[SLP][NFC]Add a test for gather node with mixed load/non-load scalars.

Author: alexey-bataev

llvm/test/Transforms/SLPVectorizer/X86/remark-partial-loads-vectorize.ll

@@ -0,0 +1,49 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt < %s -passes=slp-vectorizer -S -mtriple=x86_64-unknown-linux-gnu -mcpu=skylake-avx512 -pass-remarks-output=%t | FileCheck %s
+; RUN: FileCheck --input-file=%t --check-prefix=YAML %s
+
+; YAML-LABEL: --- !Passed
+; YAML-NEXT:  Pass:            slp-vectorizer
+; YAML-NEXT:  Name:            VectorizedList
+; YAML-NEXT:  Function:        test
+; YAML-NEXT:  Args:
+; YAML-NEXT:    - String:          'SLP vectorized with cost '
+; YAML-NEXT:    - Cost:            '-2'
+; YAML-NEXT:    - String:          ' and with tree size '
+; YAML-NEXT:    - TreeSize:        '4'
+; YAML-LABEL: --- !Passed
+; YAML-NEXT:  Pass:            slp-vectorizer
+; YAML-NEXT:  Name:            VectorizedList
+; YAML-NEXT:  Function:        test
+; YAML-NEXT:  Args:
+; YAML-NEXT:    - String:          'SLP vectorized with cost '
+; YAML-NEXT:    - Cost:            '-2'
+; YAML-NEXT:    - String:          ' and with tree size '
+; YAML-NEXT:    - TreeSize:        '2'
+
+define <4 x float> @test(ptr %x, float %v, float %a) {
+; CHECK-LABEL: define <4 x float> @test(
+; CHECK-SAME: ptr [[X:%.*]], float [[V:%.*]], float [[A:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = load <2 x float>, ptr [[X]], align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <4 x float> poison, float [[A]], i32 0
+; CHECK-NEXT:    [[TMP3:%.*]] = shufflevector <4 x float> [[TMP2]], <4 x float> poison, <4 x i32> zeroinitializer
+; CHECK-NEXT:    [[TMP4:%.*]] = insertelement <4 x float> poison, float [[V]], i32 0
+; CHECK-NEXT:    [[TMP5:%.*]] = shufflevector <2 x float> [[TMP1]], <2 x float> poison, <4 x i32> <i32 0, i32 1, i32 poison, i32 poison>
+; CHECK-NEXT:    [[TMP6:%.*]] = shufflevector <4 x float> [[TMP4]], <4 x float> [[TMP5]], <4 x i32> <i32 0, i32 poison, i32 4, i32 5>
+; CHECK-NEXT:    [[TMP7:%.*]] = shufflevector <4 x float> [[TMP6]], <4 x float> poison, <4 x i32> <i32 0, i32 0, i32 2, i32 3>
+; CHECK-NEXT:    [[TMP8:%.*]] = fadd <4 x float> [[TMP3]], [[TMP7]]
+; CHECK-NEXT:    ret <4 x float> [[TMP8]]
+;
+  %gep1 = getelementptr inbounds <4 x float>, ptr %x, i64 0, i64 1
+  %x0 = load float, ptr %x, align 4
+  %x1 = load float, ptr %gep1, align 4
+  %add1 = fadd float %a, %v
+  %add2 = fadd float %a, %v
+  %add3 = fadd float %a, %x0
+  %add4 = fadd float %a, %x1
+  %i0 = insertelement <4 x float> undef, float %add1, i32 0
+  %i1 = insertelement <4 x float> %i0, float %add2, i32 1
+  %i2 = insertelement <4 x float> %i1, float %add3, i32 2
+  %i3 = insertelement <4 x float> %i2, float %add4, i32 3
+  ret <4 x float> %i3
+}