Differential revision: https://reviews.llvm.org/D26070

llvm-svn: 285680

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

llvm-svn: 285621

llvm-svn: 285611

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

No need to subtract then add Sec->getVA().

llvm-svn: 285580

llvm-svn: 285567

llvm-svn: 285489

llvm-svn: 285453

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: 285347

Now that it is easy to create input section and symbols, this is
simple.

llvm-svn: 285322

This fixes pr30803 by not relaxing that particular access. We could
also let adjustRelaxExpr know that the target is absolute so that it
uses R_RELAX_GOT_PC_NOPIC, but it is not clear if it is worth it.

llvm-svn: 285317

This allows us to set a value for it based on -m.

llvm-svn: 285294

Instead of having 3 section allocators per file, have 3 for all files.

This is a substantial performance improvement for some cases. Linking
chromium without gc speeds up by 1.065x.

This requires using _exit in fatal since we have to avoid destructing
an InputSection if fatal is called from the constructor.

Thanks to Rui for the suggestion.

llvm-svn: 285290

    
When static linking in ARM (like Mips) __tls_get_addr is defined by
the library so we should not define it as a synthetic.
    
We also need to add __exidx_start and __exidx_end for the .ARM.exidx
section as the static libc library startup code is expecting them to
be defined by the default linker script for static linking on ARM.

Differential revision: https://reviews.llvm.org/D25978

llvm-svn: 285279

Another step in making it easier to create symbols without an ELf_Sym.

llvm-svn: 285241

llvm-svn: 285240

All the global ones now just forward to the same constructor. This
makes it easier to construct them without creating a Elf_Sym.

llvm-svn: 285238

llvm-svn: 285236

llvm-svn: 285235

As the state of lld gets more complicated, shutting down gets more
expensive.

In a normal lld run we can just call _exit immediately after renaming
the temporary output file. We still want the ability to run a full
shutdown since that is useful for detecting memory leaks.

This patch adds a --full-shutdown flag and changes lit to use it.

llvm-svn: 285224

This allows a non template class to hold input sections.

llvm-svn: 285221

llvm-svn: 285220

llvm-svn: 285219

We used to have one allocator per file, which reduces the advantage of
using an allocator in the first place.

This is a small speed up is most cases. The largest speedup was in
1.014X in chromium no-gc. The largest slowdown was scylla at 1.003X.

llvm-svn: 285205

llvm-svn: 285190

This patch make lld show following details for undefined symbol errors:
- file (line)
- file (function name)
- file (section name + offset)

Differential revision: https://reviews.llvm.org/D25826

llvm-svn: 285186

llvm-svn: 285169

llvm-svn: 285164

This is in sync with what clang does.

llvm-svn: 285163

llvm-svn: 285149

Instead of storing a pointer, store the members we need.

The reason for doing this is that it makes it far easier to create
synthetic sections. It also avoids reading data from files multiple
times., which might help with cross endian linking and host
architectures with slow unaligned access.

There are obvious compacting opportunities, but this already has mixed
results even on native x86_64 linking.

There is also the possibility of better refactoring the code for
handling common symbols, but this already shows that a custom class is
not necessary.

llvm-svn: 285148

llvm-svn: 285082

We were fairly inconsistent as to what information should be accessed
with getSectionHdr and what information (like alignment) was stored
elsewhere.

Now all section info has a dedicated getter. The code is also a bit
more compact.

llvm-svn: 285079

llvm-svn: 285062

We were previously using the (static) addSynthetic function to create
*_start/*_end symbols. This function was doing almost the same thing as
addOptionalSynthetic, except that it would also create the symbol in the
case where it is unreferenced. Because the symbol has hidden visibility,
creating it in that case would have no effect other than adding another
entry to the static symbol table. Remove addSynthetic and change callers to
use addOptionalSynthetic instead.

Differential Revision: https://reviews.llvm.org/D25545

llvm-svn: 285021

llvm-svn: 284878

We were already using it in the larger sets/maps. This provides about
1% speedup in linking xul and chromium.

llvm-svn: 284862