[SLP]Small buidlvector only graph should contains scalars from same block

If the graph is small and has single buildvector node, all scalars
instructions must be from the same basic block to prevent compiler
crash.

Fixes #113451

Author: alexey-bataev

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -11588,7 +11588,8 @@ bool BoUpSLP::isTreeTinyAndNotFullyVectorizable(bool ForReduction) const {
 
   if (VectorizableTree.back()->isGather() &&
       VectorizableTree.back()->isAltShuffle() &&
-      VectorizableTree.back()->getVectorFactor() > 2)
+      VectorizableTree.back()->getVectorFactor() > 2 &&
+      allSameBlock(VectorizableTree.back()->Scalars))
     return false;
 
   assert(VectorizableTree.empty()

llvm/test/Transforms/SLPVectorizer/X86/small-graph-diff-block-instructions.ll

@@ -0,0 +1,33 @@
+; 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 -mattr=+avx512dq -slp-threshold=-99999 < %s | FileCheck %s
+
+define i32 @test(i32 %arg, i32 %arg1) {
+; CHECK-LABEL: define i32 @test(
+; CHECK-SAME: i32 [[ARG:%.*]], i32 [[ARG1:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[BB:.*:]]
+; CHECK-NEXT:    [[ZEXT:%.*]] = zext i32 [[ARG1]] to i64
+; CHECK-NEXT:    [[ZEXT2:%.*]] = zext i32 [[ARG]] to i64
+; CHECK-NEXT:    [[SEXT:%.*]] = sext i32 [[ARG]] to i64
+; CHECK-NEXT:    br label %[[BB3:.*]]
+; CHECK:       [[BB3]]:
+; CHECK-NEXT:    [[GETELEMENTPTR:%.*]] = getelementptr i64, ptr addrspace(1) null, i64 [[ZEXT]]
+; CHECK-NEXT:    [[GETELEMENTPTR4:%.*]] = getelementptr i64, ptr addrspace(1) null, i64 [[ZEXT2]]
+; CHECK-NEXT:    [[GETELEMENTPTR5:%.*]] = getelementptr i64, ptr addrspace(1) null, i64 [[SEXT]]
+; CHECK-NEXT:    [[ZEXT6:%.*]] = zext i32 0 to i64
+; CHECK-NEXT:    [[GETELEMENTPTR7:%.*]] = getelementptr i64, ptr addrspace(1) null, i64 [[ZEXT6]]
+; CHECK-NEXT:    ret i32 0
+;
+bb:
+  %zext = zext i32 %arg1 to i64
+  %zext2 = zext i32 %arg to i64
+  %sext = sext i32 %arg to i64
+  br label %bb3
+
+bb3:
+  %getelementptr = getelementptr i64, ptr addrspace(1) null, i64 %zext
+  %getelementptr4 = getelementptr i64, ptr addrspace(1) null, i64 %zext2
+  %getelementptr5 = getelementptr i64, ptr addrspace(1) null, i64 %sext
+  %zext6 = zext i32 0 to i64
+  %getelementptr7 = getelementptr i64, ptr addrspace(1) null, i64 %zext6
+  ret i32 0
+}