RPCSX/llvm
1
0
Fork 0
mirror of https://github.com/RPCSX/llvm.git synced 2024-12-11 21:57:55 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

[SLP vectorizer]: Choose the best consecutive candidate to pair with a store instruction.

Browse Source 
The patch changes the SLPVectorizer::vectorizeStores to choose the immediate
succeeding or preceding candidate for a store instruction when it has multiple
consecutive candidates. In this way it has better chance to find more slp
vectorization opportunities.

Differential Revision: http://reviews.llvm.org/D10445


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243666 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Wei Mi 2015-07-30 17:40:39 +00:00
parent 778e06475b
commit 4db6728b3a
2 changed files with 56 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
lib/Transforms/Vectorize/SLPVectorizer.cpp
View File

@ -3262,15 +3262,26 @@ bool SLPVectorizer::vectorizeStores(ArrayRef<StoreInst *> Stores,
// Do a quadratic search on all of the given stores and find
// all of the pairs of stores that follow each other.
SmallVector<unsigned, 16> IndexQueue;
for (unsigned i = 0, e = Stores.size(); i < e; ++i) {
for (unsigned j = 0; j < e; ++j) {
if (i == j)
continue;
const DataLayout &DL = Stores[i]->getModule()->getDataLayout();
if (R.isConsecutiveAccess(Stores[i], Stores[j], DL)) {
Tails.insert(Stores[j]);
const DataLayout &DL = Stores[i]->getModule()->getDataLayout();
IndexQueue.clear();
// If a store has multiple consecutive store candidates, search Stores
// array according to the sequence: from i+1 to e, then from i-1 to 0.
// This is because usually pairing with immediate succeeding or preceding
// candidate create the best chance to find slp vectorization opportunity.
unsigned j = 0;
for (j = i + 1; j < e; ++j)
IndexQueue.push_back(j);
for (j = i; j > 0; --j)
IndexQueue.push_back(j - 1);
for (auto &k : IndexQueue) {
if (R.isConsecutiveAccess(Stores[i], Stores[k], DL)) {
Tails.insert(Stores[k]);
Heads.insert(Stores[i]);
ConsecutiveChain[Stores[i]] = Stores[j];
ConsecutiveChain[Stores[i]] = Stores[k];
break;
}
}
}

38
test/Transforms/SLPVectorizer/X86/pr23510.ll Normal file
View File

@ -0,0 +1,38 @@
; PR23510
; RUN: opt < %s -basicaa -slp-vectorizer -S | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; CHECK-LABEL: @_Z3fooPml(
; CHECK: lshr <2 x i64>
; CHECK: lshr <2 x i64>
@total = global i64 0, align 8
define void @_Z3fooPml(i64* nocapture %a, i64 %i) {
entry:
%tmp = load i64, i64* %a, align 8
%shr = lshr i64 %tmp, 4
store i64 %shr, i64* %a, align 8
%arrayidx1 = getelementptr inbounds i64, i64* %a, i64 1
%tmp1 = load i64, i64* %arrayidx1, align 8
%shr2 = lshr i64 %tmp1, 4
store i64 %shr2, i64* %arrayidx1, align 8
%arrayidx3 = getelementptr inbounds i64, i64* %a, i64 %i
%tmp2 = load i64, i64* %arrayidx3, align 8
%tmp3 = load i64, i64* @total, align 8
%add = add i64 %tmp3, %tmp2
store i64 %add, i64* @total, align 8
%tmp4 = load i64, i64* %a, align 8
%shr5 = lshr i64 %tmp4, 4
store i64 %shr5, i64* %a, align 8
%tmp5 = load i64, i64* %arrayidx1, align 8
%shr7 = lshr i64 %tmp5, 4
store i64 %shr7, i64* %arrayidx1, align 8
%tmp6 = load i64, i64* %arrayidx3, align 8
%tmp7 = load i64, i64* @total, align 8
%add9 = add i64 %tmp7, %tmp6
store i64 %add9, i64* @total, align 8
ret void
}