gcc/

	* calls.c (avoid_likely_spilled_reg): New function.
	(expand_call): Use it.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@127360 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d949292..906930e 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2007-08-11  Richard Sandiford  <richard@codesourcery.com>
+
+       * calls.c (avoid_likely_spilled_reg): New function.
+       (expand_call): Use it.
+
 2007-08-11  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
        * c-typeck.c (build_c_cast): Add OPT_Wcast_qual to warnings.

diff --git a/gcc/calls.c b/gcc/calls.c
index 98fc8f5..df9ef39 100644 (file)
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -1856,6 +1856,31 @@ shift_return_value (enum machine_mode mode, bool left_p, rtx value)
   return true;
 }
 
+/* If X is a likely-spilled register value, copy it to a pseudo
+   register and return that register.  Return X otherwise.  */
+
+static rtx
+avoid_likely_spilled_reg (rtx x)
+{
+  rtx new;
+
+  if (REG_P (x)
+      && HARD_REGISTER_P (x)
+      && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (x))))
+    {
+      /* Make sure that we generate a REG rather than a CONCAT.
+        Moves into CONCATs can need nontrivial instructions,
+        and the whole point of this function is to avoid
+        using the hard register directly in such a situation.  */
+      generating_concat_p = 0;
+      new = gen_reg_rtx (GET_MODE (x));
+      generating_concat_p = 1;
+      emit_move_insn (new, x);
+      return new;
+    }
+  return x;
+}
+
 /* Generate all the code for a CALL_EXPR exp
    and return an rtx for its value.
    Store the value in TARGET (specified as an rtx) if convenient.
@@ -2953,11 +2978,8 @@ expand_call (tree exp, rtx target, int ignore)
 
          /* We have to copy a return value in a CLASS_LIKELY_SPILLED hard
             reg to a plain register.  */
-         if (REG_P (valreg)
-             && HARD_REGISTER_P (valreg)
-             && CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (REGNO (valreg)))
-             && !(REG_P (target) && !HARD_REGISTER_P (target)))
-           valreg = copy_to_reg (valreg);
+         if (!REG_P (target) || HARD_REGISTER_P (target))
+           valreg = avoid_likely_spilled_reg (valreg);
 
          /* If TARGET is a MEM in the argument area, and we have
             saved part of the argument area, then we can't store
@@ -3002,7 +3024,7 @@ expand_call (tree exp, rtx target, int ignore)
          sibcall_failure = 1;
        }
       else
-       target = copy_to_reg (valreg);
+       target = copy_to_reg (avoid_likely_spilled_reg (valreg));
 
       if (targetm.calls.promote_function_return(funtype))
        {