Files
clang-p2996/llvm/test/Transforms/LoopVectorize/vplan-iv-transforms.ll
Florian Hahn a5891fa4d2 [VPlan] Initial modeling of VF * UF as VPValue. (#74761)
This patch starts initial modeling of VF * UF in VPlan.
Initially, introduce a dedicated VFxUF VPValue, which is then
populated during VPlan::prepareToExecute. Initially, the VF * UF
applies only to the main vector loop region. Once we extend the
scope of VPlan in the future, we may want to associate different VFxUFs
with different vector loop regions (e.g. the epilogue vector loop)

This allows explicitly parameterizing recipes that rely on the
VF * UF, like the canonical induction increment. At the moment, this
mainly helps to avoid generating some duplicated calls to vscale with
scalable vectors. It should also allow using EVL as induction increments
explicitly in D99750. Referring to VF * UF is also needed in other
places that we plan to migrate to VPlan, like the minimum trip count
check during skeleton creation.

The first version creates the value for VF * UF directly in
prepareToExecute to limit the scope of the patch. A follow-on patch will
model VF * UF computation explicitly in VPlan using recipes.

Moved from Phabricator (https://reviews.llvm.org/D157322)
2023-12-08 18:30:30 +00:00

49 lines
1.7 KiB
LLVM

; REQUIRES: asserts
; RUN: opt -passes=loop-vectorize -force-vector-interleave=1 -force-vector-width=8 -S -debug %s 2>&1 | FileCheck %s
define void @iv_no_binary_op_in_descriptor(i1 %c, ptr %dst) {
; CHECK-LABEL: LV: Checking a loop in 'iv_no_binary_op_in_descriptor'
; CHECK: VPlan 'Initial VPlan for VF={8},UF>=1' {
; CHECK-NEXT: Live-in vp<[[VFxUF:%.+]]> = VF * UF
; CHECK-NEXT: Live-in vp<[[VEC_TC:%.+]]> = vector-trip-count
; CHECK-NEXT: Live-in ir<1000> = original trip-count
; CHECK-EMPTY:
; CHECK-NEXT: vector.ph:
; CHECK-NEXT: Successor(s): vector loop
; CHECK-EMPTY:
; CHECK-NEXT: <x1> vector loop: {
; CHECK-NEXT: vector.body:
; CHECK-NEXT: EMIT vp<[[CAN_IV:%.+]]> = CANONICAL-INDUCTION
; CHECK-NEXT: WIDEN-INDUCTION %iv = phi 0, %iv.next.p, ir<1>
; CHECK-NEXT: vp<[[STEPS:%.+]]> = SCALAR-STEPS vp<[[CAN_IV]]>, ir<1>
; CHECK-NEXT: CLONE ir<%gep> = getelementptr inbounds ir<%dst>, vp<[[STEPS:%.+]]>
; CHECK-NEXT: WIDEN store ir<%gep>, ir<%iv>
; CHECK-NEXT: EMIT vp<[[CAN_INC:%.+]]> = add nuw vp<[[CAN_IV]]>, vp<[[VFxUF]]>
; CHECK-NEXT: EMIT branch-on-count vp<[[CAN_INC]]>, vp<[[VEC_TC]]>
; CHECK-NEXT: No successors
; CHECK-NEXT: }
; CHECK-NEXT: Successor(s): middle.block
; CHECK-EMPTY:
; CHECK-NEXT: middle.block:
; CHECK-NEXT: No successors
; CHECK-NEXT: }
;
entry:
br label %loop.header
loop.header:
%iv = phi i64 [ 0, %entry ], [ %iv.next.p, %loop.latch ]
%gep = getelementptr inbounds i64, ptr %dst, i64 %iv
store i64 %iv, ptr %gep, align 8
%iv.next = add i64 %iv, 1
br label %loop.latch
loop.latch:
%iv.next.p = phi i64 [ %iv.next, %loop.header ]
%exitcond.not = icmp eq i64 %iv.next.p, 1000
br i1 %exitcond.not, label %exit, label %loop.header
exit:
ret void
}