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

61 lines
2.8 KiB
LLVM

; REQUIRES: asserts
; RUN: opt -passes=loop-vectorize -debug-only=loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -vplan-print-in-dot-format -disable-output %s 2>&1 | 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"
; Verify that -vplan-print-in-dot-format option works.
define void @print_call_and_memory(i64 %n, ptr noalias %y, ptr noalias %x) nounwind uwtable {
; CHECK: digraph VPlan {
; CHECK-NEXT: graph [labelloc=t, fontsize=30; label="Vectorization Plan\nInitial VPlan for VF=\{4\},UF\>=1"]
; CHECK-NEXT: node [shape=rect, fontname=Courier, fontsize=30]
; CHECK-NEXT: edge [fontname=Courier, fontsize=30]
; CHECK-NEXT: compound=true
; CHECK-NEXT: N0 [label =
; CHECK-NEXT: "ph:\l" +
; CHECK-NEXT: "No successors\l"
; CHECK-NEXT: ]
; CHECK-NEXT: N1 [label =
; CHECK-NEXT: "vector.ph:\l" +
; CHECK-NEXT: "Successor(s): vector loop\l"
; CHECK-NEXT: ]
; CHECK-NEXT: N1 -> N2 [ label="" lhead=cluster_N3]
; CHECK-NEXT: subgraph cluster_N3 {
; CHECK-NEXT: fontname=Courier
; CHECK-NEXT: label="\<x1\> vector loop"
; CHECK-NEXT: N2 [label =
; CHECK-NEXT: "vector.body:\l" +
; CHECK-NEXT: " EMIT vp\<[[CAN_IV:%.+]]\> = CANONICAL-INDUCTION\l" +
; CHECK-NEXT: " vp\<[[STEPS:%.+]]\> = SCALAR-STEPS vp\<[[CAN_IV]]\>, ir\<1\>\l" +
; CHECK-NEXT: " CLONE ir\<%arrayidx\> = getelementptr ir\<%y\>, vp\<[[STEPS]]\>\l" +
; CHECK-NEXT: " WIDEN ir\<%lv\> = load ir\<%arrayidx\>\l" +
; CHECK-NEXT: " WIDEN-CALL ir\<%call\> = call @llvm.sqrt.f32(ir\<%lv\>) (using vector intrinsic)\l" +
; CHECK-NEXT: " CLONE ir\<%arrayidx2\> = getelementptr ir\<%x\>, vp\<[[STEPS]]\>\l" +
; CHECK-NEXT: " WIDEN store ir\<%arrayidx2\>, ir\<%call\>\l" +
; CHECK-NEXT: " EMIT vp\<[[CAN_IV_NEXT:%.+]]\> = VF * UF +(nuw) vp\<[[CAN_IV]]\>\l" +
; CHECK-NEXT: " EMIT branch-on-count vp\<[[CAN_IV_NEXT]]\> vp\<{{.+}}\>\l" +
; CHECK-NEXT: "No successors\l"
; CHECK-NEXT: ]
;
entry:
%cmp6 = icmp sgt i64 %n, 0
br i1 %cmp6, label %for.body, label %for.end
for.body: ; preds = %entry, %for.body
%iv = phi i64 [ %iv.next, %for.body ], [ 0, %entry ]
%arrayidx = getelementptr inbounds float, ptr %y, i64 %iv
%lv = load float, ptr %arrayidx, align 4
%call = tail call float @llvm.sqrt.f32(float %lv) nounwind readnone
%arrayidx2 = getelementptr inbounds float, ptr %x, i64 %iv
store float %call, ptr %arrayidx2, align 4
%iv.next = add i64 %iv, 1
%exitcond = icmp eq i64 %iv.next, %n
br i1 %exitcond, label %for.end, label %for.body
for.end: ; preds = %for.body, %entry
ret void
}
declare float @llvm.sqrt.f32(float) nounwind readnone