[llvm-dwp] Refuse DWARFv5 input DWP files.

The library can parse DWARFv5 unit index sections of DWP files, but
llvm-dwp is not ready to process them. Refuse such input files for now.

Differential Revision: https://reviews.llvm.org/D77143

llvm/include/llvm/DebugInfo/DWARF/DWARFUnitIndex.h

@@ -139,6 +139,8 @@ public:
   bool parse(DataExtractor IndexData);
   void dump(raw_ostream &OS) const;
 
+  uint32_t getVersion() const { return Header.Version; }
+
   const Entry *getFromOffset(uint32_t Offset) const;
   const Entry *getFromHash(uint64_t Offset) const;
 

llvm/test/tools/llvm-dwp/X86/unsupported_cu_index_version.s

@@ -0,0 +1,33 @@
+# RUN: llvm-mc -triple x86_64-unknown-linux %s -filetype=obj -o %t.dwp
+# RUN: not llvm-dwp %t.dwp -o %t 2>&1 | FileCheck %s
+
+# CHECK: error: unsupported cu_index version: 5 (only version 2 is supported)
+
+## To reach the test point, no real data is needed in .debug_info.dwo,
+## but the section should not be empty.
+    .section .debug_info.dwo, "e", @progbits
+    .space 1
+
+    .section .debug_cu_index, "", @progbits
+## Header:
+    .short 5                        # Version
+    .space 2                        # Padding
+    .long 2                         # Section count
+    .long 1                         # Unit count
+    .long 2                         # Slot count
+## Hash Table of Signatures:
+    .quad 0x1100001122222222
+    .quad 0
+## Parallel Table of Indexes:
+    .long 1
+    .long 0
+## Table of Section Offsets:
+## Row 0:
+    .long 1                         # DW_SECT_INFO
+    .long 3                         # DW_SECT_ABBREV
+## Row 1:
+    .long 0
+    .long 0
+## Table of Section Sizes:
+    .long 1
+    .long 1

llvm/test/tools/llvm-dwp/X86/unsupported_tu_index_version.s

@@ -0,0 +1,81 @@
+# RUN: llvm-mc -triple x86_64-unknown-linux %s -filetype=obj -o %t.dwp
+# RUN: not llvm-dwp %t.dwp -o %t 2>&1 | FileCheck %s
+
+## Note: To reach the test point, we need a DWP file with a CU, a CU index
+## of version 2 and a TU index of version 5. A valid TU is not required, but
+## the .debug_types.dwo section should not be empty.
+
+# CHECK: error: unsupported tu_index version: 5 (only version 2 is supported)
+
+.section .debug_abbrev.dwo, "e", @progbits
+.LAbbrevBegin:
+    .uleb128 1                      # Abbreviation Code
+    .uleb128 17                     # DW_TAG_compile_unit
+    .byte 1                         # DW_CHILDREN_no
+    .uleb128 0x2131                 # DW_AT_GNU_dwo_id
+    .uleb128 7                      # DW_FORM_data8
+    .byte 0                         # EOM(1)
+    .byte 0                         # EOM(2)
+    .byte 0                         # EOM(3)
+.LAbbrevEnd:
+
+    .section .debug_info.dwo, "e", @progbits
+.LCUBegin:
+    .long .LCUEnd-.LCUVersion       # Length of Unit
+.LCUVersion:
+    .short 4                        # Version
+    .long 0                         # Abbrev offset
+    .byte 8                         # Address size
+    .uleb128 1                      # Abbrev [1] DW_TAG_compile_unit
+    .quad 0x1100001122222222        # DW_AT_GNU_dwo_id
+.LCUEnd:
+
+    .section .debug_types.dwo, "e", @progbits
+    .space 1
+
+    .section .debug_cu_index, "", @progbits
+## Header:
+    .long 2                         # Version
+    .long 2                         # Section count
+    .long 1                         # Unit count
+    .long 2                         # Slot count
+## Hash Table of Signatures:
+    .quad 0x1100001122222222
+    .quad 0
+## Parallel Table of Indexes:
+    .long 1
+    .long 0
+## Table of Section Offsets:
+## Row 0:
+    .long 1                         # DW_SECT_INFO
+    .long 3                         # DW_SECT_ABBREV
+## Row 1:
+    .long 0                         # Offset in .debug_info.dwo
+    .long 0                         # Offset in .debug_abbrev.dwo
+## Table of Section Sizes:
+    .long .LCUEnd-.LCUBegin         # Size in .debug_info.dwo
+    .long .LAbbrevEnd-.LAbbrevBegin # Size in .debug_abbrev.dwo
+
+    .section .debug_tu_index, "", @progbits
+## Header:
+    .short 5                        # Version
+    .space 2                        # Padding
+    .long 2                         # Section count
+    .long 1                         # Unit count
+    .long 2                         # Slot count
+## Hash Table of Signatures:
+    .quad 0x1100003333333333
+    .quad 0
+## Parallel Table of Indexes:
+    .long 1
+    .long 0
+## Table of Section Offsets:
+## Row 0:
+    .long 1                         # DW_SECT_INFO
+    .long 3                         # DW_SECT_ABBREV
+## Row 1:
+    .long 0
+    .long 0
+## Table of Section Sizes:
+    .long 1
+    .long 1

llvm/tools/llvm-dwp/llvm-dwp.cpp

@@ -618,6 +618,10 @@ static Error write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
     DataExtractor CUIndexData(CurCUIndexSection, Obj.isLittleEndian(), 0);
     if (!CUIndex.parse(CUIndexData))
       return make_error<DWPError>("failed to parse cu_index");
+    if (CUIndex.getVersion() != 2)
+      return make_error<DWPError>(
+          "unsupported cu_index version: " + utostr(CUIndex.getVersion()) +
+          " (only version 2 is supported)");
 
     for (const DWARFUnitIndex::Entry &E : CUIndex.getRows()) {
       auto *I = E.getContributions();
@@ -655,6 +659,11 @@ static Error write(MCStreamer &Out, ArrayRef<std::string> Inputs) {
       DataExtractor TUIndexData(CurTUIndexSection, Obj.isLittleEndian(), 0);
       if (!TUIndex.parse(TUIndexData))
         return make_error<DWPError>("failed to parse tu_index");
+      if (TUIndex.getVersion() != 2)
+        return make_error<DWPError>(
+            "unsupported tu_index version: " + utostr(TUIndex.getVersion()) +
+            " (only version 2 is supported)");
+
       addAllTypesFromDWP(
           Out, TypeIndexEntries, TUIndex, TypesSection, CurTypesSection.front(),
           CurEntry,