Summary:
The linker needs to be able to determine whether a symbol is text or data to
handle the case of a common being overridden by a strong definition in an
archive. If the archive contains a text member of the same name as the common,
that function is discarded. However, if the archive contains a data member of
the same name, that strong definition overrides the common. This is a behavior
of ld.bfd, which the Qualcomm linker also supports in LTO.
Here's a test case to illustrate:
####
cat > 1.c << \!
int blah;
!
cat > 2.c << \!
int blah() {
return 0;
}
!
cat > 3.c << \!
int blah = 20;
!
clang -c 1.c
clang -c 2.c
clang -c 3.c
ar cr lib.a 2.o 3.o
ld 1.o lib.a -t
####
The correct output is:
1.o
(lib.a)3.o
Thanks to Shankar Easwaran and Hemant Kulkarni for the test case!
Reviewers: mehdi_amini, rafael, pcc, davide
Reviewed By: pcc
Subscribers: davide, llvm-commits, inglorion
Differential Revision: https://reviews.llvm.org/D31901
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300205 91177308-0d34-0410-b5e6-96231b3b80d8
Instructions CALLSEQ_START..CALLSEQ_END and their target dependent
counterparts keep data like frame size, stack adjustment etc. These
data are accessed by getOperand using hard coded indices. It is
error prone way. This change implements the access by special methods,
which improve readability and allow changing data representation without
massive changes of index values.
Differential Revision: https://reviews.llvm.org/D31953
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300196 91177308-0d34-0410-b5e6-96231b3b80d8
Throughout the effort of automatically generating the X86 memory folding tables these missing information were encountered.
This is a preparation work for a future patch including the automation of these tables.
Differential Revision: https://reviews.llvm.org/D31714
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300190 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
APInt is currently implemented with an unsigned BitWidth field first and then a uint_64/pointer union. Due to the 64-bit size of the union there is a hole after the bitwidth.
Putting the union first allows the class to be packed. Making it 12 bytes instead of 16 bytes. An APSInt goes from 20 bytes to 16 bytes.
This shows a 4k reduction on the size of the opt binary on my local x86-64 build. So this enables some other improvement to the code as well.
Reviewers: dblaikie, RKSimon, hans, davide
Reviewed By: davide
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D32001
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300171 91177308-0d34-0410-b5e6-96231b3b80d8
This patch allows Error and Expected types to be passed to and returned from
RPC functions.
Serializers and deserializers for custom error types (types deriving from the
ErrorInfo class template) can be registered with the SerializationTraits for
a given channel type (see registerStringError in RPCSerialization.h for an
example), allowing a given custom type to be sent/received. Unregistered types
will be serialized/deserialized as StringErrors using the custom type's log
message as the error string.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300167 91177308-0d34-0410-b5e6-96231b3b80d8
This is a magic header file supported by the build system that provides a
single definition, LLVM_REVISION, containing an LLVM revision identifier,
if available. This functionality previously lived in the LTO library, but
I am moving it out to lib/Support because I want to also start using it in
lib/Object to create the IR symbol table.
This change also fixes a bug where LLVM_REVISION was never actually being
used in lib/LTO because the macro HAS_LLVM_REVISION was never defined (it
was misspelled as HAVE_SVN_VERSION_INC in lib/LTO/CMakeLists.txt, and was
only being defined in a non-existent file Version.cpp).
I also changed the code to use "git rev-parse --git-dir" to locate the .git
directory, instead of looking for it in the LLVM source root directory,
which makes this compatible with monorepos as well as git worktrees.
Differential Revision: https://reviews.llvm.org/D31985
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300160 91177308-0d34-0410-b5e6-96231b3b80d8
This seems like a much more natural API, based on Derek Schuff's
comments on r300015. It further hides the implementation detail of
AttributeList that function attributes come last and appear at index
~0U, which is easy for the user to screw up. git diff says it saves code
as well: 97 insertions(+), 137 deletions(-)
This also makes it easier to change the implementation, which I want to
do next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300153 91177308-0d34-0410-b5e6-96231b3b80d8
This typedef used to be conditional based on whether rvalue references were supported. Looks like it got left behind when we switched to always having rvalue references with c++11. I don't think it provides any value now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300146 91177308-0d34-0410-b5e6-96231b3b80d8
Improve performance of argument list parsing with large numbers of IDs and
large numbers of arguments, by tracking a conservative range of indexes within
the argument list that might contain an argument with each ID. In the worst
case (when the first and last argument with a given ID are at the opposite ends
of the argument list), this still results in a linear-time walk of the list,
but it helps substantially in the common case where each ID occurs only once,
or a few times close together in the list.
This gives a ~10x speedup to clang's `test/Driver/response-file.c`, which
constructs a very large set of command line arguments and feeds them to the
clang driver.
Differential Revision: https://reviews.llvm.org/D30130
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300135 91177308-0d34-0410-b5e6-96231b3b80d8
In a followup patch I intend to introduce an additional dumping
mode which dumps a graphical representation of a class's layout.
In preparation for this, the text-based layout printer needs to
be split out from the graphical layout printer, and both need
to be able to use the same code for printing the intro and outro
of a class's definition (e.g. base class list, etc).
This patch does so, and in the process introduces a skeleton
definition for the graphical printer, while currently making
the graphical printer just print nothing.
NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300134 91177308-0d34-0410-b5e6-96231b3b80d8
Previously the dumping of class definitions was very primitive,
and it made it hard to do more than the most trivial of output
formats when dumping. As such, we would only dump one line for
each field, and then dump non-layout items like nested types
and enums.
With this patch, we do a complete analysis of the object
hierarchy including aggregate types, bases, virtual bases,
vftable analysis, etc. The only immediately visible effects
of this are that a) we can now dump a line for the vfptr where
before we would treat that as padding, and b) we now don't
treat virtual bases that come at the end of a class as padding
since we have a more detailed analysis of the class's storage
usage.
In subsequent patches, we should be able to use this analysis
to display a complete graphical view of a class's layout including
recursing arbitrarily deep into an object's base class / aggregate
member hierarchy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300133 91177308-0d34-0410-b5e6-96231b3b80d8
The test fails on Darwin because Fuzzer::DeathCallback (which calls
DumpCurrentUnit("crash-")) is called before DumpCurrentUnit("oom-") is
called in Fuzzer::RssLimitCallback. DeathCallback is transitively called
from __sanitizer_print_memory_profile.
This should fix the fuzzer bot that has been failing for a while:
http://lab.llvm.org:8080/green/job/libFuzzer/
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300127 91177308-0d34-0410-b5e6-96231b3b80d8
Previously it tried to call SimplifyInstruction which doesn't know anything about alloca so defers to constant folding which also doesn't do anything with alloca. This results in wasted cycles making calls that won't do anything. Given the frequency with which this function is called this time adds up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300118 91177308-0d34-0410-b5e6-96231b3b80d8
This replicates the known bits and constant creation code from the single use case for these instructions and adds it here. The computeKnownBits and constant creation code for other instructions is now in the default case of the opcode switch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300094 91177308-0d34-0410-b5e6-96231b3b80d8
We already handled a superset check that included the known ones too and folded to a constant that may include ones. But it can also handle the case of no ones.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300093 91177308-0d34-0410-b5e6-96231b3b80d8
The use of a DenseMap in precomputeTriangleChains does not cause
non-determinism, even though it is iterated over, as the only thing the
iteration does is to insert entries into a new DenseMap, which is not iterated.
Comment only change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300088 91177308-0d34-0410-b5e6-96231b3b80d8
Currently if we reach an instruction with multiples uses we know we can't do any optimizations to that instruction itself since we only have the demanded bits for one of the users. But if we know all of the bits are zero/one for that one user we can still go ahead and create a constant to give to that user.
This might then reduce the instruction to having a single use and allow additional optimizations on the other path.
This picks up an additional case that r300075 didn't catch.
Differential Revision: https://reviews.llvm.org/D31552
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300084 91177308-0d34-0410-b5e6-96231b3b80d8
The current heuristic is triggered on `InFlightCount > BufferLimit`
which isn't really helpful on in-order cores where BufferLimit is zero.
Note that we already get latency hiding effects for in order cores
by instructions staying in the pending queue on stalls; The additional
latency scheduling heuristics only have minimal effects after that while
occasionally increasing register pressure too much resulting in extra
spills.
My motivation here is additional spills/reloads ending up in a loop in
464.h264ref / BlockMotionSearch function resulting in a 4% overal
regression on an in order core. rdar://30264380
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300083 91177308-0d34-0410-b5e6-96231b3b80d8
If we are adding/subtractings 0s below the highest demanded bit we can just use the other operand and remove the operation.
My primary motivation is observing that we can call ShrinkDemandedConstant for the add/sub and create a 0 constant, rather than removing the add completely. In the case I saw, we modified the constant on an add instruction to a 0, but the add is not put into the worklist. So we didn't revisit it until the next InstCombine iteration. This caused an IR modification to remove add and a subsequent iteration to be ran.
With this change we get bypass the add in the first iteration and prevent the second iteration from changing anything.
Differential Revision: https://reviews.llvm.org/D31120
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300075 91177308-0d34-0410-b5e6-96231b3b80d8
One potential way to make InstCombine (very slightly?) faster is to recycle instructions
when possible instead of creating new ones. It's not explicitly stated AFAIK, but we don't
consider this an "InstSimplify". We could, however, make a new layer to house transforms
like this if that makes InstCombine more manageable (just throwing out an idea; not sure
how much opportunity is actually here).
Differential Revision: https://reviews.llvm.org/D31863
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300067 91177308-0d34-0410-b5e6-96231b3b80d8
