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

From-SVN: r4742

diff --git a/gcc/config/sparc/sparc.c b/gcc/config/sparc/sparc.c
index 5ecaa65ba7ee9637f0017367a583f2e295fe876d..361d33235315f6550b524572c532dffea2e83ba2 100644 (file)
--- a/gcc/config/sparc/sparc.c
+++ b/gcc/config/sparc/sparc.c
@@ -1156,8 +1156,19 @@ output_move_double (operands)
   else if (optype0 == REGOP && optype1 != REGOP
           && reg_overlap_mentioned_p (op0, op1))
     {
-      /* ??? This fails if the address is a double register address, each
-        of which is clobbered by operand 0.  */
+      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 ("add %1,%0,%1", xops);
+         operands[1] = gen_rtx (MEM, DImode, latehalf[0]);
+         latehalf[1] = adj_offsettable_operand (operands[1], 4);
+       }
       /* Do the late half first.  */
       output_asm_insn (singlemove_string (latehalf), latehalf);
       /* Then clobber.  */