Mercurial > hg > graal-compiler
view src/share/vm/interpreter/rewriter.cpp @ 235:9c2ecc2ffb12 jdk7-b31
Merge
author | trims |
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date | Fri, 11 Jul 2008 01:14:44 -0700 |
parents | a61af66fc99e |
children | 9a25e0c45327 |
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/* * Copyright 1998-2005 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * */ # include "incls/_precompiled.incl" # include "incls/_rewriter.cpp.incl" // Computes an index_map (new_index -> original_index) for contant pool entries // that are referred to by the interpreter at runtime via the constant pool cache. void Rewriter::compute_index_maps(constantPoolHandle pool, intArray*& index_map, intStack*& inverse_index_map) { const int length = pool->length(); index_map = new intArray(length, -1); // Choose an initial value large enough that we don't get frequent // calls to grow(). inverse_index_map = new intStack(length / 2); for (int i = 0; i < length; i++) { switch (pool->tag_at(i).value()) { case JVM_CONSTANT_Fieldref : // fall through case JVM_CONSTANT_Methodref : // fall through case JVM_CONSTANT_InterfaceMethodref: { index_map->at_put(i, inverse_index_map->length()); inverse_index_map->append(i); } } } } // Creates a constant pool cache given an inverse_index_map constantPoolCacheHandle Rewriter::new_constant_pool_cache(intArray& inverse_index_map, TRAPS) { const int length = inverse_index_map.length(); constantPoolCacheOop cache = oopFactory::new_constantPoolCache(length, CHECK_(constantPoolCacheHandle())); cache->initialize(inverse_index_map); return constantPoolCacheHandle(THREAD, cache); } // The new finalization semantics says that registration of // finalizable objects must be performed on successful return from the // Object.<init> constructor. We could implement this trivially if // <init> were never rewritten but since JVMTI allows this to occur, a // more complicated solution is required. A special return bytecode // is used only by Object.<init> to signal the finalization // registration point. Additionally local 0 must be preserved so it's // available to pass to the registration function. For simplicty we // require that local 0 is never overwritten so it's available as an // argument for registration. void Rewriter::rewrite_Object_init(methodHandle method, TRAPS) { RawBytecodeStream bcs(method); while (!bcs.is_last_bytecode()) { Bytecodes::Code opcode = bcs.raw_next(); switch (opcode) { case Bytecodes::_return: *bcs.bcp() = Bytecodes::_return_register_finalizer; break; case Bytecodes::_istore: case Bytecodes::_lstore: case Bytecodes::_fstore: case Bytecodes::_dstore: case Bytecodes::_astore: if (bcs.get_index() != 0) continue; // fall through case Bytecodes::_istore_0: case Bytecodes::_lstore_0: case Bytecodes::_fstore_0: case Bytecodes::_dstore_0: case Bytecodes::_astore_0: THROW_MSG(vmSymbols::java_lang_IncompatibleClassChangeError(), "can't overwrite local 0 in Object.<init>"); break; } } } // Rewrites a method given the index_map information methodHandle Rewriter::rewrite_method(methodHandle method, intArray& index_map, TRAPS) { int nof_jsrs = 0; bool has_monitor_bytecodes = false; { // We cannot tolerate a GC in this block, because we've // cached the bytecodes in 'code_base'. If the methodOop // moves, the bytecodes will also move. No_Safepoint_Verifier nsv; Bytecodes::Code c; // Bytecodes and their length const address code_base = method->code_base(); const int code_length = method->code_size(); int bc_length; for (int bci = 0; bci < code_length; bci += bc_length) { address bcp = code_base + bci; c = (Bytecodes::Code)(*bcp); // Since we have the code, see if we can get the length // directly. Some more complicated bytecodes will report // a length of zero, meaning we need to make another method // call to calculate the length. bc_length = Bytecodes::length_for(c); if (bc_length == 0) { bc_length = Bytecodes::length_at(bcp); // length_at will put us at the bytecode after the one modified // by 'wide'. We don't currently examine any of the bytecodes // modified by wide, but in case we do in the future... if (c == Bytecodes::_wide) { c = (Bytecodes::Code)bcp[1]; } } assert(bc_length != 0, "impossible bytecode length"); switch (c) { case Bytecodes::_lookupswitch : { #ifndef CC_INTERP Bytecode_lookupswitch* bc = Bytecode_lookupswitch_at(bcp); bc->set_code( bc->number_of_pairs() < BinarySwitchThreshold ? Bytecodes::_fast_linearswitch : Bytecodes::_fast_binaryswitch ); #endif break; } case Bytecodes::_getstatic : // fall through case Bytecodes::_putstatic : // fall through case Bytecodes::_getfield : // fall through case Bytecodes::_putfield : // fall through case Bytecodes::_invokevirtual : // fall through case Bytecodes::_invokespecial : // fall through case Bytecodes::_invokestatic : // fall through case Bytecodes::_invokeinterface: { address p = bcp + 1; Bytes::put_native_u2(p, index_map[Bytes::get_Java_u2(p)]); break; } case Bytecodes::_jsr : // fall through case Bytecodes::_jsr_w : nof_jsrs++; break; case Bytecodes::_monitorenter : // fall through case Bytecodes::_monitorexit : has_monitor_bytecodes = true; break; } } } // Update access flags if (has_monitor_bytecodes) { method->set_has_monitor_bytecodes(); } // The present of a jsr bytecode implies that the method might potentially // have to be rewritten, so we run the oopMapGenerator on the method if (nof_jsrs > 0) { method->set_has_jsrs(); ResolveOopMapConflicts romc(method); methodHandle original_method = method; method = romc.do_potential_rewrite(CHECK_(methodHandle())); if (method() != original_method()) { // Insert invalid bytecode into original methodOop and set // interpreter entrypoint, so that a executing this method // will manifest itself in an easy recognizable form. address bcp = original_method->bcp_from(0); *bcp = (u1)Bytecodes::_shouldnotreachhere; int kind = Interpreter::method_kind(original_method); original_method->set_interpreter_kind(kind); } // Update monitor matching info. if (romc.monitor_safe()) { method->set_guaranteed_monitor_matching(); } } // Setup method entrypoints for compiler and interpreter method->link_method(method, CHECK_(methodHandle())); return method; } void Rewriter::rewrite(instanceKlassHandle klass, TRAPS) { // gather starting points ResourceMark rm(THREAD); constantPoolHandle pool (THREAD, klass->constants()); objArrayHandle methods (THREAD, klass->methods()); assert(pool->cache() == NULL, "constant pool cache must not be set yet"); // determine index maps for methodOop rewriting intArray* index_map = NULL; intStack* inverse_index_map = NULL; compute_index_maps(pool, index_map, inverse_index_map); // allocate constant pool cache constantPoolCacheHandle cache = new_constant_pool_cache(*inverse_index_map, CHECK); pool->set_cache(cache()); cache->set_constant_pool(pool()); if (RegisterFinalizersAtInit && klass->name() == vmSymbols::java_lang_Object()) { int i = methods->length(); while (i-- > 0) { methodOop method = (methodOop)methods->obj_at(i); if (method->intrinsic_id() == vmIntrinsics::_Object_init) { // rewrite the return bytecodes of Object.<init> to register the // object for finalization if needed. methodHandle m(THREAD, method); rewrite_Object_init(m, CHECK); break; } } } // rewrite methods { int i = methods->length(); while (i-- > 0) { methodHandle m(THREAD, (methodOop)methods->obj_at(i)); m = rewrite_method(m, *index_map, CHECK); // Method might have gotten rewritten. methods->obj_at_put(i, m()); } } }