1273 Commits

Author SHA1 Message Date
Sanjay Patel
05d5e213c4 merge consecutive stores of extracted vector elements (PR21711)
This is a 2nd try at the same optimization as http://reviews.llvm.org/D6698. 
That patch was checked in at r224611, but reverted at r225031 because it
caused a failure outside of the regression tests.

The cause of the crash was not recognizing consecutive stores that have mixed
source values (loads and vector element extracts), so this patch adds a check
to bail out if any store value is not coming from a vector element extract.

This patch also refactors the shared logic of the constant source and vector
extracted elements source cases into a helper function.

Differential Revision: http://reviews.llvm.org/D6850
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226845 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 18:21:26 +00:00
Michael Kuperstein
a52ddfa930 [DAGCombine] Produce better code for constant splats
This solves PR22276.
Splats of constants would sometimes produce redundant shuffles, sometimes ridiculously so (see the PR for details). Fold these shuffles into BUILD_VECTORs early on instead.

Differential Revision: http://reviews.llvm.org/D7093

Fixed recommit of r226811.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226816 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 13:07:28 +00:00
Michael Kuperstein
8fc1c3a619 Revert r226811, MSVC accepts code sane compilers don't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226814 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 12:48:07 +00:00
Michael Kuperstein
0a979a09ae [DAGCombine] Produce better code for constant splats
This solves PR22276.
Splats of constants would sometimes produce redundant shuffles, sometimes ridiculously so (see the PR for details). Fold these shuffles into BUILD_VECTORs early on instead.

Differential Revision: http://reviews.llvm.org/D7093

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226811 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 12:37:23 +00:00
Elena Demikhovsky
2785766bc8 Fixed a bug in type legalizer for masked load/store intrinsics.
The problem occurs when after vectorization we have type
<2 x i32>. This type is promoted to <2 x i64> and then requires
additional efforts for expanding loads and truncating stores.
I added EXPAND / TRUNCATE attributes to the masked load/store
SDNodes. The code now contains additional shuffles.
I've prepared changes in the cost estimation for masked memory
operations, it will be submitted separately.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226808 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 12:07:59 +00:00
Elena Demikhovsky
9cb8df2c75 Fixed a comment
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226806 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 10:01:36 +00:00
Elena Demikhovsky
cdce03426d Fixed a bug in narrowing store operation.
Type MVT::i1 became legal in KNL, but store operation can't be narrowed to this type,
since the size of VT (1 bit) is not equal to its actual store size(8 bits).

Added a test provided by David (dag@cray.com)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226805 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-22 09:39:08 +00:00
Tim Northover
f5f8a3e6a6 DAGCombine: fold (or (and X, M), (and X, N)) -> (and X, (or M, N))
It can help with argument juggling on some targets, and is generally a good
idea.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226740 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 23:17:19 +00:00
Tim Northover
c49e57ade1 Revert "DAGCombine: fold (or (and X, M), (and X, N)) -> (and X, (or M, N))"
It hadn't gone through review yet, but was still on my local copy.

This reverts commit r226663

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226665 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 15:48:52 +00:00
Tim Northover
47f47f5d2a DAGCombine: fold (or (and X, M), (and X, N)) -> (and X, (or M, N))
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226663 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-21 15:43:28 +00:00
Mehdi Amini
5eed637b34 Improve DAG combine pass on certain IR vector patterns
Loading 2 2x32-bit float vectors into the bottom half of a 256-bit vector
produced suboptimal code in AVX2 mode with certain IR combinations.

In particular, the IR optimizer folded 2f32 + 2f32 -> 4f32, 4f32 + 4f32
(undef) -> 8f32 into a 2f32 + 2f32 -> 8f32, which seems more canonical,
but then mysteriously generated rather bad code; the movq/movhpd combination
didn't match.

The problem lay in the BUILD_VECTOR optimization path. The 2f32 inputs
would get promoted to 4f32 by the type legalizer, eventually resulting
in a BUILD_VECTOR on two 4f32 into an 8f32. The BUILD_VECTOR then, recognizing
these were both half the output size, concatted them and then produced
a shuffle. However, the resulting concat + shuffle was more complex than
it should be; in the case where the upper half of the output is undef, we
probably want to generate shuffle + concat instead.

This enhancement causes the vector_shuffle combine step to recognize this
suboptimal pattern and correct it. I included it there instead of in BUILD_VECTOR
in case the same suboptimal pattern occurs for other reasons.

This results in the optimizer correctly producing the optimal movq + movhpd
sequence for all three variations on this IR, even with AVX2.

I've included a test case.

Radar link: rdar://problem/19287012
Fix for PR 21943.

From: Fiona Glaser <fglaser@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226360 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-17 01:35:56 +00:00
Chandler Carruth
1b279144ec [cleanup] Re-sort all the #include lines in LLVM using
utils/sort_includes.py.

I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225974 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 11:23:27 +00:00
Mehdi Amini
cfe92407cd DAG Combiner: Fold SelectCC When Cond is UNDEF
In case folding a node end up with a NaN as operand for the select, 
the folding of the condition of the selectcc node returns "UNDEF".

Differential Revision: http://reviews.llvm.org/D6889



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225952 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 05:45:24 +00:00
Matthias Braun
12232769b3 DAGCombiner: simplify by using condition variables; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225836 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 22:17:46 +00:00
Matt Arsenault
7c06364dc0 R600: Implement getRecipEstimate
This requires a new hook to prevent expanding sqrt in terms
of rsqrt and reciprocal. v_rcp_f32, v_rsq_f32, and v_sqrt_f32 are
all the same rate, so this expansion would just double the number
of instructions and cycles.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225828 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 20:53:23 +00:00
Olivier Sallenave
9dd21f4380 Added TLI hook for isFPExtFree. Some of the FMA combine heuristics are now guarded with that hook.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225795 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 15:06:36 +00:00
Matt Arsenault
29ad7506e1 Combine fcmp + select to fminnum / fmaxnum if no nans and legal
Also require unsafe FP math for no since there isn't a way to
test for signed zeros.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225744 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-13 00:43:00 +00:00
Hal Finkel
8e1d151abe [DAGCombine] Remainder of fix to r225380 (More FMA folding opportunities)
As pointed out by Aditya (and Owen), when we elide an FP extend to form an FMA,
we need to extend the incoming operands so that the resulting node will really
be legal. This is currently enabled only for PowerPC, and it happens to work
there regardless, but this should fix the functionality for everyone else
should anyone else wish to use it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225492 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-09 01:29:29 +00:00
Hal Finkel
40ddb2ce8f Partial fix to r225380 (More FMA folding opportunities)
As pointed out by Aditya (and Owen), there are two things wrong with this code.
First, it adds patterns which elide FP extends when forming FMAs, and that might
not be profitable on all targets (it belongs behind the pre-existing
aggressive-FMA-formation flag). This is fixed by this change.

Second, the resulting nodes might have operands of different types (the
extensions need to be re-added). That will be fixed in the follow-up commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225485 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-09 00:45:54 +00:00
Ahmed Bougacha
7fac1d945f [SelectionDAG] Allow targets to specify legality of extloads' result
type (in addition to the memory type).

The *LoadExt* legalization handling used to only have one type, the
memory type.  This forced users to assume that as long as the extload
for the memory type was declared legal, and the result type was legal,
the whole extload was legal.

However, this isn't always the case.  For instance, on X86, with AVX,
this is legal:
    v4i32 load, zext from v4i8
but this isn't:
    v4i64 load, zext from v4i8
Whereas v4i64 is (arguably) legal, even without AVX2.

Note that the same thing was done a while ago for truncstores (r46140),
but I assume no one needed it yet for extloads, so here we go.

Calls to getLoadExtAction were changed to add the value type, found
manually in the surrounding code.

Calls to setLoadExtAction were mechanically changed, by wrapping the
call in a loop, to match previous behavior.  The loop iterates over
the MVT subrange corresponding to the memory type (FP vectors, etc...).
I also pulled neighboring setTruncStoreActions into some of the loops;
those shouldn't make a difference, as the additional types are illegal.
(e.g., i128->i1 truncstores on PPC.)

No functional change intended.

Differential Revision: http://reviews.llvm.org/D6532


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225421 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-08 00:51:32 +00:00
Olivier Sallenave
033a537a84 More FMA folding opportunities.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225380 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-07 20:54:17 +00:00
Olivier Sallenave
bc2572cac5 Test commit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225368 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-07 19:45:17 +00:00
Craig Topper
9bf73516cb Replace several 'assert(false' with 'llvm_unreachable' or fold a condition into the assert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225160 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-05 10:15:49 +00:00
Alexey Samsonov
c0319dd9c2 Revert "merge consecutive stores of extracted vector elements"
This reverts commit r224611. This change causes crashes
in X86 DAG->DAG Instruction Selection.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225031 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-31 00:40:28 +00:00
Mehdi Amini
8548c2453f Always assert in DAGCombine and not only when -debug is enabled
Right now in DAG Combine check the validity of the returned type 
only when -debug is given on the command line. However usually 
the test cases in the validation does not use -debug. 
An Assert build should always check this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224779 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-23 18:59:02 +00:00
Michael Kuperstein
1f0ddef593 [DagCombine] Improve DAGCombiner BUILD_VECTOR when it has two sources of elements
This partially fixes PR21943.

For AVX, we go from:

vmovq   (%rsi), %xmm0
vmovq   (%rdi), %xmm1
vpermilps       $-27, %xmm1, %xmm2 ## xmm2 = xmm1[1,1,2,3]
vinsertps       $16, %xmm2, %xmm1, %xmm1 ## xmm1 = xmm1[0],xmm2[0],xmm1[2,3]
vinsertps       $32, %xmm0, %xmm1, %xmm1 ## xmm1 = xmm1[0,1],xmm0[0],xmm1[3]
vpermilps       $-27, %xmm0, %xmm0 ## xmm0 = xmm0[1,1,2,3]
vinsertps       $48, %xmm0, %xmm1, %xmm0 ## xmm0 = xmm1[0,1,2],xmm0[0]

To the expected:

vmovq   (%rdi), %xmm0
vmovhpd (%rsi), %xmm0, %xmm0
retq

Fixing this for AVX2 is still open.

Differential Revision: http://reviews.llvm.org/D6749

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224759 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-23 08:59:45 +00:00
Sanjay Patel
3c3cd10928 merge consecutive stores of extracted vector elements
Add a path to DAGCombiner::MergeConsecutiveStores() 
to combine multiple scalar stores when the store operands
are extracted vector elements. This is a partial fix for
PR21711 ( http://llvm.org/bugs/show_bug.cgi?id=21711 ).

For the new test case, codegen improves from:

   vmovss  %xmm0, (%rdi)
   vextractps      $1, %xmm0, 4(%rdi)
   vextractps      $2, %xmm0, 8(%rdi)
   vextractps      $3, %xmm0, 12(%rdi)
   vextractf128    $1, %ymm0, %xmm0
   vmovss  %xmm0, 16(%rdi)
   vextractps      $1, %xmm0, 20(%rdi)
   vextractps      $2, %xmm0, 24(%rdi)
   vextractps      $3, %xmm0, 28(%rdi)
   vzeroupper
   retq

To:

   vmovups	%ymm0, (%rdi)
   vzeroupper
   retq

Patch reviewed by Nadav Rotem.

Differential Revision: http://reviews.llvm.org/D6698



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224611 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 20:23:41 +00:00
Michael Kuperstein
fd350586f5 [DAGCombine] Slightly improve lowering of BUILD_VECTOR into a shuffle.
This handles the case of a BUILD_VECTOR being constructed out of elements extracted from a vector twice the size of the result vector. Previously this was always scalarized. Now, we try to construct a shuffle node that feeds on extract_subvectors.

This fixes PR15872 and provides a partial fix for PR21711.

Differential Revision: http://reviews.llvm.org/D6678

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224429 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-17 12:32:17 +00:00
Matt Arsenault
6e6318f148 Add target hook for whether it is profitable to reduce load widths
Add an option to disable optimization to shrink truncated larger type
loads to smaller type loads. On SI this prevents using scalar load
instructions in some cases, since there are no scalar extloads.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224084 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-12 00:00:24 +00:00
Owen Anderson
59bf8e81f3 Fix a few instances found in SelectionDAG where we were not handling F16 at parity with F32 and F64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223760 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-09 06:50:39 +00:00
Simon Pilgrim
94590ca4cf [InstCombine] Minor optimization for bswap with binary ops
Added instcombine optimizations for BSWAP with AND/OR/XOR ops:

OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) )
OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) )

Since its just a one liner, I've also added BSWAP to the DAGCombiner equivalent as well:

fold (OP (bswap x), (bswap y)) -> (bswap (OP x, y))

Refactored bswap-fold tests to use FileCheck instead of just checking that the bswaps had gone.

Differential Revision: http://reviews.llvm.org/D6407



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223349 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-04 09:44:01 +00:00
Elena Demikhovsky
73ae1df82c Masked Load / Store Intrinsics - the CodeGen part.
I'm recommiting the codegen part of the patch.
The vectorizer part will be send to review again.

Masked Vector Load and Store Intrinsics.
Introduced new target-independent intrinsics in order to support masked vector loads and stores. The loop vectorizer optimizes loops containing conditional memory accesses by generating these intrinsics for existing targets AVX2 and AVX-512. The vectorizer asks the target about availability of masked vector loads and stores.
Added SDNodes for masked operations and lowering patterns for X86 code generator.
Examples:
<16 x i32> @llvm.masked.load.v16i32(i8* %addr, <16 x i32> %passthru, i32 4 /* align */, <16 x i1> %mask)
declare void @llvm.masked.store.v8f64(i8* %addr, <8 x double> %value, i32 4, <8 x i1> %mask)

Scalarizer for other targets (not AVX2/AVX-512) will be done in a separate patch.

http://reviews.llvm.org/D6191



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223348 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-04 09:40:44 +00:00
Duncan P. N. Exon Smith
54786a0936 Revert "Masked Vector Load and Store Intrinsics."
This reverts commit r222632 (and follow-up r222636), which caused a host
of LNT failures on an internal bot.  I'll respond to the commit on the
list with a reproduction of one of the failures.

Conflicts:
	lib/Target/X86/X86TargetTransformInfo.cpp

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222936 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-28 21:29:14 +00:00
Elena Demikhovsky
ae1ae2c3a1 Masked Vector Load and Store Intrinsics.
Introduced new target-independent intrinsics in order to support masked vector loads and stores. The loop vectorizer optimizes loops containing conditional memory accesses by generating these intrinsics for existing targets AVX2 and AVX-512. The vectorizer asks the target about availability of masked vector loads and stores.
Added SDNodes for masked operations and lowering patterns for X86 code generator.
Examples:
<16 x i32> @llvm.masked.load.v16i32(i8* %addr, <16 x i32> %passthru, i32 4 /* align */, <16 x i1> %mask)
declare void @llvm.masked.store.v8f64(i8* %addr, <8 x double> %value, i32 4, <8 x i1> %mask)

Scalarizer for other targets (not AVX2/AVX-512) will be done in a separate patch.

http://reviews.llvm.org/D6191



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222632 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-23 08:07:43 +00:00
Andrea Di Biagio
607099b697 [DAG] Teach how to turn a build_vector into a shuffle if some of the operands are zero.
Before this patch, the DAGCombiner only tried to convert build_vector dag nodes
into shuffles if all operands were either extract_vector_elt or undef.

This patch improves that logic and teaches the DAGCombiner how to deal with
build_vector dag nodes where one or more operands are zero. A build_vector
dag node with some zero operands is turned into a shuffle only if the resulting
shuffle mask is legal for the target.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222536 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-21 14:32:06 +00:00
Andrea Di Biagio
04fab61b35 [DAG] Refactor the shuffle combining logic in DAGCombiner. NFC.
This patch simplifies the logic that combines a pair of shuffle nodes into
a single shuffle if there is a legal mask. Also added comments to better
describe the algorithm. No functional change intended.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222522 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-21 11:33:07 +00:00
Hao Liu
09ad94decb DAGCombiner: Allow the DAGCombiner to combine multiple FDIVs with the same divisor info FMULs by the reciprocal.
E.g., ( a / D; b / D ) -> ( recip = 1.0 / D; a * recip; b * recip)

A hook is added to allow the target to control whether it needs to do such combine.

Reviewed in http://reviews.llvm.org/D6334


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222510 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-21 06:39:58 +00:00
David Blaikie
5401ba7099 Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222334 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-19 07:49:26 +00:00
Oliver Stannard
d9d2703b71 Fix optimisations of SELECT_CC which assumed result is boolean
Some optimisations in DAGCombiner cause miscompilations for targets that use
TargetLowering::UndefinedBooleanContent, because they assume that the results
of a SELECT_CC node are boolean values, and can be safely ANDed, ORed and
XORed. These optimisations are only valid for targets that use
ZeroOrOneBooleanContent or ZeroOrNegativeOneBooleanContent.

This is a follow-up to D6210/r221693.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222123 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-17 10:49:31 +00:00
Andrea Di Biagio
37f645cb34 [DAG] Improved target independent vector shuffle folding logic.
This patch teaches the DAGCombiner how to combine shuffles according to rules:
   shuffle(shuffle(A, Undef, M0), B, M1) -> shuffle(B, A, M2)
   shuffle(shuffle(A, B, M0), B, M1) -> shuffle(B, A, M2)
   shuffle(shuffle(A, B, M0), A, M1) -> shuffle(B, A, M2)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222090 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-15 22:56:25 +00:00
Oliver Stannard
659b1491b8 LLVM incorrectly folds xor into select
LLVM replaces the SelectionDAG pattern (xor (set_cc cc x y) 1) with
(set_cc !cc x y), which is only correct when the xor has type i1.
Instead, we should check that the constant operand to the xor is all
ones.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221693 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 17:36:01 +00:00
Andrea Di Biagio
042bee88f3 [X86] Teach method 'isVectorClearMaskLegal' how to check for legal blend masks.
This patch improves the folding of vector AND nodes into blend operations for
targets that feature SSE4.1. A vector AND node where one of the operands is
a constant build_vector with elements that are either zero or all-ones can be
converted into a blend.

This allows for example to simplify the following code:

define <4 x i32> @test(<4 x i32> %A, <4 x i32> %B) {
  %1 = and <4 x i32> %A, <i32 0, i32 0, i32 0, i32 -1>
  %2 = and <4 x i32> %B, <i32 -1, i32 -1, i32 -1, i32 0>
  %3 = or <4 x i32> %1, %2
  ret <4 x i32> %3
}

Before this patch llc (-mcpu=corei7) generated:
        andps  LCPI1_0(%rip), %xmm0, %xmm0
        andps  LCPI1_1(%rip), %xmm1, %xmm1
        orps   %xmm1, %xmm0, %xmm0
        retq

With this patch we generate a single 'vpblendw'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221343 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-05 13:04:14 +00:00
Paul Robinson
c3e82bf9f5 Normally an 'optnone' function goes through fast-isel, which does not
call DAGCombiner. But we ran into a case (on Windows) where the
calling convention causes argument lowering to bail out of fast-isel,
and we end up in CodeGenAndEmitDAG() which does run DAGCombiner.
So, we need to make DAGCombiner check for 'optnone' after all.

Commit includes the test that found this, plus another one that got
missed in the original optnone work.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221168 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-03 18:19:26 +00:00
Louis Gerbarg
4c77b29082 Fix incorrect invariant check in DAG Combine
Earlier this summer I fixed an issue where we were incorrectly combining
multiple loads that had different constraints such alignment, invariance,
temporality, etc. Apparently in one case I made copt paste error and swapped
alignment and invariance.

Tests included.

rdar://18816719

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220933 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-30 22:21:03 +00:00
NAKAMURA Takumi
7710e2553b Whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220857 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-29 15:23:11 +00:00
Sanjay Patel
a46f06efe2 Use rsqrt (X86) to speed up reciprocal square root calcs
This is a first step for generating SSE rsqrt instructions for
reciprocal square root calcs when fast-math is allowed.

For now, be conservative and only enable this for AMD btver2
where performance improves significantly - for example, 29%
on llvm/projects/test-suite/SingleSource/Benchmarks/BenchmarkGame/n-body.c
(if we convert the data type to single-precision float).

This patch adds a two constant version of the Newton-Raphson
refinement algorithm to DAGCombiner that can be selected by any target
via a parameter returned by getRsqrtEstimate()..

See PR20900 for more details:
http://llvm.org/bugs/show_bug.cgi?id=20900

Differential Revision: http://reviews.llvm.org/D5658



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220570 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-24 17:02:16 +00:00
Benjamin Kramer
9552fcab70 Strength reduce constant-sized vectors into arrays. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220412 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-22 19:55:26 +00:00
Matt Arsenault
015776f38c Add minnum / maxnum codegen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220342 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-21 23:01:01 +00:00
Jan Vesely
cef793e8c7 SelectionDAG: Add sext_inreg optimizations
v2: use dyn_cast
    fixup comments
v3: use cast

Reviewed-by: Matt Arsenault <arsenm2@gmail.com>
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220044 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-17 14:45:25 +00:00
Sanjay Patel
a4554c2897 Improve sqrt estimate algorithm (fast-math)
This patch changes the fast-math implementation for calculating sqrt(x) from:
y = 1 / (1 / sqrt(x))
to:
y = x * (1 / sqrt(x))

This has 2 benefits: less code / faster code and one less estimate instruction 
that may lose precision.

The only target that will be affected (until http://reviews.llvm.org/D5658 is approved)
is PPC. The difference in codegen for PPC is 2 less flops for a single-precision sqrtf
or vector sqrtf and 4 less flops for a double-precision sqrt. 
We also eliminate a constant load and extra register usage.

Differential Revision: http://reviews.llvm.org/D5682



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219445 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-09 21:26:35 +00:00