Commit Graph

161 Commits

Author SHA1 Message Date
David Majnemer
827bc7fe53 [MC, COFF] Unbreak support for COFF timestamps
Support for COFF timestamps was unintentionally broken in r246905 when
it was conditionally available depending on whether or not LLVM was
configured with LLVM_ENABLE_TIMESTAMPS.  However, Config/config.h was
never included which essentially broke the feature.  Due to lax testing,
the breakage was never identified until we observed strange failures
during incremental links of Chromium.

This issue is resolved by simply including Config/config.h in
WinCOFFObjectWriter and teaching lit that the MC/COFF/timestamp.s test
is conditionally supported depending on LLVM_ENABLE_TIMESTAMPS.  With
this in place, we can strengthen the test to ensure that it will not
accidentally get broken in the future.

This fixes PR25891.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256137 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-21 08:03:07 +00:00
Peter Collingbourne
41984d3288 MC: Simplify handling of temporary symbols in COFF writer.
The COFF object writer was previously adding unnecessary symbols to its
temporary data structures and cleaning them up later. This made the code
harder to understand and caused a bug (aliases classed as temporary symbols
would cause an assertion failure). A much simpler way of handling such
symbols is to ask the layout for their section-relative position when needed.

Tested with a bootstrap on Windows and by building Chrome.

Differential Revision: http://reviews.llvm.org/D14975

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254183 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-26 23:29:27 +00:00
Manuel Klimek
fc0981ecbc Fix bug where WinCOFFObjectWriter would assume starting from an empty output.
Starting on an input stream that is not at offset 0 would trigger the
assert in WinCOFFObjectWriter.cpp:1065:

  assert(getStream().tell() <= (*i)->Header.PointerToRawData &&
               "Section::PointerToRawData is insane!");

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253464 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-18 15:24:17 +00:00
Oliver Stannard
99ab11202f [Assembler] Make fatal assembler errors non-fatal
Currently, if the assembler encounters an error after parsing (such as an
out-of-range fixup), it reports this as a fatal error, and so stops after the
first error. However, for most of these there is an obvious way to recover
after emitting the error, such as emitting the fixup with a value of zero. This
means that we can report on all of the errors in a file, not just the first
one. MCContext::reportError records the fact that an error was encountered, so
we won't actually emit an object file with the incorrect contents.

Differential Revision: http://reviews.llvm.org/D14717



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253328 91177308-0d34-0410-b5e6-96231b3b80d8
2015-11-17 10:00:43 +00:00
Rafael Espindola
0eba49c22e Fix pr24486.
This extends the work done in r233995 so that now getFragment (in addition to
getSection) also works for variable symbols.

With that the existing logic to decide if a-b can be computed works even if
a or b are variables. Given that, the expression evaluation can avoid expanding
variables as aggressively and that in turn lets the relocation code see the
original variable.

In order for this to work with the asm streamer, there is now a dummy fragment
per section. It is used to assign a section to a symbol when no other fragment
exists.

This patch is a joint work by Maxim Ostapenko andy myself.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249303 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-05 12:07:05 +00:00
Reid Kleckner
cba458eecc Add assembler fatal error for undefined assembler labels in COFF writer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247814 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-16 16:26:29 +00:00
David Majnemer
6ad37ecd02 [MC] Generate a timestamp for COFF object files
The MS incremental linker seems to inspect the timestamp written into
the object file to determine whether or not it's contents need to be
considered.  Failing to set the timestamp to a date newer than the
executable will result in the object file not participating in
subsequent links.  To ameliorate this, write the current time into the
object file's TimeDateStamp field.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246607 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-01 23:46:11 +00:00
David Majnemer
3d58bd6369 [MC] Add support for generating COFF CRCs
COFF sections are accompanied with an auxiliary symbol which includes a
checksum.  This checksum used to be filled with just zero but this seems
to upset LINK.exe when it is processing a /INCREMENTAL link job.
Instead, fill the CheckSum field with the JamCRC of the section
contents.  This matches MSVC's behavior.

This fixes PR19666.

N.B.  A rather simple implementation of JamCRC is given.  It implements
a byte-wise calculation using the method given by Sarwate.  There are
implementations with higher throughput like slice-by-eight and making
use of PCLMULQDQ.  We can switch to one of those techniques if it turns
out to be a significant use of time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@246590 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-01 21:23:58 +00:00
Rafael Espindola
ea619d042f Revert "Centralize the information about which object format we are using."
This reverts commit r245047.

It was failing on the darwin bots. The problem was that when running

./bin/llc -march=msp430

llc gets to

  if (TheTriple.getTriple().empty())
    TheTriple.setTriple(sys::getDefaultTargetTriple());

Which means that we go with an arch of msp430 but a triple of
x86_64-apple-darwin14.4.0 which fails badly.

That code has to be updated to select a triple based on the value of
march, but that is not a trivial fix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245062 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-14 15:48:41 +00:00
Rafael Espindola
b0a171f7a0 Centralize the information about which object format we are using.
Other than some places that were handling unknown as ELF, this should
have no change. The test updates are because we were detecting
arm-coff or x86_64-win64-coff as ELF targets before.

It is not clear if the enum should live on the Triple. At least now it lives
in a single location and should be easier to move somewhere else.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245047 91177308-0d34-0410-b5e6-96231b3b80d8
2015-08-14 13:31:17 +00:00
David Majnemer
8a2d65cf4a [MC] Correctly escape .safeseh's symbol
This fixes PR24107.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242050 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-13 18:51:15 +00:00
Gabor Ballabas
4e0f6008b9 Reworking the test part of r241149
The test part of r241149 has been reverted in r241451, due to misplaced test cases.
This patch splits those test cases among the appropriate targets.

Differential Revision: http://reviews.llvm.org/D10897


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241283 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-02 16:53:23 +00:00
Andy Ayers
588f5f0cbb Revise test to run llc and llvm-mc separately.
Differential Revision: http://reviews.llvm.org/D10066

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238508 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-28 21:49:50 +00:00
Andy Ayers
edd2bb863e Don't omit the constant when computing a cross-section relative relocation.
Differential Revision: http://reviews.llvm.org/D9692

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237327 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-14 01:10:41 +00:00
Rafael Espindola
c59decb902 Add a proper fix for pr23025.
Instead of avoiding looking past every global symbol, only do so
if the symbol is in a comdat.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235181 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 11:27:13 +00:00
Rafael Espindola
e95f704ed9 Add a reduced testcase from pr23025.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235168 91177308-0d34-0410-b5e6-96231b3b80d8
2015-04-17 09:05:25 +00:00
David Blaikie
5a70dd1d82 [opaque pointer type] Add textual IR support for explicit type parameter to gep operator
Similar to gep (r230786) and load (r230794) changes.

Similar migration script can be used to update test cases, which
successfully migrated all of LLVM and Polly, but about 4 test cases
needed manually changes in Clang.

(this script will read the contents of stdin and massage it into stdout
- wrap it in the 'apply.sh' script shown in previous commits + xargs to
apply it over a large set of test cases)

import fileinput
import sys
import re

rep = re.compile(r"(getelementptr(?:\s+inbounds)?\s*\()((<\d*\s+x\s+)?([^@]*?)(|\s*addrspace\(\d+\))\s*\*(?(3)>)\s*)(?=$|%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|zeroinitializer|<|\[\[[a-zA-Z]|\{\{)", re.MULTILINE | re.DOTALL)

def conv(match):
  line = match.group(1)
  line += match.group(4)
  line += ", "
  line += match.group(2)
  return line

line = sys.stdin.read()
off = 0
for match in re.finditer(rep, line):
  sys.stdout.write(line[off:match.start()])
  sys.stdout.write(conv(match))
  off = match.end()
sys.stdout.write(line[off:])

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232184 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-13 18:20:45 +00:00
David Majnemer
ee711b5b16 X86: Form IMGREL relocations for LLVM Functions
We supported forming IMGREL relocations from ConstantExprs involving
__ImageBase if the minuend was a GlobalVariable.  Extend this
functionality to all GlobalObjects.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231456 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-06 08:11:32 +00:00
David Blaikie
7c9c6ed761 [opaque pointer type] Add textual IR support for explicit type parameter to load instruction
Essentially the same as the GEP change in r230786.

A similar migration script can be used to update test cases, though a few more
test case improvements/changes were required this time around: (r229269-r229278)

import fileinput
import sys
import re

pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)")

for line in sys.stdin:
  sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line))

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7649

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230794 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 21:17:42 +00:00
David Blaikie
198d8baafb [opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction
One of several parallel first steps to remove the target type of pointers,
replacing them with a single opaque pointer type.

This adds an explicit type parameter to the gep instruction so that when the
first parameter becomes an opaque pointer type, the type to gep through is
still available to the instructions.

* This doesn't modify gep operators, only instructions (operators will be
  handled separately)

* Textual IR changes only. Bitcode (including upgrade) and changing the
  in-memory representation will be in separate changes.

* geps of vectors are transformed as:
    getelementptr <4 x float*> %x, ...
  ->getelementptr float, <4 x float*> %x, ...
  Then, once the opaque pointer type is introduced, this will ultimately look
  like:
    getelementptr float, <4 x ptr> %x
  with the unambiguous interpretation that it is a vector of pointers to float.

* address spaces remain on the pointer, not the type:
    getelementptr float addrspace(1)* %x
  ->getelementptr float, float addrspace(1)* %x
  Then, eventually:
    getelementptr float, ptr addrspace(1) %x

Importantly, the massive amount of test case churn has been automated by
same crappy python code. I had to manually update a few test cases that
wouldn't fit the script's model (r228970,r229196,r229197,r229198). The
python script just massages stdin and writes the result to stdout, I
then wrapped that in a shell script to handle replacing files, then
using the usual find+xargs to migrate all the files.

update.py:
import fileinput
import sys
import re

ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")
normrep = re.compile(       r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))")

def conv(match, line):
  if not match:
    return line
  line = match.groups()[0]
  if len(match.groups()[5]) == 0:
    line += match.groups()[2]
  line += match.groups()[3]
  line += ", "
  line += match.groups()[1]
  line += "\n"
  return line

for line in sys.stdin:
  if line.find("getelementptr ") == line.find("getelementptr inbounds"):
    if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("):
      line = conv(re.match(ibrep, line), line)
  elif line.find("getelementptr ") != line.find("getelementptr ("):
    line = conv(re.match(normrep, line), line)
  sys.stdout.write(line)

apply.sh:
for name in "$@"
do
  python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name"
  rm -f "$name.tmp"
done

The actual commands:
From llvm/src:
find test/ -name *.ll | xargs ./apply.sh
From llvm/src/tools/clang:
find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}"
From llvm/src/tools/polly:
find test/ -name *.ll | xargs ./apply.sh

After that, check-all (with llvm, clang, clang-tools-extra, lld,
compiler-rt, and polly all checked out).

The extra 'rm' in the apply.sh script is due to a few files in clang's test
suite using interesting unicode stuff that my python script was throwing
exceptions on. None of those files needed to be migrated, so it seemed
sufficient to ignore those cases.

Reviewers: rafael, dexonsmith, grosser

Differential Revision: http://reviews.llvm.org/D7636

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230786 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 19:29:02 +00:00
Michael Kuperstein
012d5929f1 Fix quoting of #pragma comment for MS compat, LLVM part.
For #pragma comment(linker, ...) MSVC expects the comment string to be quoted, but for #pragma comment(lib, ...) the compiler itself quotes the library name.
Since this distinction disappears by the time the directive reaches the backend, move quoting for the "lib" version to the frontend.

Differential Revision: http://reviews.llvm.org/D7652

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229375 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-16 11:57:17 +00:00
David Majnemer
f50e261e1e MC, COFF: Align section contents to a four byte boundary
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228879 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 22:22:30 +00:00
David Majnemer
3c1b9d53d0 MC: Calculate intra-section symbol differences correctly for COFF
This fixes PR22060.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228565 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-09 06:31:31 +00:00
David Majnemer
fdac306a12 MC: Emit COFF section flags in the "proper" order
COFF section flags are not idempotent:
  'rd' will make a read-write section because 'd' implies write
  'dr' will make a read-only section because 'r' disables write

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228490 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-07 08:26:40 +00:00
Rafael Espindola
4b678bff4e Bring r226038 back.
No change in this commit, but clang was changed to also produce trivial comdats when
needed.

Original message:

Don't create new comdats in CodeGen.

This patch stops the implicit creation of comdats during codegen.

Clang now sets the comdat explicitly when it is required. With this patch clang and gcc
now produce the same result in pr19848.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226467 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-19 15:16:06 +00:00
Timur Iskhodzhanov
6a7c74de33 Revert r226242 - Revert Revert Don't create new comdats in CodeGen
This breaks AddressSanitizer (ninja check-asan) on Windows

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226251 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-16 08:38:45 +00:00
Rafael Espindola
dfe88a08c7 Revert "Revert Don't create new comdats in CodeGen"
This reverts commit r226173, adding r226038 back.

No change in this commit, but clang was changed to also produce trivial comdats for
costructors, destructors and vtables when needed.

Original message:

Don't create new comdats in CodeGen.

This patch stops the implicit creation of comdats during codegen.

Clang now sets the comdat explicitly when it is required. With this patch clang and gcc
now produce the same result in pr19848.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226242 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-16 02:22:55 +00:00
Timur Iskhodzhanov
d048b3be70 Revert Don't create new comdats in CodeGen
It breaks AddressSanitizer on Windows.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226173 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-15 16:14:34 +00:00
Rafael Espindola
33f5127540 Don't create new comdats in CodeGen.
This patch stops the implicit creation of comdats during codegen.

Clang now sets the comdat explicitly when it is required. With this patch clang and gcc
now produce the same result in pr19848.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226038 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 20:55:48 +00:00
Michael Kuperstein
08c26613e1 [COFF] Don't try to add quotes to already quoted linker directives
If a linker directive is already quoted, don't try to quote it again, otherwise it creates a mess.
This pops up in places like:
#pragma comment(linker,"\"/foo bar'\"")

Differential Revision: http://reviews.llvm.org/D6792

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224998 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-30 19:23:48 +00:00
Reid Kleckner
a834d6a4bb Fix Windows unwind info for functions in sections other than .text
Previously we assumed the section name had the form .text$foo, which is
what we used to do for inline functions. If the dollar wasn't present,
we'd put unwind data in the .pdata and .xdata sections for the main
.text section, which is incorrect.

Fixes PR22001.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224738 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-22 22:10:08 +00:00
Duncan P. N. Exon Smith
1ef70ff39b IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224257 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-15 19:07:53 +00:00
Duncan P. N. Exon Smith
8f616165e4 IR: Canonicalize metadata formatting, NFC
Canonicalize formatting of metadata to make it easier to upgrade via
scripts -- in particular, one line per metadata definition makes it more
`sed`-able.

This is preparation for changing the assembly syntax for metadata [1].

[1]: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20141208/248449.html

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224002 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-11 06:32:29 +00:00
David Majnemer
16d8031f94 MC, COFF: Use relocations for function references inside the section
Referencing one symbol from another in the same section does not
generally require a relocation.  However, the MS linker has a feature
called /INCREMENTAL which enables incremental links.  It achieves this
by creating thunks to the actual function and redirecting all
relocations to point to the thunk.

This breaks down with the old scheme if you have a function which
references, say, itself.  On x86_64, we would use %rip relative
addressing to reference the start of the function from out current
position.  This would lead to miscompiles because other references might
reference the thunk instead, breaking function pointer equality.

This fixes PR21520.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221678 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 08:43:57 +00:00
David Majnemer
3a1045d8db MC, COFF: Make bigobj test compatible with python3
No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219739 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-14 22:35:11 +00:00
David Majnemer
b315be205c MC: Rewrite bigobj test in python
This makes the test easier to work with.  No functionality change
intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219737 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-14 22:26:49 +00:00
David Majnemer
388c2d325a Add a test for writing COFF BigObj
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219729 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-14 21:47:53 +00:00
Timur Iskhodzhanov
0a5843e3b1 Fix COFF section index relocation should be 16 bits, not 32
Original patch by Andrey Guskov!
http://reviews.llvm.org/D5651



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219327 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 18:01:49 +00:00
David Majnemer
1fa70c99dc COFF: Don't oversize COMMON symbols when targeting BFD ld
COFF normally doesn't allow us to describe the alignment of COMMON
symbols.

It turns out that most linkers use the symbol size as a hint as to how
aligned the symbol should be.

However the BFD folks have added a .drectve command, which we
now support as of r219229, that allows us to specify the alignment
precisely.  With this in mind, stop rounding sizes up.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219281 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-08 06:38:53 +00:00
Saleem Abdulrasool
29890f73dc MC: add support for -aligncomm GNU extension
The GNU linker supports an -aligncomm directive that allows for power-of-2
alignment of common data.  Add support to emit this directive.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219229 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-07 19:37:57 +00:00
Hans Wennborg
4edcbaec90 WinCOFFObjectWriter: optimize the string table for common suffices
This is a follow-up from r207670 which did the same for ELF.

Differential Revision: http://reviews.llvm.org/D5530

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2014-09-29 22:43:20 +00:00
Reid Kleckner
dd8ce126d7 MC: Use @IMGREL instead of @IMGREL32, which we can't parse
Nico Rieck added support for this 32-bit COFF relocation some time ago
for Win64 stuff. It appears that as an oversight, the assembly output
used "foo"@IMGREL32 instead of "foo"@IMGREL, which is what we can parse.

Sadly, there were actually tests that took in IMGREL and put out
IMGREL32, and we didn't notice the inconsistency. Oh well. Now LLVM can
assemble it's own output with slightly more fidelity.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218437 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-25 02:09:18 +00:00
David Majnemer
d80fc698f3 MC: ReadOnlyWithRel section kinds should map to rdata in COFF
Don't consider ReadOnlyWithRel as a writable section in COFF, they
really belong in .rdata.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218268 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-22 20:39:23 +00:00
David Majnemer
31b080d57f MC: Support aligned COMMON symbols for COFF
link.exe:
Fuzz testing has shown that COMMON symbols with size > 32 will always
have an alignment of at least 32 and all symbols with size < 32 will
have an alignment of at least the largest power of 2 less than the size
of the symbol.

binutils:
The BFD linker essentially work like the link.exe behavior but with
alignment 4 instead of 32.  The BFD linker also supports an extension to
COFF which adds an -aligncomm argument to the .drectve section which
permits specifying a precise alignment for a variable but MC currently
doesn't support editing .drectve in this way.

With all of this in mind, we decide to play a little trick: we can
ensure that the alignment will be respected by bumping the size of the
global to it's alignment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218201 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-21 09:18:07 +00:00
David Majnemer
182c8ff6c0 Update tests which broke from r218189
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218191 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-20 21:18:43 +00:00
David Majnemer
1c1bde666c MC: Fix MCSectionCOFF::PrintSwitchToSection
We had a few bugs:
- We were considering the GVKind instead of just looking at the section
  characteristics
- We would never print out 'y' when a section was meant to be unreadable
- We would never print out 's' when a section was meant to be shared
- We translated IMAGE_SCN_MEM_DISCARDABLE to 'n' when it should've meant
  IMAGE_SCN_LNK_REMOVE

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218189 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-20 20:40:50 +00:00
David Majnemer
3f34ae97b9 MC: Treat ReadOnlyWithRel and ReadOnlyWithRelLocal as ReadOnly for COFF
A problem with our old behavior becomes observable under x86-64 COFF
when we need a read-only GV which has an initializer which is referenced
using a relocation: we would mark the section as writable.  Marking the
section as writable interferes with section merging.

This fixes PR21009.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218179 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-20 07:31:46 +00:00
David Majnemer
c7210b3f0b llvm-readobj: pretty-print special COFF section names
Print IMAGE_SYM_DEBUG and the like instead of (-2).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218172 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-20 00:25:06 +00:00
David Majnemer
b3a86a097b Object: Add support for bigobj
This adds support for reading the "bigobj" variant of COFF produced by
cl's /bigobj and mingw's -mbig-obj.

The most significant difference that bigobj brings is more than 2**16
sections to COFF.

bigobj brings a few interesting differences with it:
- It doesn't have a Characteristics field in the file header.
- It doesn't have a SizeOfOptionalHeader field in the file header (it's
  only used in executable files).
- Auxiliary symbol records have the same width as a symbol table entry.
  Since symbol table entries are bigger, so are auxiliary symbol
  records.

Write support will come soon.

Differential Revision: http://reviews.llvm.org/D5259

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2014-09-10 12:51:52 +00:00
Reid Kleckner
b9cb76d3f3 MC Win64: Put unwind info for COMDAT code into the same COMDAT group
Summary:
This fixes a long standing issue where we would emit many little .text
sections and only one .pdata and .xdata section. Now we generate one
.pdata / .xdata pair per .text section and associate them correctly.

Fixes PR19667.

Reviewers: majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D5181

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217176 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-04 17:42:03 +00:00