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| ; RUN: opt < %s -loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -dce -instcombine -S -enable-if-conversion | 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"
; This is kernel11 from "LivermoreLoops". We can't vectorize it because we
; access both x[k] and x[k-1].
;
; void kernel11(double *x, double *y, int n) {
; for ( int k=1 ; k<n ; k++ )
; x[k] = x[k-1] + y[k];
; }
; CHECK-LABEL: @kernel11(
; CHECK-NOT: <4 x double>
; CHECK: ret
define i32 @kernel11(double* %x, double* %y, i32 %n) nounwind uwtable ssp {
%1 = alloca double*, align 8
%2 = alloca double*, align 8
%3 = alloca i32, align 4
%k = alloca i32, align 4
store double* %x, double** %1, align 8
store double* %y, double** %2, align 8
store i32 %n, i32* %3, align 4
store i32 1, i32* %k, align 4
br label %4
; <label>:4 ; preds = %25, %0
%5 = load i32, i32* %k, align 4
%6 = load i32, i32* %3, align 4
%7 = icmp slt i32 %5, %6
br i1 %7, label %8, label %28
; <label>:8 ; preds = %4
%9 = load i32, i32* %k, align 4
%10 = sub nsw i32 %9, 1
%11 = sext i32 %10 to i64
%12 = load double*, double** %1, align 8
%13 = getelementptr inbounds double, double* %12, i64 %11
%14 = load double, double* %13, align 8
%15 = load i32, i32* %k, align 4
%16 = sext i32 %15 to i64
%17 = load double*, double** %2, align 8
%18 = getelementptr inbounds double, double* %17, i64 %16
%19 = load double, double* %18, align 8
%20 = fadd double %14, %19
%21 = load i32, i32* %k, align 4
%22 = sext i32 %21 to i64
%23 = load double*, double** %1, align 8
%24 = getelementptr inbounds double, double* %23, i64 %22
store double %20, double* %24, align 8
br label %25
; <label>:25 ; preds = %8
%26 = load i32, i32* %k, align 4
%27 = add nsw i32 %26, 1
store i32 %27, i32* %k, align 4
br label %4
; <label>:28 ; preds = %4
ret i32 0
}
; A[i*7] is scalarized, and the different scalars can in theory wrap
; around and overwrite other scalar elements. However we can still
; vectorize because we can version the loop to avoid this case.
;
; void foo(int *a) {
; for (int i=0; i<256; ++i) {
; int x = a[i*7];
; if (x>3)
; x = x*x+x*4;
; a[i*7] = x+3;
; }
; }
; CHECK-LABEL: @func2(
; CHECK: <4 x i32>
; CHECK: ret
define i32 @func2(i32* nocapture %a) nounwind uwtable ssp {
br label %1
; <label>:1 ; preds = %7, %0
%indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %7 ]
%2 = mul nsw i64 %indvars.iv, 7
%3 = getelementptr inbounds i32, i32* %a, i64 %2
%4 = load i32, i32* %3, align 4
%5 = icmp sgt i32 %4, 3
br i1 %5, label %6, label %7
; <label>:6 ; preds = %1
%tmp = add i32 %4, 4
%tmp1 = mul i32 %tmp, %4
br label %7
; <label>:7 ; preds = %6, %1
%x.0 = phi i32 [ %tmp1, %6 ], [ %4, %1 ]
%8 = add nsw i32 %x.0, 3
store i32 %8, i32* %3, 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, 256
br i1 %exitcond, label %9, label %1
; <label>:9 ; preds = %7
ret i32 0
}
|