Revert "[SLP] Check if the user node has state before trying getting main instruction/opcode"

This reverts commit c9cea24fe68e24750b2d479144f839e1c2ec9d2b.

This is being reverted as it is intermixed with another commit
(898bba311f180ed54de33dc09e7071c279a4942a) that needs to be reverted.
diff --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 44dc43d..0adad5a 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -6861,7 +6861,7 @@
     return std::move(ResOrder);
   }
   if (TE.State == TreeEntry::StridedVectorize && !TopToBottom &&
-      (!TE.UserTreeIndex || !TE.UserTreeIndex.UserTE->hasState() ||
+      (!TE.UserTreeIndex ||
        !Instruction::isBinaryOp(TE.UserTreeIndex.UserTE->getOpcode())) &&
       (TE.ReorderIndices.empty() || isReverseOrder(TE.ReorderIndices)))
     return std::nullopt;
@@ -15704,8 +15704,7 @@
   const BasicBlock *TEInsertBlock = nullptr;
   // Main node of PHI entries keeps the correct order of operands/incoming
   // blocks.
-  if (auto *PHI = dyn_cast_or_null<PHINode>(
-          TEUseEI.UserTE->hasState() ? TEUseEI.UserTE->getMainOp() : nullptr);
+  if (auto *PHI = dyn_cast<PHINode>(TEUseEI.UserTE->getMainOp());
       PHI && TEUseEI.UserTE->State != TreeEntry::SplitVectorize) {
     TEInsertBlock = PHI->getIncomingBlock(TEUseEI.EdgeIdx);
     TEInsertPt = TEInsertBlock->getTerminator();
@@ -15804,8 +15803,7 @@
              "Expected only single user of a gather node.");
       const EdgeInfo &UseEI = TEPtr->UserTreeIndex;
 
-      PHINode *UserPHI = (UseEI.UserTE->State != TreeEntry::SplitVectorize &&
-                          UseEI.UserTE->hasState())
+      PHINode *UserPHI = UseEI.UserTE->State != TreeEntry::SplitVectorize
                              ? dyn_cast<PHINode>(UseEI.UserTE->getMainOp())
                              : nullptr;
       Instruction *InsertPt =
@@ -15818,8 +15816,7 @@
              TEUseEI.UserTE->isAltShuffle()) &&
             all_of(TEUseEI.UserTE->Scalars, isUsedOutsideBlock)) {
           if (UseEI.UserTE->State != TreeEntry::Vectorize ||
-              (UseEI.UserTE->hasState() &&
-               UseEI.UserTE->getOpcode() == Instruction::PHI &&
+              (UseEI.UserTE->getOpcode() == Instruction::PHI &&
                !UseEI.UserTE->isAltShuffle()) ||
               !all_of(UseEI.UserTE->Scalars, isUsedOutsideBlock))
             continue;
@@ -16441,31 +16438,24 @@
   // Get the basic block this bundle is in. All instructions in the bundle
   // should be in this block (except for extractelement-like instructions with
   // constant indices or gathered loads or copyables).
-  Instruction *Front;
-  unsigned Opcode;
-  if (E->hasState()) {
-    Front = E->getMainOp();
-    Opcode = E->getOpcode();
-  } else {
-    Front = cast<Instruction>(*find_if(E->Scalars, IsaPred<Instruction>));
-    Opcode = Front->getOpcode();
-  }
+  auto *Front = E->getMainOp();
   auto *BB = Front->getParent();
-  assert(
-      ((GatheredLoadsEntriesFirst.has_value() && Opcode == Instruction::Load &&
-        E->isGather() && E->Idx < *GatheredLoadsEntriesFirst) ||
-       E->State == TreeEntry::SplitVectorize || E->hasCopyableElements() ||
-       all_of(E->Scalars,
-              [=](Value *V) -> bool {
-                if (Opcode == Instruction::GetElementPtr &&
-                    !isa<GetElementPtrInst>(V))
-                  return true;
-                auto *I = dyn_cast<Instruction>(V);
-                return !I || !E->getMatchingMainOpOrAltOp(I) ||
-                       I->getParent() == BB || isVectorLikeInstWithConstOps(I);
-              })) &&
-      "Expected gathered loads or GEPs or instructions from same basic "
-      "block.");
+  assert(((GatheredLoadsEntriesFirst.has_value() &&
+           E->getOpcode() == Instruction::Load && E->isGather() &&
+           E->Idx < *GatheredLoadsEntriesFirst) ||
+          E->State == TreeEntry::SplitVectorize || E->hasCopyableElements() ||
+          all_of(E->Scalars,
+                 [=](Value *V) -> bool {
+                   if (E->getOpcode() == Instruction::GetElementPtr &&
+                       !isa<GetElementPtrInst>(V))
+                     return true;
+                   auto *I = dyn_cast<Instruction>(V);
+                   return !I || !E->getMatchingMainOpOrAltOp(I) ||
+                          I->getParent() == BB ||
+                          isVectorLikeInstWithConstOps(I);
+                 })) &&
+         "Expected gathered loads or GEPs or instructions from same basic "
+         "block.");
 
   auto FindLastInst = [&]() {
     Instruction *LastInst = Front;
@@ -16480,13 +16470,13 @@
           LastInst = I;
         continue;
       }
-      assert(((Opcode == Instruction::GetElementPtr &&
+      assert(((E->getOpcode() == Instruction::GetElementPtr &&
                !isa<GetElementPtrInst>(I)) ||
               E->State == TreeEntry::SplitVectorize ||
               (isVectorLikeInstWithConstOps(LastInst) &&
                isVectorLikeInstWithConstOps(I)) ||
               (GatheredLoadsEntriesFirst.has_value() &&
-               Opcode == Instruction::Load && E->isGather() &&
+               E->getOpcode() == Instruction::Load && E->isGather() &&
                E->Idx < *GatheredLoadsEntriesFirst)) &&
              "Expected vector-like or non-GEP in GEP node insts only.");
       if (!DT->isReachableFromEntry(LastInst->getParent())) {
@@ -16522,11 +16512,11 @@
           FirstInst = I;
         continue;
       }
-      assert(((Opcode == Instruction::GetElementPtr &&
-               !isa<GetElementPtrInst>(I)) ||
-              (isVectorLikeInstWithConstOps(FirstInst) &&
-               isVectorLikeInstWithConstOps(I))) &&
-             "Expected vector-like or non-GEP in GEP node insts only.");
+      assert(((E->getOpcode() == Instruction::GetElementPtr &&
+              !isa<GetElementPtrInst>(I)) ||
+             (isVectorLikeInstWithConstOps(FirstInst) &&
+              isVectorLikeInstWithConstOps(I))) &&
+                 "Expected vector-like or non-GEP in GEP node insts only.");
       if (!DT->isReachableFromEntry(FirstInst->getParent())) {
         FirstInst = I;
         continue;
@@ -16564,7 +16554,7 @@
   // Set insertpoint for gathered loads to the very first load.
   if (GatheredLoadsEntriesFirst.has_value() &&
       E->Idx >= *GatheredLoadsEntriesFirst && !E->isGather() &&
-      Opcode == Instruction::Load) {
+      E->getOpcode() == Instruction::Load) {
     Res = FindFirstInst();
     EntryToLastInstruction.try_emplace(E, Res);
     return *Res;
@@ -16596,7 +16586,7 @@
   };
   const ScheduleBundle *Bundle = FindScheduleBundle(E);
   if (!E->isGather() && !Bundle) {
-    if ((Opcode == Instruction::GetElementPtr &&
+    if ((E->getOpcode() == Instruction::GetElementPtr &&
          any_of(E->Scalars,
                 [](Value *V) {
                   return !isa<GetElementPtrInst>(V) && isa<Instruction>(V);
@@ -21011,10 +21001,9 @@
                     if (!isa<CastInst, BinaryOperator, FreezeInst, PHINode,
                              SelectInst>(U) ||
                         isa<SIToFPInst, UIToFPInst>(U) ||
-                        (UserTE->hasState() &&
-                         (!isa<CastInst, BinaryOperator, FreezeInst, PHINode,
-                               SelectInst>(UserTE->getMainOp()) ||
-                          isa<SIToFPInst, UIToFPInst>(UserTE->getMainOp()))))
+                        !isa<CastInst, BinaryOperator, FreezeInst, PHINode,
+                             SelectInst>(UserTE->getMainOp()) ||
+                        isa<SIToFPInst, UIToFPInst>(UserTE->getMainOp()))
                       return true;
                     unsigned UserTESz = DL->getTypeSizeInBits(
                         UserTE->Scalars.front()->getType());
@@ -21264,7 +21253,6 @@
           NodeIdx < VectorizableTree.size() &&
           VectorizableTree[NodeIdx]->UserTreeIndex &&
           VectorizableTree[NodeIdx]->UserTreeIndex.EdgeIdx == 0 &&
-          VectorizableTree[NodeIdx]->UserTreeIndex.UserTE->hasState() &&
           VectorizableTree[NodeIdx]->UserTreeIndex.UserTE->getOpcode() ==
               Instruction::Trunc &&
           !VectorizableTree[NodeIdx]->UserTreeIndex.UserTE->isAltShuffle();
diff --git a/llvm/test/Transforms/SLPVectorizer/X86/user-node-no-state.ll b/llvm/test/Transforms/SLPVectorizer/X86/user-node-no-state.ll
deleted file mode 100644
index 237f308..0000000
--- a/llvm/test/Transforms/SLPVectorizer/X86/user-node-no-state.ll
+++ /dev/null
@@ -1,48 +0,0 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
-; RUN: opt -S --passes=slp-vectorizer -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
-
-@g = global [128 x i8] zeroinitializer, align 16
-
-define i64 @test() {
-; CHECK-LABEL: define i64 @test() {
-; CHECK-NEXT:  [[ENTRY:.*:]]
-; CHECK-NEXT:    [[TMP0:%.*]] = load i64, ptr @g, align 8
-; CHECK-NEXT:    br label %[[FUNC_154_EXIT_FUNC_146_EXIT_CRIT_EDGE_I:.*]]
-; CHECK:       [[FUNC_154_EXIT_FUNC_146_EXIT_CRIT_EDGE_I]]:
-; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 80), align 16
-; CHECK-NEXT:    [[TMP2:%.*]] = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 88), align 8
-; CHECK-NEXT:    [[TMP3:%.*]] = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 32), align 16
-; CHECK-NEXT:    [[TMP4:%.*]] = load i64, ptr @g, align 16
-; CHECK-NEXT:    [[TMP5:%.*]] = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 8), align 8
-; CHECK-NEXT:    [[TMP6:%.*]] = load i64, ptr @g, align 16
-; CHECK-NEXT:    [[TMP7:%.*]] = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 24), align 8
-; CHECK-NEXT:    [[TMP8:%.*]] = xor i64 [[TMP1]], [[TMP2]]
-; CHECK-NEXT:    [[TMP9:%.*]] = xor i64 [[TMP8]], [[TMP3]]
-; CHECK-NEXT:    [[TMP10:%.*]] = xor i64 [[TMP9]], [[TMP4]]
-; CHECK-NEXT:    [[TMP11:%.*]] = xor i64 [[TMP10]], [[TMP5]]
-; CHECK-NEXT:    [[TMP12:%.*]] = xor i64 [[TMP11]], [[TMP6]]
-; CHECK-NEXT:    [[TMP13:%.*]] = xor i64 [[TMP12]], [[TMP7]]
-; CHECK-NEXT:    [[TMP14:%.*]] = xor i64 [[TMP13]], [[TMP0]]
-; CHECK-NEXT:    ret i64 [[TMP14]]
-;
-entry:
-  %0 = load i64, ptr @g, align 8
-  br label %func_154.exit.func_146.exit_crit_edge.i
-
-func_154.exit.func_146.exit_crit_edge.i:
-  %1 = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 80), align 16
-  %2 = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 88), align 8
-  %3 = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 32), align 16
-  %4 = load i64, ptr @g, align 16
-  %5 = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 8), align 8
-  %6 = load i64, ptr @g, align 16
-  %7 = load i64, ptr getelementptr inbounds nuw (i8, ptr @g, i64 24), align 8
-  %8 = xor i64 %1, %2
-  %9 = xor i64 %8, %3
-  %10 = xor i64 %9, %4
-  %11 = xor i64 %10, %5
-  %12 = xor i64 %11, %6
-  %13 = xor i64 %12, %7
-  %14 = xor i64 %13, %0
-  ret i64 %14
-}