regmask.cpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1997, 2006, 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 "incls/_precompiled.incl" 26#include "incls/_regmask.cpp.incl" 27 28#define RM_SIZE _RM_SIZE /* a constant private to the class RegMask */ 29 30//-------------Non-zero bit search methods used by RegMask--------------------- 31// Find lowest 1, or return 32 if empty 32int find_lowest_bit( uint32 mask ) { 33 int n = 0; 34 if( (mask & 0xffff) == 0 ) { 35 mask >>= 16; 36 n += 16; 37 } 38 if( (mask & 0xff) == 0 ) { 39 mask >>= 8; 40 n += 8; 41 } 42 if( (mask & 0xf) == 0 ) { 43 mask >>= 4; 44 n += 4; 45 } 46 if( (mask & 0x3) == 0 ) { 47 mask >>= 2; 48 n += 2; 49 } 50 if( (mask & 0x1) == 0 ) { 51 mask >>= 1; 52 n += 1; 53 } 54 if( mask == 0 ) { 55 n = 32; 56 } 57 return n; 58} 59 60// Find highest 1, or return 32 if empty 61int find_hihghest_bit( uint32 mask ) { 62 int n = 0; 63 if( mask > 0xffff ) { 64 mask >>= 16; 65 n += 16; 66 } 67 if( mask > 0xff ) { 68 mask >>= 8; 69 n += 8; 70 } 71 if( mask > 0xf ) { 72 mask >>= 4; 73 n += 4; 74 } 75 if( mask > 0x3 ) { 76 mask >>= 2; 77 n += 2; 78 } 79 if( mask > 0x1 ) { 80 mask >>= 1; 81 n += 1; 82 } 83 if( mask == 0 ) { 84 n = 32; 85 } 86 return n; 87} 88 89//------------------------------dump------------------------------------------- 90 91#ifndef PRODUCT 92void OptoReg::dump( int r ) { 93 switch( r ) { 94 case Special: tty->print("r---"); break; 95 case Bad: tty->print("rBAD"); break; 96 default: 97 if( r < _last_Mach_Reg ) tty->print(Matcher::regName[r]); 98 else tty->print("rS%d",r); 99 break; 100 } 101} 102#endif 103 104 105//============================================================================= 106const RegMask RegMask::Empty( 107# define BODY(I) 0, 108 FORALL_BODY 109# undef BODY 110 0 111); 112 113//------------------------------find_first_pair-------------------------------- 114// Find the lowest-numbered register pair in the mask. Return the 115// HIGHEST register number in the pair, or BAD if no pairs. 116OptoReg::Name RegMask::find_first_pair() const { 117 VerifyPairs(); 118 for( int i = 0; i < RM_SIZE; i++ ) { 119 if( _A[i] ) { // Found some bits 120 int bit = _A[i] & -_A[i]; // Extract low bit 121 // Convert to bit number, return hi bit in pair 122 return OptoReg::Name((i<<_LogWordBits)+find_lowest_bit(bit)+1); 123 } 124 } 125 return OptoReg::Bad; 126} 127 128//------------------------------ClearToPairs----------------------------------- 129// Clear out partial bits; leave only bit pairs 130void RegMask::ClearToPairs() { 131 for( int i = 0; i < RM_SIZE; i++ ) { 132 int bits = _A[i]; 133 bits &= ((bits & 0x55555555)<<1); // 1 hi-bit set for each pair 134 bits |= (bits>>1); // Smear 1 hi-bit into a pair 135 _A[i] = bits; 136 } 137 VerifyPairs(); 138} 139 140//------------------------------SmearToPairs----------------------------------- 141// Smear out partial bits; leave only bit pairs 142void RegMask::SmearToPairs() { 143 for( int i = 0; i < RM_SIZE; i++ ) { 144 int bits = _A[i]; 145 bits |= ((bits & 0x55555555)<<1); // Smear lo bit hi per pair 146 bits |= ((bits & 0xAAAAAAAA)>>1); // Smear hi bit lo per pair 147 _A[i] = bits; 148 } 149 VerifyPairs(); 150} 151 152//------------------------------is_aligned_pairs------------------------------- 153bool RegMask::is_aligned_Pairs() const { 154 // Assert that the register mask contains only bit pairs. 155 for( int i = 0; i < RM_SIZE; i++ ) { 156 int bits = _A[i]; 157 while( bits ) { // Check bits for pairing 158 int bit = bits & -bits; // Extract low bit 159 // Low bit is not odd means its mis-aligned. 160 if( (bit & 0x55555555) == 0 ) return false; 161 bits -= bit; // Remove bit from mask 162 // Check for aligned adjacent bit 163 if( (bits & (bit<<1)) == 0 ) return false; 164 bits -= (bit<<1); // Remove other halve of pair 165 } 166 } 167 return true; 168} 169 170//------------------------------is_bound1-------------------------------------- 171// Return TRUE if the mask contains a single bit 172int RegMask::is_bound1() const { 173 if( is_AllStack() ) return false; 174 int bit = -1; // Set to hold the one bit allowed 175 for( int i = 0; i < RM_SIZE; i++ ) { 176 if( _A[i] ) { // Found some bits 177 if( bit != -1 ) return false; // Already had bits, so fail 178 bit = _A[i] & -_A[i]; // Extract 1 bit from mask 179 if( bit != _A[i] ) return false; // Found many bits, so fail 180 } 181 } 182 // True for both the empty mask and for a single bit 183 return true; 184} 185 186//------------------------------is_bound2-------------------------------------- 187// Return TRUE if the mask contains an adjacent pair of bits and no other bits. 188int RegMask::is_bound2() const { 189 if( is_AllStack() ) return false; 190 191 int bit = -1; // Set to hold the one bit allowed 192 for( int i = 0; i < RM_SIZE; i++ ) { 193 if( _A[i] ) { // Found some bits 194 if( bit != -1 ) return false; // Already had bits, so fail 195 bit = _A[i] & -(_A[i]); // Extract 1 bit from mask 196 if( (bit << 1) != 0 ) { // Bit pair stays in same word? 197 if( (bit | (bit<<1)) != _A[i] ) 198 return false; // Require adjacent bit pair and no more bits 199 } else { // Else its a split-pair case 200 if( bit != _A[i] ) return false; // Found many bits, so fail 201 i++; // Skip iteration forward 202 if( _A[i] != 1 ) return false; // Require 1 lo bit in next word 203 } 204 } 205 } 206 // True for both the empty mask and for a bit pair 207 return true; 208} 209 210//------------------------------is_UP------------------------------------------ 211// UP means register only, Register plus stack, or stack only is DOWN 212bool RegMask::is_UP() const { 213 // Quick common case check for DOWN (any stack slot is legal) 214 if( is_AllStack() ) 215 return false; 216 // Slower check for any stack bits set (also DOWN) 217 if( overlap(Matcher::STACK_ONLY_mask) ) 218 return false; 219 // Not DOWN, so must be UP 220 return true; 221} 222 223//------------------------------Size------------------------------------------- 224// Compute size of register mask in bits 225uint RegMask::Size() const { 226 extern uint8 bitsInByte[256]; 227 uint sum = 0; 228 for( int i = 0; i < RM_SIZE; i++ ) 229 sum += 230 bitsInByte[(_A[i]>>24) & 0xff] + 231 bitsInByte[(_A[i]>>16) & 0xff] + 232 bitsInByte[(_A[i]>> 8) & 0xff] + 233 bitsInByte[ _A[i] & 0xff]; 234 return sum; 235} 236 237#ifndef PRODUCT 238//------------------------------print------------------------------------------ 239void RegMask::dump( ) const { 240 tty->print("["); 241 RegMask rm = *this; // Structure copy into local temp 242 243 OptoReg::Name start = rm.find_first_elem(); // Get a register 244 if( OptoReg::is_valid(start) ) { // Check for empty mask 245 rm.Remove(start); // Yank from mask 246 OptoReg::dump(start); // Print register 247 OptoReg::Name last = start; 248 249 // Now I have printed an initial register. 250 // Print adjacent registers as "rX-rZ" instead of "rX,rY,rZ". 251 // Begin looping over the remaining registers. 252 while( 1 ) { // 253 OptoReg::Name reg = rm.find_first_elem(); // Get a register 254 if( !OptoReg::is_valid(reg) ) 255 break; // Empty mask, end loop 256 rm.Remove(reg); // Yank from mask 257 258 if( last+1 == reg ) { // See if they are adjacent 259 // Adjacent registers just collect into long runs, no printing. 260 last = reg; 261 } else { // Ending some kind of run 262 if( start == last ) { // 1-register run; no special printing 263 } else if( start+1 == last ) { 264 tty->print(","); // 2-register run; print as "rX,rY" 265 OptoReg::dump(last); 266 } else { // Multi-register run; print as "rX-rZ" 267 tty->print("-"); 268 OptoReg::dump(last); 269 } 270 tty->print(","); // Seperate start of new run 271 start = last = reg; // Start a new register run 272 OptoReg::dump(start); // Print register 273 } // End of if ending a register run or not 274 } // End of while regmask not empty 275 276 if( start == last ) { // 1-register run; no special printing 277 } else if( start+1 == last ) { 278 tty->print(","); // 2-register run; print as "rX,rY" 279 OptoReg::dump(last); 280 } else { // Multi-register run; print as "rX-rZ" 281 tty->print("-"); 282 OptoReg::dump(last); 283 } 284 if( rm.is_AllStack() ) tty->print("..."); 285 } 286 tty->print("]"); 287} 288#endif 289