Cannon Lake does not support CLWB, therefore it
does not include all features listed under SKX anymore.
Instead, enumerate all SKX features with the exception of CLWB.
Patch by Gabor Buella
Differential Revision: https://reviews.llvm.org/D43380
llvm-svn: 325654
This is split off from D42948 and includes just the cases that constant fold to true or false. It also includes some refactoring to keep predicate checks together.
This supports things like
(setcc uge X, 0) -> true
Differential Revision: https://reviews.llvm.org/D43489
llvm-svn: 325627
SimplifyDemandedBits forces the demanded mask to all 1s if the node has multiple uses, unless the AssumeSingleUse flag is set.
So previously we were only really likely to simplify something if the condition had a single use. And on the off chance we did simplify with multiple uses the demanded mask being used was all ones so there was no reason to create a shrunkblend.
This patch now checks that the condition is only used by selects first, and then sets the AssumeSingleUse flag for the simplifcation. Then we convert the selects to shrunkblend, and finally replace condition.
Differential Revision: https://reviews.llvm.org/D43446
llvm-svn: 325604
DAGCombiner and SimplifySetCC both use getPointerTy for shift amounts pre-legalization. DAGCombiner uses a single helper function to hide this. SimplifySetCC does it in multiple places.
This patch adds a defaulted parameter to getShiftAmountTy that can make it return getPointerTy for scalar types. Use this parameter to simplify the SimplifySetCC and DAGCombiner.
Additionally, there were two places in SimplifySetCC that were creating shifts using the target's preferred shift amount pre-legalization. If the target uses a narrow type and the type is illegal, this can cause SimplfiySetCC to create a shift with an amount that can't represent all possible shift values for the type. To fix this we should use pointer type there too.
Alternatively we could make getScalarShiftAmountTy for each target return a safe value for large types as proposed in D43445. And maybe we should still do that, but fixing the SimplifySetCC code keeps other targets from tripping over this in the future.
Fixes PR36250.
Differential Revision: https://reviews.llvm.org/D43449
llvm-svn: 325602
This allows us to avoid an opsize prefix. And forcing some move immediates to i32 avoids a length changing prefix on those instructions.
This mostly replaces the existing combine we had for zext/sext+cmov of constants. I left in a case for sign extending a 32 bit cmov of constants to 64 bits.
Differential Revision: https://reviews.llvm.org/D43327
llvm-svn: 325601
For instructions like call foo and jmp foo patch changes
relocation produced from R_X86_64_PC32 to R_X86_64_PLT32.
Relocation can be used as a marker for 32-bit PC-relative branches.
Linker will reduce PLT32 relocation to PC32 if function is defined locally.
Differential revision: https://reviews.llvm.org/D43383
llvm-svn: 325569
The 128 and 256 bit versions were already not used by clang. This adds an equivalent unmasked 512 bit version. Then autoupgrades all sizes to use unmasked intrinsics plus select.
llvm-svn: 325559
Previously we used vptestmd, but the scheduling data for SKX says vpmovq2m/vpmovd2m is lower latency. We already used vpmovb2m/vpmovw2m for byte/word truncates. So this is more consistent anyway.
llvm-svn: 325534
We swapped the operands and used setle, but I don't see any reason to do that. I think this is a holdover from SSE where we swap and the invert to use pcmpgt. But with AVX512 we don't want an invert so we won't use pcmpgt. So there's no need to swap.
llvm-svn: 325527
Canonicalize EQ/NE PCMPM to have build vector all zeros on the RHS so we don't have to pattern match it in both locations. This significantly reduces the number of isel patterns needed since we also had to multiply it out with loads being in either operand of the 'and' input node and in the 'and' masking node.
This removes over 24000 bytes from the isel table.
llvm-svn: 325526
If we have a clamp pattern, SMIN(SMAX(X, LO),HI) or SMAX(SMIN(X, HI),LO) then we can deduce that the number of signbits (zeros/ones) will be at least the minimum of the LO and HI constants.
ComputeKnownBits equivalent of D43338.
Differential Revision: https://reviews.llvm.org/D43463
llvm-svn: 325521
It was reverted because it broke the grub build. The reason the grub
build broke is because grub does its own relocation processing and was
not handing R_386_PLT32. Since grub has no dynamic linker, the fix is
trivial: handle R_386_PLT32 exactly like R_386_PC32.
On the report it was noted that they are using
-fno-integrated-assembler. The upstream GAS (starting with
451875b4f976a527395e9303224c7881b65e12ed) will already be producing a
R_386_PLT32 anyway, so they have to update their code one way or the
other
Original message:
Don't assume a null GV is local for ELF and MachO.
This is already a simplification, and should help with avoiding a plt
reference when calling an intrinsic with -fno-plt.
With this change we return false for null GVs, so the caller only
needs to check the new metadata to decide if it should use foo@plt or
*foo@got.
llvm-svn: 325514
Previously we used the immediate encoding if the load was in operand 0 and the short encoding if the load was in operand 1.
This added an insane number of bytes to the size of the isel table. I'm wondering if we should always use the immediate form during isel and change to the short form during emission. This would remove the need to pattern match every combination for both the immediate form and the short form during isel. We could do the same with vpcmpgt
llvm-svn: 325456
If we have a clamp pattern, SMIN(SMAX(X, LO),HI) or SMAX(SMIN(X, HI),LO) then we can deduce that the number of signbits will be at least the minimum of the LO and HI constants.
I haven't bothered with the UMIN/UMAX equivalent as (1) we don't have any current use cases and (2) I wonder if we'd be better off immediately falling back for ComputeKnownBits for UMIN/UMAX which already has optimization patterns useful for unsigned cases.
Differential Revision: https://reviews.llvm.org/D43338
llvm-svn: 325450
This reverts commit r323991.
This commit breaks target that don't model all the register constraints
in TableGen. So far the workaround was to set the
hasExtraXXXRegAllocReq, but it proves that it doesn't cover all the
cases.
For instance, when mutating an instruction (like in the lowering of
COPYs) the isRenamable flag is not properly updated. The same problem
will happen when attaching machine operand from one instruction to
another.
Geoff Berry is working on a fix in https://reviews.llvm.org/D43042.
llvm-svn: 325421
Sadly, r324359 caused at least PR36312. There is a patch out for review
but it seems to be taking a bit and we've already had these crashers in
tree for too long. We're hitting this PR in real code now and are
blocked on shipping new compilers as a consequence so I'm reverting us
back to green.
Sorry for the churn due to the stacked changes that I had to revert. =/
llvm-svn: 325420
Summary:
Currently we convert to shuffles during lowering. This moves it to DAG combine so hopefully we can get it done before type legalization has to extend the condition.
I believe in some cases we're creating SHRUNKBLENDs that end up with constant conditions because we see the extended on the condition and think its a dynamic selelect before DAG combine gets a chance to constant fold the extend. We could add combines to turn SHRUNKBLENDs with constant condition back to vselect. But it seemed like it might be better to just send them to shuffles as early as possible so they never get a chance to become SHRUNKBLENDs. This the reason some tests went from blends controlled by a constant pool load to just move.
Some of the constant pool entries changed because the sign_extend introduced by type legalization turned undef elements in select condition into 0s. While the select->shuffle used -1 in the shuffle mask. So now the shuffle lowering can do what it wants with them.
I'll remove the lowering code as a follow up. We might be able to simplify some of the pre-checks for SHRUNKBLEND as the FIXME there says.
Reviewers: spatel, RKSimon, efriedma, zvi, andreadb
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D43367
llvm-svn: 325417
This patch changes GlobalISelEmitter to rank patterns similar to how the
DAG does it (ie it computes a score for a pattern and adds the added
complexity to it).
This is so that the decision tree for GISelSelector remains compatible
with that of SelectionDAG.
https://reviews.llvm.org/D43270
llvm-svn: 325401
This seems to interfere with a target independent brcond combine that looks for the (srl (and X, C1), C2) pattern to enable TEST instructions. Once we flip, that combine doesn't fire and we end up exposing it to the X86 specific BT combine which causes us to emit a BT instruction. BT has lower throughput than TEST.
We could try to make the brcond combine aware of the alternate pattern, but since the flip was just a code size reduction and not likely to enable other combines, it seemed easier to just delay it until after lowering.
Differential Revision: https://reviews.llvm.org/D43201
llvm-svn: 325371
Based off the DemandedElts mask the and UNDEF elements returned from the SimplifyDemandedVectorElts calls to the shuffle operands, we can attempt to simplify the shuffle mask.
I had to be very conservative here as accepting post-legalized shuffle masks could cause problems for targets that legalize UNDEF mask elements back to inrange values (PowerPC), similarly combining to identity shuffle masks could cause too much UNDEF information to disappear for later combines.
llvm-svn: 325354
We already do this for 64-bit when it won't fit into a 64-bit AND/TEST's immediate field. This adds an additional qualifier to do it for any single bit constant larger than 8-bits under optsize
Differential Revision: https://reviews.llvm.org/D43346
llvm-svn: 325290
We can use PACKSS to saturate each stage of the chain: PACKSSDW down to [-32768,32767] and then PACKSSWB to [-128,127].
PACKUS is a little trickier and will be handled in a separate patch.
llvm-svn: 325235
This is mainly a move of simplifyShuffleOperands from DAGCombiner::visitVECTOR_SHUFFLE to create a more general purpose TargetLowering::SimplifyDemandedVectorElts implementation.
Further features can be moved/added in future patches.
Differential Revision: https://reviews.llvm.org/D42896
llvm-svn: 325232
