1873 Commits

Author SHA1 Message Date
Simon Pilgrim
4864971eb2 [DAGCombiner] Add vector demanded elements support to computeKnownBitsForTargetNode
Follow up to D25691, this sets up the plumbing necessary to support vector demanded elements support in known bits calculations in target nodes.

Differential Revision: https://reviews.llvm.org/D31249

llvm-svn: 299201
2017-03-31 11:24:16 +00:00
Ahmed Bougacha
6e6c156614 [CodeGen] Pass SDAG an ORE, and replace FastISel stats with remarks.
In the long-term, we want to replace statistics with something
finer-grained that lets us gather per-function data.
Remarks are that replacement.

Create an ORE instance in SelectionDAGISel, and pass it to
SelectionDAG.

SelectionDAG was used so that we can emit remarks from all
SelectionDAG-related code, including TargetLowering and DAGCombiner.
This isn't used in the current patch but Adam tells me he's interested
for the fp-contract combines.

Use the ORE instance to emit FastISel failures as remarks (instead of
the mix of dbgs() dumps and statistics that we currently have).

Eventually, we want to have an API that tells us whether remarks are
enabled (http://llvm.org/PR32352) so that we don't emit expensive
remarks (in this case, dumping IR) when it's not needed.  For now, use
'isEnabled' as a crude replacement.

This does mean that the replacement for '-fast-isel-verbose' is now
'-pass-remarks-missed=isel'.  Additionally, clang users also need to
enable remark diagnostics, using '-Rpass-missed=isel'.

This also removes '-fast-isel-verbose2': there are no static statistics
that we want to only enable in asserts builds, so we can always use
the remarks regardless of the build type.

Differential Revision: https://reviews.llvm.org/D31405

llvm-svn: 299093
2017-03-30 17:49:58 +00:00
Sanjay Patel
9a091cc4ac [DAG] fix formatting; NFC
llvm-svn: 298950
2017-03-28 22:25:25 +00:00
Simon Pilgrim
5fca869036 Apply clang-format as commented in D31311. NFCI.
llvm-svn: 298751
2017-03-24 23:47:41 +00:00
Simon Pilgrim
8e3c60968e Fix constant folding of fp2int to large integers
We make the assumption in most of our constant folding code that a fp2int will target an integer of 128-bits or less, calling the APFloat::convertToInteger with only uint64_t[2] of raw bits for the result.

Fuzz testing (PR24662) showed that we don't handle other cases at all, resulting in stack overflows and all sorts of crashes.

This patch uses the APSInt version of APFloat::convertToInteger instead to better handle such cases.

Differential Revision: https://reviews.llvm.org/D31074

llvm-svn: 298226
2017-03-19 16:50:25 +00:00
Nirav Dave
88936693e4 Make library calls sensitive to regparm module flag (Fixes PR3997).
Reviewers: mkuper, rnk

Subscribers: mehdi_amini, jyknight, aemerson, llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D27050

llvm-svn: 298179
2017-03-18 00:44:07 +00:00
Eli Friedman
c0e6994e99 [SelectionDAG] Remove redundant stores more aggressively.
Handle TokenFactors more aggressively in
SDValue::reachesChainWithoutSideEffects.  This isn't really a
very effective change anymore because of other changes to
chain handling, but it's a cheap check, and the expanded
comments are still useful.

It might be possible to loosen the hasOneUse() requirement with a
deeper analysis, but a naive implementation of that check would be
expensive.

Differential Revision: https://reviews.llvm.org/D29845

llvm-svn: 298156
2017-03-17 22:15:50 +00:00
Simon Pilgrim
52d0e4b51c [SelectionDAG] Add SelectionDAG.computeKnownBits test support for ISD::ABS
llvm-svn: 298108
2017-03-17 17:45:36 +00:00
Craig Topper
079e16bb3c [CodeGen] Use APInt::setLowBits/setHighBits/setBitsFrom in more places
This patch replaces ORs with getHighBits/getLowBits etc. with setLowBits/setHighBits/setBitsFrom.

In a few of the places we weren't ORing, but the KnownZero/KnownOne vectors were already initialized to zero. We exploit this in most places already there were just some that were inconsistent.

Differential Revision: https://reviews.llvm.org/D30965

llvm-svn: 297860
2017-03-15 16:53:53 +00:00
Simon Pilgrim
1e8a4166d4 [SelectionDAG] Support BUILD_VECTOR implicit truncation in SelectionDAG::ComputeNumSignBits (PR32273)
llvm-svn: 297852
2017-03-15 16:22:24 +00:00
Nuno Lopes
482fb76dae fix gcc -Wmisleading-indentation [NFC]
llvm-svn: 297816
2017-03-15 09:33:33 +00:00
Simon Pilgrim
553a3a2a4a [SelectionDAG] Add a signed integer absolute ISD node
Reduced version of D26357 - based on the discussion on llvm-dev about canonicalization of UMIN/UMAX/SMIN/SMAX as well as ABS I've reduced that patch to just the ABS ISD node (with x86/sse support) to improve basic combines and lowering.

ARM/AArch64, Hexagon, PowerPC and NVPTX all have similar instructions allowing us to make this a generic opcode and move away from the hard coded tablegen patterns which makes it tricky to match more complex patterns.

At the moment this patch doesn't attempt legalization as we only create an ABS node if its legal/custom.

Differential Revision: https://reviews.llvm.org/D29639

llvm-svn: 297780
2017-03-14 21:26:58 +00:00
Sanjay Patel
de78e1aaa3 [DAG] vector div/rem with any zero element in divisor is undef
This is the backend counterpart to:
https://reviews.llvm.org/rL297390
https://reviews.llvm.org/rL297409
and follow-up to:
https://reviews.llvm.org/rL297384

It surprised me that we need to duplicate the check in FoldConstantArithmetic and FoldConstantVectorArithmetic, 
but one or the other doesn't catch all of the test cases. There is an existing code comment about merging those 
someday.

Differential Revision: https://reviews.llvm.org/D30826

llvm-svn: 297762
2017-03-14 18:06:28 +00:00
Amaury Sechet
1085d274e8 Use setBits in SelectionDAG
Summary: As per title.

Reviewers: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30836

llvm-svn: 297559
2017-03-11 11:24:03 +00:00
Simon Pilgrim
0f8a406c91 [SelectionDAG] Add support for BUILD_VECTOR to ComputeNumSignBits
llvm-svn: 297492
2017-03-10 18:36:46 +00:00
Amaury Sechet
0df4fc2c35 [SelectionDAG] Make SelectionDAG aware of the known bits in USUBO and SSUBO and SUBC.
Summary:
Depends on D30379

This improves the state of things for the sub class of operation.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30436

llvm-svn: 297482
2017-03-10 17:26:44 +00:00
Amaury Sechet
5587e02e22 [SelectionDAG] Make SelectionDAG aware of the known bits in UADDO and SADDO.
Summary: As per title. This is extracted from D29872 and I threw SADDO in.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30379

llvm-svn: 297479
2017-03-10 17:06:52 +00:00
Simon Pilgrim
9d9d7803a0 [APInt] Add APInt::insertBits() method to insert an APInt into a larger APInt
We currently have to insert bits via a temporary variable of the same size as the target with various shift/mask stages, resulting in further temporary variables, all of which require the allocation of memory for large APInts (MaskSizeInBits > 64).

This is another of the compile time issues identified in PR32037 (see also D30265).

This patch adds the APInt::insertBits() helper method which avoids the temporary memory allocation and masks/inserts the raw bits directly into the target.

Differential Revision: https://reviews.llvm.org/D30780

llvm-svn: 297458
2017-03-10 13:44:32 +00:00
Sanjay Patel
9d801bd5a1 [DAG] recognize div/rem by 0 as undef before trying constant folding
As discussed in the review thread for rL297026, this is actually 2 changes that 
would independently fix all of the test cases in the patch:

1. Return undef in FoldConstantArithmetic for div/rem by 0.
2. Move basic undef simplifications for div/rem (simplifyDivRem()) before 
   foldBinopIntoSelect() as a matter of efficiency.

I will handle the case of vectors with any zero element as a follow-up. That change
is the DAG sibling for D30665 + adding a check of vector elements to FoldConstantVectorArithmetic().

I'm deleting the test for PR30693 because it does not test for the actual bug any more
(dangers of using bugpoint).

Differential Revision:
https://reviews.llvm.org/D30741

llvm-svn: 297384
2017-03-09 15:02:25 +00:00
Simon Pilgrim
84ae30b32d [X86][SSE] Lower 128-bit vectors to SIGN/ZERO_EXTEND_VECTOR_IN_REG ops
As described on PR31712, we miss a variety of legalization combines because we lower these to X86ISD::VSEXT/VZEXT despite them having the same functionality. This patch makes 128-bit (SSE41) SIGN/ZERO_EXTEND_VECTOR_IN_REG ops legal, adds the necessary tablegen plumbing and uses a helper 'getExtendInVec' to decide when to use SIGN/ZERO_EXTEND_VECTOR_IN_REG or VSEXT/VZEXT.

We're missing a couple of shuffle combines that will be added in a future patch for review.

Later patches can then support the AVX2 cases as a mixture of SIGN/ZERO_EXTEND and SIGN/ZERO_EXTEND_VECTOR_IN_REG, and then finally deal with the AVX512 cases.

Differential Revision: https://reviews.llvm.org/D30549

llvm-svn: 296985
2017-03-05 09:57:20 +00:00
Simon Pilgrim
f1e7abde01 Use APInt::setBits instead of OR'ing in a separate APInt::getBitsSet call
llvm-svn: 296886
2017-03-03 17:03:52 +00:00
Amaury Sechet
c49fa55b23 [DAGCombiner] mulhi + 1 never overflow.
Summary:
This can be used to optimize large multiplications after legalization.

Depends on D29565

Reviewers: mkuper, spatel, RKSimon, zvi, bkramer, aaboud, craig.topper

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29587

llvm-svn: 296711
2017-03-01 23:44:17 +00:00
Simon Pilgrim
91218fd943 [DAGCombine] Allow vector constant folding of any value type before type legalization
The patch comes in 2 parts:

1 - it makes use of the SelectionDAG::NewNodesMustHaveLegalTypes flag to tell when it can safely constant fold illegal types.

2 - it correctly resets SelectionDAG::NewNodesMustHaveLegalTypes at the start of each call to SelectionDAGISel::CodeGenAndEmitDAG so all the pre-legalization stages can make use of it - not just the first basic block that gets handled.

Fix for PR30760

Differential Revision: https://reviews.llvm.org/D29568

llvm-svn: 294749
2017-02-10 14:37:25 +00:00
Amaury Sechet
d379414d1c Add ADDC to SelectionDAG::computeKnownBits and ComputeNumSignBits.
Summary: As per title.

Reviewers: bkramer, sunfish, lattner, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29521

llvm-svn: 294188
2017-02-06 14:59:06 +00:00
Amaury Sechet
cc55016d9e [DAGCombiner] Make DAGCombiner smarter about overflow
Summary: Leverage it to transform addc into add.

Reviewers: mkuper, spatel, RKSimon, zvi

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29524

llvm-svn: 294187
2017-02-06 14:54:49 +00:00
Simon Pilgrim
54efd46261 [X86][SSE] Combine shuffle nodes with multiple uses if all the users are being combined.
Currently we only combine shuffle nodes if they have a single user to prevent us from causing code bloat by splitting the shuffles into several different combines.

We don't take into account that in some cases we will already have combined all the users during recursively calling up the shuffle tree.

This patch keeps a list of all the shuffle nodes that have been combined so far and permits combining of further shuffle nodes if all its users are in that list.

Differential Revision: https://reviews.llvm.org/D29399

llvm-svn: 294183
2017-02-06 13:44:45 +00:00
Matt Arsenault
c4ccc9b791 DAG: Constant fold fp16_to_fp/fp16_to_fp
This fixes emitting conversions of constants on targets
without legal f16 that need to use these for legalization.

llvm-svn: 293499
2017-01-30 16:57:41 +00:00
Craig Topper
76620cef51 [SelectionDAG] Make SDNode::getConstantOperandVal an inline method.
It's operation already exists manually in many places without using the method.

llvm-svn: 293421
2017-01-29 06:08:02 +00:00
Craig Topper
81db52beea [SelectionDAG] Teach getNode to simplify a couple easy cases of EXTRACT_SUBVECTOR
Summary:
This teaches getNode to simplify extracting from Undef. This is similar to what is done for EXTRACT_VECTOR_ELT. It also adds support for extracting from CONCAT_VECTOR when we can reuse one of the inputs to the concat. These seem like simple non-target specific optimizations.

For X86 we currently handle undef in extractSubvector, but not all EXTRACT_SUBVECTOR creations go through there.

Ultimately, my motivation here is to simplify extractSubvector and remove custom lowering for EXTRACT_SUBVECTOR since we don't do anything but handle undef and BUILD_VECTOR optimizations, but those should be DAG combines.

Reviewers: RKSimon, delena

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29000

llvm-svn: 292876
2017-01-24 02:36:59 +00:00
Simon Pilgrim
fb321451a1 [SelectionDAG] Improve knownbits handling of UMIN/UMAX (PR31293)
This patch improves the knownbits logic for unsigned integer min/max opcodes.

For UMIN we know that the result will have the maximum of the inputs' known leading zero bits in the result, similarly for UMAX the maximum of the inputs' leading one bits.

This is particularly useful for simplifying clamping patterns,. e.g. as SSE doesn't have a uitofp instruction we want to use sitofp instead where possible and for that we need to confirm that the top bit is not set.

Differential Revision: https://reviews.llvm.org/D28853

llvm-svn: 292528
2017-01-19 22:41:22 +00:00
Matt Arsenault
15def6a25a DAG: Consider nnan in isKnownNeverNaN
llvm-svn: 292328
2017-01-18 02:10:08 +00:00
Simon Pilgrim
7522ab562f [SelectionDAG] Add knownbits support for BITREVERSE
llvm-svn: 292130
2017-01-16 14:49:26 +00:00
Simon Pilgrim
a8edcf036b [SelectionDAG] Add support for BITREVERSE constant folding
We were relying on constant folding of the legalized instructions to do what constant folding we had previously

llvm-svn: 292114
2017-01-16 13:39:00 +00:00
Malcolm Parsons
26eb6a0783 Remove unused lambda captures. NFC
llvm-svn: 291916
2017-01-13 17:12:16 +00:00
Matt Arsenault
bc8f9b01ec Remove unused CONVERT_RNDSAT intrinsics
llvm-svn: 291607
2017-01-10 22:38:02 +00:00
Simon Dardis
4fc397dfdf [mips] Fix Mips MSA instrinsics
The usage of some MIPS MSA instrinsics that took immediates could crash LLVM
during lowering. This patch addresses that behaviour. Crucially this patch
also makes the use of intrinsics with out of range immediates as producing an
internal error.

The ld,st instrinsics would trigger an assertion failure for MIPS64 as their
lowering would attempt to add an i32 offset to a i64 pointer.

Reviewers: vkalintiris, slthakur

Differential Revision: https://reviews.llvm.org/D25438

llvm-svn: 291571
2017-01-10 16:40:57 +00:00
Simon Pilgrim
3d00c1e5ad [SelectionDAG] Early out from computeKnownBits when we know we will have no common bits.
Avoid extra (recursive) calls to computeKnownBits if we already know that there are no common known bits.

llvm-svn: 290490
2016-12-24 12:59:35 +00:00
Matt Arsenault
7363b816c7 DAG: Add helper for testing constant values
There are helpers for testing for constant or constant build_vector,
and for splat ConstantFP vectors, but not for a constantfp or
non-splat ConstantFP vector.

llvm-svn: 290317
2016-12-22 04:39:45 +00:00
Joel Jones
5b76390d23 Fix name typo in SelectonDAG
llvm-svn: 289969
2016-12-16 18:22:54 +00:00
Simon Pilgrim
f05854a8a9 [DAGCombiner] Try to use SelectionDAG::isKnownToBeAPowerOfTwo instead of just APInt::isPowerOf2
Generalize sdiv/udiv/srem/urem combines using APInt::isPowerOf2, which only works for const/splat-const values, to call SelectionDAG::isKnownToBeAPowerOfTwo instead which recognises many more cases.

Added a DAGCombiner::BuildLogBase2 helper since PowerOf2 combines often involve taking the log2 of such a value.

Differential Revision: https://reviews.llvm.org/D27714

llvm-svn: 289654
2016-12-14 15:08:13 +00:00
Stephan Bergmann
aba15d97df Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Simon Pilgrim
d5a20f83a2 [SelectionDAG] computeKnownBits - simplified knownbits sign extension. NFCI.
We don't need to extract+test the sign bit of the known ones/zeros, we can use sext which will handle all of this.

llvm-svn: 289534
2016-12-13 13:36:27 +00:00
Simon Pilgrim
cb8d466ab0 [SelectionDAG] Add support for EXTRACT_SUBVECTOR to ComputeNumSignBits
Pre-commit as discussed on D27657

llvm-svn: 289425
2016-12-12 10:29:43 +00:00
Simon Pilgrim
401af4781d [SelectionDAG] Add ability for computeKnownBits to peek through bitcasts from 'large element' scalar/vector to 'small element' vector.
Extension to D27129 which already supported bitcasts from 'small element' vector to 'large element' scalar/vector types.

llvm-svn: 289329
2016-12-10 17:00:00 +00:00
Simon Pilgrim
62680ef29e [SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes (REAPPLIED)
Reapplied with fix for PR31323 - X86 SSE2 vXi16 multiplies for illegal types were creating CONCAT_VECTORS nodes with vector inputs that might not total the number of elements in the result type.

llvm-svn: 289232
2016-12-09 17:53:11 +00:00
Simon Pilgrim
76dbac96c6 [SelectionDAG] Use SelectionDAG.getBuildVector helper. NFCI.
Makes interception of BUILD_VECTOR creation easier for debugging.

llvm-svn: 289218
2016-12-09 15:23:41 +00:00
Simon Pilgrim
3d9639ff3f [SelectionDAG] Add additional checks to CONCAT_VECTORS creation
Part of the work for PR31323 - add extra asserts checking that the input vectors are of consistent type and result in the correct number of vector elements.

llvm-svn: 289214
2016-12-09 14:27:52 +00:00
Simon Pilgrim
668cfba535 [SelectionDAG] Add partial BITCAST support to computeKnownBits
Adds support for bitcasting a little endian 'small element' vector to 'large element' scalar/vector (e.g. v16i8 to v4i32 or v2i32 to i64), which is required for PR30845. We extract the knownbits for each 'small element' part and concatenate the results together.

We can add support for big endian and 'large element' scalar/vector to 'small element' vector bitcasting once we have test cases for them.

Differential Revision: https://reviews.llvm.org/D27129

llvm-svn: 289200
2016-12-09 10:13:45 +00:00
Daniel Jasper
d4a88ded31 Revert "[SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes"
This reverts commit r288916 as it is currently causing a crasher in
Halide. Reproducer on llvm.org/PR31323. While it might be that halide is
generating invalid IR, llc shouldn't crash.

llvm-svn: 289194
2016-12-09 09:04:51 +00:00
Simon Pilgrim
e88a47ae36 [SelectionDAG] Add knownbits support for vector demandedelts in SMAX/SMIN/UMAX/UMIN opcodes
llvm-svn: 288926
2016-12-07 17:54:00 +00:00