[Bug middle-end/110711] possible missed optimization for std::max with -march=znver2

[crazylht at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110711

--- Comment #7 from Hongtao.liu <crazylht at gmail dot com> ---
git diff gcc12_171t.ifcvt gcc13.173.ifcvt

   <bb 5> [local count: 955630227]:
-  # i_22 = PHI <i_16(10), 1(19)>
+  # i_21 = PHI <i_16(10), 1(19)>
   # prephitmp_19 = PHI <prephitmp_24(10), _1(19)>
-  _2 = i_22 * 8;
+  _2 = i_21 * 8;
   _3 = a_10(D) + _2;
   _17 = MEM[(const double &)_3];
-  prephitmp_24 = MAX_EXPR <_17, prephitmp_19>;
-  i_16 = i_22 + 1;
+  _29 = MAX_EXPR <_17, prephitmp_19>;
+  prephitmp_24 = _29;
+  i_16 = i_21 + 1;
   if (n_els_7(D) > i_16)
     goto <bb 10>; [89.00%]
   else
     goto <bb 13>; [11.00%]

   <bb 13> [local count: 105119324]:
-  # prephitmp_13 = PHI <prephitmp_24(5), prephitmp_12(16)>
+  # prephitmp_15 = PHI <_29(5), prephitmp_27(16)>
   goto <bb 8>; [100.00%]