1 /*
2 * Copyright (c) 2000, 2013, 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
PhaseRegAlloc(uint unique,PhaseCFG & cfg,Matcher & matcher,void (* pr_stats)())37 PhaseRegAlloc::PhaseRegAlloc( uint unique, PhaseCFG &cfg,
38 Matcher &matcher,
39 void (*pr_stats)() ):
40 Phase(Register_Allocation),
41 _node_regs(0),
42 _node_regs_max_index(0),
43 _node_oops(Thread::current()->resource_area()),
44 _cfg(cfg),
45 _framesize(0xdeadbeef),
46 _matcher(matcher)
47 {
48 int i;
49
50 for (i=0; i < _num_allocators; i++) {
51 if (_alloc_statistics[i] == pr_stats)
52 return;
53 }
54 assert((_num_allocators + 1) < MAX_REG_ALLOCATORS, "too many register allocators");
55 _alloc_statistics[_num_allocators++] = pr_stats;
56 }
57
58
59 //------------------------------reg2offset-------------------------------------
reg2offset_unchecked(OptoReg::Name reg) const60 int PhaseRegAlloc::reg2offset_unchecked( OptoReg::Name reg ) const {
61 // Slots below _max_in_arg_stack_reg are offset by the entire frame.
62 // Slots above _max_in_arg_stack_reg are frame_slots and are not offset.
63 int slot = (reg < _matcher._new_SP)
64 ? reg - OptoReg::stack0() + _framesize
65 : reg - _matcher._new_SP;
66 // Note: We use the direct formula (reg - SharedInfo::stack0) instead of
67 // OptoReg::reg2stack(reg), in order to avoid asserts in the latter
68 // function. This routine must remain unchecked, so that dump_frame()
69 // can do its work undisturbed.
70 // %%% not really clear why reg2stack would assert here
71
72 return slot*VMRegImpl::stack_slot_size;
73 }
74
reg2offset(OptoReg::Name reg) const75 int PhaseRegAlloc::reg2offset( OptoReg::Name reg ) const {
76
77 // Not allowed in the out-preserve area.
78 // In-preserve area is allowed so Intel can fetch the return pc out.
79 assert( reg < _matcher._old_SP ||
80 (reg >= OptoReg::add(_matcher._old_SP,C->out_preserve_stack_slots()) &&
81 reg < _matcher._in_arg_limit) ||
82 reg >= OptoReg::add(_matcher._new_SP, C->out_preserve_stack_slots()) ||
83 // Allow return_addr in the out-preserve area.
84 reg == _matcher.return_addr(),
85 "register allocated in a preserve area" );
86 return reg2offset_unchecked( reg );
87 }
88
89 //------------------------------offset2reg-------------------------------------
offset2reg(int stk_offset) const90 OptoReg::Name PhaseRegAlloc::offset2reg(int stk_offset) const {
91 int slot = stk_offset / jintSize;
92 int reg = (slot < (int) _framesize)
93 ? slot + _matcher._new_SP
94 : OptoReg::stack2reg(slot) - _framesize;
95 assert(stk_offset == reg2offset((OptoReg::Name) reg),
96 "offset2reg does not invert properly");
97 return (OptoReg::Name) reg;
98 }
99
100 //------------------------------set_oop----------------------------------------
set_oop(const Node * n,bool is_an_oop)101 void PhaseRegAlloc::set_oop( const Node *n, bool is_an_oop ) {
102 if( is_an_oop ) {
103 _node_oops.set(n->_idx);
104 }
105 }
106
107 //------------------------------is_oop-----------------------------------------
is_oop(const Node * n) const108 bool PhaseRegAlloc::is_oop( const Node *n ) const {
109 return _node_oops.test(n->_idx) != 0;
110 }
111
112 // Allocate _node_regs table with at least "size" elements
alloc_node_regs(int size)113 void PhaseRegAlloc::alloc_node_regs(int size) {
114 _node_regs_max_index = size + (size >> 1) + NodeRegsOverflowSize;
115 _node_regs = NEW_RESOURCE_ARRAY( OptoRegPair, _node_regs_max_index );
116 // We assume our caller will fill in all elements up to size-1, so
117 // only the extra space we allocate is initialized here.
118 for( uint i = size; i < _node_regs_max_index; ++i )
119 _node_regs[i].set_bad();
120 }
121
122 #ifndef PRODUCT
123 void
print_statistics()124 PhaseRegAlloc::print_statistics() {
125 tty->print_cr("Total frameslots = %d, Max frameslots = %d", _total_framesize, _max_framesize);
126 int i;
127
128 for (i=0; i < _num_allocators; i++) {
129 _alloc_statistics[i]();
130 }
131 }
132 #endif
133