Index: lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp =================================================================== --- lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp +++ lldb/source/Plugins/ABI/SysV-x86_64/ABISysV_x86_64.cpp @@ -30,6 +30,8 @@ #include "lldb/Utility/RegisterValue.h" #include "lldb/Utility/Status.h" +#include + using namespace lldb; using namespace lldb_private; @@ -1558,6 +1560,62 @@ return return_valobj_sp; } +// The compiler will faltten the nested aggregate type into single +// layer and push the value to stack +// This helper function will flatten an aggregate type +// and return true if it can be returned in register(s) by value +// return false if the aggregate is in memory +static bool FlattenAggregateType( + ExecutionContext &exe_ctx, + CompilerType &return_compiler_type, + uint32_t data_byte_offset, + std::vector &aggregate_field_offsets, + std::vector &aggregate_compiler_types) { + const uint32_t num_children = return_compiler_type.GetNumFields(); + for (uint32_t idx = 0; idx < num_children; ++idx) { + std::string name; + bool is_signed; + uint32_t count; + bool is_complex; + + const bool transparent_pointers = false; + const bool omit_empty_base_classes = true; + const bool ignore_array_bounds = false; + uint32_t child_byte_size = 0; + int32_t child_byte_offset = 0; + uint32_t child_bitfield_bit_size = 0; + uint32_t child_bitfield_bit_offset = 0; + bool child_is_base_class = false; + bool child_is_deref_of_parent = false; + uint64_t language_flags; + CompilerType field_compiler_type = + return_compiler_type.GetChildCompilerTypeAtIndex( + &exe_ctx, idx, transparent_pointers, omit_empty_base_classes, + ignore_array_bounds, name, child_byte_size, child_byte_offset, + child_bitfield_bit_size, child_bitfield_bit_offset, + child_is_base_class, child_is_deref_of_parent, nullptr, + language_flags); + + const uint64_t field_bit_offset = child_byte_offset * 8; + uint32_t field_byte_offset = field_bit_offset / 8 + data_byte_offset; + + const uint32_t field_type_flags = field_compiler_type.GetTypeInfo(); + if (field_compiler_type.IsIntegerOrEnumerationType(is_signed) || + field_compiler_type.IsPointerType() || + field_compiler_type.IsFloatingPointType(count, is_complex)) { + aggregate_field_offsets.push_back(field_byte_offset); + aggregate_compiler_types.push_back(field_compiler_type); + } else if (field_type_flags & eTypeHasChildren) { + if (!FlattenAggregateType(exe_ctx, field_compiler_type, + field_byte_offset, aggregate_field_offsets, + aggregate_compiler_types)) { + return false; + } + } + } + return true; +} + ValueObjectSP ABISysV_x86_64::GetReturnValueObjectImpl( Thread &thread, CompilerType &return_compiler_type) const { ValueObjectSP return_valobj_sp; @@ -1580,10 +1638,14 @@ if (return_compiler_type.IsAggregateType()) { Target *target = exe_ctx.GetTargetPtr(); bool is_memory = true; - if (*bit_width <= 128) { - ByteOrder target_byte_order = target->GetArchitecture().GetByteOrder(); + std::vector aggregate_field_offsets; + std::vector aggregate_compiler_types; + if (*bit_width <= 128 && FlattenAggregateType(exe_ctx, return_compiler_type, + 0, aggregate_field_offsets, + aggregate_compiler_types)) { + ByteOrder byte_order = target->GetArchitecture().GetByteOrder(); DataBufferSP data_sp(new DataBufferHeap(16, 0)); - DataExtractor return_ext(data_sp, target_byte_order, + DataExtractor return_ext(data_sp, byte_order, target->GetArchitecture().GetAddressByteSize()); const RegisterInfo *rax_info = @@ -1613,40 +1675,27 @@ uint32_t integer_bytes = 0; // Tracks how much of the rax/rds registers we've consumed so far - const uint32_t num_children = return_compiler_type.GetNumFields(); + // const uint32_t num_children = return_compiler_type.GetNumFields(); + const uint32_t num_children = aggregate_compiler_types.size(); // Since we are in the small struct regime, assume we are not in memory. is_memory = false; - for (uint32_t idx = 0; idx < num_children; idx++) { - std::string name; - uint64_t field_bit_offset = 0; bool is_signed; - bool is_complex; uint32_t count; + bool is_complex; - CompilerType field_compiler_type = return_compiler_type.GetFieldAtIndex( - idx, name, &field_bit_offset, nullptr, nullptr); - llvm::Optional field_bit_width = - field_compiler_type.GetBitSize(&thread); - - // if we don't know the size of the field (e.g. invalid type), just - // bail out - if (!field_bit_width || *field_bit_width == 0) - break; - - // If there are any unaligned fields, this is stored in memory. - if (field_bit_offset % *field_bit_width != 0) { - is_memory = true; - break; - } + CompilerType field_compiler_type = aggregate_compiler_types[idx]; + uint32_t field_byte_width = (uint32_t) (*field_compiler_type.GetByteSize(&thread)); + uint32_t field_byte_offset = aggregate_field_offsets[idx]; - uint32_t field_byte_width = *field_bit_width / 8; - uint32_t field_byte_offset = field_bit_offset / 8; + uint32_t field_bit_width = field_byte_width * 8; DataExtractor *copy_from_extractor = nullptr; uint32_t copy_from_offset = 0; + const uint32_t field_type_flags = field_compiler_type.GetTypeInfo(); + if (field_compiler_type.IsIntegerOrEnumerationType(is_signed) || field_compiler_type.IsPointerType()) { if (integer_bytes < 8) { @@ -1674,10 +1723,10 @@ } } else if (field_compiler_type.IsFloatingPointType(count, is_complex)) { // Structs with long doubles are always passed in memory. - if (*field_bit_width == 128) { + if (field_bit_width == 128) { is_memory = true; break; - } else if (*field_bit_width == 64) { + } else if (field_bit_width == 64) { // These have to be in a single xmm register. if (fp_bytes == 0) copy_from_extractor = &xmm0_data; @@ -1686,7 +1735,7 @@ copy_from_offset = 0; fp_bytes += field_byte_width; - } else if (*field_bit_width == 32) { + } else if (field_bit_width == 32) { // This one is kind of complicated. If we are in an "eightbyte" // with another float, we'll be stuffed into an xmm register with // it. If we are in an "eightbyte" with one or more ints, then we @@ -1695,18 +1744,15 @@ if (field_byte_offset % 8 == 0) { // We are at the beginning of one of the eightbytes, so check the // next element (if any) - if (idx == num_children - 1) + if (idx == num_children - 1) { in_gpr = false; - else { - uint64_t next_field_bit_offset = 0; + } else { CompilerType next_field_compiler_type = - return_compiler_type.GetFieldAtIndex(idx + 1, name, - &next_field_bit_offset, - nullptr, nullptr); + aggregate_compiler_types[idx + 1]; if (next_field_compiler_type.IsIntegerOrEnumerationType( - is_signed)) + is_signed)) { in_gpr = true; - else { + } else { copy_from_offset = 0; in_gpr = false; } @@ -1715,18 +1761,15 @@ // We are inside of an eightbyte, so see if the field before us // is floating point: This could happen if somebody put padding // in the structure. - if (idx == 0) + if (idx == 0) { in_gpr = false; - else { - uint64_t prev_field_bit_offset = 0; + } else { CompilerType prev_field_compiler_type = - return_compiler_type.GetFieldAtIndex(idx - 1, name, - &prev_field_bit_offset, - nullptr, nullptr); + aggregate_compiler_types[idx - 1]; if (prev_field_compiler_type.IsIntegerOrEnumerationType( - is_signed)) + is_signed)) { in_gpr = true; - else { + } else { copy_from_offset = 4; in_gpr = false; } @@ -1759,22 +1802,21 @@ } } } - // These two tests are just sanity checks. If I somehow get the type // calculation wrong above it is better to just return nothing than to // assert or crash. - if (!copy_from_extractor) + if (!copy_from_extractor) { return return_valobj_sp; + } if (copy_from_offset + field_byte_width > - copy_from_extractor->GetByteSize()) + copy_from_extractor->GetByteSize()) { return return_valobj_sp; - + } copy_from_extractor->CopyByteOrderedData( copy_from_offset, field_byte_width, data_sp->GetBytes() + field_byte_offset, field_byte_width, - target_byte_order); + byte_order); } - if (!is_memory) { // The result is in our data buffer. Let's make a variable object out // of it: