Hi. The patch prevents crashes caused by fact that do_per_function_toporder uses get_uid () to register all dead cgraph_nodes. That does not work now as cgraph_nodes are directly released via ggc_free and so that one will see a garbage here. Second steps is to register all cgraph hooks and correctly hold add removed nodes. Doing that we'll not need the GGC nodes array.
Patch can bootstrap on x86_64-linux-gnu and survives regression tests. I can also build xalancbmk with -O2 -ffast-math where I previously saw the ICE. Ready to be installed? Thanks, Martin gcc/ChangeLog: 2019-08-09 Martin Liska <mli...@suse.cz> PR ipa/91404 * passes.c (order): Remove. (uid_hash_t): Likewise). (remove_cgraph_node_from_order): Remove from set of pointers (cgraph_node *). (insert_cgraph_node_to_order): New. (duplicate_cgraph_node_to_order): New. (do_per_function_toporder): Register all 3 cgraph hooks. Skip removed_nodes now as we know about all of them. --- gcc/passes.c | 69 +++++++++++++++++++++++++++++++++------------------- 1 file changed, 44 insertions(+), 25 deletions(-)
diff --git a/gcc/passes.c b/gcc/passes.c index bd56004d909..934ae0b52ca 100644 --- a/gcc/passes.c +++ b/gcc/passes.c @@ -1646,24 +1646,39 @@ do_per_function (void (*callback) (function *, void *data), void *data) } } -/* Because inlining might remove no-longer reachable nodes, we need to - keep the array visible to garbage collector to avoid reading collected - out nodes. */ -static int nnodes; -static GTY ((length ("nnodes"))) cgraph_node **order; - -#define uid_hash_t hash_set<int_hash <int, 0, -1> > - /* Hook called when NODE is removed and therefore should be excluded from order vector. DATA is a hash set with removed nodes. */ static void remove_cgraph_node_from_order (cgraph_node *node, void *data) { - uid_hash_t *removed_nodes = (uid_hash_t *)data; - removed_nodes->add (node->get_uid ()); + hash_set<cgraph_node *> *removed_nodes = (hash_set<cgraph_node *> *)data; + removed_nodes->add (node); +} + +/* Hook called when NODE is insert and therefore should be + excluded from removed_nodes. DATA is a hash set with removed nodes. */ + +static void +insert_cgraph_node_to_order (cgraph_node *node, void *data) +{ + hash_set<cgraph_node *> *removed_nodes = (hash_set<cgraph_node *> *)data; + removed_nodes->remove (node); } +/* Hook called when NODE is duplicated and therefore should be + excluded from removed_nodes. DATA is a hash set with removed nodes. */ + +static void +duplicate_cgraph_node_to_order (cgraph_node *node, cgraph_node *node2, + void *data) +{ + hash_set<cgraph_node *> *removed_nodes = (hash_set<cgraph_node *> *)data; + gcc_checking_assert (!removed_nodes->contains (node)); + removed_nodes->remove (node2); +} + + /* If we are in IPA mode (i.e., current_function_decl is NULL), call function CALLBACK for every function in the call graph. Otherwise, call CALLBACK on the current function. @@ -1677,26 +1692,33 @@ do_per_function_toporder (void (*callback) (function *, void *data), void *data) callback (cfun, data); else { - cgraph_node_hook_list *hook; - uid_hash_t removed_nodes; - gcc_assert (!order); - order = ggc_vec_alloc<cgraph_node *> (symtab->cgraph_count); + cgraph_node_hook_list *removal_hook; + cgraph_node_hook_list *insertion_hook; + cgraph_2node_hook_list *duplication_hook; + hash_set<cgraph_node *> removed_nodes; + unsigned nnodes = symtab->cgraph_count; + cgraph_node **order = XNEWVEC (cgraph_node *, nnodes); nnodes = ipa_reverse_postorder (order); for (i = nnodes - 1; i >= 0; i--) order[i]->process = 1; - hook = symtab->add_cgraph_removal_hook (remove_cgraph_node_from_order, - &removed_nodes); + removal_hook + = symtab->add_cgraph_removal_hook (remove_cgraph_node_from_order, + &removed_nodes); + insertion_hook + = symtab->add_cgraph_insertion_hook (insert_cgraph_node_to_order, + &removed_nodes); + duplication_hook + = symtab->add_cgraph_duplication_hook (duplicate_cgraph_node_to_order, + &removed_nodes); for (i = nnodes - 1; i >= 0; i--) { cgraph_node *node = order[i]; /* Function could be inlined and removed as unreachable. */ - if (node == NULL || removed_nodes.contains (node->get_uid ())) + if (node == NULL || removed_nodes.contains (node)) continue; - /* Allow possibly removed nodes to be garbage collected. */ - order[i] = NULL; node->process = 0; if (node->has_gimple_body_p ()) { @@ -1706,11 +1728,10 @@ do_per_function_toporder (void (*callback) (function *, void *data), void *data) pop_cfun (); } } - symtab->remove_cgraph_removal_hook (hook); + symtab->remove_cgraph_removal_hook (removal_hook); + symtab->remove_cgraph_insertion_hook (insertion_hook); + symtab->remove_cgraph_duplication_hook (duplication_hook); } - ggc_free (order); - order = NULL; - nnodes = 0; } /* Helper function to perform function body dump. */ @@ -3046,5 +3067,3 @@ function_called_by_processed_nodes_p (void) } return e != NULL; } - -#include "gt-passes.h"