[llvm] [SLP]Add support for strided loads. (PR #80310)

[Alexey Bataev via llvm-commits]

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@@ -30,7 +30,7 @@ define void @test() {
 ; CHECK-SLP-THRESHOLD:       bb:
 ; CHECK-SLP-THRESHOLD-NEXT:    [[TMP0:%.*]] = insertelement <4 x ptr> poison, ptr [[COND_IN_V]], i32 0
 ; CHECK-SLP-THRESHOLD-NEXT:    [[TMP1:%.*]] = shufflevector <4 x ptr> [[TMP0]], <4 x ptr> poison, <4 x i32> zeroinitializer
-; CHECK-SLP-THRESHOLD-NEXT:    [[TMP2:%.*]] = getelementptr i64, <4 x ptr> [[TMP1]], <4 x i64> <i64 0, i64 4, i64 8, i64 12>
+; CHECK-SLP-THRESHOLD-NEXT:    [[TMP2:%.*]] = getelementptr i64, <4 x ptr> [[TMP1]], <4 x i64> <i64 12, i64 8, i64 4, i64 0>
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alexey-bataev wrote:

Same reason, as above. Before these patch we did not check, if it is important for the target to treat strided loads as strided or better to continue treating them as masked gathers. Since X86 currently does not support strided loads, the reordering does not kick in and causes these changes.

https://github.com/llvm/llvm-project/pull/80310