G_BITREVERSE is generated from llvm.bitreverse.<type> intrinsics,
clang genrates these intrinsics from __builtin_bitreverse32 and
__builtin_bitreverse64.
Add lower and narrowscalar for G_BITREVERSE.
Lower G_BITREVERSE on MIPS32.
Recommit notes:
Introduce temporary variables in order to make sure
instructions get inserted into MachineFunction in same order
regardless of compiler used to build llvm.
Differential Revision: https://reviews.llvm.org/D71363
G_BITREVERSE is generated from llvm.bitreverse.<type> intrinsics,
clang genrates these intrinsics from __builtin_bitreverse32 and
__builtin_bitreverse64.
Add lower and narrowscalar for G_BITREVERSE.
Lower G_BITREVERSE on MIPS32.
Differential Revision: https://reviews.llvm.org/D71363
G_BSWAP is generated from llvm.bswap.<type> intrinsics, clang genrates
these intrinsics from __builtin_bswap32 and __builtin_bswap64.
Add lower and narrowscalar for G_BSWAP.
Lower G_BSWAP on MIPS32, select G_BSWAP on MIPS32 revision 2 and later.
Differential Revision: https://reviews.llvm.org/D71362
https://reviews.llvm.org/D70922
This adds a hook to allow targets to define exactly what extension
operation should be performed for widening constants. This handles cases
like widening i1 true which would end up becoming -1 which affects code
quality during combines.
Additionally, in order to stay consistent with how DAG is promoting
constants, we now signextend for byte sized types and zero extend
otherwise (by default). Targets can of course override this if
necessary.
Summary:
G_GEP is rather poorly named. It's a simple pointer+scalar addition and
doesn't support any of the complexities of getelementptr. I therefore
propose that we rename it. There's a G_PTR_MASK so let's follow that
convention and go with G_PTR_ADD
Reviewers: volkan, aditya_nandakumar, bogner, rovka, arsenm
Subscribers: sdardis, jvesely, wdng, nhaehnle, hiraditya, jrtc27, atanasyan, arphaman, Petar.Avramovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69734
We need to propagate this information from the IR in order to be able to safely
do tail call optimizations on the intrinsics during legalization. Assuming
it's safe to do tail call opt without checking for the marker isn't safe because
the mem libcall may use allocas from the caller.
This adds an extra immediate operand to the end of the intrinsics and fixes the
legalizer to handle it.
Differential Revision: https://reviews.llvm.org/D68151
llvm-svn: 373140
We currently always set the HasCalls on MFI during translation and legalization if
we're handling a call or legalizing to a libcall. However, if that call is later
optimized to a tail call then we don't need the flag. The flag being set to true
causes frame lowering to always save and restore FP/LR, which adds unnecessary code.
This change does the same thing as SelectionDAG and ports over some code that scans
instructions after selection, using TargetInstrInfo to determine if target opcodes
are known calls.
Code size geomean improvements on CTMark:
-O0 : 0.1%
-Os : 0.3%
Differential Revision: https://reviews.llvm.org/D67868
llvm-svn: 372443
r371901 was overeager and widenScalarDst() and the like in the legalizer
attempt to increment the insert point given in order to add new instructions
after the currently legalizing inst. In cases where the insertion point is not
exactly the current instruction, then callers need to de-compensate for the
behaviour by decrementing the insertion iterator before calling them. It's not
a nice state of affairs, for now just undo the problematic parts of the change.
llvm-svn: 372050
For some reason we sometimes insert new instructions one instruction before
the first non-PHI when legalizing. This can result in having non-PHI
instructions before PHIs, which mean that PHI elimination doesn't catch them.
Differential Revision: https://reviews.llvm.org/D67570
llvm-svn: 371901
Because memory intrinsics are handled differently than other calls, we need to
check them for tail call eligiblity in the legalizer. This allows us to still
inline them when it's beneficial to do so, but also tail call when possible.
This adds simple tail calling support for when the intrinsic is followed by a
return.
It ports the attribute checks from `TargetLowering::isInTailCallPosition` into
a similarly-named function in LegalizerHelper.cpp. The target-specific
`isUsedByReturnOnly` hook is not ported here.
Update tailcall-mem-intrinsics.ll to show that GlobalISel can now tail call
memory intrinsics.
Update legalize-memcpy-et-al.mir to have a case where we don't tail call.
Differential Revision: https://reviews.llvm.org/D67566
llvm-svn: 371893
Unlike SelectionDAG, treat this as a normally legalizable operation.
In SelectionDAG this is supposed to only ever formed if it's legal,
but I've found that to be restricting. For AMDGPU this is contextually
legal depending on whether denormal flushing is allowed in the use
function.
Technically we currently treat the denormal mode as a subtarget
feature, so custom lowering could be avoided. However I consider this
to be a defect, and this should be contextually dependent on the
controllable rounding mode of the parent function.
llvm-svn: 371800
Similar to the issue with G_ZEXT that was fixed earlier, this is a quick
to fall back if the source type is not exactly half of the dest type.
Fixes the clang-cmake-aarch64-lld bot build.
llvm-svn: 370847
Now that we have the infrastructure to support s128 types as parameters
we can expand these to libcalls.
Differential Revision: https://reviews.llvm.org/D66185
llvm-svn: 370823
Add lower for G_FPTOUI. Algorithm is similar to the SDAG version
in TargetLowering::expandFP_TO_UINT.
Lower G_FPTOUI for MIPS32.
Differential Revision: https://reviews.llvm.org/D66929
llvm-svn: 370431
This change moves the actual stack pointer manipulation into the legalizer,
available to targets via lower(). The codegen is slightly different because
we're using explicit masks instead of G_PTRMASK, and using G_SUB rather than
adding a negative amount via G_GEP.
Differential Revision: https://reviews.llvm.org/D66678
llvm-svn: 370104
Main difference is in the way Hi for Long shift (HiL) is made.
G_LSHR fills HiL with zeros, while G_ASHR fills HiL with sign bit value.
Differential Revision: https://reviews.llvm.org/D66589
llvm-svn: 370064
Fix typos. Use Hi and Lo prefixes for Or instead of LHS and RHS
to match names of surrounding variables.
Differential Revision: https://reviews.llvm.org/D66587
llvm-svn: 370062
The x86 tests are now broken (in paticular add-scalar.ll now hits the
DAG fallback) due to not handling G_UADDO. The DAG x86 backend has a
custom lowering for this, so that will need to be implemented.
llvm-svn: 369673
This is necessary for handling <3 x s16> on AMDGPU, assuming this
should be handled as 2 separate legalization actions. The alternative
would be for fewerElementsVector to handle 3->2.
llvm-svn: 369547
Add NarrowScalar for G_TRUNC when NarrowTy is half the size of source.
NarrowScalar G_TRUNC to s32 for MIPS32.
Differential Revision: https://reviews.llvm.org/D66202
llvm-svn: 369509
Again, it's weird that these are allowed. Since lowering support was added in
r368709 we started crashing on compiling the neon intrinsics test in the test
suite. This fixes the lowering to fold the 1 elt src/mask case into copies.
llvm-svn: 369135
Summary:
Targets often have instructions that can sign-extend certain cases faster
than the equivalent shift-left/arithmetic-shift-right. Such cases can be
identified by matching a shift-left/shift-right pair but there are some
issues with this in the context of combines. For example, suppose you can
sign-extend 8-bit up to 32-bit with a target extend instruction.
%1:_(s32) = G_SHL %0:_(s32), i32 24 # (I've inlined the G_CONSTANT for brevity)
%2:_(s32) = G_ASHR %1:_(s32), i32 24
%3:_(s32) = G_ASHR %2:_(s32), i32 1
would reasonably combine to:
%1:_(s32) = G_SHL %0:_(s32), i32 24
%2:_(s32) = G_ASHR %1:_(s32), i32 25
which no longer matches the special case. If your shifts and extend are
equal cost, this would break even as a pair of shifts but if your shift is
more expensive than the extend then it's cheaper as:
%2:_(s32) = G_SEXT_INREG %0:_(s32), i32 8
%3:_(s32) = G_ASHR %2:_(s32), i32 1
It's possible to match the shift-pair in ISel and emit an extend and ashr.
However, this is far from the only way to break this shift pair and make
it hard to match the extends. Another example is that with the right
known-zeros, this:
%1:_(s32) = G_SHL %0:_(s32), i32 24
%2:_(s32) = G_ASHR %1:_(s32), i32 24
%3:_(s32) = G_MUL %2:_(s32), i32 2
can become:
%1:_(s32) = G_SHL %0:_(s32), i32 24
%2:_(s32) = G_ASHR %1:_(s32), i32 23
All upstream targets have been configured to lower it to the current
G_SHL,G_ASHR pair but will likely want to make it legal in some cases to
handle their faster cases.
To follow-up: Provide a way to legalize based on the constant. At the
moment, I'm thinking that the best way to achieve this is to provide the
MI in LegalityQuery but that opens the door to breaking core principles
of the legalizer (legality is not context sensitive). That said, it's
worth noting that looking at other instructions and acting on that
information doesn't violate this principle in itself. It's only a
violation if, at the end of legalization, a pass that checks legality
without being able to see the context would say an instruction might not be
legal. That's a fairly subtle distinction so to give a concrete example,
saying %2 in:
%1 = G_CONSTANT 16
%2 = G_SEXT_INREG %0, %1
is legal is in violation of that principle if the legality of %2 depends
on %1 being constant and/or being 16. However, legalizing to either:
%2 = G_SEXT_INREG %0, 16
or:
%1 = G_CONSTANT 16
%2:_(s32) = G_SHL %0, %1
%3:_(s32) = G_ASHR %2, %1
depending on whether %1 is constant and 16 does not violate that principle
since both outputs are genuinely legal.
Reviewers: bogner, aditya_nandakumar, volkan, aemerson, paquette, arsenm
Subscribers: sdardis, jvesely, wdng, nhaehnle, rovka, kristof.beyls, javed.absar, hiraditya, jrtc27, atanasyan, Petar.Avramovic, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61289
llvm-svn: 368487
I've now needed to add an extra parameter to this call twice recently. Not only
is the signature getting extremely unwieldy, but just updating all of the
callsites and implementations is a pain. Putting the parameters in a struct
sidesteps both issues.
llvm-svn: 368408
This is an old commit that exposed a bug in the GISel importer, which caused
non-truncating stores to be selected for truncating store patterns. Now that's
been fixed in r367737 this can go back in.
llvm-svn: 367739
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
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
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
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
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
This was ignoring the flag on fneg, and using the source instruction's
flags. Also fixes tests missing from r358702.
Note the expansion itself isn't correct without nnan, but that should
be fixed separately.
llvm-svn: 363637
This is ported from the custom AMDGPU DAG implementation. I think this
is a better default expansion than what the DAG currently uses, at
least if the target has CTLZ.
This implements the signed version in terms of the unsigned
conversion, which is implemented with bit operations. SelectionDAG has
several other implementations that should eventually be ported
depending on what instructions are legal.
llvm-svn: 361081
Add legalizer support for G_FNEARBYINT. It's the same as G_FCEIL etc.
Since the importer allows us to automatically select this after legalization,
also add tests for selection etc. Also update arm64-vfloatintrinsics.ll.
llvm-svn: 359204
Same patch as G_FCEIL etc.
Add the missing switch case in widenScalar, add G_INTRINSIC_TRUNC to the correct
rule in AArch64LegalizerInfo.cpp, and add a test.
llvm-svn: 359021
Exactly the same as G_FCEIL, G_FABS, etc.
Add tests for the fp16/nofp16 behaviour, update arm64-vfloatintrinsics, etc.
Differential Revision: https://reviews.llvm.org/D60895
llvm-svn: 358799
This instruction is legalized in the same way as G_FSIN, G_FCOS, G_FLOG10, etc.
Update legalize-pow.mir and arm64-vfloatintrinsics.ll to reflect the change.
Differential Revision: https://reviews.llvm.org/D60218
llvm-svn: 358764
Legalize things like i24 load/store by splitting them into smaller power of 2 operations.
This matches how SelectionDAG handles these operations.
Differential Revision: https://reviews.llvm.org/D59971
llvm-svn: 358613
Same as G_EXP. Add a test, and update legalizer-info-validation.mir and
f16-instructions.ll.
Differential Revision: https://reviews.llvm.org/D60165
llvm-svn: 357605
The control flow here cannot ever use the uninitialized value, but it's
too hard for the compiler to figure that out. Clang warns:
llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:2600:28: error: variable 'CarrySum' is used uninitialized whenever 'for' loop exits because its condition is false [-Werror,-Wsometimes-uninitialized]
for (unsigned i = 2; i < Factors.size(); ++i)
^~~~~~~~~~~~~~~~~~
llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:2604:26: note: uninitialized use occurs here
CarrySumPrevDstIdx = CarrySum;
^~~~~~~~
llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:2600:28: note: remove the condition if it is always true
for (unsigned i = 2; i < Factors.size(); ++i)
^~~~~~~~~~~~~~~~~~
llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:2583:22: note: initialize the variable 'CarrySum' to silence this warning
unsigned CarrySum;
^
= 0
llvm-svn: 355818
Narrow Scalar G_MUL for MIPS32.
Revisit NarrowScalar implementation in LegalizerHelper.
Introduce new helper function multiplyRegisters.
It performs generic multiplication of values held in multiple registers.
Generated instructions use only types NarrowTy and i1.
Destination can be same or two times size of the source.
Differential Revision: https://reviews.llvm.org/D58824
llvm-svn: 355814
Legalize/select llvm.ctlz.*
Add select-ctlz to show that we actually select them. Update arm64-clrsb.ll and
arm64-vclz.ll to show that we perform valid transformations in optimized builds,
and document where GISel can improve.
Differential Revision: https://reviews.llvm.org/D58155
llvm-svn: 354299
Select G_BR and G_BRCOND for MIPS32.
Unconditional branch G_BR does not have register operand,
for that reason we only add tests.
Since conditional branch G_BRCOND compares register to zero on MIPS32,
explicit extension must be performed on i1 condition in order to set
high bits to appropriate value.
Differential Revision: https://reviews.llvm.org/D58182
llvm-svn: 354022
This teaches the legalizer about G_FFLOOR, and lets us select G_FFLOOR in
AArch64.
It updates the existing floating point tests, and adds a select-floor.mir test.
Differential Revision: https://reviews.llvm.org/D57486
llvm-svn: 353722
Make behavior of G_LOAD in widenScalar same as for G_ZEXTLOAD and
G_SEXTLOAD. That is perform widenScalarDst to size given by the target
and avoid additional checks in common code. Targets can reorder or add
additional rules in LegalizeRuleSet for the opcode to achieve desired
behavior.
Select extending load that does not have specified type of extension
into zero extending load.
Select truncating store that stores number of bytes indicated by size
in MachineMemoperand.
Differential Revision: https://reviews.llvm.org/D57454
llvm-svn: 353520
This is pretty much directly ported from SelectionDAG. Doesn't include
the shift by non-constant but known bits version, since there isn't a
globalisel version of computeKnownBits yet.
This shows a disadvantage of targets not specifically which type
should be used for the shift amount. If type 0 is legalized before
type 1, the operations on the shift amount type use the wider type
(which are also less likely to legalize). This can be avoided by
targets specifying legalization actions on type 1 earlier than for
type 0.
llvm-svn: 353455
Introduce a new function which handles instructions with multiple type
indices, but have the same number of vector elements.
Also legalize v2s16 shifts when applicable.
llvm-svn: 353432
The fewerElementsVectors implementation for load/stores
handles the scalar reduction case just as well, so drop
the redundant code in narrowScalar. This also introduces
support for narrowing irregular size breakdowns for
scalars.
llvm-svn: 353125
Don't handle vector conditions.
I think this can be merged in the future with
fewerElementsVectorSelect, although this becomes slightly tricky with
a vector condition.
llvm-svn: 353122
For the scalar case only.
Also move the similar G_MERGE_VALUES handling to a separate function
and cleanup to make them look more similar.
llvm-svn: 352979
Also fix an alignment bug getMachineMemOperand. If the
tracked value is null, the offset isn't tracked so the
base alignment needs to be reduced.
llvm-svn: 352716
This teaches the legalizer to handle G_FEXP in AArch64. As a result, it also
allows us to select G_FEXP.
It...
- Updates the legalizer-info tests
- Adds a test for legalizing exp
- Updates the existing fp tests to show that we can now select G_FEXP
https://reviews.llvm.org/D57483
llvm-svn: 352692
This teaches GlobalISel to emit a RTLib call for @llvm.log2 when it encounters
it.
It updates the existing floating point tests to show that we don't fall back on
the intrinsic, and select the correct instructions. It also adds a legalizer
test for G_FLOG2.
https://reviews.llvm.org/D57357
llvm-svn: 352673
This teaches the legalizer about G_FSQRT in AArch64. Also adds a legalizer
test for G_FSQRT, a selection test for it, and updates existing floating point
tests.
https://reviews.llvm.org/D57361
llvm-svn: 352671
This was ignoring the memory size, and producing multiple loads/stores
if the operand size was different from the memory size.
I assume this is the intent of not having an explicit G_ANYEXTLOAD
(although I think that would probably be better).
llvm-svn: 352523
This adds support for legalizing G_FLOG into a RTLib call.
It adds a legalizer test, and updates the existing floating point tests.
https://reviews.llvm.org/D57347
llvm-svn: 352429
This adds instruction selection support for @llvm.log10 in AArch64. It teaches
GISel to lower it to a library call, updates the relevant tests, and adds a
legalizer test for log10.
https://reviews.llvm.org/D57341
llvm-svn: 352418
This contains all of the legalizer changes from D57197 necessary to select
G_FCOS and G_FSIN. It also updates several existing IR tests in
test/CodeGen/AArch64 that verify that we correctly lower the G_FCOS and G_FSIN
instructions.
https://reviews.llvm.org/D57197
3/3
llvm-svn: 352402
Lower G_USUBO and G_USUBE. Add narrowScalar for G_SUB.
Legalize and select G_SUB for MIPS 32.
Differential Revision: https://reviews.llvm.org/D53416
llvm-svn: 352351
Matt Arsenault