[SLP]Check if vector user exist before accessing it

Need to check if vector user exist before accessing it to avoid compiler
crash.
Fixes llvm#126581

Author: alexey-bataev

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -18467,8 +18467,8 @@ void BoUpSLP::computeMinimumValueSizes() {
           any_of(
               VectorizableTree[NodeIdx]->UserTreeIndices,
               [&](const EdgeInfo &EI) {
-                return (EI.UserTE->hasState() &&
-                        EI.UserTE->getOpcode() == Instruction::ICmp) &&
+                return EI.UserTE && EI.UserTE->hasState() &&
+                       EI.UserTE->getOpcode() == Instruction::ICmp &&
                        any_of(EI.UserTE->Scalars, [&](Value *V) {
                          auto *IC = dyn_cast<ICmpInst>(V);
                          return IC &&

llvm/test/Transforms/SLPVectorizer/RISCV/check-node-without-vector-user.ll

@@ -0,0 +1,76 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S --passes=slp-vectorizer -mtriple=riscv64-unknown-linux-gnu -mattr=+v < %s | FileCheck %s
+
+@r = external global [8 x i8]
+
+define void @test(i64 %0, ptr %1) {
+; CHECK-LABEL: define void @test(
+; CHECK-SAME: i64 [[TMP0:%.*]], ptr [[TMP1:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:    [[TMP3:%.*]] = load i8, ptr @r, align 1
+; CHECK-NEXT:    [[TMP4:%.*]] = trunc i8 [[TMP3]] to i1
+; CHECK-NEXT:    [[TMP5:%.*]] = select i1 [[TMP4]], i64 [[TMP0]], i64 0
+; CHECK-NEXT:    [[TMP6:%.*]] = getelementptr i8, ptr @r, i64 [[TMP5]]
+; CHECK-NEXT:    [[TMP7:%.*]] = load i8, ptr [[TMP6]], align 1
+; CHECK-NEXT:    [[TMP8:%.*]] = icmp ule i8 [[TMP3]], [[TMP7]]
+; CHECK-NEXT:    [[TMP9:%.*]] = sext i1 [[TMP8]] to i32
+; CHECK-NEXT:    [[TMP10:%.*]] = load i8, ptr getelementptr (i8, ptr @r, i64 -8049), align 1
+; CHECK-NEXT:    [[TMP11:%.*]] = trunc i8 [[TMP10]] to i1
+; CHECK-NEXT:    [[TMP12:%.*]] = select i1 [[TMP11]], i64 [[TMP0]], i64 0
+; CHECK-NEXT:    [[TMP13:%.*]] = getelementptr i8, ptr @r, i64 [[TMP12]]
+; CHECK-NEXT:    [[TMP14:%.*]] = load i8, ptr [[TMP13]], align 1
+; CHECK-NEXT:    [[TMP15:%.*]] = icmp ule i8 [[TMP10]], [[TMP14]]
+; CHECK-NEXT:    [[TMP16:%.*]] = sext i1 [[TMP15]] to i32
+; CHECK-NEXT:    [[TMP17:%.*]] = add i32 [[TMP9]], [[TMP16]]
+; CHECK-NEXT:    [[TMP18:%.*]] = load i8, ptr getelementptr (i8, ptr @r, i64 -16098), align 1
+; CHECK-NEXT:    [[TMP19:%.*]] = trunc i8 [[TMP18]] to i1
+; CHECK-NEXT:    [[TMP20:%.*]] = select i1 [[TMP19]], i64 [[TMP0]], i64 0
+; CHECK-NEXT:    [[TMP21:%.*]] = getelementptr i8, ptr @r, i64 [[TMP20]]
+; CHECK-NEXT:    [[TMP22:%.*]] = load i8, ptr [[TMP21]], align 1
+; CHECK-NEXT:    [[TMP23:%.*]] = icmp ule i8 [[TMP18]], [[TMP22]]
+; CHECK-NEXT:    [[TMP24:%.*]] = sext i1 [[TMP23]] to i32
+; CHECK-NEXT:    [[TMP25:%.*]] = add i32 [[TMP17]], [[TMP24]]
+; CHECK-NEXT:    [[TMP26:%.*]] = load i8, ptr getelementptr (i8, ptr @r, i64 -24147), align 1
+; CHECK-NEXT:    [[TMP27:%.*]] = trunc i8 [[TMP26]] to i1
+; CHECK-NEXT:    [[TMP28:%.*]] = select i1 [[TMP27]], i64 [[TMP0]], i64 0
+; CHECK-NEXT:    [[TMP29:%.*]] = getelementptr i8, ptr @r, i64 [[TMP28]]
+; CHECK-NEXT:    [[TMP30:%.*]] = load i8, ptr [[TMP29]], align 1
+; CHECK-NEXT:    [[TMP31:%.*]] = icmp ule i8 [[TMP26]], [[TMP30]]
+; CHECK-NEXT:    [[TMP32:%.*]] = sext i1 [[TMP31]] to i32
+; CHECK-NEXT:    [[TMP33:%.*]] = add i32 [[TMP25]], [[TMP32]]
+; CHECK-NEXT:    store i32 [[TMP33]], ptr [[TMP1]], align 4
+; CHECK-NEXT:    ret void
+;
+  %3 = load i8, ptr @r, align 1
+  %4 = trunc i8 %3 to i1
+  %5 = select i1 %4, i64 %0, i64 0
+  %6 = getelementptr i8, ptr @r, i64 %5
+  %7 = load i8, ptr %6, align 1
+  %8 = icmp ule i8 %3, %7
+  %9 = sext i1 %8 to i32
+  %10 = load i8, ptr getelementptr (i8, ptr @r, i64 -8049), align 1
+  %11 = trunc i8 %10 to i1
+  %12 = select i1 %11, i64 %0, i64 0
+  %13 = getelementptr i8, ptr @r, i64 %12
+  %14 = load i8, ptr %13, align 1
+  %15 = icmp ule i8 %10, %14
+  %16 = sext i1 %15 to i32
+  %17 = add i32 %9, %16
+  %18 = load i8, ptr getelementptr (i8, ptr @r, i64 -16098), align 1
+  %19 = trunc i8 %18 to i1
+  %20 = select i1 %19, i64 %0, i64 0
+  %21 = getelementptr i8, ptr @r, i64 %20
+  %22 = load i8, ptr %21, align 1
+  %23 = icmp ule i8 %18, %22
+  %24 = sext i1 %23 to i32
+  %25 = add i32 %17, %24
+  %26 = load i8, ptr getelementptr (i8, ptr @r, i64 -24147), align 1
+  %27 = trunc i8 %26 to i1
+  %28 = select i1 %27, i64 %0, i64 0
+  %29 = getelementptr i8, ptr @r, i64 %28
+  %30 = load i8, ptr %29, align 1
+  %31 = icmp ule i8 %26, %30
+  %32 = sext i1 %31 to i32
+  %33 = add i32 %25, %32
+  store i32 %33, ptr %1, align 4
+  ret void
+}