Like my recent patch to add ovl_range and lkp_range in the C++ front end,
this patch adds the tsi_range adaptor for using C++11 range-based 'for' with
a STATEMENT_LIST, e.g.
for (tree stmt : tsi_range (stmt_list)) { ... }
This also involves adding some operators to tree_stmt_iterator that are
needed for range-for iterators, and should also be useful in code that uses
the iterators directly.
The patch updates the suitable loops in the C++ front end, but does not
touch any loops elsewhere in the compiler.
gcc/ChangeLog:
* tree-iterator.h (struct tree_stmt_iterator): Add operator++,
operator--, operator*, operator==, and operator!=.
(class tsi_range): New.
gcc/cp/ChangeLog:
* constexpr.c (build_data_member_initialization): Use tsi_range.
(build_constexpr_constructor_member_initializers): Likewise.
(constexpr_fn_retval, cxx_eval_statement_list): Likewise.
(potential_constant_expression_1): Likewise.
* coroutines.cc (await_statement_expander): Likewise.
(await_statement_walker): Likewise.
* module.cc (trees_out::core_vals): Likewise.
* pt.c (tsubst_expr): Likewise.
* semantics.c (set_cleanup_locs): Likewise.
---
gcc/tree-iterator.h | 28 +++++++++++++++++++++++-----
gcc/cp/constexpr.c | 42 ++++++++++++++----------------------------
gcc/cp/coroutines.cc | 10 ++++------
gcc/cp/module.cc | 5 ++---
gcc/cp/pt.c | 5 ++---
gcc/cp/semantics.c | 5 ++---
6 files changed, 47 insertions(+), 48 deletions(-)
diff --git a/gcc/tree-iterator.h b/gcc/tree-iterator.h
index 076fff8644c..f57456bb473 100644
--- a/gcc/tree-iterator.h
+++ b/gcc/tree-iterator.h
@@ -1,4 +1,4 @@
-/* Iterator routines for manipulating GENERIC tree statement list.
+/* Iterator routines for manipulating GENERIC tree statement list. -*- C++ -*-
Copyright (C) 2003-2021 Free Software Foundation, Inc.
Contributed by Andrew MacLeod <amacl...@redhat.com>
@@ -32,6 +32,13 @@ along with GCC; see the file COPYING3. If not see
struct tree_stmt_iterator {
struct tree_statement_list_node *ptr;
tree container;
+
+ bool operator== (tree_stmt_iterator b) const
+ { return b.ptr == ptr && b.container == container; }
+ bool operator!= (tree_stmt_iterator b) const { return !(*this == b); }
+ tree_stmt_iterator &operator++ () { ptr = ptr->next; return *this; }
+ tree_stmt_iterator &operator-- () { ptr = ptr->prev; return *this; }
+ tree &operator* () { return ptr->stmt; }
};
static inline tree_stmt_iterator
@@ -71,27 +78,38 @@ tsi_one_before_end_p (tree_stmt_iterator i)
static inline void
tsi_next (tree_stmt_iterator *i)
{
- i->ptr = i->ptr->next;
+ ++(*i);
}
static inline void
tsi_prev (tree_stmt_iterator *i)
{
- i->ptr = i->ptr->prev;
+ --(*i);
}
static inline tree *
tsi_stmt_ptr (tree_stmt_iterator i)
{
- return &i.ptr->stmt;
+ return &(*i);
}
static inline tree
tsi_stmt (tree_stmt_iterator i)
{
- return i.ptr->stmt;
+ return *i;
}
+/* Make tree_stmt_iterator work as a C++ range, e.g.
+ for (tree stmt : tsi_range (stmt_list)) { ... } */
+class tsi_range
+{
+ tree t;
+ public:
+ tsi_range (tree t): t(t) { }
+ tree_stmt_iterator begin() { return tsi_start (t); }
+ tree_stmt_iterator end() { return { nullptr, t }; }
+};
+
enum tsi_iterator_update
{
TSI_NEW_STMT, /* Only valid when single statement is added,
move
diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c
index 9481a5bfd3c..260b0122f59 100644
--- a/gcc/cp/constexpr.c
+++ b/gcc/cp/constexpr.c
@@ -330,12 +330,9 @@ build_data_member_initialization (tree t,
vec<constructor_elt, va_gc> **vec)
return false;
if (TREE_CODE (t) == STATEMENT_LIST)
{
- tree_stmt_iterator i;
- for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
- {
- if (! build_data_member_initialization (tsi_stmt (i), vec))
- return false;
- }
+ for (tree stmt : tsi_range (t))
+ if (! build_data_member_initialization (stmt, vec))
+ return false;
return true;
}
if (TREE_CODE (t) == CLEANUP_STMT)
@@ -577,10 +574,9 @@ build_constexpr_constructor_member_initializers (tree
type, tree body)
break;
case STATEMENT_LIST:
- for (tree_stmt_iterator i = tsi_start (body);
- !tsi_end_p (i); tsi_next (&i))
+ for (tree stmt : tsi_range (body))
{
- body = tsi_stmt (i);
+ body = stmt;
if (TREE_CODE (body) == BIND_EXPR)
break;
}
@@ -617,10 +613,9 @@ build_constexpr_constructor_member_initializers (tree
type, tree body)
}
else if (TREE_CODE (body) == STATEMENT_LIST)
{
- tree_stmt_iterator i;
- for (i = tsi_start (body); !tsi_end_p (i); tsi_next (&i))
+ for (tree stmt : tsi_range (body))
{
- ok = build_data_member_initialization (tsi_stmt (i), &vec);
+ ok = build_data_member_initialization (stmt, &vec);
if (!ok)
break;
}
@@ -675,11 +670,10 @@ constexpr_fn_retval (tree body)
{
case STATEMENT_LIST:
{
- tree_stmt_iterator i;
tree expr = NULL_TREE;
- for (i = tsi_start (body); !tsi_end_p (i); tsi_next (&i))
+ for (tree stmt : tsi_range (body))
{
- tree s = constexpr_fn_retval (tsi_stmt (i));
+ tree s = constexpr_fn_retval (stmt);
if (s == error_mark_node)
return error_mark_node;
else if (s == NULL_TREE)
@@ -5772,7 +5766,6 @@ cxx_eval_statement_list (const constexpr_ctx *ctx, tree t,
bool *non_constant_p, bool *overflow_p,
tree *jump_target)
{
- tree_stmt_iterator i;
tree local_target;
/* In a statement-expression we want to return the last value.
For empty statement expression return void_node. */
@@ -5782,9 +5775,8 @@ cxx_eval_statement_list (const constexpr_ctx *ctx, tree t,
local_target = NULL_TREE;
jump_target = &local_target;
}
- for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
+ for (tree stmt : tsi_range (t))
{
- tree stmt = tsi_stmt (i);
/* We've found a continue, so skip everything until we reach
the label its jumping to. */
if (continues (jump_target))
@@ -8283,16 +8275,10 @@ potential_constant_expression_1 (tree t, bool
want_rval, bool strict, bool now,
}
case STATEMENT_LIST:
- {
- tree_stmt_iterator i;
- for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
- {
- if (!RECUR (tsi_stmt (i), any))
- return false;
- }
- return true;
- }
- break;
+ for (tree stmt : tsi_range (t))
+ if (!RECUR (stmt, any))
+ return false;
+ return true;
case MODIFY_EXPR:
if (cxx_dialect < cxx14)
diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc
index dbd703a67cc..9b498f9d0b4 100644
--- a/gcc/cp/coroutines.cc
+++ b/gcc/cp/coroutines.cc
@@ -1771,10 +1771,9 @@ await_statement_expander (tree *stmt, int *do_subtree,
void *d)
return NULL_TREE; /* Just process the sub-trees. */
else if (TREE_CODE (*stmt) == STATEMENT_LIST)
{
- tree_stmt_iterator i;
- for (i = tsi_start (*stmt); !tsi_end_p (i); tsi_next (&i))
+ for (tree &s : tsi_range (*stmt))
{
- res = cp_walk_tree (tsi_stmt_ptr (i), await_statement_expander,
+ res = cp_walk_tree (&s, await_statement_expander,
d, NULL);
if (res)
return res;
@@ -3523,10 +3522,9 @@ await_statement_walker (tree *stmt, int *do_subtree,
void *d)
}
else if (TREE_CODE (*stmt) == STATEMENT_LIST)
{
- tree_stmt_iterator i;
- for (i = tsi_start (*stmt); !tsi_end_p (i); tsi_next (&i))
+ for (tree &s : tsi_range (*stmt))
{
- res = cp_walk_tree (tsi_stmt_ptr (i), await_statement_walker,
+ res = cp_walk_tree (&s, await_statement_walker,
d, NULL);
if (res)
return res;
diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index 02c19f55548..f0fb0144706 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -6094,9 +6094,8 @@ trees_out::core_vals (tree t)
break;
case STATEMENT_LIST:
- for (tree_stmt_iterator iter = tsi_start (t);
- !tsi_end_p (iter); tsi_next (&iter))
- if (tree stmt = tsi_stmt (iter))
+ for (tree stmt : tsi_range (t))
+ if (stmt)
WT (stmt);
WT (NULL_TREE);
break;
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 116bdd2e42a..ad140cfd586 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -18234,9 +18234,8 @@ tsubst_expr (tree t, tree args, tsubst_flags_t
complain, tree in_decl,
{
case STATEMENT_LIST:
{
- tree_stmt_iterator i;
- for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
- RECUR (tsi_stmt (i));
+ for (tree stmt : tsi_range (t))
+ RECUR (stmt);
break;
}
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 6224f49f189..2912efad9be 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -613,9 +613,8 @@ set_cleanup_locs (tree stmts, location_t loc)
set_cleanup_locs (CLEANUP_BODY (stmts), loc);
}
else if (TREE_CODE (stmts) == STATEMENT_LIST)
- for (tree_stmt_iterator i = tsi_start (stmts);
- !tsi_end_p (i); tsi_next (&i))
- set_cleanup_locs (tsi_stmt (i), loc);
+ for (tree stmt : tsi_range (stmts))
+ set_cleanup_locs (stmt, loc);
}
/* Finish a scope. */
base-commit: 3c65858787dc52b65b26fa7018587c01510f442c
prerequisite-patch-id: 7ce9dff1f7d449f4a13fb882bf7b1a962a56de95
--
2.27.0
