[PATCH] D17361: [PGO] Add support to enable testing multiple supported targets

Mon Feb 22 11:55:30 PST 2016

On Mon, Feb 22, 2016 at 11:37 AM, Vedant Kumar <vsk at apple.com> wrote:
> vsk added a comment.
>
> Hi David,
>
> This commit enables tests on 64-bit Darwin which have apparently been failing. I now see:
>
>   ******************** TEST 'Profile-i386 :: instrprof-basic.c' FAILED ********************
>   Script:
>   --
>   /Users/vk/Desktop/llvm/Debug+Asserts/./bin/clang -arch i386  -fprofile-instr-generate -o /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp -O3 /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-basic.c
>   env LLVM_PROFILE_FILE=/Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp.profraw  /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp
>   llvm-profdata merge -o /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp.profdata /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp.profraw
>   /Users/vk/Desktop/llvm/Debug+Asserts/./bin/clang -arch i386  -fprofile-instr-use=/Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp.profdata -o - -S -emit-llvm /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-basic.c | FileCheck /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-basic.c
>   --
>   Exit Code: 139
>
>   Command Output (stderr):
>   --
>   /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.script: line 4: 20417 Segmentation fault: 11  env LLVM_PROFILE_FILE=/Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp.profraw /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-basic.c.tmp
>
> The segmentation fault is in `__llvm_profile_gather_value_data()`. Accessing `I->Values` dereferences `0x1`:
>
>   (lldb) p *I
>   (__llvm_profile_data) $11 = {
>     NameRef = 10864
>     FuncHash = 48378511633216
>     CounterPtr = 0x00000000
>     FunctionPointer = 0x0000df1e
>     Values = 0x00000001
>     NumCounters = 0
>     NumValueSites = ([0] = 13723)
>   }
>

Looks like the prof data iterator is returning some garbage entry. For
that test, it should have only 3 entries.  If it iterates more
entries, it is likely a linker bug on darwin.

> There's a second issue with corrupt raw profiles:
>
>   ********************
>   FAIL: Profile-i386 :: instrprof-without-libc.c (39 of 96)
>   ******************** TEST 'Profile-i386 :: instrprof-without-libc.c' FAILED ********************
>   Script:
>   --
>   /Users/vk/Desktop/llvm/Debug+Asserts/./bin/clang -arch i386  -fprofile-instr-generate -DCHECK_SYMBOLS -O3 -o /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.symbols /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-without-libc.c
>   llvm-nm /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.symbols | FileCheck /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-without-libc.c --check-prefix=CHECK-SYMBOLS
>   /Users/vk/Desktop/llvm/Debug+Asserts/./bin/clang -arch i386  -fprofile-instr-generate -O3 -o /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-without-libc.c
>   /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.profraw
>   llvm-profdata merge -o /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.profdata /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.profraw
>   /Users/vk/Desktop/llvm/Debug+Asserts/./bin/clang -arch i386  -fprofile-instr-use=/Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.profdata -o - -S -emit-llvm /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-without-libc.c | FileCheck /Users/vk/Desktop/llvm/projects/compiler-rt/test/profile/instrprof-without-libc.c
>   --
>   Exit Code: 1
>
>   Command Output (stderr):
>   --
>   error: /Users/vk/Desktop/llvm/build/projects/compiler-rt/test/profile/Profile-i386/Output/instrprof-without-libc.c.tmp.profraw: Invalid instrumentation profile data (file header is corrupt)
>
> This happens because `ProfileSize = 34359738544` (pretty close to 32 GB, which seems wrong):
>
>       frame #0: 0x00000001001fa851 llvm-profdata`llvm::RawInstrProfReader<unsigned int>::readHeader(this=0x0000000100b00000, Header=0x0000000100a00110) + 801 at InstrProfReader.cpp:337
>      334
>      335          auto *Start = reinterpret_cast<const char *>(&Header);
>      336          if (Start + ProfileSize > DataBuffer->getBufferEnd())
>   -> 337            return error(instrprof_error::bad_header);
>

It is likely that ValueDataSize in the header has bogus value. It is
likely related to the bug above -- some bogus function prof data entry
gets processed.

> I don't know if this last issue is affected by this commit, but I'm not sure why these tests are unsupported (they don't seem Linux-specific):

Looks like i386/darwin was never tested before? This just exposed some
latent bug.

thanks,

David

>
>   UNSUPPORTED: Profile-x86_64 :: Linux/coverage_ctors.cpp (1 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/coverage_dtor.cpp (2 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/instrprof-basic.c (3 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/coverage_test.cpp (4 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/coverage_shared.test (5 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/instrprof-comdat.test (6 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/instrprof-dlopen.test (7 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/instrprof-dynamic-one-shared.test (8 of 32)
>   UNSUPPORTED: Profile-x86_64 :: Linux/instrprof-dynamic-two-shared.test (9 of 32)
>
> For reference, I configure llvm with: `-DCMAKE_CROSSCOMPILING=False -DLLVM_TARGET_ARCH="X86" -DLLVM_TARGETS_TO_BUILD="X86;AArch64;ARM" -DCMAKE_BUILD_TYPE:STRING=Debug -DLLVM_ENABLE_ASSERTIONS=True -DLLVM_INCLUDE_TESTS=True -DLLVM_ENABLE_WARNINGS=False -G 'Ninja' ../`.
>
> AFAICT (checking -###), the compiler is grabbing the correct copy of compiler-rt and it has the right slice:
>
>   $ ninja check-profile [...]
>   $ file "/Users/vk/Desktop/llvm/build/bin/../lib/clang/3.9.0/lib/darwin/libclang_rt.profile_osx.a"
>   /Users/vk/Desktop/llvm/build/bin/../lib/clang/3.9.0/lib/darwin/libclang_rt.profile_osx.a: Mach-O universal binary with 3 architectures: [i386: current ar archive random library] [x86_64: current ar archive random library] [x86_64h: current ar archive random library]
>   /Users/vk/Desktop/llvm/build/bin/../lib/clang/3.9.0/lib/darwin/libclang_rt.profile_osx.a (for architecture i386):     current ar archive random library
>   /Users/vk/Desktop/llvm/build/bin/../lib/clang/3.9.0/lib/darwin/libclang_rt.profile_osx.a (for architecture x86_64):   current ar archive random library
>   /Users/vk/Desktop/llvm/build/bin/../lib/clang/3.9.0/lib/darwin/libclang_rt.profile_osx.a (for architecture x86_64h):  current ar archive random library
>
> I'll try to get to the bottom of this, but any help is appreciated.
>
>
> Repository:
>   rL LLVM
>
> http://reviews.llvm.org/D17361
>
>
>