Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.
If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.
The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.
In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.
This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.
lab1: ; this will cause the lower order bit to be added
lab2=. ; this will not cause the lower order bit to be added
In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.
To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.
For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX"
labels.
Mips overrides the debug label suffix from ":" to "=." .
This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.
Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.htmlhttp://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html
llvm-svn: 170279
The linker will call `lto_codegen_add_must_preserve_symbol' on all globals that
should be kept around. The linker will pretend that a dylib is being created.
<rdar://problem/12528059>
llvm-svn: 169770
This function sets the `_exportDynamic' ivar. When that's set, we export all
symbols (e.g. we don't run the internalize pass). This is equivalent to the
`--export-dynamic' linker flag in GNU land:
--export-dynamic
When creating a dynamically linked executable, add all symbols to the dynamic
symbol table. The dynamic symbol table is the set of symbols which are visible
from dynamic objects at run time. If you do not use this option, the dynamic
symbol table will normally contain only those symbols which are referenced by
some dynamic object mentioned in the link. If you use dlopen to load a dynamic
object which needs to refer back to the symbols defined by the program, rather
than some other dynamic object, then you will probably need to use this option
when linking the program itself.
The Darwin linker will support this via the `-export_dynamic' flag. We should
modify clang to support this via the `-rdynamic' flag.
llvm-svn: 169656
Again, tools are trickier to pick the main module header for than
library source files. I've started to follow the pattern of using
LLVMContext.h when it is included as a stub for program source files.
llvm-svn: 169252
Necessary to give disassembler users (like darwin's otool) a possibility to
dlopen libLTO and still initialize the required LLVM bits. This used to go
through libMCDisassembler but that's a gross layering violation, the MC layer
can't pull in functions from the targets. Adding a function to libLTO is a bit
of a hack but not worse than exposing other disassembler bits from libLTO.
Fixes PR14362.
llvm-svn: 168545
Per the October 12, 2012 Proposal for annotated disassembly output sent out by
Jim Grosbach this set of changes implements this for X86 and arm. The llvm-mc
tool now has a -mdis option to produced the marked up disassembly and a couple
of small example test cases have been added.
rdar://11764962
llvm-svn: 166445
The TargetTransform changes are breaking LTO bootstraps of clang. I am
working with Nadav to figure out the problem, but I am reverting it for now
to get our buildbots working.
This reverts svn commits: 165665 165669 165670 165786 165787 165997
and I have also reverted clang svn 165741
llvm-svn: 166168
This is a temporary hack until Bill's project to record command line options
in the LLVM IR is ready. Clang currently sets a default CPU but that isn't
recorded anywhere and it doesn't get used in the final LTO compilation.
llvm-svn: 165809
make it more consistent with its intended semantics.
The `linker_private_weak_def_auto' linkage type was meant to automatically hide
globals which never had their addresses taken. It has nothing to do with the
`linker_private' linkage type, which outputs the symbols with a `l' (ell) prefix
among other things.
The intended semantic is more like the `linkonce_odr' linkage type.
Change the name of the linkage type to `linkonce_odr_auto_hide'. And therefore
changing the semantics so that it produces the correct output for the linker.
Note: The old linkage name `linker_private_weak_def_auto' will still parse but
is not a synonym for `linkonce_odr_auto_hide'. This should be removed in 4.0.
<rdar://problem/11754934>
llvm-svn: 162114
When the command line target options were removed from the LLVM libraries, LTO
lost its ability to specify things like `-disable-fp-elim'. Add this back by
adding the command line variables to the `lto' project.
<rdar://problem/12038729>
llvm-svn: 161353
There are some that I didn't remove this round because they looked like
obvious stubs. There are dead variables in gtest too, they should be
fixed upstream.
llvm-svn: 158090
This broke in r144788 when the CodeGenOpt option was moved from everywhere else
(specifically, from addPassesToEmitFile) to createTargetMachine. Since
LTOCodeGenerator wasn't passing the 4th argument, when the 4th parameter became
the 3rd, it silently continued to compile (int->bool conversion) but meant
something completely different.
This change preserves the existing (accidental) and previous (default)
semantics of the addPassesToEmitFile and restores the previous/intended
CodeGenOpt argument by passing it appropriately to createTargetMachine.
(discovered by pending changes to -Wconversion to catch constant->bool
conversions)
llvm-svn: 157705
so we don't want it to show up in the stable 3.1 interface.
While at it, add a comment about why LTOCodeGenerator manually creates the
internalize pass.
llvm-svn: 154807
Consider the following program:
$ cat main.c
void foo(void) { }
int main(int argc, char *argv[]) {
foo();
return 0;
}
$ cat bundle.c
extern void foo(void);
void bar(void) {
foo();
}
$ clang -o main main.c
$ clang -o bundle.so bundle.c -bundle -bundle_loader ./main
$ nm -m bundle.so
0000000000000f40 (__TEXT,__text) external _bar
(undefined) external _foo (from executable)
(undefined) external dyld_stub_binder (from libSystem)
$ clang -o main main.c -O4
$ clang -o bundle.so bundle.c -bundle -bundle_loader ./main
Undefined symbols for architecture x86_64:
"_foo", referenced from:
_bar in bundle-elQN6d.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
The linker was told that the 'foo' in 'main' was 'internal' and had no uses, so
it was dead stripped.
Another situation is something like:
define void @foo() {
ret void
}
define void @bar() {
call asm volatile "call _foo" ...
ret void
}
The only use of 'foo' is inside of an inline ASM call. Since we don't look
inside those for uses of functions, we don't specify this as a "use."
Get around this by not invoking the 'internalize' pass by default. This is an
admitted hack for LTO correctness.
<rdar://problem/11185386>
llvm-svn: 154124
reflected in the LLVM IR (as a declare or something), then treat it like a data
object.
N.B. This isn't 100% correct. The ASM parser should supply more information so
that we know what type of object it is, and what attributes it should have.
llvm-svn: 153870
Module-level ASM may contain definitions of functions and globals. However, we
were not telling the linker that these globals had definitions. As far as it was
concerned, they were just declarations.
Attempt to resolve this by inserting module-level ASM functions and globals into
the '_symbol' set so that the linker will know that they have values.
This gets us further towards our goal of compiling LLVM, but it still has
problems when linking libLTO.dylib because of the `-dead_strip' flag that's
passed to the linker.
<rdar://problem/11124216>
llvm-svn: 153638
but with a critical fix to the SelectionDAG code that optimizes copies
from strings into immediate stores: the previous code was stopping reading
string data at the first nul. Address this by adding a new argument to
llvm::getConstantStringInfo, preserving the behavior before the patch.
llvm-svn: 149800
This is the initial checkin of the basic-block autovectorization pass along with some supporting vectorization infrastructure.
Special thanks to everyone who helped review this code over the last several months (especially Tobias Grosser).
llvm-svn: 149468
file error checking. Use that to error on an unfinished cfi_startproc.
The error is not nice, but is already better than a segmentation fault.
llvm-svn: 147717
change, now you need a TargetOptions object to create a TargetMachine. Clang
patch to follow.
One small functionality change in PTX. PTX had commented out the machine
verifier parts in their copy of printAndVerify. That now calls the version in
LLVMTargetMachine. Users of PTX who need verification disabled should rely on
not passing the command-line flag to enable it.
llvm-svn: 145714
- On COFF the .lcomm directive has an alignment argument.
- On ELF we fall back to .local + .comm
Based on a patch by NAKAMURA Takumi.
Fixes PR9337, PR9483 and PR10128.
llvm-svn: 138976
(including compilation, assembly). Move relocation model Reloc::Model from
TargetMachine to MCCodeGenInfo so it's accessible even without TargetMachine.
llvm-svn: 135468
to MCRegisterInfo. Also initialize the mapping at construction time.
This patch eliminate TargetRegisterInfo from TargetAsmInfo. It's another step
towards fixing the layering violation.
llvm-svn: 135424
TargetAsmInfo, which in turn pulls in TargetRegisterInfo, etc. :-( There are
other cases of violations, but this is probably the worst.
This patch is but one small step towards fixing this. 500 more steps to go. :-(
llvm-svn: 135131
CPU, and feature string. Parsing some asm directives can change
subtarget state (e.g. .code 16) and it must be reflected in other
modules (e.g. MCCodeEmitter). That is, the MCSubtargetInfo instance
must be shared.
llvm-svn: 134795
- Each target asm parser now creates its own MCSubtatgetInfo (if needed).
- Changed AssemblerPredicate to take subtarget features which tablegen uses
to generate asm matcher subtarget feature queries. e.g.
"ModeThumb,FeatureThumb2" is translated to
"(Bits & ModeThumb) != 0 && (Bits & FeatureThumb2) != 0".
llvm-svn: 134678
be the first encoded as the first feature. It then uses the CPU name to look up
features / scheduling itineray even though clients know full well the CPU name
being used to query these properties.
The fix is to just have the clients explictly pass the CPU name!
llvm-svn: 134127
character in std::string was causing failures for a few ObjC and Obj-C++ tests
when -flto was enabled. Revision 133999 resolved this issue. Thanks Jay!
rdar://9685235
PR10210
llvm-svn: 134017
This was causing compile-time failures for some of the Objc and Obj-C++
benchmarks. The specific errors were of the form: "ld: duplicate symbol …"
rdar://9660124
llvm-svn: 133955
for all symbol differences and can drop the old EmitPCRelSymbolValue
method.
This also make getExprForFDESymbol on ELF equal to the one on MachO, and it
can be made non-virtual.
llvm-svn: 130634
functions and initializers, just report the declarations present in
the module.
The motivation is to open the way for using the lazy module parsing,
which should speed up clients that just want a symbol list (nm, ar).
This is slightly less precise, but since both -strip-dead-prototypes
and -globaldce are part of the standard pipeline, this shouldn't
change the result for clang/dragonegg produced binaries.
Any decl in an IL file was also put there because a FE expected it
to be necessary, so this should not be a problem for "-O0 -emit-llvm".
As a sanity check, I have bootstrapped clang on linux and built
firefox on both linux and darwin. A clang bootstrap on darwin
with LTO fails with or without this patch because, ironically,
the linker doesn't like the combination of dead_strip and LTO
when building libLTO.so :-)
llvm-svn: 127870
uses.
The result produced by the streamer is used to give the linker more accurate
information and to add to llvm.compiler.used. The second improvement removes
the need for the user to add __attribute__((used)) to functions only used in
inline asm. The first one lets us build firefox with LTO on Darwin :-)
llvm-svn: 126830
of a base class.
This makes it possible to unregister the file from FilesToRemove when
the file is done. Also, this eliminates the need for
formatted_tool_output_file.
llvm-svn: 112706
