Comment 3 for bug 2011832

For https://gitlab.com/qemu-project/qemu/-/issues/1547 the case is well testable and visible.
If you couldn't spit it, min/max goes nuts in those tests, like:
 farr[11] = 4.318749e+04, farr[3] = 1.468766e+00
-C MIN(farr[11],farr[3]) = 1.468766e+00, MAX(farr[11],farr[3]) = 4.318749e+04
+C MIN(farr[11],farr[3]) = 4.318749e+04, MAX(farr[11],farr[3]) = 4.318749e+04

While executing code like this:
 #define RT_MIN(a, b) ((a) < (b) ? (a) : (b))
 #define RT_MAX(a, b) ((a) > (b) ? (a) : (b))

Optimization makes it use some feature which is broken in emulation.

I see the issue happening with -O1 and higher on the case that was described.
Looking at the assembly I see that the bad code used xsmincdp and xsmaxcdp.

The fix that should be in:
  201fc774e0e target/ppc: Fix xs{max, min}[cj]dp to use VSX registers

I have again asked on the upstream case if anyone knows better.
Rechecking there in a few days would be great.