Commit Graph

42 Commits

Author SHA1 Message Date
Mehdi Amini 16e25c8d4c Fix wrong formatting in lld introduced in r286561 (NFC)
Pointed out by Davide.

llvm-svn: 286649
2016-11-11 22:28:19 +00:00
Mehdi Amini c1edf566b9 Prevent at compile time converting from Error::success() to Expected<T>
This would trigger an assertion at runtime otherwise.

Differential Revision: https://reviews.llvm.org/D26482

llvm-svn: 286562
2016-11-11 04:29:25 +00:00
Pete Cooper 1e00911ee0 Change getReferenceInfo/getPairReferenceInfo to use new Error handling. NFC.
Adds a GenericError class to lld/Core which can carry a string.  This is
analygous to the dynamic_error we currently use in lld/Core.

Use this GenericError instead of make_dynamic_error_code.  Also, provide
an implemention of GenericError::convertToErrorCode which for now converts
it in to the dynamic_error_code we used to have.  This will go away once
all the APIs are converted.

llvm-svn: 264910
2016-03-30 20:15:06 +00:00
Pete Cooper 47e5399cd3 Fix more cases of UB from allocating 0 sized data. NFC.
The size of a section can be zero, even when it contains atoms, so
long as all of the atoms are also size 0.  In this case we were
allocating space for a 0 sized buffer.

Changed this to only allocate when we need the space, but also cleaned
up all the code to use MutableArrayRef instead of uint8_t* so its much much
safer as we get bounds checking on all of our section creation logic.

llvm-svn: 264204
2016-03-23 22:19:16 +00:00
Pete Cooper 8ad55fb2d0 Use owning pointers instead of raw pointers for Atom's to fix leaks.
This is a re-commit of r264022 with a fix for MSVC.  The issue there was
that the code was running DefinedAtom::~Atom() for some value and instead
needed to cast to Atom before running ~Atom.  Original commit message follows.

Currently each File contains an BumpPtrAllocator in which Atom's are
allocated.  Some Atom's contain data structures like std::vector which
leak as we don't run ~Atom when they are BumpPtrAllocate'd.

Now each File actually owns its Atom's using an OwningAtomPtr.  This
is analygous to std::unique_ptr and may be replaced by it if possible.

An Atom can therefore only be owned by a single File, so the Resolver now
moves them from one File to another.  The MachOLinkingContext owns the File's
and so clears all the Atom's in ~MachOLinkingContext, then delete's all the
File's.  This makes sure all Atom's have been destructed before any of the
BumpPtrAllocator's in which they run have gone away.

Should hopefully fix the remaining leaks.  Will keep an eye on the bots to
make sure.

llvm-svn: 264067
2016-03-22 17:15:50 +00:00
Pete Cooper 3e4d732dd0 Revert "Use owning pointers instead of raw pointers for Atom's to fix leaks."
This reverts commit r264022.

This breaks the Window's bots which don't like that i'm calling ~Atom when
the this pointer is a sublcass of Atom.

Reverting for now until I try find a better fix.  I tried using std::unique_ptr with
a custom deleter as a quick fix, but it didn't work well in the YAML parser.

llvm-svn: 264023
2016-03-22 04:00:41 +00:00
Pete Cooper 572a87e2aa Use owning pointers instead of raw pointers for Atom's to fix leaks.
Currently each File contains an BumpPtrAllocator in which Atom's are
allocated.  Some Atom's contain data structures like std::vector which
leak as we don't run ~Atom when they are BumpPtrAllocate'd.

Now each File actually owns its Atom's using an OwningAtomPtr.  This
is analygous to std::unique_ptr and may be replaced by it if possible.

An Atom can therefore only be owned by a single File, so the Resolver now
moves them from one File to another.  The MachOLinkingContext owns the File's
and so clears all the Atom's in ~MachOLinkingContext, then delete's all the
File's.  This makes sure all Atom's have been destructed before any of the
BumpPtrAllocator's in which they run have gone away.

Should hopefully fix the remaining leaks.  Will keep an eye on the bots to
make sure.

llvm-svn: 264022
2016-03-22 03:44:32 +00:00
Pete Cooper ebecd6c543 Fix EHFrame processing to add implicit references when needed.
The current code for processCIE and processFDE returns out if it sees
any references.  The problem with this is that some references could be
explicit in the binary, while others are implicit as they can be
inferred from the content of the EHFrame itself.

This change walks the references we have against the references we
need, and verifies that all explicit references are in the correct place,
and generates any missing implicit ones.

Reviewed by Lang Hames and Nick Kledzik.

Differential Revision: http://reviews.llvm.org/D15439

llvm-svn: 263590
2016-03-15 21:33:10 +00:00
Pete Cooper e8d9df4ea5 Use __nl_symbol_ptr instead of __got in the stubs pass on x86 archs.
The non lazy atoms generated in the stubs pass use an image cache to
hold all of the pointers.  On arm archs, this is the __got section,
but on x86 archs it should be __nl_symbol_ptr.

rdar://problem/24572729

llvm-svn: 260271
2016-02-09 20:11:17 +00:00
Pete Cooper 35c3318edc Aligned __stub_helper section to 4-bytes.
ld64 aligns most of the stub's to 2 byte alignment, expect for
the stub helper common atoms which are 4 byte aligned.

This adds a new field to StubInfo which tracks this alignment
and ensures that this is the alignment we get in the final image.

rdar://problem/24570220

llvm-svn: 260248
2016-02-09 18:56:37 +00:00
Pete Cooper 1a6098b86b Add pointerKind() method to the MachO ArchHandler's. NFC.
The ObjCPass is going to need to create pointer sized relocations in
the ObjC sections.  This method will be used to give us a target independent
way of getting the correct kind for the refererence.

llvm-svn: 259441
2016-02-02 00:02:50 +00:00
Pete Cooper f91b22ce2c Move SimpleDefinedAtom::addReference to DefinedAtom.
Most of the other methods to access Reference's were on DefinedAtom so
this just keeps them all together.

This will be used in a future patch in ObjCPass which needs to add
new references.  The method is virtual because we may add references to
different data structures depending on whether we parsed a macho file or
yaml.

llvm-svn: 259436
2016-02-01 23:42:10 +00:00
Rui Ueyama 9071e4a6fa Fix Clang-tidy misc-use-override warnings, other minor fixes.
Patch from Eugene Zelenko!

llvm-svn: 247323
2015-09-10 18:51:36 +00:00
Rui Ueyama e75e50c045 Define make_dynamic_error_code(const char *).
The function took either StringRef or Twine. Since string literals are
ambiguous when resolving the overloading, many code calls used this
function with explicit type conversion. That led awkward code like
make_dynamic_error_code(Twine("Error occurred")).

This patch adds a function definition for string literals, so that
you can directly call the function with literals.

llvm-svn: 234841
2015-04-14 02:34:09 +00:00
Rui Ueyama f217ef0d75 Use alignment values everywhere instead of log2.
This patch defines implicit conversion between integers and PowerOf2
instances, so uses of the classes is now implicit and look like
regular integers. Now we are ready to remove the scaffolding.

llvm-svn: 233245
2015-03-26 02:03:44 +00:00
Shankar Easwaran a1d3637f3d [Core,MachO,Test] Remove trailing whitespace.
llvm-svn: 230192
2015-02-22 23:54:38 +00:00
Jean-Daniel Dupas c31da7010b [Mach-O] Rename enum typename for consistency. NFC
Typename shouldn't mix camel case and underscore.
Thanks to Rui for the remark.

llvm-svn: 229848
2015-02-19 12:38:54 +00:00
Jean-Daniel Dupas 9c222630e4 Update ARM and x86 ArchHandler to check switch completeness. NFC
Define an explicit type for arch specific reference kinds to make sure all cases are covered in switch statements.

llvm-svn: 229314
2015-02-15 15:23:48 +00:00
Jean-Daniel Dupas 1536f0641b Break some test. Revert until I got a proper fix
llvm-svn: 229249
2015-02-14 09:10:25 +00:00
Jean-Daniel Dupas 8860b8d70c Update ARM and x86 ArchHandler to match 64bits counterparts. NFC
Summary:
Define an explicit type for arch specific reference kind and use it in switch statement to make the compiler emit warnings if some case is not cover.
It will help to catch such errors when we add new mach-o reference kind.

Reviewers: shankarke, kledzik

Reviewed By: shankarke

Subscribers: shankarke, aemerson, llvm-commits

Projects: #lld

Differential Revision: http://reviews.llvm.org/D7612

llvm-svn: 229246
2015-02-14 08:34:37 +00:00
Chandler Carruth 89642a7b37 [cleanup] Re-sort #include lines using llvm/utils/sort_includes.py
This is just a mechanical cleanup, no functionality changed. This just
fixes very minor inconsistencies with how #include lines were spaced and
sorted in LLD.

llvm-svn: 225978
2015-01-14 11:26:52 +00:00
Nick Kledzik 2020efb9fe [mach-o] for 32-bit arm, in -r mode support B (not BL) to undefined symbol
When fixing up BL instructions, the linker has to compare the thumbness of the
target to decide if the instruction needs to be converted to BLX.  But with B
instruction there is no BX, so the linker asserts if the target is not the
same thumbness. This assert was firing in -r mode when the target was undefined
which it interpreted as being non-thumb.

Test case change is to add a B (in both thumb and arm code) to an undefined
symbol and round trip through -r mode.

llvm-svn: 222266
2014-11-18 22:08:50 +00:00
Simon Atanasyan 55c2699d29 Follow-up to r221913. Fix some -Wcast-qual warning reasons.
llvm-svn: 221974
2014-11-14 07:15:43 +00:00
Nick Kledzik f373c77f50 [mach-o] Fix lazy binding offsets
The way lazy binding works in mach-o is that the linker generates a helper
function and has the stub (PLT) initially jump to it.  The helper function
pushes an extra parameter then jumps into dyld.  The extra parameter is an
offset into the lazy binding info where dyld will find the information about
which symbol to bind and way lazy binding pointer to update.

llvm-svn: 221654
2014-11-11 01:31:18 +00:00
Tim Northover 40d3ad3319 TMP: fix readN & writeN to not encourage UB
llvm-svn: 220730
2014-10-27 22:48:35 +00:00
Nick Kledzik 9133f8c76d [mach-o] Support missing MH_SUBSECTIONS_VIA_SYMBOLS
All compiler generated mach-o object files are marked with MH_SUBSECTIONS_VIA_SYMBOLS.
But hand written assembly files need to opt-in if they are written correctly.
The flag means the linker can break up a sections at symbol addresses and
dead strip or re-order functions.

This change recognizes object files without the flag and marks its atoms as
not dead strippable and adds a layout-after chain of references so that the
atoms cannot be re-ordered.

llvm-svn: 220348
2014-10-21 23:45:37 +00:00
Shankar Easwaran 2b67fca033 Sort include files according to convention.
llvm-svn: 220131
2014-10-18 05:33:55 +00:00
Tim Northover 995abe34f9 [mach-o] avoid overly clever std::find_if
The bots were complaining (possibly because of a lack of traits on the iterator
I was trying to use). No functional change.

llvm-svn: 219843
2014-10-15 20:26:24 +00:00
Tim Northover 1cc4fb76da [mach-o] make __unwind_info defer to __eh_frame when necessary.
Not all situations are representable in the compressed __unwind_info format,
and when this happens the entry needs to point to the more general __eh_frame
description.

Just x86_64 implementation for now.

rdar://problem/18208653

llvm-svn: 219836
2014-10-15 19:32:21 +00:00
Tim Northover a6a6ab9949 [macho] Create references from __eh_frame FDEs to their function.
We'll also need references back to the CIE eventually, but for now making sure
we can work out what an FDE is referring to is enough.

The actual kind of reference needs to be different between architectures,
probably because of MachO's chronic shortage of relocation types but I don't
really want to know in case I find out something that distresses me even more.

rdar://problem/18208653

llvm-svn: 219824
2014-10-15 18:19:31 +00:00
Nick Kledzik 4121bce3f6 [mach-o] Add Pass to create are shim Atoms for ARM interworking.
Arm code has two instruction encodings "thumb" and "arm".  When branching from
one code encoding to another, you need to use an instruction that switches
the instruction mode.  Usually the transition only happens at call sites, and
the linker can transform a BL instruction in BLX (or vice versa).  But if the
compiler did a tail call optimization and a function ends with a branch (not
branch and link), there is no pc-rel BX instruction.

The ShimPass looks for pc-rel B instructions that will need to switch mode.
For those cases it synthesizes a shim which does the transition, then modifies
the original atom with the B instruction to target to the shim atom.

llvm-svn: 219655
2014-10-14 01:51:42 +00:00
Tim Northover cf78d37fd6 [mach-o] create __unwind_info section on x86_64
This is a minimally useful pass to construct the __unwind_info section in a
final object from the various __compact_unwind inputs. Currently it doesn't
produce any compressed pages, only works for x86_64 and will fail if any
function ends up without __compact_unwind.

rdar://problem/18208653

llvm-svn: 218703
2014-09-30 21:29:54 +00:00
Nick Kledzik 1bebb2832e [mach-o] Add support for arm64 (AAarch64)
Most of the changes are in the new file ArchHandler_arm64.cpp.  But a few
things had to be fixed to support 16KB pages (instead of 4KB) which iOS arm64
requires.  In addition the StubInfo struct had to be expanded because
arm64 uses two instruction (ADRP/LDR) to load a global which requires two
relocations.  The other mach-o arches just needed one relocation.

llvm-svn: 217469
2014-09-09 23:52:59 +00:00
Nick Kledzik 9b7b8ff32d [mach-o] Fix arm interworking with movw/movt
In some cases the address of a function will be materialized with a movw/movt
pair.  If the function is a thumb function, the low bit needs to be set on
the movw immediate value.

llvm-svn: 214277
2014-07-30 01:41:38 +00:00
Nick Kledzik 3fc5ffecf8 [mach-o] fix non-debug warnings
llvm-svn: 214145
2014-07-28 23:40:26 +00:00
Nick Kledzik 54fd4e5fcb [mach-o] Implement interworking between thumb and arm code
All iOS arm processor support switching between arm and thumb mode at call sites
by using the BLX instruction (instead of BL).  But the compiler does not know
the implementation mode for extern functions, so the linker must update BL/BLX
instructions to match what is linked is actually linked together.  In addition,
pointers to functions (such as vtables) must have the low bit set if the target
of the pointer is a thumb mode function.

llvm-svn: 214140
2014-07-28 23:06:09 +00:00
Nick Kledzik 21921375cc [mach-o] Add support for LC_DATA_IN_CODE
Sometimes compilers emit data into code sections (e.g. constant pools or
jump tables). These runs of data can throw off disassemblers.  The solution
in mach-o is that ranges of data-in-code are encoded into a table pointed to
by the LC_DATA_IN_CODE load command.

The way the data-in-code information is encoded into lld's Atom model is that
that start and end of each data run is marked with a Reference whose offset
is the start/end of the data run.  For arm, the switch back to code also marks
whether it is thumb or arm code.

llvm-svn: 213901
2014-07-24 23:06:56 +00:00
Nick Kledzik 7e9808f7de [mach-o] add initial support for modes in arm code.
This patch just supports marking ranges that are thumb code (vs arm code).
Future patches will mark data and jump table ranges. The ranges are encoded
as References with offsetInAtom being the start of the range and the target
being the same atom.

llvm-svn: 213712
2014-07-23 00:51:37 +00:00
Nick Kledzik b78ad899e5 [mach-o] add support for round tripping all arm/thumb relocations
Update the parse-arm-relocs.yaml test case to run the linker back to back
to ensure all relocations round trip in and out of mach-o.

llvm-svn: 213700
2014-07-22 23:07:49 +00:00
Nick Kledzik e1aaced0cb [mach-o] Add test case for armv6 (arm not thumb) hello world
llvm-svn: 213592
2014-07-22 00:49:49 +00:00
Nick Kledzik 2d432353ba [mach-o] implement more x86 and x86_64 relocation support
Add support for adding section relocations in -r mode.  Enhance the test
cases which validate the parsing of .o files to also round trip.  They now
write out the .o file and then parse that, verifying all relocations survived
the round trip.

llvm-svn: 213333
2014-07-17 23:16:21 +00:00
Nick Kledzik 2458bec7e7 [mach-o] refactor KindHandler into ArchHandler and simplify passes.
All architecture specific handling is now done in the appropriate
ArchHandler subclass.

The StubsPass and GOTPass have been simplified.  All architecture specific
variations in stubs are now encoded in a table which is vended by the
current ArchHandler.

llvm-svn: 213187
2014-07-16 19:49:02 +00:00