Hi!
We have currently 3 different definitions of gcc_assert macro, one used most
of the time (unless --disable-checking) which evaluates the condition at
runtime and also checks it at runtime, then one for --disable-checking GCC 4.5+
which looks like
((void)(UNLIKELY (!(EXPR)) ? __builtin_unreachable (), 0 : 0))
and a fallback one
((void)(0 && (EXPR)))
Now, the last one actually doesn't evaluate any of the side-effects in the
argument, just quiets up unused var/parameter warnings.
I've tried to replace the middle definition with
({ [[assume (EXPR)]]; (void) 0; })
for compilers which support assume attribute and statement expressions
(surprisingly quite a few spots use gcc_assert inside of comma expressions),
but ran into PR117287, so for now such a change isn't being proposed.
The following patch attempts to move important side-effects from gcc_assert
arguments.
Bootstrapped/regtested on x86_64-linux and i686-linux with normal
--enable-checking=yes,rtl,extra, plus additionally I've attempted to do
x86_64-linux bootstrap with --disable-checking and gcc_assert changed to the
((void)(0 && (EXPR)))
version when --disable-checking. That version ran into spurious middle-end
warnings
../../gcc/../include/libiberty.h:733:36: error: argument to ‘alloca’ is too
large [-Werror=alloca-larger-than=]
../../gcc/tree-ssa-reassoc.cc:5659:20: note: in expansion of macro ‘XALLOCAVEC’
int op_num = ops.length ();
int op_normal_num = op_num;
gcc_assert (op_num > 0);
int stmt_num = op_num - 1;
gimple **stmts = XALLOCAVEC (gimple *, stmt_num);
where we have gcc_assert exactly to work-around middle-end warnings.
Guess I'd need to also disable -Werror for this experiment, which actually
isn't a problem with unmodified system.h, because even for
--disable-checking we use the __builtin_unreachable at least in
stage2/stage3 and so the warnings aren't emitted, and even if it used
[[assume ()]]; it would work too because in stage2/stage3 we could again
rely on assume and statement expression support.
Ok for trunk?
2024-10-25 Jakub Jelinek <ja...@redhat.com>
PR middle-end/117249
* tree-ssa-structalias.cc (insert_vi_for_tree): Move put calls out of
gcc_assert.
* lto-cgraph.cc (lto_symtab_encoder_delete_node): Likewise.
* gimple-ssa-strength-reduction.cc (get_alternative_base,
add_cand_for_stmt): Likewise.
* tree-eh.cc (add_stmt_to_eh_lp_fn): Likewise.
* except.cc (duplicate_eh_regions_1): Likewise.
* tree-ssa-reassoc.cc (insert_operand_rank): Likewise.
* config/nvptx/nvptx.cc (nvptx_expand_call): Use == rather than = in
gcc_assert.
* opts-common.cc (jobserver_info::disconnect): Call close outside of
gcc_assert and only check result in it.
(jobserver_info::return_token): Call write outside of gcc_assert and
only check result in it.
* genautomata.cc (output_default_latencies): Move j++ side-effect
outside of gcc_assert.
* tree-ssa-loop-ivopts.cc (get_alias_ptr_type_for_ptr_address): Use
== rather than = in gcc_assert.
* cgraph.cc (symbol_table::create_edge): Move ++edges_max_uid
side-effect outside of gcc_assert.
* pair-fusion.cc (pair_fusion_bb_info::fuse_pair): Call
restrict_movement outside of gcc_assert and only check result in it.
(pair_fusion::try_promote_writeback): Likewise.
--- gcc/tree-ssa-structalias.cc.jj 2024-10-02 13:30:14.982371644 +0200
+++ gcc/tree-ssa-structalias.cc 2024-10-23 10:42:02.584056165 +0200
@@ -2986,7 +2986,8 @@ static void
insert_vi_for_tree (tree t, varinfo_t vi)
{
gcc_assert (vi);
- gcc_assert (!vi_for_tree->put (t, vi));
+ bool existed = vi_for_tree->put (t, vi);
+ gcc_assert (!existed);
}
/* Find the variable info for tree T in VI_FOR_TREE. If T does not
--- gcc/lto-cgraph.cc.jj 2024-09-24 11:31:48.729621966 +0200
+++ gcc/lto-cgraph.cc 2024-10-23 10:43:11.013085410 +0200
@@ -155,7 +155,8 @@ lto_symtab_encoder_delete_node (lto_symt
last_node = encoder->nodes.pop ();
if (last_node.node != node)
{
- gcc_assert (encoder->map->put (last_node.node, index + 1));
+ bool existed = encoder->map->put (last_node.node, index + 1);
+ gcc_assert (existed);
/* Move the last element to the original spot of NODE. */
encoder->nodes[index] = last_node;
--- gcc/gimple-ssa-strength-reduction.cc.jj 2024-09-02 09:43:28.806148076
+0200
+++ gcc/gimple-ssa-strength-reduction.cc 2024-10-23 10:38:24.386151585
+0200
@@ -474,7 +474,8 @@ get_alternative_base (tree base)
aff.offset = 0;
expr = aff_combination_to_tree (&aff);
- gcc_assert (!alt_base_map->put (base, base == expr ? NULL : expr));
+ bool existed = alt_base_map->put (base, base == expr ? NULL : expr);
+ gcc_assert (!existed);
return expr == base ? NULL : expr;
}
@@ -792,7 +793,8 @@ base_cand_from_table (tree base_in)
static void
add_cand_for_stmt (gimple *gs, slsr_cand_t c)
{
- gcc_assert (!stmt_cand_map->put (gs, c));
+ bool existed = stmt_cand_map->put (gs, c);
+ gcc_assert (!existed);
}
/* Given PHI which contains a phi statement, determine whether it
--- gcc/tree-eh.cc.jj 2024-07-19 17:22:59.474096182 +0200
+++ gcc/tree-eh.cc 2024-10-23 10:41:17.686693092 +0200
@@ -76,7 +76,8 @@ add_stmt_to_eh_lp_fn (struct function *i
if (!get_eh_throw_stmt_table (ifun))
set_eh_throw_stmt_table (ifun, hash_map<gimple *, int>::create_ggc (31));
- gcc_assert (!get_eh_throw_stmt_table (ifun)->put (t, num));
+ bool existed = get_eh_throw_stmt_table (ifun)->put (t, num);
+ gcc_assert (!existed);
}
/* Add statement T in the current function (cfun) to EH landing pad NUM. */
--- gcc/except.cc.jj 2024-08-14 18:19:52.678848514 +0200
+++ gcc/except.cc 2024-10-23 10:35:03.365003334 +0200
@@ -541,7 +541,8 @@ duplicate_eh_regions_1 (struct duplicate
eh_region new_r;
new_r = gen_eh_region (old_r->type, outer);
- gcc_assert (!data->eh_map->put (old_r, new_r));
+ bool existed = data->eh_map->put (old_r, new_r);
+ gcc_assert (!existed);
switch (old_r->type)
{
@@ -586,7 +587,8 @@ duplicate_eh_regions_1 (struct duplicate
continue;
new_lp = gen_eh_landing_pad (new_r);
- gcc_assert (!data->eh_map->put (old_lp, new_lp));
+ bool existed = data->eh_map->put (old_lp, new_lp);
+ gcc_assert (!existed);
new_lp->post_landing_pad
= data->label_map (old_lp->post_landing_pad, data->label_map_data);
--- gcc/tree-ssa-reassoc.cc.jj 2024-09-25 16:06:33.849422365 +0200
+++ gcc/tree-ssa-reassoc.cc 2024-10-23 10:41:39.307386374 +0200
@@ -404,7 +404,8 @@ static inline void
insert_operand_rank (tree e, int64_t rank)
{
gcc_assert (rank > 0);
- gcc_assert (!operand_rank->put (e, rank));
+ bool existed = operand_rank->put (e, rank);
+ gcc_assert (!existed);
}
/* Given an expression E, return the rank of the expression. */
--- gcc/config/nvptx/nvptx.cc.jj 2024-10-24 10:29:13.535951981 +0200
+++ gcc/config/nvptx/nvptx.cc 2024-10-24 11:10:13.592174203 +0200
@@ -1901,7 +1901,7 @@ nvptx_expand_call (rtx retval, rtx addre
if (varargs)
XVECEXP (pat, 0, vec_pos++) = gen_rtx_USE (VOIDmode, varargs);
- gcc_assert (vec_pos = XVECLEN (pat, 0));
+ gcc_assert (vec_pos == XVECLEN (pat, 0));
nvptx_emit_forking (parallel, true);
emit_call_insn (pat);
--- gcc/opts-common.cc.jj 2024-10-24 10:29:14.009945200 +0200
+++ gcc/opts-common.cc 2024-10-24 11:25:17.323552274 +0200
@@ -2156,7 +2156,8 @@ jobserver_info::disconnect ()
{
if (!pipe_path.empty ())
{
- gcc_assert (close (pipefd) == 0);
+ int res = close (pipefd);
+ gcc_assert (res == 0);
pipefd = -1;
}
}
@@ -2181,5 +2182,6 @@ jobserver_info::return_token ()
{
int fd = pipe_path.empty () ? wfd : pipefd;
char c = 'G';
- gcc_assert (write (fd, &c, 1) == 1);
+ int res = write (fd, &c, 1);
+ gcc_assert (res == 1);
}
--- gcc/genautomata.cc.jj 2024-02-24 22:52:31.999449280 +0100
+++ gcc/genautomata.cc 2024-10-24 11:07:21.316602951 +0200
@@ -8348,7 +8348,8 @@ output_default_latencies (void)
if ((col = (col+1) % 8) == 0)
fputs ("\n ", output_file);
decl = description->decls[i];
- gcc_assert (j++ == DECL_INSN_RESERV (decl)->insn_num);
+ gcc_assert (j == DECL_INSN_RESERV (decl)->insn_num);
+ ++j;
fprintf (output_file, "% 4d,",
DECL_INSN_RESERV (decl)->default_latency);
}
--- gcc/tree-ssa-loop-ivopts.cc.jj 2024-10-14 19:39:48.494778534 +0200
+++ gcc/tree-ssa-loop-ivopts.cc 2024-10-24 11:03:47.991610401 +0200
@@ -7562,7 +7562,7 @@ get_alias_ptr_type_for_ptr_address (iv_u
case IFN_MASK_LEN_LOAD:
case IFN_MASK_LEN_STORE:
/* The second argument contains the correct alias type. */
- gcc_assert (use->op_p = gimple_call_arg_ptr (call, 0));
+ gcc_assert (use->op_p == gimple_call_arg_ptr (call, 0));
return TREE_TYPE (gimple_call_arg (call, 1));
default:
--- gcc/cgraph.cc.jj 2024-10-24 10:29:13.211956616 +0200
+++ gcc/cgraph.cc 2024-10-24 11:06:35.854243877 +0200
@@ -894,7 +894,8 @@ symbol_table::create_edge (cgraph_node *
edge->m_summary_id = -1;
edges_count++;
- gcc_assert (++edges_max_uid != 0);
+ ++edges_max_uid;
+ gcc_assert (edges_max_uid != 0);
edge->m_uid = edges_max_uid;
edge->aux = NULL;
edge->caller = caller;
--- gcc/pair-fusion.cc.jj 2024-10-22 17:09:09.372091098 +0200
+++ gcc/pair-fusion.cc 2024-10-24 11:13:07.023744574 +0200
@@ -1962,7 +1962,10 @@ pair_fusion_bb_info::fuse_pair (bool loa
auto ignore = ignore_changing_insns (changes);
for (unsigned i = 0; i < changes.length (); i++)
- gcc_assert (rtl_ssa::restrict_movement (*changes[i], ignore));
+ {
+ bool ok = rtl_ssa::restrict_movement (*changes[i], ignore);
+ gcc_assert (ok);
+ }
// Check the pair pattern is recog'd.
if (!rtl_ssa::recog (attempt, *pair_change, ignore))
@@ -3053,7 +3056,10 @@ pair_fusion::try_promote_writeback (insn
auto ignore = ignore_changing_insns (changes);
for (unsigned i = 0; i < ARRAY_SIZE (changes); i++)
- gcc_assert (rtl_ssa::restrict_movement (*changes[i], ignore));
+ {
+ bool ok = rtl_ssa::restrict_movement (*changes[i], ignore);
+ gcc_assert (ok);
+ }
if (!rtl_ssa::recog (attempt, pair_change, ignore))
{
Jakub
