[llvm] [llvm] Change `fp128` lowering to use `f128` functions by default (PR #76558)

[Ulrich Weigand via llvm-commits]

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@@ -39,7 +39,7 @@ define double @f5(double %x, double %y) {
 
 define fp128 @f6(fp128 %x, fp128 %y) {
 ; CHECK-LABEL: f6:
-; CHECK: brasl %r14, powl at PLT
+; CHECK: brasl %r14, powf128 at PLT
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uweigand wrote:

I'm a bit concerned about making this change by default, I don't see that this has any actual advantages on s390x (*l is always correct here anyway), and it might cause some surprises.  For example, while current glibc version do indeed provide the *f128 aliases, that has not always been the case - e.g. RHEL 7 doesn't have them.

https://github.com/llvm/llvm-project/pull/76558