Commit Graph

950 Commits

Author SHA1 Message Date
Craig Topper 8dfb9627b7 [X86] Make v32i16/v64i8 legal types without avx512bw. Use custom splitting instead.
This moves v32i16/v64i8 to a model consistent with how we
treat integer types with avx1.

This does change the ABI for types vXi16/vXi8 vectors larger than
512 bits to pass in multiple zmms instead of multiple ymms. We'd
already hacked some code to make v64i8/v32i16 pass in zmm.

Cost model is still a bit of a mess. In some place I tried to
match existing behavior. But really we need to account for
splitting and concating costs. Cost model for shuffles is
especially pessimistic.

Differential Revision: https://reviews.llvm.org/D76212
2020-04-15 12:17:18 -07:00
Craig Topper d1da1b53ff [X86] Cleanup ISD::BRIND handling code in X86DAGToDAGISel::Select. NFC
-Drop llvm:: on MVT::i32
-Use getValueType instead of getSimpleValueType for an equality
check just cause its shorter and doesn't matter.
-Don't create a const SDValue & since its cheap to copy.
-Remove explicit case from MVT enum to EVT.
-Add message to assert.
2020-04-11 15:01:05 -07:00
Craig Topper 21a7d08e72 [X86] Move code that replaces ISD::VSELECT with X86ISD::BLENDV from X86DAGToDAGISel::Select to PreprocessISelDAG 2020-04-11 15:01:05 -07:00
Scott Constable 71e8021d82 [X86][NFC] Generalize the naming of "Retpoline Thunks" and related code to "Indirect Thunks"
There are applications for indirect call/branch thunks other than retpoline for Spectre v2, e.g.,

https://software.intel.com/security-software-guidance/software-guidance/load-value-injection

Therefore it makes sense to refactor X86RetpolineThunks as a more general capability.

Differential Revision: https://reviews.llvm.org/D76810
2020-04-02 21:55:13 -07:00
Guillaume Chatelet c7468c1696 [Alignment][NFC] Use Align in SelectionDAG::getMemIntrinsicNode
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, nemanjai, hiraditya, kbarton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77149
2020-04-01 09:32:05 +00:00
Craig Topper cdd1cd7120 [X86] Don't form masked instructions if the operation has an additional user.
This will cause the operation to be repeated in both a mask and another masked
or unmasked form. This can a wasted of execution resources.

Differential Revision: https://reviews.llvm.org/D60940
2020-03-27 10:44:22 -07:00
Simon Pilgrim e20e6f26fa Fix shadow variable warning. NFC. 2020-03-02 18:53:19 +00:00
Simon Pilgrim 2b624e04c7 Fix 'unsigned variable can never be negative' cppcheck warning. NFCI. 2020-03-02 18:53:18 +00:00
Craig Topper 14306ce80c [X86] Add proper MachinePointerInfo to the loads/stores created for moving data between SSE and X87 in X86DAGToDAGISel::PreprocessISelDAG 2020-02-26 14:45:37 -08:00
Craig Topper 89ba4acad6 [X86] Pass parameters into selectVectorAddr to remove dependency on X86MaskedGatherScatterSDNode.
Might be able to get rid of X86ISD::SCATTER and some uses of
X86ISD::GATHER. Which require isel to use ISD::SCATTER and
ISD::GATHER as well.
2020-02-24 23:56:34 -08:00
Craig Topper 9238dfb4d8 [X86] Remove mask output from X86 gather/scatter ISD opcodes.
Instead add it when we make the machine nodes during instruction
selections.

This makes this ISD node closer to ISD::MGATHER. Trying to see
if we remove the X86 specific ones.
2020-02-24 23:56:28 -08:00
Craig Topper 7a7146cf72 [X86] When creating X86ISD::MGATHER nodes from AVX2 gather intrinsics, cast the mask to integer type.
The gather intrinsics use a floating point mask when the result
type is FP. But we call DemandedBits on the mask assuming its an
integer type. We also use integer types when we create it from
generic IR. So add a bitcast to the intrinsic path to guarantee
the integer type.
2020-02-23 23:00:41 -08:00
Craig Topper f1b8ec3398 [X86] Use custom isel for gather/scatter instructions.
The type profile we use for the isel patterns lied about how
many operands the gather/scatter node has to skip the index
and scale operands. This allowed us to expand the baseptr
operand into base, displacement, and segment and then merge
the index and scale with them in the final instruction during
isel. This is kind of a hack that relies on isel not checking the
number of operands at all.

This commit switches to custom isel where we can manage this
directly without relying on holes in the isel checking.
2020-02-23 22:33:06 -08:00
Craig Topper dd0b18e1ec [X86] Disable load folding for X86ISD::ADD with 128 as an immediate.
It can be turned into a sub with -128 instead as long as the
carry flag isn't used.
2020-02-16 20:52:51 -08:00
Craig Topper d26f11108b [X86] Split X86ISD::CMP into an integer and FP opcode. 2020-02-16 10:10:19 -08:00
Craig Topper e5b3ae4b34 [X86] Merge two switches together to simplify some code. NFC 2020-02-15 12:55:51 -08:00
Craig Topper 3f7649799b [X86] Move combineIncDecVector logic from Select to PreprocessISelDAG.
This allows it to work properly with masked inc/dec for avx512. Those
would have a vselect as the root node so didn't get a chance to call
combineIncDecVector.

This also simplifies the logic because we don't have to manage
the topological ordering.
2020-02-15 09:59:12 -08:00
Fangrui Song 0dce409cee [AsmPrinter] De-capitalize Emit{Function,BasicBlock]* and Emit{Start,End}OfAsmFile 2020-02-13 13:22:49 -08:00
Craig Topper 656d66f5fc [X86] Use custom isel for (X86sbb_flag 0, 0) so we can use 32-bit SBB for i8/i16.
We were using MOV32r0 and an extract_subreg as an input. By using
custom isel we can move the extract_subreg to after the SBB instead
of on the input.
2020-02-09 13:19:35 -08:00
Craig Topper e1cbfecdb8 [X86] Add flag result VT to a MOV32r0 created in X86DAGToDAGISel::Select
The flag isn't used, but I believe this matches the MOV32r0 that
would be created by the table emitter. This should allow this node
to be CSEed with any others created by the table.
2020-02-09 13:19:21 -08:00
Craig Topper dd262222b4 [X86] Use MVT::i32 for the type of a MOV32r0 created in X86DAGToDAGISel::Select.
Not sure if this really matters. The VT isn't really used after
this point. At best it might affect CSE.
2020-02-09 11:57:42 -08:00
Craig Topper dbcc1392b3 [X86] Remove isel patterns that include a vselect/X86selects and a strict FP node.
A vselect+strictfp node is not equivalent to a masked operation.
The exceptions of the strictfp node are not masked by a vselect
after it so we can't match it to a masked operation.

We already had a hack in IsLegalToFold to prevent these patterns from
matching. This patch removes that hack and removes the patterns.
2020-02-09 11:45:54 -08:00
Craig Topper ae4e49868a [X86] Turn vXi1 any_extends into sign_extends in PreprocessISelDAG and remove some isel patterns.
Similar to what we do for other vector any_extends, but instead
of zero_extend we need to use sign_extend.
2020-02-06 21:32:53 -08:00
Craig Topper 4175d7e22e [X86] Custom isel floating point X86ISD::CMP on pre-CMOV targets. Eliminate ConvertCmpIfNecessary
If we don't have cmov, X87 compares write to FPSW and we need to
move the bits to EFLAGS to use as JCC/SETCC/CMOV conditions.

Previously this was done by calling ConvertCmpIfNecessary in
multiple places which would emit the extra code for the FNSTSW,
a shift, a truncate, and a SAHF instructions. Isel would then
select trunc+X86ISD::CMP to a FUCOM instruction that produces FPSW.

This patch centralizes all of the handling into a single custom
isel handler. This allows us to remove ConvertCmpIfNecessary and
a couple target specific ISD opcodes.

Differential Revision: https://reviews.llvm.org/D73863
2020-02-06 10:43:06 -08:00
Craig Topper 600f2e1c4d [X86] Remove SETB_C8r/SETB_C16r pseudo instructions. Use SETB_C32r and EXTRACT_SUBREG instead.
Only 32 and 64 bit SBB are dependency breaking instructons on some
CPUs. The 8 and 16 bit forms have to preserve upper bits of the GPR.

This patch removes the smaller forms and selects the wider form
instead. I had to do this with custom code as the tblgen generated
code glued the eflags copytoreg to the extract_subreg instead of
to the SETB pseudo.

Longer term I think we can remove X86ISD::SETCC_CARRY and use
(X86ISD::SBB zero, zero). We'll want to keep the pseudo and select
(X86ISD::SBB zero, zero) to either a MOV32r0+SBB for targets where
there is no dependency break and SETB_C32/SETB_C64 for targets
that have a dependency break. May want some way to avoid the MOV32r0
if the instruction that produced the carry flag happened to def a
register that we can use for the dependency.

I think the flag copy lowering should be using NEG instead of SUB to
handle SETB. That would avoid the MOV32r0 there. Or maybe it should
use a ADC with -1 to recreate the carry flag and keep the SETB?
That would avoid a MOVZX on the input of the SUB.

Differential Revision: https://reviews.llvm.org/D74024
2020-02-06 10:22:24 -08:00
Craig Topper d975910c50 [X86] Don't exit from foldOffsetIntoAddress if the Offset is 0, but AM.Disp is non-zero.
This is an alternate fix for the issue D73606 was trying to
solve.

The main issue here is that we bailed out of
foldOffsetIntoAddress if Offset is 0. But if we just found a
symbolic displacement and AM.Disp became non-zero
earlier, we still need to validate that AM.Disp with the symbolic
displacement.

This is my second attempt at committing this after failing
build bots previously. One thing I realized about the previous
attempt is that its possible that AM.Disp is already non-zero
and the new Offset changes it back to zero. In that case my
previous attempt failed to update AM.Disp to zero. So this patch
removes the early out for 0 and appropriately handle the 0 case
in each check so we still update AM.Disp at the end.
2020-02-01 11:26:17 -08:00
Craig Topper 007a6a155c Revert "[X86] Don't exit from foldOffsetIntoAddress if the Offset is 0, but AM.Disp is non-zero."
Possibly causing build bot failures.
2020-01-29 22:59:05 -08:00
Craig Topper 1ef8e8b414 [X86] Don't exit from foldOffsetIntoAddress if the Offset is 0, but AM.Disp is non-zero.
This is an alternate fix for the issue D73606 was trying to
solve.

The main issue here is that we bailed out of
foldOffsetIntoAddress if Offset is 0. But if we just found a
symbolic displacement and AM.Disp became non-zero
earlier, we still need to validate that AM.Disp with the symbolic
displacement.

This passes fold-add-pcrel.ll.

Differential Revision: https://reviews.llvm.org/D73608
2020-01-29 21:32:16 -08:00
Fangrui Song bc15bf66dc [X86] matchAdd: don't fold a large offset into a %rip relative address
For `ret i64 add (i64 ptrtoint (i32* @foo to i64), i64 1701208431)`,

```
X86DAGToDAGISel::matchAdd
  ...
// AM.setBaseReg(CurDAG->getRegister(X86::RIP, MVT::i64));
  if (!matchAddressRecursively(N.getOperand(0), AM, Depth+1) &&
// Try folding offset but fail; there is a symbolic displacement, so offset cannot be too large
      !matchAddressRecursively(Handle.getValue().getOperand(1), AM, Depth+1))
    return false;
  ...
  // Try again after commuting the operands.
// AM.Disp = Val; foldOffsetIntoAddress() does not know there will be a symbolic displacement
  if (!matchAddressRecursively(Handle.getValue().getOperand(1), AM, Depth+1) &&
// AM.setBaseReg(CurDAG->getRegister(X86::RIP, MVT::i64));
      !matchAddressRecursively(Handle.getValue().getOperand(0), AM, Depth+1))
// Succeeded! Produced leaq sym+disp(%rip),...
    return false;
```

`foldOffsetIntoAddress()` currently does not know there is a symbolic
displacement and can fold a large offset.

The produced `leaq sym+disp(%rip), %rax` instruction is relocated by
an R_X86_64_PC32. If disp is large and sym+disp-rip>=2**31, there
will be a relocation overflow.

This approach is still not elegant. Unfortunately the isRIPRelative
interface is a bit clumsy. I tried several solutions and eventually
picked this one.

Differential Revision: https://reviews.llvm.org/D73606
2020-01-28 22:30:52 -08:00
Craig Topper 9cc9120969 [X86] Turn FP_ROUND/STRICT_FP_ROUND into X86ISD::VFPROUND/STRICT_VFPROUND during PreprocessISelDAG to remove some duplicate isel patterns. 2020-01-11 11:06:52 -08:00
Craig Topper 81a3d987ce [X86] Remove dead code from X86DAGToDAGISel::Select that is no longer needed now that we don't mutate strict fp nodes. NFC 2020-01-11 00:27:14 -08:00
Craig Topper c2ddfa876f [X86] Simplify code by removing an unreachable condition. NFCI
For X87<->SSE conversions, the SSE type is always smaller than
the X87 type. So we can always use the smallest type for the
memory type.
2020-01-10 23:41:06 -08:00
Craig Topper 5fe5c0a60f [X86] Preserve fpexcept property when turning strict_fp_extend and strict_fp_round into stack operations.
We use the stack for X87 fp_round and for moving from SSE f32/f64 to
X87 f64/f80. Or from X87 f64/f80 to SSE f32/f64.

Note for the SSE<->X87 conversions the conversion always happens in the
X87 domain. The load/store ops in the X87 instructions are able
to signal exceptions.
2020-01-10 23:41:06 -08:00
Craig Topper 69806808b9 [X86] Use ReplaceAllUsesWith instead of ReplaceAllUsesOfValueWith to simplify some code. NFCI 2020-01-10 20:31:21 -08:00
Amara Emerson df3f4e0d77 [X86] Fix an 8 bit testb being selected when folding a volatile i32 load pattern.
Differential Revision: https://reviews.llvm.org/D71581
2020-01-06 11:46:42 -08:00
Liu, Chen3 8af492ade1 add strict float for round operation
Differential Revision: https://reviews.llvm.org/D72026
2020-01-01 20:42:12 +08:00
Fangrui Song 5edb40c022 [SelectionDAG] Disallow indirect "i" constraint
This allows us to delete InlineAsm::Constraint_i workarounds in
SelectionDAGISel::SelectInlineAsmMemoryOperand overrides and
TargetLowering::getInlineAsmMemConstraint overrides.

They were introduced to X86 in r237517 to prevent crashes for
constraints like "=*imr". They were later copied to other targets.
2019-12-29 16:50:42 -08:00
Craig Topper a21beccea2 [X86] Add STRICT versions of CVTTP2SI, CVTTP2UI, CMPM, and CMPP.
Differential Revision: https://reviews.llvm.org/D71850
2019-12-24 10:07:04 -08:00
Ulrich Weigand 0d3f782e41 [FPEnv][X86] More strict int <-> FP conversion fixes
Fix several several additional problems with the int <-> FP conversion
logic both in common code and in the X86 target. In particular:

- The STRICT_FP_TO_UINT expansion emits a floating-point compare. This
  compare can raise exceptions and therefore needs to be a strict compare.
  I've made it signaling (even though quiet would also be correct) as
  signaling is the more usual default for an LT. This code exists both
  in common code and in the X86 target.

- The STRICT_UINT_TO_FP expansion algorithm was incorrect for strict mode:
  it emitted two STRICT_SINT_TO_FP nodes and then used a select to choose one
  of the results. This can cause spurious exceptions by the STRICT_SINT_TO_FP
  that ends up not chosen. I've fixed the algorithm to use only a single
  STRICT_SINT_TO_FP instead.

- The !isStrictFPEnabled logic in DoInstructionSelection would sometimes do
  the wrong thing because it calls getOperationAction using the result VT.
  But for some opcodes, incuding [SU]INT_TO_FP, getOperationAction needs to
  be called using the operand VT.

- Remove some (obsolete) code in X86DAGToDAGISel::Select that would mutate
  STRICT_FP_TO_[SU]INT to non-strict versions unnecessarily.

Reviewed by: craig.topper

Differential Revision: https://reviews.llvm.org/D71840
2019-12-23 21:11:45 +01:00
Liu, Chen3 2f932b5729 Enable STRICT_FP_TO_SINT/UINT on X86 backend
This patch is mainly for custom lowering the vector operation.

Differential Revision: https://reviews.llvm.org/D71592
2019-12-19 14:49:13 +08:00
Craig Topper f0df4218b6 [X86] Add a simple hack to IsProfitableToFold to prevent vselect+strict fp operations from being folded into masked instructions.
We really need to update the isel patterns to prevent this, but
that requires some tablegen de-tangling. So this hack will work
for correctness in the short term.
2019-12-18 14:42:56 -08:00
Reid Kleckner 5d986953c8 [IR] Split out target specific intrinsic enums into separate headers
This has two main effects:
- Optimizes debug info size by saving 221.86 MB of obj file size in a
  Windows optimized+debug build of 'all'. This is 3.03% of 7,332.7MB of
  object file size.
- Incremental step towards decoupling target intrinsics.

The enums are still compact, so adding and removing a single
target-specific intrinsic will trigger a rebuild of all of LLVM.
Assigning distinct target id spaces is potential future work.

Part of PR34259

Reviewers: efriedma, echristo, MaskRay

Reviewed By: echristo, MaskRay

Differential Revision: https://reviews.llvm.org/D71320
2019-12-11 18:02:14 -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
Liu, Chen3 bbf7860b93 add support for strict operation fpextend/fpround/fsqrt on X86 backend
Differential Revision: https://reviews.llvm.org/D71184
2019-12-10 09:04:28 +08:00
Liu, Chen3 3041434450 Add strict fp support for instructions fadd/fsub/fmul/fdiv
Differential Revision: https://reviews.llvm.org/D68757
2019-12-06 09:44:33 +08:00
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
Craig Topper cfce8f2cfb [X86] Add strict fp support for operations of X87 instructions
This is the following patch of D68854.

This patch adds basic operations of X87 instructions, including +, -, *, / , fp extensions and fp truncations.

Patch by Chen Liu(LiuChen3)

Differential Revision: https://reviews.llvm.org/D68857
2019-11-26 10:59:41 -08:00
Craig Topper 95f44cf44a [X86] Mark vector STRICT_FADD/STRICT_FSUB as Legal and add mutation to X86ISelDAGToDAG
The prevents LegalizeVectorOps from scalarizing them. We'll need
to remove the X86 mutation code when we add isel patterns.
2019-11-21 16:19:18 -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
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