nicolas/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Thread Expected<...> up from libObject’s getName() for symbols to allow llvm-objdump to produce a good error message.

Browse Source 
Produce another specific error message for a malformed Mach-O file when a symbol’s
string index is past the end of the string table.  The existing test case in test/Object/macho-invalid.test
for macho-invalid-symbol-name-past-eof now reports the error with the message indicating
that a symbol at a specific index has a bad sting index and that bad string index value.
 
Again converting interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. Where the existing code reported the error with a
string message or an error code it was converted to do the same.  There is some
code for this that could be factored into a routine but I would like to leave that for
the code owners post-commit to do as they want for handling an llvm::Error.  An
example of how this could be done is shown in the diff in
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h which had a Check() routine
already for std::error_code so I added one like it for llvm::Error .

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(NameOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there fixes needed to lld that goes along with this that I will commit right after this.
So expect lld not to built after this commit and before the next one.

llvm-svn: 266919
This commit is contained in:
Kevin Enderby
2016-04-20 21:24:34 +00:00
parent 64d4e2bc0d
commit 81e8b7d949
39 changed files with 436 additions and 190 deletions
Download Patch File Download Diff File Expand all files Collapse all files

27
llvm/lib/Object/MachOObjectFile.cpp
View File

@@ -46,12 +46,11 @@ malformedError(std::string FileName, std::string Msg,
ECOverride);
}
// FIXME: Remove ECOverride once Error has been plumbed down to obj tool code.
static Error
malformedError(const MachOObjectFile &Obj, std::string Msg,
malformedError(const MachOObjectFile &Obj, Twine Msg,
object_error ECOverride = object_error::parse_failed) {
return malformedError(Obj.getFileName(), std::move(Msg), ECOverride);
return malformedError(Obj.getFileName(), std::move(Msg.str()), ECOverride);
}
// FIXME: Replace all uses of this function with getStructOrErr.
@@ -444,12 +443,16 @@ void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
Symb.p += SymbolTableEntrySize;
}
ErrorOr<StringRef> MachOObjectFile::getSymbolName(DataRefImpl Symb) const {
Expected<StringRef> MachOObjectFile::getSymbolName(DataRefImpl Symb) const {
StringRef StringTable = getStringTableData();
MachO::nlist_base Entry = getSymbolTableEntryBase(this, Symb);
const char *Start = &StringTable.data()[Entry.n_strx];
if (Start < getData().begin() || Start >= getData().end())
return object_error::parse_failed;
if (Start < getData().begin() || Start >= getData().end()) {
return malformedError(*this, Twine("truncated or malformed object (bad "
"string index: ") + Twine(Entry.n_strx) + Twine(" for "
"symbol at index ") + Twine(getSymbolIndex(Symb)) +
Twine(")"));
}
return StringRef(Start);
}
@@ -1108,6 +1111,18 @@ basic_symbol_iterator MachOObjectFile::getSymbolByIndex(unsigned Index) const {
return basic_symbol_iterator(SymbolRef(DRI, this));
}
uint64_t MachOObjectFile::getSymbolIndex(DataRefImpl Symb) const {
MachO::symtab_command Symtab = getSymtabLoadCommand();
if (!SymtabLoadCmd)
report_fatal_error("getSymbolIndex() called with no symbol table symbol");
unsigned SymbolTableEntrySize =
is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
DataRefImpl DRIstart;
DRIstart.p = reinterpret_cast<uintptr_t>(getPtr(this, Symtab.symoff));
uint64_t Index = (Symb.p - DRIstart.p) / SymbolTableEntrySize;
return Index;
}
section_iterator MachOObjectFile::section_begin() const {
DataRefImpl DRI;
return section_iterator(SectionRef(DRI, this));