The '.set mips64' directive enables the feature Mips:FeatureMips64
from assembly. Note that it doesn't modify the ELF header as opposed
to the use of -mips64 from the command-line. The reason for this
is that we want to be as compatible as possible with existing assemblers
like GAS.
llvm-svn: 204817
The '.set mips64r2' directive enables the feature Mips:FeatureMips64r2
from assembly. Note that it doesn't modify the ELF header as opposed
to the use of -mips64r2 from the command-line. The reason for this
is that we want to be as compatible as possible with existing assemblers
like GAS.
llvm-svn: 204815
The directive '.option pic2' enables PIC from assembly source.
At the moment none of the macros/directives check the PIC bit
but that's going to be fixed relatively soon. For example, the
expansion of macros like 'la' depend on the relocation model.
llvm-svn: 204803
These are aliases of t4-t7 and are provided for compatibility with both the
original ABI documentation (using t4-t7) and GNU As (using t0-t3)
llvm-svn: 204797
Summary: Added test cases for O32 and N32 on MIPS64.
Reviewers: matheusalmeida
Reviewed By: matheusalmeida
Differential Revision: http://llvm-reviews.chandlerc.com/D3175
llvm-svn: 204796
This reveals a small mistake in mips-register-names.s ($sp is tested twice and
$s8 is not tested) which will be fixed in a follow-up commit.
llvm-svn: 204792
We need .symtab_shndxr if and only if a symbol references a section with an
index >= 0xff00.
The old code was trying to figure out if the section was needed ahead of time,
making it a fairly dependent on the code actually writing the table. It was
also somewhat conservative and would create the section in cases where it was
not needed.
If I remember correctly, the old structure was there so that the sections were
created in the same order gas creates them. That was valuable when MC's support
for ELF was new and we tested with elf-dump.py.
This patch refactors the symbol table creation to another class and makes it
obvious that .symtab_shndxr is really only created when we are about to output
a reference to a section index >= 0xff00.
While here, also improve the tests to use macros. One file is one section
short of needing .symtab_shndxr, the second one has just the right number.
llvm-svn: 204769
Summary:
Remove the XFAIL added in my previous commit and correct the test such that
it correctly tests the expansion of the assembler temporary.
Also added a test to check that $at is always $1 when written by the
user.
Corrected the new assembler temporary warnings so that they are emitted for
numeric registers too.
Differential Revision: http://llvm-reviews.chandlerc.com/D3169
llvm-svn: 204711
Summary:
The assembler temporary is normally $at ($1) but can be reassigned using
'.set at=$reg'. Regardless of which register is nominated as the assembler
temporary, $at remains $1 when written by the user.
Adds warnings under the following conditions:
* The register nominated as the assembler temporary is used by the user.
* '.set noat' is in effect and $at is used by the user.
Both of these only work for named registers. I have a follow up commit that makes it work for numeric registers as well.
XFAIL set-at-directive.s since it incorrectly tests that $at is redefined by
'.set at=$reg'. Testcases will follow in a separate commit.
Patch by David Chisnall
His work was sponsored by: DARPA, AFRL
Differential Revision: http://llvm-reviews.chandlerc.com/D3167
llvm-svn: 204710
As a first step towards real little-endian code generation, this patch
changes the PowerPC MC layer to actually generate little-endian object
files. This involves passing the little-endian flag through the various
layers, including down to createELFObjectWriter so we actually get basic
little-endian ELF objects, emitting instructions in little-endian order,
and handling fixups and relocations as appropriate for little-endian.
The bulk of the patch is to update most test cases in test/MC/PowerPC
to verify both big- and little-endian encodings. (The only test cases
*not* updated are those that create actual big-endian ABI code, like
the TLS tests.)
Note that while the object files are now little-endian, the generated
code itself is not yet updated, in particular, it still does not adhere
to the ELFv2 ABI.
llvm-svn: 204634
Summary:
These expressions already worked but weren't tested.
Patch by Robert N. M. Watson and David Chisnall (it was originally two patches)
Their work was sponsored by: DARPA, AFRL
Differential Revision: http://llvm-reviews.chandlerc.com/D3156
llvm-svn: 204612
Summary:
- If only two registers are passed to a three-register operation, then the
first argument is both source and destination register.
- If a non-register is passed as the last argument, generate the immediate
version of the instruction.
Also mark DADD commutative and add scheduling information (to the generic
scheduler), and implement DSUB.
Patch by David Chisnall
His work was sponsored by: DARPA, AFRL
CC: theraven
Differential Revision: http://llvm-reviews.chandlerc.com/D3148
llvm-svn: 204605
This is similar, but not identical to what gas does. The logic in MC is to just
compute the symbol table after parsing the entire file. GAS is mixed, given
.type b, @object
a = b
b:
.type b, @function
It will propagate the change and make 'a' a function. Given
.type b, @object
b:
a = b
.type b, @function
the type of 'a' is still object.
Since we do the computation in the end, we produce a function in both cases.
llvm-svn: 204555
When a label is parsed, check if there is type information available for the
label. If so, check if the symbol is a function. If the symbol is a function
and we are in thumb mode and no explicit thumb_func has been emitted, adjust the
symbol data to indicate that the function definition is a thumb function.
The application of this inferencing is improved value handling in the object
file (the required thumb bit is set on symbols which are thumb functions). It
also helps improve compatibility with binutils.
The one complication that arises from this handling is the MCAsmStreamer. The
default implementation of getOrCreateSymbolData in MCStreamer does not support
tracking the symbol data. In order to support the semantics of thumb functions,
track symbol data in assembly streamer. Although O(n) in number of labels in
the TU, this is already done in various other streamers and as such the memory
overhead is not a practical concern in this scenario.
llvm-svn: 204544
The Octeon cpu from Cavium Networks is mips64r2 based and has an extended
instruction set. In order to utilize this with LLVM, a new cpu feature "octeon"
and a subtarget feature "cnmips" is added. A small set of new instructions
(baddu, dmul, pop, dpop, seq, sne) is also added. LLVM generates dmul, pop and
dpop instructions with option -mcpu=octeon or -mattr=+cnmips.
llvm-svn: 204337
Given
bar = foo + 4
.long bar
MC would eat the 4. GNU as includes it in the relocation. The rule seems to be
that a variable that defines a symbol is used in the relocation and one that
does not define a symbol is evaluated and the result included in the relocation.
Fixing this unfortunately required some other changes:
* Since the variable is now evaluated, it would prevent the ELF writer from
noticing the weakref marker the elf streamer uses. This patch then replaces
that with a VariantKind in MCSymbolRefExpr.
* Using VariantKind then requires us to look past other VariantKind to see
.weakref bar,foo
call bar@PLT
doing this also fixes
zed = foo +2
call zed@PLT
so that is a good thing.
* Looking past VariantKind means that the relocation selection has to use
the fixup instead of the target.
This is a reboot of the previous fixes for MC. I will watch the sanitizer
buildbot and wait for a build before adding back the previous fixes.
llvm-svn: 204294
Allow object files to be tagged with a version-min load command for iOS
or MacOSX.
Teach macho-dump to understand the version-min load commands for
testcases.
rdar://11337778
llvm-svn: 204190
The revision I'm reverting breaks handling of transitive aliases. This blocks us
and breaks sanitizer bootstrap:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/2651
(and checked locally by Alexey).
This revision is the result of:
svn merge -r204059:204058 -r204028:204027 -r203962:203961 .
+ the regression test added to test/MC/ELF/alias.s
Another way to reproduce the regression with clang:
$ cat q.c
void a1();
void a2() __attribute__((alias("a1")));
void a3() __attribute__((alias("a2")));
void a1() {}
$ ~/work/llvm-build/bin/clang-3.5-good -c q.c && mv q.o good.o && \
~/work/llvm-build/bin/clang-3.5-bad -c q.c && mv q.o bad.o && \
objdump -t good.o bad.o
good.o: file format elf64-x86-64
SYMBOL TABLE:
0000000000000000 l df *ABS* 0000000000000000 q.c
0000000000000000 l d .text 0000000000000000 .text
0000000000000000 l d .data 0000000000000000 .data
0000000000000000 l d .bss 0000000000000000 .bss
0000000000000000 l d .comment 0000000000000000 .comment
0000000000000000 l d .note.GNU-stack 0000000000000000 .note.GNU-stack
0000000000000000 l d .eh_frame 0000000000000000 .eh_frame
0000000000000000 g F .text 0000000000000006 a1
0000000000000000 g F .text 0000000000000006 a2
0000000000000000 g F .text 0000000000000006 a3
bad.o: file format elf64-x86-64
SYMBOL TABLE:
0000000000000000 l df *ABS* 0000000000000000 q.c
0000000000000000 l d .text 0000000000000000 .text
0000000000000000 l d .data 0000000000000000 .data
0000000000000000 l d .bss 0000000000000000 .bss
0000000000000000 l d .comment 0000000000000000 .comment
0000000000000000 l d .note.GNU-stack 0000000000000000 .note.GNU-stack
0000000000000000 l d .eh_frame 0000000000000000 .eh_frame
0000000000000000 g F .text 0000000000000006 a1
0000000000000000 g F .text 0000000000000006 a2
0000000000000000 g .text 0000000000000000 a3
llvm-svn: 204137
This performs the equivalent of a .set directive in that it creates a symbol
which is an alias for another symbol or value which may possibly be yet
undefined. This directive also has the added property in that it marks the
aliased symbol as being a thumb function entry point, in the same way that the
.thumb_func directive does.
The current implementation fails one test due to an unrelated issue. Functions
within .thumb sections are not marked as thumb_func. The result is that
the aliasee function is not valued correctly.
llvm-svn: 204059
Matheus Almeida