[PATCH, rs6000] Disable gimple fold for float or double vec_minmax when fast-math is not set

[David Edelsohn]

2021-08-25 Haochen Gui <guihaoc@linux.ibm.com>

gcc/
     * config/rs6000/rs6000-call.c (rs6000_gimple_fold_builtin):
     Modify the VSX_BUILTIN_XVMINDP, ALTIVEC_BUILTIN_VMINFP,
     VSX_BUILTIN_XVMAXDP, ALTIVEC_BUILTIN_VMAXFP expansions.

Please write something more than "modify".  The ChangeLog should be
more like the email subject line for this patch.

gcc/testsuite/
     * gcc.target/powerpc/vec-minmax-1.c: New test.
     * gcc.target/powerpc/vec-minmax-2.c: Likewise.

Please ensure that the indentation is correct for the case statements;
it was unclear from the text pasted into the email.

Okay with those clarifications.

Thanks, David