Commit Graph

8555 Commits

Author SHA1 Message Date
Rafael Espindola 658a0c74ec Avoid using OutputSection::Sections. NFC.
We now used the InputSectionDescriptions in
OutputSectionCommand::finalize. This will allow moving
clearOutputSections earlier.

llvm-svn: 304827
2017-06-06 20:13:19 +00:00
Rafael Espindola 8c284acf14 Move finalize to OutputSectionCommands. NFC.
This removes a mapping from OutputSection to OutputSectionCommand and
is another step in moving clearOutputSections earlier.

llvm-svn: 304821
2017-06-06 19:40:01 +00:00
Rafael Espindola 13f412f6a2 Convert a use of OutputSections. NFC.
llvm-svn: 304820
2017-06-06 19:29:36 +00:00
Rafael Espindola 0e454a9837 Define __executable_start.
This is defined by both bfd and gold and used by the android libc.

llvm-svn: 304803
2017-06-06 16:18:48 +00:00
Peter Smith 8a2e00e631 [ELF] Refactor CreateThunks to extract the iteration through InputSections.
In preparation for inserting Thunks into InputSectionDescription::Sections
extract the loop that finds InputSections that may have calls that need
Thunks. This isn't much benefit now but this will be useful when we have to
extract the InputSectionDescriptions::Sections from the script.

Differential Revision: https://reviews.llvm.org/D33834

llvm-svn: 304783
2017-06-06 10:06:48 +00:00
Peter Smith 8f7565b6f2 [ELF] Refactor ThunkCreator to not key on OutputSection for Thunks
In preparation for inserting Thunks into InputSectionDescriptions this
simple change associates added Thunks with a vector of InputSections instead
of an OutputSection. As of now we are just using OutputSection::Sections.

Differential Revision: https://reviews.llvm.org/D33832

llvm-svn: 304782
2017-06-06 09:42:44 +00:00
George Rimar 1124001c68 [ELF] - Early return from writeTo() if section is SHT_NOBITS. NFCi.
That addresses port commit comments for https://reviews.llvm.org/D33646

llvm-svn: 304777
2017-06-06 07:46:28 +00:00
George Rimar 8cde9a7e77 [ELF] - Allow multiple comdats when producing relocatable output.
Previously LLD would fail for case when there are multiple comdats and -r.

That happened because it merged all ".group" (SHT_GROUP) sections into single
output, producing broken result. Such sections may have similar name, alignment and flags
and other properties. We need to produce separate output section for each such input one.

Differential revision: https://reviews.llvm.org/D33643

llvm-svn: 304769
2017-06-06 06:38:32 +00:00
Rafael Espindola a6fef0e5db Move clearOutputSections earlier.
This moves clearOutputSections and OutputSectionCommands creation as
early as possible without changing other code.

llvm-svn: 304751
2017-06-05 23:43:49 +00:00
Konstantin Zhuravlyov 4c882d90aa AMDGPU/LLD: Remove deprecated and unused elf definitions from tests
Differential Revision: https://reviews.llvm.org/D33691

llvm-svn: 304734
2017-06-05 20:57:17 +00:00
Petr Hosek 7953e62f2e [ELF] Define __dso_handle symbol if needed
Traditionally, it has been defined in crtbegin.o, which is typically
provided by libgcc or as part of the C library on some systems. However,
but there's no principled reason for it to be there. We optionaly
define this symbol, which can be used on platforms that don't provide
__dso_handle in crtbegin.o or which don't use crtbegin.o at all.

Differential Revision: https://reviews.llvm.org/D33856

llvm-svn: 304732
2017-06-05 20:42:34 +00:00
Dmitry Mikulin db3b87b2c0 Symbols re-defined with -wrap and -defsym need to be excluded from inter-
procedural optimizations to prevent dropping symbols and allow the linker
to process re-directs.

PR33145: --wrap doesn't work with lto.
Differential Revision: https://reviews.llvm.org/D33621

llvm-svn: 304719
2017-06-05 16:24:25 +00:00
George Rimar 60a0ea161e [ELF] - Make LLD remove gnu-lib compression prefix (".z") after decompression when using -r
This is PR33289.

Previously LLD leaved section naming as is and that lead to wrong result,
because we decompress sections when using -r,
and hence should remove ".z" prefix.

Differential revision: https://reviews.llvm.org/D33885

llvm-svn: 304711
2017-06-05 12:49:21 +00:00
Peter Smith 43e852fb79 [ELF] SHF_LINK_ORDER should sort based on InputSectionDescriptions
This change alters the sorting for OutputSections with the SHF_LINK_ORDER
flag in OutputSection::finalize() to use the InputSectionDescription
representation and not the OutputSection::Sections representation.

Differential revision: https://reviews.llvm.org/D33772

llvm-svn: 304700
2017-06-05 08:51:15 +00:00
Rafael Espindola c7c42f6ae0 Convert another OutputSections use.
This allows moving clearOutputSections a bit earlier.

llvm-svn: 304654
2017-06-03 06:51:22 +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
Reid Kleckner 146eb7a65f Re-land "COFF: migrate def parser from LLD to LLVM"
This reverts commit r304561 and re-lands r303490 & co.

The fix was to use "SymbolName" when translating LLD's internal export
list to lib/Object's short export struct. The SymbolName reflects the
actual symbol name, which may include fastcall and stdcall mangling bits
not included in the /EXPORT or .def file EXPORTS name:

@@ -434,8 +434,7 @@ std::vector<COFFShortExport> createCOFFShortExportFromConfig() {
   std::vector<COFFShortExport> Exports;
   for (Export &E1 : Config->Exports) {
     COFFShortExport E2;
-    E2.Name = E1.Name;
+    // Use SymbolName, which will have any stdcall or fastcall qualifiers.
+    E2.Name = E1.SymbolName;
     E2.ExtName = E1.ExtName;
     E2.Ordinal = E1.Ordinal;
     E2.Noname = E1.Noname;

llvm-svn: 304573
2017-06-02 17:53:06 +00:00
Reid Kleckner 5a1ed789e1 Add test case for LLD/COFF for stdcall exports in .def files
The .def file parser changes I reverted broke this test case, and
exported "__imp__foo" instead of "__imp__foo@8". This was
http://crbug.com/728726.

llvm-svn: 304572
2017-06-02 17:48:06 +00:00
Reid Kleckner d249e4a188 Revert "COFF: migrate def parser from LLD to LLVM"
This reverts commits r303490, r303491, r303493, and r303494.

This caused http://crbug.com/728726. Essentially, exporting stdcall
functions doesn't appear to work after this change. Reduced test case
soon.

llvm-svn: 304561
2017-06-02 16:26:24 +00:00
George Rimar 6a0644b24b [ELF] - Following commit for r304531 to fix BB.
Not sure why I did not faced that locally earlier, 
llvm-readobj did not have -s flag for 2/3 tests.

llvm-svn: 304539
2017-06-02 10:38:45 +00:00
George Rimar ef84219d21 [ELF] - Assign SHF_INFO_LINK flag to REL[A] sections.
Spec says: (http://www.sco.com/developers/gabi/latest/ch4.sheader.html)

sh_info
This member holds extra information, whose interpretation depends on the section type.
If the sh_flags field for this section header includes the attribute SHF_INFO_LINK, 
then this member represents a section header table index.

SHF_INFO_LINK
The sh_info field of this section header holds a section header table index.

Since sh_info for SHT_REL[A] sections should contain the section header index of the
section to which the relocation applies, this is
consistent with spec to put this flag. Behavior matches both bfd and gold as well.

Differential revision: https://reviews.llvm.org/D33763

llvm-svn: 304531
2017-06-02 09:17:45 +00:00
Rafael Espindola 0f7dc0e2d0 Run fabricateDefaultCommands before fixSectionAlignments.
This allows us to remove the PageAlign field. It will also allow
moving fabricateDefaultCommands earlier.

llvm-svn: 304513
2017-06-02 01:37:58 +00:00
Rafael Espindola bb7bd3eefe Simplify. NFC.
llvm-svn: 304511
2017-06-02 01:24:37 +00:00
Zachary Turner ebd3ae8371 [CodeView] Properly align symbol records on read/write.
Object files have symbol records not aligned to any particular
boundary (e.g. 1-byte aligned), while PDB files have symbol
records padded to 4-byte aligned boundaries.  Since they share
the same reading / writing code, we have to provide an option to
specify the alignment and propagate it up to the producer or
consumer who knows what the alignment is supposed to be for the
given container type.

Added a test for this by modifying the existing PDB -> YAML -> PDB
round-tripping code to round trip symbol records as well as types.

Differential Revision: https://reviews.llvm.org/D33785

llvm-svn: 304484
2017-06-01 21:52:41 +00:00
Rafael Espindola 6888072808 Move maybeCompress to OutputSectionCommand.
This removes a call to getCmd and allows us to move
clearOutputSections earlier.

llvm-svn: 304439
2017-06-01 16:57:48 +00:00
Rafael Espindola cca62ef861 Move synchronize earlier.
This is probably the correct location for it: next to
fabricateDefaultCommands. If we don't have a linker script, we
fabricate one. If we have one, we patch it.

llvm-svn: 304436
2017-06-01 16:42:16 +00:00
Rafael Espindola 3f235c71cc Move clearOutputSections earlier.
Now it is as early as it can go: just before synchronize. We now have
to move synchronize earlier too.

llvm-svn: 304434
2017-06-01 16:32:58 +00:00
Rafael Espindola 805f5152c5 Synchronize the linker script with -r.
I don't have a testcase in mind, but there is no reason to have the
linker script out of sync during a -r link.

llvm-svn: 304433
2017-06-01 16:30:12 +00:00
Rafael Espindola faf25a7216 Convert a few more uses of OutputSections. NFC.
Also needed to move clearOutputSections earlier.

llvm-svn: 304420
2017-06-01 16:26:28 +00:00
Rafael Espindola 8a0966ea03 Convert a few user of OutputSections NFC.
This is needed to move clearOutputSections earlier.

llvm-svn: 304419
2017-06-01 16:21:33 +00:00
George Rimar d602987271 [ELF] - Properly handle R_386_GOTPC relocation.
This is PR33243. R_GOTONLY_PC_FROM_END was not in a list of link time constant
expressions and that was a result of confusiing messages like PR shows:

/usr/bin/ld.lld: error: /usr/lib/go/src/runtime/alg.go:47: 
can't create dynamic relocation R_386_GOTPC against local symbol in readonly segment defined in /tmp/nice/go-link-597453838/go.o

Though in reality we just should not have try to create a dynamic relocation for this case at all.

Patch fixes the issue.

Differential revision: https://reviews.llvm.org/D33717

llvm-svn: 304393
2017-06-01 07:53:58 +00:00
George Rimar b940f65cd2 [ELF] - Do not crash when proccessing absolute symbols during GC.
This is PR33239, previously we segfault on given testcase.

Differential revision: https://reviews.llvm.org/D33713

llvm-svn: 304392
2017-06-01 07:47:56 +00:00
Rafael Espindola 05c4f67cf3 Move name lookup to script parsing time.
We were looking up sections by name during expression evaluation. By
keeping track of forward declarations we can do the lookup during
script parsing.

Doing the lookup earlier will be more efficient when assignAddresses
is run twice and removes two uses of OutputSections.

llvm-svn: 304381
2017-06-01 01:16:50 +00:00
Rafael Espindola 47c9f84d50 Simplify. NFC.
The sections are ordered, so we can just use the first one when
looking for the lowest address.

llvm-svn: 304369
2017-05-31 22:49:50 +00:00
Rafael Espindola cccd2c604e Merge two nested ifs. NFC.
llvm-svn: 304368
2017-05-31 22:46:19 +00:00
Rafael Espindola 969c6512c2 Move clearOutputSections earlier.
Another step into merging the linker script and non linker script code
paths.

llvm-svn: 304339
2017-05-31 20:22:27 +00:00
Rafael Espindola db5e56f7b2 Store a single Parent pointer for InputSectionBase.
Before InputSectionBase had an OutputSection pointer, but that was not
always valid. For example, if it was a merge section one actually had
to look at MergeSec->OutSec.

This was brittle and caused bugs like the one fixed by r304260.

We now have a single Parent pointer that points to an OutputSection
for InputSection, but to a SyntheticSection for merge sections and
.eh_frame. This makes it impossible to accidentally access an invalid
OutSec.

llvm-svn: 304338
2017-05-31 20:17:44 +00:00
Rafael Espindola d54c566510 Simplify. NFC.
llvm-svn: 304334
2017-05-31 19:53:40 +00:00
Rafael Espindola 0dc2510762 Simplify. NFC.
llvm-svn: 304330
2017-05-31 19:26:37 +00:00
Rafael Espindola 23db636080 Simplify. NFC.
llvm-svn: 304328
2017-05-31 19:22:01 +00:00
Rafael Espindola b47c6e5cbd Fix a crash.
We would crash if a SHF_LINK_ORDER section pointed to a non
InputSection section. Since those sections are not merged in order,
SHF_LINK_ORDER is pretty meaningless and we can error on that case.

llvm-svn: 304327
2017-05-31 19:09:52 +00:00
Peter Smith ea79b215d6 [ELF] .ARM.exidx sentinel section should use InputSectionDescriptions.
This change converts the writing of the .ARM.exidx sentinel section to use
the InputSectionDescriptions instead of OutputSection::Sections this is in
preparation for the retirement of OutputSection::Sections.
    
Differential Revision: https://reviews.llvm.org/D33500

llvm-svn: 304289
2017-05-31 09:02:21 +00:00
Rafael Espindola 180de970c8 Fix crash when processing relocations in .eh_frame.
This happens when attempting to link shared libraries using exceptions on
MIPS. It requires -z notext because clang generates R_MIPS_64 relocations
inside .eh_frame.
The crash happened because for EhInputSection the OutSec member is null.

Patch by Alexander Richardson!

llvm-svn: 304260
2017-05-31 00:23:23 +00:00
Rafael Espindola e39709b20d Check Live instead of the section type.
By the time we get here all live sections should have been combined
into InputSections.

llvm-svn: 304243
2017-05-30 20:40:03 +00:00
Rafael Espindola a85e8dda54 Remove unnecessary cast.
llvm-svn: 304240
2017-05-30 20:24:52 +00:00
Peter Smith 626c997aff [ELF] Add .ARM.exidx sentinel section to an OutputSectionDescription
When there is a linker script with .ARM.exidx in the SECTIONS
command we must add the .ARM.exidx sentinel section to the
InputSectionDescriptions as well as to OutputSection::Sections.

Differential Revision: https://reviews.llvm.org/D33496

llvm-svn: 304206
2017-05-30 11:51:02 +00:00
George Rimar fa71b2635c [ELF] - Fix comment. NFC.
llvm-svn: 304197
2017-05-30 07:51:25 +00:00
George Rimar d4096140e3 [ELF] - Do not crash when linkerscript applies fill to .bss.
I found that during visual inspection of code while wrote different patch.
Script in testcase probably have nothing common with real life, but
we segfault currently using it.

If output section is known NOBITS, there is no need to create
writers threads for doing nothing or proccess any filler logic that 
is useless here. We can just early return, that is what this patch do.

DIfferential revision: https://reviews.llvm.org/D33646

llvm-svn: 304192
2017-05-30 05:48:09 +00:00
Petr Hosek 08dfd53269 [ELF] Filter out non InputSection members from InputSections
InputSections may contain MergeInputSection members which trigger
a segmentation fault when trying to cast them to InputSection.

Differential Revision: https://reviews.llvm.org/D33628

llvm-svn: 304189
2017-05-30 05:17:58 +00:00
Petr Hosek 3c6de1a66c [ELF] Use late evaluation for ALIGN in expression
While the following expression is handled fine:

  PROVIDE_HIDDEN(newsym = oldsym + address);

The following expression triggers an error because the expression
is evaluated as absolute:

  PROVIDE_HIDDEN(newsym = ALIGN(oldsym, CONSTANT(MAXPAGESIZE)) + address);

To avoid this error, we use late evaluation for ALIGN by making the
alignment an attribute of the expression itself.

Differential Revision: https://reviews.llvm.org/D33629

llvm-svn: 304185
2017-05-30 03:18:28 +00:00