1 /*
2 * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "opto/regalloc.hpp"
27
28 static const int NodeRegsOverflowSize = 200;
29
30 void (*PhaseRegAlloc::_alloc_statistics[MAX_REG_ALLOCATORS])();
31 int PhaseRegAlloc::_num_allocators = 0;
32 #ifndef PRODUCT
33 int PhaseRegAlloc::_total_framesize = 0;
34 int PhaseRegAlloc::_max_framesize = 0;
35 #endif
36
37 PhaseRegAlloc::PhaseRegAlloc( uint unique, PhaseCFG &cfg,
38 Matcher &matcher,
39 void (*pr_stats)() ):
40 Phase(Register_Allocation), _cfg(cfg), _matcher(matcher),
41 _node_oops(Thread::current()->resource_area()),
42 _node_regs(0),
43 _framesize(0xdeadbeef)
44 {
45 int i;
46
47 for (i=0; i < _num_allocators; i++) {
48 if (_alloc_statistics[i] == pr_stats)
49 return;
50 }
51 assert((_num_allocators + 1) < MAX_REG_ALLOCATORS, "too many register allocators");
52 _alloc_statistics[_num_allocators++] = pr_stats;
53 }
54
55
56 //------------------------------reg2offset-------------------------------------
57 int PhaseRegAlloc::reg2offset_unchecked( OptoReg::Name reg ) const {
58 // Slots below _max_in_arg_stack_reg are offset by the entire frame.
59 // Slots above _max_in_arg_stack_reg are frame_slots and are not offset.
60 int slot = (reg < _matcher._new_SP)
61 ? reg - OptoReg::stack0() + _framesize
62 : reg - _matcher._new_SP;
63 // Note: We use the direct formula (reg - SharedInfo::stack0) instead of
64 // OptoReg::reg2stack(reg), in order to avoid asserts in the latter
65 // function. This routine must remain unchecked, so that dump_frame()
66 // can do its work undisturbed.
67 // %%% not really clear why reg2stack would assert here
68
69 return slot*VMRegImpl::stack_slot_size;
70 }
71
72 int PhaseRegAlloc::reg2offset( OptoReg::Name reg ) const {
73
74 // Not allowed in the out-preserve area.
75 // In-preserve area is allowed so Intel can fetch the return pc out.
76 assert( reg < _matcher._old_SP ||
77 (reg >= OptoReg::add(_matcher._old_SP,C->out_preserve_stack_slots()) &&
78 reg < _matcher._in_arg_limit) ||
79 reg >= OptoReg::add(_matcher._new_SP,C->out_preserve_stack_slots()),
80 "register allocated in a preserve area" );
81 return reg2offset_unchecked( reg );
82 }
83
84 //------------------------------offset2reg-------------------------------------
85 OptoReg::Name PhaseRegAlloc::offset2reg(int stk_offset) const {
86 int slot = stk_offset / jintSize;
87 int reg = (slot < (int) _framesize)
88 ? slot + _matcher._new_SP
89 : OptoReg::stack2reg(slot) - _framesize;
90 assert(stk_offset == reg2offset((OptoReg::Name) reg),
91 "offset2reg does not invert properly");
92 return (OptoReg::Name) reg;
93 }
94
95 //------------------------------set_oop----------------------------------------
96 void PhaseRegAlloc::set_oop( const Node *n, bool is_an_oop ) {
97 if( is_an_oop ) {
98 _node_oops.set(n->_idx);
99 }
100 }
101
102 //------------------------------is_oop-----------------------------------------
103 bool PhaseRegAlloc::is_oop( const Node *n ) const {
104 return _node_oops.test(n->_idx) != 0;
105 }
106
107 // Allocate _node_regs table with at least "size" elements
108 void PhaseRegAlloc::alloc_node_regs(int size) {
109 _node_regs_max_index = size + (size >> 1) + NodeRegsOverflowSize;
110 _node_regs = NEW_RESOURCE_ARRAY( OptoRegPair, _node_regs_max_index );
111 // We assume our caller will fill in all elements up to size-1, so
112 // only the extra space we allocate is initialized here.
113 for( uint i = size; i < _node_regs_max_index; ++i )
114 _node_regs[i].set_bad();
115 }
116
117 #ifndef PRODUCT
118 void
119 PhaseRegAlloc::print_statistics() {
120 tty->print_cr("Total frameslots = %d, Max frameslots = %d", _total_framesize, _max_framesize);
121 int i;
122
123 for (i=0; i < _num_allocators; i++) {
124 _alloc_statistics[i]();
125 }
126 }
127 #endif