aboutsummaryrefslogtreecommitdiff
path: root/test/Transforms/LoopVectorize
diff options
context:
space:
mode:
authorNadav Rotem <nrotem@apple.com>2013-01-07 21:54:51 +0000
committerNadav Rotem <nrotem@apple.com>2013-01-07 21:54:51 +0000
commit9a6c6a373629fb5a3cc5afd08aafa51339df95df (patch)
tree1cbd326c4bbe4297f2e8f43f828f7e6acad6ee45 /test/Transforms/LoopVectorize
parent6c1d4972cf1cd6b6072e31c05f97abb1ed7a8497 (diff)
LoopVectorizer: When we vectorizer and widen loops we process many elements at once. This is a good thing, except for
small loops. On small loops post-loop that handles scalars (and runs slower) can take more time to execute than the rest of the loop. This patch disables widening of loops with a small static trip count. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171798 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/Transforms/LoopVectorize')
-rw-r--r--test/Transforms/LoopVectorize/X86/unroll-small-loops.ll50
1 files changed, 50 insertions, 0 deletions
diff --git a/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll b/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll
new file mode 100644
index 0000000000..207598636c
--- /dev/null
+++ b/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll
@@ -0,0 +1,50 @@
+; RUN: opt < %s -loop-vectorize -mtriple=x86_64-apple-macosx10.8.0 -mcpu=corei7-avx2 -force-vector-width=4 -force-vector-unroll=0 -dce -S | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.8.0"
+;CHECK: @foo
+;CHECK: load <4 x i32>
+;CHECK-NOT: load <4 x i32>
+;CHECK: store <4 x i32>
+;CHECK-NOT: store <4 x i32>
+;CHECK: ret
+define i32 @foo(i32* nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32* %A, i64 %indvars.iv
+ %3 = load i32* %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, i32* %2, align 4
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+ %exitcond = icmp eq i32 %lftr.wideiv, 100
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+;CHECK: @bar
+;CHECK: store <4 x i32>
+;CHECK: store <4 x i32>
+;CHECK: ret
+define i32 @bar(i32* nocapture %A, i32 %n) nounwind uwtable ssp {
+ %1 = icmp sgt i32 %n, 0
+ br i1 %1, label %.lr.ph, label %._crit_edge
+
+.lr.ph: ; preds = %0, %.lr.ph
+ %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
+ %2 = getelementptr inbounds i32* %A, i64 %indvars.iv
+ %3 = load i32* %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, i32* %2, align 4
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+ %exitcond = icmp eq i32 %lftr.wideiv, %n
+ br i1 %exitcond, label %._crit_edge, label %.lr.ph
+
+._crit_edge: ; preds = %.lr.ph, %0
+ ret i32 undef
+}