re PR middle-end/46297 (gfortran.dg/g77/980701-0.f FAILs with -Os -fno-asynchronous-unwind-tables)

	PR middle-end-optimization/46297
	* postreload.c (reload_combine_note_store): Deal with embedded
	side effects in MEM expressions.

	* gfortran.dg/pr46297.f: New test.

From-SVN: r166905

gcc/ChangeLog

+2010-11-18  Jeff Law  <law@redhat.com>
+
+	PR middle-end-optimization/46297
+	* postreload.c (reload_combine_note_store): Deal with embedded
+	side effects in MEM expressions.
+
 2010-11-18  Richard Guenther  <rguenther@suse.de>
 
 	PR lto/45089

gcc/postreload.c

@@ -1409,6 +1409,31 @@ reload_combine_note_store (rtx dst, const_rtx set, void *data ATTRIBUTE_UNUSED)
 				   GET_MODE (dst));
       dst = SUBREG_REG (dst);
     }
+
+  /* Some targets do argument pushes without adding REG_INC notes.  */
+
+  if (MEM_P (dst))
+    {
+      dst = XEXP (dst, 0);
+      if (GET_CODE (dst) == PRE_INC || GET_CODE (dst) == POST_INC
+	  || GET_CODE (dst) == PRE_DEC || GET_CODE (dst) == POST_DEC)
+	{
+	  regno = REGNO (XEXP (dst, 0));
+	  mode = GET_MODE (XEXP (dst, 0));
+	  for (i = hard_regno_nregs[regno][mode] - 1 + regno; i >= regno; i--)
+	    {
+	      /* We could probably do better, but for now mark the register
+		 as used in an unknown fashion and set/clobbered at this
+		 insn.  */
+	      reg_state[i].use_index = -1;
+	      reg_state[i].store_ruid = reload_combine_ruid;
+	      reg_state[i].real_store_ruid = reload_combine_ruid;
+	    }
+	}
+      else
+        return;
+    }
+
   if (!REG_P (dst))
     return;
   regno += REGNO (dst);

gcc/testsuite/ChangeLog

+2010-11-18  Jeff Law  <law@redhat.com>
+
+	PR middle-end-optimization/46297
+	* gfortran.dg/pr46297.f: New test.
+
 2010-11-17  Steve Ellcey  <sje@cup.hp.com>
 
 	PR middle-end/31490

gcc/testsuite/gfortran.dg/pr46297.f

+! { dg-options "-Os -fno-asynchronous-unwind-tables" }
+! { dg-do run }
+
+      real r1(5), r2(5), r3(5)
+      real s1(2), s2(2), s3(2)
+      double precision d1, d2, d3
+      equivalence (r3, s3(2))
+      equivalence (d3, r3(2))
+      s1(1) = 1.
+      s3(1) = 3.
+      r3(1) = 3.
+      d3 = 30.
+      i3 = 3
+      call x (s1, r1, d1, i1, s2, r2, d2, i2, s3, r3, d3, i3)
+      end
+      subroutine x (s1, r1, d1, i1, s2, r2, d2, i2, s3, r3, d3, i3)
+      real r1(5), r2(5), r3(5)
+      real s1(2), s2(2), s3(2)
+      double precision d1, d2, d3
+      if (s1(1) .ne. 1.) call abort
+      if (s3(1) .ne. 3.) call abort
+      if (r3(1) .ne. 3.) call abort
+      if (d3 .ne. 30.) call abort
+      if (i3 .ne. 3) call abort
+      end