llvm-for-llvmta/test/Transforms/LoopVectorize/reverse_iter.ll

46 lines
1.5 KiB
LLVM

; RUN: opt < %s -loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -dce -instcombine -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"
; PR15882: This test ensures that we do not produce wrapping arithmetic when
; creating constant reverse step vectors.
;
; int foo(int n, int *A) {
; int sum;
; for (int i=n; i > 0; i--)
; sum += A[i*2];
; return sum;
; }
;
;CHECK-LABEL: @foo(
;CHECK: <i32 0, i32 -1, i32 -2, i32 -3>
;CHECK: ret
define i32 @foo(i32 %n, i32* nocapture %A) {
%1 = icmp sgt i32 %n, 0
br i1 %1, label %.lr.ph, label %._crit_edge
.lr.ph: ; preds = %0
%2 = sext i32 %n to i64
br label %3
; <label>:3 ; preds = %.lr.ph, %3
%indvars.iv = phi i64 [ %2, %.lr.ph ], [ %indvars.iv.next, %3 ]
%sum.01 = phi i32 [ undef, %.lr.ph ], [ %9, %3 ]
%4 = trunc i64 %indvars.iv to i32
%5 = shl nsw i32 %4, 1
%6 = sext i32 %5 to i64
%7 = getelementptr inbounds i32, i32* %A, i64 %6
%8 = load i32, i32* %7, align 4
%9 = add nsw i32 %8, %sum.01
%indvars.iv.next = add i64 %indvars.iv, -1
%10 = trunc i64 %indvars.iv.next to i32
%11 = icmp sgt i32 %10, 0
br i1 %11, label %3, label %._crit_edge
._crit_edge: ; preds = %3, %0
%sum.0.lcssa = phi i32 [ undef, %0 ], [ %9, %3 ]
ret i32 %sum.0.lcssa
}