Summary:
If the ExtractElement instructions can be optimized out during the
vectorization and we need to reshuffle the parent vector, this
ShuffleInstruction may be inserted in the wrong place causing compiler
to produce incorrect code.
Reviewers: spatel, RKSimon, mkuper, hfinkel, javed.absar
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D49928
llvm-svn: 338380
We could choose a free 0 for this, but this
matches the behavior for fmul undef, 1.0. Also,
the NaN use is more useful for folding use operations
although if it's not eliminated it is more expensive
in terms of code size.
llvm-svn: 338376
The LLD implementation of Tag_ABI_VFP_args needs to check the rarely seen
values of 3 (toolchain specific) and 4 compatible with both Base and VFP.
Add the missing enumeration values so that LLD can refer to them without
having to use the raw numbers.
Differential Revision: https://reviews.llvm.org/D50049
llvm-svn: 338373
This patch teaches llvm-mca how to identify dependency breaking instructions on
btver2.
An example of dependency breaking instructions is the zero-idiom XOR (example:
`XOR %eax, %eax`), which always generates zero regardless of the actual value of
the input register operands.
Dependency breaking instructions don't have to wait on their input register
operands before executing. This is because the computation is not dependent on
the inputs.
Not all dependency breaking idioms are also zero-latency instructions. For
example, `CMPEQ %xmm1, %xmm1` is independent on
the value of XMM1, and it generates a vector of all-ones.
That instruction is not eliminated at register renaming stage, and its opcode is
issued to a pipeline for execution. So, the latency is not zero.
This patch adds a new method named isDependencyBreaking() to the MCInstrAnalysis
interface. That method takes as input an instruction (i.e. MCInst) and a
MCSubtargetInfo.
The default implementation of isDependencyBreaking() conservatively returns
false for all instructions. Targets may override the default behavior for
specific CPUs, and return a value which better matches the subtarget behavior.
In future, we should teach to Tablegen how to automatically generate the body of
isDependencyBreaking from scheduling predicate definitions. This would allow us
to expose the knowledge about dependency breaking instructions to the machine
schedulers (and, potentially, other codegen passes).
Differential Revision: https://reviews.llvm.org/D49310
llvm-svn: 338372
The ELF for the Arm architecture document defines, for EF_ARM_EABI_VER5 and
above, the flags EF_ARM_ABI_FLOAT_HARD and EF_ARM_ABI_FLOAT_SOFT. These
have been defined to be compatible with the existing EF_ARM_VFP_FLOAT and
EF_ARM_SOFT_FLOAT used by gcc for EF_ARM_EABI_UNKNOWN.
This patch adds the flags in addition to the existing ones so that any code
depending on the old names will still work.
Differential Revision: https://reviews.llvm.org/D49992
llvm-svn: 338370
Since z13, the max group size will be 2 if any μop has more than 3 register
sources.
This has been ignored sofar in the SystemZHazardRecognizer, but is now
handled by recognizing those instructions and adjusting the tracking of
decoding and the cost heuristic for grouping.
Review: Ulrich Weigand
https://reviews.llvm.org/D49847
llvm-svn: 338368
This fold was written in an odd way and tried to avoid
an endless loop by bailing out on all constants instead
of the supposedly problematic case of -1. But (X & -1)
should always be simplified before we reach here, so I'm
not sure how that is a problem.
There were no tests for the commuted patterns, so I added
those at rL338364.
llvm-svn: 338367
isFNEG was duplicating much of what was done by getTargetConstantBitsFromNode in its own calls to getTargetConstantFromNode.
Noticed while reviewing D48467.
llvm-svn: 338358
Contrary to ELF, we don't add any markers that distinguish data generated
with .short/.long from normal instructions, so the .inst directive only
adds compatibility with assembly that uses it.
Differential Revision: https://reviews.llvm.org/D49936
llvm-svn: 338356
Contrary to ELF, we don't add any markers that distinguish data generated
with .long from normal instructions, so the .inst directive only adds
compatibility with assembly that uses it.
Differential Revision: https://reviews.llvm.org/D49935
llvm-svn: 338355
The patch introduces loop analysis (VPLoopInfo/VPLoop) for VPBlockBases.
This analysis will be necessary to perform some H-CFG transformations and
detect and introduce regions representing a loop in the H-CFG.
Reviewers: fhahn, rengolin, mkuper, hfinkel, mssimpso
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D48816
llvm-svn: 338346
In one place we checked X86Subtarget.slowLEA() to decide if the pass should run. But to decide what the pass should we only check isSLM. This resulted in Goldmont going down the Bonnell path.
llvm-svn: 338342
This patch fixes demangling of template aliases as template-template
arguments, and also fixes function pointers and references as
not type template parameters. All of these can be properly
demangled now, so I've ported over the test
clang/test/CodeGenCXX/ms-template-callbacks.cpp. All of these
tests pass
llvm-svn: 338340
Also refactors some existing code to materialize addresses for the large code
model so it can be shared between G_GLOBAL_VALUE and G_BLOCK_ADDR.
This implements PR36390.
Differential Revision: https://reviews.llvm.org/D49903
llvm-svn: 338337
The vector contains the SDNodes that these functions create. The number of nodes is always a small number so we should use SmallVector to avoid a heap allocation.
llvm-svn: 338329
This patch adds support for demangling r-value references, new
operators such as the ""_foo operator, lambdas, alias types,
nullptr_t, and various other C++11'isms.
There is 1 failing test remaining in this file, which appears to
be related to back-referencing. This type of problem has the
potential to get ugly so I'd rather fix it in a separate patch.
Differential Revision: https://reviews.llvm.org/D50013
llvm-svn: 338324
Summary:
This patch mostly copies the existing Instruction Flow, and stage descriptions
from the mca README. I made a few text tweaks, but no semantic changes,
and made reference to the "default pipeline." I also removed the internals
references (e.g., reference to class names and header files). I did leave the
LSUnit name around, but only as an abbreviated word for the load-store unit.
Reviewers: andreadb, courbet, RKSimon, gbedwell, filcab
Reviewed By: andreadb
Subscribers: tschuett, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D49692
llvm-svn: 338319
This is exchanging a sub-of-1 with add-of-minus-1:
https://rise4fun.com/Alive/plKAH
This is another step towards improving select-of-constants codegen (see D48970).
x86 is the motivating target, and those diffs all appear to be wins. PPC and AArch64 look neutral.
I've limited this to early combining (!LegalOperations) in case a target wants to reverse it, but
I think canonicalizing to 'add' is more likely to produce further transforms because we have more
folds for 'add'.
Differential Revision: https://reviews.llvm.org/D49924
llvm-svn: 338317
The patch introduces dominator analysis for VPBlockBases and extend
VPlan's GraphTraits specialization with the required interfaces. Dominator
analysis will be necessary to perform some H-CFG transformations and
to introduce VPLoopInfo (LoopInfo analysis on top of the VPlan representation).
Reviewers: fhahn, rengolin, mkuper, hfinkel, mssimpso
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D48815
llvm-svn: 338310
Also, make SerializationTraits for pairs forward the actual pair
template type arguments to the underlying serializer. This allows, for example,
std::pair<StringRef, bool> to be passed as an argument to an RPC call expecting
a std::pair<std::string, bool>, since there is an underlying serializer from
StringRef to std::string that can be used.
llvm-svn: 338305
Thinking about it more it might be possible for the later nodes to be folded in getNode in such a way that the other created nodes are left dead. This can cause use counts to be incorrect on nodes that aren't dead.
So its probably safer to leave this alone.
llvm-svn: 338298
Summary:
Normally, inling does not happen if caller does not have
"null-pointer-is-valid"="true" attibute but callee has it.
However, alwaysinline may force callee to be inlined.
In this case, if the caller has the "null-pointer-is-valid"="true"
attribute, copy the attribute to caller.
Reviewers: efriedma, a.elovikov, lebedev.ri, jyknight
Reviewed By: efriedma
Subscribers: eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D50000
llvm-svn: 338292
This teaches the outliner to save LR to a register rather than the stack when
possible. This allows us to avoid bumping the stack in outlined functions in
some cases. By doing this, in a later patch, we can teach the outliner to do
something like this:
f1:
...
bl OUTLINED_FUNCTION
...
f2:
...
move LR's contents to a register
bl OUTLINED_FUNCTION
move the register's contents back
instead of falling back to saving LR in both cases.
llvm-svn: 338278
