[SLP][NFC]Add a test with truncated loads, but incorrect trunc after

minbitwidth analysis.

Author: alexey-bataev

llvm/test/Transforms/SLPVectorizer/RISCV/trunc-to-large-than-bw.ll

@@ -0,0 +1,41 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S --passes=slp-vectorizer -mtriple=riscv64-unknown-linux-gnu -mattr="+v" < %s | FileCheck %s
+
+@c = global [12 x i64] zeroinitializer
+
+define i32 @test() {
+; CHECK-LABEL: define i32 @test(
+; CHECK-SAME: ) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = call <4 x i64> @llvm.experimental.vp.strided.load.v4i64.p0.i64(ptr align 8 @c, i64 24, <4 x i1> <i1 true, i1 true, i1 true, i1 true>, i32 4)
+; CHECK-NEXT:    [[TMP1:%.*]] = trunc <4 x i64> [[TMP0]] to <4 x i16>
+; CHECK-NEXT:    [[TMP2:%.*]] = and <4 x i16> [[TMP1]], <i16 -1, i16 -1, i16 -1, i16 -1>
+; CHECK-NEXT:    [[TMP3:%.*]] = xor <4 x i16> [[TMP2]], <i16 -1, i16 -1, i16 -1, i16 -1>
+; CHECK-NEXT:    [[TMP4:%.*]] = call i16 @llvm.vector.reduce.umax.v4i16(<4 x i16> [[TMP3]])
+; CHECK-NEXT:    [[TMP5:%.*]] = zext i16 [[TMP4]] to i32
+; CHECK-NEXT:    [[TMP6:%.*]] = call i32 @llvm.umax.i32(i32 [[TMP5]], i32 1)
+; CHECK-NEXT:    ret i32 [[TMP6]]
+;
+entry:
+  %0 = load i64, ptr @c, align 8
+  %conv = trunc i64 %0 to i32
+  %conv3 = and i32 %conv, 65535
+  %conv4 = xor i32 %conv3, 65535
+  %.conv4 = tail call i32 @llvm.umax.i32(i32 1, i32 %conv4)
+  %1 = load i64, ptr getelementptr inbounds ([12 x i64], ptr @c, i64 0, i64 3), align 8
+  %conv.1 = trunc i64 %1 to i32
+  %conv3.1 = and i32 %conv.1, 65535
+  %conv4.1 = xor i32 %conv3.1, 65535
+  %.conv4.1 = tail call i32 @llvm.umax.i32(i32 %.conv4, i32 %conv4.1)
+  %2 = load i64, ptr getelementptr inbounds ([12 x i64], ptr @c, i64 0, i64 6), align 8
+  %conv.2 = trunc i64 %2 to i32
+  %conv3.2 = and i32 %conv.2, 65535
+  %conv4.2 = xor i32 %conv3.2, 65535
+  %.conv4.2 = tail call i32 @llvm.umax.i32(i32 %.conv4.1, i32 %conv4.2)
+  %3 = load i64, ptr getelementptr inbounds ([12 x i64], ptr @c, i64 0, i64 9), align 8
+  %conv.3 = trunc i64 %3 to i32
+  %conv3.3 = and i32 %conv.3, 65535
+  %conv4.3 = xor i32 %conv3.3, 65535
+  %.conv4.3 = tail call i32 @llvm.umax.i32(i32 %.conv4.2, i32 %conv4.3)
+  ret i32 %.conv4.3
+}