diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 14 | ||||
| -rw-r--r-- | gcc/gimple-ssa.h | 3 | ||||
| -rw-r--r-- | gcc/passes.c | 9 | ||||
| -rw-r--r-- | gcc/tree-ssanames.c | 24 | ||||
| -rw-r--r-- | gcc/tree-ssanames.h | 1 |
5 files changed, 49 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ba82953..dd723b8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,17 @@ +2015-09-30 Bernd Schmidt <bernds@redhat.com> + + * gimple-ssa.h (gimple_df): Add free_ssanames_queue field. + * passes.c: Include tree-ssanames.h. + (execute_function_todo): Flush the pending free SSA_NAMEs after + eliminating unreachable basic blocks. + * tree-ssanames.c (FREE_SSANAMES_QUEUE): new. + (init_ssanames): Initialize FREE_SSANAMES_QUEUE. + (fini_ssanames): Finalize FREE_SSANAMES_QUEUE. + (flush_ssanames_freelist): New function. + (release_ssaname_fn): Put released names on the queue. + (pass_release_ssa_names::execute): Call flush_ssanames_freelist. + * tree-ssanames.h (flush_ssanames_freelist): Declare. + 2015-09-30 Thomas Schwinge <thomas@codesourcery.com> * config/i386/intelmic-mkoffload.c (main): Parse "-v" flag. diff --git a/gcc/gimple-ssa.h b/gcc/gimple-ssa.h index c89071e..39551da 100644 --- a/gcc/gimple-ssa.h +++ b/gcc/gimple-ssa.h @@ -90,6 +90,9 @@ struct GTY(()) gimple_df { /* Free list of SSA_NAMEs. */ vec<tree, va_gc> *free_ssanames; + /* Queue of SSA_NAMEs to be freed at the next opportunity. */ + vec<tree, va_gc> *free_ssanames_queue; + /* Hashtable holding definition for symbol. If this field is not NULL, it means that the first reference to this variable in the function is a USE or a VUSE. In those cases, the SSA renamer creates an SSA name diff --git a/gcc/passes.c b/gcc/passes.c index d06a293..5b41102 100644 --- a/gcc/passes.c +++ b/gcc/passes.c @@ -84,6 +84,7 @@ along with GCC; see the file COPYING3. If not see #include "cfgrtl.h" #include "tree-ssa-live.h" /* For remove_unused_locals. */ #include "tree-cfgcleanup.h" +#include "tree-ssanames.h" using namespace gcc; @@ -1913,6 +1914,14 @@ execute_function_todo (function *fn, void *data) { cleanup_tree_cfg (); + /* Once unreachable nodes have been removed from the CFG, + there can't be any lingering references to released + SSA_NAMES (because there is no more unreachable code). + + Thus, now is the time to flush the SSA_NAMEs freelist. */ + if (fn->gimple_df) + flush_ssaname_freelist (); + /* When cleanup_tree_cfg merges consecutive blocks, it may perform some simplistic propagation when removing single valued PHI nodes. This propagation may, in turn, cause the diff --git a/gcc/tree-ssanames.c b/gcc/tree-ssanames.c index 7235dc3..64e2379 100644 --- a/gcc/tree-ssanames.c +++ b/gcc/tree-ssanames.c @@ -70,6 +70,7 @@ unsigned int ssa_name_nodes_reused; unsigned int ssa_name_nodes_created; #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames +#define FREE_SSANAMES_QUEUE(fun) (fun)->gimple_df->free_ssanames_queue /* Initialize management of SSA_NAMEs to default SIZE. If SIZE is @@ -92,6 +93,7 @@ init_ssanames (struct function *fn, int size) least 50 elements reserved in it. */ SSANAMES (fn)->quick_push (NULL_TREE); FREE_SSANAMES (fn) = NULL; + FREE_SSANAMES_QUEUE (fn) = NULL; fn->gimple_df->ssa_renaming_needed = 0; fn->gimple_df->rename_vops = 0; @@ -104,6 +106,7 @@ fini_ssanames (void) { vec_free (SSANAMES (cfun)); vec_free (FREE_SSANAMES (cfun)); + vec_free (FREE_SSANAMES_QUEUE (cfun)); } /* Dump some simple statistics regarding the re-use of SSA_NAME nodes. */ @@ -115,6 +118,22 @@ ssanames_print_statistics (void) fprintf (stderr, "SSA_NAME nodes reused: %u\n", ssa_name_nodes_reused); } +/* Move all SSA_NAMEs from FREE_SSA_NAMES_QUEUE to FREE_SSA_NAMES. + + We do not, but should have a mode to verify the state of the SSA_NAMEs + lists. In particular at this point every name must be in the IL, + on the free list or in the queue. Anything else is an error. */ + +void +flush_ssaname_freelist (void) +{ + while (!vec_safe_is_empty (FREE_SSANAMES_QUEUE (cfun))) + { + tree t = FREE_SSANAMES_QUEUE (cfun)->pop (); + vec_safe_push (FREE_SSANAMES (cfun), t); + } +} + /* Return an SSA_NAME node for variable VAR defined in statement STMT in function FN. STMT may be an empty statement for artificial references (e.g., default definitions created when a variable is @@ -349,8 +368,8 @@ release_ssa_name_fn (struct function *fn, tree var) /* Note this SSA_NAME is now in the first list. */ SSA_NAME_IN_FREE_LIST (var) = 1; - /* And finally put it on the free list. */ - vec_safe_push (FREE_SSANAMES (fn), var); + /* And finally queue it so that it will be put on the free list. */ + vec_safe_push (FREE_SSANAMES_QUEUE (fn), var); } } @@ -631,6 +650,7 @@ unsigned int pass_release_ssa_names::execute (function *fun) { unsigned i, j; + flush_ssaname_freelist (); int n = vec_safe_length (FREE_SSANAMES (fun)); /* Now release the freelist. */ diff --git a/gcc/tree-ssanames.h b/gcc/tree-ssanames.h index 5688ca5..a915d8f 100644 --- a/gcc/tree-ssanames.h +++ b/gcc/tree-ssanames.h @@ -98,6 +98,7 @@ extern void reset_flow_sensitive_info (tree); extern void reset_flow_sensitive_info_in_bb (basic_block); extern void release_defs (gimple *); extern void replace_ssa_name_symbol (tree, tree); +extern void flush_ssaname_freelist (void); /* Return an SSA_NAME node for variable VAR defined in statement STMT |