1 /*
2 * Copyright (c) 1997, 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/compile.hpp"
27 #include "opto/regmask.hpp"
28 #ifdef TARGET_ARCH_MODEL_x86_32
29 # include "adfiles/ad_x86_32.hpp"
30 #endif
31 #ifdef TARGET_ARCH_MODEL_x86_64
32 # include "adfiles/ad_x86_64.hpp"
33 #endif
34 #ifdef TARGET_ARCH_MODEL_sparc
35 # include "adfiles/ad_sparc.hpp"
36 #endif
37 #ifdef TARGET_ARCH_MODEL_zero
38 # include "adfiles/ad_zero.hpp"
39 #endif
40
41 #define RM_SIZE _RM_SIZE /* a constant private to the class RegMask */
42
43 //-------------Non-zero bit search methods used by RegMask---------------------
44 // Find lowest 1, or return 32 if empty
45 int find_lowest_bit( uint32 mask ) {
46 int n = 0;
47 if( (mask & 0xffff) == 0 ) {
48 mask >>= 16;
49 n += 16;
50 }
51 if( (mask & 0xff) == 0 ) {
52 mask >>= 8;
53 n += 8;
54 }
55 if( (mask & 0xf) == 0 ) {
56 mask >>= 4;
57 n += 4;
58 }
59 if( (mask & 0x3) == 0 ) {
60 mask >>= 2;
61 n += 2;
62 }
63 if( (mask & 0x1) == 0 ) {
64 mask >>= 1;
65 n += 1;
66 }
67 if( mask == 0 ) {
68 n = 32;
69 }
70 return n;
71 }
72
73 // Find highest 1, or return 32 if empty
74 int find_hihghest_bit( uint32 mask ) {
75 int n = 0;
76 if( mask > 0xffff ) {
77 mask >>= 16;
78 n += 16;
79 }
80 if( mask > 0xff ) {
81 mask >>= 8;
82 n += 8;
83 }
84 if( mask > 0xf ) {
85 mask >>= 4;
86 n += 4;
87 }
88 if( mask > 0x3 ) {
89 mask >>= 2;
90 n += 2;
91 }
92 if( mask > 0x1 ) {
93 mask >>= 1;
94 n += 1;
95 }
96 if( mask == 0 ) {
97 n = 32;
98 }
99 return n;
100 }
101
102 //------------------------------dump-------------------------------------------
103
104 #ifndef PRODUCT
105 void OptoReg::dump( int r ) {
106 switch( r ) {
107 case Special: tty->print("r---"); break;
108 case Bad: tty->print("rBAD"); break;
109 default:
110 if( r < _last_Mach_Reg ) tty->print(Matcher::regName[r]);
111 else tty->print("rS%d",r);
112 break;
113 }
114 }
115 #endif
116
117
118 //=============================================================================
119 const RegMask RegMask::Empty(
120 # define BODY(I) 0,
121 FORALL_BODY
122 # undef BODY
123 0
124 );
125
126 //------------------------------find_first_pair--------------------------------
127 // Find the lowest-numbered register pair in the mask. Return the
128 // HIGHEST register number in the pair, or BAD if no pairs.
129 OptoReg::Name RegMask::find_first_pair() const {
130 VerifyPairs();
131 for( int i = 0; i < RM_SIZE; i++ ) {
132 if( _A[i] ) { // Found some bits
133 int bit = _A[i] & -_A[i]; // Extract low bit
134 // Convert to bit number, return hi bit in pair
135 return OptoReg::Name((i<<_LogWordBits)+find_lowest_bit(bit)+1);
136 }
137 }
138 return OptoReg::Bad;
139 }
140
141 //------------------------------ClearToPairs-----------------------------------
142 // Clear out partial bits; leave only bit pairs
143 void RegMask::ClearToPairs() {
144 for( int i = 0; i < RM_SIZE; i++ ) {
145 int bits = _A[i];
146 bits &= ((bits & 0x55555555)<<1); // 1 hi-bit set for each pair
147 bits |= (bits>>1); // Smear 1 hi-bit into a pair
148 _A[i] = bits;
149 }
150 VerifyPairs();
151 }
152
153 //------------------------------SmearToPairs-----------------------------------
154 // Smear out partial bits; leave only bit pairs
155 void RegMask::SmearToPairs() {
156 for( int i = 0; i < RM_SIZE; i++ ) {
157 int bits = _A[i];
158 bits |= ((bits & 0x55555555)<<1); // Smear lo bit hi per pair
159 bits |= ((bits & 0xAAAAAAAA)>>1); // Smear hi bit lo per pair
160 _A[i] = bits;
161 }
162 VerifyPairs();
163 }
164
165 //------------------------------is_aligned_pairs-------------------------------
166 bool RegMask::is_aligned_Pairs() const {
167 // Assert that the register mask contains only bit pairs.
168 for( int i = 0; i < RM_SIZE; i++ ) {
169 int bits = _A[i];
170 while( bits ) { // Check bits for pairing
171 int bit = bits & -bits; // Extract low bit
172 // Low bit is not odd means its mis-aligned.
173 if( (bit & 0x55555555) == 0 ) return false;
174 bits -= bit; // Remove bit from mask
175 // Check for aligned adjacent bit
176 if( (bits & (bit<<1)) == 0 ) return false;
177 bits -= (bit<<1); // Remove other halve of pair
178 }
179 }
180 return true;
181 }
182
183 //------------------------------is_bound1--------------------------------------
184 // Return TRUE if the mask contains a single bit
185 int RegMask::is_bound1() const {
186 if( is_AllStack() ) return false;
187 int bit = -1; // Set to hold the one bit allowed
188 for( int i = 0; i < RM_SIZE; i++ ) {
189 if( _A[i] ) { // Found some bits
190 if( bit != -1 ) return false; // Already had bits, so fail
191 bit = _A[i] & -_A[i]; // Extract 1 bit from mask
192 if( bit != _A[i] ) return false; // Found many bits, so fail
193 }
194 }
195 // True for both the empty mask and for a single bit
196 return true;
197 }
198
199 //------------------------------is_bound2--------------------------------------
200 // Return TRUE if the mask contains an adjacent pair of bits and no other bits.
201 int RegMask::is_bound2() const {
202 if( is_AllStack() ) return false;
203
204 int bit = -1; // Set to hold the one bit allowed
205 for( int i = 0; i < RM_SIZE; i++ ) {
206 if( _A[i] ) { // Found some bits
207 if( bit != -1 ) return false; // Already had bits, so fail
208 bit = _A[i] & -(_A[i]); // Extract 1 bit from mask
209 if( (bit << 1) != 0 ) { // Bit pair stays in same word?
210 if( (bit | (bit<<1)) != _A[i] )
211 return false; // Require adjacent bit pair and no more bits
212 } else { // Else its a split-pair case
213 if( bit != _A[i] ) return false; // Found many bits, so fail
214 i++; // Skip iteration forward
215 if( _A[i] != 1 ) return false; // Require 1 lo bit in next word
216 }
217 }
218 }
219 // True for both the empty mask and for a bit pair
220 return true;
221 }
222
223 //------------------------------is_UP------------------------------------------
224 // UP means register only, Register plus stack, or stack only is DOWN
225 bool RegMask::is_UP() const {
226 // Quick common case check for DOWN (any stack slot is legal)
227 if( is_AllStack() )
228 return false;
229 // Slower check for any stack bits set (also DOWN)
230 if( overlap(Matcher::STACK_ONLY_mask) )
231 return false;
232 // Not DOWN, so must be UP
233 return true;
234 }
235
236 //------------------------------Size-------------------------------------------
237 // Compute size of register mask in bits
238 uint RegMask::Size() const {
239 extern uint8 bitsInByte[256];
240 uint sum = 0;
241 for( int i = 0; i < RM_SIZE; i++ )
242 sum +=
243 bitsInByte[(_A[i]>>24) & 0xff] +
244 bitsInByte[(_A[i]>>16) & 0xff] +
245 bitsInByte[(_A[i]>> 8) & 0xff] +
246 bitsInByte[ _A[i] & 0xff];
247 return sum;
248 }
249
250 #ifndef PRODUCT
251 //------------------------------print------------------------------------------
252 void RegMask::dump( ) const {
253 tty->print("[");
254 RegMask rm = *this; // Structure copy into local temp
255
256 OptoReg::Name start = rm.find_first_elem(); // Get a register
257 if( OptoReg::is_valid(start) ) { // Check for empty mask
258 rm.Remove(start); // Yank from mask
259 OptoReg::dump(start); // Print register
260 OptoReg::Name last = start;
261
262 // Now I have printed an initial register.
263 // Print adjacent registers as "rX-rZ" instead of "rX,rY,rZ".
264 // Begin looping over the remaining registers.
265 while( 1 ) { //
266 OptoReg::Name reg = rm.find_first_elem(); // Get a register
267 if( !OptoReg::is_valid(reg) )
268 break; // Empty mask, end loop
269 rm.Remove(reg); // Yank from mask
270
271 if( last+1 == reg ) { // See if they are adjacent
272 // Adjacent registers just collect into long runs, no printing.
273 last = reg;
274 } else { // Ending some kind of run
275 if( start == last ) { // 1-register run; no special printing
276 } else if( start+1 == last ) {
277 tty->print(","); // 2-register run; print as "rX,rY"
278 OptoReg::dump(last);
279 } else { // Multi-register run; print as "rX-rZ"
280 tty->print("-");
281 OptoReg::dump(last);
282 }
283 tty->print(","); // Seperate start of new run
284 start = last = reg; // Start a new register run
285 OptoReg::dump(start); // Print register
286 } // End of if ending a register run or not
287 } // End of while regmask not empty
288
289 if( start == last ) { // 1-register run; no special printing
290 } else if( start+1 == last ) {
291 tty->print(","); // 2-register run; print as "rX,rY"
292 OptoReg::dump(last);
293 } else { // Multi-register run; print as "rX-rZ"
294 tty->print("-");
295 OptoReg::dump(last);
296 }
297 if( rm.is_AllStack() ) tty->print("...");
298 }
299 tty->print("]");
300 }
301 #endif