Commit Graph

7 Commits

Author SHA1 Message Date
Benjamin Kramer
0ef0e2e6d0 LoopVectorize: Emit reductions as log2(vectorsize) shuffles + vector ops instead of scalar operations.
For example on x86 with SSE4.2 a <8 x i8> add reduction becomes
	movdqa	%xmm0, %xmm1
	movhlps	%xmm1, %xmm1            ## xmm1 = xmm1[1,1]
	paddw	%xmm0, %xmm1
	pshufd	$1, %xmm1, %xmm0        ## xmm0 = xmm1[1,0,0,0]
	paddw	%xmm1, %xmm0
	phaddw	%xmm0, %xmm0
	pextrb	$0, %xmm0, %edx

instead of
	pextrb	$2, %xmm0, %esi
	pextrb	$0, %xmm0, %edx
	addb	%sil, %dl
	pextrb	$4, %xmm0, %esi
	addb	%dl, %sil
	pextrb	$6, %xmm0, %edx
	addb	%sil, %dl
	pextrb	$8, %xmm0, %esi
	addb	%dl, %sil
	pextrb	$10, %xmm0, %edi
	pextrb	$14, %xmm0, %edx
	addb	%sil, %dil
	pextrb	$12, %xmm0, %esi
	addb	%dil, %sil
	addb	%sil, %dl

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170439 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-18 18:40:20 +00:00
Nadav Rotem
e57b2cbce6 LoopVectorize: Preserve NSW, NUW and IsExact flags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167174 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-31 21:40:39 +00:00
Nadav Rotem
cc03331caa LoopVectorize: Fix a bug in the initialization of reduction variables. AND needs to start at all-one
while XOR, and OR need to start at zero.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167032 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-30 18:12:36 +00:00
Nadav Rotem
8dbac7b529 Add support for additional reduction variables: AND, OR, XOR.
Patch by Paul Redmond <paul.redmond@intel.com>.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166649 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-25 00:08:41 +00:00
Nadav Rotem
50bec6f8c4 LoopVectorizer: Add a basic cost model which uses the VTTI interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166620 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-24 20:36:32 +00:00
Nadav Rotem
c847872629 Add support for reduction variables that do not start at zero.
This is important for nested-loop reductions such as :

In the innermost loop, the induction variable does not start with zero:

for (i = 0 .. n)
 for (j = 0 .. m)
  sum += ...



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166387 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-21 05:52:51 +00:00
Nadav Rotem
5dbe64e2bc Vectorizer: Add support for loop reductions.
For example:

  for (i=0; i<n; i++)
   sum += A[i] +  B[i] + i;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166351 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-19 23:05:40 +00:00