Commit Graph

109 Commits

Author SHA1 Message Date
George Rimar 0984cfa9ab [ELF] - Removed excessive lookup. NFC.
llvm-svn: 327272
2018-03-12 14:15:38 +00:00
George Rimar e3f198d58a [ELF] - Change consume()->expect() in INSERT AFTER parsing.
AFTER keyword is mandatory and consume() was 
used by mistake here. We accepted broken script before
this patch, testcase shows the issue.

llvm-svn: 327260
2018-03-12 12:34:43 +00:00
George Rimar 9e2c8a9db1 [ELF] - Support "INSERT AFTER" statement.
This implements INSERT AFTER in a following way:

During reading scripts it collects all insert statements.
After we done and read all files it inserts statements into script commands list.

With that:
* Rest of code does know nothing about INSERT.
* Approach is straightforward and have no visible limitations.
* It is also easy to support INSERT BEFORE (was seen in clang code once).
* Should work for PR35877 and similar cases.

Cons:
* It assumes we have "main" scripts that describes sections.

Differential revision: https://reviews.llvm.org/D43468

llvm-svn: 327003
2018-03-08 14:54:38 +00:00
Rui Ueyama 067617f9ba Remove redundant casts.
llvm-svn: 326753
2018-03-05 23:50:45 +00:00
George Rimar 7b91e2133e [ELF] - Report location for div/mod by zero.
"division by zero" or "modulo by zero" are not
very informative errors and even probably confusing
as does not let to know that error is coming from linker script.
Patch adds location reporting.

Differential revision: https://reviews.llvm.org/D43934

llvm-svn: 326686
2018-03-05 10:02:44 +00:00
George Rimar b068b03793 [ELF] - Don't crash on broken MEMORY declaration.
LLD crashes with broken scripts shown in testcase,
because fails to read memory regon name and accesses
MemoryRegions's element which is nullptr.
Patch fixes it.

Differential revision: https://reviews.llvm.org/D43866

llvm-svn: 326431
2018-03-01 12:36:01 +00:00
George Rimar c4df670dea [ELF] - Do not remove empty sections that use symbols in expressions.
This is PR36515.

Currenly if we have a script like .debug_info 0 : { *(.debug_info) },
we would not remove this section and keep it in the output.
That does not work, because it is common case for
debug sections to have a zero address expression.
Patch changes behavior so that we remove only sections
that do not use symbols in its expressions.

Differential revision: https://reviews.llvm.org/D43863

llvm-svn: 326430
2018-03-01 12:27:04 +00:00
Rui Ueyama 39ba31ff50 Add "%" operator to the linker script.
This patch improves compatibility with GNU linkers.

Differential Revision: https://reviews.llvm.org/D43883

llvm-svn: 326348
2018-02-28 18:38:13 +00:00
Rui Ueyama 1d20222a48 Inline a trivial function. NFC.
llvm-svn: 326347
2018-02-28 18:25:00 +00:00
George Rimar 97f4d158bd [ELF] - Fix comment. NFC.
Addresses forgotten comment for D43071.

llvm-svn: 325332
2018-02-16 10:46:50 +00:00
George Rimar 1c08e9f5ce [ELF] - Support COPY, INFO, OVERLAY output sections attributes.
This is PR36298.

(COPY), (INFO), (OVERLAY) all have the same effect:
section should be marked as non-allocatable.

(https://www.eecs.umich.edu/courses/eecs373/readings/Linker.pdf, 
3.6.8.1 Output Section Type)

Differential revision: https://reviews.llvm.org/D43071

llvm-svn: 325331
2018-02-16 10:42:58 +00:00
Rui Ueyama 17324d8b34 Relax the grammar of the version script.
In GNU linkers, the last semicolon is optional. We can't link libstdc++
with lld because of that difference.

Differential Revision: https://reviews.llvm.org/D42820

llvm-svn: 324036
2018-02-01 23:46:17 +00:00
Rafael Espindola 490f0a4da9 Remove MemRegionOffset. NFC.
We can just use a member variable in MemoryRegion.

llvm-svn: 323399
2018-01-25 02:18:00 +00:00
Rafael Espindola 5e9c77624c Handle parsing AT(ADDR(.foo-bar)).
The problem we had with it is that anything inside an AT is an
expression, so we failed to parse the section name because of the - in
it.

llvm-svn: 322801
2018-01-18 01:14:57 +00:00
Rui Ueyama fe148c88da Remove dead code.
parseInt assumed that it could take a negative number literal (e.g.
"-123"). However, such number is in reality already handled as a
unary operator '-' followed by a number literal, so the number
literal is always non-negative. Thus, this code is dead.

llvm-svn: 322453
2018-01-14 04:44:21 +00:00
George Rimar 5d01a8be96 [ELF] - Fix for ld.lld does not accept "AT" syntax for declaring LMA region
AT> lma_region expression allows to specify the memory region
for section load address.

Should fix PR35684.

Differential revision: https://reviews.llvm.org/D41397

llvm-svn: 322359
2018-01-12 09:07:35 +00:00
Rafael Espindola 63a4a98e4c Add a comment about subtracting two non abs symbols. NFC.
llvm-svn: 321458
2017-12-26 18:11:14 +00:00
Rui Ueyama c67d6b2da0 Simplify script lexer.
Differential Revision: https://reviews.llvm.org/D41577

llvm-svn: 321453
2017-12-26 10:13:10 +00:00
Rafael Espindola 9cbb6dd1fc Result of subtracting two symbols should be absolute.
When two linker script symbols are subtracted, the result should be absolute.

This is the behavior of binutils' ld.

Patch by Erick Reyes!

llvm-svn: 321390
2017-12-22 21:55:28 +00:00
Rui Ueyama 2017d52b54 Move Memory.{h,cpp} to Common.
Differential Revision: https://reviews.llvm.org/D40571

llvm-svn: 319221
2017-11-28 20:39:17 +00:00
Alexander Richardson 1de78471f5 [ELF] Fall back to search dirs for linker scripts specified with -T
Summary:
This matches the behaviour of ld.bfd:
https://sourceware.org/binutils/docs/ld/Options.html#Options

If scriptfile does not exist in the current directory, ld looks for it in
the directories specified by any preceding '-L' options. Multiple '-T'
options accumulate.

Reviewers: ruiu, grimar

Reviewed By: ruiu, grimar

Subscribers: emaste, llvm-commits

Differential Revision: https://reviews.llvm.org/D40129

llvm-svn: 318655
2017-11-20 15:43:20 +00:00
Petr Hosek 8c7e8cce99 [ELF] Support expressions with -defsym option
Fixes PR34948.

Differential Revision: https://reviews.llvm.org/D39511

llvm-svn: 317396
2017-11-04 02:03:58 +00:00
George Rimar 8c825db25e [ELF] - Linkerscript: fixed non-determinism when handling MEMORY.
When findMemoryRegion do search to find a region for output section it
iterates over MemoryRegions which is DenseMap and so does not
guarantee iteration in insertion order. As a result selected region depends
on its name and not on its definition position
Testcase shows the issue, patch fixes it. Behavior after applying the patch
seems consistent with bfd.

Differential revision: https://reviews.llvm.org/D39544

llvm-svn: 317307
2017-11-03 08:21:51 +00:00
Bob Haarman b8a59c8aa5 [lld] unified COFF and ELF error handling on new Common/ErrorHandler
Summary:
The COFF linker and the ELF linker have long had similar but separate
Error.h and Error.cpp files to implement error handling. This change
introduces new error handling code in Common/ErrorHandler.h, changes the
COFF and ELF linkers to use it, and removes the old, separate
implementations.

Reviewers: ruiu

Reviewed By: ruiu

Subscribers: smeenai, jyknight, emaste, sdardis, nemanjai, nhaehnle, mgorny, javed.absar, kbarton, fedor.sergeev, llvm-commits

Differential Revision: https://reviews.llvm.org/D39259

llvm-svn: 316624
2017-10-25 22:28:38 +00:00
George Rimar f22ec9ddf6 [ELF] - Linkerscript: fix issue with SUBALIGN.
This is PR34886.

SUBALIGN command currently triggers failture if result expression
is zero. Patch fixes the issue, treating zero as 1, what is consistent with
other places and ELF spec it seems.

Patch also adds "is power of 2" check for this and other expressions
returning alignment.

Differential revision: https://reviews.llvm.org/D38846

llvm-svn: 316580
2017-10-25 14:50:51 +00:00
Rui Ueyama 4092016b7b Return early if it fails to parse a hex string.
This patch doesn't change the behavior of the program because it
would eventually return None at end of the function. But it is
better to return None early if we know it will eventually happen.

llvm-svn: 315495
2017-10-11 19:30:39 +00:00
Rui Ueyama 722221f5a7 Swap parameters of getSymbolValue.
Usually, a function that does symbol lookup takes symbol name as
its first argument. Also, if a function takes a source location hint,
it is usually the last parameter. So the previous parameter order
was counter-intuitive.

llvm-svn: 315433
2017-10-11 04:34:34 +00:00
Rui Ueyama f0403c601a Rename BytesDataCommand -> ByteCommand.
llvm-svn: 315431
2017-10-11 04:22:09 +00:00
Rui Ueyama 6b394caaf1 Rename Commands -> SectionCommands.
"Commands" was ambiguous because in the linker script, everything is
a command. We used to handle only SECTIONS commands, and at the time,
it might make sense to call them the commands, but it is no longer
the case. We handle not only SECTIONS but also MEMORY, PHDRS, VERSION,
etc., and they are all commands.

llvm-svn: 315409
2017-10-11 01:50:56 +00:00
Rui Ueyama a323e2a722 Rename HasSections -> HasSectionsComand.
HasSections is true if there is at least one SECTIONS linker
script command, and it is not directly related to whether we have
section objects or not. So I think the new name is better.

llvm-svn: 315405
2017-10-11 01:34:51 +00:00
Rui Ueyama ac27de9dc7 Remove ScriptConfiguration class and move the members to LinkerScript class.
ScriptConfiguration was a class to contain parsed results of
linker scripts. LinkerScript is a class to interpret it.

That ditinction was needed because we haven't instantiated
LinkerScript early (because, IIRC, LinkerScript class was a
ELFT template function). So, when we parse linker scripts,
we couldn't directly store the result to a LinkerScript instance.

Now, that limitation is gone. We instantiate LinkerScript
at the very beginning of our main function. We can directly
store parse results to a LinkerScript instance.

llvm-svn: 315403
2017-10-11 01:19:33 +00:00
Rui Ueyama 4fbe351817 Remove a constructor from ExprValue. NFC.
I think three ctors are too many for this simple class.

llvm-svn: 315394
2017-10-11 00:06:27 +00:00
Rui Ueyama 0ae2c24c5d Use llvm::Optional instead of UINT_MAX to represent a null value.
llvm-svn: 315168
2017-10-08 03:45:49 +00:00
Rui Ueyama 617e2f98a0 Make ScriptParser::checkSection a non-member function.
This patch also make its return type to `void` because
it always returns a given value as-is.

llvm-svn: 315165
2017-10-08 02:27:02 +00:00
Rui Ueyama 9b18f50f79 Remove a trivial function.
llvm-svn: 315164
2017-10-08 02:06:03 +00:00
Rafael Espindola 23be5e8d70 Consider ForceAbsolute again in moveAbsRight.
This patch goes back to considering ForceAbsolute in moveAbsRight, but
only if the second argument is not already absolute.

With this we can handle "foo + ABSOLUTE(foo)" and "ABSOLUTE(foo) + foo".

llvm-svn: 313800
2017-09-20 19:24:57 +00:00
Rafael Espindola 01a409520b Consider only A.Sec in moveAbsRight.
The idea of this function is to simplify the implementation of binary
operators like add.

A value might be absolute because of an ABSOLUTE expression, but it
still depends on the value of a section and we might not be able to
evaluate it early. We should keep such values on the LHS, so that we
can delay the evaluation.

We can now handle both "1 + ABSOLUTE(foo)" and "ABSOLUTE(foo) + 1".

llvm-svn: 313794
2017-09-20 18:56:08 +00:00
Rafael Espindola a6acd23c53 Align addresses, not offsets.
This fixes two more cases where we were aligning the offset in a
section, instead of the final address.

llvm-svn: 312983
2017-09-12 00:06:00 +00:00
Rafael Espindola 8016bdfd93 Handle empty dynamic lists.
llvm-svn: 312820
2017-09-08 18:53:43 +00:00
Rafael Espindola d72d97b3be If --dynamic-list is given, only those symbols are preemptible.
This allows combining --dynamic-list and version scripts too. The
version script controls which symbols are visible, and
--dynamic-list controls which of those are preemptible.

Unlike previous versions, undefined symbols are still considered
preemptible, which was the issue breaking the cfi tests.

This fixes pr34053.

llvm-svn: 312806
2017-09-08 18:16:59 +00:00
George Rimar 5f37541c73 [ELF] - Linkerscript: implement REGION_ALIAS.
REGION_ALIAS(alias, region)

Alias names can be added to existing memory regions created with
the MEMORY command. Each name corresponds to at most one
memory region.

Differential revision: https://reviews.llvm.org/D37477

llvm-svn: 312777
2017-09-08 08:23:15 +00:00
Rafael Espindola 0ff545c018 Revert "Revert "Revert r311468: If --dynamic-list is given, only those symbols are preemptible""
This reverts commit r312757.

Evgenii Stepanov reports that it broke some tests.

llvm-svn: 312771
2017-09-08 01:09:52 +00:00
Rafael Espindola b7d0be5896 Revert "Revert r311468: If --dynamic-list is given, only those symbols are preemptible"
If --dynamic-list is given, only those symbols are preemptible.

This allows combining --dynamic-list and version scripts too. The
version script controls which symbols are visible, and --dynamic-list
controls which of those are preemptible.

This fixes pr34053.

llvm-svn: 312757
2017-09-07 23:19:09 +00:00
Rui Ueyama 0440be4a42 Detect linker script INCLUDE cycles.
Differential Revision: https://reviews.llvm.org/D37524

llvm-svn: 312656
2017-09-06 18:14:08 +00:00
Rui Ueyama fd06b02558 Add a comment.
llvm-svn: 312655
2017-09-06 18:09:06 +00:00
Rui Ueyama e158f7c329 Revert r311468: If --dynamic-list is given, only those symbols are preemptible
This reverts commit r311468 because it broke some CFI bots.

llvm-svn: 311497
2017-08-22 21:54:58 +00:00
Rui Ueyama 9cbbacb910 If --dynamic-list is given, only those symbols are preemptible
Patch by Rafael Espíndola.

This is PR34053.

The implementation is a bit of a hack, given the precise location where
IsPreemtible is set, it cannot be used from
SymbolTable::handleAnonymousVersion.

I could add another method to SymbolTable if you think that would be
better.

Differential Revision: https://reviews.llvm.org/D36499

llvm-svn: 311468
2017-08-22 16:31:47 +00:00
Hafiz Abid Qadeer 6f1d954ef4 [ELF, LinkerScript] Support ! operator in linker script.
Summary: This small patch adds the support for ! operator in linker scripts. 

Reviewers: ruiu, rafael

Reviewed By: ruiu

Subscribers: meadori, grimar, emaste, llvm-commits

Differential Revision: https://reviews.llvm.org/D36451

llvm-svn: 310607
2017-08-10 15:25:47 +00:00
George Rimar ce6080819c [ELF] - Remove ScriptLexer::Error field and check ErrorCount instead.
D35945 introduces change when there is useless to check Error flag
in few places, but ErrorCount must be checked instead.

But then we probably can just check ErrorCount always. That should simplify
things. Patch do that.

Differential revision: https://reviews.llvm.org/D36266

llvm-svn: 310046
2017-08-04 10:34:14 +00:00
George Rimar 5fb17128f7 [ELF] - Do not segfault if linkerscript tries to access Target too early.
Following possible scripts triggered accessing to Target when it was not yet
initialized (was nullptr).

MEMORY { name : ORIGIN = DATA_SEGMENT_RELRO_END; }
MEMORY { name : ORIGIN = CONSTANT(COMMONPAGESIZE); }

Patch errors out instead.

Differential revision: https://reviews.llvm.org/D36140

llvm-svn: 309953
2017-08-03 16:05:08 +00:00