[llvm] [LV][NFC] Use APFloat class when printing out costs per lane (PR #201824)

[Luke Lau via llvm-commits]

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@@ -9,16 +10,16 @@ target triple = "thumbv8.1m.main-unknown-none-eabihf"
 ; In this function the spills make it not profitable to vectorize if considering
 ; register pressure.
 define void @spills_not_profitable(ptr %in1, ptr %in2, ptr %out, i32 %n) {
-; CHECK-LABEL: LV: Checking a loop in 'spills_not_profitable'
-; CHECK: LV: Scalar loop costs: 86
-; CHECK-NOPRESSURE: Cost for VF 2: 394 (Estimated cost per lane: 197.
-; CHECK-NOPRESSURE: Cost for VF 4: 338 (Estimated cost per lane: 84.
-; CHECK-NOPRESSURE: LV: Selecting VF: 4
-; CHECK-PRESSURE: LV(REG): Cost of 50 from 25 spills of Generic::VectorRC
-; CHECK-PRESSURE-NEXT: Cost for VF 2: 444 (Estimated cost per lane: 222.
-; CHECK-PRESSURE: LV(REG): Cost of 50 from 25 spills of Generic::VectorRC
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lukel97 wrote:

Looks like the LV(REG) lines got dropped, do we need another `--filter` regex?

https://github.com/llvm/llvm-project/pull/201824