OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

c-typeck.c (c_finish_loop): Improve initial implementations for loops whose conditions are known at...

Browse Source 
* c-typeck.c (c_finish_loop): Improve initial implementations
	for loops whose conditions are known at compile-time.

From-SVN: r91750
This commit is contained in:
Roger Sayle 2004-12-05 15:31:02 +00:00 committed by Roger Sayle
parent 118f3b19a3
commit 28af952a24
2 changed files with 17 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
gcc/ChangeLog
View File

@ -1,3 +1,8 @@
2004-12-05 Roger Sayle <roger@eyesopen.com>
* c-typeck.c (c_finish_loop): Improve initial implementations
for loops whose conditions are known at compile-time.
2004-12-05 Kazu Hirata <kazu@cs.umass.edu>
* builtins.c: Fix comment typos.

17
gcc/c-typeck.c
View File

@ -6659,10 +6659,17 @@ c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
{
tree entry = NULL, exit = NULL, t;
/* Detect do { ... } while (0) and don't generate loop construct. */
if (cond && !cond_is_first && integer_zerop (cond))
cond = NULL;
if (cond_is_first || cond)
/* If the condition is zero don't generate a loop construct. */
if (cond && integer_zerop (cond))
{
if (cond_is_first)
{
t = build_and_jump (&blab);
SET_EXPR_LOCATION (t, start_locus);
add_stmt (t);
}
}
else
{
tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
@ -6671,7 +6678,7 @@ c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
then we just build a jump back to the top. */
exit = build_and_jump (&LABEL_EXPR_LABEL (top));
if (cond)
if (cond && !integer_nonzerop (cond))
{
/* Canonicalize the loop condition to the end. This means
generating a branch to the loop condition. Reuse the