+ /* In the following code
+ for (loop1)
+ if (cond)
+ for (loop2)
+ body;
+ guess that cond is unlikely. */
+ if (loop_outer (loop)->num)
+ {
+ basic_block bb = NULL;
+ edge preheader_edge = loop_preheader_edge (loop);
+
+ if (single_pred_p (preheader_edge->src)
+ && single_succ_p (preheader_edge->src))
+ preheader_edge = single_pred_edge (preheader_edge->src);
+
+ gimple *stmt = last_stmt (preheader_edge->src);
+ /* Pattern match fortran loop preheader:
+ _16 = BUILTIN_EXPECT (_15, 1, PRED_FORTRAN_LOOP_PREHEADER);
+ _17 = (logical(kind=4)) _16;
+ if (_17 != 0)
+ goto <bb 11>;
+ else
+ goto <bb 13>;
+
+ Loop guard branch prediction says nothing about duplicated loop
+ headers produced by fortran frontend and in this case we want
+ to predict paths leading to this preheader. */
+
+ if (stmt
+ && gimple_code (stmt) == GIMPLE_COND
+ && gimple_cond_code (stmt) == NE_EXPR
+ && TREE_CODE (gimple_cond_lhs (stmt)) == SSA_NAME
+ && integer_zerop (gimple_cond_rhs (stmt)))
+ {
+ gimple *call_stmt = SSA_NAME_DEF_STMT (gimple_cond_lhs (stmt));
+ if (gimple_code (call_stmt) == GIMPLE_ASSIGN
+ && gimple_expr_code (call_stmt) == NOP_EXPR
+ && TREE_CODE (gimple_assign_rhs1 (call_stmt)) == SSA_NAME)
+ call_stmt = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (call_stmt));
+ if (gimple_code (call_stmt) == GIMPLE_CALL
+ && gimple_call_internal_p (call_stmt)
+ && gimple_call_internal_fn (call_stmt) == IFN_BUILTIN_EXPECT
+ && TREE_CODE (gimple_call_arg (call_stmt, 2)) == INTEGER_CST
+ && tree_fits_uhwi_p (gimple_call_arg (call_stmt, 2))
+ && tree_to_uhwi (gimple_call_arg (call_stmt, 2))
+ == PRED_FORTRAN_LOOP_PREHEADER)
+ bb = preheader_edge->src;
+ }
+ if (!bb)
+ {
+ if (!dominated_by_p (CDI_DOMINATORS,
+ loop_outer (loop)->latch, loop->header))
+ predict_paths_leading_to_edge (loop_preheader_edge (loop),
+ PRED_LOOP_GUARD,
+ NOT_TAKEN,
+ loop_outer (loop));
+ }
+ else
+ {
+ if (!dominated_by_p (CDI_DOMINATORS,
+ loop_outer (loop)->latch, bb))
+ predict_paths_leading_to (bb,
+ PRED_LOOP_GUARD,
+ NOT_TAKEN,
+ loop_outer (loop));
+ }
+ }
+