llvm-cov: Implement --no-output

In gcov, there's a -n/--no-output option, which disables the writing
of any .gcov files, so that it emits only the summary info on stdout.
This implements the same behaviour in llvm-cov.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208148 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 66 insertions, 22 deletions

diff --git a/include/llvm/Support/GCOV.h b/include/llvm/Support/GCOV.h
index 923affcd0b..267693fa49 100644
--- a/include/llvm/Support/GCOV.h
+++ b/include/llvm/Support/GCOV.h
@@ -37,9 +37,9 @@ namespace GCOV {
 
 /// GCOVOptions - A struct for passing gcov options between functions.
 struct GCOVOptions {
-  GCOVOptions(bool A, bool B, bool C, bool F, bool P, bool U, bool L)
+  GCOVOptions(bool A, bool B, bool C, bool F, bool P, bool U, bool L, bool N)
       : AllBlocks(A), BranchInfo(B), BranchCount(C), FuncCoverage(F),
-        PreservePaths(P), UncondBranch(U), LongFileNames(L) {}
+        PreservePaths(P), UncondBranch(U), LongFileNames(L), NoOutput(N) {}
 
   bool AllBlocks;
   bool BranchInfo;
@@ -48,6 +48,7 @@ struct GCOVOptions {
   bool PreservePaths;
   bool UncondBranch;
   bool LongFileNames;
+  bool NoOutput;
 };
 
 /// GCOVBuffer - A wrapper around MemoryBuffer to provide GCOV specific
@@ -389,13 +390,15 @@ public:
   void print(StringRef MainFilename, StringRef GCNOFile, StringRef GCDAFile);
 
 private:
-  void printFunctionSummary(raw_fd_ostream &OS,
+  std::string getCoveragePath(StringRef Filename, StringRef MainFilename);
+  std::unique_ptr<raw_ostream> openCoveragePath(StringRef CoveragePath);
+  void printFunctionSummary(raw_ostream &OS,
                             const FunctionVector &Funcs) const;
-  void printBlockInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
+  void printBlockInfo(raw_ostream &OS, const GCOVBlock &Block,
                       uint32_t LineIndex, uint32_t &BlockNo) const;
-  void printBranchInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
+  void printBranchInfo(raw_ostream &OS, const GCOVBlock &Block,
                        GCOVCoverage &Coverage, uint32_t &EdgeNo);
-  void printUncondBranchInfo(raw_fd_ostream &OS, uint32_t &EdgeNo,
+  void printUncondBranchInfo(raw_ostream &OS, uint32_t &EdgeNo,
                              uint64_t Count) const;
 
   void printCoverage(const GCOVCoverage &Coverage) const;
diff --git a/lib/IR/GCOV.cpp b/lib/IR/GCOV.cpp
index 522716309a..05fe1e07df 100644
--- a/lib/IR/GCOV.cpp
+++ b/lib/IR/GCOV.cpp
@@ -467,6 +467,38 @@ static std::string mangleCoveragePath(StringRef Filename, bool PreservePaths) {
   return Result.str();
 }
 
+std::string FileInfo::getCoveragePath(StringRef Filename,
+                                      StringRef MainFilename) {
+  if (Options.NoOutput)
+    // This is probably a bug in gcov, but when -n is specified, paths aren't
+    // mangled at all, and the -l and -p options are ignored. Here, we do the
+    // same.
+    return Filename;
+
+  std::string CoveragePath;
+  if (Options.LongFileNames && !Filename.equals(MainFilename))
+    CoveragePath =
+        mangleCoveragePath(MainFilename, Options.PreservePaths) + "##";
+  CoveragePath +=
+      mangleCoveragePath(Filename, Options.PreservePaths) + ".gcov";
+  return CoveragePath;
+}
+
+std::unique_ptr<raw_ostream>
+FileInfo::openCoveragePath(StringRef CoveragePath) {
+  if (Options.NoOutput)
+    return make_unique<raw_null_ostream>();
+
+  std::string ErrorInfo;
+  auto OS = make_unique<raw_fd_ostream>(CoveragePath.str().c_str(), ErrorInfo,
+                                        sys::fs::F_Text);
+  if (!ErrorInfo.empty()) {
+    errs() << ErrorInfo << "\n";
+    return make_unique<raw_null_ostream>();
+  }
+  return std::move(OS);
+}
+
 /// print -  Print source files with collected line count information.
 void FileInfo::print(StringRef MainFilename, StringRef GCNOFile,
                      StringRef GCDAFile) {
@@ -480,16 +512,9 @@ void FileInfo::print(StringRef MainFilename, StringRef GCNOFile,
     }
     StringRef AllLines = Buff->getBuffer();
 
-    std::string CoveragePath;
-    if (Options.LongFileNames && !Filename.equals(MainFilename))
-      CoveragePath =
-          mangleCoveragePath(MainFilename, Options.PreservePaths) + "##";
-    CoveragePath +=
-        mangleCoveragePath(Filename, Options.PreservePaths) + ".gcov";
-    std::string ErrorInfo;
-    raw_fd_ostream OS(CoveragePath.c_str(), ErrorInfo, sys::fs::F_Text);
-    if (!ErrorInfo.empty())
-      errs() << ErrorInfo << "\n";
+    std::string CoveragePath = getCoveragePath(Filename, MainFilename);
+    std::unique_ptr<raw_ostream> S = openCoveragePath(CoveragePath);
+    raw_ostream &OS = *S;
 
     OS << "        -:    0:Source:" << Filename << "\n";
     OS << "        -:    0:Graph:" << GCNOFile << "\n";
@@ -606,10 +631,11 @@ void FileInfo::print(StringRef MainFilename, StringRef GCNOFile,
   if (Options.FuncCoverage)
     printFuncCoverage();
   printFileCoverage();
+  return;
 }
 
 /// printFunctionSummary - Print function and block summary.
-void FileInfo::printFunctionSummary(raw_fd_ostream &OS,
+void FileInfo::printFunctionSummary(raw_ostream &OS,
                                     const FunctionVector &Funcs) const {
   for (FunctionVector::const_iterator I = Funcs.begin(), E = Funcs.end();
          I != E; ++I) {
@@ -631,7 +657,7 @@ void FileInfo::printFunctionSummary(raw_fd_ostream &OS,
 }
 
 /// printBlockInfo - Output counts for each block.
-void FileInfo::printBlockInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
+void FileInfo::printBlockInfo(raw_ostream &OS, const GCOVBlock &Block,
                               uint32_t LineIndex, uint32_t &BlockNo) const {
   if (Block.getCount() == 0)
     OS << "    $$$$$:";
@@ -641,7 +667,7 @@ void FileInfo::printBlockInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
 }
 
 /// printBranchInfo - Print conditional branch probabilities.
-void FileInfo::printBranchInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
+void FileInfo::printBranchInfo(raw_ostream &OS, const GCOVBlock &Block,
                                GCOVCoverage &Coverage, uint32_t &EdgeNo) {
   SmallVector<uint64_t, 16> BranchCounts;
   uint64_t TotalCounts = 0;
@@ -671,7 +697,7 @@ void FileInfo::printBranchInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
 }
 
 /// printUncondBranchInfo - Print unconditional branch probabilities.
-void FileInfo::printUncondBranchInfo(raw_fd_ostream &OS, uint32_t &EdgeNo,
+void FileInfo::printUncondBranchInfo(raw_ostream &OS, uint32_t &EdgeNo,
                                      uint64_t Count) const {
   OS << format("unconditional %2u ", EdgeNo++)
      << formatBranchInfo(Options, Count, Count) << "\n";
@@ -717,6 +743,8 @@ void FileInfo::printFileCoverage() const {
     const GCOVCoverage &Coverage = I->second;
     outs() << "File '" << Coverage.Name << "'\n";
     printCoverage(Coverage);
-    outs() << Coverage.Name << ":creating '" << Filename << "'\n\n";
+    if (!Options.NoOutput)
+      outs() << Coverage.Name << ":creating '" << Filename << "'\n";
+    outs() << "\n";
   }
 }
diff --git a/test/tools/llvm-cov/Inputs/test_no_output.output b/test/tools/llvm-cov/Inputs/test_no_output.output
new file mode 100644
index 0000000000..74286b9a2f
--- /dev/null
+++ b/test/tools/llvm-cov/Inputs/test_no_output.output
@@ -0,0 +1,6 @@
+File 'test.cpp'
+Lines executed:84.21% of 38
+
+File './test.h'
+Lines executed:100.00% of 1
+
diff --git a/test/tools/llvm-cov/llvm-cov.test b/test/tools/llvm-cov/llvm-cov.test
index 8457aef292..8f57d9a189 100644
--- a/test/tools/llvm-cov/llvm-cov.test
+++ b/test/tools/llvm-cov/llvm-cov.test
@@ -31,6 +31,9 @@ RUN: llvm-cov -o objdir/test test.c | diff -u test_no_options.output -
 RUN: diff -aub test_objdir.cpp.gcov test.cpp.gcov
 RUN: diff -aub test_objdir.h.gcov test.h.gcov
 
+# With gcov output disabled
+RUN: llvm-cov -n test.c | diff -u test_no_output.output -
+
 # Preserve paths. This mangles the output filenames.
 RUN: mkdir -p %t/srcdir/nested_dir
 RUN: cp test.cpp test.h %t/srcdir
diff --git a/tools/llvm-cov/llvm-cov.cpp b/tools/llvm-cov/llvm-cov.cpp
index 02f4b72216..9463609ae3 100644
--- a/tools/llvm-cov/llvm-cov.cpp
+++ b/tools/llvm-cov/llvm-cov.cpp
@@ -47,6 +47,10 @@ static cl::opt<bool> FuncSummary("f", cl::Grouping, cl::init(false),
                                  cl::desc("Show coverage for each function"));
 static cl::alias FuncSummaryA("function-summaries", cl::aliasopt(FuncSummary));
 
+static cl::opt<bool> NoOutput("n", cl::Grouping, cl::init(false),
+                              cl::desc("Do not output any .gcov files"));
+static cl::alias NoOutputA("no-output", cl::aliasopt(NoOutput));
+
 static cl::opt<std::string>
 ObjectDir("o", cl::value_desc("DIR|FILE"), cl::init(""),
           cl::desc("Find objects in DIR or based on FILE's path"));
@@ -130,7 +134,7 @@ int main(int argc, char **argv) {
     GF.dump();
 
   GCOVOptions Options(AllBlocks, BranchProb, BranchCount, FuncSummary,
-                      PreservePaths, UncondBranch, LongNames);
+                      PreservePaths, UncondBranch, LongNames, NoOutput);
   FileInfo FI(Options);
   GF.collectLineCounts(FI);
   FI.print(SourceFile, InputGCNO, InputGCDA);