tcg-arm: fix qemu_ld64

Emulating fldl on arm doesn't seem to work too well. It's the way
qemu_ld64 is translated to arm instructions.

        tcg_out_ld32_12(s, COND_AL, data_reg, addr_reg, 0);
        tcg_out_ld32_12(s, COND_AL, data_reg2, addr_reg, 4);

Consider case where data_reg==0, data_reg2==1, and addr_reg==0. First load
overwrited addr_reg. So let's put an if (data_ref==addr_reg).

(Pablo Virolainen)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6808 c046a42c-6fe2-441c-8c8c-71466251a162

tcg/arm/tcg-target.c

@@ -1011,8 +1011,13 @@ static inline void tcg_out_qemu_ld(TCGContext *s, int cond,
     case 3:
         /* TODO: use block load -
          * check that data_reg2 > data_reg or the other way */
-        tcg_out_ld32_12(s, COND_AL, data_reg, addr_reg, 0);
-        tcg_out_ld32_12(s, COND_AL, data_reg2, addr_reg, 4);
+        if (data_reg == addr_reg) {
+            tcg_out_ld32_12(s, COND_AL, data_reg2, addr_reg, 4);
+            tcg_out_ld32_12(s, COND_AL, data_reg, addr_reg, 0);
+        } else {
+            tcg_out_ld32_12(s, COND_AL, data_reg, addr_reg, 0);
+            tcg_out_ld32_12(s, COND_AL, data_reg2, addr_reg, 4);
+        }
         break;
     }
 #endif