JDK14/Java14源码在线阅读
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// DFA.CPP - Method definitions for outputting the matcher DFA from ADLC
#include "adlc.hpp"
//---------------------------Switches for debugging output---------------------
static bool debug_output = false;
static bool debug_output1 = false; // top level chain rules
//---------------------------Access to internals of class State----------------
static const char *sLeft = "_kids[0]";
static const char *sRight = "_kids[1]";
//---------------------------DFA productions-----------------------------------
static const char *dfa_production = "DFA_PRODUCTION";
static const char *dfa_production_set_valid = "DFA_PRODUCTION__SET_VALID";
//---------------------------Production State----------------------------------
static const char *knownInvalid = "knownInvalid"; // The result does NOT have a rule defined
static const char *knownValid = "knownValid"; // The result must be produced by a rule
static const char *unknownValid = "unknownValid"; // Unknown (probably due to a child or predicate constraint)
static const char *noConstraint = "noConstraint"; // No constraints seen so far
static const char *hasConstraint = "hasConstraint"; // Within the first constraint
//------------------------------Production------------------------------------
// Track the status of productions for a particular result
class Production {
public:
const char *_result;
const char *_constraint;
const char *_valid;
Expr *_cost_lb; // Cost lower bound for this production
Expr *_cost_ub; // Cost upper bound for this production
public:
Production(const char *result, const char *constraint, const char *valid);
~Production() {};
void initialize(); // reset to be an empty container
const char *valid() const { return _valid; }
Expr *cost_lb() const { return (Expr *)_cost_lb; }
Expr *cost_ub() const { return (Expr *)_cost_ub; }
void print();
};
//------------------------------ProductionState--------------------------------
// Track the status of all production rule results
// Reset for each root opcode (e.g., Op_RegI, Op_AddI, ...)
class ProductionState {
private:
Dict _production; // map result of production, char*, to information or NULL
const char *_constraint;
public:
// cmpstr does string comparisions. hashstr computes a key.
ProductionState(Arena *arena) : _production(cmpstr, hashstr, arena) { initialize(); };
~ProductionState() { };
void initialize(); // reset local and dictionary state
const char *constraint();
void set_constraint(const char *constraint); // currently working inside of constraints
const char *valid(const char *result); // unknownValid, or status for this production
void set_valid(const char *result); // if not constrained, set status to knownValid
Expr *cost_lb(const char *result);
Expr *cost_ub(const char *result);
void set_cost_bounds(const char *result, const Expr *cost, bool has_state_check, bool has_cost_check);
// Return the Production associated with the result,
// or create a new Production and insert it into the dictionary.
Production *getProduction(const char *result);
void print();
private:
// Disable public use of constructor, copy-ctor, ...
ProductionState( ) : _production(cmpstr, hashstr, Form::arena) { assert( false, "NotImplemented"); };
ProductionState( const ProductionState & ) : _production(cmpstr, hashstr, Form::arena) { assert( false, "NotImplemented"); }; // Deep-copy
};
//---------------------------Helper Functions----------------------------------
// cost_check template:
// 1) if (STATE__NOT_YET_VALID(EBXREGI) || _cost[EBXREGI] > c) {
// 2) DFA_PRODUCTION__SET_VALID(EBXREGI, cmovI_memu_rule, c)
// 3) }
//
static void cost_check(FILE *fp, const char *spaces,
const char *arrayIdx, const Expr *cost, const char *rule, ProductionState &status) {
bool state_check = false; // true if this production needs to check validity
bool cost_check = false; // true if this production needs to check cost
bool cost_is_above_upper_bound = false; // true if this production is unnecessary due to high cost
bool cost_is_below_lower_bound = false; // true if this production replaces a higher cost production
// Get information about this production
const Expr *previous_ub = status.cost_ub(arrayIdx);
if( !previous_ub->is_unknown() ) {
if( previous_ub->less_than_or_equal(cost) ) {
cost_is_above_upper_bound = true;
if( debug_output ) { fprintf(fp, "// Previous rule with lower cost than: %s === %s_rule costs %s\n", arrayIdx, rule, cost->as_string()); }
}
}
const Expr *previous_lb = status.cost_lb(arrayIdx);
if( !previous_lb->is_unknown() ) {
if( cost->less_than_or_equal(previous_lb) ) {
cost_is_below_lower_bound = true;
if( debug_output ) { fprintf(fp, "// Previous rule with higher cost\n"); }
}
}
// line 1)
// Check for validity and compare to other match costs
const char *validity_check = status.valid(arrayIdx);
if( validity_check == unknownValid ) {
fprintf(fp, "%sif (STATE__NOT_YET_VALID(%s) || _cost[%s] > %s) {\n", spaces, arrayIdx, arrayIdx, cost->as_string());
state_check = true;
cost_check = true;
}
else if( validity_check == knownInvalid ) {
if( debug_output ) { fprintf(fp, "%s// %s KNOWN_INVALID \n", spaces, arrayIdx); }
}
else if( validity_check == knownValid ) {
if( cost_is_above_upper_bound ) {
// production cost is known to be too high.
return;
} else if( cost_is_below_lower_bound ) {
// production will unconditionally overwrite a previous production that had higher cost
} else {
fprintf(fp, "%sif ( /* %s KNOWN_VALID || */ _cost[%s] > %s) {\n", spaces, arrayIdx, arrayIdx, cost->as_string());
cost_check = true;
}
}
// line 2)
// no need to set State vector if our state is knownValid
const char *production = (validity_check == knownValid) ? dfa_production : dfa_production_set_valid;
fprintf(fp, "%s %s(%s, %s_rule, %s)", spaces, production, arrayIdx, rule, cost->as_string() );
if( validity_check == knownValid ) {
if( cost_is_below_lower_bound ) { fprintf(fp, "\t // overwrites higher cost rule"); }
}
fprintf(fp, "\n");
// line 3)
if( cost_check || state_check ) {
fprintf(fp, "%s}\n", spaces);
}
status.set_cost_bounds(arrayIdx, cost, state_check, cost_check);
// Update ProductionState
if( validity_check != knownValid ) {
// set State vector if not previously known
status.set_valid(arrayIdx);
}
}
//---------------------------child_test----------------------------------------
// Example:
// STATE__VALID_CHILD(_kids[0], FOO) && STATE__VALID_CHILD(_kids[1], BAR)
// Macro equivalent to: _kids[0]->valid(FOO) && _kids[1]->valid(BAR)
//
static void child_test(FILE *fp, MatchList &mList) {
if (mList._lchild) { // If left child, check it
const char* lchild_to_upper = ArchDesc::getMachOperEnum(mList._lchild);
fprintf(fp, "STATE__VALID_CHILD(_kids[0], %s)", lchild_to_upper);
delete[] lchild_to_upper;
}
if (mList._lchild && mList._rchild) { // If both, add the "&&"
fprintf(fp, " && ");
}
if (mList._rchild) { // If right child, check it
const char* rchild_to_upper = ArchDesc::getMachOperEnum(mList._rchild);
fprintf(fp, "STATE__VALID_CHILD(_kids[1], %s)", rchild_to_upper);
delete[] rchild_to_upper;
}
}
//---------------------------calc_cost-----------------------------------------
// Example:
// unsigned int c = _kids[0]->_cost[FOO] + _kids[1]->_cost[BAR] + 5;
//
Expr *ArchDesc::calc_cost(FILE *fp, const char *spaces, MatchList &mList, ProductionState &status) {
fprintf(fp, "%sunsigned int c = ", spaces);
Expr *c = new Expr("0");
if (mList._lchild) { // If left child, add it in
const char* lchild_to_upper = ArchDesc::getMachOperEnum(mList._lchild);
sprintf(Expr::buffer(), "_kids[0]->_cost[%s]", lchild_to_upper);
c->add(Expr::buffer());
delete[] lchild_to_upper;
}
if (mList._rchild) { // If right child, add it in
const char* rchild_to_upper = ArchDesc::getMachOperEnum(mList._rchild);
sprintf(Expr::buffer(), "_kids[1]->_cost[%s]", rchild_to_upper);
c->add(Expr::buffer());
delete[] rchild_to_upper;
}
// Add in cost of this rule
const char *mList_cost = mList.get_cost();
c->add(mList_cost, *this);
fprintf(fp, "%s;\n", c->as_string());
c->set_external_name("c");
return c;
}
//---------------------------gen_match-----------------------------------------
void ArchDesc::gen_match(FILE *fp, MatchList &mList, ProductionState &status, Dict &operands_chained_from) {
const char *spaces4 = " ";
const char *spaces6 = " ";
fprintf(fp, "%s", spaces4);
// Only generate child tests if this is not a leaf node
bool has_child_constraints = mList._lchild || mList._rchild;
const char *predicate_test = mList.get_pred();
if (has_child_constraints || predicate_test) {
// Open the child-and-predicate-test braces
fprintf(fp, "if( ");
status.set_constraint(hasConstraint);
child_test(fp, mList);
// Only generate predicate test if one exists for this match
if (predicate_test) {
if (has_child_constraints) {
fprintf(fp," &&\n");
}
fprintf(fp, "%s %s", spaces6, predicate_test);
}
// End of outer tests
fprintf(fp," ) ");
} else {
// No child or predicate test needed
status.set_constraint(noConstraint);
}
// End of outer tests
fprintf(fp,"{\n");
// Calculate cost of this match
const Expr *cost = calc_cost(fp, spaces6, mList, status);
// Check against other match costs, and update cost & rule vectors
cost_check(fp, spaces6, ArchDesc::getMachOperEnum(mList._resultStr), cost, mList._opcode, status);
// If this is a member of an operand class, update the class cost & rule
expand_opclass( fp, spaces6, cost, mList._resultStr, status);
// Check if this rule should be used to generate the chains as well.
const char *rule = /* set rule to "Invalid" for internal operands */
strcmp(mList._opcode,mList._resultStr) ? mList._opcode : "Invalid";
// If this rule produces an operand which has associated chain rules,
// update the operands with the chain rule + this rule cost & this rule.
chain_rule(fp, spaces6, mList._resultStr, cost, rule, operands_chained_from, status);
// Close the child-and-predicate-test braces
fprintf(fp, " }\n");
}
//---------------------------expand_opclass------------------------------------
// Chain from one result_type to all other members of its operand class
void ArchDesc::expand_opclass(FILE *fp, const char *indent, const Expr *cost,
const char *result_type, ProductionState &status) {
const Form *form = _globalNames[result_type];
OperandForm *op = form ? form->is_operand() : NULL;
if( op && op->_classes.count() > 0 ) {
if( debug_output ) { fprintf(fp, "// expand operand classes for operand: %s \n", (char *)op->_ident ); } // %%%%% Explanation
// Iterate through all operand classes which include this operand
op->_classes.reset();
const char *oclass;
// Expr *cCost = new Expr(cost);
while( (oclass = op->_classes.iter()) != NULL )
// Check against other match costs, and update cost & rule vectors
cost_check(fp, indent, ArchDesc::getMachOperEnum(oclass), cost, result_type, status);
}
}
//---------------------------chain_rule----------------------------------------
// Starting at 'operand', check if we know how to automatically generate other results
void ArchDesc::chain_rule(FILE *fp, const char *indent, const char *operand,
const Expr *icost, const char *irule, Dict &operands_chained_from, ProductionState &status) {
// Check if we have already generated chains from this starting point
if( operands_chained_from[operand] != NULL ) {
return;
} else {
operands_chained_from.Insert( operand, operand);
}
if( debug_output ) { fprintf(fp, "// chain rules starting from: %s and %s \n", (char *)operand, (char *)irule); } // %%%%% Explanation
ChainList *lst = (ChainList *)_chainRules[operand];
if (lst) {
// printf("\nChain from <%s> at cost #%s\n",operand, icost ? icost : "_");
const char *result, *cost, *rule;
for(lst->reset(); (lst->iter(result,cost,rule)) == true; ) {
// Do not generate operands that are already available
if( operands_chained_from[result] != NULL ) {
continue;
} else {
// Compute the cost for previous match + chain_rule_cost
// total_cost = icost + cost;
Expr *total_cost = icost->clone(); // icost + cost
total_cost->add(cost, *this);
// Check for transitive chain rules
Form *form = (Form *)_globalNames[rule];
if ( ! form->is_instruction()) {
// printf(" result=%s cost=%s rule=%s\n", result, total_cost, rule);
// Check against other match costs, and update cost & rule vectors
const char *reduce_rule = strcmp(irule,"Invalid") ? irule : rule;
cost_check(fp, indent, ArchDesc::getMachOperEnum(result), total_cost, reduce_rule, status);
chain_rule(fp, indent, result, total_cost, irule, operands_chained_from, status);
} else {
// printf(" result=%s cost=%s rule=%s\n", result, total_cost, rule);
// Check against other match costs, and update cost & rule vectors
cost_check(fp, indent, ArchDesc::getMachOperEnum(result), total_cost, rule, status);
chain_rule(fp, indent, result, total_cost, rule, operands_chained_from, status);
}
// If this is a member of an operand class, update class cost & rule
expand_opclass( fp, indent, total_cost, result, status );
}
}
}
}
//---------------------------prune_matchlist-----------------------------------
// Check for duplicate entries in a matchlist, and prune out the higher cost
// entry.
void ArchDesc::prune_matchlist(Dict &minimize, MatchList &mlist) {
}
//---------------------------buildDFA------------------------------------------
// DFA is a large switch with case statements for each ideal opcode encountered
// in any match rule in the ad file. Each case has a series of if's to handle
// the match or fail decisions. The matches test the cost function of that
// rule, and prune any cases which are higher cost for the same reduction.
// In order to generate the DFA we walk the table of ideal opcode/MatchList
// pairs generated by the ADLC front end to build the contents of the case
// statements (a series of if statements).
void ArchDesc::buildDFA(FILE* fp) {
int i;
// Remember operands that are the starting points for chain rules.
// Prevent cycles by checking if we have already generated chain.
Dict operands_chained_from(cmpstr, hashstr, Form::arena);
// Hash inputs to match rules so that final DFA contains only one entry for
// each match pattern which is the low cost entry.
Dict minimize(cmpstr, hashstr, Form::arena);
// Track status of dfa for each resulting production
// reset for each ideal root.
ProductionState status(Form::arena);
// Output the start of the DFA method into the output file
fprintf(fp, "\n");
fprintf(fp, "//------------------------- Source -----------------------------------------\n");
// Do not put random source code into the DFA.
// If there are constants which need sharing, put them in "source_hpp" forms.
// _source.output(fp);
fprintf(fp, "\n");
fprintf(fp, "//------------------------- Attributes -------------------------------------\n");
_attributes.output(fp);
fprintf(fp, "\n");
fprintf(fp, "//------------------------- Macros -----------------------------------------\n");
// #define DFA_PRODUCTION(result, rule, cost)\
// _cost[ (result) ] = cost; _rule[ (result) ] = rule;
fprintf(fp, "#define %s(result, rule, cost)\\\n", dfa_production);
fprintf(fp, " _cost[ (result) ] = cost; _rule[ (result) ] = rule;\n");
fprintf(fp, "\n");
// #define DFA_PRODUCTION__SET_VALID(result, rule, cost)\
// DFA_PRODUCTION( (result), (rule), (cost) ); STATE__SET_VALID( (result) );
fprintf(fp, "#define %s(result, rule, cost)\\\n", dfa_production_set_valid);
fprintf(fp, " %s( (result), (rule), (cost) ); STATE__SET_VALID( (result) );\n", dfa_production);
fprintf(fp, "\n");
fprintf(fp, "//------------------------- DFA --------------------------------------------\n");
fprintf(fp,
"// DFA is a large switch with case statements for each ideal opcode encountered\n"
"// in any match rule in the ad file. Each case has a series of if's to handle\n"
"// the match or fail decisions. The matches test the cost function of that\n"
"// rule, and prune any cases which are higher cost for the same reduction.\n"
"// In order to generate the DFA we walk the table of ideal opcode/MatchList\n"
"// pairs generated by the ADLC front end to build the contents of the case\n"
"// statements (a series of if statements).\n"
);
fprintf(fp, "\n");
fprintf(fp, "\n");
if (_dfa_small) {
// Now build the individual routines just like the switch entries in large version
// Iterate over the table of MatchLists, start at first valid opcode of 1
for (i = 1; i < _last_opcode; i++) {
if (_mlistab[i] == NULL) continue;
// Generate the routine header statement for this opcode
fprintf(fp, "void State::_sub_Op_%s(const Node *n){\n", NodeClassNames[i]);
// Generate body. Shared for both inline and out-of-line version
gen_dfa_state_body(fp, minimize, status, operands_chained_from, i);
// End of routine
fprintf(fp, "}\n");
}
}
fprintf(fp, "bool State::DFA");
fprintf(fp, "(int opcode, const Node *n) {\n");
fprintf(fp, " switch(opcode) {\n");
// Iterate over the table of MatchLists, start at first valid opcode of 1
for (i = 1; i < _last_opcode; i++) {
if (_mlistab[i] == NULL) continue;
// Generate the case statement for this opcode
if (_dfa_small) {
fprintf(fp, " case Op_%s: { _sub_Op_%s(n);\n", NodeClassNames[i], NodeClassNames[i]);
} else {
fprintf(fp, " case Op_%s: {\n", NodeClassNames[i]);
// Walk the list, compacting it
gen_dfa_state_body(fp, minimize, status, operands_chained_from, i);
}
// Print the "break"
fprintf(fp, " break;\n");
fprintf(fp, " }\n");
}
// Generate the default case for switch(opcode)
fprintf(fp, " \n");
fprintf(fp, " default:\n");
fprintf(fp, " tty->print(\"Default case invoked for: \\n\");\n");
fprintf(fp, " tty->print(\" opcode = %cd, \\\"%cs\\\"\\n\", opcode, NodeClassNames[opcode]);\n", '%', '%');
fprintf(fp, " return false;\n");
fprintf(fp, " }\n");
// Return status, indicating a successful match.
fprintf(fp, " return true;\n");
// Generate the closing brace for method Matcher::DFA
fprintf(fp, "}\n");
Expr::check_buffers();
}
class dfa_shared_preds {
enum { count = 4 };
static bool _found[count];
static const char* _type [count];
static const char* _var [count];
static const char* _pred [count];
static void check_index(int index) { assert( 0 <= index && index < count, "Invalid index"); }
// Confirm that this is a separate sub-expression.
// Only need to catch common cases like " ... && shared ..."
// and avoid hazardous ones like "...->shared"
static bool valid_loc(char *pred, char *shared) {
// start of predicate is valid
if( shared == pred ) return true;
// Check previous character and recurse if needed
char *prev = shared - 1;
char c = *prev;
switch( c ) {
case ' ':
case '\n':
return dfa_shared_preds::valid_loc(pred, prev);
case '!':
case '(':
case '<':
case '=':
return true;
case '"': // such as: #line 10 "myfile.ad"\n mypredicate
return true;
case '|':
if (prev != pred && *(prev-1) == '|') return true;
break;
case '&':
if (prev != pred && *(prev-1) == '&') return true;
break;
default:
return false;
}
return false;
}
public:
static bool found(int index){ check_index(index); return _found[index]; }
static void set_found(int index, bool val) { check_index(index); _found[index] = val; }
static void reset_found() {
for( int i = 0; i < count; ++i ) { _found[i] = false; }
};
static const char* type(int index) { check_index(index); return _type[index]; }
static const char* var (int index) { check_index(index); return _var [index]; }
static const char* pred(int index) { check_index(index); return _pred[index]; }
// Check each predicate in the MatchList for common sub-expressions
static void cse_matchlist(MatchList *matchList) {
for( MatchList *mList = matchList; mList != NULL; mList = mList->get_next() ) {
Predicate* predicate = mList->get_pred_obj();
char* pred = mList->get_pred();
if( pred != NULL ) {
for(int index = 0; index < count; ++index ) {
const char *shared_pred = dfa_shared_preds::pred(index);
const char *shared_pred_var = dfa_shared_preds::var(index);
bool result = dfa_shared_preds::cse_predicate(predicate, shared_pred, shared_pred_var);
if( result ) dfa_shared_preds::set_found(index, true);
}
}
}
}
// If the Predicate contains a common sub-expression, replace the Predicate's
// string with one that uses the variable name.
static bool cse_predicate(Predicate* predicate, const char *shared_pred, const char *shared_pred_var) {
bool result = false;
char *pred = predicate->_pred;
if( pred != NULL ) {
char *new_pred = pred;
for( char *shared_pred_loc = strstr(new_pred, shared_pred);
shared_pred_loc != NULL && dfa_shared_preds::valid_loc(new_pred,shared_pred_loc);
shared_pred_loc = strstr(new_pred, shared_pred) ) {
// Do not modify the original predicate string, it is shared
if( new_pred == pred ) {
new_pred = strdup(pred);
shared_pred_loc = strstr(new_pred, shared_pred);
}
// Replace shared_pred with variable name
strncpy(shared_pred_loc, shared_pred_var, strlen(shared_pred_var));
}
// Install new predicate
if( new_pred != pred ) {
predicate->_pred = new_pred;
result = true;
}
}
return result;
}
// Output the hoisted common sub-expression if we found it in predicates
static void generate_cse(FILE *fp) {
for(int j = 0; j < count; ++j ) {
if( dfa_shared_preds::found(j) ) {
const char *shared_pred_type = dfa_shared_preds::type(j);
const char *shared_pred_var = dfa_shared_preds::var(j);
const char *shared_pred = dfa_shared_preds::pred(j);
fprintf(fp, " %s %s = %s;\n", shared_pred_type, shared_pred_var, shared_pred);
}
}
}
};
// shared predicates, _var and _pred entry should be the same length
bool dfa_shared_preds::_found[dfa_shared_preds::count]
= { false, false, false, false };
const char* dfa_shared_preds::_type[dfa_shared_preds::count]
= { "int", "jlong", "intptr_t", "bool" };
const char* dfa_shared_preds::_var [dfa_shared_preds::count]
= { "_n_get_int__", "_n_get_long__", "_n_get_intptr_t__", "Compile__current____select_24_bit_instr__" };
const char* dfa_shared_preds::_pred[dfa_shared_preds::count]
= { "n->get_int()", "n->get_long()", "n->get_intptr_t()", "Compile::current()->select_24_bit_instr()" };
void ArchDesc::gen_dfa_state_body(FILE* fp, Dict &minimize, ProductionState &status, Dict &operands_chained_from, int i) {
// Start the body of each Op_XXX sub-dfa with a clean state.
status.initialize();
// Walk the list, compacting it
MatchList* mList = _mlistab[i];
do {
// Hash each entry using inputs as key and pointer as data.
// If there is already an entry, keep the one with lower cost, and
// remove the other one from the list.
prune_matchlist(minimize, *mList);
// Iterate
mList = mList->get_next();
} while(mList != NULL);
// Hoist previously specified common sub-expressions out of predicates
dfa_shared_preds::reset_found();
dfa_shared_preds::cse_matchlist(_mlistab[i]);
dfa_shared_preds::generate_cse(fp);
mList = _mlistab[i];
// Walk the list again, generating code
do {
// Each match can generate its own chains
operands_chained_from.Clear();
gen_match(fp, *mList, status, operands_chained_from);
mList = mList->get_next();
} while(mList != NULL);
// Fill in any chain rules which add instructions
// These can generate their own chains as well.
operands_chained_from.Clear(); //
if( debug_output1 ) { fprintf(fp, "// top level chain rules for: %s \n", (char *)NodeClassNames[i]); } // %%%%% Explanation
const Expr *zeroCost = new Expr("0");
chain_rule(fp, " ", (char *)NodeClassNames[i], zeroCost, "Invalid",
operands_chained_from, status);
}
//------------------------------Expr------------------------------------------
Expr *Expr::_unknown_expr = NULL;
char Expr::string_buffer[STRING_BUFFER_LENGTH];
char Expr::external_buffer[STRING_BUFFER_LENGTH];
bool Expr::_init_buffers = Expr::init_buffers();
Expr::Expr() {
_external_name = NULL;
_expr = "Invalid_Expr";
_min_value = Expr::Max;
_max_value = Expr::Zero;
}
Expr::Expr(const char *cost) {
_external_name = NULL;
int intval = 0;
if( cost == NULL ) {
_expr = "0";
_min_value = Expr::Zero;
_max_value = Expr::Zero;
}
else if( ADLParser::is_int_token(cost, intval) ) {
_expr = cost;
_min_value = intval;
_max_value = intval;
}
else {
assert( strcmp(cost,"0") != 0, "Recognize string zero as an int");
_expr = cost;
_min_value = Expr::Zero;
_max_value = Expr::Max;
}
}
Expr::Expr(const char *name, const char *expression, int min_value, int max_value) {
_external_name = name;
_expr = expression ? expression : name;
_min_value = min_value;
_max_value = max_value;
assert(_min_value >= 0 && _min_value <= Expr::Max, "value out of range");
assert(_max_value >= 0 && _max_value <= Expr::Max, "value out of range");
}
Expr *Expr::clone() const {
Expr *cost = new Expr();
cost->_external_name = _external_name;
cost->_expr = _expr;
cost->_min_value = _min_value;
cost->_max_value = _max_value;
return cost;
}
void Expr::add(const Expr *c) {
// Do not update fields until all computation is complete
const char *external = compute_external(this, c);
const char *expr = compute_expr(this, c);
int min_value = compute_min (this, c);
int max_value = compute_max (this, c);
_external_name = external;
_expr = expr;
_min_value = min_value;
_max_value = max_value;
}
void Expr::add(const char *c) {
Expr *cost = new Expr(c);
add(cost);
}
void Expr::add(const char *c, ArchDesc &AD) {
const Expr *e = AD.globalDefs()[c];
if( e != NULL ) {
// use the value of 'c' defined in <arch>.ad
add(e);
} else {
Expr *cost = new Expr(c);
add(cost);
}
}
const char *Expr::compute_external(const Expr *c1, const Expr *c2) {
const char * result = NULL;
// Preserve use of external name which has a zero value
if( c1->_external_name != NULL ) {
if( c2->is_zero() ) {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s", c1->as_string());
} else {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s+%s", c1->as_string(), c2->as_string());
}
string_buffer[STRING_BUFFER_LENGTH - 1] = '\0';
result = strdup(string_buffer);
}
else if( c2->_external_name != NULL ) {
if( c1->is_zero() ) {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s", c2->_external_name);
} else {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s + %s", c1->as_string(), c2->as_string());
}
string_buffer[STRING_BUFFER_LENGTH - 1] = '\0';
result = strdup(string_buffer);
}
return result;
}
const char *Expr::compute_expr(const Expr *c1, const Expr *c2) {
if( !c1->is_zero() ) {
if( c2->is_zero() ) {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s", c1->_expr);
} else {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s+%s", c1->_expr, c2->_expr);
}
}
else if( !c2->is_zero() ) {
snprintf(string_buffer, STRING_BUFFER_LENGTH, "%s", c2->_expr);
}
else {
sprintf( string_buffer, "0");
}
string_buffer[STRING_BUFFER_LENGTH - 1] = '\0';
char *cost = strdup(string_buffer);
return cost;
}
int Expr::compute_min(const Expr *c1, const Expr *c2) {
int v1 = c1->_min_value;
int v2 = c2->_min_value;
assert(0 <= v2 && v2 <= Expr::Max, "sanity");
assert(v1 <= Expr::Max - v2, "Invalid cost computation");
return v1 + v2;
}
int Expr::compute_max(const Expr *c1, const Expr *c2) {
int v1 = c1->_max_value;
int v2 = c2->_max_value;
// Check for overflow without producing UB. If v2 is positive
// and not larger than Max, the subtraction cannot underflow.
assert(0 <= v2 && v2 <= Expr::Max, "sanity");
if (v1 > Expr::Max - v2) {
return Expr::Max;
}
return v1 + v2;
}
void Expr::print() const {
if( _external_name != NULL ) {
printf(" %s == (%s) === [%d, %d]\n", _external_name, _expr, _min_value, _max_value);
} else {
printf(" %s === [%d, %d]\n", _expr, _min_value, _max_value);
}
}
void Expr::print_define(FILE *fp) const {
assert( _external_name != NULL, "definition does not have a name");
assert( _min_value == _max_value, "Expect user definitions to have constant value");
fprintf(fp, "#define %s (%s) \n", _external_name, _expr);
fprintf(fp, "// value == %d \n", _min_value);
}
void Expr::print_assert(FILE *fp) const {
assert( _external_name != NULL, "definition does not have a name");
assert( _min_value == _max_value, "Expect user definitions to have constant value");
fprintf(fp, " assert( %s == %d, \"Expect (%s) to equal %d\");\n", _external_name, _min_value, _expr, _min_value);
}
Expr *Expr::get_unknown() {
if( Expr::_unknown_expr == NULL ) {
Expr::_unknown_expr = new Expr();
}
return Expr::_unknown_expr;
}
bool Expr::init_buffers() {
// Fill buffers with 0
for( int i = 0; i < STRING_BUFFER_LENGTH; ++i ) {
external_buffer[i] = '\0';
string_buffer[i] = '\0';
}
return true;
}
bool Expr::check_buffers() {
// returns 'true' if buffer use may have overflowed
bool ok = true;
for( int i = STRING_BUFFER_LENGTH - 100; i < STRING_BUFFER_LENGTH; ++i) {
if( external_buffer[i] != '\0' || string_buffer[i] != '\0' ) {
ok = false;
assert( false, "Expr:: Buffer overflow");
}
}
return ok;
}
//------------------------------ExprDict---------------------------------------
// Constructor
ExprDict::ExprDict( CmpKey cmp, Hash hash, Arena *arena )
: _expr(cmp, hash, arena), _defines() {
}
ExprDict::~ExprDict() {
}
// Return # of name-Expr pairs in dict
int ExprDict::Size(void) const {
return _expr.Size();
}
// define inserts the given key-value pair into the dictionary,
// and records the name in order for later output, ...
const Expr *ExprDict::define(const char *name, Expr *expr) {
const Expr *old_expr = (*this)[name];
assert(old_expr == NULL, "Implementation does not support redefinition");
_expr.Insert(name, expr);
_defines.addName(name);
return old_expr;
}
// Insert inserts the given key-value pair into the dictionary. The prior
// value of the key is returned; NULL if the key was not previously defined.
const Expr *ExprDict::Insert(const char *name, Expr *expr) {
return (Expr*)_expr.Insert((void*)name, (void*)expr);
}
// Finds the value of a given key; or NULL if not found.
// The dictionary is NOT changed.
const Expr *ExprDict::operator [](const char *name) const {
return (Expr*)_expr[name];
}
void ExprDict::print_defines(FILE *fp) {
fprintf(fp, "\n");
const char *name = NULL;
for( _defines.reset(); (name = _defines.iter()) != NULL; ) {
const Expr *expr = (const Expr*)_expr[name];
assert( expr != NULL, "name in ExprDict without matching Expr in dictionary");
expr->print_define(fp);
}
}
void ExprDict::print_asserts(FILE *fp) {
fprintf(fp, "\n");
fprintf(fp, " // Following assertions generated from definition section\n");
const char *name = NULL;
for( _defines.reset(); (name = _defines.iter()) != NULL; ) {
const Expr *expr = (const Expr*)_expr[name];
assert( expr != NULL, "name in ExprDict without matching Expr in dictionary");
expr->print_assert(fp);
}
}
// Print out the dictionary contents as key-value pairs
static void dumpekey(const void* key) { fprintf(stdout, "%s", (char*) key); }
static void dumpexpr(const void* expr) { fflush(stdout); ((Expr*)expr)->print(); }
void ExprDict::dump() {
_expr.print(dumpekey, dumpexpr);
}
//------------------------------ExprDict::private------------------------------
// Disable public use of constructor, copy-ctor, operator =, operator ==
ExprDict::ExprDict( ) : _expr(cmpkey,hashkey), _defines() {
assert( false, "NotImplemented");
}
ExprDict::ExprDict( const ExprDict & ) : _expr(cmpkey,hashkey), _defines() {
assert( false, "NotImplemented");
}
ExprDict &ExprDict::operator =( const ExprDict &rhs) {
assert( false, "NotImplemented");
_expr = rhs._expr;
return *this;
}
// == compares two dictionaries; they must have the same keys (their keys
// must match using CmpKey) and they must have the same values (pointer
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