Fix register count when not splitting Complex IEEE 128-bit args.

    For ABI_V4, we do not split complex args. This created a problem because
    even though an arg would be passed in two VSX regs, we were only advancing the
    function arg counter by one VSX register. Fixed with this patch.

    (backported commit 2ee68beee709e48fce85b8892ff9985acc6a91a8)

gcc/
	PR target/99685
	* config/rs6000/rs6000-call.c (rs6000_function_arg_advance_1): Bump
	register count when not splitting IEEE 128-bit Complex.

diff --git a/gcc/config/rs6000/rs6000-call.c b/gcc/config/rs6000/rs6000-call.c
index c910ee5c71a662faf278e527d823a3d4bb2763b3..4e55cbaab55f45191f309a4661a48eb0e3b03f3b 100644 (file)
--- a/gcc/config/rs6000/rs6000-call.c
+++ b/gcc/config/rs6000/rs6000-call.c
@@ -6534,6 +6534,12 @@ rs6000_function_arg_advance_1 (CUMULATIVE_ARGS *cum, machine_mode mode,
        {
          cum->vregno += n_elts;
 
+         /* If we are not splitting Complex IEEE128 args then account for the
+            fact that they are passed in 2 VSX regs. */
+         if (!targetm.calls.split_complex_arg && type
+             && TREE_CODE (type) == COMPLEX_TYPE && elt_mode == KCmode)
+           cum->vregno++;
+
          if (!TARGET_ALTIVEC)
            error ("cannot pass argument in vector register because"
                   " altivec instructions are disabled, use %qs"