Commit Graph

15 Commits

Author SHA1 Message Date
Peter Collingbourne 66f1c9a858 Reland r330223, "COFF: Merge .idata, .didat and .edata into .rdata by default.", which was reverted in r330228.
In this reland I removed an unnecessary use of /debug in the test
delayimports32.test and used the /pdbaltpath flag in the test
pdb-publics-import.test, both of which avoid embedding absolute PDB
paths in executables which could affect later RVAs.

Original commit message:
> COFF: Merge .idata, .didat and .edata into .rdata by default.
>
> This saves a little space and matches what link.exe does.
>
> Tested using the chromium Windows trybots:
> https://chromium-review.googlesource.com/c/chromium/src/+/1014784

Differential Revision: https://reviews.llvm.org/D45737

llvm-svn: 330233
2018-04-17 23:28:52 +00:00
Peter Collingbourne 1254f3e77c Revert r330223, "COFF: Merge .idata, .didat and .edata into .rdata by default."
Seems to have uncovered some sort of non-determinism on the bots.

llvm-svn: 330228
2018-04-17 22:16:39 +00:00
Peter Collingbourne 09e0e2e656 COFF: Merge .idata, .didat and .edata into .rdata by default.
This saves a little space and matches what link.exe does.

Tested using the chromium Windows trybots:
https://chromium-review.googlesource.com/c/chromium/src/+/1014784

Differential Revision: https://reviews.llvm.org/D45737

llvm-svn: 330223
2018-04-17 21:44:31 +00:00
Hans Wennborg 9a9fc78744 COFF: Layout sections in the same order as link.exe
One place where this seems to matter is to make sure the .rsrc section comes
after .text. The Win32 UpdateResource() function can change the contents of
.rsrc. It will move the sections that come after, but if .text gets moved, the
entry point header will not get updated and the executable breaks. This was
found by a test in Chromium.

Differential Revision: https://reviews.llvm.org/D45260

llvm-svn: 329221
2018-04-04 19:15:55 +00:00
Jon Chesterfield e0ca2ff070 [LLD] Mark a number of x86 only tests to require x86
Noticed while testing for an out of tree target. There are probably more tests that should be so marked.
I'm not sure who owns these tests so I've added a few names I recognise from the recent history.

With advice from probinson, ruiu, rafael and dramatically improved by davidb. Thank you all!

Differential Revision: https://reviews.llvm.org/D34685

llvm-svn: 308335
2017-07-18 18:40:50 +00:00
Reid Kleckner c2eaccb0af Revert "Merge IAT and ILT."
This reverts r303374. It breaks Chrome's IAT patching code:
http://crbug.com/729077

llvm-svn: 304584
2017-06-02 18:49:38 +00:00
Rui Ueyama 9fbfd76fe3 Merge IAT and ILT.
Previously, LLD-produced executables had IAT (Import Address Table) and
ILT (Import Lookup Table) as separate chunks of data, although their
contents are identical. My interpretation of the COFF spec when I wrote
the COFF linker is that they need to be separate tables even though they
are the same.

But Peter found that the Windows loader is fine with executables in
which IAT and ILT are merged. This is a patch to merge IAT and ILT.
I confirmed that an lld-link self-hosted with this patch works fine.

Fixes https://bugs.llvm.org/show_bug.cgi?id=33064

Differential Revision: https://reviews.llvm.org/D33326

llvm-svn: 303374
2017-05-18 19:59:22 +00:00
Rui Ueyama 6872455c6d COFF: Make test commands shorter. NFC.
llvm-svn: 244227
2015-08-06 16:47:46 +00:00
Rui Ueyama 251b0e268b COFF: Remove the old COFF linker and make link an alias to link2.
It's time to remove old COFF linker because the new one is now complete.

llvm-svn: 244226
2015-08-06 16:19:35 +00:00
Rui Ueyama b0398827c2 COFF: Fix bug in garbage collector.
GC root may have non-regular defined symbols, such as DefinedImportThunk,
so this cast<> was a wrong assumption.

llvm-svn: 241382
2015-07-04 01:10:32 +00:00
Rui Ueyama 7383562bc9 COFF: Align DLL import thunks on 16-byte boundaries.
llvm-svn: 240806
2015-06-26 18:28:56 +00:00
Rui Ueyama fd99e01b91 COFF: Support import-by-ordinal DLL imports.
Symbols exported by DLLs can be imported not by name but by
small number or ordinal. Usually, symbols have both ordinals
and names, and in that case ordinals are called "hints" and
used by the loader as hints.

However, symbols can have only ordinals. They are called
import-by-ordinal symbols. You need to manage ordinals by hand
so that they will never change if you choose to use the feature.
But it's supposed to make dynamic linking faster because
it needs no string comparison. Not sure if that claim still
stands in year 2015, though. Anyways, the feature exists,
and this patch implements that.

llvm-svn: 238780
2015-06-01 21:05:27 +00:00
Rui Ueyama 3ee0fe4c2c COFF: Implement subsystem inference.
llvm-svn: 238668
2015-05-31 03:55:46 +00:00
Rui Ueyama c9bfe32010 COFF: Fill imort table HintName field.
Currently we set the field to zero, but as per the spec, we should
set numbers we read from import library files. The loader uses the
values as starting offsets for binary search when looking up imported
symbols from DLL.

llvm-svn: 238562
2015-05-29 15:45:35 +00:00
Rui Ueyama 411c636081 COFF: Add a new PE/COFF port.
This is an initial patch for a section-based COFF linker.

The patch has 2300 lines of code including comments and blank lines.
Before diving into details, you want to start from reading README
because it should give you an overview of the design.

All important things are written in the README file, so I write
summary here.

- The linker is already able to self-link on Windows.

- It's significantly faster than the existing implementation.
  The existing one takes 5 seconds to link LLD on my machine,
  while the new one only takes 1.2 seconds, even though the new
  one is not multi-threaded yet. (And a proof-of-concept multi-
  threaded version was able to link it in 0.5 seconds.)

- It uses much less memory (250MB vs. 2GB virtual memory space
  to self-host).

- IMHO the new code is much simpler and easier to read than
  the existing PE/COFF port.

http://reviews.llvm.org/D10036

llvm-svn: 238458
2015-05-28 19:09:30 +00:00