function.c (diddle_return_value): Examine current_function_return_rtx instead of...

        * function.c (diddle_return_value): Examine
        current_function_return_rtx instead of the DECL_RESULT.
        (expand_function_end): Handle reloading DECL_RESULT from memory
        into a hard register.  Query promote_mode for sign of mismatched
        modes.

From-SVN: r36769

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8d3af12dfe776f73d9f13a7e806b560b834a5951..4c6d27590cde937b6d464204943c21a54914fe8a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2000-10-06  Richard Henderson  <rth@cygnus.com>
+
+       * function.c (diddle_return_value): Examine
+       current_function_return_rtx instead of the DECL_RESULT.
+       (expand_function_end): Handle reloading DECL_RESULT from memory
+       into a hard register.  Query promote_mode for sign of mismatched
+       modes.
+
 2000-10-06  Vladimir Makarov  <vmakarov@touchme.toronto.redhat.com>
 
        * haifa-sched.c (schedule_insns): Fix typo in freeing

diff --git a/gcc/function.c b/gcc/function.c
index 85a18bf0b8739937fca265ee2d0962f3a464593a..11ceea7c971fa32c6cd4698d1d911a3d0793afd5 100644 (file)
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -6444,8 +6444,7 @@ diddle_return_value (doit, arg)
       /* If this is a BLKmode structure being returned in registers, then use
         the mode computed in expand_return.  */
       if (GET_MODE (outgoing) == BLKmode)
-       PUT_MODE (outgoing,
-                 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
+       PUT_MODE (outgoing, GET_MODE (current_function_return_rtx));
       REG_FUNCTION_VALUE_P (outgoing) = 1;
     }
 
@@ -6730,37 +6729,58 @@ expand_function_end (filename, line, end_bindings)
        emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
       }
 
-  /* If scalar return value was computed in a pseudo-reg,
-     copy that to the hard return register.  */
-  if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0
-      && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG
-      && (REGNO (DECL_RTL (DECL_RESULT (current_function_decl)))
-         >= FIRST_PSEUDO_REGISTER))
+  /* If scalar return value was computed in a pseudo-reg, or was a named
+     return value that got dumped to the stack, copy that to the hard
+     return register.  */
+  if (DECL_RTL (DECL_RESULT (current_function_decl)) != 0)
     {
-      rtx real_decl_result;
+      tree decl_result = DECL_RESULT (current_function_decl);
+      rtx decl_rtl = DECL_RTL (decl_result);
+
+      if (REG_P (decl_rtl)
+         ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
+         : DECL_REGISTER (decl_result))
+       {
+         rtx real_decl_rtl;
 
 #ifdef FUNCTION_OUTGOING_VALUE
-      real_decl_result
-       = FUNCTION_OUTGOING_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
-                                  current_function_decl);
+         real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
+                                                  current_function_decl);
 #else
-      real_decl_result
-       = FUNCTION_VALUE (TREE_TYPE (DECL_RESULT (current_function_decl)),
-                         current_function_decl);
+         real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
+                                         current_function_decl);
 #endif
-      REG_FUNCTION_VALUE_P (real_decl_result) = 1;
-      /* If this is a BLKmode structure being returned in registers, then use
-        the mode computed in expand_return.  */
-      if (GET_MODE (real_decl_result) == BLKmode)
-       PUT_MODE (real_decl_result,
-                 GET_MODE (DECL_RTL (DECL_RESULT (current_function_decl))));
-      emit_move_insn (real_decl_result,
-                     DECL_RTL (DECL_RESULT (current_function_decl)));
-
-      /* The delay slot scheduler assumes that current_function_return_rtx
-        holds the hard register containing the return value, not a temporary
-        pseudo.  */
-      current_function_return_rtx = real_decl_result;
+         REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
+
+         /* If this is a BLKmode structure being returned in registers,
+            then use the mode computed in expand_return.  Note that if
+            decl_rtl is memory, then its mode may have been changed, 
+            but that current_function_return_rtx has not.  */
+         if (GET_MODE (real_decl_rtl) == BLKmode)
+           PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
+
+         /* If a named return value dumped decl_return to memory, then
+            we may need to re-do the PROMOTE_MODE signed/unsigned 
+            extension.  */
+         if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
+           {
+             int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
+
+#ifdef PROMOTE_FUNCTION_RETURN
+             promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
+                           &unsignedp, 1);
+#endif
+
+             convert_move (real_decl_rtl, decl_rtl, unsignedp);
+           }
+         else
+           emit_move_insn (real_decl_rtl, decl_rtl);
+
+         /* The delay slot scheduler assumes that current_function_return_rtx
+            holds the hard register containing the return value, not a
+            temporary pseudo.  */
+         current_function_return_rtx = real_decl_rtl;
+       }
     }
 
   /* If returning a structure, arrange to return the address of the value