[Bug target/103515] Unexpected OPTION_MASK_SAVE_TOC_INDIRECT of rs6000_isa_flag

["linkw at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103515

--- Comment #2 from Kewen Lin <linkw at gcc dot gnu.org> ---
Here I assumed that the current cl optimization/option save and restore scheme
wants to keep the global_option/global_option_set same as the one from the
initial option processing.  After we parsing all attributes/pragmas, we can
expect the rs6000_isa_flags back to the default one.

The fix seems to require us to take this OPTION_MASK_SAVE_TOC_INDIRECT as one
option which would be affected by optimize level.

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 327822e5357..f9ee7044889 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -3478,6 +3478,16 @@ rs6000_override_options_after_change (void)
     }
   else if (!OPTION_SET_P (flag_cunroll_grow_size))
     flag_cunroll_grow_size = flag_peel_loops || optimize >= 3;
+  /* If we can shrink-wrap the TOC register save separately, then use
+     -msave-toc-indirect unless explicitly disabled.  */
+  if ((rs6000_isa_flags_explicit & OPTION_MASK_SAVE_TOC_INDIRECT) == 0
+      && flag_shrink_wrap_separate
+      && optimize_function_for_speed_p (cfun))
+    rs6000_isa_flags |= OPTION_MASK_SAVE_TOC_INDIRECT;
+  else
+    rs6000_isa_flags &= ~OPTION_MASK_SAVE_TOC_INDIRECT;


Also require us to build one target_node when we are going to save one new
optimization_node which isn't the same as the default one, since at that time
the optimization level changes and the option is possible to be changed as
well.

diff --git a/gcc/attribs.c b/gcc/attribs.c
index c252f5af07b..3382c095fa8 100644
--- a/gcc/attribs.c
+++ b/gcc/attribs.c
@@ -607,7 +607,14 @@ decl_attributes (tree *node, tree attributes, int flags,
   if (TREE_CODE (*node) == FUNCTION_DECL
       && optimization_current_node != optimization_default_node
       && !DECL_FUNCTION_SPECIFIC_OPTIMIZATION (*node))
-    DECL_FUNCTION_SPECIFIC_OPTIMIZATION (*node) = optimization_current_node;
+    {
+      DECL_FUNCTION_SPECIFIC_OPTIMIZATION (*node) = optimization_current_node;
+      tree target_node
+        = build_target_option_node (&global_options, &global_options_set);
+      if (!DECL_FUNCTION_SPECIFIC_TARGET (*node)
+          && target_node != target_option_default_node)
+        DECL_FUNCTION_SPECIFIC_TARGET (*node) = target_node;
+    }

   /* If this is a function and the user used #pragma GCC target, add the
      options to the attribute((target(...))) list.  */