(output_move_double): Handle reg[n,n+1] = mem[reg[n] + reg[n+1]].

From-SVN: r4789

1 files changed, 36 insertions, 1 deletions

diff --git a/gcc/config/ns32k/ns32k.c b/gcc/config/ns32k/ns32k.c
index eb47d9c..6dd4a96 100644
--- a/gcc/config/ns32k/ns32k.c
+++ b/gcc/config/ns32k/ns32k.c
@@ -316,7 +316,42 @@ output_move_double (operands)
       return singlemove_string (operands);
     }
 
-  /* Not autodecrementing.  Do the two words, low-numbered first.  */
+  /* If the first move would clobber the source of the second one,
+     do them in the other order.  */
+
+  /* Overlapping registers.  */
+  if (optype0 == REGOP && optype1 == REGOP
+      && REGNO (op0) == REGNO (latehalf[1]))
+    {
+      /* Do that word.  */
+      output_asm_insn (singlemove_string (latehalf), latehalf);
+      /* Do low-numbered word.  */
+      return singlemove_string (operands);
+    }
+  /* Loading into a register which overlaps a register used in the address.  */
+  else if (optype0 == REGOP && optype1 != REGOP
+	   && reg_overlap_mentioned_p (op0, op1))
+    {
+      if (reg_mentioned_p (op0, XEXP (op1, 0))
+	  && reg_mentioned_p (latehalf[0], XEXP (op1, 0)))
+	{
+	  /* If both halves of dest are used in the src memory address,
+	     add the two regs and put them in the low reg (op0).
+	     Then it works to load latehalf first.  */
+	  rtx xops[2];
+	  xops[0] = latehalf[0];
+	  xops[1] = op0;
+	  output_asm_insn ("addd %0,%1", xops);
+	  operands[1] = gen_rtx (MEM, DImode, op0);
+	  latehalf[1] = adj_offsettable_operand (operands[1], 4);
+	}
+      /* Do the late half first.  */
+      output_asm_insn (singlemove_string (latehalf), latehalf);
+      /* Then clobber.  */
+      return singlemove_string (operands);
+    }
+
+  /* Normal case.  Do the two words, low-numbered first.  */
 
   output_asm_insn (singlemove_string (operands), operands);