squiid/llvm
1
0
Fork 0
Code Issues Pull requests Activity

[DebugInfo] Explicitly permit addr_size = 0x02 when parsing DWARF data

Browse source 
Current LLVM implementation uses `MCAsmInfo::CodePointerSize` as addr_size when emitting the DWARF data. llvm-dwarfdump, on the other hand, handles `addr_size`s of 4 and 8 properly and considers all other sizes as an error. This works for most of mainline targets except for MSP430 and AVR.

msp430-gcc v8.3.1 emits DWARF32 with addr_size = 4 (DWARF32 does not imply addr_size = 4, 32 refers to internal offset width of 4 bytes) that is handled by llvm-dwarfdump already. Still, emitting 2-byte target pointers on MSP430 seems correct as well (but not for MSP430X that is supported by msp430-gcc but not by LLVM and has 20-bit address space).

This patch make it possible for MSP430 debug info support to be tested with llvm-dwarfdump.

Differential Revision: https://reviews.llvm.org/D82055
This commit is contained in:
Anatoly Trosinenko 2020-06-22 13:08:20 +03:00 committed by Anton Korobeynikov
parent 23063296b5
commit 359fae6eb0
5 changed files with 40 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
llvm/include/llvm/DebugInfo/DWARF/DWARFContext.h
View file

@ -362,6 +362,10 @@ public:
return version == 2 || version == 3 || version == 4 || version == 5;
}
static bool isAddressSizeSupported(unsigned AddressSize) {
return AddressSize == 2 || AddressSize == 4 || AddressSize == 8;
}
std::shared_ptr<DWARFContext> getDWOContext(StringRef AbsolutePath);
const MCRegisterInfo *getRegisterInfo() const { return RegInfo.get(); }

2
llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
View file

@ -300,7 +300,7 @@ bool DWARFUnitHeader::extract(DWARFContext &Context,
TypeOffset < getLength() + getUnitLengthFieldByteSize();
bool LengthOK = debug_info.isValidOffset(getNextUnitOffset() - 1);
bool VersionOK = DWARFContext::isSupportedVersion(getVersion());
bool AddrSizeOK = getAddressByteSize() == 4 || getAddressByteSize() == 8;
bool AddrSizeOK = DWARFContext::isAddressSizeSupported(getAddressByteSize());
if (!LengthOK || !VersionOK || !AddrSizeOK || !TypeOffsetOK)
return false;

2
llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
View file

@ -133,7 +133,7 @@ bool DWARFVerifier::verifyUnitHeader(const DWARFDataExtractor DebugInfoData,
ValidLength = DebugInfoData.isValidOffset(OffsetStart + Length + 3);
ValidVersion = DWARFContext::isSupportedVersion(Version);
ValidAddrSize = AddrSize == 4 || AddrSize == 8;
ValidAddrSize = DWARFContext::isAddressSizeSupported(AddrSize);
if (!ValidLength || !ValidVersion || !ValidAddrSize || !ValidAbbrevOffset ||
!ValidType) {
Success = false;

BIN
llvm/test/DebugInfo/Inputs/dwarfdump-16bit-addr.o Normal file
View file

Binary file not shown.

34
llvm/test/DebugInfo/dwarfdump-16bit-addr.test Normal file
View file

@ -0,0 +1,34 @@
; Test that llvm-dwarfdump can handle DWARF32 v3 with addr_size = 0x02
; Input object file was produced from source containing just "int x;" with
; clang -target avr -gdwarf-3 -c dwarfdump-16bit-addr.c
; REQUIRES: avr-registered-target
; RUN: llvm-dwarfdump --debug-info %S/Inputs/dwarfdump-16bit-addr.o | FileCheck %s
; RUN: llvm-dwarfdump --verify %S/Inputs/dwarfdump-16bit-addr.o
; CHECK: Inputs/dwarfdump-16bit-addr.o: file format elf32-avr
; CHECK: .debug_info contents:
; CHECK: 0x00000000: Compile Unit: length = 0x00000032, format = DWARF32, version = 0x0003, abbr_offset = 0x0000, addr_size = 0x02 (next unit at 0x00000036)
; CHECK: 0x0000000b: DW_TAG_compile_unit
; CHECK: DW_AT_producer ("clang version 10.0.0-4ubuntu1 ")
; CHECK: DW_AT_language (DW_LANG_C99)
; CHECK: DW_AT_name ("dwarfdump-16bit-addr.c")
; CHECK: DW_AT_stmt_list (0x00000000)
; CHECK: DW_AT_comp_dir ("/tmp")
; CHECK: 0x0000001e: DW_TAG_variable
; CHECK: DW_AT_name ("x")
; CHECK: DW_AT_type (0x0000002e "int")
; CHECK: DW_AT_external (0x01)
; CHECK: DW_AT_decl_file ("/tmp{{[/\\]}}dwarfdump-16bit-addr.c")
; CHECK: DW_AT_decl_line (1)
; CHECK: DW_AT_location (DW_OP_addr 0x0)
; CHECK: 0x0000002e: DW_TAG_base_type
; CHECK: DW_AT_name ("int")
; CHECK: DW_AT_encoding (DW_ATE_signed)
; CHECK: DW_AT_byte_size (0x02)
; CHECK: 0x00000035: NULL