commit 8bcb5c8f34f9215d4f88f388c7ff14c9bd5cecd3
author Aurelien Jarno <aurelien@aurel32.net> Mon Jul 27 12:41:45 2015 +0200
committer Richard Henderson <rth@twiddle.net> Mon Aug 24 11:10:54 2015 -0700
tree 8f0dcb356b6144ce20c61899c1267fc9c6db6ebb
parent 4f2331e5b67af8172419eb1c8db510b497b30a7b

tcg/optimize: add optimizations for ext_i32_i64 and extu_i32_i64 ops

They behave the same as ext32s_i64 and ext32u_i64 from the constant
folding and zero propagation point of view, except that they can't
be replaced by a mov, so we don't compute the affected value.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>

tcg/optimize.c

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 47f4147..1804605 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -343,9 +343,11 @@
     CASE_OP_32_64(ext16u):
         return (uint16_t)x;
 
+    case INDEX_op_ext_i32_i64:
     case INDEX_op_ext32s_i64:
         return (int32_t)x;
 
+    case INDEX_op_extu_i32_i64:
     case INDEX_op_ext32u_i64:
         return (uint32_t)x;
 
@@ -837,6 +839,15 @@
             mask = temps[args[1]].mask & mask;
             break;
 
+        case INDEX_op_ext_i32_i64:
+            if ((temps[args[1]].mask & 0x80000000) != 0) {
+                break;
+            }
+        case INDEX_op_extu_i32_i64:
+            /* We do not compute affected as it is a size changing op.  */
+            mask = (uint32_t)temps[args[1]].mask;
+            break;
+
         CASE_OP_32_64(andc):
             /* Known-zeros does not imply known-ones.  Therefore unless
                args[2] is constant, we can't infer anything from it.  */
@@ -1015,6 +1026,8 @@
         CASE_OP_32_64(ext16u):
         case INDEX_op_ext32s_i64:
         case INDEX_op_ext32u_i64:
+        case INDEX_op_ext_i32_i64:
+        case INDEX_op_extu_i32_i64:
             if (temp_is_const(args[1])) {
                 tmp = do_constant_folding(opc, temps[args[1]].val, 0);
                 tcg_opt_gen_movi(s, op, args, args[0], tmp);