llvm-dwarfdump: Add support for -debug-info=<offset>.

This is the first of many commits that enable selectively dumping just
one record from the debug info.

This reapplies r313412 with some extra qualification to appease GCC and MSVC.

llvm-svn: 313419

1 files changed, 53 insertions, 45 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index c9832f43c24..3914b5a441a 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -216,7 +216,11 @@ static void dumpStringOffsetsSection(raw_ostream &OS, StringRef SectionName,
   }
 }
 
-void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
+void DWARFContext::dump(
+    raw_ostream &OS, DIDumpOptions DumpOpts,
+    std::array<Optional<uint64_t>, DIDT_ID_Count> DumpOffsets) {
+
+  Optional<uint64_t> DumpOffset;
   uint64_t DumpType = DumpOpts.DumpType;
   bool DumpEH = DumpOpts.DumpEH;
 
@@ -230,37 +234,41 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
 
   // Print a header for each explicitly-requested section.
   // Otherwise just print one for non-empty sections.
+  // Only print empty .dwo section headers when dumping a .dwo file.
   bool Explicit = DumpType != DIDT_All && !IsDWO;
-  auto shouldDump = [&](bool IsExplicit, const char *Name,
-                        unsigned DIDT_Section, StringRef Section) {
-    bool Should = (DumpType & DIDT_Section) && (IsExplicit || !Section.empty());
+  bool ExplicitDWO = Explicit && IsDWO;
+  auto shouldDump = [&](bool Explicit, const char *Name, unsigned ID,
+                        StringRef Section) {
+    DumpOffset = DumpOffsets[ID];
+    unsigned Mask = 1U << ID;
+    bool Should = (DumpType & Mask) && (Explicit || !Section.empty());
     if (Should)
-      OS << '\n' << Name << " contents:\n";
+      OS << "\n" << Name << " contents:\n";
     return Should;
   };
-  // Only print empty .dwo section headers when dumping a .dwo file.
-  bool ExplicitDWO = Explicit && IsDWO;
 
   // Dump individual sections.
-  if (shouldDump(Explicit, ".debug_abbrev", DIDT_DebugAbbrev,
-                 DObj->getAbbrevSection())) {
+  if (shouldDump(Explicit, ".debug_abbrev", DIDT_ID_DebugAbbrev,
+                 DObj->getAbbrevSection()))
     getDebugAbbrev()->dump(OS);
-  }
-  if (shouldDump(ExplicitDWO, ".debug_abbrev.dwo", DIDT_DebugAbbrev,
-                 DObj->getAbbrevDWOSection())) {
+  if (shouldDump(ExplicitDWO, ".debug_abbrev.dwo", DIDT_ID_DebugAbbrev,
+                 DObj->getAbbrevDWOSection()))
     getDebugAbbrevDWO()->dump(OS);
-  }
 
-  if (shouldDump(Explicit, ".debug_info", DIDT_DebugInfo,
-                 DObj->getInfoSection().Data)) {
-    for (const auto &CU : compile_units())
-      CU->dump(OS, DumpOpts);
-  }
-  if (shouldDump(ExplicitDWO, ".debug_info.dwo", DIDT_DebugInfo,
-                 DObj->getInfoDWOSection().Data)) {
-    for (const auto &DWOCU : dwo_compile_units())
-      DWOCU->dump(OS, DumpOpts);
-  }
+  auto dumpDebugInfo = [&](bool IsExplicit, const char *Name,
+                           DWARFSection Section, cu_iterator_range CUs) {
+    if (shouldDump(IsExplicit, Name, DIDT_ID_DebugInfo, Section.Data)) {
+      for (const auto &CU : CUs)
+        if (DumpOffset)
+        CU->getDIEForOffset(DumpOffset.getValue()).dump(OS, 0);
+        else
+          CU->dump(OS, DumpOpts);
+    }
+  };
+  dumpDebugInfo(Explicit, ".debug_info", DObj->getInfoSection(),
+                compile_units());
+  dumpDebugInfo(ExplicitDWO, ".debug_info.dwo", DObj->getInfoDWOSection(),
+                dwo_compile_units());
 
   if ((DumpType & DIDT_DebugTypes)) {
     if (Explicit || getNumTypeUnits()) {
@@ -277,16 +285,16 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
     }
   }
 
-  if (shouldDump(Explicit, ".debug_loc", DIDT_DebugLoc,
+  if (shouldDump(Explicit, ".debug_loc", DIDT_ID_DebugLoc,
                  DObj->getLocSection().Data)) {
     getDebugLoc()->dump(OS, getRegisterInfo());
   }
-  if (shouldDump(ExplicitDWO, ".debug_loc.dwo", DIDT_DebugLoc,
+  if (shouldDump(ExplicitDWO, ".debug_loc.dwo", DIDT_ID_DebugLoc,
                  DObj->getLocDWOSection().Data)) {
     getDebugLocDWO()->dump(OS, getRegisterInfo());
   }
 
-  if (shouldDump(Explicit, ".debug_frame", DIDT_DebugFrames,
+  if (shouldDump(Explicit, ".debug_frame", DIDT_ID_DebugFrames,
                  DObj->getDebugFrameSection())) {
     getDebugFrame()->dump(OS);
   }
@@ -302,7 +310,7 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
     }
   }
 
-  if (shouldDump(Explicit, ".debug_aranges", DIDT_DebugAranges,
+  if (shouldDump(Explicit, ".debug_aranges", DIDT_ID_DebugAranges,
                  DObj->getARangeSection())) {
     uint32_t offset = 0;
     DataExtractor arangesData(DObj->getARangeSection(), isLittleEndian(), 0);
@@ -312,7 +320,7 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
   }
 
   uint8_t savedAddressByteSize = 0;
-  if (shouldDump(Explicit, ".debug_line", DIDT_DebugLine,
+  if (shouldDump(Explicit, ".debug_line", DIDT_ID_DebugLine,
                  DObj->getLineSection().Data)) {
     for (const auto &CU : compile_units()) {
       savedAddressByteSize = CU->getAddressByteSize();
@@ -335,7 +343,7 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
     savedAddressByteSize = CU->getAddressByteSize();
     break;
   }
-  if (shouldDump(ExplicitDWO, ".debug_line.dwo", DIDT_DebugLine,
+  if (shouldDump(ExplicitDWO, ".debug_line.dwo", DIDT_ID_DebugLine,
                  DObj->getLineDWOSection().Data)) {
     unsigned stmtOffset = 0;
     DWARFDataExtractor lineData(*DObj, DObj->getLineDWOSection(),
@@ -347,17 +355,17 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
     }
   }
 
-  if (shouldDump(Explicit, ".debug_cu_index", DIDT_DebugCUIndex,
+  if (shouldDump(Explicit, ".debug_cu_index", DIDT_ID_DebugCUIndex,
                  DObj->getCUIndexSection())) {
     getCUIndex().dump(OS);
   }
 
-  if (shouldDump(Explicit, ".debug_tu_index", DIDT_DebugTUIndex,
+  if (shouldDump(Explicit, ".debug_tu_index", DIDT_ID_DebugTUIndex,
                  DObj->getTUIndexSection())) {
     getTUIndex().dump(OS);
   }
 
-  if (shouldDump(Explicit, ".debug_str", DIDT_DebugStr,
+  if (shouldDump(Explicit, ".debug_str", DIDT_ID_DebugStr,
                  DObj->getStringSection())) {
     DataExtractor strData(DObj->getStringSection(), isLittleEndian(), 0);
     uint32_t offset = 0;
@@ -367,7 +375,7 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
       strOffset = offset;
     }
   }
-  if (shouldDump(ExplicitDWO, ".debug_str.dwo", DIDT_DebugStr,
+  if (shouldDump(ExplicitDWO, ".debug_str.dwo", DIDT_ID_DebugStr,
                  DObj->getStringDWOSection())) {
     DataExtractor strDWOData(DObj->getStringDWOSection(), isLittleEndian(), 0);
     uint32_t offset = 0;
@@ -378,7 +386,7 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
     }
   }
 
-  if (shouldDump(Explicit, ".debug_ranges", DIDT_DebugRanges,
+  if (shouldDump(Explicit, ".debug_ranges", DIDT_ID_DebugRanges,
                  DObj->getRangeSection().Data)) {
     // In fact, different compile units may have different address byte
     // sizes, but for simplicity we just use the address byte size of the
@@ -393,60 +401,60 @@ void DWARFContext::dump(raw_ostream &OS, DIDumpOptions DumpOpts) {
       rangeList.dump(OS);
   }
 
-  if (shouldDump(Explicit, ".debug_pubnames", DIDT_DebugPubnames,
+  if (shouldDump(Explicit, ".debug_pubnames", DIDT_ID_DebugPubnames,
                  DObj->getPubNamesSection()))
     DWARFDebugPubTable(DObj->getPubNamesSection(), isLittleEndian(), false)
         .dump(OS);
 
-  if (shouldDump(Explicit, ".debug_pubtypes", DIDT_DebugPubtypes,
+  if (shouldDump(Explicit, ".debug_pubtypes", DIDT_ID_DebugPubtypes,
                  DObj->getPubTypesSection()))
     DWARFDebugPubTable(DObj->getPubTypesSection(), isLittleEndian(), false)
         .dump(OS);
 
-  if (shouldDump(Explicit, ".debug_gnu_pubnames", DIDT_DebugGnuPubnames,
+  if (shouldDump(Explicit, ".debug_gnu_pubnames", DIDT_ID_DebugGnuPubnames,
                  DObj->getGnuPubNamesSection()))
     DWARFDebugPubTable(DObj->getGnuPubNamesSection(), isLittleEndian(),
                        true /* GnuStyle */)
         .dump(OS);
 
-  if (shouldDump(Explicit, ".debug_gnu_pubtypes", DIDT_DebugGnuPubtypes,
+  if (shouldDump(Explicit, ".debug_gnu_pubtypes", DIDT_ID_DebugGnuPubtypes,
                  DObj->getGnuPubTypesSection()))
     DWARFDebugPubTable(DObj->getGnuPubTypesSection(), isLittleEndian(),
                        true /* GnuStyle */)
         .dump(OS);
 
-  if (shouldDump(Explicit, ".debug_str_offsets", DIDT_DebugStrOffsets,
+  if (shouldDump(Explicit, ".debug_str_offsets", DIDT_ID_DebugStrOffsets,
                  DObj->getStringOffsetSection().Data))
     dumpStringOffsetsSection(
         OS, "debug_str_offsets", *DObj, DObj->getStringOffsetSection(),
         DObj->getStringSection(), isLittleEndian(), getMaxVersion());
-  if (shouldDump(ExplicitDWO, ".debug_str_offsets.dwo", DIDT_DebugStrOffsets,
+  if (shouldDump(ExplicitDWO, ".debug_str_offsets.dwo", DIDT_ID_DebugStrOffsets,
                  DObj->getStringOffsetDWOSection().Data))
     dumpStringOffsetsSection(
         OS, "debug_str_offsets.dwo", *DObj, DObj->getStringOffsetDWOSection(),
         DObj->getStringDWOSection(), isLittleEndian(), getMaxVersion());
 
-  if (shouldDump(Explicit, ".gnu_index", DIDT_GdbIndex,
+  if (shouldDump(Explicit, ".gnu_index", DIDT_ID_GdbIndex,
                  DObj->getGdbIndexSection())) {
     getGdbIndex().dump(OS);
   }
 
-  if (shouldDump(Explicit, ".apple_names", DIDT_AppleNames,
+  if (shouldDump(Explicit, ".apple_names", DIDT_ID_AppleNames,
                  DObj->getAppleNamesSection().Data))
     dumpAccelSection(OS, *DObj, DObj->getAppleNamesSection(),
                      DObj->getStringSection(), isLittleEndian());
 
-  if (shouldDump(Explicit, ".apple_types", DIDT_AppleTypes,
+  if (shouldDump(Explicit, ".apple_types", DIDT_ID_AppleTypes,
                  DObj->getAppleTypesSection().Data))
     dumpAccelSection(OS, *DObj, DObj->getAppleTypesSection(),
                      DObj->getStringSection(), isLittleEndian());
 
-  if (shouldDump(Explicit, ".apple_namespaces", DIDT_AppleNamespaces,
+  if (shouldDump(Explicit, ".apple_namespaces", DIDT_ID_AppleNamespaces,
                  DObj->getAppleNamespacesSection().Data))
     dumpAccelSection(OS, *DObj, DObj->getAppleNamespacesSection(),
                      DObj->getStringSection(), isLittleEndian());
 
-  if (shouldDump(Explicit, ".apple_objc", DIDT_AppleObjC,
+  if (shouldDump(Explicit, ".apple_objc", DIDT_ID_AppleObjC,
                  DObj->getAppleObjCSection().Data))
     dumpAccelSection(OS, *DObj, DObj->getAppleObjCSection(),
                      DObj->getStringSection(), isLittleEndian());