routines and fix all of the bugs they expose.
I hit a test case that crashed even without these asserts due to passing
a non-exiting latch to the ExitingBlock parameter of the trip count
computation machinery. However, when I add the nice asserts, it turns
out we have plenty of coverage of these bugs, they just didn't manifest
in crashers.
The core problem seems to stem from an assumption that the latch *is*
the exiting block. While this is often true, and somewhat the "normal"
way to think about loops, it isn't necessarily true. The correct way to
call the trip count routines in a *generic* fashion (that is, without
a particular exit in mind) is to just use the loop's single exiting
block if it has one. The trip count can't be computed generically unless
it does. This works great for the loop vectorizer. The loop unroller
actually *wants* to select the latch when it has to chose between
multiple exits because for unrolling it is the latch trips that matter.
But if this is the desire, it needs to explicitly guard for non-exiting
latches and check for the generic trip count in that case.
I've added the asserts, and added convenience APIs for querying the trip
count generically that check for a single exit block. I've kept the APIs
consistent between computing trip count and trip multiples.
Thansk to Mark for the help debugging and tracking down the *right* fix
here!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219550 91177308-0d34-0410-b5e6-96231b3b80d8
In fact, symbolization is now expected to work only on Linux and
FreeBSD/NetBSD, where we have dl_iterate_phdr and can learn the
main executable name without argv0 (it will be possible on BSD systems
after http://reviews.llvm.org/D5693 lands). #ifdef-out the code for
all the rest Unix systems.
Reviewed in http://reviews.llvm.org/D5610
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219534 91177308-0d34-0410-b5e6-96231b3b80d8
ScalarEvolution in the presence of multiple exits. Previously all
loops exits had to have identical counts for a loop trip count to be
considered computable. This pessimization was implemented by calling
getBackedgeTakenCount(L) rather than getExitCount(L, ExitingBlock)
inside of ScalarEvolution::getSmallConstantTripCount() (see the FIXME
in the comments of that function). The pessimization was added to fix
a corner case involving undefined behavior (pr/16130). This patch more
precisely handles the undefined behavior case allowing the pessimization
to be removed.
ControlsExit replaces IsSubExpr to more precisely track the case where
undefined behavior is expected to occur. Because undefined behavior is
tracked more precisely we can remove MustExit from ExitLimit. MustExit
was used to track the case where the limit was computed potentially
assuming undefined behavior even if undefined behavior didn't necessarily
occur.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219517 91177308-0d34-0410-b5e6-96231b3b80d8
DW_AT_specification and DW_AT_abstract_origin resolving was only performed
on subroutine DIEs because it used the getSubroutineName method. Introduce
a more generic getName() and use it to dump the reference attributes.
Testcases have been updated to check the printed names instead of the offsets
except when the name could be ambiguous.
Reviewers: dblaikie, samsonov
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5625
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219506 91177308-0d34-0410-b5e6-96231b3b80d8
We, I suppose naïvely, believed the COFF specification with regard to
auxiliary symbol records which defined sections: they specified that the
symbol value should be zero. However, dumpbin and MinGW's objdump do
not consider the symbol value as a restriction. Relaxing this allows us
to properly dump MinGW linked executables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219479 91177308-0d34-0410-b5e6-96231b3b80d8
to what we actually want ilogb implementation. This makes everything
*much* easier to deal with and is actually what we want when using it
anyways.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219474 91177308-0d34-0410-b5e6-96231b3b80d8
code using it more readable.
Also add a copySign static function that works more like the standard
function by accepting the value and sign-carying value as arguments.
No interesting logic here, but tests added to cover the basic API
additions and make sure they do something plausible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219453 91177308-0d34-0410-b5e6-96231b3b80d8
This patch removes the PBQPBuilder class and its subclasses and replaces them
with a composable constraints class: PBQPRAConstraint. This allows constraints
that are only required for optimisation (e.g. coalescing, soft pairing) to be
mixed and matched.
This patch also introduces support for target writers to supply custom
constraints for their targets by overriding a TargetSubtargetInfo method:
std::unique_ptr<PBQPRAConstraints> getCustomPBQPConstraints() const;
This patch should have no effect on allocations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219421 91177308-0d34-0410-b5e6-96231b3b80d8
While getSectionContents was updated to do the right thing,
getSectionSize wasn't. Move the logic to getSectionSize and leverage it
from getSectionContents.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219391 91177308-0d34-0410-b5e6-96231b3b80d8
This adds the Pat<>'s for the intrinsics. These are necessary because we
don't lower these intrinsics to SDNodes but match them directly. See the
rational in the previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219362 91177308-0d34-0410-b5e6-96231b3b80d8
This change modifies fatal signal handler used in LLVM tools.
Now it attempts to find llvm-symbolizer binary and communicates
with it in order to turn instruction addresses into
function/file/line info entries. This should significantly improve
stack traces readability in Debug builds.
This feature only works on selected platforms (including Darwin
and Linux). If the symbolization fails for some reason, signal
handler will fallback to the original behavior.
Reviewed in http://reviews.llvm.org/D5610
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219354 91177308-0d34-0410-b5e6-96231b3b80d8
One of many steps to generalize subprogram emission to both the DWO and
non-DWO sections (to emit -gmlt-like data under fission). Once the
functions are pushed down into DwarfCompileUnit some of the data
structures will be pushed at least into DwarfFile so that they can be
unique per-file, allowing emission to both files independently.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219345 91177308-0d34-0410-b5e6-96231b3b80d8
There are two methods in SectionRef that can fail:
* getName: The index into the string table can be invalid.
* getContents: The section might point to invalid contents.
Every other method will always succeed and returning and std::error_code just
complicates the code. For example, a section can have an invalid alignment,
but if we are able to get to the section structure at all and create a
SectionRef, we will always be able to read that invalid alignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219314 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We currently emit an DW_AT_APPLE_property_attribute with a value that is a
bitfield describing the various attributes applied to an ObjectiveC property.
While trying to add testing to one of my dwarfdump patches that would pretty
print that, I realized this information looks totally broken and has maybe
never been correct.
As with every DWARF info, we have some enum in Dwarf.h that describes this
attribute (enum ApplePropertyAttributes). It seems however that the attribute
value is set from another definition of these flags in Sema/DeclSpec.h (enum
ObjCPropertyAttributeKind). And these 2 enums aren't in sync.
This patch updates the Dwarf.h values to the ones we are (and have been for
a very long time) emitting. We change some publicly (and even documented
in SourceLevelDebugging.rst) values, but I doubt this could be an issue as
the information has been wrong for so long...
Reviewers: echristo, dblaikie, aprantl
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5653
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219311 91177308-0d34-0410-b5e6-96231b3b80d8
After 4 years there is still no normalization library. We do support
disassembly and relocations, so it doesn't look like we need it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219308 91177308-0d34-0410-b5e6-96231b3b80d8
DWARF in COFF utilizes several relocations. Implement support for them
in RelocVisitor to support llvm-dwarfdump.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219280 91177308-0d34-0410-b5e6-96231b3b80d8
propagate. Also use the TargetSubtargetInfo and the MachineFunction
and move TargetRegisterInfo query closer to uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219273 91177308-0d34-0410-b5e6-96231b3b80d8
mach-o supports "fat" files which are a header/table-of-contents followed by a
concatenation of mach-o files built for different architectures. Currently,
MemoryBuffer has no easy way to map a subrange (slice) of a file which lld
will need to select a mach-o slice of a fat file. The new function provides
an easy way to map a slice of a file into a MemoryBuffer. Test case included.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219260 91177308-0d34-0410-b5e6-96231b3b80d8
getOpenFileSlice gets passed the map size, so it makes no sense to say that
the size is volatile. The code will not even compute the size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219226 91177308-0d34-0410-b5e6-96231b3b80d8
On this file we had a mix of
* Twine
* const char *
* StringRef
The two that make sense are
* const Twine & (caller convenience)
* consc char * (that is what will eventually be passed to open.
Given that sys::fs::openFileForRead takes a "const Twine &", I picked that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219224 91177308-0d34-0410-b5e6-96231b3b80d8
Most Unix-like operating systems guarantee that the file descriptor is
closed after a call to close(2), even if close comes back with EINTR.
For these systems, calling close _again_ will either do nothing or close
some other file descriptor open(2)'d by another thread. (Linux)
However, some operating systems do not have this behavior. They require
at least another call to close(2) before guaranteeing that the
descriptor is closed. (HP-UX)
And some operating systems have an unpredictable blend of the two
behaviors! (xnu)
Avoid this disaster by blocking all signals before we call close(2).
This ensures that a signal will not be delivered to the thread and
close(2) will not give us back EINTR. We restore the signal mask once
the operation is done.
N.B. This isn't a problem on Windows, it doesn't have a notion of EINTR
because signals always get delivered to dedicated signal handling
threads.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219189 91177308-0d34-0410-b5e6-96231b3b80d8
It's possible to start a program with one (or all) of the standard file
descriptors closed. Subsequent open system calls will give the program
a low-numbered file descriptor.
This is problematic because we may believe we are writing to standard
out instead of a file.
Introduce Process::FixupStandardFileDescriptors, a helper function to
remap standard file descriptors to /dev/null if they were closed before
the program started.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219170 91177308-0d34-0410-b5e6-96231b3b80d8
The patch's author points out that, despite the function's documentation,
getSetCCResultType is only used to get the SETCC result type (with one
here-removed problematic exception). In one case, getSetCCResultType was being
used to get the predicate type to use for a SELECT node, and then
SIGN_EXTENDing (or truncating) to get the input predicate to match that type.
Unfortunately, this was happening inside visitSIGN_EXTEND, and creating new
SIGN_EXTEND nodes was causing an infinite loop. In addition, this behavior was
wrong if a target was not using ZeroOrNegativeOneBooleanContent. Lastly, the
extension/truncation seems unnecessary here: SELECT is defined as:
Select(COND, TRUEVAL, FALSEVAL). If the type of the boolean COND is not i1
then the high bits must conform to getBooleanContents.
So here we remove this use of getSetCCResultType and update
getSetCCResultType's documentation to reflect its actual uses.
Patch by deadal nix!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219141 91177308-0d34-0410-b5e6-96231b3b80d8
output of the llvm-dwarfdump and llvm-objdump report the endianness
used when the object files were generated.
Patch by Charlie Turner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219110 91177308-0d34-0410-b5e6-96231b3b80d8
