The following fixes a goof in if-conversion which did nothing to
false predicated blocks. But we have to at least remove all stores.
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
Richard.
2017-09-22 Richard Biener <rguent...@suse.de>
PR tree-optimization/82291
* tree-if-conv.c (predicate_mem_writes): Make sure to
remove writes in blocks predicated with false.
* gcc.dg/torture/pr82291.c: New testcase.
Index: gcc/tree-if-conv.c
===================================================================
--- gcc/tree-if-conv.c (revision 253090)
+++ gcc/tree-if-conv.c (working copy)
@@ -2197,7 +2197,7 @@ predicate_mem_writes (loop_p loop)
gimple *stmt;
int index;
- if (is_true_predicate (cond) || is_false_predicate (cond))
+ if (is_true_predicate (cond))
continue;
swap = false;
@@ -2210,97 +2210,107 @@ predicate_mem_writes (loop_p loop)
vect_sizes.truncate (0);
vect_masks.truncate (0);
- for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
- if (!gimple_assign_single_p (stmt = gsi_stmt (gsi)))
- continue;
- else if (gimple_plf (stmt, GF_PLF_2))
- {
- tree lhs = gimple_assign_lhs (stmt);
- tree rhs = gimple_assign_rhs1 (stmt);
- tree ref, addr, ptr, mask;
- gcall *new_stmt;
- gimple_seq stmts = NULL;
- int bitsize = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (lhs)));
- ref = TREE_CODE (lhs) == SSA_NAME ? rhs : lhs;
- mark_addressable (ref);
- addr = force_gimple_operand_gsi (&gsi, build_fold_addr_expr (ref),
- true, NULL_TREE, true,
- GSI_SAME_STMT);
- if (!vect_sizes.is_empty ()
- && (index = mask_exists (bitsize, vect_sizes)) != -1)
- /* Use created mask. */
- mask = vect_masks[index];
- else
- {
- if (COMPARISON_CLASS_P (cond))
- mask = gimple_build (&stmts, TREE_CODE (cond),
- boolean_type_node,
- TREE_OPERAND (cond, 0),
- TREE_OPERAND (cond, 1));
- else
- {
- gcc_assert (TREE_CODE (cond) == SSA_NAME);
- mask = cond;
- }
-
- if (swap)
- {
- tree true_val
- = constant_boolean_node (true, TREE_TYPE (mask));
- mask = gimple_build (&stmts, BIT_XOR_EXPR,
- TREE_TYPE (mask), mask, true_val);
- }
- gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT);
-
- mask = ifc_temp_var (TREE_TYPE (mask), mask, &gsi);
- /* Save mask and its size for further use. */
- vect_sizes.safe_push (bitsize);
- vect_masks.safe_push (mask);
- }
- ptr = build_int_cst (reference_alias_ptr_type (ref),
- get_object_alignment (ref));
- /* Copy points-to info if possible. */
- if (TREE_CODE (addr) == SSA_NAME && !SSA_NAME_PTR_INFO (addr))
- copy_ref_info (build2 (MEM_REF, TREE_TYPE (ref), addr, ptr),
- ref);
- if (TREE_CODE (lhs) == SSA_NAME)
- {
- new_stmt
- = gimple_build_call_internal (IFN_MASK_LOAD, 3, addr,
- ptr, mask);
- gimple_call_set_lhs (new_stmt, lhs);
- gimple_set_vuse (new_stmt, gimple_vuse (stmt));
- }
- else
- {
- new_stmt
- = gimple_build_call_internal (IFN_MASK_STORE, 4, addr, ptr,
+ for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
+ {
+ if (!gimple_assign_single_p (stmt = gsi_stmt (gsi)))
+ ;
+ else if (is_false_predicate (cond))
+ {
+ unlink_stmt_vdef (stmt);
+ gsi_remove (&gsi, true);
+ release_defs (stmt);
+ continue;
+ }
+ else if (gimple_plf (stmt, GF_PLF_2))
+ {
+ tree lhs = gimple_assign_lhs (stmt);
+ tree rhs = gimple_assign_rhs1 (stmt);
+ tree ref, addr, ptr, mask;
+ gcall *new_stmt;
+ gimple_seq stmts = NULL;
+ int bitsize = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (lhs)));
+ ref = TREE_CODE (lhs) == SSA_NAME ? rhs : lhs;
+ mark_addressable (ref);
+ addr = force_gimple_operand_gsi (&gsi, build_fold_addr_expr (ref),
+ true, NULL_TREE, true,
+ GSI_SAME_STMT);
+ if (!vect_sizes.is_empty ()
+ && (index = mask_exists (bitsize, vect_sizes)) != -1)
+ /* Use created mask. */
+ mask = vect_masks[index];
+ else
+ {
+ if (COMPARISON_CLASS_P (cond))
+ mask = gimple_build (&stmts, TREE_CODE (cond),
+ boolean_type_node,
+ TREE_OPERAND (cond, 0),
+ TREE_OPERAND (cond, 1));
+ else
+ {
+ gcc_assert (TREE_CODE (cond) == SSA_NAME);
+ mask = cond;
+ }
+
+ if (swap)
+ {
+ tree true_val
+ = constant_boolean_node (true, TREE_TYPE (mask));
+ mask = gimple_build (&stmts, BIT_XOR_EXPR,
+ TREE_TYPE (mask), mask, true_val);
+ }
+ gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT);
+
+ mask = ifc_temp_var (TREE_TYPE (mask), mask, &gsi);
+ /* Save mask and its size for further use. */
+ vect_sizes.safe_push (bitsize);
+ vect_masks.safe_push (mask);
+ }
+ ptr = build_int_cst (reference_alias_ptr_type (ref),
+ get_object_alignment (ref));
+ /* Copy points-to info if possible. */
+ if (TREE_CODE (addr) == SSA_NAME && !SSA_NAME_PTR_INFO (addr))
+ copy_ref_info (build2 (MEM_REF, TREE_TYPE (ref), addr, ptr),
+ ref);
+ if (TREE_CODE (lhs) == SSA_NAME)
+ {
+ new_stmt
+ = gimple_build_call_internal (IFN_MASK_LOAD, 3, addr,
+ ptr, mask);
+ gimple_call_set_lhs (new_stmt, lhs);
+ gimple_set_vuse (new_stmt, gimple_vuse (stmt));
+ }
+ else
+ {
+ new_stmt
+ = gimple_build_call_internal (IFN_MASK_STORE, 4, addr, ptr,
mask, rhs);
- gimple_set_vuse (new_stmt, gimple_vuse (stmt));
- gimple_set_vdef (new_stmt, gimple_vdef (stmt));
- SSA_NAME_DEF_STMT (gimple_vdef (new_stmt)) = new_stmt;
- }
- gimple_call_set_nothrow (new_stmt, true);
-
- gsi_replace (&gsi, new_stmt, true);
- }
- else if (gimple_vdef (stmt))
- {
- tree lhs = gimple_assign_lhs (stmt);
- tree rhs = gimple_assign_rhs1 (stmt);
- tree type = TREE_TYPE (lhs);
-
- lhs = ifc_temp_var (type, unshare_expr (lhs), &gsi);
- rhs = ifc_temp_var (type, unshare_expr (rhs), &gsi);
- if (swap)
- std::swap (lhs, rhs);
- cond = force_gimple_operand_gsi_1 (&gsi, unshare_expr (cond),
- is_gimple_condexpr, NULL_TREE,
- true, GSI_SAME_STMT);
- rhs = fold_build_cond_expr (type, unshare_expr (cond), rhs, lhs);
- gimple_assign_set_rhs1 (stmt, ifc_temp_var (type, rhs, &gsi));
- update_stmt (stmt);
- }
+ gimple_set_vuse (new_stmt, gimple_vuse (stmt));
+ gimple_set_vdef (new_stmt, gimple_vdef (stmt));
+ SSA_NAME_DEF_STMT (gimple_vdef (new_stmt)) = new_stmt;
+ }
+ gimple_call_set_nothrow (new_stmt, true);
+
+ gsi_replace (&gsi, new_stmt, true);
+ }
+ else if (gimple_vdef (stmt))
+ {
+ tree lhs = gimple_assign_lhs (stmt);
+ tree rhs = gimple_assign_rhs1 (stmt);
+ tree type = TREE_TYPE (lhs);
+
+ lhs = ifc_temp_var (type, unshare_expr (lhs), &gsi);
+ rhs = ifc_temp_var (type, unshare_expr (rhs), &gsi);
+ if (swap)
+ std::swap (lhs, rhs);
+ cond = force_gimple_operand_gsi_1 (&gsi, unshare_expr (cond),
+ is_gimple_condexpr, NULL_TREE,
+ true, GSI_SAME_STMT);
+ rhs = fold_build_cond_expr (type, unshare_expr (cond), rhs, lhs);
+ gimple_assign_set_rhs1 (stmt, ifc_temp_var (type, rhs, &gsi));
+ update_stmt (stmt);
+ }
+ gsi_next (&gsi);
+ }
}
}
Index: gcc/testsuite/gcc.dg/torture/pr82291.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/pr82291.c (nonexistent)
+++ gcc/testsuite/gcc.dg/torture/pr82291.c (working copy)
@@ -0,0 +1,37 @@
+/* { dg-do run } */
+
+int a, c, d, *h;
+unsigned b;
+
+int *fn1 ()
+{
+ int *f[3], g = 0;
+ for (; g < 3; g++)
+ f[g] = &a;
+ if (--b > a)
+ {
+ if (a > b)
+ d++;
+ return f[0];
+ }
+}
+
+void fn2 ()
+{
+ for (; c >= 0; --c)
+ {
+ int j[] = { 0, 0, 0, 0, 0 };
+ int *k = fn1 ();
+ if (!k)
+ __builtin_abort ();
+ h = &j[4];
+ }
+}
+
+int main ()
+{
+ fn2 ();
+ if (d != 0)
+ __builtin_abort ();
+ return 0;
+}
