i386.c (output_fix_trunc): Add code to emulate non-popping DImode case.

        * i386.c (output_fix_trunc): Add code to emulate non-popping DImode
        case.

From-SVN: r19538

gcc/ChangeLog

+Tue May  5 01:43:16 1998  Jim Wilson  <wilson@cygnus.com>
+
+	* i386.c (output_fix_trunc): Add code to emulate non-popping DImode
+	case.
+
 Tue May  5 01:15:06 1998  Jeffrey A Law  (law@cygnus.com)
 
 	* reorg.c (fill_slots_from_thread): Update REG_DEAD/REG_UNUSED notes

gcc/config/i386/i386.c

@@ -3943,8 +3943,7 @@ output_fix_trunc (insn, operands)
   int stack_top_dies = find_regno_note (insn, REG_DEAD, FIRST_STACK_REG) != 0;
   rtx xops[2];
 
-  if (! STACK_TOP_P (operands[1])
-      || (GET_MODE (operands[0]) == DImode && ! stack_top_dies))
+  if (! STACK_TOP_P (operands[1]))
     abort ();
 
   xops[0] = GEN_INT (12);
@@ -3963,6 +3962,17 @@ output_fix_trunc (insn, operands)
     {
       if (stack_top_dies)
 	output_asm_insn (AS1 (fistp%z0,%0), operands);
+      else if (GET_MODE (operands[0]) == DImode && ! stack_top_dies)
+	{
+	  /* There is no DImode version of this without a stack pop, so
+	     we must emulate it.  It doesn't matter much what the second
+	     instruction is, because the value being pushed on the FP stack
+	     is not used except for the following stack popping store.
+	     This case can only happen without optimization, so it doesn't
+	     matter that it is inefficient.  */
+	  output_asm_insn (AS1 (fistp%z0,%0), operands);
+	  output_asm_insn (AS1 (fild%z0,%0), operands);
+	}
       else
 	output_asm_insn (AS1 (fist%z0,%0), operands);
     }