diff options
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/expr.c | 30 |
2 files changed, 23 insertions, 12 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 8271924..ec60f84 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2015-10-21 Richard Henderson <rth@redhat.com> + + * expr.c (expand_expr_real_2): Use convert_modes on disjoint + address spaces. + 2015-10-21 Richard Sandiford <richard.sandiford@arm.com> * builtins.c (fold_builtin_cabs): Delete. @@ -8171,34 +8171,40 @@ expand_expr_real_2 (sepops ops, rtx target, machine_mode tmode, case ADDR_SPACE_CONVERT_EXPR: { tree treeop0_type = TREE_TYPE (treeop0); - addr_space_t as_to; - addr_space_t as_from; gcc_assert (POINTER_TYPE_P (type)); gcc_assert (POINTER_TYPE_P (treeop0_type)); - as_to = TYPE_ADDR_SPACE (TREE_TYPE (type)); - as_from = TYPE_ADDR_SPACE (TREE_TYPE (treeop0_type)); + addr_space_t as_to = TYPE_ADDR_SPACE (TREE_TYPE (type)); + addr_space_t as_from = TYPE_ADDR_SPACE (TREE_TYPE (treeop0_type)); /* Conversions between pointers to the same address space should have been implemented via CONVERT_EXPR / NOP_EXPR. */ gcc_assert (as_to != as_from); + op0 = expand_expr (treeop0, NULL_RTX, VOIDmode, modifier); + /* Ask target code to handle conversion between pointers to overlapping address spaces. */ if (targetm.addr_space.subset_p (as_to, as_from) || targetm.addr_space.subset_p (as_from, as_to)) { - op0 = expand_expr (treeop0, NULL_RTX, VOIDmode, modifier); op0 = targetm.addr_space.convert (op0, treeop0_type, type); - gcc_assert (op0); - return op0; } - - /* For disjoint address spaces, converting anything but - a null pointer invokes undefined behaviour. We simply - always return a null pointer here. */ - return CONST0_RTX (mode); + else + { + /* For disjoint address spaces, converting anything but a null + pointer invokes undefined behaviour. We truncate or extend the + value as if we'd converted via integers, which handles 0 as + required, and all others as the programmer likely expects. */ +#ifndef POINTERS_EXTEND_UNSIGNED + const int POINTERS_EXTEND_UNSIGNED = 1; +#endif + op0 = convert_modes (mode, TYPE_MODE (treeop0_type), + op0, POINTERS_EXTEND_UNSIGNED); + } + gcc_assert (op0); + return op0; } case POINTER_PLUS_EXPR: |