I reinvented this functionality in http://reviews.llvm.org/D16828 because it was
hidden away as a static function. The changes in x86 are not based on a complete
audit. I suspect there are other possible uses there, and there are almost certainly
more potential users in other targets.
llvm-svn: 260295
As mentioned in http://reviews.llvm.org/D16828 , the related masked load transform
will need this logic, so I'm moving it out to make that patch smaller.
llvm-svn: 260240
On AVX2 target we are poorly legalizing SIGN_EXTEND ops for which the input's legalized type doesn't have the same number of elements as the destination, resulting in an ANY_EXTEND followed by a SIGN_EXTEND_INREG.
This patch uses the existing SIGN_EXTEND -> SIGN_EXTEND_VECTOR_INREG combine to extend the input to the size of the result and using SIGN_EXTEND_VECTOR_INREG instead.
Differential Revision: http://reviews.llvm.org/D16994
llvm-svn: 260210
As discussed on PR26491, this patch adds support for lowering v4f32 shuffles to the MOVLHPS/MOVHLPS instructions. It also adds support for memory folding with their MOVLPS/MOVHPS load equivalents.
This first patch only really helps SSE1 targets as SSE2+ targets will widen the shuffle mask and use v2f64 equivalents (although they still combine to MOVLHPS/MOVHLPS for v2f64 splats). This will have to be addressed in a future patch, most likely when we add support for binary target shuffle combines.
Differential Revision: http://reviews.llvm.org/D16956
llvm-svn: 260168
Another opportunity to reduce masked stores: in D16691, we decided not to attempt the 'one mask element is set'
transform in InstCombine, but this should be a win for any AVX machine.
Code comments note that this transform could be extended for other targets / cases.
Differential Revision: http://reviews.llvm.org/D16828
llvm-svn: 260145
This matches GCC and MSVC's behaviour, and saves on code size.
We were already not extending i1 return values on x86_64 after r127766. This
takes that patch further by applying it to x86 target as well, and also for i8
and i16.
The ABI docs have been unclear about the required behaviour here. The new i386
psABI [1] clearly states (Table 2.4, page 14) that i1, i8, and i16 return
vales do not need to be extended beyond 8 bits. The x86_64 ABI doc is being
updated to say the same [2].
Differential Revision: http://reviews.llvm.org/D16907
[1]. https://01.org/sites/default/files/file_attach/intel386-psabi-1.0.pdf
[2]. https://groups.google.com/d/msg/x86-64-abi/E8O33onbnGQ/_RFWw_ixDQAJ
llvm-svn: 260133
The combineX86ShufflesRecursively only supports unary shuffles, but was missing the opportunity to combine binary shuffles with a zero / undef second input.
This patch resolves target shuffle inputs, converting the shuffle mask elements to SM_SentinelUndef/SM_SentinelZero where possible. It then resolves the updated mask to check if we have created a faux unary shuffle.
Additionally, we now attempt to recursively call combineX86ShufflesRecursively for all input operands (we used to just recurse for unary integer shuffles and unary unpacks) - it safely returns early if its not a target shuffle.
Differential Revision: http://reviews.llvm.org/D16683
llvm-svn: 260063
Pulled out the code used by PSHUFB/VPERMV/VPERMV3 shuffle mask decoding into common helper functions.
The helper functions handle masks coming from BROADCAST/BUILD_VECTOR and ConstantPool nodes respectively.
llvm-svn: 260032
Choose between MOVD/MOVSS and MOVQ/MOVSD depending on the target vector type.
This has a lot fewer test changes than trying to add this to X86InstrInfo::setExecutionDomain.....
llvm-svn: 259816
This patch adds support for consecutive (load/undef elements) 32-bit loads, followed by trailing undef/zero elements to be combined to a single MOVD load.
Differential Revision: http://reviews.llvm.org/D16729
llvm-svn: 259796
Follow up to D16217 and D16729
This change uncovered an odd pattern where VZEXT_LOAD v4i64 was being lowered to a load of the lower v2i64 (so the 2nd i64 destination element wasn't being zeroed), I can't find any use/reason for this and have removed the pattern and replaced it so only the 1st i64 element is loaded and the upper bits all zeroed. This matches the description for X86ISD::VZEXT_LOAD
Differential Revision: http://reviews.llvm.org/D16768
llvm-svn: 259635
Minor patch to trace back through target shuffles to the source of the inserted element in a (V)INSERTPS shuffle.
Differential Revision: http://reviews.llvm.org/D16652
llvm-svn: 259343
Enable truncate 128/256bit packed byte/word with AVX512BW but without AVX512VL, use 512bit instructions.
Differential Revision: http://reviews.llvm.org/D16531
llvm-svn: 259044
This patch adds support for trailing zero elements to VZEXT_LOAD loads (and checks that no zero elts occur within the consecutive load).
It also generalizes the 64-bit VZEXT_LOAD load matching to work for loads other than 2x32-bit loads.
After this patch it will also be easier to add support for other basic load patterns like 32-bit VZEXT_LOAD loads, PMOVZX and subvector load insertion.
Differential Revision: http://reviews.llvm.org/D16217
llvm-svn: 258798
There's a special case in EmitLoweredSelect() that produces an improved
lowering for cmov(cmov) patterns. However this special lowering is
currently broken if the inner cmov has multiple users so this patch
stops using it in this case.
If you wonder why this wasn't fixed by continuing to use the special
lowering and inserting a 2nd PHI for the inner cmov: I believe this
would incur additional copies/register pressure so the special lowering
does not improve upon the normal one anymore in this case.
This fixes http://llvm.org/PR26256 (= rdar://24329747)
llvm-svn: 258729
VPMADD52LUQ - Packed Multiply of Unsigned 52-bit Integers and Add the Low 52-bit Products to Qword Accumulators
VPMADD52HUQ - Packed Multiply of Unsigned 52-bit Unsigned Integers and Add High 52-bit Products to 64-bit Accumulators
Differential Revision: http://reviews.llvm.org/D16407
llvm-svn: 258680
Generalised mask generation / subvector extraction to use the input/output types directly instead of an if/else through all the currently accepted types.
llvm-svn: 258645
If the INSERTPS zeroes out all the referenced elements from either of the 2 input vectors (and the input is not already UNDEF), then set that input to UNDEF to reduce dependencies.
llvm-svn: 258622
Better handling of the annoying pshuflw/pshufhw ops which only shuffle lower/upper halves of a vector.
Added vXi16 unary shuffle support for cases where i16 elements (from the same half of the source) are being splatted to the whole of one of the halves. This avoids the general lowering case which must shuffle the 32-bit elements first - meaning that we used to end up with unnecessary duplicate pshuflw/pshufhw shuffles.
Note this has the side effect of a lot of SSSE3 test cases no longer needing to use PSHUFB, as it falls below the 3 op combine threshold for when PSHUFB is typically worth it. I've raised PR26183 to discuss if the threshold should be changed and whether we need to make it more specific to the target CPU.
Differential Revision: http://reviews.llvm.org/D14901
llvm-svn: 258440
As vector shuffles can only reference two inputs many (V)INSERTPS patterns end up being split over two targets shuffles.
This patch adds combines to attempt to combine (V)INSERTPS nodes with input/output nodes that are just zeroing out these additional vector elements.
Differential Revision: http://reviews.llvm.org/D16072
llvm-svn: 258205
AVX2 can only broadcast from the zero'th element of a vector, but if the broadcastable element is the zero'th element of a 128-bit subvector its advantageous to extract the subvector, broadcast from that and avoid the loading of shuffle mask data that would be needed for VPERMPS/VPERMD. The only exception being when the source type is 4f64 or 4i64 which can directly use the immediate shuffle VPERMPD/VPERMQ directly.
Differential Revision: http://reviews.llvm.org/D16050
llvm-svn: 258081