Files
clang-p2996/llvm/test/Transforms/LoopVectorize/icmp-uniforms.ll
Florian Hahn b85a402dd8 [VPlan] Introduce new entry block to VPlan for early SCEV expansion.
This patch adds a new preheader block the VPlan to place SCEV expansions
expansions like the trip count. This preheader block is disconnected
at the moment, as the bypass blocks of the skeleton are not yet modeled
in VPlan.

The preheader block is executed before skeleton creation, so the SCEV
expansion results can be used during skeleton creation. At the moment,
the trip count expression and induction steps are expanded in the new
preheader. The remainder of SCEV expansions will be moved gradually in
the future.

D147965 will update skeleton creation to use the steps expanded in the
pre-header to fix #58811.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D147964
2023-05-04 14:00:13 +01:00

94 lines
3.3 KiB
LLVM

; REQUIRES: asserts
; RUN: opt < %s -passes=loop-vectorize,instcombine -force-vector-width=4 -force-vector-interleave=1 -debug-only=loop-vectorize -disable-output -print-after=instcombine 2>&1 | FileCheck %s
target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128"
; CHECK-LABEL: more_than_one_use
;
; PR30627. Check that a compare instruction with more than one use is not
; recognized as uniform and is vectorized.
;
; CHECK-NOT: Found uniform instruction: %cond = icmp slt i64 %i.next, %n
; CHECK: vector.body
; CHECK: %[[I:.+]] = add nuw nsw <4 x i64> %vec.ind, <i64 1, i64 1, i64 1, i64 1>
; CHECK: icmp slt <4 x i64> %[[I]], %broadcast.splat
; CHECK: br i1 {{.*}}, label %middle.block, label %vector.body
;
define i32 @more_than_one_use(ptr %a, i64 %n) {
entry:
br label %for.body
for.body:
%i = phi i64 [ %i.next, %for.body ], [ 0, %entry ]
%r = phi i32 [ %tmp3, %for.body ], [ 0, %entry ]
%i.next = add nuw nsw i64 %i, 1
%cond = icmp slt i64 %i.next, %n
%tmp0 = select i1 %cond, i64 %i.next, i64 0
%tmp1 = getelementptr inbounds i32, ptr %a, i64 %tmp0
%tmp2 = load i32, ptr %tmp1, align 8
%tmp3 = add i32 %r, %tmp2
br i1 %cond, label %for.body, label %for.end
for.end:
%tmp4 = phi i32 [ %tmp3, %for.body ]
ret i32 %tmp4
}
; Check for crash exposed by D76992.
; CHECK-LABEL: 'test'
; CHECK: VPlan 'Initial VPlan for VF={4},UF>=1' {
; CHECK-NEXT: Live-in vp<[[VEC_TC:%.+]]> = vector-trip-count
; CHECK-NEXT: Live-in vp<[[BTC:%.+]]> = backedge-taken count
; CHECK-NEXT: Live-in ir<14> = 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, ir<1>
; CHECK-NEXT: EMIT vp<[[COND:%.+]]> = icmp ule ir<%iv> vp<[[BTC]]>
; CHECK-NEXT: WIDEN ir<%cond0> = icmp ult ir<%iv>, ir<13>
; CHECK-NEXT: WIDEN-SELECT ir<%s> = select ir<%cond0>, ir<10>, ir<20>
; CHECK-NEXT: Successor(s): pred.store
; CHECK-EMPTY:
; CHECK-NEXT: <xVFxUF> pred.store: {
; CHECK-NEXT: pred.store.entry:
; CHECK-NEXT: BRANCH-ON-MASK vp<[[COND]]>
; CHECK-NEXT: Successor(s): pred.store.if, pred.store.continue
; CHECK-EMPTY:
; CHECK-NEXT: pred.store.if:
; CHECK-NEXT: vp<[[STEPS:%.+]]> = SCALAR-STEPS vp<[[CAN_IV]]>, ir<1>
; CHECK-NEXT: REPLICATE ir<%gep> = getelementptr ir<%ptr>, vp<[[STEPS]]>
; CHECK-NEXT: REPLICATE store ir<%s>, ir<%gep>
; CHECK-NEXT: Successor(s): pred.store.continue
; CHECK-EMPTY:
; CHECK-NEXT: pred.store.continue:
; CHECK-NEXT: No successors
; CHECK-NEXT: }
; CHECK-NEXT: Successor(s): loop.0
; CHECK-EMPTY:
; CHECK-NEXT: loop.0:
; CHECK-NEXT: EMIT vp<[[CAN_IV_NEXT:%.+]]> = VF * UF + vp<[[CAN_IV]]>
; CHECK-NEXT: EMIT branch-on-count vp<[[CAN_IV_NEXT]]> vp<[[VEC_TC]]>
; CHECK-NEXT: No successor
; CHECK-NEXT: }
define void @test(ptr %ptr) {
entry:
br label %loop
loop: ; preds = %loop, %entry
%iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
%cond0 = icmp ult i64 %iv, 13
%s = select i1 %cond0, i32 10, i32 20
%gep = getelementptr inbounds i32, ptr %ptr, i64 %iv
store i32 %s, ptr %gep
%iv.next = add nuw nsw i64 %iv, 1
%exitcond = icmp eq i64 %iv.next, 14
br i1 %exitcond, label %exit, label %loop
exit:
ret void
}