[PATCH] D76956: [TTI][SLP] Add TTI interface to estimate cost of chain of vector inserts/extracts.

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/resched.ll:22-29
+; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <8 x i32> undef, i32 [[CONV31_I]], i32 0
+; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x i32> [[TMP1]], i32 [[CONV31_I]], i32 1
+; CHECK-NEXT:    [[TMP3:%.*]] = insertelement <8 x i32> [[TMP2]], i32 [[CONV31_I]], i32 2
+; CHECK-NEXT:    [[TMP4:%.*]] = insertelement <8 x i32> [[TMP3]], i32 [[CONV31_I]], i32 3
+; CHECK-NEXT:    [[TMP5:%.*]] = insertelement <8 x i32> [[TMP4]], i32 [[CONV31_I]], i32 4
+; CHECK-NEXT:    [[TMP6:%.*]] = insertelement <8 x i32> [[TMP5]], i32 [[CONV31_I]], i32 5
+; CHECK-NEXT:    [[TMP7:%.*]] = insertelement <8 x i32> [[TMP6]], i32 [[CONV31_I]], i32 6
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Did SLP fail to recognize that this is a splat shuffle? I would have expected it to produce splat IR:
(shuffle (insert X, 0), zeroinitializer)
...instead of a chain of inserts.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D76956/new/

https://reviews.llvm.org/D76956