[Bug c/93819] PPC64 builtin vec_rlnm() argument order is wrong.

[cel at us dot ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93819

--- Comment #1 from Carl Love <cel at us dot ibm.com> ---
Created attachment 47873
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47873&action=edit
Patch to fix vec_vrlnm() functionality

The issue with the vec_rlnm() builtin is the order of the arguments in the
builtin macro definition in gcc/config/rs6000/altivec.h.  I have attached a
patch to fix the issue.  Here is the fix as well

--- a/gcc/config/rs6000/altivec.h
+++ b/gcc/config/rs6000/altivec.h
@@ -182,7 +182,7 @@
 #define vec_recipdiv __builtin_vec_recipdiv
 #define vec_rlmi __builtin_vec_rlmi
 #define vec_vrlnm __builtin_vec_rlnm
-#define vec_rlnm(a,b,c) (__builtin_vec_rlnm((a),((b)<<8)|(c)))
+#define vec_rlnm(a,b,c) (__builtin_vec_rlnm((a),((c)<<8)|(b)))
 #define vec_rsqrt __builtin_vec_rsqrt
 #define vec_rsqrte __builtin_vec_rsqrte
 #define vec_signed __builtin_vec_vsigned

Basically the second and third arguments to the macro need to be reversed.