|  | ; RUN: opt -basicaa -loop-idiom < %s -S | FileCheck %s | 
|  | target datalayout = "e-p:64:64:64:32-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" | 
|  |  | 
|  | ; CHECK: @.memset_pattern = private unnamed_addr constant [4 x i32] [i32 2, i32 2, i32 2, i32 2], align 16 | 
|  |  | 
|  | target triple = "x86_64-apple-darwin10.0.0" | 
|  |  | 
|  | ;void test(int *f, unsigned n) { | 
|  | ;  for (unsigned i = 0; i < 2 * n; i += 2) { | 
|  | ;    f[i] = 0; | 
|  | ;    f[i+1] = 0; | 
|  | ;  } | 
|  | ;} | 
|  | define void @test(i32* %f, i32 %n) nounwind ssp { | 
|  | entry: | 
|  | %0 = shl i32 %n, 1 | 
|  | %cmp1 = icmp eq i32 %0, 0 | 
|  | br i1 %cmp1, label %for.end, label %for.body.preheader | 
|  |  | 
|  | for.body.preheader:                               ; preds = %entry | 
|  | br label %for.body | 
|  |  | 
|  | for.body:                                         ; preds = %for.body.preheader, %for.body | 
|  | %indvars.iv = phi i32 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.body ] | 
|  | %arrayidx = getelementptr inbounds i32, i32* %f, i32 %indvars.iv | 
|  | store i32 0, i32* %arrayidx, align 4 | 
|  | %1 = or i32 %indvars.iv, 1 | 
|  | %arrayidx2 = getelementptr inbounds i32, i32* %f, i32 %1 | 
|  | store i32 0, i32* %arrayidx2, align 4 | 
|  | %indvars.iv.next = add nuw nsw i32 %indvars.iv, 2 | 
|  | %cmp = icmp ult i32 %indvars.iv.next, %0 | 
|  | br i1 %cmp, label %for.body, label %for.end.loopexit | 
|  |  | 
|  | for.end.loopexit:                                 ; preds = %for.body | 
|  | br label %for.end | 
|  |  | 
|  | for.end:                                          ; preds = %for.end.loopexit, %entry | 
|  | ret void | 
|  | ; CHECK-LABEL: @test( | 
|  | ; CHECK: call void @llvm.memset | 
|  | ; CHECK-NOT: store | 
|  | } | 
|  |  | 
|  | ;void test_pattern(int *f, unsigned n) { | 
|  | ;  for (unsigned i = 0; i < 2 * n; i += 2) { | 
|  | ;    f[i] = 2; | 
|  | ;    f[i+1] = 2; | 
|  | ;  } | 
|  | ;} | 
|  | define void @test_pattern(i32* %f, i32 %n) nounwind ssp { | 
|  | entry: | 
|  | %mul = shl i32 %n, 1 | 
|  | %cmp1 = icmp eq i32 %mul, 0 | 
|  | br i1 %cmp1, label %for.end, label %for.body.preheader | 
|  |  | 
|  | for.body.preheader:                               ; preds = %entry | 
|  | br label %for.body | 
|  |  | 
|  | for.body:                                         ; preds = %for.body.preheader, %for.body | 
|  | %indvars.iv = phi i32 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.body ] | 
|  | %arrayidx = getelementptr inbounds i32, i32* %f, i32 %indvars.iv | 
|  | store i32 2, i32* %arrayidx, align 4 | 
|  | %x1 = or i32 %indvars.iv, 1 | 
|  | %arrayidx2 = getelementptr inbounds i32, i32* %f, i32 %x1 | 
|  | store i32 2, i32* %arrayidx2, align 4 | 
|  | %indvars.iv.next = add nuw nsw i32 %indvars.iv, 2 | 
|  | %cmp = icmp ult i32 %indvars.iv.next, %mul | 
|  | br i1 %cmp, label %for.body, label %for.end.loopexit | 
|  |  | 
|  | for.end.loopexit:                                 ; preds = %for.body | 
|  | br label %for.end | 
|  |  | 
|  | for.end:                                          ; preds = %for.end.loopexit, %entry | 
|  | ret void | 
|  | ; CHECK-LABEL: @test_pattern( | 
|  | ; CHECK: call void @memset_pattern16 | 
|  | ; CHECK-NOT: store | 
|  | } |