Revert "[Coverage] Revise format to reduce binary size"

This reverts commit 99317124e1c772e9a9de41a0cd56e1db049b4ea4. This is
still busted on Windows:

http://lab.llvm.org:8011/builders/lld-x86_64-win7/builds/40873

The llvm-cov tests report 'error: Could not load coverage information'.

1 files changed, 5 insertions, 29 deletions

diff --git a/llvm/lib/ProfileData/Coverage/CoverageMappingWriter.cpp b/llvm/lib/ProfileData/Coverage/CoverageMappingWriter.cpp
index 8d3c429..d75854a 100644
--- a/llvm/lib/ProfileData/Coverage/CoverageMappingWriter.cpp
+++ b/llvm/lib/ProfileData/Coverage/CoverageMappingWriter.cpp
@@ -11,11 +11,9 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/ProfileData/InstrProf.h"
 #include "llvm/ProfileData/Coverage/CoverageMappingWriter.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallVector.h"
-#include "llvm/Support/Compression.h"
 #include "llvm/Support/LEB128.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
@@ -36,34 +34,12 @@ CoverageFilenamesSectionWriter::CoverageFilenamesSectionWriter(
 #endif
 }
 
-void CoverageFilenamesSectionWriter::write(raw_ostream &OS, bool Compress) {
-  std::string FilenamesStr;
-  {
-    raw_string_ostream FilenamesOS{FilenamesStr};
-    for (const auto &Filename : Filenames) {
-      encodeULEB128(Filename.size(), FilenamesOS);
-      FilenamesOS << Filename;
-    }
-  }
-
-  SmallString<128> CompressedStr;
-  bool doCompression =
-      Compress && zlib::isAvailable() && DoInstrProfNameCompression;
-  if (doCompression) {
-    auto E =
-        zlib::compress(FilenamesStr, CompressedStr, zlib::BestSizeCompression);
-    if (E)
-      report_bad_alloc_error("Failed to zlib compress coverage data");
-  }
-
-  // ::= <num-filenames>
-  //     <uncompressed-len>
-  //     <compressed-len-or-zero>
-  //     (<compressed-filenames> | <uncompressed-filenames>)
+void CoverageFilenamesSectionWriter::write(raw_ostream &OS) {
   encodeULEB128(Filenames.size(), OS);
-  encodeULEB128(FilenamesStr.size(), OS);
-  encodeULEB128(doCompression ? CompressedStr.size() : 0U, OS);
-  OS << (doCompression ? StringRef(CompressedStr) : StringRef(FilenamesStr));
+  for (const auto &Filename : Filenames) {
+    encodeULEB128(Filename.size(), OS);
+    OS << Filename;
+  }
 }
 
 namespace {