[llvm] [TTI][AArch64] Detect OperandInfo from scalable splats. (PR #122469)

[David Green via llvm-commits]

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@@ -339,24 +339,24 @@ define void @sdiv_uniformconstpow2() {
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 99 for instruction: %V16i8 = sdiv <16 x i8> undef, splat (i8 16)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 198 for instruction: %V32i8 = sdiv <32 x i8> undef, splat (i8 16)
 ; CHECK-NEXT:  Cost Model: Found an estimated cost of 396 for instruction: %V64i8 = sdiv <64 x i8> undef, splat (i8 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV2i64 = sdiv <vscale x 2 x i64> undef, splat (i64 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %NV4i64 = sdiv <vscale x 4 x i64> undef, splat (i64 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %NV8i64 = sdiv <vscale x 8 x i64> undef, splat (i64 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV2i32 = sdiv <vscale x 2 x i32> undef, splat (i32 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV4i32 = sdiv <vscale x 4 x i32> undef, splat (i32 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 4 for instruction: %NV8i32 = sdiv <vscale x 8 x i32> undef, splat (i32 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %NV16i32 = sdiv <vscale x 16 x i32> undef, splat (i32 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV2i16 = sdiv <vscale x 2 x i16> undef, splat (i16 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV4i16 = sdiv <vscale x 4 x i16> undef, splat (i16 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %NV8i16 = sdiv <vscale x 8 x i16> undef, splat (i16 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 16 for instruction: %NV16i16 = sdiv <vscale x 16 x i16> undef, splat (i16 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 32 for instruction: %NV32i16 = sdiv <vscale x 32 x i16> undef, splat (i16 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV2i8 = sdiv <vscale x 2 x i8> undef, splat (i8 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 2 for instruction: %NV4i8 = sdiv <vscale x 4 x i8> undef, splat (i8 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 8 for instruction: %NV8i8 = sdiv <vscale x 8 x i8> undef, splat (i8 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 16 for instruction: %NV16i8 = sdiv <vscale x 16 x i8> undef, splat (i8 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 32 for instruction: %NV32i8 = sdiv <vscale x 32 x i8> undef, splat (i8 16)
-; CHECK-NEXT:  Cost Model: Found an estimated cost of 64 for instruction: %NV64i8 = sdiv <vscale x 64 x i8> undef, splat (i8 16)
+; CHECK-NEXT:  Cost Model: Found an estimated cost of 5 for instruction: %NV2i64 = sdiv <vscale x 2 x i64> undef, splat (i64 16)
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davemgreen wrote:

Yep for the moment, due to the opt-opt in llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp. They should change again in a future patch, but that should happen in a more reliable way where it applies to all vector types.

https://github.com/llvm/llvm-project/pull/122469