From e8ead0fbb291e08d73de55fd84c330f1d7e3dba9 Mon Sep 17 00:00:00 2001 From: Esme-Yi Date: Tue, 27 Jul 2021 07:28:59 +0000 Subject: [PATCH] [Debug-Info][llvm-dwarfdump] Don't try to dump location list for attributes that don't have the loclist class. Summary: The overflow error occurs when we try to dump location list for those attributes that do not have the loclist class, like DW_AT_count and DW_AT_byte_size. After re-reviewed the entire list, I sorted those attributes into two parts, one for dumping location list and one for dumping the location expression. Reviewed By: probinson Differential Revision: https://reviews.llvm.org/D105613 --- include/llvm/DebugInfo/DWARF/DWARFAttribute.h | 5 +- lib/DWARFLinker/DWARFLinker.cpp | 2 +- lib/DebugInfo/DWARF/DWARFDie.cpp | 95 +++++++---- test/tools/llvm-dwarfdump/X86/formclass3.s | 149 ++++++++++++++++++ 4 files changed, 216 insertions(+), 35 deletions(-) create mode 100644 test/tools/llvm-dwarfdump/X86/formclass3.s diff --git a/include/llvm/DebugInfo/DWARF/DWARFAttribute.h b/include/llvm/DebugInfo/DWARF/DWARFAttribute.h index 66be921efa2..104ac1b9ddf 100644 --- a/include/llvm/DebugInfo/DWARF/DWARFAttribute.h +++ b/include/llvm/DebugInfo/DWARF/DWARFAttribute.h @@ -39,9 +39,12 @@ struct DWARFAttribute { return isValid(); } + /// Identify DWARF attributes that may contain a pointer to a location list. + static bool mayHaveLocationList(dwarf::Attribute Attr); + /// Identifies DWARF attributes that may contain a reference to a /// DWARF expression. - static bool mayHaveLocationDescription(dwarf::Attribute Attr); + static bool mayHaveLocationExpr(dwarf::Attribute Attr); }; } // end namespace llvm diff --git a/lib/DWARFLinker/DWARFLinker.cpp b/lib/DWARFLinker/DWARFLinker.cpp index 58dd5918d4b..4449cd8ef55 100644 --- a/lib/DWARFLinker/DWARFLinker.cpp +++ b/lib/DWARFLinker/DWARFLinker.cpp @@ -1029,7 +1029,7 @@ unsigned DWARFLinker::DIECloner::cloneBlockAttribute( // buffer using cloneExpression(), otherwise copy the data directly. SmallVector Buffer; ArrayRef Bytes = *Val.getAsBlock(); - if (DWARFAttribute::mayHaveLocationDescription(AttrSpec.Attr) && + if (DWARFAttribute::mayHaveLocationExpr(AttrSpec.Attr) && (Val.isFormClass(DWARFFormValue::FC_Block) || Val.isFormClass(DWARFFormValue::FC_Exprloc))) { DWARFUnit &OrigUnit = Unit.getOrigUnit(); diff --git a/lib/DebugInfo/DWARF/DWARFDie.cpp b/lib/DebugInfo/DWARF/DWARFDie.cpp index d82de9fefa6..0501e3ee3f9 100644 --- a/lib/DebugInfo/DWARF/DWARFDie.cpp +++ b/lib/DebugInfo/DWARF/DWARFDie.cpp @@ -69,39 +69,43 @@ static void dumpRanges(const DWARFObject &Obj, raw_ostream &OS, } } -static void dumpLocation(raw_ostream &OS, const DWARFFormValue &FormValue, - DWARFUnit *U, unsigned Indent, - DIDumpOptions DumpOpts) { +static void dumpLocationList(raw_ostream &OS, const DWARFFormValue &FormValue, + DWARFUnit *U, unsigned Indent, + DIDumpOptions DumpOpts) { + assert(FormValue.isFormClass(DWARFFormValue::FC_SectionOffset) && + "bad FORM for location list"); DWARFContext &Ctx = U->getContext(); const MCRegisterInfo *MRI = Ctx.getRegisterInfo(); - if (FormValue.isFormClass(DWARFFormValue::FC_Block) || - FormValue.isFormClass(DWARFFormValue::FC_Exprloc)) { - ArrayRef Expr = *FormValue.getAsBlock(); - DataExtractor Data(StringRef((const char *)Expr.data(), Expr.size()), - Ctx.isLittleEndian(), 0); - DWARFExpression(Data, U->getAddressByteSize(), U->getFormParams().Format) - .print(OS, DumpOpts, MRI, U); - return; + uint64_t Offset = *FormValue.getAsSectionOffset(); + + if (FormValue.getForm() == DW_FORM_loclistx) { + FormValue.dump(OS, DumpOpts); + + if (auto LoclistOffset = U->getLoclistOffset(Offset)) + Offset = *LoclistOffset; + else + return; } + U->getLocationTable().dumpLocationList(&Offset, OS, U->getBaseAddress(), MRI, + Ctx.getDWARFObj(), U, DumpOpts, + Indent); + return; +} - if (FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) { - uint64_t Offset = *FormValue.getAsSectionOffset(); - - if (FormValue.getForm() == DW_FORM_loclistx) { - FormValue.dump(OS, DumpOpts); - - if (auto LoclistOffset = U->getLoclistOffset(Offset)) - Offset = *LoclistOffset; - else - return; - } - U->getLocationTable().dumpLocationList(&Offset, OS, U->getBaseAddress(), - MRI, Ctx.getDWARFObj(), U, DumpOpts, - Indent); - return; - } - - FormValue.dump(OS, DumpOpts); +static void dumpLocationExpr(raw_ostream &OS, const DWARFFormValue &FormValue, + DWARFUnit *U, unsigned Indent, + DIDumpOptions DumpOpts) { + assert((FormValue.isFormClass(DWARFFormValue::FC_Block) || + FormValue.isFormClass(DWARFFormValue::FC_Exprloc)) && + "bad FORM for location expression"); + DWARFContext &Ctx = U->getContext(); + const MCRegisterInfo *MRI = Ctx.getRegisterInfo(); + ArrayRef Expr = *FormValue.getAsBlock(); + DataExtractor Data(StringRef((const char *)Expr.data(), Expr.size()), + Ctx.isLittleEndian(), 0); + DWARFExpression(Data, U->getAddressByteSize(), U->getFormParams().Format) + .print(OS, DumpOpts, MRI, U); + return; } /// Dump the name encoded in the type tag. @@ -289,9 +293,15 @@ static void dumpAttribute(raw_ostream &OS, const DWARFDie &Die, else FormValue.dump(OS, DumpOpts); } - } else if (Form == dwarf::Form::DW_FORM_exprloc || - DWARFAttribute::mayHaveLocationDescription(Attr)) - dumpLocation(OS, FormValue, U, sizeof(BaseIndent) + Indent + 4, DumpOpts); + } else if (DWARFAttribute::mayHaveLocationList(Attr) && + FormValue.isFormClass(DWARFFormValue::FC_SectionOffset)) + dumpLocationList(OS, FormValue, U, sizeof(BaseIndent) + Indent + 4, + DumpOpts); + else if (FormValue.isFormClass(DWARFFormValue::FC_Exprloc) || + (DWARFAttribute::mayHaveLocationExpr(Attr) && + FormValue.isFormClass(DWARFFormValue::FC_Block))) + dumpLocationExpr(OS, FormValue, U, sizeof(BaseIndent) + Indent + 4, + DumpOpts); else FormValue.dump(OS, DumpOpts); @@ -744,11 +754,29 @@ DWARFDie::attribute_iterator &DWARFDie::attribute_iterator::operator++() { return *this; } -bool DWARFAttribute::mayHaveLocationDescription(dwarf::Attribute Attr) { +bool DWARFAttribute::mayHaveLocationList(dwarf::Attribute Attr) { + switch(Attr) { + case DW_AT_location: + case DW_AT_string_length: + case DW_AT_return_addr: + case DW_AT_data_member_location: + case DW_AT_frame_base: + case DW_AT_static_link: + case DW_AT_segment: + case DW_AT_use_location: + case DW_AT_vtable_elem_location: + return true; + default: + return false; + } +} + +bool DWARFAttribute::mayHaveLocationExpr(dwarf::Attribute Attr) { switch (Attr) { // From the DWARF v5 specification. case DW_AT_location: case DW_AT_byte_size: + case DW_AT_bit_offset: case DW_AT_bit_size: case DW_AT_string_length: case DW_AT_lower_bound: @@ -764,6 +792,7 @@ bool DWARFAttribute::mayHaveLocationDescription(dwarf::Attribute Attr) { case DW_AT_vtable_elem_location: case DW_AT_allocated: case DW_AT_associated: + case DW_AT_data_location: case DW_AT_byte_stride: case DW_AT_rank: case DW_AT_call_value: diff --git a/test/tools/llvm-dwarfdump/X86/formclass3.s b/test/tools/llvm-dwarfdump/X86/formclass3.s new file mode 100644 index 00000000000..cc7ed83fac5 --- /dev/null +++ b/test/tools/llvm-dwarfdump/X86/formclass3.s @@ -0,0 +1,149 @@ +# Source: +# unsigned char arr[0x100000]; +# Compile with: +# clang -O2 -gdwarf-3 -S 1.cpp -o 1.s --target=x86_64-pc-linux-gnu + +# RUN: llvm-mc -triple x86_64-pc-linux-gnu -o - -filetype obj < %s | \ +# RUN: llvm-dwarfdump -debug-info - | FileCheck %s + +# CHECK: DW_AT_count (0x00100000) + + .text + .file "1.cpp" + .file 1 "/llvm-project" "1.cpp" + .type arr,@object # @arr + .bss + .globl arr + .p2align 4 +arr: + .zero 1048576 + .size arr, 1048576 + + .section .debug_abbrev,"",@progbits + .byte 1 # Abbreviation Code + .byte 17 # DW_TAG_compile_unit + .byte 1 # DW_CHILDREN_yes + .byte 37 # DW_AT_producer + .byte 14 # DW_FORM_strp + .byte 19 # DW_AT_language + .byte 5 # DW_FORM_data2 + .byte 3 # DW_AT_name + .byte 14 # DW_FORM_strp + .byte 16 # DW_AT_stmt_list + .byte 6 # DW_FORM_data4 + .byte 27 # DW_AT_comp_dir + .byte 14 # DW_FORM_strp + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 2 # Abbreviation Code + .byte 52 # DW_TAG_variable + .byte 0 # DW_CHILDREN_no + .byte 3 # DW_AT_name + .byte 14 # DW_FORM_strp + .byte 73 # DW_AT_type + .byte 19 # DW_FORM_ref4 + .byte 63 # DW_AT_external + .byte 12 # DW_FORM_flag + .byte 58 # DW_AT_decl_file + .byte 11 # DW_FORM_data1 + .byte 59 # DW_AT_decl_line + .byte 11 # DW_FORM_data1 + .byte 2 # DW_AT_location + .byte 10 # DW_FORM_block1 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 3 # Abbreviation Code + .byte 1 # DW_TAG_array_type + .byte 1 # DW_CHILDREN_yes + .byte 73 # DW_AT_type + .byte 19 # DW_FORM_ref4 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 4 # Abbreviation Code + .byte 33 # DW_TAG_subrange_type + .byte 0 # DW_CHILDREN_no + .byte 73 # DW_AT_type + .byte 19 # DW_FORM_ref4 + .byte 55 # DW_AT_count + .byte 6 # DW_FORM_data4 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 5 # Abbreviation Code + .byte 36 # DW_TAG_base_type + .byte 0 # DW_CHILDREN_no + .byte 3 # DW_AT_name + .byte 14 # DW_FORM_strp + .byte 62 # DW_AT_encoding + .byte 11 # DW_FORM_data1 + .byte 11 # DW_AT_byte_size + .byte 11 # DW_FORM_data1 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 6 # Abbreviation Code + .byte 36 # DW_TAG_base_type + .byte 0 # DW_CHILDREN_no + .byte 3 # DW_AT_name + .byte 14 # DW_FORM_strp + .byte 11 # DW_AT_byte_size + .byte 11 # DW_FORM_data1 + .byte 62 # DW_AT_encoding + .byte 11 # DW_FORM_data1 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 0 # EOM(3) + .section .debug_info,"",@progbits +.Lcu_begin0: + .long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit +.Ldebug_info_start0: + .short 3 # DWARF version number + .long .debug_abbrev # Offset Into Abbrev. Section + .byte 8 # Address Size (in bytes) + .byte 1 # Abbrev [1] 0xb:0x47 DW_TAG_compile_unit + .long .Linfo_string0 # DW_AT_producer + .short 33 # DW_AT_language + .long .Linfo_string1 # DW_AT_name + .long .Lline_table_start0 # DW_AT_stmt_list + .long .Linfo_string2 # DW_AT_comp_dir + .byte 2 # Abbrev [2] 0x1e:0x16 DW_TAG_variable + .long .Linfo_string3 # DW_AT_name + .long 52 # DW_AT_type + .byte 1 # DW_AT_external + .byte 1 # DW_AT_decl_file + .byte 1 # DW_AT_decl_line + .byte 9 # DW_AT_location + .byte 3 + .quad arr + .byte 3 # Abbrev [3] 0x34:0xf DW_TAG_array_type + .long 67 # DW_AT_type + .byte 4 # Abbrev [4] 0x39:0x9 DW_TAG_subrange_type + .long 74 # DW_AT_type + .long 1048576 # DW_AT_count + .byte 0 # End Of Children Mark + .byte 5 # Abbrev [5] 0x43:0x7 DW_TAG_base_type + .long .Linfo_string4 # DW_AT_name + .byte 8 # DW_AT_encoding + .byte 1 # DW_AT_byte_size + .byte 6 # Abbrev [6] 0x4a:0x7 DW_TAG_base_type + .long .Linfo_string5 # DW_AT_name + .byte 8 # DW_AT_byte_size + .byte 7 # DW_AT_encoding + .byte 0 # End Of Children Mark +.Ldebug_info_end0: + .section .debug_str,"MS",@progbits,1 +.Linfo_string0: + .asciz "clang version 13.0.0" # string offset=0 +.Linfo_string1: + .asciz "1.cpp" # string offset=21 +.Linfo_string2: + .asciz "/llvm-project" # string offset=27 +.Linfo_string3: + .asciz "arr" # string offset=61 +.Linfo_string4: + .asciz "unsigned char" # string offset=65 +.Linfo_string5: + .asciz "__ARRAY_SIZE_TYPE__" # string offset=79 + .ident "clang version 13.0.0" + .section ".note.GNU-stack","",@progbits + .addrsig + .section .debug_line,"",@progbits +.Lline_table_start0: