};
-static t_bool follow_ssa_edge (class loop *loop, gimple *, gphi *,
- tree *, int);
+static t_bool follow_ssa_edge_expr (class loop *loop, gimple *, tree, gphi *,
+ tree *, int);
/* Follow the ssa edge into the binary expression RHS0 CODE RHS1.
Return true if the strongly connected component has been found. */
(loop->num,
chrec_convert (type, evol, at_stmt),
code, rhs1, at_stmt);
- res = follow_ssa_edge
- (loop, SSA_NAME_DEF_STMT (rhs0), halting_phi, &evol, limit);
+ res = follow_ssa_edge_expr
+ (loop, at_stmt, rhs0, halting_phi, &evol, limit);
if (res == t_true)
*evolution_of_loop = evol;
else if (res == t_false)
(loop->num,
chrec_convert (type, *evolution_of_loop, at_stmt),
code, rhs0, at_stmt);
- res = follow_ssa_edge
- (loop, SSA_NAME_DEF_STMT (rhs1), halting_phi,
+ res = follow_ssa_edge_expr
+ (loop, at_stmt, rhs1, halting_phi,
evolution_of_loop, limit);
if (res == t_true)
;
(loop->num, chrec_convert (type, *evolution_of_loop,
at_stmt),
code, rhs1, at_stmt);
- res = follow_ssa_edge
- (loop, SSA_NAME_DEF_STMT (rhs0), halting_phi,
+ res = follow_ssa_edge_expr
+ (loop, at_stmt, rhs0, halting_phi,
evolution_of_loop, limit);
if (res == t_true)
;
(loop->num, chrec_convert (type, *evolution_of_loop,
at_stmt),
code, rhs0, at_stmt);
- res = follow_ssa_edge
- (loop, SSA_NAME_DEF_STMT (rhs1), halting_phi,
+ res = follow_ssa_edge_expr
+ (loop, at_stmt, rhs1, halting_phi,
evolution_of_loop, limit);
if (res == t_true)
;
*evolution_of_loop = add_to_evolution
(loop->num, chrec_convert (type, *evolution_of_loop, at_stmt),
MINUS_EXPR, rhs1, at_stmt);
- res = follow_ssa_edge (loop, SSA_NAME_DEF_STMT (rhs0), halting_phi,
- evolution_of_loop, limit);
+ res = follow_ssa_edge_expr (loop, at_stmt, rhs0, halting_phi,
+ evolution_of_loop, limit);
if (res == t_true)
;
else if (res == t_dont_know)
return res;
}
-/* Follow the ssa edge into the expression EXPR.
- Return true if the strongly connected component has been found. */
-
-static t_bool
-follow_ssa_edge_expr (class loop *loop, gimple *at_stmt, tree expr,
- gphi *halting_phi, tree *evolution_of_loop,
- int limit)
-{
- enum tree_code code = TREE_CODE (expr);
- tree type = TREE_TYPE (expr), rhs0, rhs1;
- t_bool res;
-
- /* The EXPR is one of the following cases:
- - an SSA_NAME,
- - an INTEGER_CST,
- - a PLUS_EXPR,
- - a POINTER_PLUS_EXPR,
- - a MINUS_EXPR,
- - an ASSERT_EXPR,
- - other cases are not yet handled. */
-
- switch (code)
- {
- CASE_CONVERT:
- /* This assignment is under the form "a_1 = (cast) rhs. */
- res = follow_ssa_edge_expr (loop, at_stmt, TREE_OPERAND (expr, 0),
- halting_phi, evolution_of_loop, limit);
- *evolution_of_loop = chrec_convert (type, *evolution_of_loop, at_stmt);
- break;
-
- case INTEGER_CST:
- /* This assignment is under the form "a_1 = 7". */
- res = t_false;
- break;
-
- case SSA_NAME:
- /* This assignment is under the form: "a_1 = b_2". */
- res = follow_ssa_edge
- (loop, SSA_NAME_DEF_STMT (expr), halting_phi, evolution_of_loop, limit);
- break;
-
- case POINTER_PLUS_EXPR:
- case PLUS_EXPR:
- case MINUS_EXPR:
- /* This case is under the form "rhs0 +- rhs1". */
- rhs0 = TREE_OPERAND (expr, 0);
- rhs1 = TREE_OPERAND (expr, 1);
- type = TREE_TYPE (rhs0);
- STRIP_USELESS_TYPE_CONVERSION (rhs0);
- STRIP_USELESS_TYPE_CONVERSION (rhs1);
- res = follow_ssa_edge_binary (loop, at_stmt, type, rhs0, code, rhs1,
- halting_phi, evolution_of_loop, limit);
- break;
-
- case ADDR_EXPR:
- /* Handle &MEM[ptr + CST] which is equivalent to POINTER_PLUS_EXPR. */
- if (TREE_CODE (TREE_OPERAND (expr, 0)) == MEM_REF)
- {
- expr = TREE_OPERAND (expr, 0);
- rhs0 = TREE_OPERAND (expr, 0);
- rhs1 = TREE_OPERAND (expr, 1);
- type = TREE_TYPE (rhs0);
- STRIP_USELESS_TYPE_CONVERSION (rhs0);
- STRIP_USELESS_TYPE_CONVERSION (rhs1);
- res = follow_ssa_edge_binary (loop, at_stmt, type,
- rhs0, POINTER_PLUS_EXPR, rhs1,
- halting_phi, evolution_of_loop, limit);
- }
- else
- res = t_false;
- break;
-
- case ASSERT_EXPR:
- /* This assignment is of the form: "a_1 = ASSERT_EXPR <a_2, ...>"
- It must be handled as a copy assignment of the form a_1 = a_2. */
- rhs0 = ASSERT_EXPR_VAR (expr);
- if (TREE_CODE (rhs0) == SSA_NAME)
- res = follow_ssa_edge (loop, SSA_NAME_DEF_STMT (rhs0),
- halting_phi, evolution_of_loop, limit);
- else
- res = t_false;
- break;
-
- default:
- res = t_false;
- break;
- }
-
- return res;
-}
-
-/* Follow the ssa edge into the right hand side of an assignment STMT.
- Return true if the strongly connected component has been found. */
-
-static t_bool
-follow_ssa_edge_in_rhs (class loop *loop, gimple *stmt,
- gphi *halting_phi, tree *evolution_of_loop,
- int limit)
-{
- enum tree_code code = gimple_assign_rhs_code (stmt);
- tree type = gimple_expr_type (stmt), rhs1, rhs2;
- t_bool res;
-
- switch (code)
- {
- CASE_CONVERT:
- /* This assignment is under the form "a_1 = (cast) rhs. */
- res = follow_ssa_edge_expr (loop, stmt, gimple_assign_rhs1 (stmt),
- halting_phi, evolution_of_loop, limit);
- *evolution_of_loop = chrec_convert (type, *evolution_of_loop, stmt);
- break;
-
- case POINTER_PLUS_EXPR:
- case PLUS_EXPR:
- case MINUS_EXPR:
- rhs1 = gimple_assign_rhs1 (stmt);
- rhs2 = gimple_assign_rhs2 (stmt);
- type = TREE_TYPE (rhs1);
- res = follow_ssa_edge_binary (loop, stmt, type, rhs1, code, rhs2,
- halting_phi, evolution_of_loop, limit);
- break;
-
- default:
- if (get_gimple_rhs_class (code) == GIMPLE_SINGLE_RHS)
- res = follow_ssa_edge_expr (loop, stmt, gimple_assign_rhs1 (stmt),
- halting_phi, evolution_of_loop, limit);
- else
- res = t_false;
- break;
- }
-
- return res;
-}
-
/* Checks whether the I-th argument of a PHI comes from a backedge. */
static bool
if (TREE_CODE (branch) == SSA_NAME)
{
*evolution_of_branch = init_cond;
- return follow_ssa_edge (loop, SSA_NAME_DEF_STMT (branch), halting_phi,
- evolution_of_branch, limit);
+ return follow_ssa_edge_expr (loop, condition_phi, branch, halting_phi,
+ evolution_of_branch, limit);
}
/* This case occurs when one of the condition branches sets
evolution_of_loop, limit);
}
-/* Follow an SSA edge from a loop-phi-node to itself, constructing a
- path that is analyzed on the return walk. */
+/* Follow the ssa edge into the expression EXPR.
+ Return true if the strongly connected component has been found. */
static t_bool
-follow_ssa_edge (class loop *loop, gimple *def, gphi *halting_phi,
- tree *evolution_of_loop, int limit)
+follow_ssa_edge_expr (class loop *loop, gimple *at_stmt, tree expr,
+ gphi *halting_phi, tree *evolution_of_loop,
+ int limit)
{
- class loop *def_loop;
+ enum tree_code code;
+ tree type, rhs0, rhs1 = NULL_TREE;
- if (gimple_nop_p (def))
- return t_false;
+ /* The EXPR is one of the following cases:
+ - an SSA_NAME,
+ - an INTEGER_CST,
+ - a PLUS_EXPR,
+ - a POINTER_PLUS_EXPR,
+ - a MINUS_EXPR,
+ - an ASSERT_EXPR,
+ - other cases are not yet handled. */
- /* Give up if the path is longer than the MAX that we allow. */
- if (limit > PARAM_VALUE (PARAM_SCEV_MAX_EXPR_COMPLEXITY))
- return t_dont_know;
+ /* For SSA_NAME look at the definition statement, handling
+ PHI nodes and otherwise expand appropriately for the expression
+ handling below. */
+ if (TREE_CODE (expr) == SSA_NAME)
+ {
+ gimple *def = SSA_NAME_DEF_STMT (expr);
- def_loop = loop_containing_stmt (def);
+ if (gimple_nop_p (def))
+ return t_false;
- switch (gimple_code (def))
- {
- case GIMPLE_PHI:
- if (!loop_phi_node_p (def))
- /* DEF is a condition-phi-node. Follow the branches, and
- record their evolutions. Finally, merge the collected
- information and set the approximation to the main
- variable. */
- return follow_ssa_edge_in_condition_phi
- (loop, as_a <gphi *> (def), halting_phi, evolution_of_loop,
- limit);
-
- /* When the analyzed phi is the halting_phi, the
- depth-first search is over: we have found a path from
- the halting_phi to itself in the loop. */
- if (def == halting_phi)
- return t_true;
+ /* Give up if the path is longer than the MAX that we allow. */
+ if (limit > PARAM_VALUE (PARAM_SCEV_MAX_EXPR_COMPLEXITY))
+ return t_dont_know;
- /* Otherwise, the evolution of the HALTING_PHI depends
- on the evolution of another loop-phi-node, i.e. the
- evolution function is a higher degree polynomial. */
- if (def_loop == loop)
+ if (gphi *phi = dyn_cast <gphi *>(def))
+ {
+ if (!loop_phi_node_p (phi))
+ /* DEF is a condition-phi-node. Follow the branches, and
+ record their evolutions. Finally, merge the collected
+ information and set the approximation to the main
+ variable. */
+ return follow_ssa_edge_in_condition_phi
+ (loop, phi, halting_phi, evolution_of_loop, limit);
+
+ /* When the analyzed phi is the halting_phi, the
+ depth-first search is over: we have found a path from
+ the halting_phi to itself in the loop. */
+ if (phi == halting_phi)
+ return t_true;
+
+ /* Otherwise, the evolution of the HALTING_PHI depends
+ on the evolution of another loop-phi-node, i.e. the
+ evolution function is a higher degree polynomial. */
+ class loop *def_loop = loop_containing_stmt (def);
+ if (def_loop == loop)
+ return t_false;
+
+ /* Inner loop. */
+ if (flow_loop_nested_p (loop, def_loop))
+ return follow_ssa_edge_inner_loop_phi
+ (loop, phi, halting_phi, evolution_of_loop,
+ limit + 1);
+
+ /* Outer loop. */
+ return t_false;
+ }
+
+ /* At this level of abstraction, the program is just a set
+ of GIMPLE_ASSIGNs and PHI_NODEs. In principle there is no
+ other def to be handled. */
+ if (!is_gimple_assign (def))
return t_false;
- /* Inner loop. */
- if (flow_loop_nested_p (loop, def_loop))
- return follow_ssa_edge_inner_loop_phi
- (loop, as_a <gphi *> (def), halting_phi, evolution_of_loop,
- limit + 1);
+ code = gimple_assign_rhs_code (def);
+ switch (get_gimple_rhs_class (code))
+ {
+ case GIMPLE_BINARY_RHS:
+ rhs0 = gimple_assign_rhs1 (def);
+ rhs1 = gimple_assign_rhs2 (def);
+ break;
+ case GIMPLE_UNARY_RHS:
+ case GIMPLE_SINGLE_RHS:
+ rhs0 = gimple_assign_rhs1 (def);
+ break;
+ default:
+ return t_false;
+ }
+ type = TREE_TYPE (gimple_assign_lhs (def));
+ at_stmt = def;
+ }
+ else
+ {
+ code = TREE_CODE (expr);
+ type = TREE_TYPE (expr);
+ switch (code)
+ {
+ CASE_CONVERT:
+ rhs0 = TREE_OPERAND (expr, 0);
+ break;
+ case POINTER_PLUS_EXPR:
+ case PLUS_EXPR:
+ case MINUS_EXPR:
+ rhs0 = TREE_OPERAND (expr, 0);
+ rhs1 = TREE_OPERAND (expr, 1);
+ break;
+ default:
+ rhs0 = expr;
+ }
+ }
+
+ switch (code)
+ {
+ CASE_CONVERT:
+ {
+ /* This assignment is under the form "a_1 = (cast) rhs. */
+ t_bool res = follow_ssa_edge_expr (loop, at_stmt, rhs0, halting_phi,
+ evolution_of_loop, limit);
+ *evolution_of_loop = chrec_convert (type, *evolution_of_loop, at_stmt);
+ return res;
+ }
- /* Outer loop. */
+ case INTEGER_CST:
+ /* This assignment is under the form "a_1 = 7". */
return t_false;
- case GIMPLE_ASSIGN:
- return follow_ssa_edge_in_rhs (loop, def, halting_phi,
- evolution_of_loop, limit);
+ case ADDR_EXPR:
+ {
+ /* Handle &MEM[ptr + CST] which is equivalent to POINTER_PLUS_EXPR. */
+ if (TREE_CODE (TREE_OPERAND (rhs0, 0)) != MEM_REF)
+ return t_false;
+ tree mem = TREE_OPERAND (rhs0, 0);
+ rhs0 = TREE_OPERAND (mem, 0);
+ rhs1 = TREE_OPERAND (mem, 1);
+ code = POINTER_PLUS_EXPR;
+ }
+ /* Fallthru. */
+ case POINTER_PLUS_EXPR:
+ case PLUS_EXPR:
+ case MINUS_EXPR:
+ /* This case is under the form "rhs0 +- rhs1". */
+ STRIP_USELESS_TYPE_CONVERSION (rhs0);
+ STRIP_USELESS_TYPE_CONVERSION (rhs1);
+ return follow_ssa_edge_binary (loop, at_stmt, type, rhs0, code, rhs1,
+ halting_phi, evolution_of_loop, limit);
+
+ case ASSERT_EXPR:
+ /* This assignment is of the form: "a_1 = ASSERT_EXPR <a_2, ...>"
+ It must be handled as a copy assignment of the form a_1 = a_2. */
+ return follow_ssa_edge_expr (loop, at_stmt, ASSERT_EXPR_VAR (rhs0),
+ halting_phi, evolution_of_loop, limit);
default:
- /* At this level of abstraction, the program is just a set
- of GIMPLE_ASSIGNs and PHI_NODEs. In principle there is no
- other node to be handled. */
return t_false;
}
}
for (i = 0; i < n; i++)
{
tree arg = PHI_ARG_DEF (loop_phi_node, i);
- gimple *ssa_chain;
tree ev_fn;
t_bool res;
{
bool val = false;
- ssa_chain = SSA_NAME_DEF_STMT (arg);
-
/* Pass in the initial condition to the follow edge function. */
ev_fn = init_cond;
- res = follow_ssa_edge (loop, ssa_chain, loop_phi_node, &ev_fn, 0);
+ res = follow_ssa_edge_expr (loop, loop_phi_node, arg,
+ loop_phi_node, &ev_fn, 0);
/* If ev_fn has no evolution in the inner loop, and the
init_cond is not equal to ev_fn, then we have an
projects / gcc.git / commitdiff