On many architectures gcc and clang will recognize _GLOBAL_OFFSET_TABLE_ - .
and produce a relocation that can be processed without needing to know the
value of _GLOBAL_OFFSET_TABLE_. This is not always the case; for example ARM
gcc produces R_ARM_BASE_PREL but clang produces the more general
R_ARM_REL32 to _GLOBAL_OFFSET_TABLE_. To evaluate this relocation
correctly _GLOBAL_OFFSET_TABLE_ must be defined to be the either the base of
the GOT or end of the GOT dependent on architecture..

If/when llvm-mc is changed to recognize _GLOBAL_OFFSET_TABLE_ - . this
change will not be necessary for new objects. However there may still be
old objects and versions of clang.

Differential Revision: https://reviews.llvm.org/D34355

llvm-svn: 306282

llvm-svn: 306225

r306095 in LLVM has changed register positions for instruction aui.
This change updates the test that checks for aui.

llvm-svn: 306173

llvm-svn: 306135

llvm-svn: 306128

This is useful when an upper limit on the cache size needs to be
controlled independently of the amount of the amount of free space.

One use case is a machine with a large number of cache directories
(e.g. a buildbot slave hosting a large number of independent build
jobs). By imposing an upper size limit on each cache directory,
users can more easily estimate the server's capacity.

Differential Revision: https://reviews.llvm.org/D34547

llvm-svn: 306126

Summary:
For SECTION relocations against absolute symbols, MSVC emits the largest
output section index plus one. I've implemented that by threading a
global variable through DefinedAbsolute that is filled in by the Writer.
A more library-oriented approach would be to thread the Writer through
Chunk::writeTo and SectionChunk::applyRel*, but Rui seems to prefer
doing it this way.

MSVC rejects SECREL relocations against absolute symbols, but only when
the relocation is in a real output section. When the relocation is in a
CodeView debug info section destined for the PDB, it seems that this
relocation error is suppressed, and absolute symbols become zeros in the
object file. This is easily implemented by checking the input section
from which we're applying relocations.

This should fix errors about __safe_se_handler_table and
__guard_fids_table when linking the CRT and generating a PDB.

Reviewers: ruiu

Subscribers: aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D34541

llvm-svn: 306071

Now you run llvm-pdbutil dump <options>.  This is a followup
after having renamed the tool, whereas before raw was obviously
just the style of dumping, whereas now "dump" is the action to
perform with the "util".

llvm-svn: 306055

Previously, when symbol A is renamed B, both A and B end up having
the same name. This is because name is a symbol's attribute, and
we memcpy symbols for symbol renaming.

This pathc saves the original symbol name and restore it after memcpy
to keep the original name.

This patch shouldn't change program's meaning, but names in symbol
tables make more sense than before.

llvm-svn: 306036

Differential Revision: https://reviews.llvm.org/D34442

llvm-svn: 305983

This is unnecessary because --gc-sections runs before ICF.

Differential Revision: https://reviews.llvm.org/D34465

llvm-svn: 305954

Summary:
The main complexity in adding symbol records is that we need to
"relocate" all the type indices. Type indices do not have anything like
relocations, an opaque data structure describing where to find existing
type indices for fixups. The linker just has to "know" where the type
references are in the symbol records. I added an overload of
`discoverTypeIndices` that works on symbol records, and it seems to be
able to link the standard library.

Reviewers: zturner, ruiu

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D34432

llvm-svn: 305933

This works around a strange interaction with Authenticode signatures,
in which a signed PE executable with {Major,Minor}LinkerVersion = 0.0
fails to validate on Windows 7 (but is OK on Windows 10). Setting the
linker version to 14.0 (which is what VS2015 outputs) makes it work
again.

Patch by Simon Tatham <simon.tatham@arm.com>.

llvm-svn: 305929

The --exclude-libs option is not a popular option, but at least some
programs in Android depend on it, so it's worth to support it.

Differential Revision: https://reviews.llvm.org/D34422

llvm-svn: 305920

llvm-svn: 305877

VC2017 contains these new symbols as undefined symobls. They are used
for /guard:cf. Since we do not support the control flow guard, but we
want to at least ignore these symbols so that we can link against VS2017
libraries.

Fixes https://bugs.chromium.org/p/chromium/issues/detail?id=727193.

llvm-svn: 305876

llvm-svn: 305868

We forgot to serialize these because llvm-readobj didn't dump them. They
are typically all zeros in an object file. The linker fills them in with
relocations before adding them to the PDB. Now we can properly round
trip these symbols through pdb2yaml -> yaml2pdb.

I made these fields optional with a zero default so that we can elide
them from our test cases.

llvm-svn: 305857

The option numbers in the macro were off by one which
leads to some confusion.  There are actually 12 arguments
to this macro.

Differential Revision: https://reviews.llvm.org/D34413

llvm-svn: 305823

Summary:
Previously we didn't add debug info chunks to the SparseChunks array, so
they didn't participate in section GC. Now we do.

Reviewers: ruiu

Subscribers: aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D34356

llvm-svn: 305811

This is patch for GSoC project, bash-completion for clang.

To use this on bash, please run `source clang/utils/bash-autocomplete.sh`.
bash-autocomplete.sh is code for bash-completion.

In this patch, Options.td was mainly changed in order to add value class
in Options.inc.

llvm-svn: 305805

I found this while trying to build u-boot. It uses -Ttext in
combination with linker scripts.

My first reaction was to change the linker scripts to have the correct
value, but I found that it is actually quite convenient to have -Ttext
take precedence.

By having just

.text : { *(.text) }

In the script, they can define the text address in a single Makefile
and pass it to ld with -Ttext and for the C code with
-DFoo=value. Doing the same with linker scripts would require them to
be generated during the build.

llvm-svn: 305766

to fail due to change in llvm trunk r305744.

llvm-svn: 305747

Differential Revision: https://reviews.llvm.org/D34358

llvm-svn: 305742

Summary: Have writeCOFFWriter return Expected<unique_ptr> instead of requiring being passed an uninitialized unique_ptr.

Reviewers: zturner, ruiu

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D34307

llvm-svn: 305730

llvm-svn: 305726

llvm-svn: 305718

llvm-svn: 305716

llvm-svn: 305714

Summary:
This is a first step towards getting line info to show up in VS and
windbg. So far, only llvm-pdbutil can parse the PDBs that we produce.
cvdump doesn't like something about our file checksum tables. I'll have
to dig into that next.

This patch adds a new DebugSubsectionRecordBuilder which takes bytes
directly from some other producer, such as a linker, and sticks it into
the PDB. Line tables only need to be relocated. No data needs to be
rewritten.

File checksums and string tables, on the other hand, need to be re-done.

Reviewers: zturner, ruiu

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D34257

llvm-svn: 305713

This patch adds support for segment NONE in linker scripts which enables the
specification that a section should not be assigned to any segment.

Note that GNU ld does not disallow the definition of a segment named NONE, which
if defined, effectively overrides the behaviour described above. This feature
has been copied.

Differential Revision: https://reviews.llvm.org/D34203

llvm-svn: 305700

In r305364, Rui changed the mechanism that parses -z option values slightly.
This caused a bug, as demonstrated by this test, which now fails:

---
# REQUIRES: x86
# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
# RUN: ld.lld %t.o -o %t -z max-page-size

.global _start
_start:
  nop
---

Before, the link succeeded and set the max-page-size to the target default.

After we get the following two error messages:
"invalid max-page-size: "
"max-page-size: value isn't a power of 2"

The latter error is because an uninitialised variable ends up being passed back
to getMaxPageSize).

This change ensures we only get the first error.

Reviewers: ruiu

Differential Revision: https://reviews.llvm.org/D34234

llvm-svn: 305679

    
The get{ARM,AArch64}UndefinedRelativeWeakVA() functions should only be
called for PC-relative relocations. Complete the supported pc-relative
relocations in the switch statement and make the default case unreachable.

The R_ARM_TARGET relocation can be evaluated as R_ARM_REL32 but it is only
used in the context of exception tables, and is never output with respect
to a weak reference so it does not appear in the switch statement.
    
Differential Revision: https://reviews.llvm.org/D34138

llvm-svn: 305673

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34316

llvm-svn: 305631

We would crash before.

llvm-svn: 305615

We would crash instead before.

llvm-svn: 305614

We would crash instead before.

llvm-svn: 305613

This option is no longer needed.

Differential Revision: https://reviews.llvm.org/D34302

llvm-svn: 305610

llvm-svn: 305601

In this patch, I flip the switch in DriverUtils from using the external
cvtres.exe tool to using the Windows Resource library in llvm.

I also fixed a bug where .rsrc sections were marked as discardable
memory and therefore were placed in the wrong order in the final PE.

Furthermore, I modified WindowsResource to write the coff directly to a
memory buffer instead of to file, also had it use the machine types
already declared in COFF.h instead creating my own enum.

Finally, I flipped the switch to allow all unit tests that had
previously run only on windows due to a winres dependency to run
cross-platform.

Reviewers: zturner, ruiu

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D34265

llvm-svn: 305592