[memprof] Add a test to verify callstack order.

We add to ensure that we are observing the correct callstack order in memprof
during symbolization. There was some confusion whether the order of
DIFrame objects were reversed but in reality the leaf function is at
index 0 so no code changes are required.

Differential Revision: https://reviews.llvm.org/D121759

llvm/lib/ProfileData/RawMemProfReader.cpp

@@ -327,6 +327,11 @@ Error RawMemProfReader::symbolizeAndFilterStackFrames() {
 
       for (size_t I = 0; I < DI.getNumberOfFrames(); I++) {
         const auto &Frame = DI.getFrame(I);
+        LLVM_DEBUG(
+            // Print out the name to guid mapping for debugging.
+            llvm::dbgs() << "FunctionName: " << Frame.FunctionName << " GUID: "
+                         << Function::getGUID(trimSuffix(Frame.FunctionName))
+                         << "\n";);
         SymbolizedFrame[VAddr].emplace_back(
             // We use the function guid which we expect to be a uint64_t. At
             // this time, it is the lower 64 bits of the md5 of the function

llvm/test/tools/llvm-profdata/memprof-inline.test

@@ -0,0 +1,106 @@
+REQUIRES: x86_64-linux
+
+The input raw profile test has been generated from the following source code:
+
+```
+#include <stdlib.h>
+#include <string.h>
+
+__attribute__((always_inline))
+void qux(int x) {
+  char *ptr = malloc(x);
+  memset(ptr, 0, x);
+  free(ptr);
+}
+
+__attribute__((noinline))
+void foo(int x){ qux(x); }
+
+__attribute__((noinline))
+void bar(int x) { foo(x); }
+
+int main(int argc, char **argv) {
+  bar(argc);
+  return 0;
+}
+```
+
+Compile and run with the following commands:
+
+```
+bin/clang -fuse-ld=lld -Wl,--no-rosegment -gmlt -fdebug-info-for-profiling \
+          -fmemory-profile -mno-omit-leaf-frame-pointer -fno-omit-frame-pointer \
+          -fno-optimize-sibling-calls -m64 -Wl,-build-id inline.c -o memprof-inline.exe
+
+env MEMPROF_OPTIONS=log_path=stdout ./memprof-inline.exe > inline.memprofraw
+```
+
+From a debug run we collect the name to guid mappings to ensure that the
+ordering we observe is as expected.
+
+```
+build-dbg/bin/llvm-profdata show --memory --debug-only=memprof \
+          inline.memprofraw --profiled-binary memprof-inline.exe
+
+FunctionName: qux GUID: 15505678318020221912
+FunctionName: foo GUID: 6699318081062747564
+FunctionName: bar GUID: 16434608426314478903
+FunctionName: main GUID: 15822663052811949562
+
+[..omit output here which is checked below..]
+```
+
+RUN: llvm-profdata show --memory %p/Inputs/inline.memprofraw --profiled-binary %p/Inputs/memprof-inline.exe
+
+CHECK:  MemprofProfile:
+CHECK-NEXT:  -
+CHECK-NEXT:  Header:
+CHECK-NEXT:    Version: 1
+CHECK-NEXT:    TotalSizeBytes: 880
+CHECK-NEXT:    NumSegments: 9
+CHECK-NEXT:    NumMibInfo: 2
+CHECK-NEXT:    NumStackOffsets: 2
+CHECK-NEXT:  Records:
+CHECK-NEXT:  -
+CHECK-NEXT:    Callstack:
+CHECK-NEXT:    -
+CHECK-NEXT:      Function: 15505678318020221912
+CHECK-NEXT:      LineOffset: 1
+CHECK-NEXT:      Column: 15
+CHECK-NEXT:      Inline: 0
+CHECK-NEXT:    -
+CHECK-NEXT:      Function: 6699318081062747564
+CHECK-NEXT:      LineOffset: 0
+CHECK-NEXT:      Column: 18
+CHECK-NEXT:      Inline: 1
+CHECK-NEXT:    -
+CHECK-NEXT:      Function: 16434608426314478903
+CHECK-NEXT:      LineOffset: 0
+CHECK-NEXT:      Column: 19
+CHECK-NEXT:      Inline: 0
+CHECK-NEXT:    -
+CHECK-NEXT:      Function: 15822663052811949562
+CHECK-NEXT:      LineOffset: 1
+CHECK-NEXT:      Column: 3
+CHECK-NEXT:      Inline: 0
+CHECK-NEXT:    MemInfoBlock:
+CHECK-NEXT:      AllocCount: 1
+CHECK-NEXT:      TotalAccessCount: 1
+CHECK-NEXT:      MinAccessCount: 1
+CHECK-NEXT:      MaxAccessCount: 1
+CHECK-NEXT:      TotalSize: 1
+CHECK-NEXT:      MinSize: 1
+CHECK-NEXT:      MaxSize: 1
+CHECK-NEXT:      AllocTimestamp: 894
+CHECK-NEXT:      DeallocTimestamp: 894
+CHECK-NEXT:      TotalLifetime: 0
+CHECK-NEXT:      MinLifetime: 0
+CHECK-NEXT:      MaxLifetime: 0
+CHECK-NEXT:      AllocCpuId: 23
+CHECK-NEXT:      DeallocCpuId: 23
+CHECK-NEXT:      NumMigratedCpu: 0
+CHECK-NEXT:      NumLifetimeOverlaps: 0
+CHECK-NEXT:      NumSameAllocCpu: 0
+CHECK-NEXT:      NumSameDeallocCpu: 0
+CHECK-NEXT:      DataTypeId: {{[0-9]+}}
+