view src/share/vm/opto/c2compiler.cpp @ 1994:6cd6d394f280

7001033: assert(gch->gc_cause() == GCCause::_scavenge_alot || !gch->incremental_collection_failed()) 7002546: regression on SpecJbb2005 on 7b118 comparing to 7b117 on small heaps Summary: Relaxed assertion checking related to incremental_collection_failed flag to allow for ExplicitGCInvokesConcurrent behaviour where we do not want a failing scavenge to bail to a stop-world collection. Parameterized incremental_collection_will_fail() so we can selectively use, or not use, as appropriate, the statistical prediction at specific use sites. This essentially reverts the scavenge bail-out logic to what it was prior to some recent changes that had inadvertently started using the statistical prediction which can be noisy in the presence of bursty loads. Added some associated verbose non-product debugging messages. Reviewed-by: johnc, tonyp
author ysr
date Tue, 07 Dec 2010 21:55:53 -0800
parents f95d63e2154a
children b92c45f2bc75
line wrap: on
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/*
 * Copyright (c) 1999, 2010, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "opto/c2compiler.hpp"
#include "opto/runtime.hpp"
#ifdef TARGET_ARCH_MODEL_x86_32
# include "adfiles/ad_x86_32.hpp"
#endif
#ifdef TARGET_ARCH_MODEL_x86_64
# include "adfiles/ad_x86_64.hpp"
#endif
#ifdef TARGET_ARCH_MODEL_sparc
# include "adfiles/ad_sparc.hpp"
#endif
#ifdef TARGET_ARCH_MODEL_zero
# include "adfiles/ad_zero.hpp"
#endif


volatile int C2Compiler::_runtimes = uninitialized;

// register information defined by ADLC
extern const char register_save_policy[];
extern const int  register_save_type[];

const char* C2Compiler::retry_no_subsuming_loads() {
  return "retry without subsuming loads";
}
const char* C2Compiler::retry_no_escape_analysis() {
  return "retry without escape analysis";
}
void C2Compiler::initialize_runtime() {

  // Check assumptions used while running ADLC
  Compile::adlc_verification();
  assert(REG_COUNT <= ConcreteRegisterImpl::number_of_registers, "incompatible register counts");

  for (int i = 0; i < ConcreteRegisterImpl::number_of_registers ; i++ ) {
      OptoReg::vm2opto[i] = OptoReg::Bad;
  }

  for( OptoReg::Name i=OptoReg::Name(0); i<OptoReg::Name(REG_COUNT); i = OptoReg::add(i,1) ) {
    VMReg r = OptoReg::as_VMReg(i);
    if (r->is_valid()) {
      OptoReg::vm2opto[r->value()] = i;
    }
  }

  // Check that runtime and architecture description agree on callee-saved-floats
  bool callee_saved_floats = false;
  for( OptoReg::Name i=OptoReg::Name(0); i<OptoReg::Name(_last_Mach_Reg); i = OptoReg::add(i,1) ) {
    // Is there a callee-saved float or double?
    if( register_save_policy[i] == 'E' /* callee-saved */ &&
       (register_save_type[i] == Op_RegF || register_save_type[i] == Op_RegD) ) {
      callee_saved_floats = true;
    }
  }

  DEBUG_ONLY( Node::init_NodeProperty(); )

  Compile::pd_compiler2_init();

  CompilerThread* thread = CompilerThread::current();

  HandleMark  handle_mark(thread);

  OptoRuntime::generate(thread->env());

}


void C2Compiler::initialize() {

  // This method can only be called once per C2Compiler object
  // The first compiler thread that gets here will initialize the
  // small amount of global state (and runtime stubs) that c2 needs.

  // There is a race possible once at startup and then we're fine

  // Note that this is being called from a compiler thread not the
  // main startup thread.

  if (_runtimes != initialized) {
    initialize_runtimes( initialize_runtime, &_runtimes);
  }

  // Mark this compiler object as ready to roll
  mark_initialized();
}

void C2Compiler::compile_method(ciEnv* env,
                                ciMethod* target,
                                int entry_bci) {
  if (!is_initialized()) {
    initialize();
  }
  bool subsume_loads = SubsumeLoads;
  bool do_escape_analysis = DoEscapeAnalysis &&
    !env->jvmti_can_access_local_variables();
  while (!env->failing()) {
    // Attempt to compile while subsuming loads into machine instructions.
    Compile C(env, this, target, entry_bci, subsume_loads, do_escape_analysis);


    // Check result and retry if appropriate.
    if (C.failure_reason() != NULL) {
      if (C.failure_reason_is(retry_no_subsuming_loads())) {
        assert(subsume_loads, "must make progress");
        subsume_loads = false;
        continue;  // retry
      }
      if (C.failure_reason_is(retry_no_escape_analysis())) {
        assert(do_escape_analysis, "must make progress");
        do_escape_analysis = false;
        continue;  // retry
      }
      // Pass any other failure reason up to the ciEnv.
      // Note that serious, irreversible failures are already logged
      // on the ciEnv via env->record_method_not_compilable().
      env->record_failure(C.failure_reason());
    }
    if (StressRecompilation) {
      if (subsume_loads) {
        subsume_loads = false;
        continue;  // retry
      }
      if (do_escape_analysis) {
        do_escape_analysis = false;
        continue;  // retry
      }
    }

    // No retry; just break the loop.
    break;
  }
}


void C2Compiler::print_timers() {
  // do nothing
}