Assertion `I != r2iMap_.end() && "Interval does not exist for register"' failed when -fcatch-undefined-behavior is used

[regehr]

Bugzilla Link	8989
Resolution	FIXED
Resolved on	Jan 20, 2011 00:20
Version	trunk
OS	Linux
CC	@stoklund

Extended Description

regehr@home:~/volatile/bugs/tmp345$ clang -c -O1 -fcatch-undefined-behavior small.c -w
clang: /mnt/z/z/compiler-build/llvm-r123579/include/llvm/CodeGen/LiveIntervalAnalysis.h:96: llvm::LiveInterval& llvm::LiveIntervals::getInterval(unsigned int): Assertion `I != r2iMap_.end() && "Interval does not exist for register"' failed.
0 clang 0x09492668
Stack dump:
0. Program arguments: /mnt/z/z/compiler-install/llvm-gcc-r123579-install/bin/clang -cc1 -triple i386-pc-linux-gnu -emit-obj -disable-free -main-file-name small.c -mrelocation-model static -mdisable-fp-elim -masm-verbose -mconstructor-aliases -target-cpu pentium4 -target-linker-version 2.20.51 -resource-dir /mnt/z/z/compiler-install/llvm-gcc-r123579-install/bin/../lib/clang/2.9 -O1 -w -ferror-limit 19 -fmessage-length 80 -fcatch-undefined-behavior -fgnu-runtime -fdiagnostics-show-option -fcolor-diagnostics -o small.o -x c small.c

1. parser at end of file
2. Code generation
3. Running pass 'Function Pass Manager' on module 'small.c'.
4. Running pass 'Simple Register Coalescing' on function '@func_39'
   clang: error: unable to execute command: Aborted
   clang: error: clang frontend command failed due to signal 1 (use -v to see invocation)

regehr@home:~/volatile/bugs/tmp345$ clang -v

clang version 2.9 (trunk 123579)
Target: i386-pc-linux-gnu
Thread model: posix

regehr@home:~/volatile/bugs/tmp345$ cat small.c

struct S0
{
int f1;
int f3;
unsigned char f5;
};

int safe (int);

struct S0 func_39 (const int * p_40, int * p_41,
int * const const uint32p_43)
{
unsigned char l_46[1][10];
if (safe (0))
{
}
else
{
struct S0 l_60 = {
1L, 8L
};
if (*p_40)
return l_60;
else
for (l_60.f5 = 0; l_60.f5 < 1; l_60.f5 += 1)
for (l_60.f1 = 0; l_60.f1 < 1; l_60.f1 += 1)
l_46[l_60.f5][l_60.f1];
}
struct S0 l_60 = {
1L, 8L
};
return l_60;
}

[stoklund]

Reduced bitcode file
llc bugpoint-reduced-simplified.bc
Assertion failed: (I != r2iMap_.end() && "Interval does not exist for register"), function getInterval, file /Volumes/Krask/g/llvm/include/llvm/CodeGen/LiveIntervalAnalysis.h, line 96.
0 llc 0x009c14c8 PrintStackTrace(void*) + 40
1 llc 0x009c1aaa SignalHandler(int) + 826
2 libSystem.B.dylib 0x95c5246b _sigtramp + 43
3 libSystem.B.dylib 0xffffffff _sigtramp + 1782242239
4 llc 0x0001f7fb abort + 27
5 llc 0x0001f7d4 __assert_rtn + 100
6 llc 0x006d478f llvm::LiveIntervals::getInterval(unsigned int) + 287
7 llc 0x00711560 llvm::SimpleRegisterCoalescing::runOnMachineFunction(llvm::MachineFunction&) + 2944
8 llc 0x0066b305 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) + 69
9 llc 0x009138b0 llvm::FPPassManager::runOnFunction(llvm::Function&) + 320
10 llc 0x00913c0c llvm::FPPassManager::runOnModule(llvm::Module&) + 76
11 llc 0x00913d54 llvm::MPPassManager::runOnModule(llvm::Module&) + 276
12 llc 0x0091437e llvm::PassManagerImpl::run(llvm::Module&) + 222
13 llc 0x0091496b llvm::PassManager::run(llvm::Module&) + 27
14 llc 0x000216df main + 4815
15 llc 0x00020405 start + 53
Stack dump:
0. Program arguments: Release+Asserts/bin/llc bugpoint-reduced-simplified.bc

1. Running pass 'Function Pass Manager' on module 'bugpoint-reduced-simplified.bc'.
2. Running pass 'Simple Register Coalescing' on function '@func_39'
   Illegal instruction

[stoklund]

Fixed in r123891. Thanks!