Commit Graph

365 Commits

Author SHA1 Message Date
Rafael Espindola
83ed6b7814 Use the ability to pwrite to simplify the ELF writer.
Now we don't have to do 2 synchronized passes to compute offsets and then
write the file.

This also includes a fix for the corner case of seeking in /dev/null. It
is not an error, but on some systems (Linux) the returned offset is
always 0. An error is signaled by returning -1. This is checked by
the existing tests now that "clang -o /dev/null ..." seeks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234952 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-14 22:54:16 +00:00
Rafael Espindola
c98092e28d Use raw_pwrite_stream in the object writer/streamer.
The ELF object writer will take advantage of that in the next commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234950 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-14 22:14:34 +00:00
Petar Jovanovic
01b026b023 Re-enable target-specific relocation table sorting and use it for Mips
Some targets (ie. Mips) have additional rules for ordering the relocation
table entries. Allow them to override generic sortRelocs(), which sorts
entries by Offset.
Then override this function for Mips, to emit HI16 and GOT16 relocations
against the local symbol in pair with the corresponding LO16 relocation.

Patch by Vladimir Stefanovic.

Differential Revision: http://reviews.llvm.org/D7414


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234883 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-14 13:23:34 +00:00
Alexander Kornienko
c16fc54851 Use 'override/final' instead of 'virtual' for overridden methods
The patch is generated using clang-tidy misc-use-override check.

This command was used:

  tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
    -checks='-*,misc-use-override' -header-filter='llvm|clang' \
    -j=32 -fix -format

http://reviews.llvm.org/D8925



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234679 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-11 02:11:45 +00:00
Rafael Espindola
4b72aeb95c Remove unused variable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234426 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-08 20:04:20 +00:00
Rafael Espindola
541279fdf9 Write the section header in the end.
One could make the argument for writing it immediately after the ELF header,
but writing it in the middle of the sections like we were doing just makes
it harder for no reason.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234400 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-08 11:41:24 +00:00
NAKAMURA Takumi
e93f977e8d ELFObjectWriter.cpp: Prune obsolete \param since r234342. [-Wdocumentation]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234377 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-08 00:38:50 +00:00
Rafael Espindola
13c7f90285 Delete commented code. Don't repeat name in comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234370 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-07 22:35:40 +00:00
Rafael Espindola
872266937b Don't subtract the header size just to add it back.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234362 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-07 21:51:41 +00:00
Rafael Espindola
8a781bee00 Remove intermediate variables.
The name of these variables was completely out of date with the information
stored in them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234345 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-07 19:17:47 +00:00
Rafael Espindola
c78f07ad00 Remove unused argument.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234342 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-07 19:00:17 +00:00
Rafael Espindola
9428f184be Be consistent when deciding if a relocation is needed.
Before when deciding if we needed a relocation in A-B, we wore only checking
if A was weak.

This fixes the asymmetry.

The "InSet" argument should probably be renamed to "ForValue", since InSet is
very MachO specific, but doing so in this patch would make it hard to read.

This fixes PR22815.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234165 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-06 15:27:57 +00:00
Rafael Espindola
83be4429b2 Store the sh_link of ARM_EXIDX directly in MCSectionELF.
This avoids some pretty horrible and broken name based section handling.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234142 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-06 04:25:18 +00:00
Rafael Espindola
6254dcc14b Simplify this function a bit. NFC.
The case values are not a tidy enum we can fully cover. They even ovelap
over the various extension.

Just use a default:

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234140 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-06 03:16:51 +00:00
Rafael Espindola
01183f6492 Simplify mapping from relocation sections to relocated sections.
Just store the section in MCSectionELF. This avoids multiple hash lookups.

This will also be used by ARM_EXIDX.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@234139 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-06 03:09:30 +00:00
Rafael Espindola
0bd11cd898 Special case the creation of relocation sections.
These sections are never looked up and we know when have to create them. Use
that to save adding them to the regular map and avoid a symbol->string->symbol
conversion for the group symbol.

This also makes the implementation independent of the details of how unique
sections are implemented.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233539 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-30 13:39:16 +00:00
Rafael Espindola
d033c4b576 Fix fixup evaluation when deciding what to relocate with.
The previous logic was to first try without relocations at all
and failing that stop on the first defined symbol.

That was inefficient and incorrect in the case part of the
expression could be simplified and another part could not
(see included test).

We now stop the evaluation when we get to a variable whose value
can change (i.e. is weak).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233187 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-25 13:16:53 +00:00
Rafael Espindola
4e86f54fdb Don't be over eager in evaluating a subtraction with a weak symbol.
In a subtraction of the form A - B, if B is weak, there is no way to represent
that on ELF since all relocations add the value of a symbol.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233139 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-24 23:48:44 +00:00
Yaron Keren
8b9cc2da07 Add missing ELFObjectWriter::reset() override, like other MC classes.
See detailed discussion at

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140915/235418.html

and r217907, r217948:

 http://llvm.org/viewvc/llvm-project?view=revision&revision=217907
 http://llvm.org/viewvc/llvm-project?view=revision&revision=217948



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232982 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-23 18:35:01 +00:00
David Blaikie
7610ba7d24 Fix uses of reserved identifiers starting with an underscore followed by an uppercase letter
This covers essentially all of llvm's headers and libs. One or two weird
cases I wasn't sure were worth/appropriate to fix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232394 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-16 18:06:57 +00:00
Daniel Sanders
547ba56bd0 Recommit r232027 with PR22883 fixed: Add infrastructure for support of multiple memory constraints.
The operand flag word for ISD::INLINEASM nodes now contains a 15-bit
memory constraint ID when the operand kind is Kind_Mem. This constraint
ID is a numeric equivalent to the constraint code string and is converted
with a target specific hook in TargetLowering.

This patch maps all memory constraints to InlineAsm::Constraint_m so there
is no functional change at this point. It just proves that using these
previously unused bits in the encoding of the flag word doesn't break
anything.

The next patch will make each target preserve the current mapping of
everything to Constraint_m for itself while changing the target independent
implementation of the hook to return Constraint_Unknown appropriately. Each
target will then be adapted in separate patches to use appropriate
Constraint_* values.

PR22883 was caused the matching operands copying the whole of the operand flags
for the matched operand. This included the constraint id which needed to be
replaced with the operand number. This has been fixed with a conversion
function. Following on from this, matching operands also used the operand
number as the constraint id. This has been fixed by looking up the matched
operand and taking it from there. 



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232165 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-13 12:45:09 +00:00
Benjamin Kramer
30fa873958 Make some non-constant static variables non-static or fully const.
Otherwise we have to emit thread-safe initialization for them. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230894 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-01 18:09:56 +00:00
NAKAMURA Takumi
c3f0baf8f1 Fix UTF8 chars to ASCII.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230479 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-25 11:02:00 +00:00
Rafael Espindola
e0a2541eb7 Add r228980 back.
Add support for having multiple sections with the same name and comdat.

Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229541 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 20:48:01 +00:00
Rafael Espindola
84f0507260 Add r228889 back.
Original message:
Invert the section relocation map.

It now points from rel section to section. Use it to set sh_info, avoiding
a brittle name lookup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229539 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 20:40:59 +00:00
Rafael Espindola
8fd9fc3297 Add r228888 back.
Original message:

Use the existing SymbolTableIndex instead of doing a lookup. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229538 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 20:37:50 +00:00
Rafael Espindola
07102899ac Add r228886 back now that r229530 fixed the issue lldb was hitting.
Original message:

Create the Seciton -> Rel Section map when it is first needed. NFC.

Saves a walk over every section.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229536 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-17 20:31:13 +00:00
Chandler Carruth
00ae03a747 Revert a series of commits starting at r228886 which is triggering some
regressions for LLDB on Linux. Rafael indicated on lldb-dev that we
should just go ahead and revert these but that he wasn't at a computer.
The patches backed out are as follows:

r228980: Add support for having multiple sections with the name and ...
r228889: Invert the section relocation map.
r228888: Use the existing SymbolTableIndex intsead of doing a lookup.
r228886: Create the Section -> Rel Section map when it is first needed.

These patches look pretty nice to me, so hoping its not too hard to get
them re-instated. =D

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229080 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-13 07:52:39 +00:00
Rafael Espindola
2fa06b171b Add support for having multiple sections with the same name and comdat.
Using this in combination with -ffunction-sections allows LLVM to output a .o
file with mulitple sections named .text. This saves space by avoiding long
unique names of the form .text.<C++ mangled name>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228980 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-12 23:29:51 +00:00
Rafael Espindola
9fbdbaa2d1 Invert the section relocation map.
It now points from rel section to section. Use it to set sh_info, avoiding
a brittle name lookup.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228889 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 23:38:33 +00:00
Rafael Espindola
723be8820c Use the existing SymbolTableIndex instead of doing a lookup. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228888 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 23:33:46 +00:00
Rafael Espindola
3ce0dd9867 Create the Seciton -> Rel Section map when it is first needed. NFC.
Saves a walk over every section.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228886 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 23:17:48 +00:00
Rafael Espindola
e3199deda2 Remove unused argument. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228884 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 23:11:18 +00:00
Rafael Espindola
98f9153ded Don't recompute the entire section map just to add 3 entries. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228881 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 22:41:26 +00:00
Rafael Espindola
f97b99e41c Remove unused argument. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228873 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 21:08:00 +00:00
Rafael Espindola
9936b80df5 Compute the ELF SectionKind from the flags.
Any code creating an MCSectionELF knows ELF and already provides the flags.

SectionKind is an abstraction used by common code that uses a plain
MCSection.

Use the flags to compute the SectionKind. This removes a lot of
guessing and boilerplate from the MCSectionELF construction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227476 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-29 17:33:21 +00:00
Rafael Espindola
06eb5aad37 [pr21886] Change MCJIT/ELF to support MSVC C++ mangled symbol.
The ELF format is used on Windows by the MCJIT engine. Thus, on Windows, the
ELFObjectWriter can encounter symbols mangled using the MS Visual Studio C++
name mangling. Symbols mangled using the MSVC C++ name mangling can legally
have "@@@" as a substring. The EFLObjectWriter should not interpret the "@@@"
substring as specifying GNU-style symbol versioning. The ELFObjectWriter
therefore check for the MSVC C++ name mangling prefix which is either "?", "@?",
"imp_?" or "imp_?@".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226830 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 14:20:45 +00:00
Rafael Espindola
a23cc6a1ea Add r224985 back with fixes.
The fixes are to note that AArch64 has additional restrictions on when local
relocations can be used. In particular, ld64 requires that relocations to
cstring/cfstrings use linker visible symbols.

Original message:

In an assembly expression like

bar:
  .long L0 + 1

the intended semantics is that bar will contain a pointer one byte past L0.

In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.

The solution used in ELF to use relocation with symbols if there is a non-zero
addend.

In MachO before this patch we would just keep all symbols in some sections.

This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.

This patch implements the non-zero addend logic for MachO too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226503 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 21:11:14 +00:00
Rafael Espindola
8327f0bca1 Revert "Add r224985 back with two fixes."
This reverts commit r225644 while I debug a regression.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226022 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 19:07:23 +00:00
Chandler Carruth
1b279144ec [cleanup] Re-sort all the #include lines in LLVM using
utils/sort_includes.py.

I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225974 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 11:23:27 +00:00
Rafael Espindola
5512415ade Add r224985 back with two fixes.
One is that AArch64 has additional restrictions on when local relocations can
be used. We have to take those into consideration when deciding to put a L
symbol in the symbol table or not.

The other is that ld64 requires the relocations to cstring to use linker
visible symbols on AArch64.

Thanks to Michael Zolotukhin for testing this!

Remove doesSectionRequireSymbols.

In an assembly expression like

bar:
.long L0 + 1

the intended semantics is that bar will contain a pointer one byte past L0.

In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.

The solution used in ELF to use relocation with symbols if there is a non-zero
addend.

In MachO before this patch we would just keep all symbols in some sections.

This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.

This patch implements the non-zero addend logic for MachO too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225644 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-12 18:13:07 +00:00
Lang Hames
bce877c84c Revert r225048: It broke ObjC on AArch64.
I've filed http://llvm.org/PR22100 to track this issue.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225228 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-06 00:54:32 +00:00
Rafael Espindola
8093abb745 Add r224985 back with a fix.
The issues was that AArch64 has additional restrictions on when local
relocations can be used. We have to take those into consideration when
deciding to put a L symbol in the symbol table or not.

Original message:

Remove doesSectionRequireSymbols.

In an assembly expression like

bar:
.long L0 + 1

the intended semantics is that bar will contain a pointer one byte past L0.

In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.

The solution used in ELF to use relocation with symbols if there is a non-zero
addend.

In MachO before this patch we would just keep all symbols in some sections.

This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.

This patch implements the non-zero addend logic for MachO too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225048 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-31 17:19:34 +00:00
Rafael Espindola
937e781f49 Revert "Remove doesSectionRequireSymbols."
This reverts commit r224985.

I am investigating why it made an Apple bot unhappy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225044 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-31 16:06:48 +00:00
Rafael Espindola
65300b95e6 Remove doesSectionRequireSymbols.
In an assembly expression like

bar:
.long L0 + 1

the intended semantics is that bar will contain a pointer one byte past L0.

In sections that are merged by content (strings, 4 byte constants, etc), a
single position in the section doesn't give the linker enough information.
For example, it would not be able to tell a relocation must point to the
end of a string, since that would look just like the start of the next.

The solution used in ELF to use relocation with symbols if there is a non-zero
addend.

In MachO before this patch we would just keep all symbols in some sections.

This would miss some cases (only cstrings on x86_64 were implemented) and was
inefficient since most relocations have an addend of 0 and can be represented
without the symbol.

This patch implements the non-zero addend logic for MachO too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224985 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-30 13:13:27 +00:00
Rafael Espindola
d8ee23f34c Add back commits r219835 and a fixed version of r219829.
The only difference from r219829 is using

getOrCreateSectionSymbol(*ELFSec)

instead of

GetOrCreateSymbol(ELFSec->getSectionName())

in ELFObjectWriter which causes us to use the correct section symbol even if
we have multiple sections with the same name.

Original messages:

r219829:
Correctly handle references to section symbols.

When processing assembly like

.long .text

we were creating a new undefined symbol .text. GAS on the other hand would
handle that as a reference to the .text section.

This patch implements that by creating the section symbols earlier so that
they are visible during asm parsing.

The patch also updates llvm-readobj to print the symbol number in the relocation
dump so that the test can differentiate between two sections with the same name.

r219835:
Allow forward references to section symbols.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220021 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-17 01:48:58 +00:00
Rafael Espindola
70a1be3f76 Revert commit r219835 and r219829.
Revert "Correctly handle references to section symbols."
Revert "Allow forward references to section symbols."

Rui found a regression I am debugging.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220010 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-17 01:06:02 +00:00
Rafael Espindola
ad04f5db82 Correctly handle references to section symbols.
When processing assembly like

.long .text

we were creating a new undefined symbol .text. GAS on the other hand would
handle that as a reference to the .text section.

This patch implements that by creating the section symbols earlier so that
they are visible during asm parsing.

The patch also updates llvm-readobj to print the symbol number in the relocation
dump so that the test can differentiate between two sections with the same name.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219829 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-15 18:55:30 +00:00
Rafael Espindola
90ce9f70e2 Simplify handling of --noexecstack by using getNonexecutableStackSection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219799 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-15 16:12:52 +00:00
Rafael Espindola
852c0d6372 Note that a gold bug has been fixed.
We should be able to stop working around it at some point in the future.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219115 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-06 12:33:27 +00:00