[llvm-profdata] Add check for text profile formats and improve error reporting

Summary:
This change addresses two possible instances of user error / confusion when
merging sampled profile data.

Previously any input that didn't match the raw or processed instrumented format
would automatically be interpreted as instrumented profile text format data.
No error would be reported during the merge.

Example:
If foo-sampled.profdata and bar-sampled.profdata are binary sampled profiles:

Old behavior:
$ llvm-profdata merge foo-sampled.profdata bar-sampled.profdata -output foobar-sampled.profdata
$ llvm-profdata show -sample foobar-sampled.profdata
error: foobar-sampled.profdata:1: Expected 'mangled_name:NUM:NUM', found  lprofi

This change adds basic checks for valid input data when assuming text input.
It also makes error messages related to file format validity more specific about
the assumbed profile data type.

New behavior:
$ llvm-profdata merge foo-sampled.profdata bar-sampled.profdata -o foobar-sampled.profdata
error: foo.profdata: Unrecognized instrumentation profile encoding format
Perhaps you forgot to use the -sample option?

Reviewers: bogner, davidxl, dnovillo

Subscribers: davidxl, llvm-commits

Differential Revision: http://reviews.llvm.org/D14558

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252916 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 29 insertions, 13 deletions

diff --git a/tools/llvm-profdata/llvm-profdata.cpp b/tools/llvm-profdata/llvm-profdata.cpp
index 48fc83c6971..1cd47dd5e84 100644
--- a/tools/llvm-profdata/llvm-profdata.cpp
+++ b/tools/llvm-profdata/llvm-profdata.cpp
@@ -29,16 +29,32 @@
 
 using namespace llvm;
 
-static void exitWithError(const Twine &Message, StringRef Whence = "") {
+static void exitWithError(const Twine &Message,
+                          StringRef Whence = "",
+                          StringRef Hint = "") {
   errs() << "error: ";
   if (!Whence.empty())
     errs() << Whence << ": ";
   errs() << Message << "\n";
+  if (!Hint.empty())
+    errs() << Hint << "\n";
   ::exit(1);
 }
 
+static void exitWithErrorCode(const std::error_code &Error, StringRef Whence = "") {
+  if (Error.category() == instrprof_category()) {
+    instrprof_error instrError = static_cast<instrprof_error>(Error.value());
+    if (instrError == instrprof_error::unrecognized_format) {
+      // Hint for common error of forgetting -sample for sample profiles.
+      exitWithError(Error.message(), Whence,
+                    "Perhaps you forgot to use the -sample option?");
+    }
+  }
+  exitWithError(Error.message(), Whence);
+}
+
 namespace {
-enum ProfileKinds { instr, sample };
+    enum ProfileKinds { instr, sample };
 }
 
 static void mergeInstrProfile(const cl::list<std::string> &Inputs,
@@ -49,20 +65,20 @@ static void mergeInstrProfile(const cl::list<std::string> &Inputs,
   std::error_code EC;
   raw_fd_ostream Output(OutputFilename.data(), EC, sys::fs::F_None);
   if (EC)
-    exitWithError(EC.message(), OutputFilename);
+    exitWithErrorCode(EC, OutputFilename);
 
   InstrProfWriter Writer;
   for (const auto &Filename : Inputs) {
     auto ReaderOrErr = InstrProfReader::create(Filename);
     if (std::error_code ec = ReaderOrErr.getError())
-      exitWithError(ec.message(), Filename);
+      exitWithErrorCode(ec, Filename);
 
     auto Reader = std::move(ReaderOrErr.get());
     for (auto &I : *Reader)
       if (std::error_code EC = Writer.addRecord(std::move(I)))
         errs() << Filename << ": " << I.Name << ": " << EC.message() << "\n";
     if (Reader->hasError())
-      exitWithError(Reader->getError().message(), Filename);
+      exitWithErrorCode(Reader->getError(), Filename);
   }
   Writer.write(Output);
 }
@@ -73,7 +89,7 @@ static void mergeSampleProfile(const cl::list<std::string> &Inputs,
   using namespace sampleprof;
   auto WriterOrErr = SampleProfileWriter::create(OutputFilename, OutputFormat);
   if (std::error_code EC = WriterOrErr.getError())
-    exitWithError(EC.message(), OutputFilename);
+    exitWithErrorCode(EC, OutputFilename);
 
   auto Writer = std::move(WriterOrErr.get());
   StringMap<FunctionSamples> ProfileMap;
@@ -82,7 +98,7 @@ static void mergeSampleProfile(const cl::list<std::string> &Inputs,
     auto ReaderOrErr =
         SampleProfileReader::create(Filename, getGlobalContext());
     if (std::error_code EC = ReaderOrErr.getError())
-      exitWithError(EC.message(), Filename);
+      exitWithErrorCode(EC, Filename);
 
     // We need to keep the readers around until after all the files are
     // read so that we do not lose the function names stored in each
@@ -91,7 +107,7 @@ static void mergeSampleProfile(const cl::list<std::string> &Inputs,
     Readers.push_back(std::move(ReaderOrErr.get()));
     const auto Reader = Readers.back().get();
     if (std::error_code EC = Reader->read())
-      exitWithError(EC.message(), Filename);
+      exitWithErrorCode(EC, Filename);
 
     StringMap<FunctionSamples> &Profiles = Reader->getProfiles();
     for (StringMap<FunctionSamples>::iterator I = Profiles.begin(),
@@ -143,7 +159,7 @@ static int showInstrProfile(std::string Filename, bool ShowCounts,
                             std::string ShowFunction, raw_fd_ostream &OS) {
   auto ReaderOrErr = InstrProfReader::create(Filename);
   if (std::error_code EC = ReaderOrErr.getError())
-    exitWithError(EC.message(), Filename);
+    exitWithErrorCode(EC, Filename);
 
   auto Reader = std::move(ReaderOrErr.get());
   uint64_t MaxFunctionCount = 0, MaxBlockCount = 0;
@@ -198,7 +214,7 @@ static int showInstrProfile(std::string Filename, bool ShowCounts,
     }
   }
   if (Reader->hasError())
-    exitWithError(Reader->getError().message(), Filename);
+    exitWithErrorCode(Reader->getError(), Filename);
 
   if (ShowAllFunctions || !ShowFunction.empty())
     OS << "Functions shown: " << ShownFunctions << "\n";
@@ -214,11 +230,11 @@ static int showSampleProfile(std::string Filename, bool ShowCounts,
   using namespace sampleprof;
   auto ReaderOrErr = SampleProfileReader::create(Filename, getGlobalContext());
   if (std::error_code EC = ReaderOrErr.getError())
-    exitWithError(EC.message(), Filename);
+    exitWithErrorCode(EC, Filename);
 
   auto Reader = std::move(ReaderOrErr.get());
   if (std::error_code EC = Reader->read())
-    exitWithError(EC.message(), Filename);
+    exitWithErrorCode(EC, Filename);
 
   if (ShowAllFunctions || ShowFunction.empty())
     Reader->dump(OS);
@@ -259,7 +275,7 @@ static int show_main(int argc, const char *argv[]) {
   std::error_code EC;
   raw_fd_ostream OS(OutputFilename.data(), EC, sys::fs::F_Text);
   if (EC)
-    exitWithError(EC.message(), OutputFilename);
+      exitWithErrorCode(EC, OutputFilename);
 
   if (ShowAllFunctions && !ShowFunction.empty())
     errs() << "warning: -function argument ignored: showing all functions\n";