In the recognise test convert some ST1 multiple structure to ST1 single
structure to test the isST1SingleOpcode() function.
Differential Revision: https://reviews.llvm.org/D46263
llvm-svn: 331752
Add two test cases to improve the code coverage of ThunkSection creation
when there are no existing ThunkSections in range. There are two test
cases, one where a new section can be created and another to trigger the
"InputSection too large for range extension thunk" error message. A recent
code coverage report showed that this section of code wasn't covered by a
test case.
Differential Revision: https://reviews.llvm.org/D46261
llvm-svn: 331751
Summary: This is not technically required, but glibc unwind-dw2-fde.c classify_object_over_fdes expects there is a CIE record length 0 as a terminator.
Reviewers: ruiu, espindola
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D46566
llvm-svn: 331708
Our promise is that as long as there's no fatal error (i.e. broken
file is given to the linker), our main function returns to the caller.
So we can't use exit() in the regular code path.
Differential Revision: https://reviews.llvm.org/D46442
llvm-svn: 331690
On PowerPC calls to functions through the plt must be done through a call stub
that is responsible for:
1) Saving the toc pointer to the stack.
2) Loading the target functions address from the plt into both r12 and the
count register.
3) Indirectly branching to the target function.
Previously we have been emitting these call stubs to the .plt section, however
the .plt section should be reserved for the lazy symbol resolution stubs. This
patch moves the call stubs to the text section by moving the implementation from
writePlt to the thunk framework.
Differential Revision: https://reviews.llvm.org/D46204
llvm-svn: 331607
Specifically add support for custom sections that contain
relocations, and for the two new relocation types needed
by DWARF sections.
See: https://reviews.llvm.org/D44184
Patch by Yury Delendik!
Differential Revision: https://reviews.llvm.org/D44184
llvm-svn: 331566
The current support for V1 ABI in LLD is incomplete.
This patch removes V1 ABI support and changes the default behavior to V2 ABI,
issuing an error when using the V1 ABI. It also updates the testcases to V2
and removes any V1 specific tests.
Differential Revision: https://reviews.llvm.org/D46316
llvm-svn: 331529
Android AOSP has started specifying -m aarch64_elf64_le_vec as supported
by gold and BFD. This is a simple change to add the emulation so that LLD
doesn't immediately error when used as a linker in an AOSP build.
Differential Revision: https://reviews.llvm.org/D46429
llvm-svn: 331521
Implement the following relocations for AArch64:
R_AARCH64_TLSLE_LDST8_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST16_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST32_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST64_TPREL_LO12_NC
R_AARCH64_TLSLE_LDST128_TPREL_LO12_NC
These are specified in ELF for the 64-bit Arm Architecture.
Fixes pr36727
Differential Revision: https://reviews.llvm.org/D46255
llvm-svn: 331511
Now only IMAGE_REL_ARM64_ABSOLUTE and IMAGE_REL_ARM64_TOKEN
are unhandled.
Also add range checks for the existing BRANCH26 relocation.
Differential Revision: https://reviews.llvm.org/D46354
llvm-svn: 331505
PPC64 V2 ABI describes two entry points to a function. The global entry point
sets up the TOC base pointer. When calling a local function, the call should
branch to the local entry point rather than the global entry point.
Section 3.4.1 describes using the 3 most significant bits of the st_other
field to find out how many instructions there are between the local and global
entry point. This patch adds the correct offset required to branch to the local
entry point of a function.
Differential Revision: https://reviews.llvm.org/D45729
llvm-svn: 331046
This is slightly simpler to read IMHO. Now if a symbol has a position
in the file, it is Defined.
The main motivation is that with this a SharedSymbol doesn't need a
section, which reduces the size of SymbolUnion.
With this the peak allocation when linking chromium goes from 568.1 to
564.2 MB.
llvm-svn: 330966
It returns a different Expr only in the case of creating a function
symbol pointing to its plt entry. We can just add a call to
addPltEntry to avoid that and return void.
With this patch further simplifications of how we handle copy
relocations are possible.
llvm-svn: 330960
Currently, LLD supports ASSERT as a separate command.
We support two forms now.
Assign expression-form: . = ASSERT(0x100)
(old GNU ld required it and some scripts in the wild are still using
something like . = ASSERT((_end - _text <= (512 * 1024 * 1024)), "kernel image bigger than KERNEL_IMAGE_SIZE");
Nowadays above is not a mandatory form and command-like form is commonly used:
ASSERT(<expr>, "text);
The return value of the ASSERT is Dot. That was implemented in D30171.
It looks like (2) is just a short version of (1) then.
GNU ld does *not* list ASSERT as a SECTIONS command:
https://sourceware.org/binutils/docs/ld/SECTIONS.html#SECTIONS
Given above we probably can change ASSERT to be an assignment to Dot.
That makes the rest of the code much simpler. Patch do that.
Differential revision: https://reviews.llvm.org/D45434
llvm-svn: 330814
The fix is to copy Used when replacing the symbol.
Original message:
Do not keep shared symbols created from garbage-collected eliminated DSOs.
If all references to a DSO happen to be weak, and if the DSO is
specified with --as-needed, the DSO is not added to DT_NEEDED.
If that happens, we also need to eliminate shared symbols created
from the DSO. Otherwise, they become dangling references that point
to non-exsitent DSO.
Fixes https://bugs.llvm.org/show_bug.cgi?id=36991
Differential Revision: https://reviews.llvm.org/D45536
llvm-svn: 330788
The PPC64 V2 ABI restores the toc base by loading from an offset of 24 from r1.
This patch fixes the offset and updates the testcases from V1 to V2. It also
issues an error when a nop is missing after a call to an external function.
Differential Revision: https://reviews.llvm.org/D45892
llvm-svn: 330600
This is what link.exe does and lets us avoid needing to worry about
merging output characteristics while adding input sections to output
sections.
With this change we can't process /merge in the same way as before
because sections with different output characteristics can still
be merged into one another. So this change moves the processing of
/merge to just before we assign addresses. In the case where there
are multiple output sections with the same name, link.exe only merges
the first section with the source name into the first section with
the target name, and we do the same.
At the same time I also implemented transitive merging (which means
that /merge:.c=.b /merge:.b=.a merges both .c and .b into .a).
This isn't quite enough though because link.exe has a special case for
.CRT in 32-bit mode: it processes sections whose output characteristics
are DATA | R | W as though the output characteristics were DATA | R
(so that they get merged into things like constructor lists in the
expected way). Chromium has a few such sections, and it turns out
that those sections were causing the problem that resulted in r318699
(merge .xdata into .rdata) being reverted: because of the previous
permission merging semantics, the .CRT sections were causing the entire
.rdata section to become writable, which caused the SEH runtime to
crash because it apparently requires .xdata to be read-only. This
change also implements the same special case.
This should unblock being able to merge .xdata into .rdata by default,
as well as .bss into .data, both of which will be done in followups.
Differential Revision: https://reviews.llvm.org/D45801
llvm-svn: 330479
Part of the DBI stream is a list of variable length structures
describing each module that contributes to the final executable.
One member of this structure is a section contribution entry that
describes the first section contribution in the output file for
the given module.
We have been leaving this structure unpopulated until now, so with
this patch it is now filled out correctly.
Differential Revision: https://reviews.llvm.org/D45832
llvm-svn: 330457
Enables cleaning up confusion between which name variables are mangled
and which are unmangled, and --print-gc-sections then excersises and
tests that.
Differential Revision: https://reviews.llvm.org/D44440
llvm-svn: 330449
Relocation addends can be negative so should be written as
signed LEBs. This bug meant that writing value between 64
and 128 would be incorrectly interpreted as negative by the
object file readers.
Differential Revision: https://reviews.llvm.org/D45825
llvm-svn: 330374
Summary:
DLLs and executables with no exception handlers need to be marked with
IMAGE_DLL_CHARACTERISTICS_NO_SEH, even if they have a load config.
Discovered here when building Chromium with LLD on Windows:
https://crbug.com/833951
Reviewers: ruiu, mstorsjo
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45778
llvm-svn: 330300
Summary:
This change does three things:
- Try to find the file and line number of an undefined symbol
reference by reading codeview debug info.
- Try to find the name of the function or global variable with the
undefined symbol reference by searching the object file's symbol
table.
- Prints the information in the same style as the ELF linker.
Differential Revision: https://reviews.llvm.org/D45467
llvm-svn: 330235
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
I needed to revert r330223 because we were embedding an absolute PDB
path in the .rdata section, which ended up being laid out before the
.idata section and affecting its RVAs. This flag will let us control
the embedded path.
Differential Revision: https://reviews.llvm.org/D45747
llvm-svn: 330232
The DBI stream contains a list of module descriptors. At the
beginning of each descriptor is a structure representing the first
section contribution in the output file for that module. LLD
currently doesn't fill out this structure at all, but link.exe
does. So as a precursor to emitting this data in LLD, we first
need a way to dump it so that it can be checked.
This patch adds support for the dumping, and verifies via a test
that LLD emits bogus information.
llvm-svn: 330208
This is causing large numbers of Chromium test executables to crash on
shutdown. The relevant symbol seems to be __cxa_finalize, which gets
removed from the dynamic symbol table for some of the support libraries.
llvm-svn: 330164
MIPS ABI requires creation of the MIPS_RLD_MAP dynamic tag for non-PIE
executables only and MIPS_RLD_MAP_REL tag for both PIE and non-PIE
executables. The patch skips definition of the MIPS_RLD_MAP for PIE
files and defines MIPS_RLD_MAP_REL.
The MIPS_RLD_MAP_REL tag stores the offset to the .rld_map section
relative to the address of the tag itself.
Differential Revision: https://reviews.llvm.org/D43347
llvm-svn: 329996
If all references to a DSO happen to be weak, and if the DSO is
specified with --as-needed, the DSO is not added to DT_NEEDED.
If that happens, we also need to eliminate shared symbols created
from the DSO. Otherwise, they become dangling references that point
to non-exsitent DSO.
Fixes https://bugs.llvm.org/show_bug.cgi?id=36991
Differential Revision: https://reviews.llvm.org/D45536
llvm-svn: 329960
Summary:
The content of custome sections no longer includes the
name itself.
See: https://reviews.llvm.org/D45579
Subscribers: jfb, dschuff, jgravelle-google, aheejin, sunfish, llvm-commits
Differential Revision: https://reviews.llvm.org/D45580
llvm-svn: 329948
Copy user-defined custom sections into the output, concatenating
sections with the same name.
Differential Revision: https://reviews.llvm.org/D45340
llvm-svn: 329717
I'm proposing a new command line flag, --warn-backrefs in this patch.
The flag and the feature proposed below don't exist in GNU linkers
nor the current lld.
--warn-backrefs is an option to detect reverse or cyclic dependencies
between static archives, and it can be used to keep your program
compatible with GNU linkers after you switch to lld. I'll explain the
feature and why you may find it useful below.
lld's symbol resolution semantics is more relaxed than traditional
Unix linkers. Therefore,
ld.lld foo.a bar.o
succeeds even if bar.o contains an undefined symbol that have to be
resolved by some object file in foo.a. Traditional Unix linkers
don't allow this kind of backward reference, as they visit each
file only once from left to right in the command line while
resolving all undefined symbol at the moment of visiting.
In the above case, since there's no undefined symbol when a linker
visits foo.a, no files are pulled out from foo.a, and because the
linker forgets about foo.a after visiting, it can't resolve
undefined symbols that could have been resolved otherwise.
That lld accepts more relaxed form means (besides it makes more
sense) that you can accidentally write a command line or a build
file that works only with lld, even if you have a plan to
distribute it to wider users who may be using GNU linkers. With
--check-library-dependency, you can detect a library order that
doesn't work with other Unix linkers.
The option is also useful to detect cyclic dependencies between
static archives. Again, lld accepts
ld.lld foo.a bar.a
even if foo.a and bar.a depend on each other. With --warn-backrefs
it is handled as an error.
Here is how the option works. We assign a group ID to each file. A
file with a smaller group ID can pull out object files from an
archive file with an equal or greater group ID. Otherwise, it is a
reverse dependency and an error.
A file outside --{start,end}-group gets a fresh ID when
instantiated. All files within the same --{start,end}-group get the
same group ID. E.g.
ld.lld A B --start-group C D --end-group E
A and B form group 0, C, D and their member object files form group
1, and E forms group 2. I think that you can see how this group
assignment rule simulates the traditional linker's semantics.
Differential Revision: https://reviews.llvm.org/D45195
llvm-svn: 329636
Currently LLD sets OutSecOff in addSection for input sections.
That is a fake offset (just a rude approximation to remember the order),
used for sorting SHF_LINK_ORDER sections
(see resolveShfLinkOrder, compareByFilePosition).
There are 2 problems with such approach:
1. We currently change and reuse Size field as a value assigned. Changing size is
not good because leads to bugs. Currently, SIZEOF(.bss) for empty .bss returns 2
because we add two empty synthetic sections and increase size twice by 1.
(See PR37011: https://bugs.llvm.org/show_bug.cgi?id=37011)
2. Such approach simply does not work when --symbol-ordering-file is involved,
because processing of the ordering file might break the initial section order.
This fixes PR37011.
Differential revision: https://reviews.llvm.org/D45368
llvm-svn: 329560
The intention of -gc-sections flag was to check
that discarded is not in the output. It should be
specified in the executable command line invocation
and also, the symbol must be global as local symbols
are anyways not printed.
Differential revision: https://reviews.llvm.org/D45159
llvm-svn: 329559
This is for PR36716 and
this enables emitting STT_FILE symbols.
Output size affect is minor:
lld binary size changes from 52,883,408 to 52,949,400
clang binary size changes from 83,136,456 to 83,219,600
Differential revision: https://reviews.llvm.org/D45261
llvm-svn: 329557
Some platforms interpret the pound sign as one character. Platforms that use
Python 2.x actually interpret it as two characters because in the Python 2.x
version of lit, the string used for the file name is a byte string and the pound
sign is two bytes.
Patch by Stella Stamenova!
llvm-svn: 329472
Currently there are a few odd things about the warning about symbols
that cannot be ordered. This patch fixes:
* When there is an undefined symbol that resolves to a shared file, we
were printing the location of the undefined reference.
* If there are multiple comdats, we were reporting them all.
llvm-svn: 329371
This is similar to r329219, but for the entire section. Like r329219 I
don't expect this to have any real impact, it is just more consistent
and simpler.
llvm-svn: 329367
Previously, "size" column is 9 characters long which is too long
at least for 32-bit (because at maximum it needs 8 columns). This
patch make it one column shorter than before. That's also a reasonable
default for 64-bit.
llvm-svn: 329317
Currently, LLD print symbol assignment commands to the map file,
but it does not do that for assignments that are outside of the section
descriptions. Such assignments can affect the layout though.
The patch implements the following:
* Teaches LLD to print symbol assignments outside of section declaration.
* Teaches LLD to print PROVIDE/HIDDEN/PROVIDE hidden commands.
In case when symbol is not provided, nothing will be printed.
Differential revision: https://reviews.llvm.org/D44894
llvm-svn: 329272
Currently, LLD prints VA, but not LMA in a map file.
It seems can be useful to print both to reveal layout
details and patch implements it.
Differential revision: https://reviews.llvm.org/D44899
llvm-svn: 329271
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
We were ignoring the addend if the piece was dead. I don't expect this
to make a difference in any real world situations, but it is simpler
anyway.
llvm-svn: 329219
Added checks to test that we do not produce
output where VA of sections overruns the address
space available.
Differential revision: https://reviews.llvm.org/D43820
llvm-svn: 329063
This fixes PR36927.
The issue is next. Imagine we have -Ttext 0x7c and code below.
.code16
.global _start
_start:
movb $_start+0x83,%ah
So we have R_386_8 relocation and _start at 0x7C.
Addend is 0x83 == 131. We will sign extend it to 0xffffffffffffff83.
Now, 0xffffffffffffff83 + 0x7c gives us 0xFFFFFFFFFFFFFFFF.
Techically 0x83 + 0x7c == 0xFF, we do not exceed 1 byte value, but
currently LLD errors out, because we use checkUInt<8>.
Let's try to use checkInt<8> now and the following code to see if it can help (no):
main.s:
.byte foo
input.s:
.globl foo
.hidden foo
foo = 0xff
Here, foo is 0xFF. And addend is 0x0. Final value is 0x00000000000000FF.
Again, it fits one byte well, but with checkInt<8>,
we would error out it, so we can't use it.
What we want to do is to check that the result fits 1 byte well.
Patch changes the check to checkIntUInt to fix the issue.
Differential revision: https://reviews.llvm.org/D45051
llvm-svn: 329061
Having 8/16 bits dynamic relocations is incorrect.
Both gold and bfd (built from latest sources) disallow
that too.
Differential revision: https://reviews.llvm.org/D45158
llvm-svn: 329059
The Plt relative relocations are R_PPC64_JMP_SLOT in the V2 abi, and we only
reserve 2 double words instead of 3 at the start of the array of PLT entries for
lazy linking.
Differential Revision: https://reviews.llvm.org/D44951
llvm-svn: 329006
Adds a simple test for accessing a local global variable in the ElfV2 abi.
Checks that the toc base used is the expected offset from the .TOC. symbol,
and that the offsets for the global are calculated relative to the toc base.
llvm-svn: 328982
It generally does not matter much where we place sections ordered
by --symbol-ordering-file relative to other sections. But if the
ordered sections are hot (which is the case already for some users
of --symbol-ordering-file, and is increasingly more likely to be
the case once profile-guided section layout lands) and the target
has limited-range branches, it is beneficial to place the ordered
sections in the middle of the output section in order to decrease
the likelihood that a range extension thunk will be required to call
a hot function from a cold function or vice versa.
That is what this patch does. After D44966 it reduces the size of
Chromium for Android's .text section by 60KB.
Differential Revision: https://reviews.llvm.org/D44969
llvm-svn: 328905
Now that we have the ability to create short thunks, it is beneficial
for thunk sections to be surrounded by ThunkSectionSpacing bytes
of code on both sides in order to increase the likelihood that the
distance from the thunk to the target will be sufficiently small to
allow for the creation of a short thunk. This is currently the case
for most thunks that we create, except for the last one, which could,
depending on the size of the output section, potentially appear near
the end and therefore have a relatively small amount of code after it.
This patch moves the last thunk section to ThunkSectionSpacing bytes
before the end of the output section, as long as the section is larger
than 2*ThunkSectionSpacing bytes. It reduces the size of Chromium
for Android's .text section by 32KB.
Differential Revision: https://reviews.llvm.org/D44966
llvm-svn: 328889
/FIXED:NO is always the default, so that part needs no work.
Also test the interaction of /ORDER: with /INCREMENTAL.
https://reviews.llvm.org/D45091
llvm-svn: 328877
As of rL215127, FileCheck has an -allow-empty flag,
so this could be used instead of writing a dummy line.
But it looks like the log is never empty now, so not
even that is needed.
llvm-svn: 328862
I tried a few different designs to find a way to implement it without
too much hassle and settled down with this. Unlike before, object files
given as arguments for --just-symbols are handled as object files, with
an exception that their section tables are handled as if they were all
null.
Differential Revision: https://reviews.llvm.org/D42025
llvm-svn: 328852
A short thunk uses a direct branch (b or b.w) instruction, and is used
when the target has the same thumbness as the thunk and is within
direct branch range (32MB for ARM, 16MB for Thumb-2). Reduces the
size of Chromium for Android's .text section by around 160KB.
Differential Revision: https://reviews.llvm.org/D44963
llvm-svn: 328846
There are two FPMs in an MSF file, the idea being that for
incremental updates you can write to the alternate one and then
atomically swap them on commit. LLVM defaulted to using FPM1
on the first commit, but this differs from Microsoft's behavior
which is to default to using FPM2 on the first commit. To
eliminate some byte-level file differences, this patch changes
LLVM's default to also be FPM2.
Additionally, LLVM was trying to be "smart" about marking FPM
pages allocated. In addition to marking every page belonging
to the alternate FPM as unallocated, LLVM also marked pages at
the end of the main FPM which were not needed as unallocated.
In order to match the behavior of Microsoft-generated PDBs, we
now always mark every FPM block as allocated, regardless of
whether it is in the main FPM or the alt FPM, and regardless of
whether or not it describes blocks which are actually in the file.
This has the side benefit of simplifying our code.
llvm-svn: 328812
The PLT retpoline support for X86 and X86_64 did not include the padding
when writing the header and entries. This issue was revealed when linker
scripts were used, as this disables the built-in behaviour of filling
the last page of executable segments with trap instructions. This
particular behaviour was hiding the missing padding.
Added retpoline tests with linker scripts.
Differential Revision: https://reviews.llvm.org/D44682
llvm-svn: 328777
This fixes pr36623.
The problem is that we have to parse versions out of names before LTO
so that LTO can use that information.
When we get the LTO produced .o files, we replace the previous symbols
with the LTO produced ones, but they still have @ in their names.
We could just trim the name directly, but calling parseSymbolVersion
to do it is simpler.
llvm-svn: 328738
This enables callback-style programming where the JavaScript environment
can call back into the Wasm environment using a function pointer
received from the module.
Differential Revision: https://reviews.llvm.org/D44427
llvm-svn: 328643
Some tools (dwarfdump for example) get confused by the current -O0 -r
output since it has multiple copies of .debug_str.
We cannot just merge sections with the same name as they can have
different sh_entsize.
We could have duplicated logic for merging sections based on name and
sh_entsize, but it seems better to just use the existing logic by
enabling optimizations.
llvm-svn: 328640
The Data member of synthetic section's is not valid and empty. The Data
member is required to be valid by ICF as it is used by ICF to determine
the equality of section contents. Therefore, exclude synthetic sections
from ICF.
Fixes bug PR36910.
Differential Revision: https://reviews.llvm.org/D44923
llvm-svn: 328624
When the target saves ElfSym::GlobalOffsetTable in the .got rather than
.got.plt, Target->GotHeaderEntriesNum states the number of extra entries
required in the .got. Rather than having to add Target->GotHeaderEntriesNum to
NumEntries in every function which refers to NumEntries, this patch changes the
initial value of NumEntries in the constructor.
Differential Revision: https://reviews.llvm.org/D44744
llvm-svn: 328559
Currently, we might have a bug with scripts like below:
.foo : ALIGN(8)
{
*(.foo)
} > ram
because do not expand the memory region when doing ALIGN.
This might result in file range overlaps. The patch fixes the issue.
Differential revision: https://reviews.llvm.org/D44730
llvm-svn: 328479
Currently when we build input sections list in linker script
we ignore all rel[a] sections. That was done to support
scripts like .rela.dyn : { *(.rela.data) } for emit relocs.
Though as a result following scripts were also silently ignored:
/DISCARD/ : { *(.rela.plt)
/DISCARD/ : { *(.rela.dyn)
and we produced output with this sections. That is not ideal.
The solution this patch suggests is simple: do not ignore synthetic
rel[a] sections. That way we can enable common discarding logic
for them and report a proper error.
Differential revision: https://reviews.llvm.org/D41640
llvm-svn: 328419
This was reverted several times due to what ultimately turned out
to be incompatibilities in our serialized hash table format.
Several changes went in prior to this to fix those issues since
they were more fundamental and independent of supporting injected
sources, so now that those are fixed this change should hopefully
pass.
llvm-svn: 328363
When investigating bugs in PDB generation, the first step is
often to do the same link with link.exe and then compare PDBs.
But comparing PDBs is hard because two completely different byte
sequences can both be correct, so it hampers the investigation when
you also have to spend time figuring out not just which bytes are
different, but also if the difference is meaningful.
This patch fixes a couple of cases related to string table emission,
hash table emission, and the order in which we emit strings that
makes more of our bytes the same as the bytes generated by MS PDBs.
Differential Revision: https://reviews.llvm.org/D44810
llvm-svn: 328348
When looking for the output section and the output offset the
expectation was that the caller had looked at Repl. That works fine
for InputSections, but in the case of MergeInputSections the caller
doesn't have the section that is actually replaced.
The original testcase was failing because getOutputSection was
returning null. The slightly extended testcase also checks that
getOffset also checks Repl.
I will send a refactoring separetelly.
llvm-svn: 328332
This fixes PR36367 which is about segfault when --emit-relocs is
used together with .eh_frame sections which happens because
of reordering of regular and .rel[a] sections.
Path changes loop that iterates over input sections to create
relocation target sections first.
Differential revision: https://reviews.llvm.org/D44679
llvm-svn: 328299
Currently lld just parses the .debug_line section assuming that there
is only one compile unit. That assumption is false (PR36793).
I have a patch that changes lld to iterate over the compile units and
parse the portions of the .debug_line they point to (which fixes
PR36793).
A problem is that we will then need a compiler unit pointing to
.debug_line for lld to see it.
It seems like bfd has the same restriction.
This patch updates existing tests to add a minimal compile unit so
that they still work with PR36793 fixed.
llvm-svn: 328215
The relocations R_PPC64_REL16_LO and R_PPC64_REL16_HA should return R_PC
for getRelExpr since they compute #lo(S + A – P) and #ha(S + A – P).
Differential Revision: https://reviews.llvm.org/D44648
llvm-svn: 328103
Patch teaches LLD to hint user about -fdebug-types-section flag
if relocation overflow happens in debug section.
Differential revision: https://reviews.llvm.org/D40954
llvm-svn: 328081
This is still failing on a different bot this time due to some
issue related to hashing absolute paths. Reverting until I can
figure it out.
llvm-svn: 328014
The issue causing this to fail in certain configurations
should be fixed.
It was due to the fact that DIA apparently expects there to be
a null string at ID 1 in the string table. I'm not sure why this
is important but it seems to make a difference, so set it.
llvm-svn: 328002
There are no reasons for them to be STV_DEFAULT,
recently bfd did the same change.
Differential revision: https://reviews.llvm.org/D44566
llvm-svn: 327983
It seems @LLVM_LIBXML2_ENABLED@ doesn't always get set to 0 when not available,
but to nothing, which broke parsing of lit.site.cfg.py.
> @LLVM_LIBXML2_ENABLED@ will be replaced with 0 or 1. Putting quotes
> around that is unnecessary and just makes it harder to use the value.
> This matches what have_zlib does below.
>
> This also puts the flag together with the feature-related ones instead
> of the path-related flags.
llvm-svn: 327966
@LLVM_LIBXML2_ENABLED@ will be replaced with 0 or 1. Putting quotes
around that is unnecessary and just makes it harder to use the value.
This matches what have_zlib does below.
This also puts the flag together with the feature-related ones instead
of the path-related flags.
llvm-svn: 327964
We do not have test showing we explicitly reject objects
where relocation section goes before the target, i.e
.rel[a].text is listed before .text, for example.
The patch adds it.
llvm-svn: 327963
Choosing a Shift2 value based on wordsize is cargo-culted from gold.
Assuming that djb hash is a good hash function, choosing bits [4,9]
shouldn't be any worse or better than choosing bits [5,10]. We shouldn't
have copied that behavior that we can't justify in the first place.
Differential Revision: https://reviews.llvm.org/D44547
llvm-svn: 327921
We found that when you pass --allow-multiple-definitions or `-z muldefs`
to GNU linkers, they don't complain about duplicate symbols at all. They
don't even print out warnings on it. We emit warnings in that case.
If you pass --fatal-warnings, that difference results in a link failure.
Differential Revision: https://reviews.llvm.org/D44549
llvm-svn: 327920
Natvis is a debug language supported by Visual Studio for
specifying custom visualizers. The /NATVIS option is an
undocumented link.exe flag which will take a .natvis file
and "inject" it into the PDB. This way, you can ship the
debug visualizers for a program along with the PDB, which
is very useful for postmortem debugging.
This is implemented by adding a new "named stream" to the
PDB with a special name of /src/files/<natvis file name>
and simply copying the contents of the xml into this file.
Additionally, we need to emit a single stream named
/src/headerblock which contains a hash table of embedded
files to records describing them.
This patch adds this functionality, including the /NATVIS
option to lld-link.
Differential Revision: https://reviews.llvm.org/D44328
llvm-svn: 327895
This patch adds changes to start supporting the Power 64-Bit ELF V2 ABI.
This includes:
- Changing the ElfSym::GlobalOffsetTable to be named .TOC.
- Creating a GotHeader so the first entry in the .got is .TOC.
- Setting the e_flags to be 1 for ELF V1 and 2 for ELF V2
Differential Revision: https://reviews.llvm.org/D44483
llvm-svn: 327871
This is the same as 327248 except Arm defining _GLOBAL_OFFSET_TABLE_ to
be the base of the .got section as some existing code is relying upon it.
For most Targets the _GLOBAL_OFFSET_TABLE_ symbol is expected to be at
the start of the .got.plt section so that _GLOBAL_OFFSET_TABLE_[0] =
reserved value that is by convention the address of the dynamic section.
Previously we had defined _GLOBAL_OFFSET_TABLE_ as either the start or end
of the .got section with the intention that the .got.plt section would
follow the .got. However this does not always hold with the current
default section ordering so _GLOBAL_OFFSET_TABLE_[0] may not be consistent
with the reserved first entry of the .got.plt.
X86, X86_64 and AArch64 will use the .got.plt. Arm, Mips and Power use .got
Fixes PR36555
Differential Revision: https://reviews.llvm.org/D44259
llvm-svn: 327823
This change broke ARM code that expects to be able to add
_GLOBAL_OFFSET_TABLE_ to the result of an R_ARM_REL32.
I will provide a reproducer on llvm-commits.
llvm-svn: 327688
In COFF, duplicate string literals are merged by placing them in a
comdat whose leader symbol name contains a specific prefix followed
by the hash and partial contents of the string literal. This gives
us an easy way to identify sections containing string literals in
the linker: check for leader symbol names with the given prefix.
Any sections that are identified in this way as containing string
literals may be tail merged. We do so using the StringTableBuilder
class, which is also used to tail merge string literals in the ELF
linker. Tail merging is enabled only if ICF is enabled, as this
provides a signal as to whether the user cares about binary size.
Differential Revision: https://reviews.llvm.org/D44504
llvm-svn: 327668
Patch teaches LLD to print BYTE/SHORT/LONG/QUAD and
location move commands to the map file.
Differential revision: https://reviews.llvm.org/D44004
llvm-svn: 327612
I definitely didn't run the tests before committing :(
Most of these tests failed because the LLD map file output changed,
moving the functions from the main text section to a new per-function
section.
ICF also started to fire in a few cases, leading to new layouts.
llvm-svn: 327571
This is an option to print out a table of symbols and filenames.
The output format of this option is the same as GNU, so that it can be
processed by the same scripts as before after migrating from GNU to lld.
This option is mildly useful; we can live without it. But it is pretty
convenient sometimes, and it can be implemented in 50 lines of code, so
I think lld should support this option.
Differential Revision: https://reviews.llvm.org/D44336
llvm-svn: 327565
GNU ld has got a number of different flags for adjusting how to
behave around stdcall functions. The --kill-at flag strips the
trailing sdcall suffix from exported functions (which otherwise
is included by default in MinGW setups).
This also strips it from the corresponding import library though.
That makes it hard to link to such an import library from code
that calls the functions - but this matches what GNU ld does with
this flag. Therefore, this flag is probably not sensibly used
together with import libraries, but probably mostly when creating
some sort of plugin, or if creating the import library separately
with dlltool.
Differential Revision: https://reviews.llvm.org/D44292
llvm-svn: 327561
This tests that LLVM emits the relocations that /guard:cf needs to
identify address taken.
This was PR36624, which was fixed in r327557.
llvm-svn: 327559
This "fixes" PR36678 by just producing an error when we find a case
where we would produce an plt entry that used ebx but ebx would not be
set.
llvm-svn: 327542
Previously, Config->InitialMemory/MaxMemory were hooked up to some
commandline args but had no effect at all.
Differential Revision: https://reviews.llvm.org/D44393
llvm-svn: 327508
Currently, we can end up with NBuckets==0 and android loader
does not like it (PR36537).
Seems we can go with a minimal amount of changes here for simplicity
and be consistent with gold and so just always use >= 1 value for NBuckets.
Differential revision: https://reviews.llvm.org/D44422
llvm-svn: 327481
Patch do the following changes:
* Test case was converted from MIPS to x86.
* Removed part of the test checking we are able to produce a valid output.
Since we do that already in other tests, this one's intention should be
only to check we are still able to report overlaps and/or produce
broken output with overlaps.
Differential revision: https://reviews.llvm.org/D44438
llvm-svn: 327480
This fixes issues found on the wasm waterfall related to relocations
with addends. Undefined symbols, even those with addends should
always have a provisional value of zero. At least this is what llvm
emits (and I believe this is true for ELF too).
Differential Revision: https://reviews.llvm.org/D44451
llvm-svn: 327468
This follows recently started direction and sometimes
allows to fully get rid from `echo` calls.
I'll rename changed files to *.test in a follow-up.
llvm-svn: 327410
Previously, Config->Demangle was uninitialised (not hooked up to
commandline handling)
Differential Revision: https://reviews.llvm.org/D44301
llvm-svn: 327390
This finishes PR35877.
INSERT BEFORE used similar to INSERT AFTER,
it inserts sections before the given target section.
Differential revision: https://reviews.llvm.org/D44380
llvm-svn: 327378
This is part of PR36515.
With some linkerscripts it is possible to get file offset overlaps
and overflows. Currently LLD checks overlaps in checkNoOverlappingSections().
And also we allow broken output with --no-inhibit-exec.
Problem is that sometimes final offset of sections is completely broken
and we calculate output file size wrong and might crash.
Patch implements check to verify that there is no output section
which offset exceeds file size.
Differential revision: https://reviews.llvm.org/D43819
llvm-svn: 327376
This fixes PR36598.
LLD currently crashes when we have empty output section
with SHF_LINK_ORDER flag. This might happen if we place an
empty synthetic section in the linker script, but keep output
section alive with the use of additional symbol, for example.
The patch fixes the issue by dropping all special flags
for empty sections.
Differential revision: https://reviews.llvm.org/D44376
llvm-svn: 327374
Currently lld creates plain plt entries when a R_386_PC32 resolves to
a symbol in a shared library. That is a bug (PR36678). Don't depend on
that behavior on this test.
llvm-svn: 327357
This bug was found by accident while trying to expand out testcases
for imported symbols, and is covered by the additional test case.
Differential Revision: https://reviews.llvm.org/D44331
llvm-svn: 327290
This matches the existing ordering that's been there for globals
for a while (__stack_pointer coming first).
Differential Revision: https://reviews.llvm.org/D44333
llvm-svn: 327286
This makes the output of some flag names in warning messages consistent with
the output of /? and the output of flags in most other diagnostics.
https://reviews.llvm.org/D44307
llvm-svn: 327261
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
the start of the .got.plt section so that _GLOBAL_OFFSET_TABLE_[0] =
reserved value that is by convention the address of the dynamic section.
Previously we had defined _GLOBAL_OFFSET_TABLE_ as either the start or end
of the .got section with the intention that the .got.plt section would
follow the .got. However this does not always hold with the current
default section ordering so _GLOBAL_OFFSET_TABLE_[0] may not be consistent
with the reserved first entry of the .got.plt.
X86, X86_64, Arm and AArch64 will use the .got.plt. Mips and Power use .got
Fixes PR36555
Differential Revision: https://reviews.llvm.org/D44259
llvm-svn: 327248
This avoids creating multiple thunks for symbols with aliases or which
belong to ICF'd sections. This patch reduces the size of Chromium for
Android by 260KB (0.8% of .text).
Differential Revision: https://reviews.llvm.org/D44284
llvm-svn: 327154
This error case is described in Linking.md. The operand for call requires
generation of a synthetic stub.
Differential Revision: https://reviews.llvm.org/D44028
llvm-svn: 327151
This fixes the broken tests that were causing failures. The tests
before were verifying that the time stamp was 0, but now that we
are actually writing a timestamp, I just removed the match against
the timestamp value.
llvm-svn: 327049
Our code assumes all input sections in an output SHF_LINK_ORDER
section has SHF_LINK_ORDER flag. We do not check that and that can cause a crash.
That happens because we call
std::stable_sort(Sections.begin(), Sections.end(), compareByFilePosition);,
where compareByFilePosition predicate does not expect to see
null when calls getLinkOrderDep.
The same might happen when sections refer to non-regular sections.
Test cases demonstrate the issues, patch fixes them.
Differential revision: https://reviews.llvm.org/D44193
llvm-svn: 327006
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
When a symbol is exported via --export=foo but --allow-undefined
is also specified, the symbol is now allowed to be undefined.
Previously we were special casing such symbols.
This combinations of behavior is exactly what emescripten
requires. Although we are trying hard not to allow emscripten
specific features in lld, this one makes sense.
Enforce this behavior by added this case to test/wasm/undefined.ll.
Differential Revision: https://reviews.llvm.org/D44237
llvm-svn: 326976
It was raised during the review of D43819.
LLD usually use [X, Y] for reporting ranges, like below:
"relocation R_386_16 out of range: 65536 is not in [0, 65535]"
Patch changes rangeToString() to do the same.
Differential revision: https://reviews.llvm.org/D44207
llvm-svn: 326918
Summary:
I originally tried to simplify code and then noticed that lld doesn't
do what it tells to the user by warn(). It says "unable to order
discarded symbol" but it actually can for sections eliminated by ICF.
With this patch, lld doesn't sort such sections.
Reviewers: jhenderson, rafael
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D44180
llvm-svn: 326911
LLD uses the debug info and debug line sections to determine the location of
e.g. references to undefined symbols, when producing error messages. In the
event that debug info was present, but debug line parsing failed for some
reason, then a nullptr would end up being dereferenced by the location-lookup
code.
Differential Revision: https://reviews.llvm.org/D44205
Reviewers: grimar
llvm-svn: 326899
With fix: add missing "RUN:" prefix to test case.
Original commit message:
We do not report LMA region overflows currently.
Both GNU linkers do that. The patch implements it.
Differential revision: https://reviews.llvm.org/D44094
llvm-svn: 326895
We do not report LMA region overflows currently.
Both GNU linkers do that. The patch implements it.
Differential revision: https://reviews.llvm.org/D44094
llvm-svn: 326892
Currently, LLD segfaults when linker script attempts to discard
one of the hash sections. This patch fixes that.
Differential revision: https://reviews.llvm.org/D44012
llvm-svn: 326891
It looks like the problem that caused us to originally warn instead of
error was that of a symbol being assigned to the same version twice.
Now we don't warn if a symbol is assigned to the same version twice,
but error if it is assigned to multiple.
This fixes pr28342.
llvm-svn: 326813
We do not expand memory region correctly for following scripts:
.foo.1 :
{
*(.foo.1)
. += 0x1000;
} > ram
Patch generalizes expanding of output sections and memory
regions in one place and fixes the issue.
Differential revision: https://reviews.llvm.org/D43999
llvm-svn: 326688
"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
LLD can not catch a memory area overflow when using a data command.
If we have the script below:
.foo :
{
*(.foo)
BYTE(0x1)
} > ram
where BYTE overflows the ram region, we do not report it currently.
Patch fixes that.
Differential revision: https://reviews.llvm.org/D43948
llvm-svn: 326545
GNU linkers by convention supports both `--foo bar` and `--foo=bar` styles
for all long options that take arguments.
Differential Revision: https://reviews.llvm.org/D43972
llvm-svn: 326506
Summary:
If an executable needs text relocations, it should be marked as such so
that the loader can prepare for text relocations. We currently create a
dummy segment with DT_TEXTREL for that purpose.
Generic ABI as of 2000 [1] mentioned that "Its [DT_TEXTREL's] use
has been superseded by the DF_TEXTREL flag". However, it's actually not
superseded even after 18 years. OpenBSD and musl recognize only DT_TEXTREL.
So we still need to set both.
[1] http://www.sco.com/developers/gabi/2000-07-17/ch5.dynamic.html
Reviewers: rafael
Subscribers: emaste, llvm-commits, arichardson
Differential Revision: https://reviews.llvm.org/D43920
llvm-svn: 326503
With the current code if the script has a PHDRS we always obey and try
to allocate a header. This can cause Min - HeaderSize to underflow.
It looks like bfd actually prints an error for this case. With this
patch we do the same.
Found while looking at pr36515.
llvm-svn: 326441
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
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
Previously, we didn't try to make effort to put .note sections next
to each other in the output file, so two .note sections were likely
to be stored to two separate NOTE segments. That's undesirable because
we should create as few segments as possible in general.
Differential Revision: https://reviews.llvm.org/D43858
llvm-svn: 326410
It now includes both linkerscript and non linkerscript variants.
Extracted from a patch by Rui while I was trying to figure out what
exactly was changing.
llvm-svn: 326409
Summary:
This change removes large "echo" commands from the test by writing
tests themselves as linker scripts.
Reviewers: rafael
Subscribers: emaste, javed.absar, llvm-commits, arichardson
Differential Revision: https://reviews.llvm.org/D43900
llvm-svn: 326403
Some linker script test cases contain only a few lines of assembly
and a long linker script. Such tests are easier to maintain if we
write the main test file as a linkier script instead of assembly.
Differential Revision: https://reviews.llvm.org/D43887
llvm-svn: 326363
Update LLD test expectations for new symbol ordering introduced by
Differential D43685.
Differential Revision: https://reviews.llvm.org/D43875
llvm-svn: 326335
We should process symbols inside output section declarations the same way as top-level ones.
Differential Revision: https://reviews.llvm.org/D43008
llvm-svn: 326305
This means we don't need to write the linking metadata section
at all for executable (non-relocatable) output.
Differential Revision: https://reviews.llvm.org/D42869
llvm-svn: 326268
Summary:
Some of the tests invoke llvm-readelf. This currently appears to work
probably because the LLVM binary directory is included in $PATH. However,
this is quite fragile so let's just make lit expand the full path.
Reviewers: ruiu, espindola
Reviewed By: ruiu
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43827
llvm-svn: 326257
Imagine that we have sections A, B, C, where A == C and
symbol ordering file containing symbols: symC, symB, symA
Previously because of ICF it was possible that final order would be
B, A or B, C. That violates order specified in ordering file.
Patch changes that.
Differential revision: https://reviews.llvm.org/D43234
llvm-svn: 326179
It should be possible to resolve undefined symbols in dynamic libraries
using symbols defined in a linker script.
Differential Revision: https://reviews.llvm.org/D43011
llvm-svn: 326176
Peter Smith