procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

stmt.c (expand_start_null_loop): New.

Browse source 
* stmt.c (expand_start_null_loop): New.
        (expand_end_null_loop): New.
        * c-semantics.c (genrtl_do_stmt): Use them.
        * tree.h: Declare them.

From-SVN: r37186
This commit is contained in:
Richard Henderson 2000-11-01 02:28:32 -08:00 • committed by Richard Henderson
parent faafaee632
commit f0de0c5d17
4 changed files with 51 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
gcc/ChangeLog
View file

@ -1,3 +1,10 @@
2000-11-01 Richard Henderson <rth@redhat.com>
* stmt.c (expand_start_null_loop): New.
(expand_end_null_loop): New.
* c-semantics.c (genrtl_do_stmt): Use them.
* tree.h: Declare them.
2000-11-01 Richard Henderson <rth@redhat.com>
* cppmain.c (scan_buffer): Don't avoid paste for assembly.

6
gcc/c-semantics.c
View file

@ -487,7 +487,11 @@ genrtl_do_stmt (t)
avoids cluttering the rtl with dummy loop notes, which can affect
alignment of adjacent labels. */
if (integer_zerop (cond))
expand_stmt (DO_BODY (t));
{
expand_start_null_loop ();
expand_stmt (DO_BODY (t));
expand_end_null_loop ();
}
else
{
emit_nop ();

37
gcc/stmt.c
View file

@ -2294,6 +2294,30 @@ expand_start_loop_continue_elsewhere (exit_flag)
return thisloop;
}
/* Begin a null, aka do { } while (0) "loop". But since the contents
of said loop can still contain a break, we must frob the loop nest. */
struct nesting *
expand_start_null_loop ()
{
register struct nesting *thisloop = ALLOC_NESTING ();
/* Make an entry on loop_stack for the loop we are entering. */
thisloop->next = loop_stack;
thisloop->all = nesting_stack;
thisloop->depth = ++nesting_depth;
thisloop->data.loop.start_label = emit_note (NULL, NOTE_INSN_DELETED);
thisloop->data.loop.end_label = gen_label_rtx ();
thisloop->data.loop.alt_end_label = NULL_RTX;
thisloop->data.loop.continue_label = NULL_RTX;
thisloop->exit_label = thisloop->data.loop.end_label;
loop_stack = thisloop;
nesting_stack = thisloop;
return thisloop;
}
/* Specify the continuation point for a loop started with
expand_start_loop_continue_elsewhere.
Use this at the point in the code to which a continue statement
@ -2620,6 +2644,19 @@ expand_end_loop ()
last_expr_type = 0;
}
/* Finish a null loop, aka do { } while (0). */
void
expand_end_null_loop ()
{
do_pending_stack_adjust ();
emit_label (loop_stack->data.loop.end_label);
POPSTACK (loop_stack);
last_expr_type = 0;
}
/* Generate a jump to the current loop's continue-point.
This is usually the top of the loop, but may be specified
explicitly elsewhere. If not currently inside a loop,

2
gcc/tree.h
View file

@ -2460,8 +2460,10 @@ extern void expand_start_else PARAMS ((void));
extern void expand_start_elseif PARAMS ((tree));
extern struct nesting *expand_start_loop PARAMS ((int));
extern struct nesting *expand_start_loop_continue_elsewhere PARAMS ((int));
extern struct nesting *expand_start_null_loop PARAMS ((void));
extern void expand_loop_continue_here PARAMS ((void));
extern void expand_end_loop PARAMS ((void));
extern void expand_end_null_loop PARAMS ((void));
extern int expand_continue_loop PARAMS ((struct nesting *));
extern int expand_exit_loop PARAMS ((struct nesting *));
extern int expand_exit_loop_if_false PARAMS ((struct nesting *,