On Thu, 8 Oct 2015, Martin Jambor wrote:
> Hi,
>
> the following fixes PR 67794 by properly remapping SSA_NAMEs which are
> based on PARM_DECLs which are about to be removed as unnecessary. And
> by "properly" I mean also when they are defined by a GIMPL_ASM
> statement. In fact, it switches to using an iterator over definitions
> to make sure it always handles everything... well,except for PHIs
> which are still handled specially because, from a quick glance over
> their source, it seemed to me that the iterator does not support them.
>
> Bootstrapped and tested on x86_64-linux. OK for trunk?
> The issue is most probably latent on a number of old branches, do we
> want to backport the patch to any of them?
>
> Thanks,
>
> Martin
>
>
> 2015-10-08 Martin Jambor <mjam...@suse.cz>
>
> tree-optimization/67794
> * tree-sra.c (replace_removed_params_ssa_names): Do not distinguish
> between types of state,ents but accept original definitions as a
> parameter.
> (ipa_sra_modify_function_body): Use FOR_EACH_SSA_DEF_OPERAND to
> iterate over definitions.
>
> testsuite/
> * gcc.dg/ipa/ipa-sra-10.c: Nw test.
> * gcc.dg/torture/pr67794.c: Likewise.
>
> diff --git a/gcc/testsuite/gcc.dg/ipa/ipa-sra-10.c
> b/gcc/testsuite/gcc.dg/ipa/ipa-sra-10.c
> new file mode 100644
> index 0000000..24b64d1
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/ipa/ipa-sra-10.c
> @@ -0,0 +1,34 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fipa-sra -fdump-tree-eipa_sra-details" } */
> +
> +extern void consume (int);
> +extern int glob, glob1, glob2;
> +extern int get (void);
> +
> +
> +static void __attribute__ ((noinline))
> +foo (int a)
> +{
> + a = glob;
> + consume (a);
> + a = get ();
> + consume (a);
> + __asm__ volatile("" : : ""(a));
> + consume (a);
> +
> + if (glob1)
> + a = glob1;
> + else
> + a = glob2;
> + consume (a);
> +}
> +
> +int
> +bar (int a)
> +{
> + foo (a);
> + glob = a;
> + return 0;
> +}
> +
> +/* { dg-final { scan-tree-dump-times "replacing an SSA name of a removed
> param" 4 "eipa_sra" } } */
> diff --git a/gcc/testsuite/gcc.dg/torture/pr67794.c
> b/gcc/testsuite/gcc.dg/torture/pr67794.c
> new file mode 100644
> index 0000000..5489e56
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/torture/pr67794.c
> @@ -0,0 +1,15 @@
> +/* { dg-do compile } */
> +
> +int *b;
> +static void fn1(int *best, int *dmin) {
> + int a[64];
> + dmin = a;
> + __asm__ volatile("" : "+&r"(dmin) : ""(best));
> +}
> +
> +__attribute__((always_inline)) static inline void fn2(int *best) { fn1(best,
> b); }
> +
> +void fn3(void) {
> + int c[1];
> + fn2(c);
> +}
> diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
> index 4327990..f2a4e72 100644
> --- a/gcc/tree-sra.c
> +++ b/gcc/tree-sra.c
> @@ -4612,61 +4612,45 @@ get_adjustment_for_base (ipa_parm_adjustment_vec
> adjustments, tree base)
> return NULL;
> }
>
> -/* If the statement STMT defines an SSA_NAME of a parameter which is to be
> - removed because its value is not used, replace the SSA_NAME with a one
> - relating to a created VAR_DECL together all of its uses and return true.
> - ADJUSTMENTS is a pointer to an adjustments vector. */
> +/* If OLD_NAME, which is being defined by statement STMT, is an SSA_NAME of a
> + parameter which is to be removed because its value is not used, create a
> new
> + SSA_NAME relating to a replacement VAR_DECL, replace all uses of the
> + original with it and return it. If there is no need to re-map, return
> true.
> + ADJUSTMENTS is a pointer to a vector of IPA-SRA adjustments. */
The docs still say we return a bool
Otherwise the patch looks ok to me. I think we want to backport it
to branche(s) after a while.
Thanks,
Richard.
> -static bool
> -replace_removed_params_ssa_names (gimple *stmt,
> +static tree
> +replace_removed_params_ssa_names (tree old_name, gimple *stmt,
> ipa_parm_adjustment_vec adjustments)
> {
> struct ipa_parm_adjustment *adj;
> - tree lhs, decl, repl, name;
> -
> - if (gimple_code (stmt) == GIMPLE_PHI)
> - lhs = gimple_phi_result (stmt);
> - else if (is_gimple_assign (stmt))
> - lhs = gimple_assign_lhs (stmt);
> - else if (is_gimple_call (stmt))
> - lhs = gimple_call_lhs (stmt);
> - else
> - gcc_unreachable ();
> + tree decl, repl, new_name;
>
> - if (TREE_CODE (lhs) != SSA_NAME)
> - return false;
> + if (TREE_CODE (old_name) != SSA_NAME)
> + return NULL;
>
> - decl = SSA_NAME_VAR (lhs);
> + decl = SSA_NAME_VAR (old_name);
> if (decl == NULL_TREE
> || TREE_CODE (decl) != PARM_DECL)
> - return false;
> + return NULL;
>
> adj = get_adjustment_for_base (adjustments, decl);
> if (!adj)
> - return false;
> + return NULL;
>
> repl = get_replaced_param_substitute (adj);
> - name = make_ssa_name (repl, stmt);
> + new_name = make_ssa_name (repl, stmt);
>
> if (dump_file)
> {
> fprintf (dump_file, "replacing an SSA name of a removed param ");
> - print_generic_expr (dump_file, lhs, 0);
> + print_generic_expr (dump_file, old_name, 0);
> fprintf (dump_file, " with ");
> - print_generic_expr (dump_file, name, 0);
> + print_generic_expr (dump_file, new_name, 0);
> fprintf (dump_file, "\n");
> }
>
> - if (is_gimple_assign (stmt))
> - gimple_assign_set_lhs (stmt, name);
> - else if (is_gimple_call (stmt))
> - gimple_call_set_lhs (stmt, name);
> - else
> - gimple_phi_set_result (as_a <gphi *> (stmt), name);
> -
> - replace_uses_by (lhs, name);
> - release_ssa_name (lhs);
> - return true;
> + replace_uses_by (old_name, new_name);
> + return new_name;
> }
>
> /* If the statement STMT contains any expressions that need to replaced with
> a
> @@ -4745,7 +4729,16 @@ ipa_sra_modify_function_body (ipa_parm_adjustment_vec
> adjustments)
> gimple_stmt_iterator gsi;
>
> for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
> - replace_removed_params_ssa_names (gsi_stmt (gsi), adjustments);
> + {
> + gphi *phi = as_a <gphi *> (gsi_stmt (gsi));
> + tree new_lhs, old_lhs = gimple_phi_result (phi);
> + new_lhs = replace_removed_params_ssa_names (old_lhs, phi,
> adjustments);
> + if (new_lhs)
> + {
> + gimple_phi_set_result (phi, new_lhs);
> + release_ssa_name (old_lhs);
> + }
> + }
>
> gsi = gsi_start_bb (bb);
> while (!gsi_end_p (gsi))
> @@ -4765,7 +4758,6 @@ ipa_sra_modify_function_body (ipa_parm_adjustment_vec
> adjustments)
>
> case GIMPLE_ASSIGN:
> modified |= sra_ipa_modify_assign (stmt, &gsi, adjustments);
> - modified |= replace_removed_params_ssa_names (stmt, adjustments);
> break;
>
> case GIMPLE_CALL:
> @@ -4780,8 +4772,6 @@ ipa_sra_modify_function_body (ipa_parm_adjustment_vec
> adjustments)
> {
> t = gimple_call_lhs_ptr (stmt);
> modified |= ipa_modify_expr (t, false, adjustments);
> - modified |= replace_removed_params_ssa_names (stmt,
> - adjustments);
> }
> break;
>
> @@ -4805,6 +4795,20 @@ ipa_sra_modify_function_body (ipa_parm_adjustment_vec
> adjustments)
> break;
> }
>
> + def_operand_p defp;
> + ssa_op_iter iter;
> + FOR_EACH_SSA_DEF_OPERAND (defp, stmt, iter, SSA_OP_DEF)
> + {
> + tree old_def = DEF_FROM_PTR (defp);
> + if (tree new_def = replace_removed_params_ssa_names (old_def,
> stmt,
> + adjustments))
> + {
> + SET_DEF (defp, new_def);
> + release_ssa_name (old_def);
> + modified = true;
> + }
> + }
> +
> if (modified)
> {
> update_stmt (stmt);
>
>
--
Richard Biener <rguent...@suse.de>
SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB
21284 (AG Nuernberg)
