17 Commits

Author SHA1 Message Date
Quentin Colombet
24508d33fb Revert r227242 - Merge vector stores into wider vector stores (PR21711).
This commit creates infinite loop in DAG combine for in the LLVM test-suite
for aarch64 with mcpu=cylcone (just having neon may be enough to expose this).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227272 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 23:58:01 +00:00
Sanjay Patel
c94f9d3d2f Merge vector stores into wider vector stores (PR21711)
This patch resolves part of PR21711 ( http://llvm.org/bugs/show_bug.cgi?id=21711 ).

The 'f3' test case in that report presents a situation where we have two 128-bit
stores extracted from a 256-bit source vector. 

Instead of producing this:

vmovaps %xmm0, (%rdi)
vextractf128    $1, %ymm0, 16(%rdi)

This patch merges the 128-bit stores into a single 256-bit store:

vmovups %ymm0, (%rdi)

Differential Revision: http://reviews.llvm.org/D7208



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227242 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-27 20:50:27 +00:00
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
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
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
Sanjay Patel
9ab434750a fix typo, add spaces; NFC
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224384 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-16 22:48:42 +00:00
Hal Finkel
24517d023f Add the ability to use GEPs for address sinking in CGP
The current memory-instruction optimization logic in CGP, which sinks parts of
the address computation that can be adsorbed by the addressing mode, does this
by explicitly converting the relevant part of the address computation into
IR-level integer operations (making use of ptrtoint and inttoptr). For most
targets this is currently not a problem, but for targets wishing to make use of
IR-level aliasing analysis during CodeGen, the use of ptrtoint/inttoptr is a
problem for two reasons:
  1. BasicAA becomes less powerful in the face of the ptrtoint/inttoptr
  2. In cases where type-punning was used, and BasicAA was used
     to override TBAA, BasicAA may no longer do so. (this had forced us to disable
     all use of TBAA in CodeGen; something which we can now enable again)

This (use of GEPs instead of ptrtoint/inttoptr) is not currently enabled by
default (except for those targets that use AA during CodeGen), and so aside
from some PowerPC subtargets and SystemZ, there should be no change in
behavior. We may be able to switch completely away from the ptrtoint/inttoptr
sinking on all targets, but further testing is required.

I've doubled-up on a number of existing tests that are sensitive to the
address sinking behavior (including some store-merging tests that are
sensitive to the order of the resulting ADD operations at the SDAG level).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206092 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-12 00:59:48 +00:00
Stephen Lin
cf2ab764db Update to more CodeGen tests to use CHECK-LABEL for labels corresponding to function definitions for more informative error messages. No functionality change.
All changes were made by the following bash script:

  find test/CodeGen -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    grep -q "^; *RUN: *llc.*debug" $NAME && continue
    grep -q "^; *RUN:.*llvm-objdump" $NAME && continue
    grep -q "^; *RUN: *opt.*" $NAME && continue
    TEMP=`mktemp -t temp`
    cp $NAME $TEMP
    sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
    while read FUNC; do
      sed -i '' "s/;\([A-Za-z0-9_-]*\)\([A-Za-z0-9_-]*\):\( *\)$FUNC[:]* *\$/;\1\2-LABEL:\3$FUNC:/g" $TEMP
    done
    sed -i '' "s/;\(.*\)-LABEL-LABEL:/;\1-LABEL:/" $TEMP
    sed -i '' "s/;\(.*\)-NEXT-LABEL:/;\1-NEXT:/" $TEMP
    sed -i '' "s/;\(.*\)-NOT-LABEL:/;\1-NOT:/" $TEMP
    sed -i '' "s/;\(.*\)-DAG-LABEL:/;\1-DAG:/" $TEMP
    mv $TEMP $NAME
  done

This script catches a superset of the cases caught by the script associated with commit r186280. It initially found some false positives due to unusual constructs in a minority of tests; all such cases were disambiguated first in commit r186621.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186624 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-18 22:47:09 +00:00
Arnold Schwaighofer
f28a29b776 Merge load/store sequences with adresses: base + index + offset
We would also like to merge sequences that involve a variable index like in the
example below.

    int index = *idx++
    int i0 = c[index+0];
    int i1 = c[index+1];
    b[0] = i0;
    b[1] = i1;

By extending the parsing of the base pointer to handle dags that contain a
base, index, and offset we can handle examples like the one above.

The dag for the code above will look something like:

 (load (i64 add (i64 copyfromreg %c)
                (i64 signextend (i8 load %index))))

 (load (i64 add (i64 copyfromreg %c)
                (i64 signextend (i32 add (i32 signextend (i8 load %index))
                                         (i32 1)))))

The code that parses the tree ignores the intermediate sign extensions. However,
if there is a sign extension it needs to be on all indexes.

 (load (i64 add (i64 copyfromreg %c)
                (i64 signextend (add (i8 load %index)
                                     (i8 1))))
 vs

 (load (i64 add (i64 copyfromreg %c)
                (i64 signextend (i32 add (i32 signextend (i8 load %index))
                                         (i32 1)))))
radar://13536387

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178483 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 18:12:58 +00:00
Nadav Rotem
6cc4b8d1eb Dont merge consecutive loads/stores into vectors when noimplicitfloat is used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175190 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-14 18:28:52 +00:00
Nadav Rotem
ba95865441 On Sandybridge split unaligned 256bit stores into two xmm-sized stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172894 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-19 08:38:41 +00:00
Nadav Rotem
ea2c50c041 When merging connsecutive stores, use vectors to store the constant zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165267 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-04 22:35:15 +00:00
Nadav Rotem
c653de6c0f A DAGCombine optimization for mergeing consecutive stores to memory. The optimization
is not profitable in many cases because modern processors perform multiple stores
in parallel and merging stores prior to merging requires extra work. We handle two main cases:

1. Store of multiple consecutive constants:
  q->a = 3;
  q->4 = 5;
In this case we store a single legal wide integer.

2. Store of multiple consecutive loads:
  int a = p->a;
  int b = p->b;
  q->a = a;
  q->b = b;
In this case we load/store either ilegal vector registers or legal wide integer registers.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165125 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-03 16:11:15 +00:00
Nadav Rotem
73fab91f2c Revert r164910 because it causes failures to several phase2 builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164911 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-30 07:17:56 +00:00
Nadav Rotem
e5f163a3b9 A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
 int a = p->a;
 int b = p->b;
 q->a = a;
 q->b = b;

2. Consecutive stores where the values are constants. Foe example:
 q->a = 4;
 q->b = 5;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164910 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-30 06:24:14 +00:00
Duncan Sands
454627252b Speculatively revert commit 164885 (nadav) in the hope of ressurecting a pile of
buildbots.  Original commit message:

A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
  int a = p->a;
  int b = p->b;
  q->a = a;
  q->b = b;

2. Consecutive stores where the values are constants. Foe example:
  q->a = 4;
  q->b = 5;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164890 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-29 10:25:35 +00:00
Nadav Rotem
72f7b0811e A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
  int a = p->a;
  int b = p->b;
  q->a = a;
  q->b = b;

2. Consecutive stores where the values are constants. Foe example:
  q->a = 4;
  q->b = 5;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164885 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-29 06:33:25 +00:00