Tue, 18 Dec 2012 10:47:23 -0800
8004536: replace AbstractAssembler emit_word with emit_int16
Reviewed-by: jrose, kvn, twisti
Contributed-by: Morris Meyer <morris.meyer@oracle.com>
duke@435 | 1 | /* |
mikael@4153 | 2 | * Copyright (c) 1997, 2012, 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" |
twisti@4318 | 26 | #include "asm/macroAssembler.hpp" |
twisti@4318 | 27 | #include "asm/macroAssembler.inline.hpp" |
stefank@2314 | 28 | #include "asm/codeBuffer.hpp" |
twisti@4318 | 29 | #include "runtime/atomic.hpp" |
twisti@4318 | 30 | #include "runtime/atomic.inline.hpp" |
stefank@2314 | 31 | #include "runtime/icache.hpp" |
stefank@2314 | 32 | #include "runtime/os.hpp" |
duke@435 | 33 | |
duke@435 | 34 | |
duke@435 | 35 | // Implementation of AbstractAssembler |
duke@435 | 36 | // |
duke@435 | 37 | // The AbstractAssembler is generating code into a CodeBuffer. To make code generation faster, |
duke@435 | 38 | // the assembler keeps a copy of the code buffers boundaries & modifies them when |
duke@435 | 39 | // emitting bytes rather than using the code buffers accessor functions all the time. |
twisti@1040 | 40 | // The code buffer is updated via set_code_end(...) after emitting a whole instruction. |
duke@435 | 41 | |
duke@435 | 42 | AbstractAssembler::AbstractAssembler(CodeBuffer* code) { |
duke@435 | 43 | if (code == NULL) return; |
duke@435 | 44 | CodeSection* cs = code->insts(); |
duke@435 | 45 | cs->clear_mark(); // new assembler kills old mark |
twisti@4317 | 46 | if (cs->start() == NULL) { |
jcoomes@1845 | 47 | vm_exit_out_of_memory(0, err_msg("CodeCache: no room for %s", |
jcoomes@1845 | 48 | code->name())); |
duke@435 | 49 | } |
twisti@4317 | 50 | _code_section = cs; |
twisti@4317 | 51 | _oop_recorder= code->oop_recorder(); |
twisti@4317 | 52 | DEBUG_ONLY( _short_branch_delta = 0; ) |
duke@435 | 53 | } |
duke@435 | 54 | |
duke@435 | 55 | void AbstractAssembler::set_code_section(CodeSection* cs) { |
duke@435 | 56 | assert(cs->outer() == code_section()->outer(), "sanity"); |
duke@435 | 57 | assert(cs->is_allocated(), "need to pre-allocate this section"); |
duke@435 | 58 | cs->clear_mark(); // new assembly into this section kills old mark |
duke@435 | 59 | _code_section = cs; |
duke@435 | 60 | } |
duke@435 | 61 | |
duke@435 | 62 | // Inform CodeBuffer that incoming code and relocation will be for stubs |
duke@435 | 63 | address AbstractAssembler::start_a_stub(int required_space) { |
duke@435 | 64 | CodeBuffer* cb = code(); |
duke@435 | 65 | CodeSection* cs = cb->stubs(); |
duke@435 | 66 | assert(_code_section == cb->insts(), "not in insts?"); |
duke@435 | 67 | if (cs->maybe_expand_to_ensure_remaining(required_space) |
duke@435 | 68 | && cb->blob() == NULL) { |
duke@435 | 69 | return NULL; |
duke@435 | 70 | } |
duke@435 | 71 | set_code_section(cs); |
duke@435 | 72 | return pc(); |
duke@435 | 73 | } |
duke@435 | 74 | |
duke@435 | 75 | // Inform CodeBuffer that incoming code and relocation will be code |
duke@435 | 76 | // Should not be called if start_a_stub() returned NULL |
duke@435 | 77 | void AbstractAssembler::end_a_stub() { |
duke@435 | 78 | assert(_code_section == code()->stubs(), "not in stubs?"); |
duke@435 | 79 | set_code_section(code()->insts()); |
duke@435 | 80 | } |
duke@435 | 81 | |
duke@435 | 82 | // Inform CodeBuffer that incoming code and relocation will be for stubs |
duke@435 | 83 | address AbstractAssembler::start_a_const(int required_space, int required_align) { |
duke@435 | 84 | CodeBuffer* cb = code(); |
duke@435 | 85 | CodeSection* cs = cb->consts(); |
kvn@4316 | 86 | assert(_code_section == cb->insts() || _code_section == cb->stubs(), "not in insts/stubs?"); |
duke@435 | 87 | address end = cs->end(); |
duke@435 | 88 | int pad = -(intptr_t)end & (required_align-1); |
duke@435 | 89 | if (cs->maybe_expand_to_ensure_remaining(pad + required_space)) { |
duke@435 | 90 | if (cb->blob() == NULL) return NULL; |
duke@435 | 91 | end = cs->end(); // refresh pointer |
duke@435 | 92 | } |
duke@435 | 93 | if (pad > 0) { |
duke@435 | 94 | while (--pad >= 0) { *end++ = 0; } |
duke@435 | 95 | cs->set_end(end); |
duke@435 | 96 | } |
duke@435 | 97 | set_code_section(cs); |
duke@435 | 98 | return end; |
duke@435 | 99 | } |
duke@435 | 100 | |
duke@435 | 101 | // Inform CodeBuffer that incoming code and relocation will be code |
kvn@4316 | 102 | // in section cs (insts or stubs). |
kvn@4316 | 103 | void AbstractAssembler::end_a_const(CodeSection* cs) { |
duke@435 | 104 | assert(_code_section == code()->consts(), "not in consts?"); |
kvn@4316 | 105 | set_code_section(cs); |
duke@435 | 106 | } |
duke@435 | 107 | |
duke@435 | 108 | void AbstractAssembler::flush() { |
duke@435 | 109 | ICache::invalidate_range(addr_at(0), offset()); |
duke@435 | 110 | } |
duke@435 | 111 | |
duke@435 | 112 | |
duke@435 | 113 | void AbstractAssembler::a_byte(int x) { |
duke@435 | 114 | emit_byte(x); |
duke@435 | 115 | } |
duke@435 | 116 | |
duke@435 | 117 | |
duke@435 | 118 | void AbstractAssembler::a_long(jint x) { |
duke@435 | 119 | emit_long(x); |
duke@435 | 120 | } |
duke@435 | 121 | |
duke@435 | 122 | |
duke@435 | 123 | void AbstractAssembler::bind(Label& L) { |
duke@435 | 124 | if (L.is_bound()) { |
duke@435 | 125 | // Assembler can bind a label more than once to the same place. |
duke@435 | 126 | guarantee(L.loc() == locator(), "attempt to redefine label"); |
duke@435 | 127 | return; |
duke@435 | 128 | } |
duke@435 | 129 | L.bind_loc(locator()); |
duke@435 | 130 | L.patch_instructions((MacroAssembler*)this); |
duke@435 | 131 | } |
duke@435 | 132 | |
duke@435 | 133 | void AbstractAssembler::generate_stack_overflow_check( int frame_size_in_bytes) { |
duke@435 | 134 | if (UseStackBanging) { |
duke@435 | 135 | // Each code entry causes one stack bang n pages down the stack where n |
duke@435 | 136 | // is configurable by StackBangPages. The setting depends on the maximum |
duke@435 | 137 | // depth of VM call stack or native before going back into java code, |
duke@435 | 138 | // since only java code can raise a stack overflow exception using the |
duke@435 | 139 | // stack banging mechanism. The VM and native code does not detect stack |
duke@435 | 140 | // overflow. |
duke@435 | 141 | // The code in JavaCalls::call() checks that there is at least n pages |
duke@435 | 142 | // available, so all entry code needs to do is bang once for the end of |
duke@435 | 143 | // this shadow zone. |
duke@435 | 144 | // The entry code may need to bang additional pages if the framesize |
duke@435 | 145 | // is greater than a page. |
duke@435 | 146 | |
duke@435 | 147 | const int page_size = os::vm_page_size(); |
duke@435 | 148 | int bang_end = StackShadowPages*page_size; |
duke@435 | 149 | |
duke@435 | 150 | // This is how far the previous frame's stack banging extended. |
duke@435 | 151 | const int bang_end_safe = bang_end; |
duke@435 | 152 | |
duke@435 | 153 | if (frame_size_in_bytes > page_size) { |
duke@435 | 154 | bang_end += frame_size_in_bytes; |
duke@435 | 155 | } |
duke@435 | 156 | |
duke@435 | 157 | int bang_offset = bang_end_safe; |
duke@435 | 158 | while (bang_offset <= bang_end) { |
duke@435 | 159 | // Need at least one stack bang at end of shadow zone. |
duke@435 | 160 | bang_stack_with_offset(bang_offset); |
duke@435 | 161 | bang_offset += page_size; |
duke@435 | 162 | } |
duke@435 | 163 | } // end (UseStackBanging) |
duke@435 | 164 | } |
duke@435 | 165 | |
duke@435 | 166 | void Label::add_patch_at(CodeBuffer* cb, int branch_loc) { |
duke@435 | 167 | assert(_loc == -1, "Label is unbound"); |
duke@435 | 168 | if (_patch_index < PatchCacheSize) { |
duke@435 | 169 | _patches[_patch_index] = branch_loc; |
duke@435 | 170 | } else { |
duke@435 | 171 | if (_patch_overflow == NULL) { |
duke@435 | 172 | _patch_overflow = cb->create_patch_overflow(); |
duke@435 | 173 | } |
duke@435 | 174 | _patch_overflow->push(branch_loc); |
duke@435 | 175 | } |
duke@435 | 176 | ++_patch_index; |
duke@435 | 177 | } |
duke@435 | 178 | |
duke@435 | 179 | void Label::patch_instructions(MacroAssembler* masm) { |
duke@435 | 180 | assert(is_bound(), "Label is bound"); |
duke@435 | 181 | CodeBuffer* cb = masm->code(); |
duke@435 | 182 | int target_sect = CodeBuffer::locator_sect(loc()); |
duke@435 | 183 | address target = cb->locator_address(loc()); |
duke@435 | 184 | while (_patch_index > 0) { |
duke@435 | 185 | --_patch_index; |
duke@435 | 186 | int branch_loc; |
duke@435 | 187 | if (_patch_index >= PatchCacheSize) { |
duke@435 | 188 | branch_loc = _patch_overflow->pop(); |
duke@435 | 189 | } else { |
duke@435 | 190 | branch_loc = _patches[_patch_index]; |
duke@435 | 191 | } |
duke@435 | 192 | int branch_sect = CodeBuffer::locator_sect(branch_loc); |
duke@435 | 193 | address branch = cb->locator_address(branch_loc); |
duke@435 | 194 | if (branch_sect == CodeBuffer::SECT_CONSTS) { |
duke@435 | 195 | // The thing to patch is a constant word. |
duke@435 | 196 | *(address*)branch = target; |
duke@435 | 197 | continue; |
duke@435 | 198 | } |
duke@435 | 199 | |
duke@435 | 200 | #ifdef ASSERT |
duke@435 | 201 | // Cross-section branches only work if the |
duke@435 | 202 | // intermediate section boundaries are frozen. |
duke@435 | 203 | if (target_sect != branch_sect) { |
duke@435 | 204 | for (int n = MIN2(target_sect, branch_sect), |
duke@435 | 205 | nlimit = (target_sect + branch_sect) - n; |
duke@435 | 206 | n < nlimit; n++) { |
duke@435 | 207 | CodeSection* cs = cb->code_section(n); |
duke@435 | 208 | assert(cs->is_frozen(), "cross-section branch needs stable offsets"); |
duke@435 | 209 | } |
duke@435 | 210 | } |
duke@435 | 211 | #endif //ASSERT |
duke@435 | 212 | |
duke@435 | 213 | // Push the target offset into the branch instruction. |
duke@435 | 214 | masm->pd_patch_instruction(branch, target); |
duke@435 | 215 | } |
duke@435 | 216 | } |
duke@435 | 217 | |
jrose@1057 | 218 | struct DelayedConstant { |
jrose@1057 | 219 | typedef void (*value_fn_t)(); |
jrose@1057 | 220 | BasicType type; |
jrose@1057 | 221 | intptr_t value; |
jrose@1057 | 222 | value_fn_t value_fn; |
jrose@1057 | 223 | // This limit of 20 is generous for initial uses. |
jrose@1057 | 224 | // The limit needs to be large enough to store the field offsets |
jrose@1057 | 225 | // into classes which do not have statically fixed layouts. |
jrose@1057 | 226 | // (Initial use is for method handle object offsets.) |
jrose@1057 | 227 | // Look for uses of "delayed_value" in the source code |
jrose@1057 | 228 | // and make sure this number is generous enough to handle all of them. |
jrose@1057 | 229 | enum { DC_LIMIT = 20 }; |
jrose@1057 | 230 | static DelayedConstant delayed_constants[DC_LIMIT]; |
jrose@1057 | 231 | static DelayedConstant* add(BasicType type, value_fn_t value_fn); |
jrose@1057 | 232 | bool match(BasicType t, value_fn_t cfn) { |
jrose@1057 | 233 | return type == t && value_fn == cfn; |
jrose@1057 | 234 | } |
jrose@1057 | 235 | static void update_all(); |
jrose@1057 | 236 | }; |
jrose@1057 | 237 | |
jrose@1057 | 238 | DelayedConstant DelayedConstant::delayed_constants[DC_LIMIT]; |
jrose@1057 | 239 | // Default C structure initialization rules have the following effect here: |
jrose@1057 | 240 | // = { { (BasicType)0, (intptr_t)NULL }, ... }; |
jrose@1057 | 241 | |
jrose@1057 | 242 | DelayedConstant* DelayedConstant::add(BasicType type, |
jrose@1057 | 243 | DelayedConstant::value_fn_t cfn) { |
jrose@1057 | 244 | for (int i = 0; i < DC_LIMIT; i++) { |
jrose@1057 | 245 | DelayedConstant* dcon = &delayed_constants[i]; |
jrose@1057 | 246 | if (dcon->match(type, cfn)) |
jrose@1057 | 247 | return dcon; |
jrose@1057 | 248 | if (dcon->value_fn == NULL) { |
jrose@1057 | 249 | // (cmpxchg not because this is multi-threaded but because I'm paranoid) |
jrose@1057 | 250 | if (Atomic::cmpxchg_ptr(CAST_FROM_FN_PTR(void*, cfn), &dcon->value_fn, NULL) == NULL) { |
jrose@1057 | 251 | dcon->type = type; |
jrose@1057 | 252 | return dcon; |
jrose@1057 | 253 | } |
jrose@1057 | 254 | } |
jrose@1057 | 255 | } |
jrose@1057 | 256 | // If this assert is hit (in pre-integration testing!) then re-evaluate |
jrose@1057 | 257 | // the comment on the definition of DC_LIMIT. |
jrose@1057 | 258 | guarantee(false, "too many delayed constants"); |
jrose@1057 | 259 | return NULL; |
jrose@1057 | 260 | } |
jrose@1057 | 261 | |
jrose@1057 | 262 | void DelayedConstant::update_all() { |
jrose@1057 | 263 | for (int i = 0; i < DC_LIMIT; i++) { |
jrose@1057 | 264 | DelayedConstant* dcon = &delayed_constants[i]; |
jrose@1057 | 265 | if (dcon->value_fn != NULL && dcon->value == 0) { |
jrose@1057 | 266 | typedef int (*int_fn_t)(); |
jrose@1057 | 267 | typedef address (*address_fn_t)(); |
jrose@1057 | 268 | switch (dcon->type) { |
jrose@1057 | 269 | case T_INT: dcon->value = (intptr_t) ((int_fn_t) dcon->value_fn)(); break; |
jrose@1057 | 270 | case T_ADDRESS: dcon->value = (intptr_t) ((address_fn_t)dcon->value_fn)(); break; |
jrose@1057 | 271 | } |
jrose@1057 | 272 | } |
jrose@1057 | 273 | } |
jrose@1057 | 274 | } |
jrose@1057 | 275 | |
twisti@3969 | 276 | RegisterOrConstant AbstractAssembler::delayed_value(int(*value_fn)(), Register tmp, int offset) { |
twisti@3969 | 277 | intptr_t val = (intptr_t) (*value_fn)(); |
twisti@3969 | 278 | if (val != 0) return val + offset; |
twisti@3969 | 279 | return delayed_value_impl(delayed_value_addr(value_fn), tmp, offset); |
twisti@3969 | 280 | } |
twisti@3969 | 281 | RegisterOrConstant AbstractAssembler::delayed_value(address(*value_fn)(), Register tmp, int offset) { |
twisti@3969 | 282 | intptr_t val = (intptr_t) (*value_fn)(); |
twisti@3969 | 283 | if (val != 0) return val + offset; |
twisti@3969 | 284 | return delayed_value_impl(delayed_value_addr(value_fn), tmp, offset); |
twisti@3969 | 285 | } |
jrose@1057 | 286 | intptr_t* AbstractAssembler::delayed_value_addr(int(*value_fn)()) { |
jrose@1057 | 287 | DelayedConstant* dcon = DelayedConstant::add(T_INT, (DelayedConstant::value_fn_t) value_fn); |
jrose@1057 | 288 | return &dcon->value; |
jrose@1057 | 289 | } |
jrose@1057 | 290 | intptr_t* AbstractAssembler::delayed_value_addr(address(*value_fn)()) { |
jrose@1057 | 291 | DelayedConstant* dcon = DelayedConstant::add(T_ADDRESS, (DelayedConstant::value_fn_t) value_fn); |
jrose@1057 | 292 | return &dcon->value; |
jrose@1057 | 293 | } |
jrose@1057 | 294 | void AbstractAssembler::update_delayed_values() { |
jrose@1057 | 295 | DelayedConstant::update_all(); |
jrose@1057 | 296 | } |
jrose@1057 | 297 | |
jrose@1057 | 298 | |
jrose@1057 | 299 | |
duke@435 | 300 | |
duke@435 | 301 | void AbstractAssembler::block_comment(const char* comment) { |
duke@435 | 302 | if (sect() == CodeBuffer::SECT_INSTS) { |
duke@435 | 303 | code_section()->outer()->block_comment(offset(), comment); |
duke@435 | 304 | } |
duke@435 | 305 | } |
duke@435 | 306 | |
coleenp@672 | 307 | bool MacroAssembler::needs_explicit_null_check(intptr_t offset) { |
coleenp@672 | 308 | // Exception handler checks the nmethod's implicit null checks table |
coleenp@672 | 309 | // only when this method returns false. |
kvn@1077 | 310 | #ifdef _LP64 |
kvn@1077 | 311 | if (UseCompressedOops && Universe::narrow_oop_base() != NULL) { |
kvn@1077 | 312 | assert (Universe::heap() != NULL, "java heap should be initialized"); |
coleenp@672 | 313 | // The first page after heap_base is unmapped and |
coleenp@672 | 314 | // the 'offset' is equal to [heap_base + offset] for |
coleenp@672 | 315 | // narrow oop implicit null checks. |
kvn@1077 | 316 | uintptr_t base = (uintptr_t)Universe::narrow_oop_base(); |
kvn@1077 | 317 | if ((uintptr_t)offset >= base) { |
coleenp@672 | 318 | // Normalize offset for the next check. |
kvn@1077 | 319 | offset = (intptr_t)(pointer_delta((void*)offset, (void*)base, 1)); |
coleenp@672 | 320 | } |
coleenp@672 | 321 | } |
kvn@1077 | 322 | #endif |
coleenp@672 | 323 | return offset < 0 || os::vm_page_size() <= offset; |
coleenp@672 | 324 | } |