[MemProf] Pass down memory profile name with optional path from clang

Similar to -fprofile-generate=, add -fmemory-profile= which takes a directory path. This is passed down to LLVM via a new module flag metadata. LLVM in turn provides this name to the runtime via the new __memprof_profile_filename variable. Additionally, always pass a default filename (in $cwd if a directory name is not specified vi the = form of the option). This is also consistent with the behavior of the PGO instrumentation. Since the memory profiles will generally be fairly large, it doesn't make sense to dump them to stderr. Also, importantly, the memory profiles will eventually be dumped in a compact binary format, which is another reason why it does not make sense to send these to stderr by default. Change the existing memprof tests to specify log_path=stderr when that was being relied on. Depends on D89086. Differential Revision: https://reviews.llvm.org/D89087
llvm · Nov 2, 2020 · 0949f96 · 0949f96
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diff --git a/clang/include/clang/Basic/CodeGenOptions.def b/clang/include/clang/Basic/CodeGenOptions.def
@@ -151,7 +151,6 @@ CODEGENOPT(IncrementalLinkerCompatible, 1, 0) ///< Emit an object file which can
                                               ///< linker.
 CODEGENOPT(MergeAllConstants , 1, 1) ///< Merge identical constants.
 CODEGENOPT(MergeFunctions    , 1, 0) ///< Set when -fmerge-functions is enabled.
-CODEGENOPT(MemProf           , 1, 0) ///< Set when -fmemory-profile is enabled.
 CODEGENOPT(MSVolatile        , 1, 0) ///< Set when /volatile:ms is enabled.
 CODEGENOPT(NoCommon          , 1, 0) ///< Set when -fno-common or C++ is enabled.
 CODEGENOPT(NoDwarfDirectoryAsm , 1, 0) ///< Set when -fno-dwarf-directory-asm is

diff --git a/clang/include/clang/Basic/CodeGenOptions.h b/clang/include/clang/Basic/CodeGenOptions.h
@@ -231,6 +231,9 @@ class CodeGenOptions : public CodeGenOptionsBase {
   /// Name of the profile file to use with -fprofile-sample-use.
   std::string SampleProfileFile;
 
+  /// Name of the profile file to use as output for with -fmemory-profile.
+  std::string MemoryProfileOutput;
+
   /// Name of the profile file to use as input for -fprofile-instr-use
   std::string ProfileInstrumentUsePath;
 

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
@@ -1017,6 +1017,9 @@ def fsymbol_partition_EQ : Joined<["-"], "fsymbol-partition=">, Group<f_Group>,
   Flags<[CC1Option]>;
 
 defm memory_profile : OptInFFlag<"memory-profile", "Enable", "Disable", " heap memory profiling">;
+def fmemory_profile_EQ : Joined<["-"], "fmemory-profile=">,
+    Group<f_Group>, Flags<[CC1Option]>, MetaVarName<"<directory>">,
+    HelpText<"Enable heap memory profiling and dump results into <directory>">;
 
 // Begin sanitizer flags. These should all be core options exposed in all driver
 // modes.

diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
@@ -687,7 +687,7 @@ void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
   if (LangOpts.Coroutines)
     addCoroutinePassesToExtensionPoints(PMBuilder);
 
-  if (CodeGenOpts.MemProf) {
+  if (!CodeGenOpts.MemoryProfileOutput.empty()) {
     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
                            addMemProfilerPasses);
     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
@@ -1421,7 +1421,7 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
     if (CodeGenOpts.UniqueInternalLinkageNames)
       MPM.addPass(UniqueInternalLinkageNamesPass());
 
-    if (CodeGenOpts.MemProf) {
+    if (!CodeGenOpts.MemoryProfileOutput.empty()) {
       MPM.addPass(createModuleToFunctionPassAdaptor(MemProfilerPass()));
       MPM.addPass(ModuleMemProfilerPass());
     }

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -607,6 +607,13 @@ void CodeGenModule::Release() {
                               !LangOpts.isSignReturnAddressWithAKey());
   }
 
+  if (!CodeGenOpts.MemoryProfileOutput.empty()) {
+    llvm::LLVMContext &Ctx = TheModule.getContext();
+    getModule().addModuleFlag(
+        llvm::Module::Error, "MemProfProfileFilename",
+        llvm::MDString::get(Ctx, CodeGenOpts.MemoryProfileOutput));
+  }
+
   if (LangOpts.CUDAIsDevice && getTriple().isNVPTX()) {
     // Indicate whether __nvvm_reflect should be configured to flush denormal
     // floating point values to 0.  (This corresponds to its "__CUDA_FTZ"

diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
@@ -868,6 +868,7 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
                     D.CCCIsCXX();
 
   NeedsMemProfRt = Args.hasFlag(options::OPT_fmemory_profile,
+                                options::OPT_fmemory_profile_EQ,
                                 options::OPT_fno_memory_profile, false);
 
   // Finally, initialize the set of available and recoverable sanitizers.

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -4309,9 +4309,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   if (Args.getLastArg(options::OPT_save_temps_EQ))
     Args.AddLastArg(CmdArgs, options::OPT_save_temps_EQ);
 
-  if (Args.hasFlag(options::OPT_fmemory_profile,
-                   options::OPT_fno_memory_profile, false))
-    Args.AddLastArg(CmdArgs, options::OPT_fmemory_profile);
+  auto *MemProfArg = Args.getLastArg(options::OPT_fmemory_profile,
+                                     options::OPT_fmemory_profile_EQ,
+                                     options::OPT_fno_memory_profile);
+  if (MemProfArg &&
+      !MemProfArg->getOption().matches(options::OPT_fno_memory_profile))
+    MemProfArg->render(Args, CmdArgs);
 
   // Embed-bitcode option.
   // Only white-listed flags below are allowed to be embedded.

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1038,7 +1038,15 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.ThinLinkBitcodeFile =
       std::string(Args.getLastArgValue(OPT_fthin_link_bitcode_EQ));
 
-  Opts.MemProf = Args.hasArg(OPT_fmemory_profile);
+  // The memory profile runtime appends the pid to make this name more unique.
+  const char *MemProfileBasename = "memprof.profraw";
+  if (Args.hasArg(OPT_fmemory_profile_EQ)) {
+    SmallString<128> Path(
+        std::string(Args.getLastArgValue(OPT_fmemory_profile_EQ)));
+    llvm::sys::path::append(Path, MemProfileBasename);
+    Opts.MemoryProfileOutput = std::string(Path);
+  } else if (Args.hasArg(OPT_fmemory_profile))
+    Opts.MemoryProfileOutput = MemProfileBasename;
 
   Opts.MSVolatile = Args.hasArg(OPT_fms_volatile);
 

diff --git a/clang/test/CodeGen/memory-profile-filename.c b/clang/test/CodeGen/memory-profile-filename.c
@@ -0,0 +1,12 @@
+// Test that we get the expected module flag metadata for the memory profile
+// filename.
+// RUN: %clang -target x86_64-linux-gnu -S -emit-llvm -o - %s | FileCheck %s --check-prefix=NONE
+// RUN: %clang -target x86_64-linux-gnu -fmemory-profile -S -emit-llvm -o - %s | FileCheck %s --check-prefix=DEFAULTNAME
+// RUN: %clang -target x86_64-linux-gnu -fmemory-profile=/tmp -S -emit-llvm -o - %s | FileCheck %s --check-prefix=CUSTOMNAME
+int main(void) {
+  return 0;
+}
+
+// NONE-NOT: MemProfProfileFilename
+// DEFAULTNAME: !{i32 1, !"MemProfProfileFilename", !"memprof.profraw"}
+// CUSTOMNAME: !{i32 1, !"MemProfProfileFilename", !"/tmp/memprof.profraw"}
diff --git a/clang/test/Driver/fmemprof.cpp b/clang/test/Driver/fmemprof.cpp
@@ -1,6 +1,10 @@
 // RUN: %clangxx -target x86_64-linux-gnu -fmemory-profile %s -### 2>&1 | FileCheck %s
+// RUN: %clangxx -target x86_64-linux-gnu -fmemory-profile=foo %s -### 2>&1 | FileCheck %s --check-prefix=DIR
 // RUN: %clangxx -target x86_64-linux-gnu -fmemory-profile -fno-memory-profile %s -### 2>&1 | FileCheck %s --check-prefix=OFF
+// RUN: %clangxx -target x86_64-linux-gnu -fmemory-profile=foo -fno-memory-profile %s -### 2>&1 | FileCheck %s --check-prefix=OFF
 // CHECK: "-cc1" {{.*}} "-fmemory-profile"
 // CHECK: ld{{.*}}libclang_rt.memprof{{.*}}libclang_rt.memprof_cxx
+// DIR: "-cc1" {{.*}} "-fmemory-profile=foo"
+// DIR: ld{{.*}}libclang_rt.memprof{{.*}}libclang_rt.memprof_cxx
 // OFF-NOT: "-fmemory-profile"
 // OFF-NOT: libclang_rt.memprof
diff --git a/compiler-rt/test/memprof/TestCases/atexit_stats.cpp b/compiler-rt/test/memprof/TestCases/atexit_stats.cpp
@@ -1,8 +1,8 @@
 // Check atexit option.
 
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts=atexit=1 %run %t 2>&1 | FileCheck %s
-// RUN: %env_memprof_opts=atexit=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOATEXIT
+// RUN: %env_memprof_opts=log_path=stderr:atexit=1 %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:atexit=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOATEXIT
 
 // CHECK: MemProfiler exit stats:
 // CHECK: Stats: {{[0-9]+}}M malloced ({{[0-9]+}}M for overhead) by {{[0-9]+}} calls

diff --git a/compiler-rt/test/memprof/TestCases/dump_process_map.cpp b/compiler-rt/test/memprof/TestCases/dump_process_map.cpp
@@ -1,8 +1,8 @@
 // Check print_module_map option.
 
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts=print_module_map=1 %run %t 2>&1 | FileCheck %s
-// RUN: %env_memprof_opts=print_module_map=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOMAP
+// RUN: %env_memprof_opts=log_path=stderr:print_module_map=1 %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:print_module_map=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOMAP
 
 // CHECK: Process memory map follows:
 // CHECK: dump_process_map.cpp.tmp

diff --git a/compiler-rt/test/memprof/TestCases/log_path_test.cpp b/compiler-rt/test/memprof/TestCases/log_path_test.cpp
@@ -3,8 +3,8 @@
 //
 // RUN: %clangxx_memprof  %s -o %t
 
-// Regular run.
-// RUN: %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-GOOD --dump-input=always
+// stderr log_path
+// RUN: %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-GOOD --dump-input=always
 
 // Good log_path.
 // RUN: rm -f %t.log.*

diff --git a/compiler-rt/test/memprof/TestCases/malloc-size-too-big.cpp b/compiler-rt/test/memprof/TestCases/malloc-size-too-big.cpp
@@ -1,8 +1,8 @@
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts=allocator_may_return_null=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-SUMMARY
-// RUN: %env_memprof_opts=allocator_may_return_null=1 %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-NULL
+// RUN: %env_memprof_opts=log_path=stderr:allocator_may_return_null=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-SUMMARY
+// RUN: %env_memprof_opts=log_path=stderr:allocator_may_return_null=1 %run %t 2>&1 | FileCheck %s --check-prefix=CHECK-NULL
 // Test print_summary
-// RUN: %env_memprof_opts=allocator_may_return_null=0:print_summary=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-NOSUMMARY
+// RUN: %env_memprof_opts=log_path=stderr:allocator_may_return_null=0:print_summary=0 not %run %t 2>&1 | FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-NOSUMMARY
 
 #include <stdio.h>
 #include <stdlib.h>

diff --git a/compiler-rt/test/memprof/TestCases/mem_info_cache_entries.cpp b/compiler-rt/test/memprof/TestCases/mem_info_cache_entries.cpp
@@ -1,6 +1,6 @@
 // Check mem_info_cache_entries option.
 
-// RUN: %clangxx_memprof -O0 %s -o %t && %env_memprof_opts=mem_info_cache_entries=15:print_mem_info_cache_miss_rate=1:print_mem_info_cache_miss_rate_details=1 %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_memprof -O0 %s -o %t && %env_memprof_opts=log_path=stderr:mem_info_cache_entries=15:print_mem_info_cache_miss_rate=1:print_mem_info_cache_miss_rate_details=1 %run %t 2>&1 | FileCheck %s
 
 // CHECK: Set 14 miss rate: 0 / {{.*}} = 0.00%
 // CHECK-NOT: Set

diff --git a/compiler-rt/test/memprof/TestCases/print_miss_rate.cpp b/compiler-rt/test/memprof/TestCases/print_miss_rate.cpp
@@ -2,8 +2,8 @@
 // print_mem_info_cache_miss_rate_details options.
 
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts=print_mem_info_cache_miss_rate=1 %run %t 2>&1 | FileCheck %s
-// RUN: %env_memprof_opts=print_mem_info_cache_miss_rate=1:print_mem_info_cache_miss_rate_details=1 %run %t 2>&1 | FileCheck %s --check-prefix=DETAILS
+// RUN: %env_memprof_opts=log_path=stderr:print_mem_info_cache_miss_rate=1 %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:print_mem_info_cache_miss_rate=1:print_mem_info_cache_miss_rate_details=1 %run %t 2>&1 | FileCheck %s --check-prefix=DETAILS
 
 // CHECK: Overall miss rate: 0 / {{.*}} = 0.00%
 // DETAILS: Set 0 miss rate: 0 / {{.*}} = 0.00%

diff --git a/compiler-rt/test/memprof/TestCases/stress_dtls.c b/compiler-rt/test/memprof/TestCases/stress_dtls.c
@@ -7,9 +7,9 @@
 // RUN: %clangxx_memprof %s -ldl -pthread -o %t
 // RUN: %run %t 0 3
 // RUN: %run %t 2 3
-// RUN: %env_memprof_opts=verbosity=2 %run %t 10 2 2>&1 | FileCheck %s
-// RUN: %env_memprof_opts=verbosity=2:intercept_tls_get_addr=1 %run %t 10 2 2>&1 | FileCheck %s
-// RUN: %env_memprof_opts=verbosity=2:intercept_tls_get_addr=0 %run %t 10 2 2>&1 | FileCheck %s --check-prefix=CHECK0
+// RUN: %env_memprof_opts=log_path=stderr:verbosity=2 %run %t 10 2 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:verbosity=2:intercept_tls_get_addr=1 %run %t 10 2 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:verbosity=2:intercept_tls_get_addr=0 %run %t 10 2 2>&1 | FileCheck %s --check-prefix=CHECK0
 // CHECK: __tls_get_addr
 // CHECK: Creating thread 0
 // CHECK: __tls_get_addr

diff --git a/compiler-rt/test/memprof/TestCases/test_malloc_load_store.c b/compiler-rt/test/memprof/TestCases/test_malloc_load_store.c
@@ -3,10 +3,10 @@
 // before exit.
 
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts= %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // RUN: %clangxx_memprof -DFREE -O0 %s -o %t
-// RUN: %env_memprof_opts= %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // This is actually:
 //  Memory allocation stack id = STACKID

diff --git a/compiler-rt/test/memprof/TestCases/test_memintrin.cpp b/compiler-rt/test/memprof/TestCases/test_memintrin.cpp
@@ -1,6 +1,6 @@
 // Check profile with calls to memory intrinsics.
 
-// RUN: %clangxx_memprof -O0 %s -o %t && %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_memprof -O0 %s -o %t && %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // This is actually:
 //  Memory allocation stack id = STACKIDP

diff --git a/compiler-rt/test/memprof/TestCases/test_new_load_store.cpp b/compiler-rt/test/memprof/TestCases/test_new_load_store.cpp
@@ -3,14 +3,14 @@
 // before exit.
 
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts= %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // RUN: %clangxx_memprof -DFREE -O0 %s -o %t
-// RUN: %env_memprof_opts= %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // Try again with callbacks instead of inline sequences
 // RUN: %clangxx_memprof -mllvm -memprof-use-callbacks -O0 %s -o %t
-// RUN: %env_memprof_opts= %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // This is actually:
 //  Memory allocation stack id = STACKID

diff --git a/compiler-rt/test/memprof/TestCases/test_terse.cpp b/compiler-rt/test/memprof/TestCases/test_terse.cpp
@@ -3,10 +3,10 @@
 // deallocated before exit.
 
 // RUN: %clangxx_memprof -O0 %s -o %t
-// RUN: %env_memprof_opts=print_terse=1 %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:print_terse=1 %run %t 2>&1 | FileCheck %s
 
 // RUN: %clangxx_memprof -DFREE -O0 %s -o %t
-// RUN: %env_memprof_opts=print_terse=1 %run %t 2>&1 | FileCheck %s
+// RUN: %env_memprof_opts=log_path=stderr:print_terse=1 %run %t 2>&1 | FileCheck %s
 
 // CHECK: MIB:[[STACKID:[0-9]+]]/1/40.00/40/40/20.00/20/20/[[AVELIFETIME:[0-9]+]].00/[[AVELIFETIME]]/[[AVELIFETIME]]/0/0/0/0
 // CHECK: Stack for id [[STACKID]]:

diff --git a/compiler-rt/test/memprof/TestCases/unaligned_loads_and_stores.cpp b/compiler-rt/test/memprof/TestCases/unaligned_loads_and_stores.cpp
@@ -1,4 +1,4 @@
-// RUN: %clangxx_memprof -O0 %s -o %t && %run %t 2>&1 | FileCheck %s
+// RUN: %clangxx_memprof -O0 %s -o %t && %env_memprof_opts=log_path=stderr %run %t 2>&1 | FileCheck %s
 
 // This is actually:
 //  Memory allocation stack id = STACKID

diff --git a/llvm/lib/Transforms/Instrumentation/MemProfiler.cpp b/llvm/lib/Transforms/Instrumentation/MemProfiler.cpp
@@ -60,6 +60,8 @@ constexpr char MemProfVersionCheckNamePrefix[] =
 constexpr char MemProfShadowMemoryDynamicAddress[] =
     "__memprof_shadow_memory_dynamic_address";
 
+constexpr char MemProfFilenameVar[] = "__memprof_profile_filename";
+
 // Command-line flags.
 
 static cl::opt<bool> ClInsertVersionCheck(
@@ -486,6 +488,26 @@ void MemProfiler::instrumentAddress(Instruction *OrigIns,
   IRB.CreateStore(ShadowValue, ShadowAddr);
 }
 
+// Create the variable for the profile file name.
+void createProfileFileNameVar(Module &M) {
+  const MDString *MemProfFilename =
+      dyn_cast_or_null<MDString>(M.getModuleFlag("MemProfProfileFilename"));
+  if (!MemProfFilename)
+    return;
+  assert(!MemProfFilename->getString().empty() &&
+         "Unexpected MemProfProfileFilename metadata with empty string");
+  Constant *ProfileNameConst = ConstantDataArray::getString(
+      M.getContext(), MemProfFilename->getString(), true);
+  GlobalVariable *ProfileNameVar = new GlobalVariable(
+      M, ProfileNameConst->getType(), /*isConstant=*/true,
+      GlobalValue::WeakAnyLinkage, ProfileNameConst, MemProfFilenameVar);
+  Triple TT(M.getTargetTriple());
+  if (TT.supportsCOMDAT()) {
+    ProfileNameVar->setLinkage(GlobalValue::ExternalLinkage);
+    ProfileNameVar->setComdat(M.getOrInsertComdat(MemProfFilenameVar));
+  }
+}
+
 bool ModuleMemProfiler::instrumentModule(Module &M) {
   // Create a module constructor.
   std::string MemProfVersion = std::to_string(LLVM_MEM_PROFILER_VERSION);
@@ -500,6 +522,8 @@ bool ModuleMemProfiler::instrumentModule(Module &M) {
   const uint64_t Priority = getCtorAndDtorPriority(TargetTriple);
   appendToGlobalCtors(M, MemProfCtorFunction, Priority);
 
+  createProfileFileNameVar(M);
+
   return true;
 }
 

diff --git a/llvm/test/Instrumentation/HeapProfiler/filename.ll b/llvm/test/Instrumentation/HeapProfiler/filename.ll
@@ -0,0 +1,15 @@
+; Test to ensure that the filename provided by clang in the module flags
+; metadata results in the expected __memprof_profile_filename insertion.
+
+; RUN: opt < %s -mtriple=x86_64-unknown-linux -memprof -memprof-module -S | FileCheck --check-prefixes=CHECK %s
+
+define i32 @main() {
+entry:
+  ret i32 0
+}
+
+!llvm.module.flags = !{!0}
+!0 = !{i32 1, !"MemProfProfileFilename", !"/tmp/memprof.profraw"}
+
+; CHECK: $__memprof_profile_filename = comdat any
+; CHECK: @__memprof_profile_filename = constant [21 x i8] c"/tmp/memprof.profraw\00", comdat