Author: David Spickett Date: 2024-07-03T14:30:47+01:00 New Revision: dde3f17026be48c05a5d3876f12db72fdd6422ed
URL: https://github.com/llvm/llvm-project/commit/dde3f17026be48c05a5d3876f12db72fdd6422ed DIFF: https://github.com/llvm/llvm-project/commit/dde3f17026be48c05a5d3876f12db72fdd6422ed.diff LOG: [lldb] Fix printing of unsigned enum bitfields when they contain the max value (#96202) While testing register fields I found that if you put the max value into a bitfield with an underlying type that is an unsigned enum, lldb would not print the enum name. This is because the code to match values to names wasn't checking whether the enum's type was signed, it just assumed it was. So for example a 2 bit field with value 3 got signed extended to -1, which didn't match the enumerator value of 3. So lldb just printed the number instead of the name. For a value of 1, the top bit was 0 so the sign extend became a zero extend, and lldb did print the name of the enumerator. I added a new test because I needed to use C++ to get typed enums. It checks min, max and an in between value for signed and unsigned enums applied to a bitfield. Added: lldb/test/API/commands/expression/bitfield_enums/Makefile lldb/test/API/commands/expression/bitfield_enums/TestBitfieldEnums.py lldb/test/API/commands/expression/bitfield_enums/main.cpp Modified: lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp Removed: ################################################################################ diff --git a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp index 093d27a92d718..e0fbb32b30b20 100644 --- a/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp +++ b/lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp @@ -8639,8 +8639,13 @@ static bool DumpEnumValue(const clang::QualType &qual_type, Stream &s, const clang::EnumDecl *enum_decl = enutype->getDecl(); assert(enum_decl); lldb::offset_t offset = byte_offset; - const uint64_t enum_svalue = data.GetMaxS64Bitfield( - &offset, byte_size, bitfield_bit_size, bitfield_bit_offset); + bool qual_type_is_signed = qual_type->isSignedIntegerOrEnumerationType(); + const uint64_t enum_svalue = + qual_type_is_signed + ? data.GetMaxS64Bitfield(&offset, byte_size, bitfield_bit_size, + bitfield_bit_offset) + : data.GetMaxU64Bitfield(&offset, byte_size, bitfield_bit_size, + bitfield_bit_offset); bool can_be_bitfield = true; uint64_t covered_bits = 0; int num_enumerators = 0; @@ -8652,8 +8657,11 @@ static bool DumpEnumValue(const clang::QualType &qual_type, Stream &s, // enumerators. Also 0 doesn't make sense when the enumerators are used as // flags. for (auto *enumerator : enum_decl->enumerators()) { - uint64_t val = enumerator->getInitVal().getSExtValue(); - val = llvm::SignExtend64(val, 8*byte_size); + llvm::APSInt init_val = enumerator->getInitVal(); + uint64_t val = + qual_type_is_signed ? init_val.getSExtValue() : init_val.getZExtValue(); + if (qual_type_is_signed) + val = llvm::SignExtend64(val, 8 * byte_size); if (llvm::popcount(val) != 1 && (val & ~covered_bits) != 0) can_be_bitfield = false; covered_bits |= val; @@ -8673,7 +8681,7 @@ static bool DumpEnumValue(const clang::QualType &qual_type, Stream &s, // No exact match, but we don't think this is a bitfield. Print the value as // decimal. if (!can_be_bitfield) { - if (qual_type->isSignedIntegerOrEnumerationType()) + if (qual_type_is_signed) s.Printf("%" PRIi64, enum_svalue); else s.Printf("%" PRIu64, enum_uvalue); diff --git a/lldb/test/API/commands/expression/bitfield_enums/Makefile b/lldb/test/API/commands/expression/bitfield_enums/Makefile new file mode 100644 index 0000000000000..99998b20bcb05 --- /dev/null +++ b/lldb/test/API/commands/expression/bitfield_enums/Makefile @@ -0,0 +1,3 @@ +CXX_SOURCES := main.cpp + +include Makefile.rules diff --git a/lldb/test/API/commands/expression/bitfield_enums/TestBitfieldEnums.py b/lldb/test/API/commands/expression/bitfield_enums/TestBitfieldEnums.py new file mode 100644 index 0000000000000..a484b69300e7b --- /dev/null +++ b/lldb/test/API/commands/expression/bitfield_enums/TestBitfieldEnums.py @@ -0,0 +1,31 @@ +""" +Test that the expression parser accounts for the underlying type of bitfield +enums when looking for matching values. +""" + +import lldb +from lldbsuite.test.decorators import * +from lldbsuite.test.lldbtest import * +from lldbsuite.test import lldbutil + + +class TestBitfieldEnum(TestBase): + def test_bitfield_enums(self): + self.build() + + lldbutil.run_to_source_breakpoint( + self, "// break here", lldb.SBFileSpec("main.cpp", False) + ) + + self.expect_expr( + "bfs", + result_type="BitfieldStruct", + result_children=[ + ValueCheck(name="signed_min", value="min"), + ValueCheck(name="signed_other", value="-1"), + ValueCheck(name="signed_max", value="max"), + ValueCheck(name="unsigned_min", value="min"), + ValueCheck(name="unsigned_other", value="1"), + ValueCheck(name="unsigned_max", value="max"), + ], + ) diff --git a/lldb/test/API/commands/expression/bitfield_enums/main.cpp b/lldb/test/API/commands/expression/bitfield_enums/main.cpp new file mode 100644 index 0000000000000..f6c53b3100b93 --- /dev/null +++ b/lldb/test/API/commands/expression/bitfield_enums/main.cpp @@ -0,0 +1,24 @@ +enum class SignedEnum : int { min = -2, max = 1 }; +enum class UnsignedEnum : unsigned { min = 0, max = 3 }; + +struct BitfieldStruct { + SignedEnum signed_min : 2; + SignedEnum signed_other : 2; + SignedEnum signed_max : 2; + UnsignedEnum unsigned_min : 2; + UnsignedEnum unsigned_other : 2; + UnsignedEnum unsigned_max : 2; +}; + +int main() { + BitfieldStruct bfs; + bfs.signed_min = SignedEnum::min; + bfs.signed_other = static_cast<SignedEnum>(-1); + bfs.signed_max = SignedEnum::max; + + bfs.unsigned_min = UnsignedEnum::min; + bfs.unsigned_other = static_cast<UnsignedEnum>(1); + bfs.unsigned_max = UnsignedEnum::max; + + return 0; // break here +} _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
