The ARM TLS relocations are placed on literal data and not the 
code-sequence, it is therefore not possible to implement the relaxTls* 
functions. This change updates handleMipsTlsRelocation() to
handleNoRelaxTlsRelocation() and incorporates ARM as well as Mips.

The ARM support in handleNoRelaxTlsRelocation() currently needs to ouput
the module index dynamic relocation in all cases as it is relying on the 
dynamic linker to set the module index in the got.

Should address PR30218

Differential Revision: https://reviews.llvm.org/D24827

llvm-svn: 282250

Previously we failed to parse next scripts because disallowed
a space between filler value and '=':

  .text : {
...
  } :text = 0x9090

Differential revision: https://reviews.llvm.org/D24831

llvm-svn: 282248

DEFINED(symbol)
Return 1 if symbol is in the linker global symbol table and is defined before
the statement using DEFINED in the script, otherwise return 0.

Can be used to define default values for symbols. Found it in the wild.

Differential revision: https://reviews.llvm.org/D24858

llvm-svn: 282245

If section contains local symbols ldd crashes, because local
symbols are added to symbol table before section is discarded
by linker script processor. This patch calls copyLocalSymbols()
after createSections, so discarded section symbols are not copied

llvm-svn: 282244

Found this operators used in the wild scripts, for example:

__got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >>2;
__fixup_entries = (. - _FIXUP_TABLE_)>>2;

Differential revision: https://reviews.llvm.org/D24860

llvm-svn: 282243

The ELF spec doesn't allow relocations to point directly to
a deduplicated COMDAT section but this unfortunately happens in
practice. Bail out early instead of crashing.

Differential Revision:  https://reviews.llvm.org/D24750

llvm-svn: 282197

This fixes a case where we would produce an unaligned PT_LOAD.

llvm-svn: 282180

With the recent changes there should always be a 1:1 correspondence in
the correct order between OutputSections and OutputSectionCommands.

llvm-svn: 282176

This also fixes the linker script accounting for the ELF header in
some places but not in others.

llvm-svn: 282173

It doesn't matter which direction we rotate and we haven't really
started optimizing the linker script code, so keep this simple.

llvm-svn: 282166

Before the symbols were becoming undefined.

llvm-svn: 282159

llvm-svn: 282149

llvm-svn: 282147

This should finally give a stable sorting over all implementations.

llvm-svn: 282118

The actual logic is to keep the output section if the output section
would have been ro/rw.

This is both simpler and more practical, as the intention is linker
scripts is to always keep of of a pair of ONLY_IF_RO/ONLY_IF_RW.

llvm-svn: 282099

This is PR30442.
Previously we were failed to parce complex expressions like:
foo : { *(SORT_BY_NAME(bar) zed) }

Main idea of patch that globs and excludes can be wrapped in a SORT.
There is a difference in semanics of ld/gold:
ld likes:
*(SORT(EXCLUDE_FILE (*file1.o) .foo.1))

gold likes:
*(EXCLUDE_FILE (*file1.o) SORT(.foo.1))

Patch implements ld grammar, complex expressions like 
next is not a problem anymore:
.abc : { *(SORT(.foo.* EXCLUDE_FILE (*file1.o) .bar.*) .bar.*) }


Differential revision: https://reviews.llvm.org/D24758

llvm-svn: 282078

When final image has several .bss sections, lld fails
because second .bss always has zero VA. This causes 
link error "Not enough space for ELF and program headers"

llvm-svn: 282067

It is not only a bit more straightforward now, but also next 2 issues are solved:

* It just crashed on ".foo : { *(EXCLUDE_FILE (*file1.o)) }" before.
* It accepted multiple EXCLUDE_FILEs in a row.

Differential revision: https://reviews.llvm.org/D24726

llvm-svn: 282060

This surfaced again with Rust. As per bug 30435, rustc creates a
mergeable section with a sh_entsize zero. It bit us before, too.
I think we should relax the input check rather than being too picky.

Differential Revision: https://reviews.llvm.org/D24789

llvm-svn: 282049

This reverts commit r282021, bringing back r282015.

The problem was that the comparison function was not a strict weak
ordering anymore, which this patch fixes.

Original message:

Only restrict order if both sections are in the script.

This matches gold and bfd behavior and is required to handle some scripts.

The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.

llvm-svn: 282035

This reverts commit r282015. It broke some bots.

llvm-svn: 282021

This matches gold and bfd behavior and is required to handle some scripts.

The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.

llvm-svn: 282015

Differential Revision: https://reviews.llvm.org/D24685

llvm-svn: 282006

This is particularly important when the symbol comes from a linker
script. It is common to use the same linker script for shared
libraries and executables. Without this we would always fail to link
shared libraries with -z,defs and a linker script with an ENTRY
directive.

llvm-svn: 281989

llvm-svn: 281984

Linker scripts are responsible for aliging '.'. Since they are
designed for bfd which has no --rosegment, they don't align the RO to
RX transition.

llvm-svn: 281978

We were already not creating them, and with this other parts of the
code don't have to worry about them.

llvm-svn: 281968

llvm-svn: 281951

InputSection<ELFT>::Discarded has no name and it's not backed by
a file. Trying to report it as discared will cause a nullptr
dereference, therefore a crash. Skip it.

Differential Revision:   https://reviews.llvm.org/D24731

llvm-svn: 281946

An input section named .data.rel.ro now maps to an output section
named .data.rel.ro. Before we were mapping it to .data.

llvm-svn: 281931

The InputSection variables in the Writer were named `C`. This
was because when the ELF linker was ported (from COFF)
the name `Chunks` for input sections was retained.
Luckily we switched to a more ELF-compliant jargon, but these
variables weren't reanamed accordingly during the transition.

llvm-svn: 281917

llvm-svn: 281901

Will Dietz found and reported that lld does not compile with gcc 6.2.0,
more details https://llvm.org/bugs/show_bug.cgi?id=30438

And confirmed this change fixes the issue.

llvm-svn: 281900

llvm-svn: 281836

llvm-svn: 281835

Our implementation supported integer value previously.
ld can use expression,
for example, it is OK to write
 . = SEGMENT_START("foobar", .);

Patch implements that.

llvm-svn: 281831

It was possible situation about some commands just were not processed
(were skipped) because of a bug appeared when constraint checking used.

Testcase is attached.

llvm-svn: 281818

llvm-svn: 281817

llvm-svn: 281805

It is important to give members names for readability.

llvm-svn: 281803