When -verbose is specified, patch outputs names of each input orphan section
assigned to output.
Differential revision: https://reviews.llvm.org/D37517
llvm-svn: 314098
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
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
Normally to find the offset of a value in a section, we have to
compute the value since the alignment is defined on the final address.
If the alignment is trivial, we can skip the value computation. This
allows us to know the offset even in cases where we cannot yet know
the value.
llvm-svn: 313777
We try to evaluate expressions early when possible, but it is not
possible to evaluate them early if they are based on a section.
Before we would get this wrong on ABSOLUTE expressions.
llvm-svn: 313764
Given a linker script that ends in
.some_sec { ...} ;
__stack_start = .;
. = . + 0x2000;
__stack_end = .;
lld would put orphan sections like .comment before __stack_end,
corrupting the intended meaning.
The reason we don't normally move orphans past assignments to . is to
avoid breaking
rx_sec : { *(rx_sec) }
. = ALIGN(0x1000);
/* The RW PT_LOAD starts here*/
but in this case, there is nothing after and it seems safer to put the
orphan section last. This seems to match bfd's behavior and is
convenient for writing linker scripts that care about the layout of
SHF_ALLOC sections, but not of any non SHF_ALLOC sections.
llvm-svn: 313646
When given
foobar = ALIGN(., 0x100);
my expectation from what the manual says is that the final address of
foobar will be aligned. It seems that bfd aligns the offset in the
section, which causes some odd results if the section is not 0x100
aligned. Gold aligns the address.
This changes lld to align the final address.
llvm-svn: 312979
'@' is a valid character in file paths, but the linker script tokenizer treats it
as a separate token. This was leading to an unexpected test failure, on our local
builds. This patch changes the test to quote the path to prevent this happening.
An alternative would have been to add '@' to the list of "unquoted tokens" in
ScriptLexer.cpp, but ld.bfd has the same behaviour as the current LLD.
Reviewers: ruiu
Differential Revision: https://reviews.llvm.org/D37689
llvm-svn: 312922
to separate commons based on file name patterns. The following linker script
construct does not work because commons are allocated before section placement
is done and the only synthesized BssSection that holds all commons has no file
associated with it:
SECTIONS { .common_0 : { *file0.o(COMMON) }}
This patch changes the allocation of commons to create a section per common
symbol and let the section logic do the layout.
Differential revision: https://reviews.llvm.org/D37489
llvm-svn: 312796
There is no need to check anything excepr that
symbol is not in output.
Previously additional iformation like symbol values
or flags were checked, that was not correct.
For example if we would provide symbol with different
value/visibility/type for case when should not provide
symbol at all, testcase would not fail.
llvm-svn: 312779
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
Previously LLD did not calculate LMAOffset correctly when
AT and MEMORY were used together.
Patch fixes PR34407.
Differential revision: https://reviews.llvm.org/D37469
llvm-svn: 312625
The problem with symbol assignments in implicit linker scripts is that
they can refer synthetic symbols such as _end, _etext or _edata. The
value of these symbols is currently fixed only after all linker script
commands are processed, so these assignments will be using non-final and
hence invalid value.
Rather than fixing the symbol values after all command processing have
finished, we instead change the logic to generate symbol assignment
commands that set the value of these symbols while processing the
commands, this ensures that the value is going to be correct by the time
any reference to these symbol is processed and is equivalent to defining
these symbols explicitly in linker script as BFD ld does.
Differential Revision: https://reviews.llvm.org/D36986
llvm-svn: 312305
linker script SECTION rules. This patch extends it to use a fully specified
file name as it appears in --trace output to match agains, i.e,
"<path>/<objname>.o" or "<path>/<libname>.a(<objname>.o)".
Differential Revision: https://reviews.llvm.org/D37031
llvm-svn: 311713
Currently, LLD checks whether there's enough space for headers by
checking if headers fit below the address of the first allocated
section. However, that's always thue if the binary doesn't start
at zero which means that LLD always emits a segment for headers,
even if no other sections belong to that segment.
This is a problem in cases when linker script is being used with a
non-zero start address when we don't want to make the headers visible
by not leaving enough space for them. This pattern is common in
embedded programming but doesn't work in LLD.
This patch changes the behavior of LLD in case when linker script
is being to match the behavior of BFD ld and gold, which is to only
place headers into a segment when they're covered by some output
section.
Differential Revision: https://reviews.llvm.org/D36256
llvm-svn: 311586
Previously up to 3 errors were reported at once,
with patch we always will report only one,
just like in other linker code.
Differential revision: https://reviews.llvm.org/D37015
llvm-svn: 311537
Previously we would crash on samples from testcase,
because were trying to access zero pointer to output section.
Differential revision: https://reviews.llvm.org/D36145
llvm-svn: 311311
We would previously crash on next script:
MEMORY { name : ORIGIN = .; }
Patch fixes that.
Differential revision: https://reviews.llvm.org/D36138
llvm-svn: 311073
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
This is PR33889,
Patch adds support of combination of linkerscript and
-symbol-ordering-file option.
If no sorting commands are present in script inside section declaration
and no --sort-section option specified, code uses sorting from ordering
file if any exist.
Differential revision: https://reviews.llvm.org/D35843
llvm-svn: 310045
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
Previously we would crash when tried to ALIGN(0).
Patch uses value 1 instead in this case, that
looks to be consistent with GNU linkers
and reasonable and simple behavior itself.
Differential revision: https://reviews.llvm.org/D35942
llvm-svn: 309372
This patch fixes a small issue with respect to how memory region names
are parsed on output section descriptions. For example, consider:
.text : { *(.text) } > rom
That can also be written like:
.text : { *(.text) } >rom
The latter form is accepted by GNU LD and is fairly common.
Differential Revision: https://reviews.llvm.org/D35920
llvm-svn: 309191
This is PR33714.
Previously for each input section offset of memory region
was incremented on a size of output section.
That resulted in a wrong error message saying about
overflow. Patch fixes that.
Differential revision: https://reviews.llvm.org/D35803
llvm-svn: 308955
Also add the test cases for the addition and subtraction both for
the relative and absolute case.
Differential Revision: https://reviews.llvm.org/D35346
llvm-svn: 308692
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
In filling the .got sections, InputSection::OutSecOff was added twice
when finding the position to apply a relocation: first time in
InputSection::writeTo() and then in SectionBase::getOffset().
Differential revision: https://reviews.llvm.org/D34232
llvm-svn: 308003
Patch removes restriction about moving location counter
backwards outside of output sections declarations.
That may be useful for some apps relying on such scripts,
known example is linux kernel.
Differential revision: https://reviews.llvm.org/D34977
llvm-svn: 307794
Script commands are processed before unused synthetic sections are
removed. Therefore, if a linker script matches one of these sections
it'll get emitted as an empty output section because the logic for
removing unused synthetic sections ignores script commands which
could have already matched and captured one of these sections. This
patch fixes that by also removing the unused synthetic sections from
the script commands.
Differential Revision: https://reviews.llvm.org/D34800
llvm-svn: 307037
This patch makes changes to allow sections without the SHF_ALLOC bit to be
assigned to segments in a linker script.
The assignment of output sections to segments is performed in
LinkerScript::createPhdrs. Previously, this function would bail as soon as it
encountered an output section which did not have the SHF_ALLOC bit set, thus
preventing any output section without SHF_ALLOC from being assigned to a
segment.
This restriction has now been removed from LinkerScript::createPhdrs and instead
a check for SHF_ALLOC has been added to LinkerScript::adjustSectionsAfterSorting
to not propagate program headers to sections without SHF_ALLOC which matches the
behaviour of bfd linker scripts.
Differential Revision: https://reviews.llvm.org/D34204
llvm-svn: 307013
It is somewhat pointless to check that a specific error is not
produced. That is already checked by the ld.lld exit value.
Instead make the test a bit stronger by checking that the output file
has the expected symbol and section.
llvm-svn: 306496
I found this while trying to build u-boot. It uses -Ttext in
combination with linker scripts.
My first reaction was to change the linker scripts to have the correct
value, but I found that it is actually quite convenient to have -Ttext
take precedence.
By having just
.text : { *(.text) }
In the script, they can define the text address in a single Makefile
and pass it to ld with -Ttext and for the C code with
-DFoo=value. Doing the same with linker scripts would require them to
be generated during the build.
llvm-svn: 305766
This patch adds support for segment NONE in linker scripts which enables the
specification that a section should not be assigned to any segment.
Note that GNU ld does not disallow the definition of a segment named NONE, which
if defined, effectively overrides the behaviour described above. This feature
has been copied.
Differential Revision: https://reviews.llvm.org/D34203
llvm-svn: 305700
This is necessary to ensure that sections containing symbols referenced
from linker scripts (e.g. in data commands) don't get GC'd.
Differential Revision: https://reviews.llvm.org/D34195
llvm-svn: 305452
Currently we do layout as if non alloc sections had an actual address
and then set it to zero. This produces a few odd results where a
symbol has an address that is inconsistent with the section address.
The simplest way to fix it is probably to just set the address earlier.
The behavior of bfd seems to be similar, but it only sets the non
alloc section address is missing from the linker script or if the
script has an explicit " : 0" setting the address of the output
section (which the default script does).
llvm-svn: 305323
This shows an oddity of this output. While the section address is 0,
the the symbol address is computed as if the section was allocatable.
llvm-svn: 305250
Previously, it couldn't parse
SECTIONS .text (0x1000) : { *(.text) }
because "(" was interpreted as the begining of the "(NOLOAD)" directive.
llvm-svn: 305006