llvm-project/llvm
Greg Clayton 3462a420d1 Make a DWARF generator so we can unit test DWARF APIs with gtest.
The only tests we have for the DWARF parser are the tests that use llvm-dwarfdump and expect output from textual dumps.

More DWARF parser modification are coming in the next few weeks and I wanted to add tests that can verify that we can encode and decode all form types, as well as test some other basic DWARF APIs where we ask DIE objects for their children and siblings.

DwarfGenerator.cpp was added in the lib/CodeGen directory. This file contains the code necessary to easily create DWARF for tests:

dwarfgen::Generator DG;
Triple Triple("x86_64--");
bool success = DG.init(Triple, Version);
if (!success)
  return;
dwarfgen::CompileUnit &CU = DG.addCompileUnit();
dwarfgen::DIE CUDie = CU.getUnitDIE();

CUDie.addAttribute(DW_AT_name, DW_FORM_strp, "/tmp/main.c");
CUDie.addAttribute(DW_AT_language, DW_FORM_data2, DW_LANG_C);

dwarfgen::DIE SubprogramDie = CUDie.addChild(DW_TAG_subprogram);
SubprogramDie.addAttribute(DW_AT_name, DW_FORM_strp, "main");
SubprogramDie.addAttribute(DW_AT_low_pc, DW_FORM_addr, 0x1000U);
SubprogramDie.addAttribute(DW_AT_high_pc, DW_FORM_addr, 0x2000U);

dwarfgen::DIE IntDie = CUDie.addChild(DW_TAG_base_type);
IntDie.addAttribute(DW_AT_name, DW_FORM_strp, "int");
IntDie.addAttribute(DW_AT_encoding, DW_FORM_data1, DW_ATE_signed);
IntDie.addAttribute(DW_AT_byte_size, DW_FORM_data1, 4);

dwarfgen::DIE ArgcDie = SubprogramDie.addChild(DW_TAG_formal_parameter);
ArgcDie.addAttribute(DW_AT_name, DW_FORM_strp, "argc");
// ArgcDie.addAttribute(DW_AT_type, DW_FORM_ref4, IntDie);
ArgcDie.addAttribute(DW_AT_type, DW_FORM_ref_addr, IntDie);

StringRef FileBytes = DG.generate();
MemoryBufferRef FileBuffer(FileBytes, "dwarf");
auto Obj = object::ObjectFile::createObjectFile(FileBuffer);
EXPECT_TRUE((bool)Obj);
DWARFContextInMemory DwarfContext(*Obj.get());
This code is backed by the AsmPrinter code that emits DWARF for the actual compiler.

While adding unit tests it was discovered that DIEValue that used DIEEntry as their values had bugs where DW_FORM_ref1, DW_FORM_ref2, DW_FORM_ref8, and DW_FORM_ref_udata forms were not supported. These are all now supported. Added support for DW_FORM_string so we can emit inlined C strings.

Centralized the code to unique abbreviations into a new DIEAbbrevSet class and made both the dwarfgen::Generator and the llvm::DwarfFile classes use the new class.

Fixed comments in the llvm::DIE class so that the Offset is known to be the compile/type unit offset.

DIEInteger now supports more DW_FORM values.

There are also unit tests that cover:

Encoding and decoding all form types and values
Encoding and decoding all reference types (DW_FORM_ref1, DW_FORM_ref2, DW_FORM_ref4, DW_FORM_ref8, DW_FORM_ref_udata, DW_FORM_ref_addr) including cross compile unit references with that go forward one compile unit and backward on compile unit.

Differential Revision: https://reviews.llvm.org/D27326

llvm-svn: 289010
2016-12-08 01:03:48 +00:00
..
bindings Fix go binding to adapt the new attribute API 2016-11-18 10:11:02 +00:00
cmake [CMake] Add check for HAVE_CRASHREPORTER_INFO 2016-12-07 20:55:38 +00:00
docs [doc] Add .arcconfig setup to the "how to work with a monorepo" section 2016-12-03 01:04:40 +00:00
examples ExceptionDemo: remove some undefined behaviour 2016-11-20 02:36:38 +00:00
include Make a DWARF generator so we can unit test DWARF APIs with gtest. 2016-12-08 01:03:48 +00:00
lib Make a DWARF generator so we can unit test DWARF APIs with gtest. 2016-12-08 01:03:48 +00:00
projects
resources
runtimes [CMake] Make the runtimes directory work with bootstrap builds 2016-10-19 21:50:25 +00:00
test CFI-icall on Thumb 2016-12-08 00:32:26 +00:00
tools [yaml2obj] Refactor and abstract yaml2dwarf functions 2016-12-07 22:30:15 +00:00
unittests Make a DWARF generator so we can unit test DWARF APIs with gtest. 2016-12-08 01:03:48 +00:00
utils Summary: Currently there is no way to disable deprecated warning from asm like this 2016-12-05 23:55:13 +00:00
.arcconfig
.clang-format
.clang-tidy
.gitignore
CMakeLists.txt [CMake] Fixing clang standalone build 2016-12-06 17:09:29 +00:00
CODE_OWNERS.TXT CODE_OWNERS: Take ownership of IR Linker as discussed on llvm-dev 2016-12-02 14:06:53 +00:00
CREDITS.TXT Test Commit, removing a blank line in CREDITS.TXT 2016-11-24 15:40:19 +00:00
LICENSE.TXT
LLVMBuild.txt
README.txt Test commit, deleted empty line at the end of README.txt 2016-11-07 18:31:21 +00:00
RELEASE_TESTERS.TXT
configure
llvm.spec.in

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