[llvm] [CostModel][AArch64] Make extractelement, with fmul user, free whenev… (PR #111479)
David Sherwood via llvm-commits
llvm-commits at lists.llvm.org
Tue Oct 8 01:24:06 PDT 2024
================
----------------
david-arm wrote:
Do we also need a test when there are multiple uses of extractelement, i.e. something like
```
define double @extract_multiple_use(<2 x double> %a) {
entry:
%1 = extractelement <2 x double> %a, i32 0
%2 = extractelement <2 x double> %a, i32 1
%res1 = fmul double %1, %2
%res2 = fadd double %1, %2
%res3 = fadd double %res1, %res2
ret double %res3
}
```
In this case it's not immediately obvious that we will end up with the efficient form of fmul so I'm hoping the cost model deals with multiple use cases correctly.
https://github.com/llvm/llvm-project/pull/111479
More information about the llvm-commits
mailing list