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10287 Commits

Author SHA1 Message Date
Kerry McLaughlin c0a3ab3655 Revert "[AArch64][SVE] Implement intrinsics for non-temporal loads & stores"
This reverts commit 3f5bf35f86 as it was
causing build failures in llvm-clang-x86_64-expensive-checks:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-debian/builds/392
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-ubuntu/builds/1045
2019-12-11 13:58:39 +00:00
Kerry McLaughlin 3f5bf35f86 [AArch64][SVE] Implement intrinsics for non-temporal loads & stores
Summary:
Adds the following intrinsics:
  - llvm.aarch64.sve.ldnt1
  - llvm.aarch64.sve.stnt1

This patch creates masked loads and stores with the
MONonTemporal flag set when used with the intrinsics above.

Reviewers: sdesmalen, paulwalker-arm, dancgr, mgudim, efriedma, rengolin

Reviewed By: efriedma

Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71000
2019-12-11 11:13:51 +00:00
Craig Topper d4345636e6 [LegalizeTypes] Remove manual worklist management from SoftenFloatRes_FP_EXTEND.
I think this is no longer needed. The system should take care
of legalizing any new nodes that are added. I think this might
have been needed prior to r371709 or r307053.
2019-12-10 22:33:31 -08:00
Wang, Pengfei 21bc8631fe [FPEnv][X86] Constrained FCmp intrinsics enabling on X86
Summary: This is a follow up of D69281, it enables the X86 backend support for the FP comparision.

Reviewers: uweigand, kpn, craig.topper, RKSimon, cameron.mcinally, andrew.w.kaylor

Subscribers: hiraditya, llvm-commits, annita.zhang, LuoYuanke, LiuChen3

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70582
2019-12-11 08:23:09 +08:00
Mikael Holmen 4763267eee [LegalizeTypes] Bugfixes for big-endian targets when handling BITCASTs
Summary:
This fixes PR44135.

The special case when we promote a bitcast from a vector to an int
needs special handling when we are on a big-endian target.

Prior to this fix, for the added vec_to_int we see the following in the
SelectionDAG printouts

Type-legalized selection DAG: %bb.1 'foo:bb.1'
SelectionDAG has 9 nodes:
  t0: ch = EntryToken
        t2: v8i16,ch = CopyFromReg t0, Register:v8i16 %0
      t17: v4i32 = bitcast t2
    t23: i32 = extract_vector_elt t17, Constant:i32<3>
  t8: ch,glue = CopyToReg t0, Register:i32 $r0, t23
  t9: ch = ARMISD::RET_FLAG t8, Register:i32 $r0, t8:1

and I think here the extract_vector_elt is wrong and extracts the value
from the wrong index.

The program program should return the 32 bits made up of the elements at
index 4 and 5 in the vec6 array, but with

    t23: i32 = extract_vector_elt t17, Constant:i32<3>

as far as I can tell, we will extract values that originally didn't even
exist in the vec6 vectore.

If we would instead extract the element at index 2 we would get the wanted
values.

With this fix we insert a right shift after the bitcast in
DAGTypeLegalizer::PromoteIntRes_BITCAST which then gives us

Type-legalized selection DAG: %bb.1 'vec_to_int:bb.1'
SelectionDAG has 9 nodes:
  t0: ch = EntryToken
        t2: v8i16,ch = CopyFromReg t0, Register:v8i16 %0
      t23: v4i32 = bitcast t2
    t27: i32 = extract_vector_elt t23, Constant:i32<2>
  t8: ch,glue = CopyToReg t0, Register:i32 $r0, t27
  t9: ch = ARMISD::RET_FLAG t8, Register:i32 $r0, t8:1

So now we get

    t27: i32 = extract_vector_elt t23, Constant:i32<2>

which is what we want.

Similarly, the new int_to_vec testcase exposes a bug where we cast the other
direction. Then we instead need to add a left shift before the bitcast on
big-endian targets for the bits in the input integer to end up at the exptected
place in the vector.

Reviewers: bogner, spatel, craig.topper, t.p.northover, dmgreen, efriedma, SjoerdMeijer, samparker

Reviewed By: efriedma

Subscribers: eli.friedman, bjope, kristof.beyls, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70942
2019-12-10 11:22:35 +01:00
Hiroshi Yamauchi d9ae493937 [PGO][PGSO] Instrument the code gen / target passes.
Summary:
Split off of D67120.

Add the profile guided size optimization instrumentation / queries in the code
gen or target passes. This doesn't enable the size optimizations in those passes
yet as they are currently disabled in shouldOptimizeForSize (for non-IR pass
queries).

A second try after reverted D71072.

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71149
2019-12-09 12:42:59 -08:00
Ulrich Weigand 9db13b5a7d [FPEnv] Constrained FCmp intrinsics
This adds support for constrained floating-point comparison intrinsics.

Specifically, we add:

      declare <ty2>
      @llvm.experimental.constrained.fcmp(<type> <op1>, <type> <op2>,
                                          metadata <condition code>,
                                          metadata <exception behavior>)
      declare <ty2>
      @llvm.experimental.constrained.fcmps(<type> <op1>, <type> <op2>,
                                           metadata <condition code>,
                                           metadata <exception behavior>)

The first variant implements an IEEE "quiet" comparison (i.e. we only
get an invalid FP exception if either argument is a SNaN), while the
second variant implements an IEEE "signaling" comparison (i.e. we get
an invalid FP exception if either argument is any NaN).

The condition code is implemented as a metadata string.  The same set
of predicates as for the fcmp instruction is supported (except for the
"true" and "false" predicates).

These new intrinsics are mapped by SelectionDAG codegen onto two new
ISD opcodes, ISD::STRICT_FSETCC and ISD::STRICT_FSETCCS, again
representing quiet vs. signaling comparison operations.  Otherwise
those nodes look like SETCC nodes, with an additional chain argument
and result as usual for strict FP nodes.  The patch includes support
for the common legalization operations for those nodes.

The patch also includes full SystemZ back-end support for the new
ISD nodes, mapping them to all available SystemZ instruction to
fully implement strict semantics (scalar and vector).

Differential Revision: https://reviews.llvm.org/D69281
2019-12-07 11:28:39 +01:00
Craig Topper 28b573d249 [TargetLowering] Fix another potential FPE in expandFP_TO_UINT
D53794 introduced code to perform the FP_TO_UINT expansion via FP_TO_SINT in a way that would never expose floating-point exceptions in the intermediate steps. Unfortunately, I just noticed there is still a way this can happen. As discussed in D53794, the compiler now generates this sequence:

// Sel = Src < 0x8000000000000000
// Val = select Sel, Src, Src - 0x8000000000000000
// Ofs = select Sel, 0, 0x8000000000000000
// Result = fp_to_sint(Val) ^ Ofs
The problem is with the Src - 0x8000000000000000 expression. As I mentioned in the original review, that expression can never overflow or underflow if the original value is in range for FP_TO_UINT. But I missed that we can get an Inexact exception in the case where Src is a very small positive value. (In this case the result of the sub is ignored, but that doesn't help.)

Instead, I'd suggest to use the following sequence:

// Sel = Src < 0x8000000000000000
// FltOfs = select Sel, 0, 0x8000000000000000
// IntOfs = select Sel, 0, 0x8000000000000000
// Result = fp_to_sint(Val - FltOfs) ^ IntOfs
In the case where the value is already in range of FP_TO_SINT, we now simply compute Val - 0, which now definitely cannot trap (unless Val is a NaN in which case we'd want to trap anyway).

In the case where the value is not in range of FP_TO_SINT, but still in range of FP_TO_UINT, the sub can never be inexact, as Val is between 2^(n-1) and (2^n)-1, i.e. always has the 2^(n-1) bit set, and the sub is always simply clearing that bit.

There is a slight complication in the case where Val is a constant, so we know at compile time whether Sel is true or false. In that scenario, the old code would automatically optimize the sub away, while this no longer happens with the new code. Instead, I've added extra code to check for this case and then just fall back to FP_TO_SINT directly. (This seems to catch even slightly more cases.)

Original version of the patch by Ulrich Weigand. X86 changes added by Craig Topper

Differential Revision: https://reviews.llvm.org/D67105
2019-12-06 14:11:04 -08:00
Hiroshi Yamauchi 2eb30fafa5 Revert "[PGO][PGSO] Instrument the code gen / target passes."
This reverts commit 9a0b5e1407.

This seems to break buildbots.
2019-12-06 12:17:32 -08:00
Hiroshi Yamauchi 9a0b5e1407 [PGO][PGSO] Instrument the code gen / target passes.
Summary:
Split off of D67120.

Add the profile guided size optimization instrumentation / queries in the code
gen or target passes. This doesn't enable the size optimizations in those passes
yet as they are currently disabled in shouldOptimizeForSize (for non-IR pass
queries).

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71072
2019-12-06 10:43:39 -08:00
John Brawn 984f1bb3e7 [LegalizeTypes] Add missing case for STRICT_FP_ROUND softening
This fixes a test failure in test/CodeGen/ARM/fp-intrinsics.ll.
2019-12-06 15:54:27 +00:00
Ulrich Weigand daee549b17 [FPEnv][SelectionDAG] Relax chain requirements
This patch implements the following changes:

1) SelectionDAGBuilder::visitConstrainedFPIntrinsic currently treats
each constrained intrinsic like a global barrier (e.g. a function call)
and fully serializes all pending chains. This is actually not required;
it is allowed for constrained intrinsics to be reordered w.r.t one
another or (nonvolatile) memory accesses. The MI-level scheduler already
allows for that flexibility, so it makes sense to allow it at the DAG
level as well.

This patch therefore changes the way chains for constrained intrisincs
are created, and handles them basically like load operations are handled.
This has the effect that constrained intrinsics are no longer serialized
against one another or (nonvolatile) loads. They are still serialized
against stores, but that seems hard to change with the current DAG chain
setup, and it also doesn't seem to be a big problem preventing DAG

2) The OPC_CheckFoldableChainNode check requires that each of the
intermediate nodes in a multi-node pattern match only has a single use.
This check tends to fail if those intermediate nodes are strict operations
as those have a chain output that typically indeed has another use.
However, we don't really need to consider chains here at all, since they
will all be rewritten anyway by UpdateChains later. Other parts of the
matcher therefore already ignore chains, but this hasOneUse check doesn't.

This patch replaces hasOneUse by a custom test that verifies there is no
more than one use of any non-chain output value.

In theory, this change could affect code unrelated to strict FP nodes,
but at least on SystemZ I could not find any single instance of that
happening

3) The SystemZ back-end currently does not allow matching multiply-and-
extend operations (32x32 -> 64bit or 64x64 -> 128bit FP multiply) for
strict FP operations.  This was not possible in the past due to the
problems described under 1) and 2) above.

With those issues fixed, it is now possible to fully support those
instructions in strict mode as well, and this patch does so.

Differential Revision: https://reviews.llvm.org/D70913
2019-12-06 11:02:11 +01:00
Amy Huang 9e978bb01c Add support for lowering 32-bit/64-bit pointers
Summary:
This follows a previous patch that changes the X86 datalayout to represent
mixed size pointers (32-bit sext, 32-bit zext, and 64-bit) with address spaces
(https://reviews.llvm.org/D64931)

This patch implements the address space cast lowering to the corresponding
sign extension, zero extension, or truncate instructions.

Related to https://bugs.llvm.org/show_bug.cgi?id=42359

Reviewers: rnk, craig.topper, RKSimon

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69639
2019-12-04 11:39:03 -08:00
Ulrich Weigand c3d05c1b52 [SelectionDAG] Expand nnan FMINNUM/FMAXNUM to select sequence
InstCombine may synthesize FMINNUM/FMAXNUM nodes from fcmp+select
sequences (where the fcmp is marked nnan).  Currently, if the
target does not otherwise handle these nodes, they'll get expanded
to libcalls to fmin/fmax.  However, these functions may reside in
libm, which may introduce a library dependency that was not originally
present in the source code, potentially resulting in link failures.

To fix this problem, add code to TargetLowering::expandFMINNUM_FMAXNUM
to expand FMINNUM/FMAXNUM to a compare+select sequence instead of the
libcall. This is done only if the node is marked as "nnan"; in this case,
the expansion to compare+select is always correct. This also suffices to
catch all cases where FMINNUM/FMAXNUM was synthesized as above.

Differential Revision: https://reviews.llvm.org/D70965
2019-12-04 10:32:35 +01:00
Craig Topper f586fd44e4 [FPEnv] [PowerPC] Lowering ppc_fp128 StrictFP Nodes to libcalls
This is an alternative to D64662 that shares more code between
strict and non-strict nodes. It's modeled after the implementation
that I did for softening.

Differential Revision: https://reviews.llvm.org/D70867
2019-12-03 14:11:21 -08:00
Roman Lebedev 9a20c79ddc
[NFC][KnownBits] Add getMinValue() / getMaxValue() methods
As it can be seen from accompanying cleanup, it is not unheard of
to write `~Known.Zero` meaning "what maximal value can this KnownBits
produce". But i think `~Known.Zero` isn't *that* self-explanatory,
as compared to a method with a name.

Note that not all `~Known.Zero` places were cleaned up,
only those where this arguably improves things.
2019-12-03 20:04:51 +03:00
Amaury Séchet b4980f7781 [SelectionDAG] Reoder ViewXXXDAGs declarations to match execution order. NFC 2019-12-03 16:26:12 +01:00
Craig Topper 039664db87 [LegalizeDAG] Return true from ExpandNode for some nodes that don't have expand support.
These nodes have a FIXME that they only get here because a Custom
handler returned SDValue() instead of the original Op.

Even though we aren't expanding them, we should return true here to
prevent ConvertNodeToLibcall from also trying to process them until
the FIXME has been addressed.

I'm hoping to add checking to ConvertNodeToLibcall to make sure
we don't give it nodes it doesn't have support for.
2019-12-02 23:39:20 -08:00
Craig Topper f92000187e [LegalizeDAG] When expanding vector SRA/SRL/SHL add the new BUILD_VECTOR to the Results vector instead of just calling ReplaceNode
The code that processes the Results vector also calls ReplaceNode
and makes ExpandNode return true.

If we don't add it to the Results node, we end up returning false
from ExpandNode. This causes ConvertNodeToLibcall to be called next.
But ConvertNodeToLibcall doesn't do anything for shifts so they
just pass through unmodified. Except for printing a debug message.

Ultimately, I'd like to add more checks to ExpandNode and
ConvertNodeToLibcall to make sure we don't have nodes marked as
Expand that don't have any Expand or libcall handling.
2019-12-02 23:07:39 -08:00
Amaury Séchet c594d14d40 [DAGCombine] Factor oplist operations. NFC 2019-12-02 19:12:03 +01:00
Amaury Séchet d8d5106225 [SelectionDAG] Reduce assumptions made about levels. NFC 2019-12-02 17:43:13 +01:00
Craig Topper 2f3e8cb313 [LegalizeTypes] Add strict FP support to SoftenFloatRes_FP_ROUND. Fix mistake in SoftenFloatRes_FP_EXTEND.
These will be needed for ARM fp-instrinsics.ll which is currently
XFAILed.

One of the getOperand calls in SoftenFloatRes_FP_EXTEND was not
taking strict FP into account. It only affected the call
to setTypeListBeforeSoften which only has an effect on some targets.
2019-11-28 15:32:09 -08:00
Craig Topper 68ddf434c0 [LegalizeTypes] In SoftenFloatRes_FNEG, always generate integer arithmetic, never fall back to using fsub.
We would previously fallback if the type wasn't f32/f64/f128. But
I don't think any of the other floating point types ever go through
the softening code anyway. So this code is dead.
2019-11-28 15:30:34 -08:00
Craig Topper 2485fa7739 [LegalizeTypes] Use SoftenFloatRes_Unary in SoftenFloatRes_FCBRT to reduce code.
We don't have a STRICT_CBRT ISD opcode, but we can still
use SoftenFloatRes_Unary to simplify some code.
2019-11-28 15:30:34 -08:00
Amaury Séchet ca818f4550 [DAGCombiner] Peek through vector concats when trying to combine shuffles.
Summary: This combine showed up as needed when exploring the regression when processing the DAG in topological order.

Reviewers: craig.topper, efriedma, RKSimon, lebedev.ri

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68195
2019-11-28 23:57:29 +01:00
Craig Topper 735f4793f1 [LegalizeTypes] Remove dead code related to softening f16 which we no longer do.
f16 is promoted to f32 if it is not legal on the target.

Found while reviewing what else needed to be done for strict FP in
the softening code.
2019-11-27 22:10:30 -08:00
Craig Topper ed521fef03 [LegalTypes][X86] Add SoftenFloatOperand support for STRICT_FP_TO_SINT/STRICT_FP_TO_UINT. 2019-11-27 21:16:13 -08:00
Craig Topper 1727c4f1a2 [LegalizeTypes][X86] Add ExpandIntegerResult support for STRICT_FP_TO_SINT/STRICT_FP_TO_UINT. 2019-11-27 18:41:45 -08:00
Craig Topper ebfff46c8d [LegalizeTypes][FPEnv][X86] Add initial support for softening strict fp nodes
This is based on what's required for softening fp128 operations on 32-bit X86 assuming f32/f64/f80 are legal. So there could be some things missing.

Differential Revision: https://reviews.llvm.org/D70654
2019-11-27 10:50:10 -08:00
Craig Topper 350565dbc0 [LegalizeTypes] Add SoftenFloatOp_Unary to reduce some duplication for softening LRINT/LLRINT/LROUND/LLROUND
Summary: This will be enhanced in a follow up to add strict fp support

Reviewers: efriedma

Reviewed By: efriedma

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70751
2019-11-26 17:37:51 -08:00
Craig Topper 9b08366f57 [LegalizeTypes] Add SoftenFloatRes_Unary and SoftenFloatRes_Binary functions to factor repeated patterns out of many of the SoftenFloatRes_* functions
This has been factored out of D70654 which will add strict FP support to these functions. By making the helpers we avoid repeating even more code.

Differential Revision: https://reviews.llvm.org/D70736
2019-11-26 12:52:17 -08:00
Craig Topper ee3b375b4c [LegalizeDAG] Use getOperationAction instead of getStrictFPOperationAction for STRICT_LRINT/LROUND/LLRINT/LLROUND. 2019-11-26 11:57:45 -08:00
David Green b5315ae8ff [Codegen][ARM] Add addressing modes from masked loads and stores
MVE has a basic symmetry between it's normal loads/store operations and
the masked variants. This means that masked loads and stores can use
pre-inc and post-inc addressing modes, just like the standard loads and
stores already do.

To enable that, this patch adds all the relevant infrastructure for
treating masked loads/stores addressing modes in the same way as normal
loads/stores.

This involves:
- Adding an AddressingMode to MaskedLoadStoreSDNode, along with an extra
   Offset operand that is added after the PtrBase.
- Extending the IndexedModeActions from 8bits to 16bits to store the
   legality of masked operations as well as normal ones. This array is
   fairly small, so doubling the size still won't make it very large.
   Offset masked loads can then be controlled with
   setIndexedMaskedLoadAction, similar to standard loads.
- The same methods that combine to indexed loads, such as
   CombineToPostIndexedLoadStore, are adjusted to handle masked loads in
   the same way.
- The ARM backend is then adjusted to make use of these indexed masked
   loads/stores.
- The X86 backend is adjusted to hopefully be no functional changes.

Differential Revision: https://reviews.llvm.org/D70176
2019-11-26 16:21:01 +00:00
Luís Marques 6fd4c42fa8 [LegalizeTypes][RISCV] Soften FCOPYSIGN operand
Summary: Adds support for softening FCOPYSIGN operands.
Adds RISC-V tests that exercise the new softening code.

Reviewers: asb, lenary, efriedma
Reviewed By: efriedma
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70679
2019-11-26 15:22:55 +00:00
Craig Topper 3dc7c5f7d8 [LegalizeTypes] Remove code to create ISD::FP_TO_FP16 from SoftenFloatRes_FTRUNC.
There seems to have been a misunderstanding of what ISD::FTRUNC
represents. ISD::FTRUNC is equivalent to llvm.trunc which takes
a floating point value, truncates it without changing the size
of the value and returns it.

Despite its similar name, its different than the fptrunc instruction
in IR which changes a floating point value to a smaller floating
point value. fptrunc is represented by ISD::FP_ROUND in SelectionDAG.

Since the ISD::FP_TO_FP16 node takes a floating point value and
converts it to f16 its more similar to ISD::FP_ROUND. In fact there
is identical code to what is being removed here in SoftenFloatRes_FP_ROUND.

I assume this bug was never encountered because it would require
f16 to be legalized by softening rather than the default of
promoting.
2019-11-25 18:18:40 -08:00
Sanjay Patel 214683f3b2 [DAGCombiner] avoid crash on out-of-bounds insert index (PR44139)
We already have this simplification at node-creation-time, but
the test from:
https://bugs.llvm.org/show_bug.cgi?id=44139
...shows that we can combine our way to an assert/crash too.
2019-11-25 16:24:06 -05:00
Craig Topper d6ec6e4bf6 [TargetLowering] Merge ExpandChainLibCall with makeLibCall
I need to be able to drop an operand for STRICT_FP_ROUND handling on X86. Merging these functions gives me the ArrayRef interface that passes the return type, operands, and debugloc instead of the Node.

Differential Revision: https://reviews.llvm.org/D70503
2019-11-25 10:52:49 -08:00
Clement Courbet cb15ba84fe Reland "[DAGCombiner] Allow zextended load combines."
Check that the generated type is simple.
2019-11-22 14:47:18 +01:00
Roman Lebedev 96cf5c8d47
[Codegen] TargetLowering::prepareUREMEqFold(): `x u% C1 ==/!= C2` (PR35479)
Summary:
The current lowering is:
```
Name: (X % C1) == C2 -> X * C3 <= C4 || false
Pre: (C2 == 0 || C1 u<= C2) && (C1 u>> countTrailingZeros(C1)) * C3 == 1
%zz = and i8 C3, 0 ; trick alive into making C3 avaliable in precondition
%o0 = urem i8 %x, C1
%r = icmp eq i8 %o0, C2
  =>
%zz = and i8 C3, 0 ; and silence it from complaining about said reg
%C4 = -1 /u C1
%n0 = mul i8 %x, C3
%n1 = lshr i8 %n0, countTrailingZeros(C1) ; rotate right
%n2 = shl i8 %n0, ((8-countTrailingZeros(C1)) %u 8) ; rotate right
%n3 = or i8 %n1, %n2 ; rotate right
%is_tautologically_false = icmp ule i8 C1, C2
%C4_fixed = select i1 %is_tautologically_false, i8 -1, i8 %C4
%res = icmp ule i8 %n3, %C4_fixed
%r = xor i1 %res, %is_tautologically_false
```
https://rise4fun.com/Alive/2xC
https://rise4fun.com/Alive/jpb5

However, we can support non-tautological cases `C1 u> C2` too.
Said handling consists of two parts:
* `C2 u<= (-1 %u C1)`. It just works. We only have to change `(X % C1) == C2` into `((X - C2) % C1) == 0`
```
Name: (X % C1) == C2 -> (X - C2) * C3 <= C4   iff C2 u<= (-1 %u C1)
Pre: (C1 u>> countTrailingZeros(C1)) * C3 == 1 && C2 u<= (-1 %u C1)
%zz = and i8 C3, 0 ; trick alive into making C3 avaliable in precondition
%o0 = urem i8 %x, C1
%r = icmp eq i8 %o0, C2
  =>
%zz = and i8 C3, 0 ; and silence it from complaining about said reg
%C4 = (-1 /u C1)
%n0 = sub i8 %x, C2
%n1 = mul i8 %n0, C3
%n2 = lshr i8 %n1, countTrailingZeros(C1) ; rotate right
%n3 = shl i8 %n1, ((8-countTrailingZeros(C1)) %u 8) ; rotate right
%n4 = or i8 %n2, %n3 ; rotate right
%is_tautologically_false = icmp ule i8 C1, C2
%C4_fixed = select i1 %is_tautologically_false, i8 -1, i8 %C4
%res = icmp ule i8 %n4, %C4_fixed
%r = xor i1 %res, %is_tautologically_false
```
https://rise4fun.com/Alive/m4P
https://rise4fun.com/Alive/SKrx
* `C2 u> (-1 %u C1)`. We also have to change `(X % C1) == C2` into `((X - C2) % C1) == 0`,
  and we have to decrement C4:
```
Name: (X % C1) == C2 -> (X - C2) * C3 <= C4   iff C2 u> (-1 %u C1)
Pre: (C1 u>> countTrailingZeros(C1)) * C3 == 1 && C2 u> (-1 %u C1)
%zz = and i8 C3, 0 ; trick alive into making C3 avaliable in precondition
%o0 = urem i8 %x, C1
%r = icmp eq i8 %o0, C2
  =>
%zz = and i8 C3, 0 ; and silence it from complaining about said reg
%C4 = (-1 /u C1)-1
%n0 = sub i8 %x, C2
%n1 = mul i8 %n0, C3
%n2 = lshr i8 %n1, countTrailingZeros(C1) ; rotate right
%n3 = shl i8 %n1, ((8-countTrailingZeros(C1)) %u 8) ; rotate right
%n4 = or i8 %n2, %n3 ; rotate right
%is_tautologically_false = icmp ule i8 C1, C2
%C4_fixed = select i1 %is_tautologically_false, i8 -1, i8 %C4
%res = icmp ule i8 %n4, %C4_fixed
%r = xor i1 %res, %is_tautologically_false
```
https://rise4fun.com/Alive/d40
https://rise4fun.com/Alive/8cF

I believe this concludes `x u% C1 ==/!= C2` lowering.
In fact, clang is may now be better in this regard than gcc:
as it can be seen from `@t32_6_4` test, we do lower `x % 6 == 4`
via this pattern, while gcc does not: https://godbolt.org/z/XNU2z9
And all the general alive proofs say this is legal.
And manual checking agrees: https://rise4fun.com/Alive/WA2

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=35479 | PR35479 ]].

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: nick, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70053
2019-11-22 15:22:42 +03:00
Roman Lebedev 3f46022e33
[Codegen] TargetLowering::prepareUREMEqFold(): `x u% C1 ==/!= C2` with tautological C1 u<= C2 (PR35479)
Summary:
This is a preparatory cleanup before i add more
of this fold to deal with comparisons with non-zero.

In essence, the current lowering is:
```
Name: (X % C1) == 0 -> X * C3 <= C4
Pre: (C1 u>> countTrailingZeros(C1)) * C3 == 1
%zz = and i8 C3, 0 ; trick alive into making C3 avaliable in precondition
%o0 = urem i8 %x, C1
%r = icmp eq i8 %o0, 0
  =>
%zz = and i8 C3, 0 ; and silence it from complaining about said reg
%C4 = -1 /u C1
%n0 = mul i8 %x, C3
%n1 = lshr i8 %n0, countTrailingZeros(C1) ; rotate right
%n2 = shl i8 %n0, ((8-countTrailingZeros(C1)) %u 8) ; rotate right
%n3 = or i8 %n1, %n2 ; rotate right
%r = icmp ule i8 %n3, %C4
```
https://rise4fun.com/Alive/oqd

It kinda just works, really no weird edge-cases.
But it isn't all that great for when comparing with non-zero.
In particular, given `(X % C1) == C2`, there will be problems
in the always-false tautological case where `C2 u>= C1`:
https://rise4fun.com/Alive/pH3

That case is tautological, always-false:
```
Name: (X % Y) u>= Y
%o0 = urem i8 %x, %y
%r = icmp uge i8 %o0, %y
  =>
%r = false
```
https://rise4fun.com/Alive/ofu

While we can't/shouldn't get such tautological case normally,
we do deal with non-splat vectors, so unless we want to give up
in this case, we need to fixup/short-circuit such lanes.

There are two lowering variants:
1. We can blend between whatever computed result and the correct tautological result
```
Name: (X % C1) == C2 -> X * C3 <= C4 || false
Pre: (C2 == 0 || C1 u<= C2) && (C1 u>> countTrailingZeros(C1)) * C3 == 1
%zz = and i8 C3, 0 ; trick alive into making C3 avaliable in precondition
%o0 = urem i8 %x, C1
%r = icmp eq i8 %o0, C2
  =>
%zz = and i8 C3, 0 ; and silence it from complaining about said reg
%C4 = -1 /u C1
%n0 = mul i8 %x, C3
%n1 = lshr i8 %n0, countTrailingZeros(C1) ; rotate right
%n2 = shl i8 %n0, ((8-countTrailingZeros(C1)) %u 8) ; rotate right
%n3 = or i8 %n1, %n2 ; rotate right
%is_tautologically_false = icmp ule i8 C1, C2
%res = icmp ule i8 %n3, %C4
%r = select i1 %is_tautologically_false, i1 0, i1 %res
```
https://rise4fun.com/Alive/PjT5
https://rise4fun.com/Alive/1KV

2. We can invert the comparison result
```
Name: (X % C1) == C2 -> X * C3 <= C4 || false
Pre: (C2 == 0 || C1 u<= C2) && (C1 u>> countTrailingZeros(C1)) * C3 == 1
%zz = and i8 C3, 0 ; trick alive into making C3 avaliable in precondition
%o0 = urem i8 %x, C1
%r = icmp eq i8 %o0, C2
  =>
%zz = and i8 C3, 0 ; and silence it from complaining about said reg
%C4 = -1 /u C1
%n0 = mul i8 %x, C3
%n1 = lshr i8 %n0, countTrailingZeros(C1) ; rotate right
%n2 = shl i8 %n0, ((8-countTrailingZeros(C1)) %u 8) ; rotate right
%n3 = or i8 %n1, %n2 ; rotate right
%is_tautologically_false = icmp ule i8 C1, C2
%C4_fixed = select i1 %is_tautologically_false, i8 -1, i8 %C4
%res = icmp ule i8 %n3, %C4_fixed
%r = xor i1 %res, %is_tautologically_false
```
https://rise4fun.com/Alive/2xC
https://rise4fun.com/Alive/jpb5

3. We can expand into `and`/`or`:
https://rise4fun.com/Alive/WGn
https://rise4fun.com/Alive/lcb5

Blend-one is likely better since we avoid having to load the
replacement from constant pool. `xor` is second best since
it's still pretty general. I'm not adding `and`/`or` variants.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: nick, hiraditya, xbolva00, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70051
2019-11-22 15:16:03 +03:00
Clement Courbet 88e205525c Revert "[DAGCombiner] Allow zextended load combines."
Breaks some bots.
2019-11-22 09:01:08 +01:00
Clement Courbet 036790f988 [DAGCombiner] Allow zextended load combines.
Summary: or(zext(load8(base)), zext(load8(base+1)) -> zext(load16 base)

Reviewers: apilipenko, RKSimon

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70487
2019-11-22 08:40:19 +01:00
Pengfei Wang 22a0edd070 [FPEnv] Add an option to disable strict float node mutating to an normal
float node

This patch add an option 'disable-strictnode-mutation' to prevent strict
node mutating to an normal node.
So we can make sure that the patch which sets strict-node as legal works
correctly.

Patch by Chen Liu(LiuChen3)

Differential Revision: https://reviews.llvm.org/D70226
2019-11-21 18:07:11 -08:00
Craig Topper 7696b99258 [LegalizeDAG][X86] Add support for turning STRICT_FADD/SUB/MUL/DIV into libcalls. Use it for fp128 on x86-64.
This requires a minor hack for f32/f64 strict fadd/fsub to avoid
turning those into libcalls.
2019-11-21 16:19:25 -08:00
Hiroshi Yamauchi 52e377497d [PGO][PGSO] DAG.shouldOptForSize part.
Summary:
(Split of off D67120)

SelectionDAG::shouldOptForSize changes for profile guided size optimization.

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70095
2019-11-21 14:16:00 -08:00
Tom Stellard ab411801b8 [cmake] Explicitly mark libraries defined in lib/ as "Component Libraries"
Summary:
Most libraries are defined in the lib/ directory but there are also a
few libraries defined in tools/ e.g. libLLVM, libLTO.  I'm defining
"Component Libraries" as libraries defined in lib/ that may be included in
libLLVM.so.  Explicitly marking the libraries in lib/ as component
libraries allows us to remove some fragile checks that attempt to
differentiate between lib/ libraries and tools/ libraires:

1. In tools/llvm-shlib, because
llvm_map_components_to_libnames(LIB_NAMES "all") returned a list of
all libraries defined in the whole project, there was custom code
needed to filter out libraries defined in tools/, none of which should
be included in libLLVM.so.  This code assumed that any library
defined as static was from lib/ and everything else should be
excluded.

With this change, llvm_map_components_to_libnames(LIB_NAMES, "all")
only returns libraries that have been added to the LLVM_COMPONENT_LIBS
global cmake property, so this custom filtering logic can be removed.
Doing this also fixes the build with BUILD_SHARED_LIBS=ON
and LLVM_BUILD_LLVM_DYLIB=ON.

2. There was some code in llvm_add_library that assumed that
libraries defined in lib/ would not have LLVM_LINK_COMPONENTS or
ARG_LINK_COMPONENTS set.  This is only true because libraries
defined lib lib/ use LLVMBuild.txt and don't set these values.
This code has been fixed now to check if the library has been
explicitly marked as a component library, which should now make it
easier to remove LLVMBuild at some point in the future.

I have tested this patch on Windows, MacOS and Linux with release builds
and the following combinations of CMake options:

- "" (No options)
- -DLLVM_BUILD_LLVM_DYLIB=ON
- -DLLVM_LINK_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_BUILD_LLVM_DYLIB=ON
- -DBUILD_SHARED_LIBS=ON -DLLVM_LINK_LLVM_DYLIB=ON

Reviewers: beanz, smeenai, compnerd, phosek

Reviewed By: beanz

Subscribers: wuzish, jholewinski, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, mgorny, mehdi_amini, sbc100, jgravelle-google, hiraditya, aheejin, fedor.sergeev, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, steven_wu, rogfer01, MartinMosbeck, brucehoult, the_o, dexonsmith, PkmX, jocewei, jsji, dang, Jim, lenary, s.egerton, pzheng, sameer.abuasal, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70179
2019-11-21 10:48:08 -08:00
Clement Courbet 252567377c [DAGCombine][NFC] Use ArrayRef and correctly size SmallVectors.
In preparation for D70487.
2019-11-21 08:53:37 +01:00
Craig Topper c9e8e808cf [SelectionDAG][X86] Mutate strictFP nodes to non-strict in DoInstructionSelection when the node is marked Expand rather than when it is not Legal.
This allows operations that are marked Custom, but have some type
combinations that are legal to get past this code.

Add custom mutation code to X86's Select function for the nodes
that don't have isel patterns yet.
2019-11-20 10:36:02 -08:00
David Zarzycki 257acbf6ae
[SelectionDAG] Combine U{ADD,SUB}O diamonds into {ADD,SUB}CARRY
Summary:
Convert (uaddo (uaddo x, y), carryIn) into addcarry x, y, carryIn if-and-only-if the carry flags of the first two uaddo are merged via OR or XOR.

Work remaining: match ADD, etc.

Reviewers: craig.topper, RKSimon, spatel, niravd, jonpa, uweigand, deadalnix, nikic, lebedev.ri, dmgreen, chfast

Reviewed By: lebedev.ri

Subscribers: chfast, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70079
2019-11-20 16:25:42 +02:00
Serge Pavlov ea8678d1c7 Move floating point related entities to namespace level
This is recommit of commit e6584b2b7b, which was reverted in
30e7ee3c4b together with af57dbf12e.
Original message is below.

Enumerations that describe rounding mode and exception behavior were
defined inside ConstrainedFPIntrinsic. It makes sense to use the same
definitions to represent the same properties in other cases, not only
in constrained intrinsics. It was however inconvenient as required to
include constrained intrinsics definitions even if they were not needed.
Also using long scope prefix reduced readability.

This change moves these definitioins to the namespace llvm::fp.
No functional changes.

Differential Revision: https://reviews.llvm.org/D69552
2019-11-20 19:05:46 +07:00