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.
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: Richard Henderson <r...@twiddle.net>
Signed-off-by: Aurelien Jarno <aurel...@aurel32.net>
---
tcg/optimize.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/tcg/optimize.c b/tcg/optimize.c
index d66373d..18b7bc3 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -347,9 +347,11 @@ static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg
x, TCGArg y)
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;
@@ -839,6 +841,14 @@ void tcg_optimize(TCGContext *s)
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:
+ 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. */
--
2.1.4
