calls.c (expand_call): If TARGET is passed by reference and is readonly, write a...

	* calls.c (expand_call): If TARGET is passed by reference and
	is readonly, write a CLOBBER.

From-SVN: r32716

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index baf3ad6..45bfc37 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+Thu Mar 23 17:10:48 2000  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
+
+       * calls.c (expand_call): If TARGET is passed by reference and
+       is readonly, write a CLOBBER.
+
 2000-03-23  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
        * builtins.c (expand_builtin): Handle bcmp.

diff --git a/gcc/calls.c b/gcc/calls.c
index 4c8d573..dfb38ee 100644 (file)
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -2776,6 +2776,14 @@ expand_call (exp, target, ignore)
       if (is_longjmp)
        current_function_calls_longjmp = 1, sibcall_failure = 1;
 
+      /* If this function is returning into a memory location marked as
+        readonly, it means it is initializing that location.  But we normally
+        treat functions as not clobbering such locations, so we need to
+        specify that this one does.  */
+      if (target != 0 && GET_CODE (target) == MEM
+         && structure_value_addr != 0 && RTX_UNCHANGING_P (target))
+       emit_insn (gen_rtx_CLOBBER (VOIDmode, target));
+
       /* If value type not void, return an rtx for the value.  */
 
       /* If there are cleanups to be called, don't use a hard reg as target.