llvm-svn: 287318

MergeOutputSection class was a bit hard to use because it provdes
a series of finalize functions that have to be called in a right way
at a right time. It also intereacted with MergeInputSection, and the
logic was somewhat entangled between the two classes.

This patch simplifies it by providing only one finalize function.
Now, all you have to do is to call MergeOutputSection::finalize
when you have added all sections to the output section. Then, it
internally merges strings and initliazes StringPiece objects.
I think this is much easier to understand.

This patch also adds comments.

llvm-svn: 287314

llvm-svn: 287297

llvm-svn: 287296

Since the output has a section table too, it is meaningful to compute
the sh_link. In a more practical note, the binutils' strip crashes if
sh_link is not set for SHT_ARM_EXIDX.

llvm-svn: 287280

Also add new comments with MIPS GOT description.

llvm-svn: 287264

I hit an internal linker script that was defining _DYNAMIC instead of
letting the linker do it. It turns out that both bfd and gold allow
that.

This is pretty easy to implement, just make the linker defined symbol
weak. This should have no impact in the case where there is no user
defined symbol: The visibility is hidden, which causes the output to
still be local.

llvm-svn: 287260

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

llvm-svn: 287254

llvm-svn: 287253

llvm-svn: 287252

LLD supports multi-threading, and it seems to be working well as
you can see in r287140. In short, LLD runs a few percent to 30%
faster with -threads and more than 50% faster if you are using
-build-id (your mileage may vary depending on your computer).

However, I don't think most users even don't know about that because
-threads is not a default option.

This patch enables it by default.

Discussion thread:
http://lists.llvm.org/pipermail/llvm-dev/2016-November/107160.html

llvm-svn: 287237

llvm-svn: 287234

llvm-svn: 287231

llvm-svn: 287225

llvm-svn: 287218

Differential revision: https://reviews.llvm.org/D26740

llvm-svn: 287216

This patch updates a couple places where add_dependencies was being explicitly called to add dependencies on intrinsics_gen to instead use the DEPENDS named parameter. This cleanup is needed for a patch I'm working on to add a dependency debugging mode to the build system.

llvm-svn: 287205

llvm-svn: 287202

llvm-svn: 287200

Because it is uint16_t in the ELF spec. Using size_t was confusing.

llvm-svn: 287198

llvm-svn: 287197

We used to create a vector contantaining all version definitions
with wildcards because doing that was efficient. All patterns were
compiled to a regexp and matched against symbol names. Because
a regexp can be converted to a DFA, matching against union of patterns
is as cheap as matching against one patter.

We are no longer converting them to regexp. Our own glob pattern
handler doesn't do such optimization. Therefore, creating a vector
no longer makes sense.

llvm-svn: 287196

llvm-svn: 287192

llvm-svn: 287191

MIPS GOT handling is very different from other targets so it is better
to keep the code in the separatre section class MipsGotSection. This
patch introduces the new section and moves all MIPS specific code from
GotSection to the new class. I did not rename fields and methods in the
MipsGotSection class to reduce the diff and plan to do that by the
separate commit.

Differential revision: https://reviews.llvm.org/D26733

llvm-svn: 287150

Also add a comment saying that check() returns a value.

llvm-svn: 287136

This change separates all versioned locals to be a separate list in config,
that was suggested by Rafael and simplifies the logic a bit.

Differential revision: https://reviews.llvm.org/D26754

llvm-svn: 287132

Turns out some systems do define it. Not producing an error in this
case matches gold and bfd.

llvm-svn: 287125

Previously we did not support them,
patch implements this functionality

Differential revision: https://reviews.llvm.org/D26604

llvm-svn: 287124

Forgot about that, I am sorry.

llvm-svn: 287123

Particulaty "cannot preempt symbol" message
is extended with locations now.

Differential revision: https://reviews.llvm.org/D26738

llvm-svn: 287120

Our build-id is a tree hash anyway, so I'll define this as a synonym
for sha1. GNU gold takes this parameter, so this is for compatibility
with that.

llvm-svn: 287119

Differential revision: https://reviews.llvm.org/D26669

llvm-svn: 287092

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

Patch improves message to show locations for
"can't create dynamic relocation" error.

Differential revision: https://reviews.llvm.org/D26548

llvm-svn: 287086

llvm-svn: 287082

llvm-svn: 287072

The code to handle symbol versions is getting tricky and hard to
understand, so it is probably time to simplify it. This patch does
the following.

 - Add `DemangledSyms` variable to SymbolTable so that we don't
   need to pass it around to findDemangled.
 - Define `initDemangledSyms` to initialize the variable lazily.
 - hasExternCpp is removed because we no longer have to initialize
   the map eagerly.
 - scanScriptVersion is split.
 - Comments are updated.

llvm-svn: 287002

In this file, `sym` was used for both SymbolBody and SymbolVersion
although the two are completely different.

llvm-svn: 286992