test/Transforms/LoopVectorize/SystemZ/mem-interleaving-costs-02.ll

; REQUIRES: asserts
; RUN: opt -mtriple=s390x-unknown-linux -mcpu=z13 -loop-vectorize \
; RUN:   -debug-only=loop-vectorize,vectorutils -max-interleave-group-factor=64\
; RUN:   -disable-output < %s 2>&1 | FileCheck %s
;
; Check that some cost estimations for interleave groups make sense.

; This loop is loading four i16 values at indices [0, 1, 2, 3], with a stride
; of 4. At VF=4, memory interleaving means loading 4 * 4 * 16 bits = 2 vector
; registers. Each of the 4 vector values must then be constructed from the
; two vector registers using one vperm each, which gives a cost of 2 + 4 = 6.
;
; CHECK: LV: Checking a loop in "fun0"
; CHECK: LV: Found an estimated cost of 6 for VF 4 For instruction:   %ld0 = load i16
; CHECK: LV: Found an estimated cost of 0 for VF 4 For instruction:   %ld1 = load i16
; CHECK: LV: Found an estimated cost of 0 for VF 4 For instruction:   %ld2 = load i16
; CHECK: LV: Found an estimated cost of 0 for VF 4 For instruction:   %ld3 = load i16
define void @fun0(i16 *%ptr, i16 *%dst) {
entry:
  br label %for.body

for.body:
  %ivptr = phi i16* [ %ptr.next, %for.body ], [ %ptr, %entry ]
  %iv = phi i64 [ %inc, %for.body ], [ 0, %entry ]
  %inc = add i64 %iv, 4
  %ptr0 = getelementptr inbounds i16, i16* %ivptr, i64 0
  %ld0 = load i16, i16* %ptr0
  %ptr1 = getelementptr inbounds i16, i16* %ivptr, i64 1
  %ld1 = load i16, i16* %ptr1
  %ptr2 = getelementptr inbounds i16, i16* %ivptr, i64 2
  %ld2 = load i16, i16* %ptr2
  %ptr3 = getelementptr inbounds i16, i16* %ivptr, i64 3
  %ld3 = load i16, i16* %ptr3
  %a1 = add i16 %ld0, %ld1
  %a2 = add i16 %a1, %ld2
  %a3 = add i16 %a2, %ld3
  %dstptr = getelementptr inbounds i16, i16* %dst, i64 %iv
  store i16 %a3, i16* %dstptr
  %ptr.next = getelementptr inbounds i16, i16* %ivptr, i64 4
  %cmp = icmp eq i64 %inc, 100
  br i1 %cmp, label %for.end, label %for.body

for.end:
  ret void
}

; This loop loads one i8 value in a stride of 3. At VF=16, this means loading
; 3 vector registers, and then constructing the vector value with two vperms,
; which gives a cost of 5.
;
; CHECK: LV: Checking a loop in "fun1"
; CHECK: LV: Found an estimated cost of 5 for VF 16 For instruction:   %ld0 = load i8
define void @fun1(i8 *%ptr, i8 *%dst) {
entry:
  br label %for.body

for.body:
  %ivptr = phi i8* [ %ptr.next, %for.body ], [ %ptr, %entry ]
  %iv = phi i64 [ %inc, %for.body ], [ 0, %entry ]
  %inc = add i64 %iv, 4
  %ptr0 = getelementptr inbounds i8, i8* %ivptr, i64 0
  %ld0 = load i8, i8* %ptr0
  %dstptr = getelementptr inbounds i8, i8* %dst, i64 %iv
  store i8 %ld0, i8* %dstptr
  %ptr.next = getelementptr inbounds i8, i8* %ivptr, i64 3
  %cmp = icmp eq i64 %inc, 100
  br i1 %cmp, label %for.end, label %for.body

for.end:
  ret void
}

; This loop is loading 4 i8 values at indexes [0, 1, 2, 3], with a stride of
; 32. At VF=2, this means loading 2 vector registers, and using 4 vperms to
; produce the vector values, which gives a cost of 6.
;
; CHECK: LV: Checking a loop in "fun2"
; CHECK: LV: Found an estimated cost of 6 for VF 2 For instruction:   %ld0 = load i8
; CHECK: LV: Found an estimated cost of 0 for VF 2 For instruction:   %ld1 = load i8
; CHECK: LV: Found an estimated cost of 0 for VF 2 For instruction:   %ld2 = load i8
; CHECK: LV: Found an estimated cost of 0 for VF 2 For instruction:   %ld3 = load i8
define void @fun2(i8 *%ptr, i8 *%dst) {
entry:
  br label %for.body

for.body:
  %ivptr = phi i8* [ %ptr.next, %for.body ], [ %ptr, %entry ]
  %iv = phi i64 [ %inc, %for.body ], [ 0, %entry ]
  %inc = add i64 %iv, 4
  %ptr0 = getelementptr inbounds i8, i8* %ivptr, i64 0
  %ld0 = load i8, i8* %ptr0
  %ptr1 = getelementptr inbounds i8, i8* %ivptr, i64 1
  %ld1 = load i8, i8* %ptr1
  %ptr2 = getelementptr inbounds i8, i8* %ivptr, i64 2
  %ld2 = load i8, i8* %ptr2
  %ptr3 = getelementptr inbounds i8, i8* %ivptr, i64 3
  %ld3 = load i8, i8* %ptr3
  %a1 = add i8 %ld0, %ld1
  %a2 = add i8 %a1, %ld2
  %a3 = add i8 %a2, %ld3
  %dstptr = getelementptr inbounds i8, i8* %dst, i64 %iv
  store i8 %a3, i8* %dstptr
  %ptr.next = getelementptr inbounds i8, i8* %ivptr, i64 32
  %cmp = icmp eq i64 %inc, 100
  br i1 %cmp, label %for.end, label %for.body

for.end:
  ret void
}

; This loop is loading 4 i8 values at indexes [0, 1, 2, 3], with a stride of
; 30. At VF=2, this means loading 3 vector registers, and using 4 vperms to
; produce the vector values, which gives a cost of 7. This is the same loop
; as in fun2, except the stride makes the second iterations values overlap a
; vector register boundary.
;
; CHECK: LV: Checking a loop in "fun3"
; CHECK: LV: Found an estimated cost of 7 for VF 2 For instruction:   %ld0 = load i8
; CHECK: LV: Found an estimated cost of 0 for VF 2 For instruction:   %ld1 = load i8
; CHECK: LV: Found an estimated cost of 0 for VF 2 For instruction:   %ld2 = load i8
; CHECK: LV: Found an estimated cost of 0 for VF 2 For instruction:   %ld3 = load i8
define void @fun3(i8 *%ptr, i8 *%dst) {
entry:
  br label %for.body

for.body:
  %ivptr = phi i8* [ %ptr.next, %for.body ], [ %ptr, %entry ]
  %iv = phi i64 [ %inc, %for.body ], [ 0, %entry ]
  %inc = add i64 %iv, 4
  %ptr0 = getelementptr inbounds i8, i8* %ivptr, i64 0
  %ld0 = load i8, i8* %ptr0
  %ptr1 = getelementptr inbounds i8, i8* %ivptr, i64 1
  %ld1 = load i8, i8* %ptr1
  %ptr2 = getelementptr inbounds i8, i8* %ivptr, i64 2
  %ld2 = load i8, i8* %ptr2
  %ptr3 = getelementptr inbounds i8, i8* %ivptr, i64 3
  %ld3 = load i8, i8* %ptr3
  %a1 = add i8 %ld0, %ld1
  %a2 = add i8 %a1, %ld2
  %a3 = add i8 %a2, %ld3
  %dstptr = getelementptr inbounds i8, i8* %dst, i64 %iv
  store i8 %a3, i8* %dstptr
  %ptr.next = getelementptr inbounds i8, i8* %ivptr, i64 30
  %cmp = icmp eq i64 %inc, 100
  br i1 %cmp, label %for.end, label %for.body

for.end:
  ret void
}