Mon, 26 Sep 2011 10:24:05 -0700
7081933: Use zeroing elimination optimization for large array
Summary: Don't zero new typeArray during runtime call if the allocation is followed by arraycopy into it.
Reviewed-by: twisti
duke@435 | 1 | /* |
trims@2708 | 2 | * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "opto/compile.hpp" |
stefank@2314 | 27 | #include "opto/regmask.hpp" |
stefank@2314 | 28 | #ifdef TARGET_ARCH_MODEL_x86_32 |
stefank@2314 | 29 | # include "adfiles/ad_x86_32.hpp" |
stefank@2314 | 30 | #endif |
stefank@2314 | 31 | #ifdef TARGET_ARCH_MODEL_x86_64 |
stefank@2314 | 32 | # include "adfiles/ad_x86_64.hpp" |
stefank@2314 | 33 | #endif |
stefank@2314 | 34 | #ifdef TARGET_ARCH_MODEL_sparc |
stefank@2314 | 35 | # include "adfiles/ad_sparc.hpp" |
stefank@2314 | 36 | #endif |
stefank@2314 | 37 | #ifdef TARGET_ARCH_MODEL_zero |
stefank@2314 | 38 | # include "adfiles/ad_zero.hpp" |
stefank@2314 | 39 | #endif |
bobv@2508 | 40 | #ifdef TARGET_ARCH_MODEL_arm |
bobv@2508 | 41 | # include "adfiles/ad_arm.hpp" |
bobv@2508 | 42 | #endif |
bobv@2508 | 43 | #ifdef TARGET_ARCH_MODEL_ppc |
bobv@2508 | 44 | # include "adfiles/ad_ppc.hpp" |
bobv@2508 | 45 | #endif |
duke@435 | 46 | |
duke@435 | 47 | #define RM_SIZE _RM_SIZE /* a constant private to the class RegMask */ |
duke@435 | 48 | |
duke@435 | 49 | //-------------Non-zero bit search methods used by RegMask--------------------- |
duke@435 | 50 | // Find lowest 1, or return 32 if empty |
duke@435 | 51 | int find_lowest_bit( uint32 mask ) { |
duke@435 | 52 | int n = 0; |
duke@435 | 53 | if( (mask & 0xffff) == 0 ) { |
duke@435 | 54 | mask >>= 16; |
duke@435 | 55 | n += 16; |
duke@435 | 56 | } |
duke@435 | 57 | if( (mask & 0xff) == 0 ) { |
duke@435 | 58 | mask >>= 8; |
duke@435 | 59 | n += 8; |
duke@435 | 60 | } |
duke@435 | 61 | if( (mask & 0xf) == 0 ) { |
duke@435 | 62 | mask >>= 4; |
duke@435 | 63 | n += 4; |
duke@435 | 64 | } |
duke@435 | 65 | if( (mask & 0x3) == 0 ) { |
duke@435 | 66 | mask >>= 2; |
duke@435 | 67 | n += 2; |
duke@435 | 68 | } |
duke@435 | 69 | if( (mask & 0x1) == 0 ) { |
duke@435 | 70 | mask >>= 1; |
duke@435 | 71 | n += 1; |
duke@435 | 72 | } |
duke@435 | 73 | if( mask == 0 ) { |
duke@435 | 74 | n = 32; |
duke@435 | 75 | } |
duke@435 | 76 | return n; |
duke@435 | 77 | } |
duke@435 | 78 | |
duke@435 | 79 | // Find highest 1, or return 32 if empty |
duke@435 | 80 | int find_hihghest_bit( uint32 mask ) { |
duke@435 | 81 | int n = 0; |
duke@435 | 82 | if( mask > 0xffff ) { |
duke@435 | 83 | mask >>= 16; |
duke@435 | 84 | n += 16; |
duke@435 | 85 | } |
duke@435 | 86 | if( mask > 0xff ) { |
duke@435 | 87 | mask >>= 8; |
duke@435 | 88 | n += 8; |
duke@435 | 89 | } |
duke@435 | 90 | if( mask > 0xf ) { |
duke@435 | 91 | mask >>= 4; |
duke@435 | 92 | n += 4; |
duke@435 | 93 | } |
duke@435 | 94 | if( mask > 0x3 ) { |
duke@435 | 95 | mask >>= 2; |
duke@435 | 96 | n += 2; |
duke@435 | 97 | } |
duke@435 | 98 | if( mask > 0x1 ) { |
duke@435 | 99 | mask >>= 1; |
duke@435 | 100 | n += 1; |
duke@435 | 101 | } |
duke@435 | 102 | if( mask == 0 ) { |
duke@435 | 103 | n = 32; |
duke@435 | 104 | } |
duke@435 | 105 | return n; |
duke@435 | 106 | } |
duke@435 | 107 | |
duke@435 | 108 | //------------------------------dump------------------------------------------- |
duke@435 | 109 | |
duke@435 | 110 | #ifndef PRODUCT |
duke@435 | 111 | void OptoReg::dump( int r ) { |
duke@435 | 112 | switch( r ) { |
duke@435 | 113 | case Special: tty->print("r---"); break; |
duke@435 | 114 | case Bad: tty->print("rBAD"); break; |
duke@435 | 115 | default: |
duke@435 | 116 | if( r < _last_Mach_Reg ) tty->print(Matcher::regName[r]); |
duke@435 | 117 | else tty->print("rS%d",r); |
duke@435 | 118 | break; |
duke@435 | 119 | } |
duke@435 | 120 | } |
duke@435 | 121 | #endif |
duke@435 | 122 | |
duke@435 | 123 | |
duke@435 | 124 | //============================================================================= |
duke@435 | 125 | const RegMask RegMask::Empty( |
duke@435 | 126 | # define BODY(I) 0, |
duke@435 | 127 | FORALL_BODY |
duke@435 | 128 | # undef BODY |
duke@435 | 129 | 0 |
duke@435 | 130 | ); |
duke@435 | 131 | |
duke@435 | 132 | //------------------------------find_first_pair-------------------------------- |
duke@435 | 133 | // Find the lowest-numbered register pair in the mask. Return the |
duke@435 | 134 | // HIGHEST register number in the pair, or BAD if no pairs. |
duke@435 | 135 | OptoReg::Name RegMask::find_first_pair() const { |
duke@435 | 136 | VerifyPairs(); |
duke@435 | 137 | for( int i = 0; i < RM_SIZE; i++ ) { |
duke@435 | 138 | if( _A[i] ) { // Found some bits |
duke@435 | 139 | int bit = _A[i] & -_A[i]; // Extract low bit |
duke@435 | 140 | // Convert to bit number, return hi bit in pair |
duke@435 | 141 | return OptoReg::Name((i<<_LogWordBits)+find_lowest_bit(bit)+1); |
duke@435 | 142 | } |
duke@435 | 143 | } |
duke@435 | 144 | return OptoReg::Bad; |
duke@435 | 145 | } |
duke@435 | 146 | |
duke@435 | 147 | //------------------------------ClearToPairs----------------------------------- |
duke@435 | 148 | // Clear out partial bits; leave only bit pairs |
duke@435 | 149 | void RegMask::ClearToPairs() { |
duke@435 | 150 | for( int i = 0; i < RM_SIZE; i++ ) { |
duke@435 | 151 | int bits = _A[i]; |
duke@435 | 152 | bits &= ((bits & 0x55555555)<<1); // 1 hi-bit set for each pair |
duke@435 | 153 | bits |= (bits>>1); // Smear 1 hi-bit into a pair |
duke@435 | 154 | _A[i] = bits; |
duke@435 | 155 | } |
duke@435 | 156 | VerifyPairs(); |
duke@435 | 157 | } |
duke@435 | 158 | |
duke@435 | 159 | //------------------------------SmearToPairs----------------------------------- |
duke@435 | 160 | // Smear out partial bits; leave only bit pairs |
duke@435 | 161 | void RegMask::SmearToPairs() { |
duke@435 | 162 | for( int i = 0; i < RM_SIZE; i++ ) { |
duke@435 | 163 | int bits = _A[i]; |
duke@435 | 164 | bits |= ((bits & 0x55555555)<<1); // Smear lo bit hi per pair |
duke@435 | 165 | bits |= ((bits & 0xAAAAAAAA)>>1); // Smear hi bit lo per pair |
duke@435 | 166 | _A[i] = bits; |
duke@435 | 167 | } |
duke@435 | 168 | VerifyPairs(); |
duke@435 | 169 | } |
duke@435 | 170 | |
duke@435 | 171 | //------------------------------is_aligned_pairs------------------------------- |
duke@435 | 172 | bool RegMask::is_aligned_Pairs() const { |
duke@435 | 173 | // Assert that the register mask contains only bit pairs. |
duke@435 | 174 | for( int i = 0; i < RM_SIZE; i++ ) { |
duke@435 | 175 | int bits = _A[i]; |
duke@435 | 176 | while( bits ) { // Check bits for pairing |
duke@435 | 177 | int bit = bits & -bits; // Extract low bit |
duke@435 | 178 | // Low bit is not odd means its mis-aligned. |
duke@435 | 179 | if( (bit & 0x55555555) == 0 ) return false; |
duke@435 | 180 | bits -= bit; // Remove bit from mask |
duke@435 | 181 | // Check for aligned adjacent bit |
duke@435 | 182 | if( (bits & (bit<<1)) == 0 ) return false; |
duke@435 | 183 | bits -= (bit<<1); // Remove other halve of pair |
duke@435 | 184 | } |
duke@435 | 185 | } |
duke@435 | 186 | return true; |
duke@435 | 187 | } |
duke@435 | 188 | |
duke@435 | 189 | //------------------------------is_bound1-------------------------------------- |
duke@435 | 190 | // Return TRUE if the mask contains a single bit |
duke@435 | 191 | int RegMask::is_bound1() const { |
duke@435 | 192 | if( is_AllStack() ) return false; |
duke@435 | 193 | int bit = -1; // Set to hold the one bit allowed |
duke@435 | 194 | for( int i = 0; i < RM_SIZE; i++ ) { |
duke@435 | 195 | if( _A[i] ) { // Found some bits |
duke@435 | 196 | if( bit != -1 ) return false; // Already had bits, so fail |
duke@435 | 197 | bit = _A[i] & -_A[i]; // Extract 1 bit from mask |
duke@435 | 198 | if( bit != _A[i] ) return false; // Found many bits, so fail |
duke@435 | 199 | } |
duke@435 | 200 | } |
duke@435 | 201 | // True for both the empty mask and for a single bit |
duke@435 | 202 | return true; |
duke@435 | 203 | } |
duke@435 | 204 | |
duke@435 | 205 | //------------------------------is_bound2-------------------------------------- |
duke@435 | 206 | // Return TRUE if the mask contains an adjacent pair of bits and no other bits. |
duke@435 | 207 | int RegMask::is_bound2() const { |
duke@435 | 208 | if( is_AllStack() ) return false; |
duke@435 | 209 | |
duke@435 | 210 | int bit = -1; // Set to hold the one bit allowed |
duke@435 | 211 | for( int i = 0; i < RM_SIZE; i++ ) { |
duke@435 | 212 | if( _A[i] ) { // Found some bits |
duke@435 | 213 | if( bit != -1 ) return false; // Already had bits, so fail |
duke@435 | 214 | bit = _A[i] & -(_A[i]); // Extract 1 bit from mask |
duke@435 | 215 | if( (bit << 1) != 0 ) { // Bit pair stays in same word? |
duke@435 | 216 | if( (bit | (bit<<1)) != _A[i] ) |
duke@435 | 217 | return false; // Require adjacent bit pair and no more bits |
duke@435 | 218 | } else { // Else its a split-pair case |
duke@435 | 219 | if( bit != _A[i] ) return false; // Found many bits, so fail |
duke@435 | 220 | i++; // Skip iteration forward |
duke@435 | 221 | if( _A[i] != 1 ) return false; // Require 1 lo bit in next word |
duke@435 | 222 | } |
duke@435 | 223 | } |
duke@435 | 224 | } |
duke@435 | 225 | // True for both the empty mask and for a bit pair |
duke@435 | 226 | return true; |
duke@435 | 227 | } |
duke@435 | 228 | |
duke@435 | 229 | //------------------------------is_UP------------------------------------------ |
duke@435 | 230 | // UP means register only, Register plus stack, or stack only is DOWN |
duke@435 | 231 | bool RegMask::is_UP() const { |
duke@435 | 232 | // Quick common case check for DOWN (any stack slot is legal) |
duke@435 | 233 | if( is_AllStack() ) |
duke@435 | 234 | return false; |
duke@435 | 235 | // Slower check for any stack bits set (also DOWN) |
duke@435 | 236 | if( overlap(Matcher::STACK_ONLY_mask) ) |
duke@435 | 237 | return false; |
duke@435 | 238 | // Not DOWN, so must be UP |
duke@435 | 239 | return true; |
duke@435 | 240 | } |
duke@435 | 241 | |
duke@435 | 242 | //------------------------------Size------------------------------------------- |
duke@435 | 243 | // Compute size of register mask in bits |
duke@435 | 244 | uint RegMask::Size() const { |
duke@435 | 245 | extern uint8 bitsInByte[256]; |
duke@435 | 246 | uint sum = 0; |
duke@435 | 247 | for( int i = 0; i < RM_SIZE; i++ ) |
duke@435 | 248 | sum += |
duke@435 | 249 | bitsInByte[(_A[i]>>24) & 0xff] + |
duke@435 | 250 | bitsInByte[(_A[i]>>16) & 0xff] + |
duke@435 | 251 | bitsInByte[(_A[i]>> 8) & 0xff] + |
duke@435 | 252 | bitsInByte[ _A[i] & 0xff]; |
duke@435 | 253 | return sum; |
duke@435 | 254 | } |
duke@435 | 255 | |
duke@435 | 256 | #ifndef PRODUCT |
duke@435 | 257 | //------------------------------print------------------------------------------ |
duke@435 | 258 | void RegMask::dump( ) const { |
duke@435 | 259 | tty->print("["); |
duke@435 | 260 | RegMask rm = *this; // Structure copy into local temp |
duke@435 | 261 | |
duke@435 | 262 | OptoReg::Name start = rm.find_first_elem(); // Get a register |
duke@435 | 263 | if( OptoReg::is_valid(start) ) { // Check for empty mask |
duke@435 | 264 | rm.Remove(start); // Yank from mask |
duke@435 | 265 | OptoReg::dump(start); // Print register |
duke@435 | 266 | OptoReg::Name last = start; |
duke@435 | 267 | |
duke@435 | 268 | // Now I have printed an initial register. |
duke@435 | 269 | // Print adjacent registers as "rX-rZ" instead of "rX,rY,rZ". |
duke@435 | 270 | // Begin looping over the remaining registers. |
duke@435 | 271 | while( 1 ) { // |
duke@435 | 272 | OptoReg::Name reg = rm.find_first_elem(); // Get a register |
duke@435 | 273 | if( !OptoReg::is_valid(reg) ) |
duke@435 | 274 | break; // Empty mask, end loop |
duke@435 | 275 | rm.Remove(reg); // Yank from mask |
duke@435 | 276 | |
duke@435 | 277 | if( last+1 == reg ) { // See if they are adjacent |
duke@435 | 278 | // Adjacent registers just collect into long runs, no printing. |
duke@435 | 279 | last = reg; |
duke@435 | 280 | } else { // Ending some kind of run |
duke@435 | 281 | if( start == last ) { // 1-register run; no special printing |
duke@435 | 282 | } else if( start+1 == last ) { |
duke@435 | 283 | tty->print(","); // 2-register run; print as "rX,rY" |
duke@435 | 284 | OptoReg::dump(last); |
duke@435 | 285 | } else { // Multi-register run; print as "rX-rZ" |
duke@435 | 286 | tty->print("-"); |
duke@435 | 287 | OptoReg::dump(last); |
duke@435 | 288 | } |
duke@435 | 289 | tty->print(","); // Seperate start of new run |
duke@435 | 290 | start = last = reg; // Start a new register run |
duke@435 | 291 | OptoReg::dump(start); // Print register |
duke@435 | 292 | } // End of if ending a register run or not |
duke@435 | 293 | } // End of while regmask not empty |
duke@435 | 294 | |
duke@435 | 295 | if( start == last ) { // 1-register run; no special printing |
duke@435 | 296 | } else if( start+1 == last ) { |
duke@435 | 297 | tty->print(","); // 2-register run; print as "rX,rY" |
duke@435 | 298 | OptoReg::dump(last); |
duke@435 | 299 | } else { // Multi-register run; print as "rX-rZ" |
duke@435 | 300 | tty->print("-"); |
duke@435 | 301 | OptoReg::dump(last); |
duke@435 | 302 | } |
duke@435 | 303 | if( rm.is_AllStack() ) tty->print("..."); |
duke@435 | 304 | } |
duke@435 | 305 | tty->print("]"); |
duke@435 | 306 | } |
duke@435 | 307 | #endif |