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| author | Nadav Rotem <nrotem@apple.com> | 2013-01-07 21:54:51 +0000 |
|---|---|---|
| committer | Nadav Rotem <nrotem@apple.com> | 2013-01-07 21:54:51 +0000 |
| commit | 9a6c6a373629fb5a3cc5afd08aafa51339df95df (patch) | |
| tree | 1cbd326c4bbe4297f2e8f43f828f7e6acad6ee45 /test/Transforms | |
| parent | 6c1d4972cf1cd6b6072e31c05f97abb1ed7a8497 (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')
| -rw-r--r-- | test/Transforms/LoopVectorize/X86/unroll-small-loops.ll | 50 |
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 +} |