target/ppc: add ov32 flag for multiply low insns

For Multiply Word:
SO, OV, and OV32 bits reflects overflow of the 32-bit result

For Multiply DoubleWord:
SO, OV, and OV32 bits reflects overflow of the 64-bit result
Signed-off-by: NNikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

target/ppc/translate.c

@@ -1285,6 +1285,9 @@ static void gen_mullwo(DisasContext *ctx)
     tcg_gen_sari_i32(t0, t0, 31);
     tcg_gen_setcond_i32(TCG_COND_NE, t0, t0, t1);
     tcg_gen_extu_i32_tl(cpu_ov, t0);
+    if (is_isa300(ctx)) {
+        tcg_gen_mov_tl(cpu_ov32, cpu_ov);
+    }
     tcg_gen_or_tl(cpu_so, cpu_so, cpu_ov);
 
     tcg_temp_free_i32(t0);
@@ -1346,6 +1349,9 @@ static void gen_mulldo(DisasContext *ctx)
 
     tcg_gen_sari_i64(t0, t0, 63);
     tcg_gen_setcond_i64(TCG_COND_NE, cpu_ov, t0, t1);
+    if (is_isa300(ctx)) {
+        tcg_gen_mov_tl(cpu_ov32, cpu_ov);
+    }
     tcg_gen_or_tl(cpu_so, cpu_so, cpu_ov);
 
     tcg_temp_free_i64(t0);