1 ; RUN: opt -S -loop-reduce < %s | FileCheck %s 2 ; Complex addressing mode are costly. 3 ; Make loop-reduce prefer unscaled accesses. 4 ; On X86, reg1 + 1*reg2 has the same cost as reg1 + 8*reg2. 5 ; Therefore, LSR currently prefers to fold as much computation as possible 6 ; in the addressing mode. 7 ; <rdar://problem/16730541> 8 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" 9 target triple = "x86_64-apple-macosx" 10 11 define void @mulDouble(double* nocapture %a, double* nocapture %b, double* nocapture %c) { 12 ; CHECK: @mulDouble 13 entry: 14 br label %for.body 15 16 for.body: ; preds = %for.body, %entry 17 ; CHECK: [[IV:%[^ ]+]] = phi i64 [ [[IVNEXT:%[^,]+]], %for.body ], [ 0, %entry ] 18 ; Only one induction variable should have been generated. 19 ; CHECK-NOT: phi 20 %indvars.iv = phi i64 [ 1, %entry ], [ %indvars.iv.next, %for.body ] 21 %tmp = add nsw i64 %indvars.iv, -1 22 %arrayidx = getelementptr inbounds double* %b, i64 %tmp 23 %tmp1 = load double* %arrayidx, align 8 24 ; The induction variable should carry the scaling factor: 1. 25 ; CHECK: [[IVNEXT]] = add nuw nsw i64 [[IV]], 1 26 %indvars.iv.next = add i64 %indvars.iv, 1 27 %arrayidx2 = getelementptr inbounds double* %c, i64 %indvars.iv.next 28 %tmp2 = load double* %arrayidx2, align 8 29 %mul = fmul double %tmp1, %tmp2 30 %arrayidx4 = getelementptr inbounds double* %a, i64 %indvars.iv 31 store double %mul, double* %arrayidx4, align 8 32 %lftr.wideiv = trunc i64 %indvars.iv.next to i32 33 ; Comparison should be 19 * 1 = 19. 34 ; CHECK: icmp eq i32 {{%[^,]+}}, 19 35 %exitcond = icmp eq i32 %lftr.wideiv, 20 36 br i1 %exitcond, label %for.end, label %for.body 37 38 for.end: ; preds = %for.body 39 ret void 40 } 41
