[dwarf] Unify unknown dwarf enum formatting code

Summary:
We have had at least three pieces of code (in DWARFAbbreviationDeclaration,
DWARFAcceleratorTable and DWARFDie) that have hand-rolled support for
dumping unknown dwarf enum values. While not terrible, they are a bit
distracting and enable small differences to creep in (Unknown_ffff vs.
Unknown_0xffff). I ended up needing to add a fourth place
(DWARFVerifier), so it seems it would be a good time to centralize.

This patch creates an alternative to the XXXString dumping functions in
the BinaryFormat library, which formats an unknown value as
DW_TYPE_unknown_1234, instead of just an empty string. It is based on
the formatv function, as that allows us to avoid materializing the
string for unknown values (and because this way I don't have to invent a
name for the new functions :P).

In this patch I add formatters for dwarf attributes, forms, tags, and
index attributes as these are the ones in use currently, but adding
other enums is straight-forward.

Reviewers: dblaikie, JDevlieghere, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44570

llvm-svn: 328090

1 files changed, 6 insertions, 20 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
index 82f373e9c5c..7ae38e6e053 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDie.cpp
@@ -21,6 +21,7 @@
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Support/DataExtractor.h"
 #include "llvm/Support/Format.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/WithColor.h"
 #include "llvm/Support/raw_ostream.h"
@@ -188,20 +189,10 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die,
   const char BaseIndent[] = "            ";
   OS << BaseIndent;
   OS.indent(Indent + 2);
-  auto attrString = AttributeString(Attr);
-  if (!attrString.empty())
-    WithColor(OS, HighlightColor::Attribute) << attrString;
-  else
-    WithColor(OS, HighlightColor::Attribute).get()
-        << format("DW_AT_Unknown_%x", Attr);
+  WithColor(OS, HighlightColor::Attribute) << formatv("{0}", Attr);
 
-  if (DumpOpts.Verbose || DumpOpts.ShowForm) {
-    auto formString = FormEncodingString(Form);
-    if (!formString.empty())
-      OS << " [" << formString << ']';
-    else
-      OS << format(" [DW_FORM_Unknown_%x]", Form);
-  }
+  if (DumpOpts.Verbose || DumpOpts.ShowForm)
+    OS << formatv(" [{0}]", Form);
 
   DWARFUnit *U = Die.getDwarfUnit();
   DWARFFormValue formValue(Form);
@@ -465,13 +456,8 @@ void DWARFDie::dump(raw_ostream &OS, unsigned Indent,
     if (abbrCode) {
       auto AbbrevDecl = getAbbreviationDeclarationPtr();
       if (AbbrevDecl) {
-        auto tagString = TagString(getTag());
-        if (!tagString.empty())
-          WithColor(OS, HighlightColor::Tag).get().indent(Indent) << tagString;
-        else
-          WithColor(OS, HighlightColor::Tag).get().indent(Indent)
-              << format("DW_TAG_Unknown_%x", getTag());
-
+        WithColor(OS, HighlightColor::Tag).get().indent(Indent)
+            << formatv("{0}", getTag());
         if (DumpOpts.Verbose)
           OS << format(" [%u] %c", abbrCode,
                        AbbrevDecl->hasChildren() ? '*' : ' ');