ICMP instruction selection fails on SKX and KNL for i1 operand.
I use XOR to resolve:
(A == B) is equivalent to (A xor B) == 0
Differential Revision: http://reviews.llvm.org/D18511
llvm-svn: 264566
Currently this is to mainly to prevent scalarization of integer division by constants.
Differential Revision: http://reviews.llvm.org/D18307
llvm-svn: 264511
LowerMul v32i8 on AVX2 needs to split the 256-bit sources to allow sign-extension back to v16i16 to occur. Since this is basically the same as Lower256IntArith we simplify by using that here instead.
llvm-svn: 264506
LowerShift was using the same code as Lower256IntArith to split 256-bit vectors into 2 x 128-bit vectors, so now we just call Lower256IntArith.
llvm-svn: 264403
KTEST instruction may be used instead of TEST in this case:
%int_sel3 = bitcast <8 x i1> %sel3 to i8
%res = icmp eq i8 %int_sel3, zeroinitializer
br i1 %res, label %L2, label %L1
Differential Revision: http://reviews.llvm.org/D18444
llvm-svn: 264298
This patch begins adding support for lowering to the XOP VPPERM instruction - adding the X86ISD::VPPERM opcode.
Differential Revision: http://reviews.llvm.org/D18189
llvm-svn: 264260
This should be hoisted further up so it can be used in DAGCombiner and other backends,
but I'm limiting the scope in the interest of patch minimalism.
It's not quite NFC because some of the replaced code was using an 'if' check rather
than a 'while' loop, so those cases would only look through a single bitcast.
llvm-svn: 264186
Improve vector extension of vectors on hardware without dedicated VSEXT/VZEXT instructions.
We already convert these to SIGN_EXTEND_VECTOR_INREG/ZERO_EXTEND_VECTOR_INREG but can further improve this by using the legalizer instead of prematurely splitting into legal vectors in the combine as this only properly helps for lowering to VSEXT/VZEXT.
Removes a lot of unnecessary any_extend + mask pattern - (Fix for PR25718).
Reapplied with a fix for PR26953 (missing vector widening legalization).
Differential Revision: http://reviews.llvm.org/D17932
llvm-svn: 264062
Improve computeZeroableShuffleElements to be able to peek through bitcasts to extract zero/undef values from BUILD_VECTOR nodes of different element sizes to the shuffle mask.
Differential Revision: http://reviews.llvm.org/D14261
llvm-svn: 263906
We were being too aggressive in trying to combine a shuffle into a blend-with-zero pattern, often resulting in a endless loop of contrasting combines
This patch stops the combine if we already have a blend in place (means we miss some domain corrections)
llvm-svn: 263717
Converting masked vector loads to regular vector loads for x86 AVX should always be a win.
I raised the legality issue of reading the extra memory bytes on llvm-dev. I did not see any
objections.
1. x86 already does this kind of optimization for multiple scalar loads -> vector load.
2. If other targets have the same flexibility, we could move this transform up to CGP or DAGCombiner.
Differential Revision: http://reviews.llvm.org/D18094
llvm-svn: 263446
The SSE41 v8i16 shift lowering using (v)pblendvb is great for non-constant shift amounts, but if it is constant then we can efficiently reduce the VSELECT to shuffles with the pre-SSE41 lowering.
llvm-svn: 263383
cmpxchg[8|16]b uses RBX as one of its argument.
In other words, using this instruction clobbers RBX as it is defined to hold one
the input. When the backend uses dynamically allocated stack, RBX is used as a
reserved register for the base pointer.
Reserved registers have special semantic that only the target understands and
enforces, because of that, the register allocator don’t use them, but also,
don’t try to make sure they are used properly (remember it does not know how
they are supposed to be used).
Therefore, when RBX is used as a reserved register but defined by something that
is not compatible with that use, the register allocator will not fix the
surrounding code to make sure it gets saved and restored properly around the
broken code. This is the responsibility of the target to do the right thing with
its reserved register.
To fix that, when the base pointer needs to be preserved, we use a different
pseudo instruction for cmpxchg that save rbx.
That pseudo takes two more arguments than the regular instruction:
- One is the value to be copied into RBX to set the proper value for the
comparison.
- The other is the virtual register holding the save of the value of RBX as the
base pointer. This saving is done as part of isel (i.e., we emit a copy from
rbx).
cmpxchg_save_rbx <regular cmpxchg args>, input_for_rbx_reg, save_of_rbx_as_bp
This gets expanded into:
rbx = copy input_for_rbx_reg
cmpxchg <regular cmpxchg args>
rbx = save_of_rbx_as_bp
Note: The actual modeling of the pseudo is a bit more complicated to make sure
the interferes that appears after the pseudo gets expanded are properly modeled
before that expansion.
This fixes PR26883.
llvm-svn: 263325
Improve vector extension of vectors on hardware without dedicated VSEXT/VZEXT instructions.
We already convert these to SIGN_EXTEND_VECTOR_INREG/ZERO_EXTEND_VECTOR_INREG but can further improve this by using the legalizer instead of prematurely splitting into legal vectors in the combine as this only properly helps for lowering to VSEXT/VZEXT.
Removes a lot of unnecessary any_extend + mask pattern - (Fix for PR25718).
Differential Revision: http://reviews.llvm.org/D17932
llvm-svn: 263303
Its not enough that we test for SSSE3 - that's only OK for 128-bit vectors - we also need to test for AVX2 / AVX512BW for 256/512 bit vector cases.
llvm-svn: 263239
Looking at the IR definition of a masked load made me realize
there was no reason to use a shuffle here, so we don't need
to convert the format of the mask at all.
llvm-svn: 263167
Generalise the existing SIGN_EXTEND to SIGN_EXTEND_VECTOR_INREG combine to support zero extension as well and get rid of a lot of unnecessary ANY_EXTEND + mask patterns.
Reapplied with a fix for PR26870 (avoid premature use of TargetConstant in ZERO_EXTEND_VECTOR_INREG expansion).
Differential Revision: http://reviews.llvm.org/D17691
llvm-svn: 263159
This patch reorders the combining of target shuffle masks so that when a unary shuffle takes a binary shuffle as its input but only references one of its inputs it can correctly combine into a unary shuffle mask.
This is starting to encroach on the purpose of resolveTargetShuffleInputs, but I don't want to remove it until we definitely know we won't need it for full binary shuffle combining.
There is a lot more work before we can properly support binary target shuffle masks but this was an easy case to add support for.
Differential Revision: http://reviews.llvm.org/D17858
llvm-svn: 263102
Operation SCALAR_TO_VECTOR for v64i8 and v32i16 should be lowered if BW feature is "on".
Differential Revision: http://reviews.llvm.org/D17994
llvm-svn: 263097
Instead of a variable-blend instruction, form a blend with immediate because those are always cheaper.
Differential Revision: http://reviews.llvm.org/D17899
llvm-svn: 263067
The fix consisting in using the library call for atomic compare and swap when
the instruction is not safe to use may be incorrect. Indeed the library call may
not exist on all platform. In other words, we need a better fix!
llvm-svn: 262943
Patch to add support for target shuffle combining of X86ISD::VPERMV3 nodes, including support for detecting unary shuffles.
This uncovered several issues with the X86ISD::VPERMV3 shuffle mask decoding of non-64 bit shuffle mask elements - the bit masking wasn't being correctly computed.
Removed non-constant pool mask decode path as we have no way of testing it right now.
Differential Revision: http://reviews.llvm.org/D17916
llvm-svn: 262809
Added support for decoding VPERMILPS variable shuffle masks that aren't in the constant pool.
Added target shuffle mask decoding for SCALAR_TO_VECTOR+VZEXT_MOVL cases - these can happen for v2i64 constant re-materialization
Followup to D17681
llvm-svn: 262784
When the lowering of the setjmp intrinsic requires
a global base pointer to be set, make sure such pointer
gets defined by the CGBR pass.
This fixes PR26742.
llvm-svn: 262762
cmpxchgXXb uses RBX as one of its implicit argument. I.e., when
we use that instruction we need to clobber RBX. This is generally
fine, expect when RBX is a reserved register because in that case,
the register allocator will not track its value and will not
save and restore it when interferences occur.
rdar://problem/24851412
llvm-svn: 262759
The x86 ret instruction has a 16 bit immediate indicating how many bytes
to pop off of the stack beyond the return address.
There is a problem when extremely large structs are passed by value: we
might not be able to fit the number of bytes to pop into the return
instruction.
To fix this, expand RET_FLAG a little later and use a special sequence
to clean the stack:
pop %ecx ; return address is now in %ecx
add $n, %esp ; clean the stack
push %ecx ; bring the return address back on the stack
ret ; pop the return address and jmp to it's value
llvm-svn: 262755
The variable mask form of VPERMILPD/VPERMILPS were only partially implemented, with much of it still performed as an intrinsic.
This patch properly defines the instructions in terms of X86ISD::VPERMILPV, permitting the opcode to be easily combined as a target shuffle.
Differential Revision: http://reviews.llvm.org/D17681
llvm-svn: 262635
That's not the case for VPERMV/VPERMV3, which cover all possible
combinations (the C intrinsics use a different order; the AVX vs
AVX512 intrinsics are different still).
Since:
r246981 AVX-512: Lowering for 512-bit vector shuffles.
VPERMV is recognized in getTargetShuffleMask.
This breaks assumptions in most callers, as they expect
the non-mask operands to start at index 0.
VPERMV has the mask as operand #0; VPERMV3 has it in the middle.
Instead of the faulty assumption, have getTargetShuffleMask return
its operands as well.
One alternative we considered was to change the operand order of
VPERMV, but we agreed to stick to the instruction order, as there
are more AVX512 weirdness to cover (vpermt2/vpermi2 in particular).
Differential Revision: http://reviews.llvm.org/D17041
llvm-svn: 262627
Generalise the existing SIGN_EXTEND to SIGN_EXTEND_VECTOR_INREG combine to support zero extension as well and get rid of a lot of unnecessary ANY_EXTEND + mask patterns.
Differential Revision: http://reviews.llvm.org/D17691
llvm-svn: 262599
The code was previously not able to track a boolean argument
at a call site back to the formal argument of the caller.
Differential Revision: http://reviews.llvm.org/D17786
llvm-svn: 262575
Catch objects with a displacement of zero do not initialize a catch
object. The displacement is relative to %rsp at the end of the
function's prologue for x86_64 targets.
If we place an object at the top-of-stack, we will end up wit a
displacement of zero resulting in our catch object remaining
uninitialized.
Address this by creating our catch objects as fixed objects. We will
ensure that the UnwindHelp object is created after the catch objects so
that no catch object will have a displacement of zero.
Differential Revision: http://reviews.llvm.org/D17823
llvm-svn: 262546
This reverts commit r262370.
It turns out there is code out there that does sequences of allocas
greater than 4K: http://crbug.com/591404
The goal of this change was to improve the code size of inalloca call
sequences, but we got tangled up in the mess of dynamic allocas.
Instead, we should come back later with a separate MI pass that uses
dominance to optimize the full sequence. This should also be able to
remove the often unneeded stacksave/stackrestore pairs around the call.
llvm-svn: 262505
We have a number of useful lowering strategies for VBROADCAST instructions (both from memory and register element 0) which the 128-bit form of the MOVDDUP instruction can make use of.
This patch tweaks lowerVectorShuffleAsBroadcast to enable it to broadcast 2f64 args using MOVDDUP as well.
It does require a slight tweak to the lowerVectorShuffleAsBroadcast mechanism as the existing MOVDDUP lowering uses isShuffleEquivalent which can match binary shuffles that can lower to (unary) broadcasts.
Differential Revision: http://reviews.llvm.org/D17680
llvm-svn: 262478
We modeled the RDFLAGS{32,64} operations as "using" {E,R}FLAGS.
While technically correct, this is not be desirable for folks who want
to examine aspects of the FLAGS register which are not related to
computation like whether or not CPUID is a valid instruction.
Differential Revision: http://reviews.llvm.org/D17782
llvm-svn: 262465
This isn't quite NFC because some of the SDLocs may change which could
cause scheduling differences. But no regression tests are affected and
there is no functional change intended.
llvm-svn: 262391
The _chkstk function is called by the compiler to probe the stack in an
order consistent with Windows' expectations. However, it is possible to
elide the call to _chkstk and manually adjust the stack pointer if we
can prove that the allocation is fixed size and smaller than the probe
size.
This shrinks chrome.dll, chrome_child.dll and chrome.exe by a
cummulative ~133 KB.
Differential Revision: http://reviews.llvm.org/D17679
llvm-svn: 262370
In the code below on 32-bit targets, x would previously get forwarded to g()
without sign-extension to 32 bits as required by the parameter attribute.
void g(signed short);
void f(unsigned short x) {
g(x);
}
llvm-svn: 262352
This is long-standing dirtiness, as acknowledged by r77582:
The current trick is to select it into a merge_values with
the first definition being an implicit_def. The proper solution is
to add new ISD opcodes for the no-output variant.
Doing this before selection will let us combine away some constructs.
Differential Revision: http://reviews.llvm.org/D17659
llvm-svn: 262244
This is one of the cases shown in:
https://llvm.org/bugs/show_bug.cgi?id=26701
Shift and negate is what InstCombine appears to prefer, so I've started with that pattern.
Note that the 'pcmpeq' instructions are always generating the negative one for the actual
'pcmpgt' comparison in each case (side note: why isn't there an alias mnemonic for that?).
Differential Revision: http://reviews.llvm.org/D17630
llvm-svn: 262036
Part 2 of 2
This patch add support for combining target shuffles into blends-with-zero.
Differential Revision: http://reviews.llvm.org/D17483
llvm-svn: 261745
Part 1 of 2
This patch attempts to replace the insertion of zero scalars with a vector blend with zero, avoiding the use of the integer insertion instructions (which are particularly slow on many targets).
(Part 2 will add support for combining multiple blends-with-zero).
Differential Revision: http://reviews.llvm.org/D17483
llvm-svn: 261743
PerformShuffleCombine should be usable by unary and binary target shuffles, but was attempting to get the first two operands whatever the instruction type. Since these are only used for VECTOR_SHUFFLE instructions for one particular combine I've moved them inside the relevant if statement.
llvm-svn: 261727
Add support for the case where we have a consecutive load (which must include the first + last elements) with a mixture of undef/zero elements. We load the vector and then apply a shuffle to clear the zero'd elements.
Differential Revision: http://reviews.llvm.org/D17297
llvm-svn: 261490
Fixed a bug introduced by D16683 when a binary shuffle is simplified to a unary shuffle (with undef/zero sentinel mask indices) - if this resulted in only the second input being used combineX86ShuffleChain failed to take this into account and still referenced the first input.
llvm-svn: 261434
First small step towards fixing PR26667 - we need to ensure that combineX86ShuffleChain only gets called with a valid shuffle input node (a similar issue was found in D17041).
llvm-svn: 261433
TLSADDR nodes are lowered into actuall calls inside MC. In order to prevent
shrink-wrapping from pushing prologue/epilogue past them (which result
in TLS variables being accessed before the stack frame is set up), we
put markers, so that the stack gets adjusted properly.
Thanks to Quentin Colombet for guidance/help on how to fix this problem!
llvm-svn: 261387
This is effectively NFC because Atom is the only in-order x86 subtarget currently,
but the predicate would have become wrong if any other in-order CPU came along.
See related discussion in:
http://reviews.llvm.org/D16836
llvm-svn: 261275
In r260133, LLVM was changed to no longer extend i8/i16 return values,
as it's not required by the ABI. However, code was found in the wild
that relies on the old behaviour on Darwin, so this commit reverts
back to that old behaviour for Darwin.
On other platforms, it's less likely that code would be depending on
the old behaviour, as GCC and MSVC haven't been extending such return
values.
llvm-svn: 261235
Bug description:
The bug was discovered when test was compiled with -O0.
In case scatter result is DAG root , VectorLegalizer failed (assert) due to LowerMSCATTER() return kmask as result.
Change LowerMSCATTER() to return chain as original node do.
Differential Revision: http://reviews.llvm.org/D17331
llvm-svn: 261090
AVX1 doesn't support the shuffling of 256-bit integer vectors. For 32/64-bit elements we get around this by shuffling as float/double but for 8/16-bit elements (assuming they can't widen) we currently just split, shuffle as 128-bit vectors and concatenate the results back.
This patch adds the ability to lower using the bit-blend patterns before defaulting to the splitting behaviour.
Part 2 of 2
Differential Revision: http://reviews.llvm.org/D17292
llvm-svn: 261082
AVX1 doesn't support the shuffling of 256-bit integer vectors. For 32/64-bit elements we get around this by shuffling as float/double but for 8/16-bit elements (assuming they can't widen) we currently just split, shuffle as 128-bit vectors and concatenate the results back.
This patch adds the ability to lower using the bit-mask patterns before defaulting to the splitting behaviour. In some cases this ends up matching what AVX2 would do anyhow or what AVX1 does on the split vectors.
Part 1 of 2
Differential Revision: http://reviews.llvm.org/D17292
llvm-svn: 261081
Avoid reuse of operand variables, keep them local to a particular lowering - the operand collection is unique to each case anyhow.
Renamed from V to Ops to more closely match their purpose.
llvm-svn: 261078
Currently, we sometimes miscompile this vector pattern:
(c ? -v : v)
We lower it to (because "c" is <4 x i1>, lowered as a vector mask):
(~c & v) | (c & -v)
When we have SSSE3, we incorrectly lower that to PSIGN, which does:
(c < 0 ? -v : c > 0 ? v : 0)
in other words, when c is either all-ones or all-zero:
(c ? -v : 0)
While this is an old bug, it rarely triggers because the PSIGN combine
is too sensitive to operand order. This will be improved separately.
Note that the PSIGN tests are also incorrect. Consider:
%b.lobit = ashr <4 x i32> %b, <i32 31, i32 31, i32 31, i32 31>
%sub = sub nsw <4 x i32> zeroinitializer, %a
%0 = xor <4 x i32> %b.lobit, <i32 -1, i32 -1, i32 -1, i32 -1>
%1 = and <4 x i32> %a, %0
%2 = and <4 x i32> %b.lobit, %sub
%cond = or <4 x i32> %1, %2
ret <4 x i32> %cond
if %b is zero:
%b.lobit = <4 x i32> zeroinitializer
%sub = sub nsw <4 x i32> zeroinitializer, %a
%0 = <4 x i32> <i32 -1, i32 -1, i32 -1, i32 -1>
%1 = <4 x i32> %a
%2 = <4 x i32> zeroinitializer
%cond = or <4 x i32> %a, zeroinitializer
ret <4 x i32> %a
whereas we currently generate:
psignd %xmm1, %xmm0
retq
which returns 0, as %xmm1 is 0.
Instead, use a pure logic sequence, as described in:
https://graphics.stanford.edu/~seander/bithacks.html#ConditionalNegate
Fixes PR26110.
Differential Revision: http://reviews.llvm.org/D17181
llvm-svn: 261023
If KMOVB not supported (require AVX512DQ) only KMOVW can be used so store size should be 2 bytes.
Differential Revision: http://reviews.llvm.org/D17138
llvm-svn: 260878
This patch attempts to represent a shuffle as a repeating shuffle (recognisable by is128BitLaneRepeatedShuffleMask) with the source input(s) in their original lanes, followed by a single permutation of the 128-bit lanes to their final destinations.
On AVX2 we can additionally attempt to match using 64-bit sub-lane permutation. AVX2 can also now match a similar 'broadcasted' repeating shuffle.
This patch has several benefits:
* Avoids prematurely matching with lowerVectorShuffleByMerging128BitLanes which can require both inputs to have their input lanes permuted before shuffling.
* Can replace PERMPS/PERMD instructions - although these are useful for cross-lane unary shuffling, they require their shuffle mask to be pre-loaded (and increase register pressure).
* Matching the repeating shuffle makes use of a lot of existing shuffle lowering.
There is an outstanding minor AVX1 regression (combine_unneeded_subvector1 in vector-shuffle-combining.ll) of a previously 128-bit shuffle + subvector splat being converted to a subvector splat + (2 instruction) 256-bit shuffle, I intend to fix this in a followup patch for review.
Differential Revision: http://reviews.llvm.org/D16537
llvm-svn: 260834
As shown in:
https://llvm.org/bugs/show_bug.cgi?id=23203
...we currently die because lowering believes that mfence is allowed without SSE2 on x86-64,
but the instruction def doesn't know that.
I don't know if allowing mfence without SSE is right, but if not, at least now it's consistently wrong. :)
Differential Revision: http://reviews.llvm.org/D17219
llvm-svn: 260828
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
Added support for the extraction of the upper 128-bit subvectors for lower/upper half undef shuffles if it would reduce the number of extractions/insertions or avoid loads of AVX2 permps/permd shuffle masks.
Minor follow up to D15477.
llvm-svn: 258000
FIXME: Add more targets to use emutls into clang/test/Driver/emulated-tls.cpp.
FIXME: Add cygwin tests into llvm/test/CodeGen/X86. Working in progress.
llvm-svn: 257984
When we have a single basic block, the explicit copy-back instructions should
be inserted right before the terminator. Before this fix, they were wrongly
placed at the beginning of the basic block.
I will commit fixes to other platforms as well.
PR26136
llvm-svn: 257925
We rely on HasOpaqueSPAdjustment not changing after we've calculated
things based on it. Things like whether or not we can use 'rep;movs' to
copy bytes around, that sort of thing. If it changes, invariants in the
backend will quietly break. This situation arose when we had a call to
memcpy *and* a COPY of the FLAGS register where we would attempt to
reference local variables using %esi, a register that was clobbered by
the 'rep;movs'.
This fixes PR26124.
llvm-svn: 257730
AVX1 v8i32/v4i64 shuffles are bitcasted to v8f32/v4f64, this patch peeks through any bitcast to check for a load node to allow broadcasts to occur.
This is a re-commit of r257055 after r257264 fixed 32-bit broadcast loads of i64 scalars.
llvm-svn: 257266
AVX1 v8i32/v4i64 shuffles are bitcasted to v8f32/v4f64, this patch peeks through bitcasts to check for a load node to allow broadcasts to occur.
Follow up to D15310
llvm-svn: 257055
Follow up to D15378, added INSERTPS to the list of decodable target shuffles and enabled XFormVExtractWithShuffleIntoLoad to handle target shuffles with SentinelZero and tested this with INSERTPS.
llvm-svn: 257046
getTargetShuffleMask may return shuffle masks with SM_SentinelZero (-2) values (currently just for PSHUFB but VPERM2X128 as well with this patch). Although some calling functions can make use of this (mainly for shuffle combining), others can not and their inclusion makes shuffle mask comparisons more difficult.
This patch adds a flag to getTargetShuffleMask to indicate if the calling function can't handle SM_SentinelZero; getTargetShuffleMask will then return false if it occurs to make handling much easier.
I've tidied up some uses of getTargetShuffleMask to better indicate what is going on - more could be done but at present I don't have test cases to demonstrate it.
Some upcoming patches will make use of this to both support more uses where SM_SentinelZero is not permitted (e.g. combineShuffleToAddSub), and also will allow us to add INSERTPS support to getTargetShuffleMask as part of better zero handling discussed in D14261.
Differential Revision: http://reviews.llvm.org/D15378
llvm-svn: 256992
As discussed on D15378, move the mask.empty() tests to after the switch statement and consider any shuffle decode where the extracted target shuffle mask is empty as a failure.
llvm-svn: 256921
We queried hasFP before we hit ExpandISelPseudos. ExpandISelPseudos
manipulated state that hasFP relied on, potentially changing the result
after it has been queried elsewhere.
While I am not aware of any particular bug due to this state of affairs,
it seems best to avoid it entirely by changing the state during DAG
construction.
llvm-svn: 256849
PBLEND/BLENDPD/BLENDPS are no different to the other target shuffles and this will make future improvements to the target shuffle combines more straightforward.
llvm-svn: 256819
We need a frame pointer if there is a push/pop sequence after the
prologue in order to unwind the stack. Scanning the instructions to
figure out if this happened made hasFP not constant-time which is a
violation of expectations. Let's compute this up-front and reuse that
computation when we need it.
llvm-svn: 256730
LLVM's targets need to know if stack pointer adjustments occur after the
prologue. This is needed to correctly determine if the red-zone is
appropriate to use or if a frame pointer is required.
Normally, LLVM can figure this out very precisely by reasoning about the
contents of the MachineFunction. There is an interesting corner case:
inline assembly.
The vast majority of inline assembly which will perform a push or pop is
done so to pair up with pushf or popf as appropriate. Unfortunately,
this inline assembly doesn't mark the stack pointer as clobbered
because, well, it isn't. The stack pointer is decremented and then
immediately incremented. Because of this, LLVM was changed in r256456
to conservatively assume that inline assembly contain a sequence of
stack operations. This is unfortunate because the vast majority of
inline assembly will not end up manipulating the stack pointer in any
way at all.
Instead, let's provide a more principled solution: an intrinsic.
FWIW, other compilers (MSVC and GCC among them) also provide this
functionality as an intrinsic.
llvm-svn: 256685
This adds support for the MCU psABI in a way different from r251223 and r251224,
basically reverting most of these two patches. The problem with the approach
taken in r251223/4 is that it only handled libcalls that originated from the backend.
However, the mid-end also inserts quite a few libcalls and assumes these use the
platform's default calling convention.
The previous patch tried to insert inregs when necessary both in the FE and,
somewhat hackily, in the CG. Instead, we now define a new default calling convention
for the MCU, which doesn't use inreg marking at all, similarly to what x86-64 does.
Differential Revision: http://reviews.llvm.org/D15054
llvm-svn: 256494
lower broadcast<type>x<vector> to shuffles.
there are two cases:
1.src is 128 bits and dest is 512 bits: in this case we will lower it to shuffle with imm = 0.
2.src is 256 bit and dest is 512 bits: in this case we will lower it to shuffle with imm = 01000100b (0x44) that way we will broadcast the 256bit source: ymm[0,1,2,3] => zmm[0,1,2,3,0,1,2,3] then it will mask it with the passthru value (in case it's mask op).
Differential Revision: http://reviews.llvm.org/D15790
llvm-svn: 256490
Fix TRUNCATE lowering vector to vector i1, use LSB and not MSB.
Implement VPMOVB/W/D/Q2M intrinsic.
Differential Revision: http://reviews.llvm.org/D15675
llvm-svn: 256470
First step towards making better use of AVX's implicit zeroing of the upper half of a 256-bit vector by instructions that only act on the lower 128-bit vector - discussed on D14151.
As well as the fact that 128-bit shuffle instructions are generally more capable, this can be performant for older CPUs with 128-bit ALUs (e.g. Jaguar, Sandy Bridge) that must treat 256-bit vectors as multiple micro-ops.
Moved the similar subvector extraction shuffle combines from PerformShuffleCombine256 to lowerVectorShuffle as well.
Note: I've avoided combining shuffles that reference elements from the upper halves of the input vectors - this may be reviewed in future work as well (AVX1 would probably always gain, but AVX2 does have some cross-lane shuffle instructions).
Differential Revision: http://reviews.llvm.org/D15477
llvm-svn: 256332
This patch transforms truncation between vectors of integers into
X86ISD::PACKUS/PACKSS operations during DAG combine. We don't do it in
lowering phase because after type legalization, the original truncation
will be turned into a BUILD_VECTOR with each element that is extracted
from a vector and then truncated, and from them it is difficult to do
this optimization. This greatly improves the performance of truncations
on some specific types.
Cost table is updated accordingly.
Differential revision: http://reviews.llvm.org/D14588
llvm-svn: 256194
It resolves clang selfhosting with std::once() for Cygwin.
FIXME: It may be EmulatedTLS-generic also for X86-Android.
FIXME: Pass EmulatedTLS to LLVM CodeGen from Clang with -femulated-tls.
llvm-svn: 256134
This folds (ashr (shl a, [56,48,32,24,16]), SarConst)
into (shl, (sext (a), [56,48,32,24,16] - SarConst))
or into (lshr, (sext (a), SarConst - [56,48,32,24,16]))
depending on sign of (SarConst - [56,48,32,24,16])
sexts in X86 are MOVs.
The MOVs have the same code size as above SHIFTs (only SHIFT by 1 has lower code size).
However the MOVs have 2 advantages to SHIFTs on x86:
1. MOVs can write to a register that differs from source.
2. MOVs accept memory operands.
This fixes PR24373.
Patch by: evgeny.v.stupachenko@intel.com
Differential Revision: http://reviews.llvm.org/D13161
llvm-svn: 255761
It adjusts from RSP-after-prologue to RBP, which is what SEH filters
need to do before they can use llvm.localrecover.
Fixes SEH filter captures, which were broken in r250088.
Issue reported by Alex Crichton.
llvm-svn: 255707
This patch improves on the suggested codegen from PR24475:
https://llvm.org/bugs/show_bug.cgi?id=24475
but only for the fmaxf() case to start, so we can sort out any bugs before
extending to fmin, f64, and vectors.
The fmax / maxnum definitions provide us flexibility for signed zeros, so the
only thing we have to worry about in this replacement sequence is NaN handling.
Note 1: It may be better to implement this as lowerFMAXNUM(), but that exposes
a problem: SelectionDAGBuilder::visitSelect() transforms compare/select
instructions into FMAXNUM nodes if we declare FMAXNUM legal or custom. Perhaps
that should be checking for NaN inputs or global unsafe-math before transforming?
As it stands, that bypasses a big set of optimizations that the x86 backend
already has in PerformSELECTCombine().
Note 2: The v2f32 test reveals another bug; the vector is extended to v4f32, so
we have completely unnecessary operations happening on undef elements of the
vector.
Differential Revision: http://reviews.llvm.org/D15294
llvm-svn: 255700
Full type legalizer that works with all vectors length - from 2 to 16, (i32, i64, float, double).
This intrinsic, for example
void @llvm.masked.scatter.v2f32(<2 x float>%data , <2 x float*>%ptrs , i32 align , <2 x i1>%mask )
requires type widening for data and type promotion for mask.
Differential Revision: http://reviews.llvm.org/D13633
llvm-svn: 255629
Part 1 was submitted in http://reviews.llvm.org/D15134.
Changes in this part:
* X86RegisterInfo.td, X86RecognizableInstr.cpp: Add FR128 register class.
* X86CallingConv.td: Pass f128 values in XMM registers or on stack.
* X86InstrCompiler.td, X86InstrInfo.td, X86InstrSSE.td:
Add instruction selection patterns for f128.
* X86ISelLowering.cpp:
When target has MMX registers, configure MVT::f128 in FR128RegClass,
with TypeSoftenFloat action, and custom actions for some opcodes.
Add missed cases of MVT::f128 in places that handle f32, f64, or vector types.
Add TODO comment to support f128 type in inline assembly code.
* SelectionDAGBuilder.cpp:
Fix infinite loop when f128 type can have
VT == TLI.getTypeToTransformTo(Ctx, VT).
* Add unit tests for x86-64 fp128 type.
Differential Revision: http://reviews.llvm.org/D11438
llvm-svn: 255558
Summary: This patch adds support of conversion (mul x, 2^N + 1) => (add (shl x, N), x) and (mul x, 2^N - 1) => (sub (shl x, N), x) if the multiplication can not be converted to LEA + SHL or LEA + LEA. LLVM has already supported this on ARM, and it should also be useful on X86. Note the patch currently only applies to cases where the constant operand is positive, and I am planing to add another patch to support negative cases after this.
Reviewers: craig.topper, RKSimon
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D14603
llvm-svn: 255415
Summary: This patch adds support of conversion (mul x, 2^N + 1) => (add (shl x, N), x) and (mul x, 2^N - 1) => (sub (shl x, N), x) if the multiplication can not be converted to LEA + SHL or LEA + LEA. LLVM has already supported this on ARM, and it should also be useful on X86. Note the patch currently only applies to cases where the constant operand is positive, and I am planing to add another patch to support negative cases after this.
Reviewers: craig.topper, RKSimon
Subscribers: aemerson, llvm-commits
Differential Revision: http://reviews.llvm.org/D14603
llvm-svn: 255391
On AVX and AVX2, BROADCAST instructions can load a scalar into all elements of a target vector.
This patch improves the lowering of 'splat' shuffles of a loaded vector into a broadcast - currently the lowering only works for cases where we are splatting the zero'th element, which is now generalised to any element.
Fix for PR23022
Differential Revision: http://reviews.llvm.org/D15310
llvm-svn: 255061
FP logic instructions are supported in DQ extension on AVX-512 target.
I use integer operations instead.
Added tests.
I also enabled FABS in this patch in order to check ANDPS.
The operations are FOR, FXOR, FAND, FANDN.
The instructions, that supported for 512-bit vector under DQ are:
VORPS/PD, VXORPS/PD, VANDPS/PD, FANDNPS/PD.
Differential Revision: http://reviews.llvm.org/D15110
llvm-svn: 254913
Patterns were missing for KNL target for <8 x i32>, <8 x float> masked load/store.
This intrinsic comes with all legal types:
<8 x float> @llvm.masked.load.v8f32(<8 x float>* %addr, i32 align, <8 x i1> %mask, <8 x float> %passThru),
but still requires lowering, because VMASKMOVPS, VMASKMOVDQU32 work with 512-bit vectors only.
All data operands should be widened to 512-bit vector.
The mask operand should be widened to v16i1 with zeroes.
Differential Revision: http://reviews.llvm.org/D15265
llvm-svn: 254909
These instructions are not supported by all CPUs in 64-bit mode. Emitting them
causes Chromium to crash on start-up for users with such chips.
(GCC puts these instructions behind -msahf on 64-bit for the same reason.)
This patch adds FeatureLAHFSAHF, enables it by default for 32-bit targets
and modern CPUs, and changes X86InstrInfo::copyPhysReg back to the lowering
from before r244503 when the instructions are not available.
Differential Revision: http://reviews.llvm.org/D15240
llvm-svn: 254793
Summary:
These ADJCALLSTACK markers don't generate code, but they keep dynamic
alloca code that calls chkstk out of the prologue.
This slightly pessimizes inalloca calls by preventing some register copy
coalescing, but I can live with that.
Reviewers: qcolombet
Subscribers: hans, llvm-commits
Differential Revision: http://reviews.llvm.org/D15200
llvm-svn: 254645
On FMA targets, we can avoid having to load a constant to negate a float/double multiply by instead using a FNMSUB (-(X*Y)-0)
Fix for PR24366
Differential Revision: http://reviews.llvm.org/D14909
llvm-svn: 254495
We could already recognise shuffle(FSUB, FADD) -> ADDSUB, this allow us to recognise shuffle(FADD, FSUB) -> ADDSUB by commuting the shuffle mask prior to matching.
llvm-svn: 254259
Summary:
Many target lowerings copy-paste the code to test SDValues for known constants.
This code can instead be shared in SelectionDAG.cpp, and reused in the targets.
Reviewers: MatzeB, andreadb, tstellarAMD
Subscribers: arsenm, jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D14945
llvm-svn: 254085
It was wrong order of operands (from intrinsic to DAG node).
I added more strict type specification for instruction selection.
Differential Revision: http://reviews.llvm.org/D14942
llvm-svn: 254059
X86 needs to use its own FMA opcodes, preventing the standard FNEG(FMA) pattern table recognition method used by other platforms. This patch adds support for lowering FNEG(FMA(X,Y,Z)) into a single suitably negated FMA instruction.
Fix for PR24364
Differential Revision: http://reviews.llvm.org/D14906
llvm-svn: 254016
This patch fixes the following issues:
1. Fix the return type of X86psadbw: it should not be the same type of inputs.
For vNi8 inputs the output should be vMi64, where M = N/8.
2. Fix the return type of int_x86_avx512_psad_bw_512 accordingly.
3. Fix the definiton of PSADBW, VPSADBW, and VPSADBWY accordingly.
4. Adjust the return type when building a DAG node of X86ISD::PSADBW type.
5. Update related tests.
Differential revision: http://reviews.llvm.org/D14897
llvm-svn: 254010
This patch detects the AVG pattern in vectorized code, which is simply
c = (a + b + 1) / 2, where a, b, and c have the same type which are vectors of
either unsigned i8 or unsigned i16. In the IR, i8/i16 will be promoted to
i32 before any arithmetic operations. The following IR shows such an example:
%1 = zext <N x i8> %a to <N x i32>
%2 = zext <N x i8> %b to <N x i32>
%3 = add nuw nsw <N x i32> %1, <i32 1 x N>
%4 = add nuw nsw <N x i32> %3, %2
%5 = lshr <N x i32> %N, <i32 1 x N>
%6 = trunc <N x i32> %5 to <N x i8>
and with this patch it will be converted to a X86ISD::AVG instruction.
The pattern recognition is done when combining instructions just before type
legalization during instruction selection. We do it here because after type
legalization, it is much more difficult to do pattern recognition based
on many instructions that are doing type conversions. Therefore, for
target-specific instructions (like X86ISD::AVG), we need to take care of type
legalization by ourselves. However, as X86ISD::AVG behaves similarly to
ISD::ADD, I am wondering if there is a way to legalize operands and result
types of X86ISD::AVG together with ISD::ADD. It seems that the current design
doesn't support this idea.
Tests are added for SSE2, AVX2, and AVX512BW and both i8 and i16 types of
variant vector sizes.
Differential revision: http://reviews.llvm.org/D14761
llvm-svn: 253952
ISERT_SUBVECTOR for i1 vectors may be done with shifts, when we insert into the lower part, or into the upper part, on into all-zero vector.
CONCAT_VECTORS uses ISERT_SUBVECTOR.
Differential Revision: http://reviews.llvm.org/D14815
llvm-svn: 253819
Summary:
Now that there is a one-to-one mapping from MachineFunction to
WinEHFuncInfo, we don't need to use a DenseMap to select the right
WinEHFuncInfo for the current funclet.
The main challenge here is that X86WinEHStatePass is an IR pass that
doesn't have access to the MachineFunction. I gave it its own
WinEHFuncInfo object that it uses to calculate state numbers, which it
then throws away. As long as nobody creates or removes EH pads between
this pass and SDAG construction, we will get the same state numbers.
The other thing X86WinEHStatePass does is to mark the EH registration
node. Instead of communicating which alloca was the registration through
WinEHFuncInfo, I added the llvm.x86.seh.ehregnode intrinsic. This
intrinsic generates no code and simply marks the alloca in use.
Reviewers: JCTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14668
llvm-svn: 253378
This patch is enabling combining UNPCKL with vector_shuffle that moves the upper
half of a vector into the lower half, into a UNPCKH instruction. For example:
t2: v16i8 = vector_shuffle<8,9,10,11,12,13,14,15,u,u,u,u,u,u,u,u> t1, undef:v16i8
t3: v16i8 = X86ISD::UNPCKL undef:v16i8, t2
will be combined to:
t3: v16i8 = X86ISD::UNPCKH undef:v16i8, t1
Differential revision: http://reviews.llvm.org/D14399
llvm-svn: 253067
Summary:
The value that the CoreCLR personality passes to a funclet for the
establisher frame may be the root function's frame or may be the parent
funclet's (mostly empty) frame in the case of nested funclets. Each
funclet stores a pointer to the root frame in its own (mostly empty)
frame, as does the root function itself. All frames allocate this slot at
the same offset, measured from the post-prolog stack pointer, so that the
same sequence can accept any ancestor as an establisher frame parameter
value, and so that a single offset can be reported to the GC, which also
looks at this slot.
This change allocate the slot when processing function entry, and records
its frame index on the WinEHFuncInfo object, then inserts the code to
set/copy it during prolog emission.
Reviewers: majnemer, AndyAyers, pgavlin, rnk
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14614
llvm-svn: 252983
Summary: Other personalities don't use this special frame slot.
Reviewers: majnemer, andrew.w.kaylor, rnk
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14580
llvm-svn: 252778
For CoreCLR on Windows, stack probes must be emitted as inline sequences that probe successive stack pages
between the current stack limit and the desired new stack pointer location. This implements support for
the inline expansion on x64.
For in-body alloca probes, expansion is done during instruction lowering. For prolog probes, a stub call
is initially emitted during prolog creation, and expanded after epilog generation, to avoid complications
that arise when introducing new machine basic blocks during prolog and epilog creation.
Added a new test case, modified an existing one to exclude non-x64 coreclr (for now).
Add test case
Fix tests
llvm-svn: 252578
The TailDuplication machine pass ran across a malformed CFG: a PHI node
referred it's predecessor's predecessor instead of it's predecessor.
This occurred because we split the edge in X86ISelLowering when we
processed the CATCHRET but forgot to do something about the PHI nodes.
This fixes PR25444.
llvm-svn: 252413
Summary:
The CLR's personality routine passes these in rdx/edx, not rax/eax.
Make getExceptionPointerRegister a virtual method parameterized by
personality function to allow making this distinction.
Similarly make getExceptionSelectorRegister a virtual method parameterized
by personality function, for symmetry.
Reviewers: pgavlin, majnemer, rnk
Subscribers: jyknight, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D14344
llvm-svn: 252383
Now that we recognize this, we can support it instead of bailing out.
That is, we can fold:
(v8i16 (shufflevector
(v8i16 (bitcast (v4i32 (build_vector X, Y, ...)))),
<1,1,...,1>))
into:
(v8i16 (vbroadcast (i16 (trunc (srl Y, 16)))))
llvm-svn: 252362
We used to incorrectly assume that the offset we're extracting from
was a multiple of the element size. So, we'd fold:
(v8i16 (shufflevector
(v8i16 (bitcast (v4i32 (build_vector X, Y, ...)))),
<1,1,...,1>))
into:
(v8i16 (vbroadcast (i16 (trunc Y))))
whereas we should have extracted the higher bits from X.
Instead, bail out if the assumption doesn't hold.
llvm-svn: 252361
This adds the EH_RESTORE x86 pseudo instr, which is responsible for
restoring the stack pointers: EBP and ESP, and ESI if stack realignment
is involved. We only need this on 32-bit x86, because on x64 the runtime
restores CSRs for us.
Previously we had to keep the CATCHRET instruction around during SEH so
that we could convince X86FrameLowering to restore our frame pointers.
Now we can split these instructions earlier.
This was confusing, because we had a return instruction which wasn't
really a return and was ultimately going to be removed by
X86FrameLowering. This change also simplifies X86FrameLowering, which
really shouldn't be building new MBBs.
No observable functional change currently, but with the new register
mask stuff in D14407, CATCHRET will become a register allocator barrier,
and our existing tests rely on us having reasonable register allocation
around SEH.
llvm-svn: 252266
We already had a test for this for 32-bit SEH catchpads, but those don't
actually create funclets. We had a bug that only appeared in funclet
prologues, where we would establish EBP and ESI as our FP and BP, and
then downstream prologue code would overwrite them.
While I was at it, I fixed Win64+funclets+stackrealign. This issue
doesn't come up as often there due to the ABI requring 16 byte stack
alignment, but now we can rest easy that AVX and WinEH will work well
together =P.
llvm-svn: 252210
This patch improves the memory folding of the inserted float element for the (V)INSERTPS instruction.
The existing implementation occurs in the DAGCombiner and relies on the narrowing of a whole vector load into a scalar load (and then converted into a vector) to (hopefully) allow folding to occur later on. Not only has this proven problematic for debug builds, it also prevents other memory folds (notably stack reloads) from happening.
This patch removes the old implementation and moves the folding code to the X86 foldMemoryOperand handler. A new private 'special case' function - foldMemoryOperandCustom - has been added to deal with memory folding of instructions that can't just use the lookup tables - (V)INSERTPS is the first of several that could be done.
It also tweaks the memory operand folding code with an additional pointer offset that allows existing memory addresses to be modified, in this case to convert the vector address to the explicit address of the scalar element that will be inserted.
Unlike the previous implementation we now set the insertion source index to zero, although this is ignored for the (V)INSERTPSrm version, anything that relied on shuffle decodes (such as unfolding of insertps loads) was incorrectly calculating the source address - I've added a test for this at insertps-unfold-load-bug.ll
Differential Revision: http://reviews.llvm.org/D13988
llvm-svn: 252074
The x86 "sitofp i64 to double" dag combine, in 32-bit mode, lowers sitofp
directly to X86ISD::FILD (or FILD_FLAG). This should not be done in soft-float mode.
llvm-svn: 252042
Optimized <8 x i32> to <8 x i16>
<4 x i64> to < 4 x i32>
<16 x i16> to <16 x i8>
All these oprtrations use now AVX512F set (KNL). Before this change it was implemented with AVX2 set.
Differential Revision: http://reviews.llvm.org/D14108
llvm-svn: 251764
This patch generalizes the zeroing of vector elements with the BLEND instructions. Currently a zero vector will only blend if the shuffled elements are correctly inline, this patch recognises when a vector input is zero (or zeroable) and modifies a local copy of the shuffle mask to support a blend. As a zeroable vector input may not be all zeroes, the zeroable vector is regenerated if necessary.
Differential Revision: http://reviews.llvm.org/D14050
llvm-svn: 251659
Android libc provides a fixed TLS slot for the unsafe stack pointer,
and this change implements direct access to that slot on AArch64 via
__builtin_thread_pointer() + offset.
This change also moves more code into TargetLowering and its
target-specific subclasses to get rid of target-specific codegen
in SafeStackPass.
This change does not touch the ARM backend because ARM lowers
builting_thread_pointer as aeabi_read_tp, which is not available
on Android.
The previous iteration of this change was reverted in r250461. This
version leaves the generic, compiler-rt based implementation in
SafeStack.cpp instead of moving it to TargetLoweringBase in order to
allow testing without a TargetMachine.
llvm-svn: 251324
When using the MCU psABI, compiler-generated library calls should pass
some parameters in-register. However, since inreg marking for x86 is currently
done by the front end, it will not be applied to backend-generated calls.
This is a workaround for PR3997, which describes a similar issue for -mregparm.
Differential Revision: http://reviews.llvm.org/D13977
llvm-svn: 251223
This patch adds support for lowering to the XOP VPROT / VPROTI vector bit rotation instructions.
This has required changes to the DAGCombiner rotation pattern matching to support vector types - so far I've only changed it to support splat vectors, but generalising this further is feasible in the future.
Differential Revision: http://reviews.llvm.org/D13851
llvm-svn: 251188
Summary:
The logic here isn't straightforward because our support for
TargetOptions::GuaranteedTailCallOpt.
Also fix a bug where we were allowing tail calls to cdecl functions from
fastcall and vectorcall functions. We were special casing thiscall and
stdcall callers rather than checking for any convention that requires
clearing stack arguments before returning.
Reviewers: hans
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14024
llvm-svn: 251137
Summary:
This ensures that BranchFolding (and similar) won't remove these blocks.
Also allow AsmPrinter::EmitBasicBlockStart to process MBBs which are
address-taken but do not have BBs that are address-taken, since otherwise
its call to getAddrLabelSymbolTableToEmit would fail an assertion on such
blocks. I audited the other callers of getAddrLabelSymbolTableToEmit
(and getAddrLabelSymbol); they all have BBs known to be address-taken
except for the call through getAddrLabelSymbol from
WinException::create32bitRef; that call is actually now unreachable, so
I've removed it and updated the signature of create32bitRef.
This fixes PR25168.
Reviewers: majnemer, andrew.w.kaylor, rnk
Subscribers: pgavlin, llvm-commits
Differential Revision: http://reviews.llvm.org/D13774
llvm-svn: 251113
Elena Demikhovsky