[Coverage] Fix an issue where improper coverage mapping data could be loaded for an inline function.

If an inline function is observed but unused in a translation unit, dummy
coverage mapping data with zero hash is stored for this function.
If such a coverage mapping section came earlier than real one, the latter
was ignored. As a result, llvm-cov was unable to show coverage information
for those functions.

Differential Revision: http://reviews.llvm.org/D20286

llvm-svn: 270194

3 files changed, 30 insertions, 0 deletions

diff --git a/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.covmapping b/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.covmapping
new file mode 100644
index 00000000000..4722129fc18
--- /dev/null
+++ b/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.covmapping
diff --git a/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.cpp b/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.cpp
new file mode 100644
index 00000000000..a0892b1e156
--- /dev/null
+++ b/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.cpp
@@ -0,0 +1,5 @@
+#include "prefer_used_to_unused.h"
+
+int main() {
+  return sampleFunc(5) + simpleFunc(5);
+}
diff --git a/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.proftext b/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.proftext
new file mode 100644
index 00000000000..dd3e704a090
--- /dev/null
+++ b/llvm/test/tools/llvm-cov/Inputs/prefer_used_to_unused.proftext
@@ -0,0 +1,25 @@
+_Z10sampleFunci
+# Func Hash:
+10
+# Num Counters:
+2
+# Counter Values:
+1
+1
+
+main
+# Func Hash:
+0
+# Num Counters:
+1
+# Counter Values:
+1
+
+_Z10simpleFunci
+# Func Hash:
+0
+# Num Counters:
+1
+# Counter Values:
+1
+