On Thu, Jun 19, 2025 at 05:59:10PM +0800, Yang Yujie wrote:
> --- a/gcc/expr.cc
> +++ b/gcc/expr.cc
> @@ -11268,6 +11268,10 @@ expand_expr_real_1 (tree exp, rtx target,
> machine_mode tmode,
> tree ssa_name = NULL_TREE;
> gimple *g;
>
> + type = TREE_TYPE (exp);
> + mode = TYPE_MODE (type);
> + unsignedp = TYPE_UNSIGNED (type);
> +
> /* Some ABIs define padding bits in _BitInt uninitialized. Normally, RTL
> expansion sign/zero extends integral types with less than mode precision
> when reading from bit-fields and after arithmetic operations (see
> @@ -11278,8 +11282,10 @@ expand_expr_real_1 (tree exp, rtx target,
> machine_mode tmode,
> objects in memory, or function arguments, return value). Because we
> internally extend after arithmetic operations, we can avoid doing that
> when reading from SSA_NAMEs of vars. */
> +
> #define EXTEND_BITINT(expr) \
> ((TREE_CODE (type) == BITINT_TYPE \
> + && !bitint_type_info.extended \
> && reduce_bit_field
> \
> && mode != BLKmode
> \
> && modifier != EXPAND_MEMORY \
> @@ -11288,9 +11294,13 @@ expand_expr_real_1 (tree exp, rtx target,
> machine_mode tmode,
> && modifier != EXPAND_CONST_ADDRESS) \
> ? reduce_to_bit_field_precision ((expr), NULL_RTX, type) : (expr))
>
> - type = TREE_TYPE (exp);
> - mode = TYPE_MODE (type);
> - unsignedp = TYPE_UNSIGNED (type);
> + struct bitint_info bitint_type_info;
> + if (TREE_CODE (type) == BITINT_TYPE)
> + {
> + bool ok = targetm.c.bitint_type_info (TYPE_PRECISION (type),
> + &bitint_type_info);
> + gcc_assert (ok);
> + }
This needs to be cached, having the target hook being called for expansion
of anything with bitint type is too costly.
Jakub
