Since OutputSection is no longer a template, it doesn't make much
sense to tempalte its factory class.

llvm-svn: 296308

Now that all special sections are SyntheticSections, we only need one
OutputSection class.

llvm-svn: 296127

With the current design an InputSection is basically anything that
goes directly in a OutputSection. That includes plain input section
but also synthetic sections, so this should probably not be a
template.

llvm-svn: 295993

Thanks to Rui Ueyama for suggestion.

llvm-svn: 295943

Now that InputSectionBase is not a template there is no reason to have
the two.

llvm-svn: 295924

Removing this template is not a big win by itself, but opens the way
for removing more templates.

llvm-svn: 295923

* Added comment.
* Pass std::string copy instead using move semantic.

llvm-svn: 295817

Previously we evaluated the values of LMA incorrectly for next cases:

.text : AT(ADDR(.text) - 0xffffffff80000000) { ... }
.data : AT(ADDR(.data) - 0xffffffff80000000) { ... }
.init.begin : AT(ADDR(.init.begin) - 0xffffffff80000000) { ... }

Reason was that we evaluated offset when VA was not assigned. For case above
we ended up with 3 loads that has similar LMA and it was incorrect.
That is critical for linux kernel.

Patch updates the offset after VA calculation. That fixes the issue.

Differential revision: https://reviews.llvm.org/D30163

llvm-svn: 295722

Previously LLD would error out just "ld.lld: error: unable to move location counter backward"
What does not really reveal the place of issue,
Patch adds location to the output.

Differential revision: https://reviews.llvm.org/D30187

llvm-svn: 295720

This case should be possible to handle, but it is hard:

* In order to create program headers correctly, we have to scan the
  sections in the order they are in the file.

* To find that order, we have to "execute" the linker script.

* The linker script can contain SIZEOF_HEADERS.

So to support this we have to start with a guess of how many headers
we need (3), run the linker script and try to create the program
headers. If it turns out we need more headers, we run the script again
with a larger SIZEOF_HEADERS.

Also, running the linker script depends on knowing the size of the
sections, so we have to finalize them. But creating the program
headers can change the value stored in some sections, so we have to
split size finalization and content finalization.

Looks like the last part is also needed for range extension thunks, so
we might support this at some point. For now just report an error
instead of producing broken files.

llvm-svn: 295458

We were only checking when the assignment was inside a section.

llvm-svn: 295454

We can do this now that the linker script and the writer agree on
which sections should be combined.

llvm-svn: 295341

Negative flags are still bit flags, so I think "not flag" is a very good name.

llvm-svn: 293143

As specified here:

* https://sourceware.org/binutils/docs/ld/MEMORY.html#MEMORY

There are two deviations from what is specified for GNU ld:

  1. Only integer constants and *not* constant expressions
     are allowed in `LENGTH` and `ORIGIN` initializations.

  2. The `I` and `L` attributes are *not* implemented.

With (1) there is currently no easy way to evaluate integer
only constant expressions.  This can be enhanced in the
future.

With (2) it isn't clear how these flags map to the `SHF_*`
flags or if they even make sense for an ELF linker.

Differential Revision: https://reviews.llvm.org/D28911

llvm-svn: 292875

Differential revision: https://reviews.llvm.org/D27194

llvm-svn: 290339

llvm-svn: 290231

llvm-svn: 290115

The current implementation of the output section data store commands
can only handle integer literals, but it should really handle arbitrary
expressions [1].  This commit fixes that.

[1] https://sourceware.org/binutils/docs-2.27/ld/Output-Section-Data.html#Output-Section-Data

Differential Revision: https://reviews.llvm.org/D27561

llvm-svn: 289152

The feature is documented as
-----------------------------
The format of the dynamic list is the same as the version node
without scope and node name.  See *note VERSION:: for more
information.
--------------------------------

And indeed qt uses a dynamic list with an 'extern "C++"' in it. With
this patch we support that

The change to gc-sections-shared makes us match bfd. Just because we
kept bar doesn't mean it has to be in the dynamic symbol table.

The changes to invalid-dynamic-list.test and reproduce.s are because
of the new parser.

The changes to version-script.s are the only case where we change
behavior with regards to bfd, but I would like to see a mix of
--version-script and --dynamic-list used in the wild before
complicating the code.

llvm-svn: 289082

Differential revision: https://reviews.llvm.org/D27335

llvm-svn: 288678

Differential revision: https://reviews.llvm.org/D27108

llvm-svn: 288019

This patch rearranges code a bit to make it easy to explain.

llvm-svn: 287515

Filler expressions in linker script "=fillexp" are always handled
as 32-bit integers. Thus the new type is more natural.

llvm-svn: 287445

llvm-svn: 287324

Linker script doesn't create a section if it has no content. So the following
script doesn't create .norelocs section if it doesn't have any .rel* sections.

  .norelocs : { *(.rel*) }

Later, if you assert that the size of .norelocs is 0, LLD printed out
an error message, because it didn't allow calling SIZEOF() on nonexistent
sections.

This patch allows SIZEOF() on nonexistent sections, so that you can do
something like this.

  ASSERT(SIZEOF(.norelocs), "shouldn't contain .rel sections!")

Note that this behavior is compatible with GNU.

Differential Revision: https://reviews.llvm.org/D26810

llvm-svn: 287257

This allows making symbols containing ADDR(section) synthetic,
and defining synthetic symbols outside SECTIONS block.

Differential revision: https://reviews.llvm.org/D25441

llvm-svn: 287090

Propagate program headers by walking the commands, not the
sections. This allows us to propagate program headers even from
sections that don't end up in the output.

Fixes pr30997.

llvm-svn: 286837

llvm-svn: 286826

llvm-svn: 286824

The disadvantage is that we use uint64_t instad of uint32_t for some
value in 32 bit files. The advantage is a substantially simpler code,
faster builds and less code duplication.

llvm-svn: 286414

Previously, we do this piece of code to iterate over all input sections.

  for (elf::ObjectFile<ELFT> *F : Symtab.getObjectFiles())
    for (InputSectionBase<ELFT> *S : F->getSections())

It turned out that this mechanisms doesn't work well with synthetic
input sections because synthetic input sections don't belong to any
input file.

This patch defines a vector that contains all input sections including
synthetic ones.

llvm-svn: 286051

Differential revision: https://reviews.llvm.org/D26320

llvm-svn: 286030

Previously, it didn't support the character class, so we couldn't
eliminate the use fo llvm::Regex. Now that it is supported, we
can remove compileGlobPattern, which converts a glob pattern to
a regex.

This patch contains optimization for exact/prefix/suffix matches.

Differential Revision: https://reviews.llvm.org/D26284

llvm-svn: 285949

This can speed up lld up to 5 times when linking applications 
with large number of sections and using linker script.

Differential revision: https://reviews.llvm.org/D26241

llvm-svn: 285895

With this patch we keep track of the fact that . is a position in the
file and therefore not absolute. This allow us to compute relative
relocations that involve symbol that are defined in linker scripts
with '.'.

This fixes https://llvm.org/bugs/show_bug.cgi?id=30406

There is still more work to track absoluteness over the various
expressions, but this should unblock linking the EFI bootloader.

llvm-svn: 285641

We parse linker scripts very early, but whether an expression is
absolute or not can depend on a symbol defined in a .o. Given that, we
have to delay the computation of IsAbsolute. We can do that by storing
an AST when parsing or by also making IsAbsolute a function like we do
for the expression value. This patch implements the second option.

llvm-svn: 285628

And as a token of the new feature, make ALIGNOF always absolute.

This is a step in making it possible to have non absolute symbols out
of output sections.

llvm-svn: 285608

Previously, we have a lot of BumpPtrAllocators, but all these
allocators virtually have the same lifetime because they are
not freed until the linker finishes its job. This patch aggregates
them into a single allocator.

Differential revision: https://reviews.llvm.org/D26042

llvm-svn: 285452

llvm-svn: 284177

Differential revision: https://reviews.llvm.org/D24298

llvm-svn: 283429