SamplePGO - Sort samples by source location when emitting as text.

When dumping function samples or writing them out as text format, it
helps if the samples are emitted sorted by source location. The sorting
of the maps is a bit slow, so we only do it on demand.

llvm-svn: 253568

5 files changed, 47 insertions, 14 deletions

diff --git a/llvm/include/llvm/ProfileData/SampleProf.h b/llvm/include/llvm/ProfileData/SampleProf.h
index a8960cf7bc1..a7b22c73548 100644
--- a/llvm/include/llvm/ProfileData/SampleProf.h
+++ b/llvm/include/llvm/ProfileData/SampleProf.h
@@ -77,6 +77,10 @@ struct LineLocation {
   LineLocation(uint32_t L, uint32_t D) : LineOffset(L), Discriminator(D) {}
   void print(raw_ostream &OS) const;
   void dump() const;
+  bool operator<(const LineLocation &O) const {
+    return LineOffset < O.LineOffset ||
+           (LineOffset == O.LineOffset && Discriminator < O.Discriminator);
+  }
 
   uint32_t LineOffset;
   uint32_t Discriminator;
@@ -335,6 +339,29 @@ private:
 
 raw_ostream &operator<<(raw_ostream &OS, const FunctionSamples &FS);
 
+/// Sort a LocationT->SampleT map by LocationT.
+///
+/// It produces a sorted list of <LocationT, SampleT> records by ascending
+/// order of LocationT.
+template <class LocationT, class SampleT> class SampleSorter {
+public:
+  typedef detail::DenseMapPair<LocationT, SampleT> SamplesWithLoc;
+  typedef SmallVector<const SamplesWithLoc *, 20> SamplesWithLocList;
+
+  SampleSorter(const DenseMap<LocationT, SampleT> &Samples) {
+    for (const auto &I : Samples)
+      V.push_back(&I);
+    std::stable_sort(V.begin(), V.end(),
+                     [](const SamplesWithLoc *A, const SamplesWithLoc *B) {
+                       return A->first < B->first;
+                     });
+  }
+  const SamplesWithLocList &get() const { return V; }
+
+private:
+  SamplesWithLocList V;
+};
+
 } // end namespace sampleprof
 
 } // end namespace llvm
diff --git a/llvm/lib/ProfileData/SampleProf.cpp b/llvm/lib/ProfileData/SampleProf.cpp
index 3d75d230fb6..c376a8bbd98 100644
--- a/llvm/lib/ProfileData/SampleProf.cpp
+++ b/llvm/lib/ProfileData/SampleProf.cpp
@@ -108,15 +108,18 @@ void FunctionSamples::print(raw_ostream &OS, unsigned Indent) const {
   OS << TotalSamples << ", " << TotalHeadSamples << ", " << BodySamples.size()
      << " sampled lines\n";
 
-  for (const auto &SI : BodySamples) {
+  SampleSorter<LineLocation, SampleRecord> SortedBodySamples(BodySamples);
+  for (const auto &SI : SortedBodySamples.get()) {
     OS.indent(Indent);
-    OS << SI.first << ": " << SI.second;
+    OS << SI->first << ": " << SI->second;
   }
 
-  for (const auto &CS : CallsiteSamples) {
+  SampleSorter<CallsiteLocation, FunctionSamples> SortedCallsiteSamples(
+      CallsiteSamples);
+  for (const auto &CS : SortedCallsiteSamples.get()) {
     OS.indent(Indent);
-    OS << CS.first << ": ";
-    CS.second.print(OS, Indent + 2);
+    OS << CS->first << ": ";
+    CS->second.print(OS, Indent + 2);
   }
 }
 
diff --git a/llvm/lib/ProfileData/SampleProfWriter.cpp b/llvm/lib/ProfileData/SampleProfWriter.cpp
index b7f6db5eb33..c9f89233468 100644
--- a/llvm/lib/ProfileData/SampleProfWriter.cpp
+++ b/llvm/lib/ProfileData/SampleProfWriter.cpp
@@ -32,7 +32,7 @@ using namespace llvm;
 /// \brief Write samples to a text file.
 ///
 /// Note: it may be tempting to implement this in terms of
-/// FunctionSamples::dump().  Please don't.  The dump functionality is intended
+/// FunctionSamples::print().  Please don't.  The dump functionality is intended
 /// for debugging and has no specified form.
 ///
 /// The format used here is more structured and deliberate because
@@ -44,9 +44,10 @@ std::error_code SampleProfileWriterText::write(StringRef FName,
     OS << ":" << S.getHeadSamples();
   OS << "\n";
 
-  for (const auto &I : S.getBodySamples()) {
-    LineLocation Loc = I.first;
-    const SampleRecord &Sample = I.second;
+  SampleSorter<LineLocation, SampleRecord> SortedSamples(S.getBodySamples());
+  for (const auto &I : SortedSamples.get()) {
+    LineLocation Loc = I->first;
+    const SampleRecord &Sample = I->second;
     OS.indent(Indent + 1);
     if (Loc.Discriminator == 0)
       OS << Loc.LineOffset << ": ";
@@ -60,10 +61,12 @@ std::error_code SampleProfileWriterText::write(StringRef FName,
     OS << "\n";
   }
 
+  SampleSorter<CallsiteLocation, FunctionSamples> SortedCallsiteSamples(
+      S.getCallsiteSamples());
   Indent += 1;
-  for (const auto &I : S.getCallsiteSamples()) {
-    CallsiteLocation Loc = I.first;
-    const FunctionSamples &CalleeSamples = I.second;
+  for (const auto &I : SortedCallsiteSamples.get()) {
+    CallsiteLocation Loc = I->first;
+    const FunctionSamples &CalleeSamples = I->second;
     OS.indent(Indent);
     if (Loc.Discriminator == 0)
       OS << Loc.LineOffset << ": ";
diff --git a/llvm/test/tools/llvm-profdata/gcc-gcov-sample-profile.test b/llvm/test/tools/llvm-profdata/gcc-gcov-sample-profile.test
index 609569a8fe1..dbcc74e1284 100644
--- a/llvm/test/tools/llvm-profdata/gcc-gcov-sample-profile.test
+++ b/llvm/test/tools/llvm-profdata/gcc-gcov-sample-profile.test
@@ -11,8 +11,8 @@ RUN: llvm-profdata show --sample %p/Inputs/gcc-sample-profile.gcov | FileCheck %
 SHOW1: Function: main: 364084, 0, 6 sampled lines
 SHOW1: 2.3: inlined callee: _Z3fool: 243786, 0, 3 sampled lines
 SHOW1:   1.3: inlined callee: _Z3bari: 0, 0, 2 sampled lines
-SHOW1:   1.8: inlined callee: _Z3bari: 0, 0, 2 sampled lines
 SHOW1:   1.7: inlined callee: _Z3bari: 98558, 0, 2 sampled lines
+SHOW1:   1.8: inlined callee: _Z3bari: 0, 0, 2 sampled lines
 
 2- Convert the profile to text encoding and check that they are both
    identical.
diff --git a/llvm/test/tools/llvm-profdata/inline-samples.test b/llvm/test/tools/llvm-profdata/inline-samples.test
index 156dc15aeef..421f002da9f 100644
--- a/llvm/test/tools/llvm-profdata/inline-samples.test
+++ b/llvm/test/tools/llvm-profdata/inline-samples.test
@@ -10,9 +10,9 @@ RUN: llvm-profdata show --sample %t.profbin | FileCheck %s --check-prefix=SHOW1
 SHOW1: Function: main: 366846, 0, 6 sampled lines
 SHOW1: 2.3: inlined callee: _Z3fool: 246044, 0, 3 sampled lines
 SHOW1:   1.3: inlined callee: _Z3bari: 0, 0, 2 sampled lines
-SHOW1:   1.8: inlined callee: _Z3bari: 0, 0, 2 sampled lines
 SHOW1:   1.7: inlined callee: _Z3bari: 99492, 0, 2 sampled lines
 SHOW1:     1.2: 46732
+SHOW1:   1.8: inlined callee: _Z3bari: 0, 0, 2 sampled lines
 
 3- Convert the binary profile to text encoding and check that they are both
    identical.