{
/* See above. */
enum pure_const_state_e pure_const_state;
+ /* What user set here; we can be always sure about this. */
+ enum pure_const_state_e state_set_in_source;
/* True if the function could possibly infinite loop. There are a
lot of ways that this could be determined. We are pretty
a behavioral change. */
bool looping;
- /* If the state of the function was set in the source, then assume
- that it was done properly even if the analysis we do would be
- more pessimestic. */
- bool state_set_in_source;
+ bool can_throw;
};
typedef struct funct_state_d * funct_state;
check_decl (funct_state local,
tree t, bool checking_write)
{
- /* If the variable has the "used" attribute, treat it as if it had a
- been touched by the devil. */
- if (lookup_attribute ("used", DECL_ATTRIBUTES (t)))
- {
- local->pure_const_state = IPA_NEITHER;
- local->looping = false;
- return;
- }
-
+ if (MTAG_P (t))
+ return;
/* Do not want to do anything with volatile except mark any
function that uses one to be not const or pure. */
if (TREE_THIS_VOLATILE (t))
{
local->pure_const_state = IPA_NEITHER;
- local->looping = false;
+ if (dump_file)
+ fprintf (dump_file, " Volatile operand is not const/pure");
return;
}
if (!TREE_STATIC (t) && !DECL_EXTERNAL (t))
return;
+ /* If the variable has the "used" attribute, treat it as if it had a
+ been touched by the devil. */
+ if (lookup_attribute ("used", DECL_ATTRIBUTES (t)))
+ {
+ local->pure_const_state = IPA_NEITHER;
+ if (dump_file)
+ fprintf (dump_file, " Used static/global variable is not const/pure\n");
+ return;
+ }
+
/* Since we have dealt with the locals and params cases above, if we
are CHECKING_WRITE, this cannot be a pure or constant
function. */
if (checking_write)
{
local->pure_const_state = IPA_NEITHER;
- local->looping = false;
+ if (dump_file)
+ fprintf (dump_file, " static/global memory write is not const/pure\n");
return;
}
if (DECL_EXTERNAL (t) || TREE_PUBLIC (t))
{
- /* If the front end set the variable to be READONLY and
- constant, we can allow this variable in pure or const
- functions but the scope is too large for our analysis to set
- these bits ourselves. */
-
- if (TREE_READONLY (t)
- && DECL_INITIAL (t)
- && is_gimple_min_invariant (DECL_INITIAL (t)))
- ; /* Read of a constant, do not change the function state. */
+ /* Readonly reads are safe. */
+ if (TREE_READONLY (t) && !TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (t)))
+ return; /* Read of a constant, do not change the function state. */
else
{
+ if (dump_file)
+ fprintf (dump_file, " global memory read is not const\n");
/* Just a regular read. */
if (local->pure_const_state == IPA_CONST)
local->pure_const_state = IPA_PURE;
}
}
-
- /* Compilation level statics can be read if they are readonly
- variables. */
- if (TREE_READONLY (t))
- return;
-
- /* Just a regular read. */
- if (local->pure_const_state == IPA_CONST)
- local->pure_const_state = IPA_PURE;
+ else
+ {
+ /* Compilation level statics can be read if they are readonly
+ variables. */
+ if (TREE_READONLY (t))
+ return;
+
+ if (dump_file)
+ fprintf (dump_file, " static memory read is not const\n");
+ /* Just a regular read. */
+ if (local->pure_const_state == IPA_CONST)
+ local->pure_const_state = IPA_PURE;
+ }
}
-/* If T is a VAR_DECL check to see if it is an allowed reference. */
-
-static void
-check_operand (funct_state local,
- tree t, bool checking_write)
-{
- if (!t) return;
-
- if (TREE_CODE (t) == VAR_DECL)
- check_decl (local, t, checking_write);
-}
-/* Examine tree T for references. */
+/* Check to see if the use (or definition when CHECKING_WRITE is true)
+ variable T is legal in a function that is either pure or const. */
-static void
-check_tree (funct_state local, tree t, bool checking_write)
+static inline void
+check_op (funct_state local,
+ tree t, bool checking_write)
{
- if ((TREE_CODE (t) == EXC_PTR_EXPR) || (TREE_CODE (t) == FILTER_EXPR)
- || TREE_CODE (t) == SSA_NAME)
+ while (t && handled_component_p (t))
+ t = TREE_OPERAND (t, 0);
+ if (!t)
return;
-
- /* Any tree which is volatile disqualifies this function from being
- const or pure. */
- if (TREE_THIS_VOLATILE (t))
- {
- local->pure_const_state = IPA_NEITHER;
- local->looping = false;
- return;
- }
-
- while (TREE_CODE (t) == REALPART_EXPR
- || TREE_CODE (t) == IMAGPART_EXPR
- || handled_component_p (t))
- {
- if (TREE_CODE (t) == ARRAY_REF)
- check_operand (local, TREE_OPERAND (t, 1), false);
- t = TREE_OPERAND (t, 0);
- }
-
- /* The bottom of an indirect reference can only be read, not
- written. */
- if (INDIRECT_REF_P (t))
+ if (INDIRECT_REF_P (t) || TREE_CODE (t) == TARGET_MEM_REF)
{
- check_tree (local, TREE_OPERAND (t, 0), false);
-
- /* Any indirect reference that occurs on the lhs
- disqualifies the function from being pure or const. Any
- indirect reference that occurs on the rhs disqualifies the
- function from being const. */
- if (checking_write)
- {
+ if (TREE_THIS_VOLATILE (t))
+ {
local->pure_const_state = IPA_NEITHER;
- local->looping = false;
+ if (dump_file)
+ fprintf (dump_file, " Volatile indirect ref is not const/pure\n");
return;
}
- else if (local->pure_const_state == IPA_CONST)
- local->pure_const_state = IPA_PURE;
- }
-
- if (SSA_VAR_P (t))
- check_operand (local, t, checking_write);
-}
-
-/* Scan tree T to see if there are any addresses taken in within T. */
-
-static void
-look_for_address_of (funct_state local, tree t)
-{
- if (TREE_CODE (t) == ADDR_EXPR)
- {
- tree x = get_base_var (t);
- if (TREE_CODE (x) == VAR_DECL)
- {
- check_decl (local, x, false);
-
- /* Taking the address of something appears to be reasonable
- in PURE code. Not allowed in const. */
- if (local->pure_const_state == IPA_CONST)
+ else if (checking_write)
+ {
+ local->pure_const_state = IPA_NEITHER;
+ if (dump_file)
+ fprintf (dump_file, " Indirect ref write is not const/pure\n");
+ return;
+ }
+ else
+ {
+ if (dump_file)
+ fprintf (dump_file, " Indirect ref read is not const\n");
+ if (local->pure_const_state == IPA_CONST)
local->pure_const_state = IPA_PURE;
}
}
}
-/* Check to see if T is a read or address of operation on a var we are
- interested in analyzing. LOCAL is passed in to get access to its
- bit vectors. */
-
-static void
-check_rhs_var (funct_state local, tree t)
-{
- look_for_address_of (local, t);
-
- /* Memcmp and strlen can both trap and they are declared pure. */
- if (tree_could_trap_p (t)
- && local->pure_const_state == IPA_CONST)
- local->pure_const_state = IPA_PURE;
-
- check_tree(local, t, false);
-}
-
-/* Check to see if T is an assignment to a var we are interested in
- analyzing. LOCAL is passed in to get access to its bit vectors. */
-
-static void
-check_lhs_var (funct_state local, tree t)
-{
- /* Memcmp and strlen can both trap and they are declared pure.
- Which seems to imply that we can apply the same rule here. */
- if (tree_could_trap_p (t)
- && local->pure_const_state == IPA_CONST)
- local->pure_const_state = IPA_PURE;
-
- check_tree(local, t, true);
-}
-
-/* This is a scaled down version of get_asm_expr_operands from
- tree_ssa_operands.c. The version there runs much later and assumes
- that aliasing information is already available. Here we are just
- trying to find if the set of inputs and outputs contain references
- or address of operations to local static variables. STMT is the
- actual asm statement. */
-
-static void
-get_asm_expr_operands (funct_state local, gimple stmt)
-{
- size_t noutputs = gimple_asm_noutputs (stmt);
- const char **oconstraints
- = (const char **) alloca ((noutputs) * sizeof (const char *));
- size_t i;
- tree op;
- const char *constraint;
- bool allows_mem, allows_reg, is_inout;
-
- for (i = 0; i < noutputs; i++)
- {
- op = gimple_asm_output_op (stmt, i);
- oconstraints[i] = constraint
- = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
- parse_output_constraint (&constraint, i, 0, 0,
- &allows_mem, &allows_reg, &is_inout);
-
- check_lhs_var (local, TREE_VALUE (op));
- }
-
- for (i = 0; i < gimple_asm_ninputs (stmt); i++)
- {
- op = gimple_asm_input_op (stmt, i);
- constraint
- = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (op)));
- parse_input_constraint (&constraint, 0, 0, noutputs, 0,
- oconstraints, &allows_mem, &allows_reg);
-
- check_rhs_var (local, TREE_VALUE (op));
- }
-
- for (i = 0; i < gimple_asm_nclobbers (stmt); i++)
- {
- op = gimple_asm_clobber_op (stmt, i);
- if (simple_cst_equal(TREE_VALUE (op), memory_identifier_string) == 1)
- /* Abandon all hope, ye who enter here. */
- local->pure_const_state = IPA_NEITHER;
- }
-
- if (gimple_asm_volatile_p (stmt))
- local->pure_const_state = IPA_NEITHER;
-}
-
/* Check the parameters of a function call to CALL_EXPR to see if
there are any references in the parameters that are not allowed for
pure or const functions. Also check to see if this is either an
the entire call expression. */
static void
-check_call (funct_state local, gimple call)
+check_call (funct_state local, gimple call, bool ipa)
{
int flags = gimple_call_flags (call);
- tree lhs, callee_t = gimple_call_fndecl (call);
+ tree callee_t = gimple_call_fndecl (call);
struct cgraph_node* callee;
enum availability avail = AVAIL_NOT_AVAILABLE;
- size_t i;
-
- lhs = gimple_call_lhs (call);
- if (lhs)
- check_lhs_var (local, lhs);
+ bool possibly_throws = stmt_could_throw_p (call);
+ bool possibly_throws_externally = (possibly_throws
+ && stmt_can_throw_external (call));
- for (i = 0; i < gimple_call_num_args (call); i++)
- check_rhs_var (local, gimple_call_arg (call, i));
+ if (possibly_throws)
+ {
+ unsigned int i;
+ for (i = 0; i < gimple_num_ops (call); i++)
+ if (gimple_op (call, i)
+ && tree_could_throw_p (gimple_op (call, i)))
+ {
+ if (possibly_throws && flag_non_call_exceptions)
+ {
+ if (dump_file)
+ fprintf (dump_file, " operand can throw; looping\n");
+ local->looping = true;
+ }
+ if (possibly_throws_externally)
+ {
+ if (dump_file)
+ fprintf (dump_file, " operand can throw externally\n");
+ local->can_throw = true;
+ }
+ }
+ }
/* The const and pure flags are set by a variety of places in the
compiler (including here). If someone has already set the flags
or pure. */
if (setjmp_call_p (callee_t))
{
+ if (dump_file)
+ fprintf (dump_file, " setjmp is not const/pure\n");
+ local->looping = true;
local->pure_const_state = IPA_NEITHER;
- local->looping = false;
}
if (DECL_BUILT_IN_CLASS (callee_t) == BUILT_IN_NORMAL)
{
case BUILT_IN_LONGJMP:
case BUILT_IN_NONLOCAL_GOTO:
+ if (dump_file)
+ fprintf (dump_file, " longjmp and nonlocal goto is not const/pure\n");
local->pure_const_state = IPA_NEITHER;
- local->looping = false;
+ local->looping = true;
break;
default:
break;
}
}
+ /* When not in IPA mode, we can still handle self recursion. */
+ if (!ipa && callee_t == current_function_decl)
+ local->looping = true;
/* The callee is either unknown (indirect call) or there is just no
scannable code for it (external call) . We look to see if there
are any bits available for the callee (such as by declaration or
because it is builtin) and process solely on the basis of those
bits. */
- if (avail == AVAIL_NOT_AVAILABLE || avail == AVAIL_OVERWRITABLE)
+ else if (avail <= AVAIL_OVERWRITABLE || !ipa)
{
- if (flags & ECF_PURE)
+ if (possibly_throws && flag_non_call_exceptions)
+ {
+ if (dump_file)
+ fprintf (dump_file, " can throw; looping\n");
+ local->looping = true;
+ }
+ if (possibly_throws_externally)
+ {
+ if (dump_file)
+ {
+ fprintf (dump_file, " can throw externally in region %i\n",
+ lookup_stmt_eh_region (call));
+ if (callee_t)
+ fprintf (dump_file, " callee:%s\n",
+ IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (callee_t)));
+ }
+ local->can_throw = true;
+ }
+ if (flags & ECF_CONST)
{
+ if (callee_t && DECL_LOOPING_CONST_OR_PURE_P (callee_t))
+ local->looping = true;
+ }
+ else if (flags & ECF_PURE)
+ {
+ if (callee_t && DECL_LOOPING_CONST_OR_PURE_P (callee_t))
+ local->looping = true;
+ if (dump_file)
+ fprintf (dump_file, " pure function call in not const\n");
if (local->pure_const_state == IPA_CONST)
local->pure_const_state = IPA_PURE;
}
else
- local->pure_const_state = IPA_NEITHER;
- }
- else
- {
- /* We have the code and we will scan it for the effects. */
- if (flags & ECF_PURE)
{
- if (local->pure_const_state == IPA_CONST)
- local->pure_const_state = IPA_PURE;
+ if (dump_file)
+ fprintf (dump_file, " uknown function call is not const/pure\n");
+ local->pure_const_state = IPA_NEITHER;
+ local->looping = true;
}
}
+ /* Direct functions calls are handled by IPA propagation. */
}
-/* TP is the part of the tree currently under the microscope.
- WALK_SUBTREES is part of the walk_tree api but is unused here.
- DATA is cgraph_node of the function being walked. */
-
-/* FIXME: When this is converted to run over SSA form, this code
- should be converted to use the operand scanner. */
-
-static tree
-scan_function_op (tree *tp, int *walk_subtrees, void *data)
+/* Look into pointer pointed to by GSIP and figure out what interesting side effects
+ it have. */
+static void
+check_stmt (gimple_stmt_iterator *gsip, funct_state local, bool ipa)
{
- struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
- struct cgraph_node *fn = (struct cgraph_node *) wi->info;
- tree t = *tp;
- funct_state local = get_function_state (fn);
+ gimple stmt = gsi_stmt (*gsip);
+ unsigned int i = 0;
+ bitmap_iterator bi;
- switch (TREE_CODE (t))
+ if (dump_file)
{
- case VAR_DECL:
- if (DECL_INITIAL (t))
- walk_tree (&DECL_INITIAL (t), scan_function_op, data, visited_nodes);
- *walk_subtrees = 0;
- break;
-
- case ADDR_EXPR:
- /* This case is here to find addresses on rhs of constructors in
- decl_initial of static variables. */
- check_rhs_var (local, t);
- *walk_subtrees = 0;
- break;
-
- default:
- break;
+ fprintf (dump_file, " scanning: ");
+ print_gimple_stmt (dump_file, stmt, 0, 0);
+ }
+ if (gimple_loaded_syms (stmt))
+ EXECUTE_IF_SET_IN_BITMAP (gimple_loaded_syms (stmt), 0, i, bi)
+ check_decl (local, referenced_var_lookup (i), false);
+ if (gimple_stored_syms (stmt))
+ EXECUTE_IF_SET_IN_BITMAP (gimple_stored_syms (stmt), 0, i, bi)
+ check_decl (local, referenced_var_lookup (i), true);
+
+ if (gimple_code (stmt) != GIMPLE_CALL
+ && stmt_could_throw_p (stmt))
+ {
+ if (flag_non_call_exceptions)
+ {
+ if (dump_file)
+ fprintf (dump_file, " can throw; looping");
+ local->looping = true;
+ }
+ if (stmt_can_throw_external (stmt))
+ {
+ if (dump_file)
+ fprintf (dump_file, " can throw externally");
+ local->can_throw = true;
+ }
}
- return NULL;
-}
-
-static tree
-scan_function_stmt (gimple_stmt_iterator *gsi_p,
- bool *handled_ops_p,
- struct walk_stmt_info *wi)
-{
- struct cgraph_node *fn = (struct cgraph_node *) wi->info;
- gimple stmt = gsi_stmt (*gsi_p);
- funct_state local = get_function_state (fn);
-
switch (gimple_code (stmt))
{
case GIMPLE_ASSIGN:
- {
- /* First look on the lhs and see what variable is stored to */
- tree lhs = gimple_assign_lhs (stmt);
- tree rhs1 = gimple_assign_rhs1 (stmt);
- tree rhs2 = gimple_assign_rhs2 (stmt);
- enum tree_code code = gimple_assign_rhs_code (stmt);
-
- check_lhs_var (local, lhs);
-
- /* For the purposes of figuring out what the cast affects */
-
- /* Next check the operands on the rhs to see if they are ok. */
- switch (TREE_CODE_CLASS (code))
- {
- case tcc_binary:
- {
- check_rhs_var (local, rhs1);
- check_rhs_var (local, rhs2);
- }
- break;
- case tcc_unary:
- {
- check_rhs_var (local, rhs1);
- }
-
- break;
- case tcc_reference:
- check_rhs_var (local, rhs1);
- break;
- case tcc_declaration:
- check_rhs_var (local, rhs1);
- break;
- case tcc_expression:
- switch (code)
- {
- case ADDR_EXPR:
- check_rhs_var (local, rhs1);
- break;
- default:
- break;
- }
- break;
- default:
- break;
- }
- *handled_ops_p = true;
- }
+ check_op (local, gimple_assign_lhs (stmt), true);
+ i = 1;
+ break;
+ case GIMPLE_CALL:
+ check_op (local, gimple_call_lhs (stmt), true);
+ i = 1;
+ check_call (local, stmt, ipa);
break;
-
case GIMPLE_LABEL:
if (DECL_NONLOCAL (gimple_label_label (stmt)))
/* Target of long jump. */
{
+ if (dump_file)
+ fprintf (dump_file, " nonlocal label is not const/pure");
local->pure_const_state = IPA_NEITHER;
- local->looping = false;
}
break;
-
- case GIMPLE_CALL:
- check_call (local, stmt);
- *handled_ops_p = true;
- break;
-
case GIMPLE_ASM:
- get_asm_expr_operands (local, stmt);
- *handled_ops_p = true;
- break;
-
+ for (i = 0; i < gimple_asm_noutputs (stmt); i++)
+ check_op (local, TREE_VALUE (gimple_asm_output_op (stmt, i)), true);
+ for (i = 0; i < gimple_asm_ninputs (stmt); i++)
+ check_op (local, TREE_VALUE (gimple_asm_input_op (stmt, i)), false);
+ for (i = 0; i < gimple_asm_nclobbers (stmt); i++)
+ {
+ tree op = gimple_asm_clobber_op (stmt, i);
+ if (simple_cst_equal(TREE_VALUE (op), memory_identifier_string) == 1)
+ {
+ if (dump_file)
+ fprintf (dump_file, " memory asm clobber is not const/pure");
+ /* Abandon all hope, ye who enter here. */
+ local->pure_const_state = IPA_NEITHER;
+ }
+ }
+ if (gimple_asm_volatile_p (stmt))
+ {
+ if (dump_file)
+ fprintf (dump_file, " volatile is not const/pure");
+ /* Abandon all hope, ye who enter here. */
+ local->pure_const_state = IPA_NEITHER;
+ local->looping = true;
+ }
+ return;
default:
break;
}
- return NULL;
+
+ for (; i < gimple_num_ops (stmt); i++)
+ check_op (local, gimple_op (stmt, i), false);
}
/* This is the main routine for finding the reference patterns for
global variables within a function FN. */
-static void
-analyze_function (struct cgraph_node *fn)
+static funct_state
+analyze_function (struct cgraph_node *fn, bool ipa)
{
tree decl = fn->decl;
- funct_state l = XCNEW (struct funct_state_d);
-
- if (cgraph_function_body_availability (fn) <= AVAIL_OVERWRITABLE)
- return;
-
- set_function_state (fn, l);
-
- l->pure_const_state = IPA_CONST;
- l->state_set_in_source = false;
- if (DECL_LOOPING_CONST_OR_PURE_P (decl))
- l->looping = true;
- else
- l->looping = false;
+ tree old_decl = current_function_decl;
+ funct_state l;
+ basic_block this_block;
- /* If this function does not return normally or does not bind local,
- do not touch this unless it has been marked as const or pure by the
- front end. */
- if (TREE_THIS_VOLATILE (decl)
- || !targetm.binds_local_p (decl))
+ if (cgraph_function_body_availability (fn) <= AVAIL_OVERWRITABLE)
{
- l->pure_const_state = IPA_NEITHER;
- return;
+ if (dump_file)
+ fprintf (dump_file, "Function is not available or overwrittable; not analyzing.\n");
+ return NULL;
}
- if (TREE_READONLY (decl))
- {
- l->pure_const_state = IPA_CONST;
- l->state_set_in_source = true;
- }
- if (DECL_PURE_P (decl))
- {
- l->pure_const_state = IPA_PURE;
- l->state_set_in_source = true;
- }
+ l = XCNEW (struct funct_state_d);
+ l->pure_const_state = IPA_CONST;
+ l->state_set_in_source = IPA_NEITHER;
+ l->looping = false;
+ l->can_throw = false;
if (dump_file)
{
- fprintf (dump_file, "\n local analysis of %s with initial value = %d\n ",
- cgraph_node_name (fn),
- l->pure_const_state);
+ fprintf (dump_file, "\n\n local analysis of %s\n ",
+ cgraph_node_name (fn));
}
- if (!l->state_set_in_source)
+ push_cfun (DECL_STRUCT_FUNCTION (decl));
+ current_function_decl = decl;
+
+ FOR_EACH_BB (this_block)
{
- struct function *this_cfun = DECL_STRUCT_FUNCTION (decl);
- basic_block this_block;
-
- FOR_EACH_BB_FN (this_block, this_cfun)
- {
- gimple_stmt_iterator gsi;
- struct walk_stmt_info wi;
-
- memset (&wi, 0, sizeof(wi));
- for (gsi = gsi_start_bb (this_block);
- !gsi_end_p (gsi);
- gsi_next (&gsi))
- {
- wi.info = fn;
- wi.pset = visited_nodes;
- walk_gimple_stmt (&gsi, scan_function_stmt, scan_function_op,
- &wi);
- if (l->pure_const_state == IPA_NEITHER)
- goto end;
- }
- }
+ gimple_stmt_iterator gsi;
+ struct walk_stmt_info wi;
- if (l->pure_const_state != IPA_NEITHER)
+ memset (&wi, 0, sizeof(wi));
+ for (gsi = gsi_start_bb (this_block);
+ !gsi_end_p (gsi);
+ gsi_next (&gsi))
{
- tree old_decl = current_function_decl;
- /* Const functions cannot have back edges (an
- indication of possible infinite loop side
- effect. */
-
- current_function_decl = fn->decl;
-
- /* The C++ front end, has a tendency to some times jerk away
- a function after it has created it. This should have
- been fixed. */
- gcc_assert (DECL_STRUCT_FUNCTION (fn->decl));
-
- push_cfun (DECL_STRUCT_FUNCTION (fn->decl));
-
- if (mark_dfs_back_edges ())
- l->pure_const_state = IPA_NEITHER;
-
- current_function_decl = old_decl;
- pop_cfun ();
+ check_stmt (&gsi, l, ipa);
+ if (l->pure_const_state == IPA_NEITHER && l->looping && l->can_throw)
+ goto end;
}
}
end:
+ if (l->pure_const_state != IPA_NEITHER)
+ {
+ /* Const functions cannot have back edges (an
+ indication of possible infinite loop side
+ effect. */
+ if (mark_dfs_back_edges ())
+ l->looping = true;
+
+ }
+
+ if (TREE_READONLY (decl))
+ {
+ l->pure_const_state = IPA_CONST;
+ l->state_set_in_source = IPA_CONST;
+ if (!DECL_LOOPING_CONST_OR_PURE_P (decl))
+ l->looping = false;
+ }
+ if (DECL_PURE_P (decl))
+ {
+ if (l->pure_const_state != IPA_CONST)
+ l->pure_const_state = IPA_PURE;
+ l->state_set_in_source = IPA_PURE;
+ if (!DECL_LOOPING_CONST_OR_PURE_P (decl))
+ l->looping = false;
+ }
+ if (TREE_NOTHROW (decl))
+ l->can_throw = false;
+
+ pop_cfun ();
+ current_function_decl = old_decl;
if (dump_file)
{
- fprintf (dump_file, "after local analysis of %s with initial value = %d\n ",
- cgraph_node_name (fn),
- l->pure_const_state);
+ if (l->looping)
+ fprintf (dump_file, "Function is locally looping.\n");
+ if (l->can_throw)
+ fprintf (dump_file, "Function is locally throwing.\n");
+ if (l->pure_const_state == IPA_CONST)
+ fprintf (dump_file, "Function is locally const.\n");
+ if (l->pure_const_state == IPA_PURE)
+ fprintf (dump_file, "Function is locally pure.\n");
}
+ return l;
}
/* Called when new function is inserted to callgraph late. */
since all we would be interested in are the addressof
operations. */
visited_nodes = pointer_set_create ();
- analyze_function (node);
+ set_function_state (node, analyze_function (node, true));
pointer_set_destroy (visited_nodes);
visited_nodes = NULL;
}
*/
for (node = cgraph_nodes; node; node = node->next)
if (cgraph_function_body_availability (node) > AVAIL_OVERWRITABLE)
- analyze_function (node);
+ set_function_state (node, analyze_function (node, true));
pointer_set_destroy (visited_nodes);
visited_nodes = NULL;
{
enum pure_const_state_e pure_const_state = IPA_CONST;
bool looping = false;
+ bool can_throw = false;
int count = 0;
node = order[i];
w = node;
while (w)
{
+ struct cgraph_edge *e;
funct_state w_l = get_function_state (w);
if (pure_const_state < w_l->pure_const_state)
pure_const_state = w_l->pure_const_state;
+ if (w_l->can_throw)
+ can_throw = true;
if (w_l->looping)
looping = true;
- if (pure_const_state == IPA_NEITHER)
+ if (pure_const_state == IPA_NEITHER
+ && can_throw)
break;
- if (!w_l->state_set_in_source)
+ count++;
+
+ if (count > 1)
+ looping = true;
+
+ for (e = w->callees; e; e = e->next_callee)
{
- struct cgraph_edge *e;
- count++;
+ struct cgraph_node *y = e->callee;
- if (count > 1)
- looping = true;
-
- for (e = w->callees; e; e = e->next_callee)
+ if (cgraph_function_body_availability (y) > AVAIL_OVERWRITABLE)
{
- struct cgraph_node *y = e->callee;
-
- if (cgraph_function_body_availability (y) > AVAIL_OVERWRITABLE)
- {
- funct_state y_l = get_function_state (y);
- if (pure_const_state < y_l->pure_const_state)
- pure_const_state = y_l->pure_const_state;
- if (pure_const_state == IPA_NEITHER)
- break;
- if (y_l->looping)
- looping = true;
- }
+ funct_state y_l = get_function_state (y);
+ if (pure_const_state < y_l->pure_const_state)
+ pure_const_state = y_l->pure_const_state;
+ if (pure_const_state == IPA_NEITHER
+ && can_throw)
+ break;
+ if (y_l->looping)
+ looping = true;
+ if (y_l->can_throw && !TREE_NOTHROW (w->decl)
+ /* FIXME: We should check that the throw can get external.
+ We also should handle only loops formed by can throw external
+ edges. */)
+ can_throw = true;
}
}
w_info = (struct ipa_dfs_info *) w->aux;
while (w)
{
funct_state w_l = get_function_state (w);
+ enum pure_const_state_e this_state = pure_const_state;
+ bool this_looping = looping;
- /* All nodes within a cycle share the same info. */
- if (!w_l->state_set_in_source)
+ if (w_l->state_set_in_source != IPA_NEITHER)
{
- w_l->pure_const_state = pure_const_state;
- w_l->looping = looping;
+ if (this_state > w_l->state_set_in_source)
+ this_state = w_l->state_set_in_source;
+ this_looping = false;
+ }
- switch (pure_const_state)
- {
- case IPA_CONST:
- TREE_READONLY (w->decl) = 1;
- DECL_LOOPING_CONST_OR_PURE_P (w->decl) = looping;
- if (dump_file)
- fprintf (dump_file, "Function found to be %sconst: %s\n",
- looping ? "looping " : "",
- lang_hooks.decl_printable_name(w->decl, 2));
- break;
-
- case IPA_PURE:
- DECL_PURE_P (w->decl) = 1;
- DECL_LOOPING_CONST_OR_PURE_P (w->decl) = looping;
- if (dump_file)
- fprintf (dump_file, "Function found to be %spure: %s\n",
- looping ? "looping " : "",
- lang_hooks.decl_printable_name(w->decl, 2));
- break;
-
- default:
- break;
- }
+ /* All nodes within a cycle share the same info. */
+ w_l->pure_const_state = this_state;
+ w_l->looping = this_looping;
+
+ switch (this_state)
+ {
+ case IPA_CONST:
+ if (!TREE_READONLY (w->decl) && dump_file)
+ fprintf (dump_file, "Function found to be %sconst: %s\n",
+ this_looping ? "looping " : "",
+ cgraph_node_name (w));
+ TREE_READONLY (w->decl) = 1;
+ DECL_LOOPING_CONST_OR_PURE_P (w->decl) = this_looping;
+ break;
+
+ case IPA_PURE:
+ if (!DECL_PURE_P (w->decl) && dump_file)
+ fprintf (dump_file, "Function found to be %spure: %s\n",
+ this_looping ? "looping " : "",
+ cgraph_node_name (w));
+ DECL_PURE_P (w->decl) = 1;
+ DECL_LOOPING_CONST_OR_PURE_P (w->decl) = this_looping;
+ break;
+
+ default:
+ break;
+ }
+ if (!can_throw && !TREE_NOTHROW (w->decl))
+ {
+ /* FIXME: TREE_NOTHROW is not set because passmanager will execute
+ verify_ssa and verify_cfg on every function. Before fixup_cfg is done,
+ those functions are going to have NOTHROW calls in EH regions reulting
+ in ICE. */
+ if (dump_file)
+ fprintf (dump_file, "Function found to be nothrow: %s\n",
+ cgraph_node_name (w));
}
w_info = (struct ipa_dfs_info *) w->aux;
w = w_info->next_cycle;
NULL, /* function_transform */
NULL /* variable_transform */
};
+
+/* Simple local pass for pure const discovery reusing the analysis from
+ ipa_pure_const. This pass is effective when executed together with
+ other optimization passes in early optimization pass queue. */
+
+static unsigned int
+local_pure_const (void)
+{
+ bool changed = false;
+ funct_state l;
+
+ /* Because we do not schedule pass_fixup_cfg over whole program after early optimizations
+ we must not promote functions that are called by already processed functions. */
+
+ if (function_called_by_processed_nodes_p ())
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function called in recursive cycle; ignoring\n");
+ return 0;
+ }
+
+ l = analyze_function (cgraph_node (current_function_decl), false);
+ if (!l)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Function has wrong visibility; ignoring\n");
+ return 0;
+ }
+
+ switch (l->pure_const_state)
+ {
+ case IPA_CONST:
+ if (!TREE_READONLY (current_function_decl))
+ {
+ TREE_READONLY (current_function_decl) = 1;
+ DECL_LOOPING_CONST_OR_PURE_P (current_function_decl) = l->looping;
+ changed = true;
+ if (dump_file)
+ fprintf (dump_file, "Function found to be %sconst: %s\n",
+ l->looping ? "looping " : "",
+ lang_hooks.decl_printable_name (current_function_decl,
+ 2));
+ }
+ else if (DECL_LOOPING_CONST_OR_PURE_P (current_function_decl)
+ && !l->looping)
+ {
+ DECL_LOOPING_CONST_OR_PURE_P (current_function_decl) = false;
+ changed = true;
+ if (dump_file)
+ fprintf (dump_file, "Function found to be non-looping: %s\n",
+ lang_hooks.decl_printable_name (current_function_decl,
+ 2));
+ }
+ break;
+
+ case IPA_PURE:
+ if (!TREE_READONLY (current_function_decl))
+ {
+ DECL_PURE_P (current_function_decl) = 1;
+ DECL_LOOPING_CONST_OR_PURE_P (current_function_decl) = l->looping;
+ changed = true;
+ if (dump_file)
+ fprintf (dump_file, "Function found to be %spure: %s\n",
+ l->looping ? "looping " : "",
+ lang_hooks.decl_printable_name (current_function_decl,
+ 2));
+ }
+ else if (DECL_LOOPING_CONST_OR_PURE_P (current_function_decl)
+ && !l->looping)
+ {
+ DECL_LOOPING_CONST_OR_PURE_P (current_function_decl) = false;
+ changed = true;
+ if (dump_file)
+ fprintf (dump_file, "Function found to be non-looping: %s\n",
+ lang_hooks.decl_printable_name (current_function_decl,
+ 2));
+ }
+ break;
+
+ default:
+ break;
+ }
+ if (!l->can_throw && !TREE_NOTHROW (current_function_decl))
+ {
+ TREE_NOTHROW (current_function_decl) = 1;
+ changed = true;
+ if (dump_file)
+ fprintf (dump_file, "Function found to be nothrow: %s\n",
+ lang_hooks.decl_printable_name (current_function_decl,
+ 2));
+ }
+ if (l)
+ free (l);
+ if (changed)
+ return execute_fixup_cfg ();
+ else
+ return 0;
+}
+
+struct gimple_opt_pass pass_local_pure_const =
+{
+ {
+ GIMPLE_PASS,
+ "local-pure-const", /* name */
+ gate_pure_const, /* gate */
+ local_pure_const, /* execute */
+ NULL, /* sub */
+ NULL, /* next */
+ 0, /* static_pass_number */
+ TV_IPA_PURE_CONST, /* tv_id */
+ 0, /* properties_required */
+ 0, /* properties_provided */
+ 0, /* properties_destroyed */
+ 0, /* todo_flags_start */
+ 0 /* todo_flags_finish */
+ }
+};
projects / platform / upstream / linaro-gcc.git / commitdiff