If input relocation records have RELA format while output dynamic
relocations have REL format the only way to transfer a dynamic
relocation addendum is to save it into the location modified by
the dynamic relocation.
llvm-svn: 233532
Setting _alignment member varaible to 0 look suspicious since
the minimum alignment value is 1. I'm not going to change that
number in this patch, though.
llvm-svn: 233472
The fix is for r233277. This makes tests work.
On some build bots the test failed due to different llvm-objdump behaviour for target detection.
Now test checks .text section with etalon and illustrates correctness of generated
code without using of -disassemble llvm-objdump option.
llvm-svn: 233463
If HAVE_CXXABI_H is not defined, this function is the identity function.
Because HAVE_CXXABI_H did not protect the entire function, it did
extra stuffs before returning the argument.
The new code calls fewer functions. This should help developers understand
this piece of code.
llvm-svn: 233460
I expected that these functions are overridden somewhere in the LLD
code base, but they are actually not. Removing virtual for readability
(and performance).
llvm-svn: 233441
Use of llvm::Optional seems useless here because we can set the
default value 0x1000 as an initial value to the varaible.
This patch also de-virtualize the accessor functions.
llvm-svn: 233438
No one uses return value of the member function, and return value
is always true. Returning a value doesn't make sense.
This patch also de-virtualize the fucntion.
llvm-svn: 233436
This diff includes implementation of linking calls to ifunc functions.
It provides ifunc entries in PLT and corresponding relocations (R_ARM_ALU_PC_G0_NC,
R_ARM_ALU_PC_G1_NC, R_ARM_LDR_PC_G2 for link-time and R_ARM_IRELATIVE for run-time).
Differential Revision: http://reviews.llvm.org/D7833
llvm-svn: 233277
Mapping symbols should have their own code models,
and in some places must be treated in a specific way.
Make $t denote Thumb code, and $a and $d denote ARM code.
Set size, binding and type of mapping symbols to what the specification says.
Differential Revision: http://reviews.llvm.org/D8601
llvm-svn: 233259
This patch defines implicit conversion between integers and PowerOf2
instances, so uses of the classes is now implicit and look like
regular integers. Now we are ready to remove the scaffolding.
llvm-svn: 233245
The new constructor's type is the same, but this one takes not a log2
value but an alignment value itself, so the meaning is totally differnet.
llvm-svn: 233244
This patch is to make instantiation and conversion to an integer explicit,
so that we can mechanically replace all occurrences of the class with
integer in the next step.
Now get() returns an alignment value rather than its log2 value.
llvm-svn: 233242
We are using log2 values and values themselves to represent alignments.
For example, alignment 8 is sometimes represented as 3 (8 == 2^3).
We want to stop using log2 values.
Because both types are regular arithmetic types, we cannot get help from
a compiler to find places we mix two representations. That makes this
merging work surprisingly hard because if I make a mistake, I'll just get
wrong results at runtime (Yay types!). In this patch, I introduced
a class to represents power-of-two values, which is basically an alias
for an integer type.
Once the migration is done, the class will be removed.
llvm-svn: 233232
Import Lookup Table in Import Directory Table has the same contents
as Hint/Name Table. Symbol names imported from DLLs are pointed by
both Import Directory Table and Hint/Name Table. We had duplicate
strings there.
This patch eliminates that duplication to make the table smaller.
This should reduce binary size by the sum of lengths of imported
symbols.
llvm-svn: 233128
Visual C++ shows the "right shift by too large amount" warning if
`MipsELFReference` is instantiated for 32-bit target and `Elf_Rel_Impl::getType`
method has `unsigned char` return type. We can freely suppress the warning in
that case because MIPS 32-bit ABI does not pack multiple relocation types into
the single field `r_type` and the `MipsELFReference::_tag` should be always
zero in that case.
No functional changes.
llvm-svn: 233088
N64 ABI relocation record r_info field in fact consists of five subfields:
* r_sym - symbol index
* r_ssym - special symbol
* r_type3 - third relocation type
* r_type2 - second relocation type
* r_type - first relocation type
Up to three these relocations applied one by one. The first relocation
uses an addendum from the relocation record. Each subsequent relocation
takes as its addend the result of the previous operation. Only the final
operation actually modifies the location relocated. The first relocation
uses as a reference symbol specified by the `r_sym` field. The third
relocation assumes NULL symbol.
The patch represents these data using LLD model and takes in account
additional relocation types during a relocation calculation.
Additional relocations do not introduce any new relations between two
atoms and just specify operations need to be done during a relocation
calculation. The first relocation type (`r_type`) stored in the
`Reference::_kindValue`. The rest of relocations and `r_ssym` value are
stored in the new `Reference::_tag` field "as-is". I decided to do not
"decode" these data on the core LLD level to prevent pollution of the
core LLD model by very target specific data.
Also I have to override writing of relocation records in the `RelocationTable`
class to convert MIPS N64 ABI relocation information from the `Reference`
class back to the ELF relocation record.
http://reviews.llvm.org/D8533
llvm-svn: 233057
The aforementioned relocation generate a GOT entry with a
R_X86_64_TPOFF64. The new relocation is processed at startup
time by the loader. lld didn't generate the outstanding relocation,
now it does. This bug was found while trying to link ls(1) on FreeBSD.
Simplified repro:
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>
int
main(void)
{
wchar_t wc = 98;
if (!iswprint(wc))
printf("blah\n");
else
printf("foo\n");
return (0);
}
which incorrectly outputs "blah" when linked with lld before this patch.
llvm-svn: 233051
separately
This change reduce difference between the trunk and upcoming patch and
simplify the future code review.
No functional changes.
llvm-svn: 232919
This changes improves performance of lld, when self-hosting lld, when compared
with the bfd linker. BFD linker on average takes 8 seconds in elapsed time.
lld takes 3 seconds elapased time average. Without this change, lld takes ~5
seconds average. The runtime comparisons were done on a release build and
measured by running linking thrice.
lld self-host without the change
----------------------------------
real 0m3.196s
user 0m4.580s
sys 0m0.832s
lld self-host with lld
-----------------------
user 0m3.024s
user 0m3.252s
sys 0m0.796s
time taken to build lld with bfd
--------------------------------
real 0m8.419s
user 0m7.748s
sys 0m0.632s
llvm-svn: 232460
I knew I cut corners when I wrote this. Turned out that it is
actually slow when a file being read has many symbols. This patch
is to stop doing linear search and instead do map lookup.
llvm-svn: 232436
This adds a parallel_for_each similar to functionality in MSVC concurrency
library.
This was very patiently reviewed by Rui and credits go to him for this patch.
Differential Revision: http://reviews.llvm.org/D8348
llvm-svn: 232419
The `eh_frame_ptr` field in the `.eh_frame_hdr` section contains an address
of the `.eh_frame` section. Using an absolute 32-bit format for encoding
of this field does not work for 64-bit targets. It is better to use a
relative format because it covers both 32-bit and 64-bit cases. Sure
this work if a distance between `.eh_frame_hdr` and `.eh_frame` sections
is less than 4 Gb but it is a rather correct assumption.
http://reviews.llvm.org/D8352
llvm-svn: 232414
Puts symbols defined in linker script expressions in a runtime file that is
added as input to the resolver, making the input object files see symbols
defined in linker scripts.
http://reviews.llvm.org/D8263
llvm-svn: 232409
Denis Protivensky