[Lldb-commits] [lldb] fcaf5f6 - [LLDB] Fix the handling of unnamed bit-fields when parsing DWARF

Hans Wennborg via lldb-commits lldb-commits at lists.llvm.org
Tue Jan 28 05:25:28 PST 2020


Cherry-picked that in 54b022d344412fc9f1dfe37ee05de934a01e1ea4

Thanks!

On Tue, Jan 28, 2020 at 1:12 AM Raphael Isemann <risemann at apple.com> wrote:
>
> Quick follow up: apparently Pavel fixed some nondeterminism in the testing code that had made the test fail on some systems. Could you also cherry-pick 77cedb0cdb8623ff9eb22dbf3b9302ee4d9f8a20 ?
>
> Thanks again!
>
> > On 27. Jan 2020, at 15:10, Hans Wennborg <hans at chromium.org> wrote:
> >
> > Sure, b5cf892651812003e64c4a8f0dbf81f74a499016
> >
> > On Mon, Jan 27, 2020 at 12:18 AM Raphael Isemann <risemann at apple.com> wrote:
> >>
> >> This commit fixes a *very* frequent crash when debugging Clang with LLDB 10. Could we get that cherry-picked into the 10.x branch?
> >>
> >> I’ve been running the patch since more than a week and I haven’t found any issues with it and the bots are also happy.
> >>
> >> Thanks!
> >> - Raphael
> >>
> >>> On 23. Jan 2020, at 23:46, via lldb-commits <lldb-commits at lists.llvm.org> wrote:
> >>>
> >>>
> >>> Author: shafik
> >>> Date: 2020-01-23T14:46:24-08:00
> >>> New Revision: fcaf5f6c01a09f23b948afb8c91c4dd951d4525e
> >>>
> >>> URL: https://github.com/llvm/llvm-project/commit/fcaf5f6c01a09f23b948afb8c91c4dd951d4525e
> >>> DIFF: https://github.com/llvm/llvm-project/commit/fcaf5f6c01a09f23b948afb8c91c4dd951d4525e.diff
> >>>
> >>> LOG: [LLDB] Fix the handling of unnamed bit-fields when parsing DWARF
> >>>
> >>> We ran into an assert when debugging clang and performing an expression on a class derived from DeclContext. The assert was indicating we were getting the offsets wrong for RecordDeclBitfields. We were getting both the size and offset of unnamed bit-field members wrong. We could fix this case with a quick change but as I extended the test suite to include more combinations we kept finding more cases that were being handled incorrectly. A fix that handled all the new cases as well as the cases already covered required a refactor of the existing technique.
> >>>
> >>> Differential Revision: https://reviews.llvm.org/D72953
> >>>
> >>> Added:
> >>>   lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/Makefile
> >>>   lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/TestCppBitfields.py
> >>>   lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/main.cpp
> >>>
> >>> Modified:
> >>>   lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
> >>>   lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.h
> >>>
> >>> Removed:
> >>>
> >>>
> >>>
> >>> ################################################################################
> >>> diff  --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/Makefile b/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/Makefile
> >>> new file mode 100644
> >>> index 000000000000..99998b20bcb0
> >>> --- /dev/null
> >>> +++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/Makefile
> >>> @@ -0,0 +1,3 @@
> >>> +CXX_SOURCES := main.cpp
> >>> +
> >>> +include Makefile.rules
> >>>
> >>> diff  --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/TestCppBitfields.py b/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/TestCppBitfields.py
> >>> new file mode 100644
> >>> index 000000000000..696e5647f13f
> >>> --- /dev/null
> >>> +++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/TestCppBitfields.py
> >>> @@ -0,0 +1,105 @@
> >>> +"""Show bitfields and check that they display correctly."""
> >>> +
> >>> +import lldb
> >>> +from lldbsuite.test.decorators import *
> >>> +from lldbsuite.test.lldbtest import *
> >>> +from lldbsuite.test import lldbutil
> >>> +
> >>> +
> >>> +class CppBitfieldsTestCase(TestBase):
> >>> +
> >>> +    mydir = TestBase.compute_mydir(__file__)
> >>> +
> >>> +    def setUp(self):
> >>> +        # Call super's setUp().
> >>> +        TestBase.setUp(self)
> >>> +        # Find the line number to break inside main().
> >>> +        self.line = line_number('main.cpp', '// Set break point at this line.')
> >>> +
> >>> +    # BitFields exhibit crashes in record layout on Windows
> >>> +    # (http://llvm.org/pr21800)
> >>> +    @skipIfWindows
> >>> +    def test_and_run_command(self):
> >>> +        """Test 'frame variable ...' on a variable with bitfields."""
> >>> +        self.build()
> >>> +
> >>> +        lldbutil.run_to_source_breakpoint(self, '// Set break point at this line.',
> >>> +          lldb.SBFileSpec("main.cpp", False))
> >>> +
> >>> +        # The stop reason of the thread should be breakpoint.
> >>> +        self.expect("thread list", STOPPED_DUE_TO_BREAKPOINT,
> >>> +                    substrs=['stopped',
> >>> +                             'stop reason = breakpoint'])
> >>> +
> >>> +        # The breakpoint should have a hit count of 1.
> >>> +        self.expect("breakpoint list -f", BREAKPOINT_HIT_ONCE,
> >>> +                    substrs=[' resolved, hit count = 1'])
> >>> +
> >>> +        self.expect("expr (lba.a)", VARIABLES_DISPLAYED_CORRECTLY,
> >>> +                    substrs=['unsigned int', '2'])
> >>> +        self.expect("expr (lbb.b)", VARIABLES_DISPLAYED_CORRECTLY,
> >>> +                    substrs=['unsigned int', '3'])
> >>> +        self.expect("expr (lbc.c)", VARIABLES_DISPLAYED_CORRECTLY,
> >>> +                    substrs=['unsigned int', '4'])
> >>> +        self.expect("expr (lbd.a)", VARIABLES_DISPLAYED_CORRECTLY,
> >>> +                    substrs=['unsigned int', '5'])
> >>> +        self.expect("expr (clang_example.f.a)", VARIABLES_DISPLAYED_CORRECTLY,
> >>> +                    substrs=['uint64_t', '1'])
> >>> +
> >>> +        self.expect(
> >>> +            "frame variable --show-types lba",
> >>> +            VARIABLES_DISPLAYED_CORRECTLY,
> >>> +            substrs=[
> >>> +                '(int:32)  = ',
> >>> +                '(unsigned int:20) a = 2',
> >>> +                ])
> >>> +
> >>> +        self.expect(
> >>> +            "frame variable --show-types lbb",
> >>> +            VARIABLES_DISPLAYED_CORRECTLY,
> >>> +            substrs=[
> >>> +                '(unsigned int:1) a = 1',
> >>> +                '(int:31)  =',
> >>> +                '(unsigned int:20) b = 3',
> >>> +                ])
> >>> +
> >>> +        self.expect(
> >>> +            "frame variable --show-types lbc",
> >>> +            VARIABLES_DISPLAYED_CORRECTLY,
> >>> +            substrs=[
> >>> +                '(int:22)  =',
> >>> +                '(unsigned int:1) a = 1',
> >>> +                '(unsigned int:1) b = 0',
> >>> +                '(unsigned int:5) c = 4',
> >>> +                '(unsigned int:1) d = 1',
> >>> +                '(int:2)  =',
> >>> +                '(unsigned int:20) e = 20',
> >>> +                ])
> >>> +
> >>> +        self.expect(
> >>> +            "frame variable --show-types lbd",
> >>> +            VARIABLES_DISPLAYED_CORRECTLY,
> >>> +            substrs=[
> >>> +                '(char [3]) arr = "abc"',
> >>> +                '(int:32)  =',
> >>> +                '(unsigned int:20) a = 5',
> >>> +                ])
> >>> +
> >>> +        self.expect(
> >>> +            "frame variable --show-types clang_example",
> >>> +            VARIABLES_DISPLAYED_CORRECTLY,
> >>> +            substrs=[
> >>> +                   '(int:22)  =',
> >>> +                   '(uint64_t:1) a = 1',
> >>> +                   '(uint64_t:1) b = 0',
> >>> +                   '(uint64_t:1) c = 1',
> >>> +                   '(uint64_t:1) d = 0',
> >>> +                   '(uint64_t:1) e = 1',
> >>> +                   '(uint64_t:1) f = 0',
> >>> +                   '(uint64_t:1) g = 1',
> >>> +                   '(uint64_t:1) h = 0',
> >>> +                   '(uint64_t:1) i = 1',
> >>> +                   '(uint64_t:1) j = 0',
> >>> +                   '(uint64_t:1) k = 1',
> >>> +                ])
> >>> +
> >>>
> >>> diff  --git a/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/main.cpp b/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/main.cpp
> >>> new file mode 100644
> >>> index 000000000000..975c0f05683c
> >>> --- /dev/null
> >>> +++ b/lldb/packages/Python/lldbsuite/test/lang/cpp/bitfields/main.cpp
> >>> @@ -0,0 +1,81 @@
> >>> +#include <stdint.h>
> >>> +
> >>> +int main(int argc, char const *argv[]) {
> >>> +  struct LargeBitsA {
> >>> +    unsigned int : 30, a : 20;
> >>> +  } lba;
> >>> +
> >>> +  struct LargeBitsB {
> >>> +    unsigned int a : 1, : 11, : 12, b : 20;
> >>> +  } lbb;
> >>> +
> >>> +  struct LargeBitsC {
> >>> +    unsigned int : 13, : 9, a : 1, b : 1, c : 5, d : 1, e : 20;
> >>> +  } lbc;
> >>> +
> >>> +  struct LargeBitsD {
> >>> +    char arr[3];
> >>> +    unsigned int : 30, a : 20;
> >>> +  } lbd;
> >>> +
> >>> +  // This case came up when debugging clang and models RecordDeclBits
> >>> +  struct BitExampleFromClangDeclContext {
> >>> +    class fields {
> >>> +      uint64_t : 13;
> >>> +      uint64_t : 9;
> >>> +
> >>> +      uint64_t a: 1;
> >>> +      uint64_t b: 1;
> >>> +      uint64_t c: 1;
> >>> +      uint64_t d: 1;
> >>> +      uint64_t e: 1;
> >>> +      uint64_t f: 1;
> >>> +      uint64_t g: 1;
> >>> +      uint64_t h: 1;
> >>> +      uint64_t i: 1;
> >>> +      uint64_t j: 1;
> >>> +      uint64_t k: 1;
> >>> +
> >>> +      // In order to reproduce the crash for this case we need the
> >>> +      // members of fields to stay private :-(
> >>> +      friend struct BitExampleFromClangDeclContext;
> >>> +    };
> >>> +
> >>> +    union {
> >>> +      struct fields f;
> >>> +    };
> >>> +
> >>> +    BitExampleFromClangDeclContext() {
> >>> +  f.a = 1;
> >>> +  f.b = 0;
> >>> +  f.c = 1;
> >>> +  f.d = 0;
> >>> +  f.e = 1;
> >>> +  f.f = 0;
> >>> +  f.g = 1;
> >>> +  f.h = 0;
> >>> +  f.i = 1;
> >>> +  f.j = 0;
> >>> +  f.k = 1;
> >>> +    }
> >>> +  } clang_example;
> >>> +
> >>> +  lba.a = 2;
> >>> +
> >>> +  lbb.a = 1;
> >>> +  lbb.b = 3;
> >>> +
> >>> +  lbc.a = 1;
> >>> +  lbc.b = 0;
> >>> +  lbc.c = 4;
> >>> +  lbc.d = 1;
> >>> +  lbc.e = 20;
> >>> +
> >>> +  lbd.arr[0] = 'a';
> >>> +  lbd.arr[1] = 'b';
> >>> +  lbd.arr[2] = 'c';
> >>> +  lbd.a = 5;
> >>> +
> >>> +
> >>> +  return 0; // Set break point at this line.
> >>> +}
> >>>
> >>> diff  --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
> >>> index 1aa82ab67ce6..7a610e042b48 100644
> >>> --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
> >>> +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
> >>> @@ -85,35 +85,6 @@ static bool DeclKindIsCXXClass(clang::Decl::Kind decl_kind) {
> >>>  return false;
> >>> }
> >>>
> >>> -struct BitfieldInfo {
> >>> -  uint64_t bit_size;
> >>> -  uint64_t bit_offset;
> >>> -
> >>> -  BitfieldInfo()
> >>> -      : bit_size(LLDB_INVALID_ADDRESS), bit_offset(LLDB_INVALID_ADDRESS) {}
> >>> -
> >>> -  void Clear() {
> >>> -    bit_size = LLDB_INVALID_ADDRESS;
> >>> -    bit_offset = LLDB_INVALID_ADDRESS;
> >>> -  }
> >>> -
> >>> -  bool IsValid() const {
> >>> -    return (bit_size != LLDB_INVALID_ADDRESS) &&
> >>> -           (bit_offset != LLDB_INVALID_ADDRESS);
> >>> -  }
> >>> -
> >>> -  bool NextBitfieldOffsetIsValid(const uint64_t next_bit_offset) const {
> >>> -    if (IsValid()) {
> >>> -      // This bitfield info is valid, so any subsequent bitfields must not
> >>> -      // overlap and must be at a higher bit offset than any previous bitfield
> >>> -      // + size.
> >>> -      return (bit_size + bit_offset) <= next_bit_offset;
> >>> -    } else {
> >>> -      // If the this BitfieldInfo is not valid, then any offset isOK
> >>> -      return true;
> >>> -    }
> >>> -  }
> >>> -};
> >>>
> >>> ClangASTImporter &DWARFASTParserClang::GetClangASTImporter() {
> >>>  if (!m_clang_ast_importer_up) {
> >>> @@ -2419,7 +2390,7 @@ void DWARFASTParserClang::ParseSingleMember(
> >>>    lldb::AccessType &default_accessibility,
> >>>    DelayedPropertyList &delayed_properties,
> >>>    lldb_private::ClangASTImporter::LayoutInfo &layout_info,
> >>> -    BitfieldInfo &last_field_info) {
> >>> +    FieldInfo &last_field_info) {
> >>>  ModuleSP module_sp = parent_die.GetDWARF()->GetObjectFile()->GetModule();
> >>>  const dw_tag_t tag = die.Tag();
> >>>  // Get the parent byte size so we can verify any members will fit
> >>> @@ -2453,6 +2424,14 @@ void DWARFASTParserClang::ParseSingleMember(
> >>>      const dw_attr_t attr = attributes.AttributeAtIndex(i);
> >>>      DWARFFormValue form_value;
> >>>      if (attributes.ExtractFormValueAtIndex(i, form_value)) {
> >>> +        // DW_AT_data_member_location indicates the byte offset of the
> >>> +        // word from the base address of the structure.
> >>> +        //
> >>> +        // DW_AT_bit_offset indicates how many bits into the word
> >>> +        // (according to the host endianness) the low-order bit of the
> >>> +        // field starts.  AT_bit_offset can be negative.
> >>> +        //
> >>> +        // DW_AT_bit_size indicates the size of the field in bits.
> >>>        switch (attr) {
> >>>        case DW_AT_name:
> >>>          name = form_value.AsCString();
> >>> @@ -2603,36 +2582,24 @@ void DWARFASTParserClang::ParseSingleMember(
> >>>      Type *member_type = die.ResolveTypeUID(encoding_form.Reference());
> >>>
> >>>      clang::FieldDecl *field_decl = nullptr;
> >>> +      const uint64_t character_width = 8;
> >>> +      const uint64_t word_width = 32;
> >>>      if (tag == DW_TAG_member) {
> >>>        if (member_type) {
> >>> +          CompilerType member_clang_type = member_type->GetLayoutCompilerType();
> >>> +
> >>>          if (accessibility == eAccessNone)
> >>>            accessibility = default_accessibility;
> >>>          member_accessibilities.push_back(accessibility);
> >>>
> >>>          uint64_t field_bit_offset =
> >>>              (member_byte_offset == UINT32_MAX ? 0 : (member_byte_offset * 8));
> >>> -          if (bit_size > 0) {
> >>>
> >>> -            BitfieldInfo this_field_info;
> >>> +          if (bit_size > 0) {
> >>> +            FieldInfo this_field_info;
> >>>            this_field_info.bit_offset = field_bit_offset;
> >>>            this_field_info.bit_size = bit_size;
> >>>
> >>> -            /////////////////////////////////////////////////////////////
> >>> -            // How to locate a field given the DWARF debug information
> >>> -            //
> >>> -            // AT_byte_size indicates the size of the word in which the bit
> >>> -            // offset must be interpreted.
> >>> -            //
> >>> -            // AT_data_member_location indicates the byte offset of the
> >>> -            // word from the base address of the structure.
> >>> -            //
> >>> -            // AT_bit_offset indicates how many bits into the word
> >>> -            // (according to the host endianness) the low-order bit of the
> >>> -            // field starts.  AT_bit_offset can be negative.
> >>> -            //
> >>> -            // AT_bit_size indicates the size of the field in bits.
> >>> -            /////////////////////////////////////////////////////////////
> >>> -
> >>>            if (data_bit_offset != UINT64_MAX) {
> >>>              this_field_info.bit_offset = data_bit_offset;
> >>>            } else {
> >>> @@ -2649,8 +2616,9 @@ void DWARFASTParserClang::ParseSingleMember(
> >>>            }
> >>>
> >>>            if ((this_field_info.bit_offset >= parent_bit_size) ||
> >>> -                !last_field_info.NextBitfieldOffsetIsValid(
> >>> -                    this_field_info.bit_offset)) {
> >>> +                (last_field_info.IsBitfield() &&
> >>> +                 !last_field_info.NextBitfieldOffsetIsValid(
> >>> +                     this_field_info.bit_offset))) {
> >>>              ObjectFile *objfile = die.GetDWARF()->GetObjectFile();
> >>>              objfile->GetModule()->ReportWarning(
> >>>                  "0x%8.8" PRIx64 ": %s bitfield named \"%s\" has invalid "
> >>> @@ -2659,40 +2627,12 @@ void DWARFASTParserClang::ParseSingleMember(
> >>>                  "compiler and include the preprocessed output for %s\n",
> >>>                  die.GetID(), DW_TAG_value_to_name(tag), name,
> >>>                  this_field_info.bit_offset, GetUnitName(parent_die).c_str());
> >>> -              this_field_info.Clear();
> >>>              return;
> >>>            }
> >>>
> >>>            // Update the field bit offset we will report for layout
> >>>            field_bit_offset = this_field_info.bit_offset;
> >>>
> >>> -            // If the member to be emitted did not start on a character
> >>> -            // boundary and there is empty space between the last field and
> >>> -            // this one, then we need to emit an anonymous member filling
> >>> -            // up the space up to its start.  There are three cases here:
> >>> -            //
> >>> -            // 1 If the previous member ended on a character boundary, then
> >>> -            // we can emit an
> >>> -            //   anonymous member starting at the most recent character
> >>> -            //   boundary.
> >>> -            //
> >>> -            // 2 If the previous member did not end on a character boundary
> >>> -            // and the distance
> >>> -            //   from the end of the previous member to the current member
> >>> -            //   is less than a
> >>> -            //   word width, then we can emit an anonymous member starting
> >>> -            //   right after the
> >>> -            //   previous member and right before this member.
> >>> -            //
> >>> -            // 3 If the previous member did not end on a character boundary
> >>> -            // and the distance
> >>> -            //   from the end of the previous member to the current member
> >>> -            //   is greater than
> >>> -            //   or equal a word width, then we act as in Case 1.
> >>> -
> >>> -            const uint64_t character_width = 8;
> >>> -            const uint64_t word_width = 32;
> >>> -
> >>>            // Objective-C has invalid DW_AT_bit_offset values in older
> >>>            // versions of clang, so we have to be careful and only insert
> >>>            // unnamed bitfields if we have a new enough clang.
> >>> @@ -2704,53 +2644,57 @@ void DWARFASTParserClang::ParseSingleMember(
> >>>                  die.GetCU()->Supports_unnamed_objc_bitfields();
> >>>
> >>>            if (detect_unnamed_bitfields) {
> >>> -              BitfieldInfo anon_field_info;
> >>> -
> >>> -              if ((this_field_info.bit_offset % character_width) !=
> >>> -                  0) // not char aligned
> >>> -              {
> >>> -                uint64_t last_field_end = 0;
> >>> -
> >>> -                if (last_field_info.IsValid())
> >>> -                  last_field_end =
> >>> -                      last_field_info.bit_offset + last_field_info.bit_size;
> >>> -
> >>> -                if (this_field_info.bit_offset != last_field_end) {
> >>> -                  if (((last_field_end % character_width) == 0) || // case 1
> >>> -                      (this_field_info.bit_offset - last_field_end >=
> >>> -                       word_width)) // case 3
> >>> -                  {
> >>> -                    anon_field_info.bit_size =
> >>> -                        this_field_info.bit_offset % character_width;
> >>> -                    anon_field_info.bit_offset =
> >>> -                        this_field_info.bit_offset - anon_field_info.bit_size;
> >>> -                  } else // case 2
> >>> -                  {
> >>> -                    anon_field_info.bit_size =
> >>> -                        this_field_info.bit_offset - last_field_end;
> >>> -                    anon_field_info.bit_offset = last_field_end;
> >>> -                  }
> >>> -                }
> >>> +              clang::Optional<FieldInfo> unnamed_field_info;
> >>> +              uint64_t last_field_end = 0;
> >>> +
> >>> +              last_field_end =
> >>> +                  last_field_info.bit_offset + last_field_info.bit_size;
> >>> +
> >>> +              if (!last_field_info.IsBitfield()) {
> >>> +                // The last field was not a bit-field...
> >>> +                // but if it did take up the entire word then we need to extend
> >>> +                // last_field_end so the bit-field does not step into the last
> >>> +                // fields padding.
> >>> +                if (last_field_end != 0 && ((last_field_end % word_width) != 0))
> >>> +                  last_field_end += word_width - (last_field_end % word_width);
> >>>              }
> >>>
> >>> -              if (anon_field_info.IsValid()) {
> >>> +              // If we have a gap between the last_field_end and the current
> >>> +              // field we have an unnamed bit-field
> >>> +              if (this_field_info.bit_offset != last_field_end &&
> >>> +                  !(this_field_info.bit_offset < last_field_end)) {
> >>> +                unnamed_field_info = FieldInfo{};
> >>> +                unnamed_field_info->bit_size =
> >>> +                    this_field_info.bit_offset - last_field_end;
> >>> +                unnamed_field_info->bit_offset = last_field_end;
> >>> +              }
> >>> +
> >>> +              if (unnamed_field_info) {
> >>>                clang::FieldDecl *unnamed_bitfield_decl =
> >>>                    TypeSystemClang::AddFieldToRecordType(
> >>>                        class_clang_type, llvm::StringRef(),
> >>>                        m_ast.GetBuiltinTypeForEncodingAndBitSize(eEncodingSint,
> >>>                                                                  word_width),
> >>> -                        accessibility, anon_field_info.bit_size);
> >>> +                        accessibility, unnamed_field_info->bit_size);
> >>>
> >>>                layout_info.field_offsets.insert(std::make_pair(
> >>> -                    unnamed_bitfield_decl, anon_field_info.bit_offset));
> >>> +                    unnamed_bitfield_decl, unnamed_field_info->bit_offset));
> >>>              }
> >>>            }
> >>> +
> >>>            last_field_info = this_field_info;
> >>> +            last_field_info.SetIsBitfield(true);
> >>>          } else {
> >>> -            last_field_info.Clear();
> >>> +            last_field_info.bit_offset = field_bit_offset;
> >>> +
> >>> +            if (llvm::Optional<uint64_t> clang_type_size =
> >>> +                    member_clang_type.GetByteSize(nullptr)) {
> >>> +              last_field_info.bit_size = *clang_type_size * character_width;
> >>> +            }
> >>> +
> >>> +            last_field_info.SetIsBitfield(false);
> >>>          }
> >>>
> >>> -          CompilerType member_clang_type = member_type->GetLayoutCompilerType();
> >>>          if (!member_clang_type.IsCompleteType())
> >>>            member_clang_type.GetCompleteType();
> >>>
> >>> @@ -2885,7 +2829,7 @@ bool DWARFASTParserClang::ParseChildMembers(
> >>>  if (!parent_die)
> >>>    return false;
> >>>
> >>> -  BitfieldInfo last_field_info;
> >>> +  FieldInfo last_field_info;
> >>>
> >>>  ModuleSP module_sp = parent_die.GetDWARF()->GetObjectFile()->GetModule();
> >>>  TypeSystemClang *ast =
> >>>
> >>> diff  --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.h b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.h
> >>> index 299281876d6c..6cd2dc8bf558 100644
> >>> --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.h
> >>> +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.h
> >>> @@ -170,33 +170,20 @@ class DWARFASTParserClang : public DWARFASTParser {
> >>>  lldb::ModuleSP GetModuleForType(const DWARFDIE &die);
> >>>
> >>> private:
> >>> -  struct BitfieldInfo {
> >>> -    uint64_t bit_size;
> >>> -    uint64_t bit_offset;
> >>> +  struct FieldInfo {
> >>> +    uint64_t bit_size = 0;
> >>> +    uint64_t bit_offset = 0;
> >>> +    bool is_bitfield = false;
> >>>
> >>> -    BitfieldInfo()
> >>> -        : bit_size(LLDB_INVALID_ADDRESS), bit_offset(LLDB_INVALID_ADDRESS) {}
> >>> +    FieldInfo() = default;
> >>>
> >>> -    void Clear() {
> >>> -      bit_size = LLDB_INVALID_ADDRESS;
> >>> -      bit_offset = LLDB_INVALID_ADDRESS;
> >>> -    }
> >>> -
> >>> -    bool IsValid() const {
> >>> -      return (bit_size != LLDB_INVALID_ADDRESS) &&
> >>> -             (bit_offset != LLDB_INVALID_ADDRESS);
> >>> -    }
> >>> +    void SetIsBitfield(bool flag) { is_bitfield = flag; }
> >>> +    bool IsBitfield() { return is_bitfield; }
> >>>
> >>>    bool NextBitfieldOffsetIsValid(const uint64_t next_bit_offset) const {
> >>> -      if (IsValid()) {
> >>> -        // This bitfield info is valid, so any subsequent bitfields must not
> >>> -        // overlap and must be at a higher bit offset than any previous bitfield
> >>> -        // + size.
> >>> -        return (bit_size + bit_offset) <= next_bit_offset;
> >>> -      } else {
> >>> -        // If the this BitfieldInfo is not valid, then any offset isOK
> >>> -        return true;
> >>> -      }
> >>> +      // Any subsequent bitfields must not overlap and must be at a higher
> >>> +      // bit offset than any previous bitfield + size.
> >>> +      return (bit_size + bit_offset) <= next_bit_offset;
> >>>    }
> >>>  };
> >>>
> >>> @@ -208,7 +195,7 @@ class DWARFASTParserClang : public DWARFASTParser {
> >>>                    lldb::AccessType &default_accessibility,
> >>>                    DelayedPropertyList &delayed_properties,
> >>>                    lldb_private::ClangASTImporter::LayoutInfo &layout_info,
> >>> -                    BitfieldInfo &last_field_info);
> >>> +                    FieldInfo &last_field_info);
> >>>
> >>>  bool CompleteRecordType(const DWARFDIE &die, lldb_private::Type *type,
> >>>                          lldb_private::CompilerType &clang_type);
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> lldb-commits mailing list
> >>> lldb-commits at lists.llvm.org
> >>> https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
> >>
>


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