[Coverage] Ensure that coverage mapping data has an expected alignment in 'covmapping' files.
Coverage mapping data is organized in a sequence of blocks, each of which is expected
to be aligned by 8 bytes. This feature is used when reading those blocks, see
VersionedCovMapFuncRecordReader::readFunctionRecords(). If a misaligned covearge
mapping data has more than one block, it causes llvm-cov to fail.
Differential Revision: http://reviews.llvm.org/D20285
llvm-svn: 269887
diff --git a/llvm/tools/llvm-cov/TestingSupport.cpp b/llvm/tools/llvm-cov/TestingSupport.cpp
index f6c91f8..a662a15 100644
--- a/llvm/tools/llvm-cov/TestingSupport.cpp
+++ b/llvm/tools/llvm-cov/TestingSupport.cpp
@@ -88,7 +88,11 @@
OS << "llvmcovmtestdata";
encodeULEB128(ProfileNamesData.size(), OS);
encodeULEB128(ProfileNamesAddress, OS);
- OS << ProfileNamesData << CoverageMappingData;
+ OS << ProfileNamesData;
+ // Coverage mapping data is expected to have an alignment of 8.
+ for (unsigned Pad = OffsetToAlignment(OS.tell(), 8); Pad; --Pad)
+ OS.write(uint8_t(0));
+ OS << CoverageMappingData;
return 0;
}