tcg-ppc64: Fix add2_i64

add2_i64 was adding the lower double word to the upper double word
of each input. Fix this so we add the lower double words, then the
upper double words with carry propagation.

Cc: qemu-stable@nongnu.org
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NRichard Henderson <rth@twiddle.net>

tcg/ppc64/tcg-target.c

@@ -1959,18 +1959,18 @@ static void tcg_out_op (TCGContext *s, TCGOpcode opc, const TCGArg *args,
            environment.  So in 64-bit mode it's always carry-out of bit 63.
            The fallback code using deposit works just as well for 32-bit.  */
         a0 = args[0], a1 = args[1];
-        if (a0 == args[4] || (!const_args[5] && a0 == args[5])) {
+        if (a0 == args[3] || (!const_args[5] && a0 == args[5])) {
             a0 = TCG_REG_R0;
         }
-        if (const_args[3]) {
-            tcg_out32(s, ADDIC | TAI(a0, args[2], args[3]));
+        if (const_args[4]) {
+            tcg_out32(s, ADDIC | TAI(a0, args[2], args[4]));
         } else {
-            tcg_out32(s, ADDC | TAB(a0, args[2], args[3]));
+            tcg_out32(s, ADDC | TAB(a0, args[2], args[4]));
         }
         if (const_args[5]) {
-            tcg_out32(s, (args[5] ? ADDME : ADDZE) | RT(a1) | RA(args[4]));
+            tcg_out32(s, (args[5] ? ADDME : ADDZE) | RT(a1) | RA(args[3]));
         } else {
-            tcg_out32(s, ADDE | TAB(a1, args[4], args[5]));
+            tcg_out32(s, ADDE | TAB(a1, args[3], args[5]));
         }
         if (a0 != args[0]) {
             tcg_out_mov(s, TCG_TYPE_I64, args[0], a0);
@@ -2148,7 +2148,7 @@ static const TCGTargetOpDef ppc_op_defs[] = {
     { INDEX_op_deposit_i32, { "r", "0", "rZ" } },
     { INDEX_op_deposit_i64, { "r", "0", "rZ" } },
 
-    { INDEX_op_add2_i64, { "r", "r", "r", "rI", "r", "rZM" } },
+    { INDEX_op_add2_i64, { "r", "r", "r", "r", "rI", "rZM" } },
     { INDEX_op_sub2_i64, { "r", "r", "rI", "r", "rZM", "r" } },
     { INDEX_op_muls2_i64, { "r", "r", "r", "r" } },
     { INDEX_op_mulu2_i64, { "r", "r", "r", "r" } },