrace

clang: /root/llvm-project/llvm/lib/Target/X86/X86RegisterInfo.cpp:971: virtual bool llvm::X86RegisterInfo::eliminateFrameIndex(llvm::MachineBasicBlock::iterator, int, unsigned int, llvm::RegScavenger*) const: Assertion `(!Is64Bit || isInt<32>((long long)FIOffset + Imm)) && "Requesting 64-bit offset in 32-bit immediate!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/clang -gdwarf-4 -g -o /app/output.s -mllvm --x86-asm-syntax=intel -fno-verbose-asm -S --gcc-toolchain=/opt/compiler-explorer/gcc-snapshot -fcolor-diagnostics -fno-crash-diagnostics -x c -std=c2x -c <source>
1.	<eof> parser at end of file
2.	Code generation
3.	Running pass 'Function Pass Manager' on module '<source>'.
4.	Running pass 'Prologue/Epilogue Insertion & Frame Finalization' on function '@main'
 #0 0x0000000003c71738 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3c71738)
 #1 0x0000000003c6f444 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3c6f444)
 #2 0x0000000003bbc988 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #3 0x0000711bd5a42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x0000711bd5a969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #5 0x0000711bd5a42476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #6 0x0000711bd5a287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #7 0x0000711bd5a2871b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #8 0x0000711bd5a39e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
 #9 0x000000000263e262 llvm::X86RegisterInfo::eliminateFrameIndex(llvm::MachineInstrBundleIterator<llvm::MachineInstr, false>, int, unsigned int, llvm::RegScavenger*) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x263e262)
#10 0x000000000313391c (anonymous namespace)::PEI::runOnMachineFunction(llvm::MachineFunction&) PrologEpilogInserter.cpp:0:0
#11 0x0000000002fbd179 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
#12 0x00000000035c6cff llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x35c6cff)
#13 0x00000000035c70b1 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x35c70b1)
#14 0x00000000035c7951 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x35c7951)
#15 0x0000000003f285b2 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>, clang::BackendConsumer*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3f285b2)
#16 0x000000000460209e clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x460209e)
#17 0x000000000660f9cc clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x660f9cc)
#18 0x0000000004602478 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4602478)
#19 0x00000000048be799 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x48be799)
#20 0x0000000004840e2e clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4840e2e)
#21 0x00000000049abb8e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x49abb8e)
#22 0x0000000000ce93ef cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xce93ef)
#23 0x0000000000ce0e8a ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#24 0x0000000004647ae9 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::'lambda'()>(long) Job.cpp:0:0
#25 0x0000000003bbce34 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3bbce34)
#26 0x00000000046480df clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (.part.0) Job.cpp:0:0
#27 0x000000000460c1ed clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x460c1ed)
#28 0x000000000460d26e clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x460d26e)
#29 0x0000000004614d95 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4614d95)
#30 0x0000000000ce6233 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xce6233)
#31 0x0000000000bb2524 main (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xbb2524)
#32 0x0000711bd5a29d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#33 0x0000711bd5a29e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#34 0x0000000000ce0935 _start (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xce0935)
clang: error: clang frontend command failed with exit code 134 (use -v to see invocation)
Compiler returned: 134

[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: None (wxie7)

code: ```c static int i = 24; int main(void) { char s[] = "tuesday"; extern int putchar(int); while (i > 0) { putchar(s[-2147483648]); } return 0; } ``` crash clang https://godbolt.org/z/G177j5hYa Generated by fuzzing

[ym-xie]

code

int main(void) {
    char x[2147483647];
    x[-42] = '!';
}

https://godbolt.org/z/5Ynr6fccE
above code als crash

[abhishek-kaushik22]

Looking at the history of this assertion, it used to be

  int64_t Offset = FIOffset + Imm;
  if (!Is64Bit) {
    assert(isInt<32>((long long)FIOffset + Imm) &&
           "Requesting 64-bit offset in 32-bit immediate!");
  }

before it was changed to

assert((!Is64Bit || isInt<32>((long long)FIOffset + Imm)) &&
           "Requesting 64-bit offset in 32-bit immediate!");

Shouldn't it be assert(!Is64Bit && isInt<32>((long long)FIOffset + Imm))?

[RKSimon]

Shouldn't it be:

assert((Is64Bit || isInt<32>((long long)FIOffset + Imm)) &&
           "Requesting 64-bit offset in 32-bit immediate!");

We only want the assert testing isInt<> in the !Is64Bit case.

[RKSimon]

It appears we have 2 asserts in X86RegisterInfo.cpp which do the same thing

[RKSimon]

Actually maybe not: bc2ae1c8