[PATCH] D148174: [SLP]Introduce gather cost estimation function.

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


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Comment at: llvm/test/Transforms/SLPVectorizer/AArch64/extractelements-to-shuffle.ll:6
 ; CHECK-LABEL: @test(
-; CHECK-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP1:%.*]], i64 0
-; CHECK-NEXT:    [[TMP5:%.*]] = or i64 [[TMP4]], 0
-; CHECK-NEXT:    [[TMP6:%.*]] = trunc i64 [[TMP5]] to i32
-; CHECK-NEXT:    [[TMP7:%.*]] = extractelement <2 x i64> [[TMP0:%.*]], i64 0
-; CHECK-NEXT:    [[TMP8:%.*]] = or i64 [[TMP7]], 0
-; CHECK-NEXT:    [[TMP9:%.*]] = trunc i64 [[TMP8]] to i32
-; CHECK-NEXT:    [[TMP10:%.*]] = extractelement <2 x i64> [[TMP2:%.*]], i64 0
-; CHECK-NEXT:    [[TMP11:%.*]] = extractelement <2 x i64> [[TMP2]], i64 1
-; CHECK-NEXT:    [[TMP12:%.*]] = or i64 [[TMP10]], [[TMP11]]
-; CHECK-NEXT:    [[TMP13:%.*]] = trunc i64 [[TMP12]] to i32
-; CHECK-NEXT:    [[TMP14:%.*]] = extractelement <2 x i64> [[TMP0]], i64 0
-; CHECK-NEXT:    [[TMP15:%.*]] = or i64 [[TMP14]], 0
-; CHECK-NEXT:    [[TMP16:%.*]] = trunc i64 [[TMP15]] to i32
-; CHECK-NEXT:    br label [[TMP17:%.*]]
-; CHECK:       17:
-; CHECK-NEXT:    [[TMP18:%.*]] = phi i32 [ [[TMP22:%.*]], [[TMP17]] ], [ [[TMP6]], [[TMP3:%.*]] ]
-; CHECK-NEXT:    [[TMP19:%.*]] = phi i32 [ 0, [[TMP17]] ], [ [[TMP9]], [[TMP3]] ]
-; CHECK-NEXT:    [[TMP20:%.*]] = phi i32 [ 0, [[TMP17]] ], [ [[TMP13]], [[TMP3]] ]
-; CHECK-NEXT:    [[TMP21:%.*]] = phi i32 [ 0, [[TMP17]] ], [ [[TMP16]], [[TMP3]] ]
-; CHECK-NEXT:    [[TMP22]] = or i32 [[TMP18]], 0
-; CHECK-NEXT:    br label [[TMP17]]
+; CHECK-NEXT:    [[TMP4:%.*]] = extractelement <2 x i64> [[TMP2:%.*]], i64 0
+; CHECK-NEXT:    [[TMP5:%.*]] = shufflevector <2 x i64> [[TMP1:%.*]], <2 x i64> [[TMP0:%.*]], <4 x i32> <i32 0, i32 2, i32 undef, i32 2>
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ABataev wrote:
> ABataev wrote:
> > dmgreen wrote:
> > > I think this is hitting issues we've already seen: https://reviews.llvm.org/rGcbcdd747e85b8d33b821d94d8114b971f31fd0d2.
> > > From https://reviews.llvm.org/D141940#4141069
> > Looks like the issue with buildvector cost estimation, will fix it.
> I mean getGatherCost function.
There is another one problem. When estimating the cost of the insertelement instruction, the TTI for AArch64 return 0, because it tries to insert to 0 position and HasRealUse is false 


Repository:
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  https://reviews.llvm.org/D148174/new/

https://reviews.llvm.org/D148174