[LLDB] - Add support for DW_FORM_rnglistx and relative DW_RLE_* entries.

This adds support for DW_RLE_base_addressx, DW_RLE_startx_endx,
DW_RLE_startx_length, DW_FORM_rnglistx.

Differential revision: https://reviews.llvm.org/D53929

llvm-svn: 345958

5 files changed, 90 insertions, 21 deletions

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
index 91f8a45e0be..7531aeac709 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
@@ -157,6 +157,7 @@ bool DWARFDebugInfoEntry::FastExtract(
 
           // signed or unsigned LEB 128 values
           case DW_FORM_addrx:
+          case DW_FORM_rnglistx:
           case DW_FORM_sdata:
           case DW_FORM_udata:
           case DW_FORM_ref_udata:
@@ -387,6 +388,13 @@ void DWARFDebugInfoEntry::DumpAncestry(SymbolFileDWARF *dwarf2Data,
   Dump(dwarf2Data, cu, s, recurse_depth);
 }
 
+static dw_offset_t GetRangesOffset(const DWARFDebugRangesBase *debug_ranges,
+                                   DWARFFormValue &form_value) {
+  if (form_value.Form() == DW_FORM_rnglistx)
+    return debug_ranges->GetOffset(form_value.Unsigned());
+  return form_value.Unsigned();
+}
+
 //----------------------------------------------------------------------
 // GetDIENamesAndRanges
 //
@@ -464,7 +472,7 @@ bool DWARFDebugInfoEntry::GetDIENamesAndRanges(
         case DW_AT_ranges: {
           const DWARFDebugRangesBase *debug_ranges = dwarf2Data->DebugRanges();
           if (debug_ranges)
-            debug_ranges->FindRanges(cu, form_value.Unsigned(), ranges);
+            debug_ranges->FindRanges(cu, GetRangesOffset(debug_ranges, form_value), ranges);
           else
             cu->GetSymbolFileDWARF()->GetObjectFile()->GetModule()->ReportError(
                 "{0x%8.8x}: DIE has DW_AT_ranges(0x%" PRIx64
@@ -748,11 +756,13 @@ void DWARFDebugInfoEntry::DumpAttribute(
   } break;
 
   case DW_AT_ranges: {
-    lldb::offset_t ranges_offset = form_value.Unsigned();
+    if (!dwarf2Data)
+      break;
+    lldb::offset_t ranges_offset =
+        GetRangesOffset(dwarf2Data->DebugRanges(), form_value);
     dw_addr_t base_addr = cu ? cu->GetBaseAddress() : 0;
-    if (dwarf2Data)
-      DWARFDebugRanges::Dump(s, dwarf2Data->get_debug_ranges_data(),
-                             &ranges_offset, base_addr);
+    DWARFDebugRanges::Dump(s, dwarf2Data->get_debug_ranges_data(),
+                           &ranges_offset, base_addr);
   } break;
 
   default:
@@ -1062,12 +1072,11 @@ size_t DWARFDebugInfoEntry::GetAttributeAddressRanges(
     bool check_specification_or_abstract_origin) const {
   ranges.Clear();
 
-  dw_offset_t debug_ranges_offset = GetAttributeValueAsUnsigned(
-      dwarf2Data, cu, DW_AT_ranges, DW_INVALID_OFFSET,
-      check_specification_or_abstract_origin);
-  if (debug_ranges_offset != DW_INVALID_OFFSET) {
+  DWARFFormValue form_value;
+  if (GetAttributeValue(dwarf2Data, cu, DW_AT_ranges, form_value)) {
     if (DWARFDebugRangesBase *debug_ranges = dwarf2Data->DebugRanges())
-      debug_ranges->FindRanges(cu, debug_ranges_offset, ranges);
+      debug_ranges->FindRanges(cu, GetRangesOffset(debug_ranges, form_value),
+                               ranges);
   } else if (check_hi_lo_pc) {
     dw_addr_t lo_pc = LLDB_INVALID_ADDRESS;
     dw_addr_t hi_pc = LLDB_INVALID_ADDRESS;
@@ -1718,12 +1727,12 @@ bool DWARFDebugInfoEntry::LookupAddress(const dw_addr_t address,
                            ((function_die != NULL) || (block_die != NULL));
         }
       } else {
-        dw_offset_t debug_ranges_offset = GetAttributeValueAsUnsigned(
-            dwarf2Data, cu, DW_AT_ranges, DW_INVALID_OFFSET);
-        if (debug_ranges_offset != DW_INVALID_OFFSET) {
+        DWARFFormValue form_value;
+        if (GetAttributeValue(dwarf2Data, cu, DW_AT_ranges, form_value)) {
           DWARFRangeList ranges;
           DWARFDebugRangesBase *debug_ranges = dwarf2Data->DebugRanges();
-          debug_ranges->FindRanges(cu, debug_ranges_offset, ranges);
+          debug_ranges->FindRanges(
+              cu, GetRangesOffset(debug_ranges, form_value), ranges);
 
           if (ranges.FindEntryThatContains(address)) {
             found_address = true;
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.cpp
index 36771e55003..a0436dd7ffa 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.cpp
@@ -128,6 +128,11 @@ bool DWARFDebugRanges::FindRanges(const DWARFUnit *cu,
   return false;
 }
 
+uint64_t DWARFDebugRanges::GetOffset(size_t Index) const {
+  lldbassert(false && "DW_FORM_rnglistx is not present before DWARF5");
+  return 0;
+}
+
 bool DWARFDebugRngLists::ExtractRangeList(
     const DWARFDataExtractor &data, uint8_t addrSize,
     lldb::offset_t *offset_ptr, std::vector<RngListEntry> &rangeList) {
@@ -166,9 +171,27 @@ bool DWARFDebugRngLists::ExtractRangeList(
       break;
     }
 
+    case DW_RLE_base_addressx: {
+      dw_addr_t base = data.GetULEB128(offset_ptr);
+      rangeList.push_back({DW_RLE_base_addressx, base, 0});
+      break;
+    }
+
+    case DW_RLE_startx_endx: {
+      dw_addr_t start = data.GetULEB128(offset_ptr);
+      dw_addr_t end = data.GetULEB128(offset_ptr);
+      rangeList.push_back({DW_RLE_startx_endx, start, end});
+      break;
+    }
+
+    case DW_RLE_startx_length: {
+      dw_addr_t start = data.GetULEB128(offset_ptr);
+      dw_addr_t length = data.GetULEB128(offset_ptr);
+      rangeList.push_back({DW_RLE_startx_length, start, length});
+      break;
+    }
+
     default:
-      // Next encodings are not yet supported:
-      // DW_RLE_base_addressx, DW_RLE_startx_endx, DW_RLE_startx_length.
       lldbassert(0 && "unknown range list entry encoding");
       error = true;
     }
@@ -177,6 +200,15 @@ bool DWARFDebugRngLists::ExtractRangeList(
   return false;
 }
 
+static uint64_t ReadAddressFromDebugAddrSection(const DWARFUnit *cu,
+                                                uint32_t index) {
+  uint32_t index_size = cu->GetAddressByteSize();
+  dw_offset_t addr_base = cu->GetAddrBase();
+  lldb::offset_t offset = addr_base + index * index_size;
+  return cu->GetSymbolFileDWARF()->get_debug_addr_data().GetMaxU64(&offset,
+                                                                   index_size);
+}
+
 bool DWARFDebugRngLists::FindRanges(const DWARFUnit *cu,
                                     dw_offset_t debug_ranges_offset,
                                     DWARFRangeList &range_list) const {
@@ -200,6 +232,21 @@ bool DWARFDebugRngLists::FindRanges(const DWARFUnit *cu,
         range_list.Append(
             DWARFRangeList::Entry(BaseAddr + E.value0, E.value1 - E.value0));
         break;
+      case DW_RLE_base_addressx: {
+        BaseAddr = ReadAddressFromDebugAddrSection(cu, E.value0);
+        break;
+      }
+      case DW_RLE_startx_endx: {
+        dw_addr_t start = ReadAddressFromDebugAddrSection(cu, E.value0);
+        dw_addr_t end = ReadAddressFromDebugAddrSection(cu, E.value1);
+        range_list.Append(DWARFRangeList::Entry(start, end - start));
+        break;
+      }
+      case DW_RLE_startx_length: {
+        dw_addr_t start = ReadAddressFromDebugAddrSection(cu, E.value0);
+        range_list.Append(DWARFRangeList::Entry(start, E.value1));
+        break;
+      }
       default:
         llvm_unreachable("unexpected encoding");
       }
@@ -214,7 +261,8 @@ void DWARFDebugRngLists::Extract(SymbolFileDWARF *dwarf2Data) {
   lldb::offset_t offset = 0;
 
   uint64_t length = data.GetU32(&offset);
-  if (length == 0xffffffff)
+  bool isDwarf64 = (length == 0xffffffff);
+  if (isDwarf64)
     length = data.GetU64(&offset);
   lldb::offset_t end = offset + length;
 
@@ -232,7 +280,7 @@ void DWARFDebugRngLists::Extract(SymbolFileDWARF *dwarf2Data) {
 
   uint32_t offsetsAmount = data.GetU32(&offset);
   for (uint32_t i = 0; i < offsetsAmount; ++i)
-    Offsets.push_back(data.GetPointer(&offset));
+    Offsets.push_back(data.GetMaxU64(&offset, isDwarf64 ? 8 : 4));
 
   lldb::offset_t listOffset = offset;
   std::vector<RngListEntry> rangeList;
@@ -241,3 +289,7 @@ void DWARFDebugRngLists::Extract(SymbolFileDWARF *dwarf2Data) {
     listOffset = offset;
   }
 }
+
+uint64_t DWARFDebugRngLists::GetOffset(size_t Index) const {
+  return Offsets[Index];
+}
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.h b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.h
index b346d9291a4..5790f448ba8 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugRanges.h
@@ -22,15 +22,17 @@ public:
   virtual void Extract(SymbolFileDWARF *dwarf2Data) = 0;
   virtual bool FindRanges(const DWARFUnit *cu, dw_offset_t debug_ranges_offset,
                           DWARFRangeList &range_list) const = 0;
+  virtual uint64_t GetOffset(size_t Index) const = 0;
 };
 
 class DWARFDebugRanges final : public DWARFDebugRangesBase {
 public:
   DWARFDebugRanges();
 
-  virtual void Extract(SymbolFileDWARF *dwarf2Data) override;
-  virtual bool FindRanges(const DWARFUnit *cu, dw_offset_t debug_ranges_offset,
-                          DWARFRangeList &range_list) const override;
+  void Extract(SymbolFileDWARF *dwarf2Data) override;
+  bool FindRanges(const DWARFUnit *cu, dw_offset_t debug_ranges_offset,
+                  DWARFRangeList &range_list) const override;
+  uint64_t GetOffset(size_t Index) const override;
 
   static void Dump(lldb_private::Stream &s,
                    const lldb_private::DWARFDataExtractor &debug_ranges_data,
@@ -58,6 +60,7 @@ public:
   void Extract(SymbolFileDWARF *dwarf2Data) override;
   bool FindRanges(const DWARFUnit *cu, dw_offset_t debug_ranges_offset,
                   DWARFRangeList &range_list) const override;
+  uint64_t GetOffset(size_t Index) const override;
 
 protected:
   bool ExtractRangeList(const lldb_private::DWARFDataExtractor &data,
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFFormValue.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFFormValue.cpp
index a70572858d9..c888d0bc3e6 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFFormValue.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFFormValue.cpp
@@ -248,6 +248,7 @@ bool DWARFFormValue::ExtractValue(const DWARFDataExtractor &data,
       m_value.value.uval = data.GetU64(offset_ptr);
       break;
     case DW_FORM_addrx:
+    case DW_FORM_rnglistx:
     case DW_FORM_strx:
     case DW_FORM_udata:
     case DW_FORM_ref_udata:
@@ -393,6 +394,7 @@ bool DWARFFormValue::SkipValue(dw_form_t form,
 
     // signed or unsigned LEB 128 values
     case DW_FORM_addrx:
+    case DW_FORM_rnglistx:
     case DW_FORM_sdata:
     case DW_FORM_udata:
     case DW_FORM_ref_udata:
@@ -777,6 +779,7 @@ bool DWARFFormValue::FormIsSupported(dw_form_t form) {
   switch (form) {
     case DW_FORM_addr:
     case DW_FORM_addrx:
+    case DW_FORM_rnglistx:
     case DW_FORM_block2:
     case DW_FORM_block4:
     case DW_FORM_data2:
diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
index 271f44f24b9..7236a0599e6 100644
--- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp
@@ -309,6 +309,8 @@ void DWARFUnit::ExtractDIEsEndCheck(lldb::offset_t offset) const {
 void DWARFUnit::AddUnitDIE(const DWARFDebugInfoEntry &cu_die) {
   SetAddrBase(
       cu_die.GetAttributeValueAsUnsigned(m_dwarf, this, DW_AT_addr_base, 0));
+  SetRangesBase(cu_die.GetAttributeValueAsUnsigned(m_dwarf, this,
+                                                   DW_AT_rnglists_base, 0));
 
   uint64_t base_addr = cu_die.GetAttributeValueAsAddress(
       m_dwarf, this, DW_AT_low_pc, LLDB_INVALID_ADDRESS);