/* * Copyright (c) 1999, 2019, 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 { public: enum Kind {
Parsing, // During abstract interpretation in GraphBuilder
CallerState, // Caller state when inlining
StateBefore, // Before before execution of instruction
StateAfter, // After execution of instruction
ExceptionState, // Exception handling of instruction
EmptyExceptionState, // Exception handling of instructions not covered by an xhandler
BlockBeginState // State of BlockBegin instruction with phi functions of this block
};
private:
IRScope* _scope; // the enclosing scope
ValueStack* _caller_state; int _bci;
Kind _kind;
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 == NULL, "hi-word of doubleword value must be NULL"); return check(tag, t);
}
// locals access void clear_locals(); // sets all locals to NULL;
void invalidate_local(int i) {
assert(!_locals.at(i)->type()->is_double_word() ||
_locals.at(i + 1) == NULL, "hi-word of doubleword value must be NULL");
_locals.at_put(i, NULL);
}
Value local_at(int i) const {
Value x = _locals.at(i);
assert(x == NULL || !x->type()->is_double_word() ||
_locals.at(i + 1) == NULL, "hi-word of doubleword value must be NULL"); return x;
}
void store_local(int i, Value x) { // When overwriting local i, check if i - 1 was the start of a // double word local and kill it. if (i > 0) {
Value prev = _locals.at(i - 1); if (prev != NULL && prev->type()->is_double_word()) {
_locals.at_put(i - 1, NULL);
}
}
_locals.at_put(i, x); if (x->type()->is_double_word()) { // hi-word of doubleword value is always NULL
_locals.at_put(i + 1, NULL);
}
}
// stack access
Value stack_at(int i) const {
Value x = _stack.at(i);
assert(!x->type()->is_double_word() ||
_stack.at(i + 1) == NULL, "hi-word of doubleword value must be NULL"); return x;
}
Value stack_at_inc(int& i) const {
Value x = stack_at(i);
i += x->type()->size(); return x;
}
void stack_at_put(int i, Value x) {
_stack.at_put(i, x);
}
// pinning support void pin_stack_for_linear_scan();
// 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) // );
// Macro definition for simple iteration of all phi 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) // );
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