On Fri, 10 Feb 2012, Richard Guenther wrote:
>
> I've played with
>
> Index: tree-ssa.c
> ===================================================================
> --- tree-ssa.c (revision 184088)
> +++ tree-ssa.c (working copy)
> @@ -944,6 +944,11 @@ verify_ssa (bool check_modified_stmt)
> if (!gimple_nop_p (stmt))
> {
> basic_block bb = gimple_bb (stmt);
> + if (!bb)
> + {
> + error ("Unreleased SSA name");
> + goto err;
> + }
> verify_def (bb, definition_block,
> name, stmt, !is_gimple_reg (name));
>
> and noticed we do not properly free a lot of virtual SSA names, leaking
> both SSA names, stmts and operands they point to over time.
>
> The following patch cures the cases I hit with running the tree-ssa.exp
> testsuite. More issues exist, and I guess we should make a more
> verbose variant of the above the default in 4.8 to catch these issues
> (there is a slight issue with this when verify_ssa is invoked during
> loop transforms and the vectorizer has pattern stmts built that are
> not in a basic block ... so maybe we should put the above into some
> other verifier).
>
> Bootstrapped on x86_64-unknown-linux-gnu, testing in currently in
> progress.
>
> I'll commit this unless somebody thinks it's a really bad idea
> at this point (I do not have numbers for the amount of memory
> we save - once we have fully compiled a function and we do not
> need its body for further inlining we throw it away and with it
> all leaked SSA names).
I'm not installing this now because I hit PR52198 with this change.
I'm instead queuing it for 4.8 where I can XFAIL the testcases
that are affected.
Richard.
> 2012-02-10 Richard Guenther <[email protected]>
>
> * tree-nrv.c (tree_nrv): Release VDEFs.
> * tree-inline.c (expand_call_inline): Likewise.
> * tree-sra.c (sra_modify_constructor_assign): Likewise.
> (sra_modify_assign): Likewise.
> * tree-vect-stmts.c (vect_remove_stores): Likewise.
> * tree-vect-loop.c (vect_transform_loop): Likewise.
> * tree-ssa-dom.c (optimize_stmt): Likewise.
> * tree-vect-slp.c (vect_schedule_slp): Likewise.
> * tree-ssa-math-opts.c (execute_cse_sincos): Likewise.
>
> Index: gcc/tree-nrv.c
> ===================================================================
> --- gcc/tree-nrv.c (revision 184088)
> +++ gcc/tree-nrv.c (working copy)
> @@ -244,6 +244,7 @@ tree_nrv (void)
> {
> unlink_stmt_vdef (stmt);
> gsi_remove (&gsi, true);
> + release_defs (stmt);
> }
> else
> {
> Index: gcc/tree-inline.c
> ===================================================================
> --- gcc/tree-inline.c (revision 184088)
> +++ gcc/tree-inline.c (working copy)
> @@ -4002,6 +4002,9 @@ expand_call_inline (basic_block bb, gimp
>
> /* Unlink the calls virtual operands before replacing it. */
> unlink_stmt_vdef (stmt);
> + if (gimple_vdef (stmt)
> + && TREE_CODE (gimple_vdef (stmt)) == SSA_NAME)
> + release_ssa_name (gimple_vdef (stmt));
>
> /* If the inlined function returns a result that we care about,
> substitute the GIMPLE_CALL with an assignment of the return
> @@ -4043,7 +4046,7 @@ expand_call_inline (basic_block bb, gimp
> }
> }
> else
> - gsi_remove (&stmt_gsi, true);
> + gsi_remove (&stmt_gsi, true);
> }
>
> if (purge_dead_abnormal_edges)
> Index: gcc/tree-sra.c
> ===================================================================
> --- gcc/tree-sra.c (revision 184088)
> +++ gcc/tree-sra.c (working copy)
> @@ -2858,6 +2858,7 @@ sra_modify_constructor_assign (gimple *s
> {
> unlink_stmt_vdef (*stmt);
> gsi_remove (gsi, true);
> + release_defs (*stmt);
> return SRA_AM_REMOVED;
> }
> else
> @@ -2881,6 +2882,7 @@ sra_modify_constructor_assign (gimple *s
> init_subtree_with_zero (acc, gsi, false, loc);
> unlink_stmt_vdef (*stmt);
> gsi_remove (gsi, true);
> + release_defs (*stmt);
> return SRA_AM_REMOVED;
> }
> else
> @@ -3125,6 +3127,7 @@ sra_modify_assign (gimple *stmt, gimple_
> gsi_next (gsi);
> unlink_stmt_vdef (*stmt);
> gsi_remove (&orig_gsi, true);
> + release_defs (*stmt);
> sra_stats.deleted++;
> return SRA_AM_REMOVED;
> }
> @@ -3145,6 +3148,7 @@ sra_modify_assign (gimple *stmt, gimple_
> gcc_assert (*stmt == gsi_stmt (*gsi));
> unlink_stmt_vdef (*stmt);
> gsi_remove (gsi, true);
> + release_defs (*stmt);
> sra_stats.deleted++;
> return SRA_AM_REMOVED;
> }
> Index: gcc/tree-vect-stmts.c
> ===================================================================
> --- gcc/tree-vect-stmts.c (revision 184088)
> +++ gcc/tree-vect-stmts.c (working copy)
> @@ -5596,7 +5596,9 @@ vect_remove_stores (gimple first_stmt)
> next = STMT_VINFO_RELATED_STMT (stmt_info);
> /* Free the attached stmt_vec_info and remove the stmt. */
> next_si = gsi_for_stmt (next);
> + unlink_stmt_vdef (next);
> gsi_remove (&next_si, true);
> + release_defs (next);
> free_stmt_vec_info (next);
> next = tmp;
> }
> Index: gcc/tree-vect-loop.c
> ===================================================================
> --- gcc/tree-vect-loop.c (revision 184088)
> +++ gcc/tree-vect-loop.c (working copy)
> @@ -5428,8 +5428,11 @@ vect_transform_loop (loop_vec_info loop_
> else
> {
> /* Free the attached stmt_vec_info and remove the stmt. */
> - free_stmt_vec_info (gsi_stmt (si));
> + gcc_assert (stmt == gsi_stmt (si));
> + free_stmt_vec_info (stmt);
> + unlink_stmt_vdef (stmt);
> gsi_remove (&si, true);
> + release_defs (stmt);
> continue;
> }
> }
> Index: gcc/tree-ssa-dom.c
> ===================================================================
> --- gcc/tree-ssa-dom.c (revision 184088)
> +++ gcc/tree-ssa-dom.c (working copy)
> @@ -2294,6 +2294,7 @@ optimize_stmt (basic_block bb, gimple_st
> int lp_nr = lookup_stmt_eh_lp (stmt);
> unlink_stmt_vdef (stmt);
> gsi_remove (&si, true);
> + release_defs (stmt);
> if (lp_nr != 0)
> {
> bitmap_set_bit (need_eh_cleanup, bb->index);
> Index: gcc/tree-vect-slp.c
> ===================================================================
> --- gcc/tree-vect-slp.c (revision 184088)
> +++ gcc/tree-vect-slp.c (working copy)
> @@ -3008,7 +3008,9 @@ vect_schedule_slp (loop_vec_info loop_vi
> store = STMT_VINFO_RELATED_STMT (vinfo_for_stmt (store));
> /* Free the attached stmt_vec_info and remove the stmt. */
> gsi = gsi_for_stmt (store);
> + unlink_stmt_vdef (store);
> gsi_remove (&gsi, true);
> + release_defs (store);
> free_stmt_vec_info (store);
> }
> }
> Index: gcc/tree-ssa-math-opts.c
> ===================================================================
> --- gcc/tree-ssa-math-opts.c (revision 184088)
> +++ gcc/tree-ssa-math-opts.c (working copy)
> @@ -1430,6 +1430,8 @@ execute_cse_sincos (void)
> gimple_set_location (new_stmt, loc);
> unlink_stmt_vdef (stmt);
> gsi_replace (&gsi, new_stmt, true);
> + if (gimple_vdef (stmt))
> + release_ssa_name (gimple_vdef (stmt));
> }
> break;
>
> @@ -1450,6 +1452,8 @@ execute_cse_sincos (void)
> gimple_set_location (new_stmt, loc);
> unlink_stmt_vdef (stmt);
> gsi_replace (&gsi, new_stmt, true);
> + if (gimple_vdef (stmt))
> + release_ssa_name (gimple_vdef (stmt));
> }
> break;
>
> @@ -1465,6 +1469,8 @@ execute_cse_sincos (void)
> gimple_set_location (new_stmt, loc);
> unlink_stmt_vdef (stmt);
> gsi_replace (&gsi, new_stmt, true);
> + if (gimple_vdef (stmt))
> + release_ssa_name (gimple_vdef (stmt));
> }
> break;
>
>
--
Richard Guenther <[email protected]>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer
