[llvm-dwarfdump] Adjust Windows path to be acceptable by JSON

[djtodoro]

Summary

Backslash is a special character according to JSON specification, so we should avoid that when printing a file path with the --statistics option.

[vsk]

tools/llvm-dwarfdump/Statistics.cpp

549

I think '\' needs to be converted to '\\'. Consider using llvm's json::Value(Filename), which should quote things correctly? I believe that can be passed to ostream directly, so you could templat-ize printDatum (getting rid of one of its duplicate definitions) and just pass the Filename json::Value in.

[djtodoro]

tools/llvm-dwarfdump/Statistics.cpp

549

Hmm... I didn't find any spec that says what is the desirable char in that case, but you are right. We can just pass this as a json::Value and it should know how to print that (it actually converts it into '\\'). Thanks! :)

[djtodoro]

-Use JSON::Value to get the right json when printing the stats

[vsk]

lgtm, I believe the original llvm-locstats can now land unmodified, which should provide test coverage.

[djtodoro]

@vsk Thanks!

tools/llvm-dwarfdump/Statistics.cpp

 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/DebugInfo/DIContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFDebugLoc.h"
 #include "llvm/Object/ObjectFile.h"
+#include "llvm/Support/JSON.h"
 
 #define DEBUG_TYPE "dwarfdump"
 using namespace llvm;
 using namespace object;
 
 /// This represents the number of categories of debug location coverage being
 /// calculated. The first category is the number of variables with 0% location
 /// coverage, but the last category is the number of variables with 100%
struct GlobalStats {
   /// Total number of call site entries (DW_AT_call_file & DW_AT_call_line).
   unsigned CallSiteEntries = 0;
   /// Total number of call site DIEs (DW_TAG_call_site).
   unsigned CallSiteDIEs = 0;
   /// Total number of call site parameter DIEs (DW_TAG_call_site_parameter).
   unsigned CallSiteParamDIEs = 0;
   /// Total byte size of concrete functions. This byte size includes
   /// inline functions contained in the concrete functions.
-  uint64_t FunctionSize = 0;
+  unsigned FunctionSize = 0;
   /// Total byte size of inlined functions. This is the total number of bytes
   /// for the top inline functions within concrete functions. This can help
   /// tune the inline settings when compiling to match user expectations.
-  uint64_t InlineFunctionSize = 0;
+  unsigned InlineFunctionSize = 0;
 };
 
 /// Holds accumulated debug location statistics about local variables and
 /// formal parameters.
 struct LocationStats {
   /// Map the scope coverage decile to the number of variables in the decile.
   /// The first element of the array (at the index zero) represents the number
   /// of variables with the no debug location at all, but the last element
collectStatsRecursive(Child, UnitLowPC, FnPrefix, ChildVarPrefix, ScopeLowPC,
                           LocStats);
     Child = Child.getSibling();
   }
 }
 
 /// Print machine-readable output.
 /// The machine-readable format is single-line JSON output.
 /// \{
-static void printDatum(raw_ostream &OS, const char *Key, StringRef Value) {
-  OS << ",\"" << Key << "\":\"" << Value << '"';
-  LLVM_DEBUG(llvm::dbgs() << Key << ": " << Value << '\n');
-}
-static void printDatum(raw_ostream &OS, const char *Key, uint64_t Value) {
+static void printDatum(raw_ostream &OS, const char *Key, json::Value Value) {
   OS << ",\"" << Key << "\":" << Value;
   LLVM_DEBUG(llvm::dbgs() << Key << ": " << Value << '\n');
 }
 static void printLocationStats(raw_ostream &OS,
                                const char *Key,
                                std::vector<unsigned> &LocationStats) {
   OS << ",\"" << Key << " with 0% of its scope covered\":"
      << LocationStats[0];
for (auto &Entry : Statistics) {
     VarTotal += Stats.NumVars;
     VarWithType += Stats.NumVarTypes;
     VarWithLoc += Stats.NumVarLocations;
     VarWithSrcLoc += Stats.NumVarSourceLocations;
   }
 
   // Print summary.
   OS.SetBufferSize(1024);
   OS << "{\"version\":" << Version;
   LLVM_DEBUG(llvm::dbgs() << "Variable location quality metrics\n";
              llvm::dbgs() << "---------------------------------\n");
   printDatum(OS, "file", Filename.str());
   printDatum(OS, "format", FormatName);
   printDatum(OS, "source functions", NumFunctions);
   printDatum(OS, "source functions with location", NumFuncsWithSrcLoc);
   printDatum(OS, "inlined functions", NumInlinedFunctions);
   printDatum(OS, "inlined funcs with abstract origins", NumAbstractOrigins);