/* * Copyright (c) 1999, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ class ValueStack: public CompilationResourceObj { private: IRScope* _scope; // the enclosing scope bool _lock_stack; // indicates that this ValueStack is for an exception site Values _locals; // the locals Values _stack; // the expression stack Values _locks; // the monitor stack (holding the locked values) Value check(ValueTag tag, Value t) { assert(tag == t->type()->tag() || tag == objectTag && t->type()->tag() == addressTag, "types must correspond"); return t; } Value check(ValueTag tag, Value t, Value h) { assert(h->as_HiWord()->lo_word() == t, "incorrect stack pair"); return check(tag, t); } // helper routine static void apply(Values list, ValueVisitor* f); public: // creation ValueStack(IRScope* scope, int locals_size, int max_stack_size); // merging ValueStack* copy(); // returns a copy of this w/ cleared locals ValueStack* copy_locks(); // returns a copy of this w/ cleared locals and stack // Note that when inlining of methods with exception // handlers is enabled, this stack may have a // non-empty expression stack (size defined by // scope()->lock_stack_size()) bool is_same(ValueStack* s); // returns true if this & s's types match (w/o checking locals) bool is_same_across_scopes(ValueStack* s); // same as is_same but returns true even if stacks are in different scopes (used for block merging w/inlining) // accessors IRScope* scope() const { return _scope; } bool is_lock_stack() const { return _lock_stack; } int locals_size() const { return _locals.length(); } int stack_size() const { return _stack.length(); } int locks_size() const { return _locks.length(); } int max_stack_size() const { return _stack.capacity(); } bool stack_is_empty() const { return _stack.is_empty(); } bool no_active_locks() const { return _locks.is_empty(); } ValueStack* caller_state() const; // locals access void clear_locals(); // sets all locals to NULL; // Kill local i. Also kill local i+1 if i was a long or double. void invalidate_local(int i) { Value x = _locals.at(i); if (x != NULL && x->type()->is_double_word()) { assert(_locals.at(i + 1)->as_HiWord()->lo_word() == x, "locals inconsistent"); _locals.at_put(i + 1, NULL); } _locals.at_put(i, NULL); } Value load_local(int i) const { Value x = _locals.at(i); if (x != NULL && x->type()->is_illegal()) return NULL; assert(x == NULL || x->as_HiWord() == NULL, "index points to hi word"); assert(x == NULL || x->type()->is_illegal() || x->type()->is_single_word() || x == _locals.at(i+1)->as_HiWord()->lo_word(), "locals inconsistent"); return x; } Value local_at(int i) const { return _locals.at(i); } // Store x into local i. void store_local(int i, Value x) { // Kill the old value invalidate_local(i); _locals.at_put(i, x); // Writing a double word can kill other locals if (x != NULL && x->type()->is_double_word()) { // If x + i was the start of a double word local then kill i + 2. Value x2 = _locals.at(i + 1); if (x2 != NULL && x2->type()->is_double_word()) { _locals.at_put(i + 2, NULL); } // If x is a double word local, also update i + 1. #ifdef ASSERT _locals.at_put(i + 1, x->hi_word()); #else _locals.at_put(i + 1, NULL); #endif } // If x - 1 was the start of a double word local then kill i - 1. if (i > 0) { Value prev = _locals.at(i - 1); if (prev != NULL && prev->type()->is_double_word()) { _locals.at_put(i - 1, NULL); } } } void replace_locals(ValueStack* with); // stack access Value stack_at(int i) const { Value x = _stack.at(i); assert(x->as_HiWord() == NULL, "index points to hi word"); assert(x->type()->is_single_word() || x->subst() == _stack.at(i+1)->as_HiWord()->lo_word(), "stack inconsistent"); return x; } Value stack_at_inc(int& i) const { Value x = stack_at(i); i += x->type()->size(); return x; } // pinning support void pin_stack_for_linear_scan(); // iteration void values_do(ValueVisitor* f); // untyped manipulation (for dup_x1, etc.) void clear_stack() { _stack.clear(); } void truncate_stack(int size) { _stack.trunc_to(size); } void raw_push(Value t) { _stack.push(t); } Value raw_pop() { return _stack.pop(); } // typed manipulation void ipush(Value t) { _stack.push(check(intTag , t)); } void fpush(Value t) { _stack.push(check(floatTag , t)); } void apush(Value t) { _stack.push(check(objectTag , t)); } void rpush(Value t) { _stack.push(check(addressTag, t)); } #ifdef ASSERT // in debug mode, use HiWord for 2-word values void lpush(Value t) { _stack.push(check(longTag , t)); _stack.push(new HiWord(t)); } void dpush(Value t) { _stack.push(check(doubleTag , t)); _stack.push(new HiWord(t)); } #else // in optimized mode, use NULL for 2-word values void lpush(Value t) { _stack.push(check(longTag , t)); _stack.push(NULL); } void dpush(Value t) { _stack.push(check(doubleTag , t)); _stack.push(NULL); } #endif // ASSERT void push(ValueType* type, Value t) { switch (type->tag()) { case intTag : ipush(t); return; case longTag : lpush(t); return; case floatTag : fpush(t); return; case doubleTag : dpush(t); return; case objectTag : apush(t); return; case addressTag: rpush(t); return; } ShouldNotReachHere(); } Value ipop() { return check(intTag , _stack.pop()); } Value fpop() { return check(floatTag , _stack.pop()); } Value apop() { return check(objectTag , _stack.pop()); } Value rpop() { return check(addressTag, _stack.pop()); } #ifdef ASSERT // in debug mode, check for HiWord consistency Value lpop() { Value h = _stack.pop(); return check(longTag , _stack.pop(), h); } Value dpop() { Value h = _stack.pop(); return check(doubleTag, _stack.pop(), h); } #else // in optimized mode, ignore HiWord since it is NULL Value lpop() { _stack.pop(); return check(longTag , _stack.pop()); } Value dpop() { _stack.pop(); return check(doubleTag, _stack.pop()); } #endif // ASSERT Value pop(ValueType* type) { switch (type->tag()) { case intTag : return ipop(); case longTag : return lpop(); case floatTag : return fpop(); case doubleTag : return dpop(); case objectTag : return apop(); case addressTag: return rpop(); } ShouldNotReachHere(); return NULL; } Values* pop_arguments(int argument_size); // locks access int lock (IRScope* scope, Value obj); int unlock(); Value lock_at(int i) const { return _locks.at(i); } // Inlining support ValueStack* push_scope(IRScope* scope); // "Push" new scope, returning new resulting stack // Preserves stack and locks, destroys locals ValueStack* pop_scope(); // "Pop" topmost scope, returning new resulting stack // Preserves stack and locks, destroys locals // SSA form IR support void setup_phi_for_stack(BlockBegin* b, int index); void setup_phi_for_local(BlockBegin* b, int index); // debugging void print() PRODUCT_RETURN; void verify() PRODUCT_RETURN; }; // Macro definitions for simple iteration of stack and local values of a ValueStack // The macros can be used like a for-loop. All variables (state, index and value) // must be defined before the loop. // When states are nested because of inlining, the stack of the innermost state // cumulates also the stack of the nested states. In contrast, the locals of all // states must be iterated each. // Use the following code pattern to iterate all stack values and all nested local values: // // ValueStack* state = ... // state that is iterated // int index; // current loop index (overwritten in loop) // Value value; // value at current loop index (overwritten in loop) // // for_each_stack_value(state, index, value { // do something with value and index // } // // for_each_state(state) { // for_each_local_value(state, index, value) { // do something with value and index // } // } // as an invariant, state is NULL now // construct a unique variable name with the line number where the macro is used #define temp_var3(x) temp__ ## x #define temp_var2(x) temp_var3(x) #define temp_var temp_var2(__LINE__) #define for_each_state(state) \ for (; state != NULL; state = state->caller_state()) #define for_each_local_value(state, index, value) \ int temp_var = state->locals_size(); \ for (index = 0; \ index < temp_var && (value = state->local_at(index), true); \ index += (value == NULL || value->type()->is_illegal() ? 1 : value->type()->size())) \ if (value != NULL) #define for_each_stack_value(state, index, value) \ int temp_var = state->stack_size(); \ for (index = 0; \ index < temp_var && (value = state->stack_at(index), true); \ index += value->type()->size()) #define for_each_lock_value(state, index, value) \ int temp_var = state->locks_size(); \ for (index = 0; \ index < temp_var && (value = state->lock_at(index), true); \ index++) \ if (value != NULL) // Macro definition for simple iteration of all state values of a ValueStack // Because the code cannot be executed in a single loop, the code must be passed // as a macro parameter. // Use the following code pattern to iterate all stack values and all nested local values: // // ValueStack* state = ... // state that is iterated // for_each_state_value(state, value, // do something with value (note that this is a macro parameter) // ); #define for_each_state_value(v_state, v_value, v_code) \ { \ int cur_index; \ ValueStack* cur_state = v_state; \ Value v_value; \ { \ for_each_stack_value(cur_state, cur_index, v_value) { \ v_code; \ } \ } \ for_each_state(cur_state) { \ for_each_local_value(cur_state, cur_index, v_value) { \ v_code; \ } \ } \ } // Macro definition for simple iteration of all phif functions of a block, i.e all // phi functions of the ValueStack where the block matches. // Use the following code pattern to iterate all phi functions of a block: // // BlockBegin* block = ... // block that is iterated // for_each_phi_function(block, phi, // do something with the phi function phi (note that this is a macro parameter) // ); #define for_each_phi_fun(v_block, v_phi, v_code) \ { \ int cur_index; \ ValueStack* cur_state = v_block->state(); \ Value value; \ { \ for_each_stack_value(cur_state, cur_index, value) { \ Phi* v_phi = value->as_Phi(); \ if (v_phi != NULL && v_phi->block() == v_block) { \ v_code; \ } \ } \ } \ { \ for_each_local_value(cur_state, cur_index, value) { \ Phi* v_phi = value->as_Phi(); \ if (v_phi != NULL && v_phi->block() == v_block) { \ v_code; \ } \ } \ } \ }