Previously we evaluated the values of LMA incorrectly for next cases:
.text : AT(ADDR(.text) - 0xffffffff80000000) { ... }
.data : AT(ADDR(.data) - 0xffffffff80000000) { ... }
.init.begin : AT(ADDR(.init.begin) - 0xffffffff80000000) { ... }
Reason was that we evaluated offset when VA was not assigned. For case above
we ended up with 3 loads that has similar LMA and it was incorrect.
That is critical for linux kernel.
Patch updates the offset after VA calculation. That fixes the issue.
Differential revision: https://reviews.llvm.org/D30163
llvm-svn: 295722
Previously LLD would error out just "ld.lld: error: unable to move location counter backward"
What does not really reveal the place of issue,
Patch adds location to the output.
Differential revision: https://reviews.llvm.org/D30187
llvm-svn: 295720
This case should be possible to handle, but it is hard:
* In order to create program headers correctly, we have to scan the
sections in the order they are in the file.
* To find that order, we have to "execute" the linker script.
* The linker script can contain SIZEOF_HEADERS.
So to support this we have to start with a guess of how many headers
we need (3), run the linker script and try to create the program
headers. If it turns out we need more headers, we run the script again
with a larger SIZEOF_HEADERS.
Also, running the linker script depends on knowing the size of the
sections, so we have to finalize them. But creating the program
headers can change the value stored in some sections, so we have to
split size finalization and content finalization.
Looks like the last part is also needed for range extension thunks, so
we might support this at some point. For now just report an error
instead of producing broken files.
llvm-svn: 295458
As specified here:
* https://sourceware.org/binutils/docs/ld/MEMORY.html#MEMORY
There are two deviations from what is specified for GNU ld:
1. Only integer constants and *not* constant expressions
are allowed in `LENGTH` and `ORIGIN` initializations.
2. The `I` and `L` attributes are *not* implemented.
With (1) there is currently no easy way to evaluate integer
only constant expressions. This can be enhanced in the
future.
With (2) it isn't clear how these flags map to the `SHF_*`
flags or if they even make sense for an ELF linker.
Differential Revision: https://reviews.llvm.org/D28911
llvm-svn: 292875
The feature is documented as
-----------------------------
The format of the dynamic list is the same as the version node
without scope and node name. See *note VERSION:: for more
information.
--------------------------------
And indeed qt uses a dynamic list with an 'extern "C++"' in it. With
this patch we support that
The change to gc-sections-shared makes us match bfd. Just because we
kept bar doesn't mean it has to be in the dynamic symbol table.
The changes to invalid-dynamic-list.test and reproduce.s are because
of the new parser.
The changes to version-script.s are the only case where we change
behavior with regards to bfd, but I would like to see a mix of
--version-script and --dynamic-list used in the wild before
complicating the code.
llvm-svn: 289082
Linker script doesn't create a section if it has no content. So the following
script doesn't create .norelocs section if it doesn't have any .rel* sections.
.norelocs : { *(.rel*) }
Later, if you assert that the size of .norelocs is 0, LLD printed out
an error message, because it didn't allow calling SIZEOF() on nonexistent
sections.
This patch allows SIZEOF() on nonexistent sections, so that you can do
something like this.
ASSERT(SIZEOF(.norelocs), "shouldn't contain .rel sections!")
Note that this behavior is compatible with GNU.
Differential Revision: https://reviews.llvm.org/D26810
llvm-svn: 287257
Propagate program headers by walking the commands, not the
sections. This allows us to propagate program headers even from
sections that don't end up in the output.
Fixes pr30997.
llvm-svn: 286837
The disadvantage is that we use uint64_t instad of uint32_t for some
value in 32 bit files. The advantage is a substantially simpler code,
faster builds and less code duplication.
llvm-svn: 286414
Previously, we do this piece of code to iterate over all input sections.
for (elf::ObjectFile<ELFT> *F : Symtab.getObjectFiles())
for (InputSectionBase<ELFT> *S : F->getSections())
It turned out that this mechanisms doesn't work well with synthetic
input sections because synthetic input sections don't belong to any
input file.
This patch defines a vector that contains all input sections including
synthetic ones.
llvm-svn: 286051
Previously, it didn't support the character class, so we couldn't
eliminate the use fo llvm::Regex. Now that it is supported, we
can remove compileGlobPattern, which converts a glob pattern to
a regex.
This patch contains optimization for exact/prefix/suffix matches.
Differential Revision: https://reviews.llvm.org/D26284
llvm-svn: 285949
This can speed up lld up to 5 times when linking applications
with large number of sections and using linker script.
Differential revision: https://reviews.llvm.org/D26241
llvm-svn: 285895
With this patch we keep track of the fact that . is a position in the
file and therefore not absolute. This allow us to compute relative
relocations that involve symbol that are defined in linker scripts
with '.'.
This fixes https://llvm.org/bugs/show_bug.cgi?id=30406
There is still more work to track absoluteness over the various
expressions, but this should unblock linking the EFI bootloader.
llvm-svn: 285641
We parse linker scripts very early, but whether an expression is
absolute or not can depend on a symbol defined in a .o. Given that, we
have to delay the computation of IsAbsolute. We can do that by storing
an AST when parsing or by also making IsAbsolute a function like we do
for the expression value. This patch implements the second option.
llvm-svn: 285628
And as a token of the new feature, make ALIGNOF always absolute.
This is a step in making it possible to have non absolute symbols out
of output sections.
llvm-svn: 285608
Previously, we have a lot of BumpPtrAllocators, but all these
allocators virtually have the same lifetime because they are
not freed until the linker finishes its job. This patch aggregates
them into a single allocator.
Differential revision: https://reviews.llvm.org/D26042
llvm-svn: 285452
If there is not sufficient address space, just give up and don't put
the header in the PT_LOAD.
This matches bfd behaviour and I found at least one script that
depends on having a section at address 0.
llvm-svn: 282750
The BYTE, SHORT, LONG, and QUAD commands store one, two, four, and eight bytes (respectively).
After storing the bytes, the location counter is incremented by the number of bytes
stored.
Previously our scripts handles these commands incorrectly. For example:
SECTIONS {
.foo : {
*(.foo.1)
BYTE(0x11)
...
We accepted the script above treating BYTE as input section description.
These commands are used in the wild though.
Differential revision: https://reviews.llvm.org/D24830
llvm-svn: 282429
DEFINED(symbol)
Return 1 if symbol is in the linker global symbol table and is defined before
the statement using DEFINED in the script, otherwise return 0.
Can be used to define default values for symbols. Found it in the wild.
Differential revision: https://reviews.llvm.org/D24858
llvm-svn: 282245
This is PR30442.
Previously we were failed to parce complex expressions like:
foo : { *(SORT_BY_NAME(bar) zed) }
Main idea of patch that globs and excludes can be wrapped in a SORT.
There is a difference in semanics of ld/gold:
ld likes:
*(SORT(EXCLUDE_FILE (*file1.o) .foo.1))
gold likes:
*(EXCLUDE_FILE (*file1.o) SORT(.foo.1))
Patch implements ld grammar, complex expressions like
next is not a problem anymore:
.abc : { *(SORT(.foo.* EXCLUDE_FILE (*file1.o) .bar.*) .bar.*) }
Differential revision: https://reviews.llvm.org/D24758
llvm-svn: 282078
This reverts commit r282021, bringing back r282015.
The problem was that the comparison function was not a strict weak
ordering anymore, which this patch fixes.
Original message:
Only restrict order if both sections are in the script.
This matches gold and bfd behavior and is required to handle some scripts.
The script has to assume where PT_LOADs start in order to align that
spot. If we don't allow section it doesn't know about to move to the
middle, we can need more PT_LOADs and those will not be aligned.
llvm-svn: 282035
With fix for 2 bots. Details about the fix performed is on a review page.
Initial commit message:
This is PR30387:
From PR description:
We fail to parse
SECTIONS
{
foo :
{
*(sec0 EXCLUDE_FILE (zed1.o) sec1 EXCLUDE_FILE (zed2.o) sec2 )
}
}
The semantics according to bfd are:
Include sec1 from every file but zed1.o
Include sec2 from every file but zed2.o
Include sec0 from every file
Patch implements the support.
Differential revision: https://reviews.llvm.org/D24650
llvm-svn: 281754
George Rimar