On Fri, Mar 11, 2011 at 5:23 AM, Nathan Froyd <froy...@codesourcery.com> wrote:
> This patch begins a subseries of patches aimed at removing TREE_CHAIN
> from expression trees. tree-cfg.c uses TREE_CHAIN for some analysis
> steps on CASE_LABEL_EXPRs. I looked at this for a while, thinking it'd
> be easy to use VECs instead, but AFAICS, it wasn't. I went for the next
> best thing, hiding TREE_CHAIN usage behind CASE_CHAIN; doing this will
> enable swapping out the TREE_CHAIN for a TREE_OPERAND at a later point.
Ok for 4.7.
Thanks,
Richard.
> -Nathan
>
> * tree.h (CASE_CHAIN): Define.
> * tree-cfg.c (edge_to_cases_cleanup, get_cases_for_edge): Use it.
> (gimple_redirect_edge_and_branch): Likewise.
>
> diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
> index 1f533a3..bdce4cb 100644
> --- a/gcc/tree-cfg.c
> +++ b/gcc/tree-cfg.c
> @@ -838,8 +838,8 @@ edge_to_cases_cleanup (const void *key ATTRIBUTE_UNUSED,
> void **value,
>
> for (t = (tree) *value; t; t = next)
> {
> - next = TREE_CHAIN (t);
> - TREE_CHAIN (t) = NULL;
> + next = CASE_CHAIN (t);
> + CASE_CHAIN (t) = NULL;
> }
>
> *value = NULL;
> @@ -922,7 +922,7 @@ get_cases_for_edge (edge e, gimple t)
> /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
> a new chain. */
> slot = pointer_map_insert (edge_to_cases, this_edge);
> - TREE_CHAIN (elt) = (tree) *slot;
> + CASE_CHAIN (elt) = (tree) *slot;
> *slot = elt;
> }
>
> @@ -4900,7 +4900,7 @@ gimple_redirect_edge_and_branch (edge e, basic_block
> dest)
> {
> last = cases;
> CASE_LABEL (cases) = label;
> - cases = TREE_CHAIN (cases);
> + cases = CASE_CHAIN (cases);
> }
>
> /* If there was already an edge in the CFG, then we need
> @@ -4909,8 +4909,8 @@ gimple_redirect_edge_and_branch (edge e, basic_block
> dest)
> {
> tree cases2 = get_cases_for_edge (e2, stmt);
>
> - TREE_CHAIN (last) = TREE_CHAIN (cases2);
> - TREE_CHAIN (cases2) = first;
> + CASE_CHAIN (last) = CASE_CHAIN (cases2);
> + CASE_CHAIN (cases2) = first;
> }
> bitmap_set_bit (touched_switch_bbs, gimple_bb (stmt)->index);
> }
> diff --git a/gcc/tree.h b/gcc/tree.h
> index 35479f9..58b3b9d 100644
> --- a/gcc/tree.h
> +++ b/gcc/tree.h
> @@ -1689,6 +1689,7 @@ extern void protected_set_expr_location (tree,
> location_t);
> #define CASE_LOW(NODE) TREE_OPERAND (CASE_LABEL_EXPR_CHECK
> (NODE), 0)
> #define CASE_HIGH(NODE) TREE_OPERAND (CASE_LABEL_EXPR_CHECK
> (NODE), 1)
> #define CASE_LABEL(NODE) TREE_OPERAND (CASE_LABEL_EXPR_CHECK
> (NODE), 2)
> +#define CASE_CHAIN(NODE) TREE_CHAIN (CASE_LABEL_EXPR_CHECK
> (NODE))
>
> /* The operands of a TARGET_MEM_REF. Operands 0 and 1 have to match
> corresponding MEM_REF operands. */
> --
> 1.7.0.4
>
>
