The CLAST produced by CLooG-ISL contains an assignment and GCC chokes
on it. The exact CLAST contains an assignment followed by an if:
scat_1 = max(0,ceild(T_4-7,8));
if (scat_1 <= min(1,floord(T_4-1,8))) {
S7(scat_1);
}
This is equivalent to a loop that iterates only once, and so CLooG
generates an assignment followed by an if instead of a loop. This is
an important optimization that was improved in ISL, that allows
if-conversion: imagine GCC having to figure out that a loop like the
following actually iterates only once, and can be converted to an if:
for (scat_1 = max(0,ceild(T_4-7,8)); scat_1 <= min(1,floord(T_4-1,8)); scat_1++)
S7(scat_1);
This patch implements the translation of CLAST assignments.
Bootstrapped and tested on amd64-linux.
Sebastian
2011-07-22 Sebastian Pop <sebastian....@amd.com>
PR middle-end/48648
* graphite-clast-to-gimple.c (clast_get_body_of_loop): Handle
CLAST assignments.
(translate_clast): Same.
(translate_clast_assignment): New.
* gcc.dg/graphite/id-pr48648.c: New.
---
gcc/ChangeLog | 8 ++++
gcc/graphite-clast-to-gimple.c | 49 ++++++++++++++++++++++++++++
gcc/testsuite/ChangeLog | 5 +++
gcc/testsuite/gcc.dg/graphite/id-pr48648.c | 21 ++++++++++++
4 files changed, 83 insertions(+), 0 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/graphite/id-pr48648.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9cfa21b..303c9c9 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2011-07-22 Sebastian Pop <sebastian....@amd.com>
+
+ PR middle-end/48648
+ * graphite-clast-to-gimple.c (clast_get_body_of_loop): Handle
+ CLAST assignments.
+ (translate_clast): Same.
+ (translate_clast_assignment): New.
+
2011-07-21 Sebastian Pop <sebastian....@amd.com>
PR middle-end/47654
diff --git a/gcc/graphite-clast-to-gimple.c b/gcc/graphite-clast-to-gimple.c
index ddf6d3d..a4668d3 100644
--- a/gcc/graphite-clast-to-gimple.c
+++ b/gcc/graphite-clast-to-gimple.c
@@ -812,6 +812,9 @@ clast_get_body_of_loop (struct clast_stmt *stmt)
if (CLAST_STMT_IS_A (stmt, stmt_block))
return clast_get_body_of_loop (((struct clast_block *) stmt)->body);
+ if (CLAST_STMT_IS_A (stmt, stmt_ass))
+ return clast_get_body_of_loop (stmt->next);
+
gcc_unreachable ();
}
@@ -1121,6 +1124,48 @@ translate_clast_for (loop_p context_loop, struct
clast_for *stmt, edge next_e,
return last_e;
}
+/* Translates a clast assignment STMT to gimple.
+
+ - NEXT_E is the edge where new generated code should be attached.
+ - BB_PBB_MAPPING is is a basic_block and it's related poly_bb_p mapping. */
+
+static edge
+translate_clast_assignment (struct clast_assignment *stmt, edge next_e,
+ int level, ivs_params_p ip)
+{
+ gimple_seq stmts;
+ mpz_t v1, v2;
+ tree type, new_name, var;
+ edge res = single_succ_edge (split_edge (next_e));
+ struct clast_expr *expr = (struct clast_expr *) stmt->RHS;
+ struct clast_user_stmt *body
+ = clast_get_body_of_loop ((struct clast_stmt *) stmt);
+ poly_bb_p pbb = (poly_bb_p) cloog_statement_usr (body->statement);
+
+ mpz_init (v1);
+ mpz_init (v2);
+ type = type_for_clast_expr (expr, ip, v1, v2);
+ var = create_tmp_var (type, "graphite_var");
+ new_name = force_gimple_operand (clast_to_gcc_expression (type, expr, ip),
+ &stmts, true, var);
+ add_referenced_var (var);
+ if (stmts)
+ {
+ gsi_insert_seq_on_edge (next_e, stmts);
+ gsi_commit_edge_inserts ();
+ }
+
+ compute_bounds_for_level (pbb, level, v1, v2);
+ save_clast_name_index (ip->newivs_index, stmt->LHS,
+ VEC_length (tree, *(ip->newivs)), level, v1, v2);
+ VEC_safe_push (tree, heap, *(ip->newivs), new_name);
+
+ mpz_clear (v1);
+ mpz_clear (v2);
+
+ return res;
+}
+
/* Translates a clast guard statement STMT to gimple.
- NEXT_E is the edge where new generated code should be attached.
@@ -1171,6 +1216,10 @@ translate_clast (loop_p context_loop, struct clast_stmt
*stmt, edge next_e,
else if (CLAST_STMT_IS_A (stmt, stmt_block))
next_e = translate_clast (context_loop, ((struct clast_block *)
stmt)->body,
next_e, bb_pbb_mapping, level, ip);
+
+ else if (CLAST_STMT_IS_A (stmt, stmt_ass))
+ next_e = translate_clast_assignment ((struct clast_assignment *) stmt,
+ next_e, level, ip);
else
gcc_unreachable();
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index a63b647..bfdbcfb 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-07-22 Sebastian Pop <sebastian....@amd.com>
+
+ PR middle-end/48648
+ * gcc.dg/graphite/id-pr48648.c: New.
+
2011-07-21 Sebastian Pop <sebastian....@amd.com>
PR middle-end/47654
diff --git a/gcc/testsuite/gcc.dg/graphite/id-pr48648.c
b/gcc/testsuite/gcc.dg/graphite/id-pr48648.c
new file mode 100644
index 0000000..ff58ec2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/graphite/id-pr48648.c
@@ -0,0 +1,21 @@
+/* { dg-options "-O -fgraphite-identity" } */
+
+void *foo(const void *a);
+
+void bug48648()
+{
+ unsigned char a[2];
+ long b;
+ int i;
+
+ for(i = 0; i < 2; i++) {
+ if (b <= 0)
+ a[i] = 0;
+ else if (b >= 8)
+ a[i] = 0;
+ else
+ a[i] = 0;
+ b -= 8;
+ }
+ foo(&a);
+}
--
1.7.4.1
