[DWARF] Fix referencing Range List Tables from CUs for DWARF64.

As DW_AT_rnglists_base points after the header and headers have
different sizes for DWARF32 and DWARF64, we have to use the format
of the CU to adjust the offset correctly in order to extract
the referenced range list table.

The patch also changes the type of RangeSectionBase because in DWARF64
it is 8-bytes long.

Differential Revision: https://reviews.llvm.org/D67098

llvm-svn: 371016

1 files changed, 12 insertions, 9 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
index 51b5f59f835..a56402a707a 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -306,16 +306,18 @@ bool DWARFUnitHeader::extract(DWARFContext &Context,
 // Parse the rangelist table header, including the optional array of offsets
 // following it (DWARF v5 and later).
 static Expected<DWARFDebugRnglistTable>
-parseRngListTableHeader(DWARFDataExtractor &DA, uint64_t Offset) {
-  // TODO: Support DWARF64
+parseRngListTableHeader(DWARFDataExtractor &DA, uint64_t Offset,
+                        DwarfFormat Format) {
   // We are expected to be called with Offset 0 or pointing just past the table
-  // header, which is 12 bytes long for DWARF32.
+  // header. Correct Offset in the latter case so that it points to the start
+  // of the header.
   if (Offset > 0) {
-    if (Offset < 12U)
+    uint64_t HeaderSize = DWARFListTableHeader::getHeaderSize(Format);
+    if (Offset < HeaderSize)
       return createStringError(errc::invalid_argument, "Did not detect a valid"
-                               " range list table with base = 0x%" PRIx64,
+                               " range list table with base = 0x%" PRIx64 "\n",
                                Offset);
-    Offset -= 12U;
+    Offset -= HeaderSize;
   }
   llvm::DWARFDebugRnglistTable Table;
   if (Error E = Table.extractHeaderAndOffsets(DA, &Offset))
@@ -469,8 +471,8 @@ Error DWARFUnit::tryExtractDIEsIfNeeded(bool CUDieOnly) {
       // extracted lazily.
       DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
                                   isLittleEndian, 0);
-      auto TableOrError =
-              parseRngListTableHeader(RangesDA, RangeSectionBase);
+      auto TableOrError = parseRngListTableHeader(RangesDA, RangeSectionBase,
+                                                  Header.getFormat());
       if (!TableOrError)
         return createStringError(errc::invalid_argument,
                                  "parsing a range list table: " +
@@ -525,7 +527,8 @@ bool DWARFUnit::parseDWO() {
     DWO->setRangesSection(&Context.getDWARFObj().getRnglistsDWOSection(), 0);
     DWARFDataExtractor RangesDA(Context.getDWARFObj(), *RangeSection,
                                 isLittleEndian, 0);
-    if (auto TableOrError = parseRngListTableHeader(RangesDA, RangeSectionBase))
+    if (auto TableOrError = parseRngListTableHeader(RangesDA, RangeSectionBase,
+                                                    Header.getFormat()))
       DWO->RngListTable = TableOrError.get();
     else
       WithColor::error() << "parsing a range list table: "