[LV] Remove a change that was added in D106164.

[sdesmalen]

Summary

This change wasn't strictly necessary for D106164 and could be removed.
This patch addresses the post-commit comments from @fhahn on D106164, and
also changes sve-widen-gep.ll to use the same IR test as shown in
pointer-induction.ll.

[fhahn]

LGTM, thanks!

[fhahn]

Looks like `sve-widen-gep.ll is failing in the pre-merge failures ,might be good to double check those failures before committing

llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

if (!isLoopVaryingBitCastOrGEP(Ptr))
       return;
 
     // If the pointer has already been identified as scalar (e.g., if it was
     // also identified as uniform), there's nothing to do.
     auto *I = cast<Instruction>(Ptr);
     if (Worklist.count(I))
       return;
 
-    // If all users of the pointer will be memory accesses and scalar, place the
-    // pointer in ScalarPtrs. Otherwise, place the pointer in
-    // PossibleNonScalarPtrs.
-    if (llvm::all_of(I->users(), [&](User *U) {
-          return (isa<LoadInst>(U) || isa<StoreInst>(U)) &&
-                 isScalarUse(cast<Instruction>(U), Ptr);
+    // If the use of the pointer will be a scalar use, and all users of the
+    // pointer are memory accesses, place the pointer in ScalarPtrs. Otherwise,
+    // place the pointer in PossibleNonScalarPtrs.
+    if (isScalarUse(MemAccess, Ptr) && llvm::all_of(I->users(), [&](User *U) {
+          return isa<LoadInst>(U) || isa<StoreInst>(U);
         }))
       ScalarPtrs.insert(I);
     else
       PossibleNonScalarPtrs.insert(I);
   };
 
   // We seed the scalars analysis with three classes of instructions: (1)
   // instructions marked uniform-after-vectorization and (2) bitcast,

llvm/test/Transforms/LoopVectorize/AArch64/sve-widen-gep.ll

+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; REQUIRES: asserts
 ; RUN: opt -loop-vectorize -scalable-vectorization=on -S -mtriple=aarch64 -mattr=+sve -debug-only=loop-vectorize < %s 2>&1 | FileCheck %s
 
 target triple = "aarch64-unknown-linux-gnu"
 
-; In the test below the PHI instruction:
-;  %0 = phi i8* [ %incdec.ptr190, %loop.body ], [ %src, %entry ]
-; has multiple uses, i.e.
-;  1. As a uniform address for the load, and
-;  2. Non-uniform use by the getelementptr + store, which leads to replication.
-
-; CHECK-LABEL:  LV: Checking a loop in "phi_multiple_use"
-; CHECK-NOT:    LV: Found new scalar instruction:   %incdec.ptr190 = getelementptr inbounds i8, i8* %0, i64 1
+; CHECK-LABEL:  LV: Checking a loop in "pointer_induction_used_as_vector"
+; CHECK-NOT:    LV: Found {{.*}} scalar instruction:   %ptr.iv.2.next = getelementptr inbounds i8, i8* %ptr.iv.2, i64 1
 ;
 ; CHECK:        VPlan 'Initial VPlan for VF={vscale x 2},UF>=1' {
 ; CHECK-NEXT:   loop.body:
-; CHECK-NEXT:     WIDEN-INDUCTION %index = phi 0, %index.next
-; CHECK-NEXT:     WIDEN-PHI %curchar = phi %curchar.next, %curptr
-; CHECK-NEXT:     WIDEN-PHI %0 = phi %incdec.ptr190, %src
-; CHECK-NEXT:     WIDEN-GEP Var[Inv] ir<%incdec.ptr190> = getelementptr ir<%0>, ir<1>
-; CHECK-NEXT:     WIDEN store ir<%curchar>, ir<%incdec.ptr190>
-; CHECK-NEXT:     WIDEN ir<%1> = load ir<%0>
-; CHECK-NEXT:     WIDEN ir<%2> = add ir<%1>, ir<1>
-; CHECK-NEXT:     WIDEN store ir<%0>, ir<%2>
+; CHECK-NEXT:     WIDEN-INDUCTION %iv = phi 0, %iv.next
+; CHECK-NEXT:     WIDEN-PHI %ptr.iv.1 = phi %start.1, %ptr.iv.1.next
+; CHECK-NEXT:     WIDEN-PHI %ptr.iv.2 = phi %start.2, %ptr.iv.2.next
+; CHECK-NEXT:     WIDEN-GEP Var[Inv] ir<%ptr.iv.2.next> = getelementptr ir<%ptr.iv.2>, ir<1>
+; CHECK-NEXT:     WIDEN store ir<%ptr.iv.1>, ir<%ptr.iv.2.next>
+; CHECK-NEXT:     WIDEN ir<%lv> = load ir<%ptr.iv.2>
+; CHECK-NEXT:     WIDEN ir<%add> = add ir<%lv>, ir<1>
+; CHECK-NEXT:     WIDEN store ir<%ptr.iv.2>, ir<%add>
 ; CHECK-NEXT:   No successors
 ; CHECK-NEXT:   }
 
-define void @phi_multiple_use(i8** noalias %curptr, i8* noalias %src, i64 %N) #0 {
-; CHECK-LABEL: @phi_multiple_use(
+; In the test below the pointer phi %ptr.iv.2 is used as
+;  1. As a uniform address for the load, and
+;  2. Non-uniform use by the getelementptr which is stored. This requires the
+;     vector value.
+define void @pointer_induction_used_as_vector(i8** noalias %start.1, i8* noalias %start.2, i64 %N) {
+; CHECK-LABEL: @pointer_induction_used_as_vector(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = call i64 @llvm.vscale.i64()
+; CHECK-NEXT:    [[TMP1:%.*]] = mul i64 [[TMP0]], 2
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N:%.*]], [[TMP1]]
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
+; CHECK:       vector.ph:
+; CHECK-NEXT:    [[TMP2:%.*]] = call i64 @llvm.vscale.i64()
+; CHECK-NEXT:    [[TMP3:%.*]] = mul i64 [[TMP2]], 2
+; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i64 [[N]], [[TMP3]]
+; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[N_MOD_VF]]
+; CHECK-NEXT:    [[IND_END:%.*]] = getelementptr i8*, i8** [[START_1:%.*]], i64 [[N_VEC]]
+; CHECK-NEXT:    [[IND_END3:%.*]] = getelementptr i8, i8* [[START_2:%.*]], i64 [[N_VEC]]
+; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]]
 ; CHECK:       vector.body:
-; CHECK-NEXT:    [[INDEX1:%.*]] = phi i64 [ 0, %vector.ph ], [ {{.*}}, %vector.body ]
-; CHECK-NEXT:    {{.*}} = add i64 [[INDEX1]], 0
-; CHECK-NEXT:    [[TMP1:%.*]] = add i64 [[INDEX1]], 0
-; CHECK-NEXT:    [[NEXT_GEP:%.*]] = getelementptr i8*, i8** %curptr, i64 [[TMP1]]
-; CHECK-NEXT:    [[TMP2:%.*]] = call <vscale x 2 x i64> @llvm.experimental.stepvector.nxv2i64()
-; CHECK-NEXT:    [[DOTSPLATINSERT:%.*]] = insertelement <vscale x 2 x i64> poison, i64 [[INDEX1]], i32 0
+; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
+; CHECK-NEXT:    [[TMP4:%.*]] = add i64 [[INDEX]], 0
+; CHECK-NEXT:    [[TMP5:%.*]] = add i64 [[INDEX]], 0
+; CHECK-NEXT:    [[NEXT_GEP:%.*]] = getelementptr i8*, i8** [[START_1]], i64 [[TMP5]]
+; CHECK-NEXT:    [[TMP6:%.*]] = call <vscale x 2 x i64> @llvm.experimental.stepvector.nxv2i64()
+; CHECK-NEXT:    [[DOTSPLATINSERT:%.*]] = insertelement <vscale x 2 x i64> poison, i64 [[INDEX]], i32 0
 ; CHECK-NEXT:    [[DOTSPLAT:%.*]] = shufflevector <vscale x 2 x i64> [[DOTSPLATINSERT]], <vscale x 2 x i64> poison, <vscale x 2 x i32> zeroinitializer
-; CHECK-NEXT:    [[TMP3:%.*]] = add <vscale x 2 x i64> shufflevector (<vscale x 2 x i64> insertelement (<vscale x 2 x i64> poison, i64 0, i32 0), <vscale x 2 x i64> poison, <vscale x 2 x i32> zeroinitializer), [[TMP2]]
-; CHECK-NEXT:    [[TMP4:%.*]] = add <vscale x 2 x i64> [[DOTSPLAT]], [[TMP3]]
-; CHECK-NEXT:    [[NEXT_GEP6:%.*]] = getelementptr i8, i8* %src, <vscale x 2 x i64> [[TMP4]]
-; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr inbounds i8, <vscale x 2 x i8*> [[NEXT_GEP6]], i64 1
-; CHECK:         store <vscale x 2 x i8*> [[TMP5]], <vscale x 2 x i8*>*
-; CHECK-NEXT:    [[TMP6:%.*]] = extractelement <vscale x 2 x i8*> [[NEXT_GEP6]], i32 0
-; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr i8, i8* [[TMP6]], i32 0
-; CHECK-NEXT:    [[TMP8:%.*]] = bitcast i8* [[TMP7]] to <vscale x 2 x i8>*
-; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <vscale x 2 x i8>, <vscale x 2 x i8>* [[TMP8]]
-; CHECK-NEXT:    [[TMP9:%.*]] = add <vscale x 2 x i8> [[WIDE_LOAD]],
-; CHECK:         store <vscale x 2 x i8> [[TMP9]], <vscale x 2 x i8>*
+; CHECK-NEXT:    [[TMP7:%.*]] = add <vscale x 2 x i64> shufflevector (<vscale x 2 x i64> insertelement (<vscale x 2 x i64> poison, i64 0, i32 0), <vscale x 2 x i64> poison, <vscale x 2 x i32> zeroinitializer), [[TMP6]]
+; CHECK-NEXT:    [[TMP8:%.*]] = add <vscale x 2 x i64> [[DOTSPLAT]], [[TMP7]]
+; CHECK-NEXT:    [[NEXT_GEP4:%.*]] = getelementptr i8, i8* [[START_2]], <vscale x 2 x i64> [[TMP8]]
+; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i8, <vscale x 2 x i8*> [[NEXT_GEP4]], i64 1
+; CHECK-NEXT:    [[TMP10:%.*]] = getelementptr i8*, i8** [[NEXT_GEP]], i32 0
+; CHECK-NEXT:    [[TMP11:%.*]] = bitcast i8** [[TMP10]] to <vscale x 2 x i8*>*
+; CHECK-NEXT:    store <vscale x 2 x i8*> [[TMP9]], <vscale x 2 x i8*>* [[TMP11]], align 8
+; CHECK-NEXT:    [[TMP12:%.*]] = extractelement <vscale x 2 x i8*> [[NEXT_GEP4]], i32 0
+; CHECK-NEXT:    [[TMP13:%.*]] = getelementptr i8, i8* [[TMP12]], i32 0
+; CHECK-NEXT:    [[TMP14:%.*]] = bitcast i8* [[TMP13]] to <vscale x 2 x i8>*
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <vscale x 2 x i8>, <vscale x 2 x i8>* [[TMP14]], align 1
+; CHECK-NEXT:    [[TMP15:%.*]] = add <vscale x 2 x i8> [[WIDE_LOAD]], shufflevector (<vscale x 2 x i8> insertelement (<vscale x 2 x i8> poison, i8 1, i32 0), <vscale x 2 x i8> poison, <vscale x 2 x i32> zeroinitializer)
+; CHECK-NEXT:    [[TMP16:%.*]] = bitcast i8* [[TMP13]] to <vscale x 2 x i8>*
+; CHECK-NEXT:    store <vscale x 2 x i8> [[TMP15]], <vscale x 2 x i8>* [[TMP16]], align 1
+; CHECK-NEXT:    [[TMP17:%.*]] = call i64 @llvm.vscale.i64()
+; CHECK-NEXT:    [[TMP18:%.*]] = mul i64 [[TMP17]], 2
+; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], [[TMP18]]
+; CHECK-NEXT:    [[TMP19:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[TMP19]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
+; CHECK:       middle.block:
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label [[EXIT:%.*]], label [[SCALAR_PH]]
+; CHECK:       scalar.ph:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[BC_RESUME_VAL1:%.*]] = phi i8** [ [[IND_END]], [[MIDDLE_BLOCK]] ], [ [[START_1]], [[ENTRY]] ]
+; CHECK-NEXT:    [[BC_RESUME_VAL2:%.*]] = phi i8* [ [[IND_END3]], [[MIDDLE_BLOCK]] ], [ [[START_2]], [[ENTRY]] ]
+; CHECK-NEXT:    br label [[LOOP_BODY:%.*]]
+; CHECK:       loop.body:
+; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], [[LOOP_BODY]] ]
+; CHECK-NEXT:    [[PTR_IV_1:%.*]] = phi i8** [ [[BC_RESUME_VAL1]], [[SCALAR_PH]] ], [ [[PTR_IV_1_NEXT:%.*]], [[LOOP_BODY]] ]
+; CHECK-NEXT:    [[PTR_IV_2:%.*]] = phi i8* [ [[BC_RESUME_VAL2]], [[SCALAR_PH]] ], [ [[PTR_IV_2_NEXT:%.*]], [[LOOP_BODY]] ]
+; CHECK-NEXT:    [[PTR_IV_1_NEXT]] = getelementptr inbounds i8*, i8** [[PTR_IV_1]], i64 1
+; CHECK-NEXT:    [[PTR_IV_2_NEXT]] = getelementptr inbounds i8, i8* [[PTR_IV_2]], i64 1
+; CHECK-NEXT:    store i8* [[PTR_IV_2_NEXT]], i8** [[PTR_IV_1]], align 8
+; CHECK-NEXT:    [[LV:%.*]] = load i8, i8* [[PTR_IV_2]], align 1
+; CHECK-NEXT:    [[ADD:%.*]] = add i8 [[LV]], 1
+; CHECK-NEXT:    store i8 [[ADD]], i8* [[PTR_IV_2]], align 1
+; CHECK-NEXT:    [[IV_NEXT]] = add nuw i64 [[IV]], 1
+; CHECK-NEXT:    [[C:%.*]] = icmp ne i64 [[IV_NEXT]], [[N]]
+; CHECK-NEXT:    br i1 [[C]], label [[LOOP_BODY]], label [[EXIT]], !llvm.loop [[LOOP2:![0-9]+]]
+; CHECK:       exit:
+; CHECK-NEXT:    ret void
+;
+
 
 entry:
   br label %loop.body
 
 loop.body:                                    ; preds = %loop.body, %entry
-  %index = phi i64 [ 0, %entry ], [ %index.next, %loop.body ]
-  %curchar = phi i8** [ %curchar.next, %loop.body ], [ %curptr, %entry ]
-  %0 = phi i8* [ %incdec.ptr190, %loop.body ], [ %src, %entry ]
-  %incdec.ptr190 = getelementptr inbounds i8, i8* %0, i64 1
-  %curchar.next = getelementptr inbounds i8*, i8** %curchar, i64 1
-  store i8* %incdec.ptr190, i8** %curchar, align 8
-  %1 = load i8, i8* %0, align 1
-  %2 = add i8 %1, 1
-  store i8 %2, i8* %0, align 1
-  %index.next = add nuw i64 %index, 1
-  %3 = icmp ne i64 %index.next, %N
-  br i1 %3, label %loop.body, label %exit, !llvm.loop !0
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop.body ]
+  %ptr.iv.1 = phi i8** [ %start.1, %entry ], [ %ptr.iv.1.next, %loop.body ]
+  %ptr.iv.2 = phi i8* [ %start.2, %entry ], [ %ptr.iv.2.next, %loop.body ]
+  %ptr.iv.1.next = getelementptr inbounds i8*, i8** %ptr.iv.1, i64 1
+  %ptr.iv.2.next = getelementptr inbounds i8, i8* %ptr.iv.2, i64 1
+  store i8* %ptr.iv.2.next, i8** %ptr.iv.1, align 8
+  %lv = load i8, i8* %ptr.iv.2, align 1
+  %add = add i8 %lv, 1
+  store i8 %add, i8* %ptr.iv.2, align 1
+  %iv.next = add nuw i64 %iv, 1
+  %c = icmp ne i64 %iv.next, %N
+  br i1 %c, label %loop.body, label %exit, !llvm.loop !0
 
 exit:                            ; preds = %loop.body
   ret void
 }
 
 
 attributes #0 = {"target-features"="+sve"}
 
 !0 = distinct !{!0, !1, !2, !3}
 !1 = !{!"llvm.loop.interleave.count", i32 1}
 !2 = !{!"llvm.loop.vectorize.width", i32 2}
 !3 = !{!"llvm.loop.vectorize.scalable.enable", i1 true}
 !4 = !{ !5 }
 !5 = distinct !{ !5, !6 }
 !6 = distinct !{ !7 }
 !7 = distinct !{ !7, !6 }