AMDGPU sometimes has legal s16 and <2 x s16> operations, but all
registers are really 32-bit. An unmerge destination really should ben
widened to a 32-bit register. If widening a scalarizing vector with a
target size that matches the vector size, bitcast to integer and
extract the relevant bits with shifts.
I'm not sure if this is the right place for this. This could arguably
be part of widenScalar for the result. I also have a growing feeling
that we're missing a bitcast legalize action.
llvm-svn: 367604
Summary:
This will make it possible to improve IPRA by taking into account
register usage in indirect calls.
NFC yet; this is just laying the groundwork to start building
up patches to take advantage of the information for improved register
allocation.
Reviewers: aditya_nandakumar, volkan, qcolombet, arsenm, rovka, aemerson, paquette
Subscribers: sdardis, wdng, javed.absar, hiraditya, jrtc27, atanasyan, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65488
llvm-svn: 367476
This introduces a new family of combiner helper routines that re-use the
target specific cost model from SelectionDAG, and generate inline implementations
of the memcpy family of intrinsics.
The combines are only enabled at optimization levels higher than -O0, and give
very substantial performance improvements.
Differential Revision: https://reviews.llvm.org/D65167
llvm-svn: 366951
r366317 added a legalization for s128 G_ICMP narrow scalar which tried to hard
code the result type of the new legalized G_SELECT. Change this to instead use
type of the original G_ICMP result and allow the target to legalize it if necessary
later.
llvm-svn: 366943
I plan on adding memcpy optimizations in the GlobalISel pipeline, but we can't
do that unless we delay lowering to actual function calls. This patch changes
the translator to generate G_INTRINSIC_W_SIDE_EFFECTS for these functions, and
then have each target specify that using the new custom legalizer for intrinsics
hook that they want it expanded it a libcall.
Differential Revision: https://reviews.llvm.org/D64895
llvm-svn: 366516
Extract the sources to the GCD of the original size and target size,
padding with implicit_def as necessary.
Also fix the case where the requested source type is wider than the
original result type. This was ignoring the type, and just using the
destination. Do the operation in the requested type and truncate back.
llvm-svn: 366367
Use an anyext to the requested type for the leftover operand to
produce a slightly wider type, and then truncate the final merge.
I have another implementation almost ready which handles arbitrary
widens, but I think it produces worse code in this example (which I
think is 90% due to not folding redundant copies or folding out
implicit_def users), so I wanted to add this as a baseline first.
llvm-svn: 366366
Add narrowScalar to half of original size for G_ICMP.
ClampScalar G_ICMP's operands 2 and 3 to to s32.
Select G_ICMP for pointers for MIPS32. Pointer compare is same
as for integers, it is enough to declare them as legal type.
Differential Revision: https://reviews.llvm.org/D64856
llvm-svn: 366317
AMDGPU needs to allocate special argument registers separately from
the user function argument list, so needs direct control over the
CCState.
The ArgLocs argument is only really necessary because CCState doesn't
allow access to it.
llvm-svn: 366279
Since we have distinct types for pointers and scalars, G_INTTOPTRs can sometimes
obstruct attempts to find constant source values. These usually come about when
try to do some kind of null pointer check. Teaching getConstantVRegValWithLookThrough
about this operation allows the CBZ/CBNZ optimization to catch more cases.
This change also improves the case where we can't find a constant source at all.
Previously we would emit a cmp, cset and tbnz for that. Now we try to just emit
a cmp and conditional branch, saving an instruction.
The cumulative code size improvement of this change plus D64354 is 5.5% geomean
on arm64 CTMark -O0.
Differential Revision: https://reviews.llvm.org/D64377
llvm-svn: 365690
In SelectionDAG AMDGPU treated these as legal, but this was mostly
because the bitcasts required for FP types were painful. Theoretically
the bitpattern should eventually match to bfi, so don't bother trying
to get the patterns to import.
llvm-svn: 365583
If we have an icmp->brcond->br sequence where the brcond just branches to the
next block jumping over the br, while the br takes the false edge, then we can
modify the conditional branch to jump to the br's target while inverting the
condition of the incoming icmp. This means we can eliminate the br as an
unconditional branch to the fallthrough block.
Differential Revision: https://reviews.llvm.org/D64354
llvm-svn: 365510
Select gprb or fprb when def/use register operand of G_PHI is
used/defined by either:
copy to/from physical register or
instruction with only one mapping available for that use/def operand.
Integer s64 phi is handled with narrowScalar when mapping is applied,
produced artifacts are combined away. Manually set gprb to all register
operands of instructions created during narrowScalar.
Differential Revision: https://reviews.llvm.org/D64351
llvm-svn: 365494
If the requested source type an be used as a merge source type, create
a merge of merges. This avoids creating large, illegal extensions and
bit-ops directly to the result type.
llvm-svn: 364841
https://reviews.llvm.org/D31359
Add a hook "legalizeInstrinsic" to allow backends to override this
and custom lower/legalize intrinsics.
llvm-svn: 364821
Fix stack-use-after-scope errors from r364512. One instance was already
fixed in r364611 - this patch simplifies that fix and addresses one more
instance of similar code.
Discussed in: https://reviews.llvm.org/D63905
llvm-svn: 364778
The new switch lowering code that tries to generate jump tables and range checks
were tested at -O0 on arm64, but on -O3 the generic switch lowering code goes to
town on trying to generate optimized lowerings, e.g. multiple jump tables, range
checks etc. This exposed bugs in the way PHI nodes are handled because the CFG
looks even stranger after all of this is done.
llvm-svn: 364613
This patch intends to fix ASAN stack-use-after-scope error.
This is at least a short-term fix to unbreak LLVM's mainline.
Differential Revision: https://reviews.llvm.org/D63905
llvm-svn: 364611
Remove the last use of packRegs from IRTranslator and delete
pack/unpackRegs. This introduces a fallback to DAGISel for intrinsics
with aggregate arguments, since we don't have a testcase for them so
it's hard to tell how we'd want to handle them.
Discussed in https://reviews.llvm.org/D63551
llvm-svn: 364514
Change the interface of CallLowering::lowerCall to accept several
virtual registers for each argument, instead of just one. This is a
follow-up to D46018.
CallLowering::lowerReturn was similarly refactored in D49660 and
lowerFormalArguments in D63549.
With this change, we no longer pack the virtual registers generated for
aggregates into one big lump before delegating to the target. Therefore,
the target can decide itself whether it wants to handle them as separate
pieces or use one big register.
ARM and AArch64 have been updated to use the passed in virtual registers
directly, which means we no longer need to generate so many
merge/extract instructions.
NFCI for AMDGPU, Mips and X86.
Differential Revision: https://reviews.llvm.org/D63551
llvm-svn: 364512
Change the interface of CallLowering::lowerCall to accept several
virtual registers for the call result, instead of just one. This is a
follow-up to D46018.
CallLowering::lowerReturn was similarly refactored in D49660 and
lowerFormalArguments in D63549.
With this change, we no longer pack the virtual registers generated for
aggregates into one big lump before delegating to the target. Therefore,
the target can decide itself whether it wants to handle them as separate
pieces or use one big register.
ARM and AArch64 have been updated to use the passed in virtual registers
directly, which means we no longer need to generate so many
merge/extract instructions.
NFCI for AMDGPU, Mips and X86.
Differential Revision: https://reviews.llvm.org/D63550
llvm-svn: 364511
Change the interface of CallLowering::lowerFormalArguments to accept
several virtual registers for each formal argument, instead of just one.
This is a follow-up to D46018.
CallLowering::lowerReturn was similarly refactored in D49660. lowerCall
will be refactored in the same way in follow-up patches.
With this change, we forward the virtual registers generated for
aggregates to CallLowering. Therefore, the target can decide itself
whether it wants to handle them as separate pieces or use one big
register. We also copy the pack/unpackRegs helpers to CallLowering to
facilitate this.
ARM and AArch64 have been updated to use the passed in virtual registers
directly, which means we no longer need to generate so many
merge/extract instructions.
AArch64 seems to have had a bug when lowering e.g. [1 x i8*], which was
put into a s64 instead of a p0. Added a test-case which illustrates the
problem more clearly (it crashes without this patch) and fixed the
existing test-case to expect p0.
AMDGPU has been updated to unpack into the virtual registers for
kernels. I think the other code paths fall back for aggregates, so this
should be NFC.
Mips doesn't support aggregates yet, so it's also NFC.
x86 seems to have code for dealing with aggregates, but I couldn't find
the tests for it, so I just added a fallback to DAGISel if we get more
than one virtual register for an argument.
Differential Revision: https://reviews.llvm.org/D63549
llvm-svn: 364510
Allow CallLowering::ArgInfo to contain more than one virtual register.
This is useful when passes split aggregates into several virtual
registers, but need to also provide information about the original type
to the call lowering. Used in follow-up patches.
Differential Revision: https://reviews.llvm.org/D63548
llvm-svn: 364509
Avoids using a plain unsigned for registers throughoug codegen.
Doesn't attempt to change every register use, just something a little
more than the set needed to build after changing the return type of
MachineOperand::getReg().
llvm-svn: 364191
GlobalISel/IRTranslator.cpp now references SelectionDAG/FunctionLoweringInfo.cpp.
This fixes a link error in -DBUILD_SHARED_LIBS=on builds:
ld.lld: error: undefined symbol: llvm::FunctionLoweringInfo::clear()
>>> referenced by IRTranslator.cpp:2198 (../lib/CodeGen/GlobalISel/IRTranslator.cpp:2198)
>>> lib/CodeGen/GlobalISel/CMakeFiles/LLVMGlobalISel.dir/IRTranslator.cpp.o:(llvm::IRTranslator::finalizeFunction())
llvm-svn: 364124
This change makes use of the newly refactored SwitchLoweringUtils code from
SelectionDAG to in order to generate jump tables and range checks where appropriate.
Much of this code is ported from SDAG with some modifications. We generate
G_JUMP_TABLE and G_BRJT instructions when JT opportunities are found. This means
that targets which previously relied on the naive one MBB per case stmt
translation will now start falling back until they add support for the new opcodes.
For range checks, we don't generate any previously unused operations. This
just recognizes contiguous ranges of case values and generates a single block per
range. Single case value blocks are just a special case of ranges so we get that
support almost for free.
There are still some optimizations missing that I haven't ported over, and
bit-tests are also unimplemented. This patch series is already complex enough.
Actual arm64 support for selection of jump tables is coming in a later patch.
Differential Revision: https://reviews.llvm.org/D63169
llvm-svn: 364085
G_INTTOPTR can prevent the localizer from moving G_CONSTANTs, but since it's
essentially a side effect free cast instruction we can remat both instructions.
This patch changes the localizer to enable localization of the chains by
iterating over the entry block instructions in reverse order. That way, uses will
localized first, and then the defs are free to be localized as well.
This also changes the previous SmallPtrSet of localized instructions to use a
SetVector instead. We're dealing with pointers and need deterministic iteration
order.
Overall, this change improves ARM64 -O0 CTMark code size by around 0.7% geomean.
Differential Revision: https://reviews.llvm.org/D63630
llvm-svn: 364001
Daniel Sanders