[PATCH 141/144] add testcase for llvm segfault (issue #889)

[PATCH 141/144] add testcase for llvm segfault (issue #889)

The segmentation fault can be observed with llvm-10, llvm-11 and llvm-12
and seems to be fixed in llvm-13. It happens on the architectures armhf
and armel (both 32-bit) always and on x86_64 sporadically.
The test segfaults only on the first run (i.e. the kernel is not yet in
pocl's kernel cache) while it passes on subsequent execution (with
something already in the kernel cache), emitting only some llvm
diagnostics:

inlinable function call in a function with debug info must have a !dbg location
  %11 = call i32 @_Z12get_local_idj(i32 0)
inlinable function call in a function with debug info must have a !dbg location
  %19 = call i32 @_Z12get_local_idj(i32 1)
inlinable function call in a function with debug info must have a !dbg location
  %27 = call i32 @_Z12get_local_idj(i32 2)

The backtrace of the segmentation fault as observed with llvm-10 and pocl 1.6:
 #0  getEmissionKind () at .../llvm/include/llvm/IR/DebugInfoMetadata.h:1244
 #1  initialize () at .../llvm/lib/CodeGen/LexicalScopes.cpp:53
 #2  0xb14102f0 in computeIntervals () at .../llvm/lib/CodeGen/LiveDebugVariables.cpp:979
 #3  runOnMachineFunction () at .../llvm/lib/CodeGen/LiveDebugVariables.cpp:996
 #4  runOnMachineFunction () at .../llvm/lib/CodeGen/LiveDebugVariables.cpp:1023
 #5  0xb14856c8 in runOnFunction () at .../llvm/lib/CodeGen/MachineFunctionPass.cpp:73
 #6  0xb12ff494 in runOnFunction () at .../llvm/lib/IR/LegacyPassManager.cpp:1481
 #7  0xb12ff750 in runOnModule () at .../llvm/lib/IR/LegacyPassManager.cpp:1517
 #8  0xb12ffba8 in runOnModule () at .../llvm/lib/IR/LegacyPassManager.cpp:1582
 #9  run () at .../llvm/lib/IR/LegacyPassManager.cpp:1694
 #10 0xb6e64c82 in pocl_llvm_codegen (Device=Device@entry=0xdb0010, Modp=0x1361838, Output=Output@entry=0xbefde86c, OutputSize=OutputSize@entry=0xbefde880) at ./lib/CL/pocl_llvm_wg.cc:624
 #11 0xb6e291de in llvm_codegen (output=output@entry=0xdeb898 "...BMDHA/Sdot_kernel/0-0-0/Sdot_kernel.so", device_i=device_i@entry=0, kernel=kernel@entry=0xbefe0240,
     device=0xdb0010, command=command@entry=0xbefe0278, specialize=specialize@entry=0) at ./lib/CL/devices/common.c:158
 #12 0xb6e2ae44 in pocl_check_kernel_disk_cache (command=command@entry=0xbefe0278, specialized=specialized@entry=0) at ./lib/CL/devices/common.c:958
 #13 0xb6e2b262 in pocl_check_kernel_dlhandle_cache (command=0xbefe0278, initial_refcount=0, specialize=0) at ./lib/CL/devices/common.c:1081
 #14 0xb6e033d4 in program_compile_dynamic_wg_binaries (program=program@entry=0xd8ab88) at ./lib/CL/pocl_build.c:179
 #15 0xb6e13f20 in get_binary_sizes (sizes=0xbefe0384, program=0xd8ab88) at ./lib/CL/clGetProgramInfo.c:36
 #16 POclGetProgramInfo (program=0xd8ab88, param_name=4453, param_value_size=128, param_value=0xbefe0384, param_value_size_ret=0xbefe0380) at ./lib/CL/clGetProgramInfo.c:115
 #17 0x00473070 in main () at 975931.c:238

https://github.com/pocl/pocl/issues/889
https://bugs.debian.org/975931

Gbp-Pq: Name 0141-add-testcase-for-llvm-segfault-issue-889.patch