diff options
| author | dnovillo <dnovillo@138bc75d-0d04-0410-961f-82ee72b054a4> | 2005-02-01 20:30:07 +0000 |
|---|---|---|
| committer | dnovillo <dnovillo@138bc75d-0d04-0410-961f-82ee72b054a4> | 2005-02-01 20:30:07 +0000 |
| commit | 1e1a4c8c01aaeaeab9ebfb0dcf901542f968339c (patch) | |
| tree | 87292513a1b836b5850299e91904214e71fb9556 /gcc/testsuite/gcc.dg/pr19633.c | |
| parent | 06c1e1603fb0591f620322f6205c60ea8112282e (diff) | |
| download | gcc-1e1a4c8c01aaeaeab9ebfb0dcf901542f968339c.tar.gz | |
PR tree-optimization/19633
* tree-flow.h (struct ptr_info_def): Add field 'pt_null'.
* tree-ssa-alias.c (init_alias_info): Initialize.
(merge_pointed_to_info): Set.
(add_pointed_to_expr): Set pt_null if EXPR is a NULL pointer.
(dump_points_to_info_for): Show value of pt_null.
(struct count_ptr_d): Declare.
(find_ptr_dereference): Remove.
(ptr_is_dereferenced_by): Remove.
(count_ptr_derefs): New local function.
(count_uses_and_derefs): New local function.
(compute_points_to_and_addr_escape): Call it. If the number
of dereferences is greater than zero, mark the pointer as
dereferenced. If there are fewer dereferences than uses of
the pointer, the pointer's value escapes.
testsuite/ChangeLog
PR tree-optimization/19633
* testsuite/gcc.dg/pr19633-1.c: New test.
* testsuite/gcc.dg/pr19633.c: Tweak to make pointer point
to NULL or a symbol.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@94558 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/testsuite/gcc.dg/pr19633.c')
| -rw-r--r-- | gcc/testsuite/gcc.dg/pr19633.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/gcc/testsuite/gcc.dg/pr19633.c b/gcc/testsuite/gcc.dg/pr19633.c index 4e18375656f..fda0df6c5fa 100644 --- a/gcc/testsuite/gcc.dg/pr19633.c +++ b/gcc/testsuite/gcc.dg/pr19633.c @@ -15,12 +15,21 @@ struct T void foo (int a, struct T b) { - struct S x; - struct S *c = &x; + struct S *c = 0; + if (a) c = &b.s; + b.s.w = 3; + + /* Since 'c' may be pointing to NULL here, we used to flag it as + pointing anywhere, which was forcing the aliaser to mark as + call-clobbered every other variable pointed-to by 'c' ('b' in + this case). This, in turn, caused the insertion of V_MAY_DEFs + for 'b' at this call-site, which prevented constant propagation + from 'b.s.w = 3' to 'if (b.s.w != 3)'. */ bar (*c, a); + if (b.s.w != 3) link_error (); } |