Quelle os_bsd_aarch64.cpp Sprache: C

/*
* Copyright (c) 1999, 2022, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2014, Red Hat Inc. All rights reserved.
* Copyright (c) 2021, Azul Systems, 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/

// no precompiled headers
#include "asm/macroAssembler.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeCache.hpp"
#include "code/icBuffer.hpp"
#include "code/vtableStubs.hpp"
#include "interpreter/interpreter.hpp"
#include "jvm.h"
#include "logging/log.hpp"
#include "memory/allocation.inline.hpp"
#include "os_bsd.hpp"
#include "os_posix.hpp"
#include "prims/jniFastGetField.hpp"
#include "prims/jvm_misc.hpp"
#include "runtime/arguments.hpp"
#include "runtime/frame.inline.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/javaThread.hpp"
#include "runtime/mutexLocker.hpp"
#include "runtime/osThread.hpp"
#include "runtime/safepointMechanism.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/stubRoutines.hpp"
#include "runtime/timer.hpp"
#include "signals_posix.hpp"
#include "utilities/align.hpp"
#include "utilities/events.hpp"
#include "utilities/vmError.hpp"

// put OS-includes here
# include <sys/types.h>
# include <sys/mman.h>
# include <pthread.h>
# include <signal.h>
# include <errno.h>
# include <dlfcn.h>
# include <stdlib.h>
# include <stdio.h>
# include <unistd.h>
# include <sys/resource.h>
# include <sys/stat.h>
# include <sys/time.h>
# include <sys/utsname.h>
# include <sys/socket.h>
# include <sys/wait.h>
# include <pwd.h>
# include <poll.h>
#ifndef __OpenBSD__
# include <ucontext.h>
#endif

#if !defined(__APPLE__) && !defined(__NetBSD__)
# include <pthread_np.h>
#endif

#define SPELL_REG_SP "sp"
#define SPELL_REG_FP "fp"

#ifdef __APPLE__
// see darwin-xnu/osfmk/mach/arm/_structs.h

// 10.5 UNIX03 member name prefixes
#define DU3_PREFIX(s, m) __ ## s.__ ## m
#endif

#define context_x    uc_mcontext->DU3_PREFIX(ss,x)
#define context_fp   uc_mcontext->DU3_PREFIX(ss,fp)
#define context_lr   uc_mcontext->DU3_PREFIX(ss,lr)
#define context_sp   uc_mcontext->DU3_PREFIX(ss,sp)
#define context_pc   uc_mcontext->DU3_PREFIX(ss,pc)
#define context_cpsr uc_mcontext->DU3_PREFIX(ss,cpsr)
#define context_esr  uc_mcontext->DU3_PREFIX(es,esr)

address os::current_stack_pointer() {
#if defined(__clang__) || defined(__llvm__)
  void *sp;
  __asm__("mov %0, " SPELL_REG_SP : "=r"(sp));
  return (address) sp;
#else
  register void *sp __asm__ (SPELL_REG_SP);
  return (address) sp;
#endif
}

char* os::non_memory_address_word() {
  // Must never look like an address returned by reserve_memory,
  // even in its subfields (as defined by the CPU immediate fields,
  // if the CPU splits constants across multiple instructions).

  // the return value used in computation of Universe::non_oop_word(), which
  // is loaded by cpu/aarch64 by MacroAssembler::movptr(Register, uintptr_t)
  return (char*) 0xffffffffffff;
}

address os::Posix::ucontext_get_pc(const ucontext_t * uc) {
  return (address)uc->context_pc;
}

void os::Posix::ucontext_set_pc(ucontext_t * uc, address pc) {
  uc->context_pc = (intptr_t)pc ;
}

intptr_t* os::Bsd::ucontext_get_sp(const ucontext_t * uc) {
  return (intptr_t*)uc->context_sp;
}

intptr_t* os::Bsd::ucontext_get_fp(const ucontext_t * uc) {
  return (intptr_t*)uc->context_fp;
}

address os::fetch_frame_from_context(const void* ucVoid,
                    intptr_t** ret_sp, intptr_t** ret_fp) {

  address epc;
  const ucontext_t* uc = (const ucontext_t*)ucVoid;

  if (uc != NULL) {
    epc = os::Posix::ucontext_get_pc(uc);
    if (ret_sp) *ret_sp = os::Bsd::ucontext_get_sp(uc);
    if (ret_fp) *ret_fp = os::Bsd::ucontext_get_fp(uc);
  } else {
    epc = NULL;
    if (ret_sp) *ret_sp = (intptr_t *)NULL;
    if (ret_fp) *ret_fp = (intptr_t *)NULL;
  }

  return epc;
}

frame os::fetch_frame_from_context(const void* ucVoid) {
  intptr_t* sp;
  intptr_t* fp;
  address epc = fetch_frame_from_context(ucVoid, &sp, &fp);
  return frame(sp, fp, epc);
}

frame os::fetch_compiled_frame_from_context(const void* ucVoid) {
  const ucontext_t* uc = (const ucontext_t*)ucVoid;
  // In compiled code, the stack banging is performed before LR
  // has been saved in the frame.  LR is live, and SP and FP
  // belong to the caller.
  intptr_t* fp = os::Bsd::ucontext_get_fp(uc);
  intptr_t* sp = os::Bsd::ucontext_get_sp(uc);
  address pc = (address)(uc->context_lr
                         - NativeInstruction::instruction_size);
  return frame(sp, fp, pc);
}

// JVM compiled with -fno-omit-frame-pointer, so RFP is saved on the stack.
frame os::get_sender_for_C_frame(frame* fr) {
  return frame(fr->link(), fr->link(), fr->sender_pc());
}

NOINLINE frame os::current_frame() {
  intptr_t *fp = *(intptr_t **)__builtin_frame_address(0);
  frame myframe((intptr_t*)os::current_stack_pointer(),
                (intptr_t*)fp,
                CAST_FROM_FN_PTR(address, os::current_frame));
  if (os::is_first_C_frame(&myframe)) {
    // stack is not walkable
    return frame();
  } else {
    return os::get_sender_for_C_frame(&myframe);
  }
}

ATTRIBUTE_PRINTF(6, 7)
static void report_and_die(Thread* thread, void* context, const char* filename, int lineno, const char* message,
                             const char* detail_fmt, ...) {
  va_list va;
  va_start(va, detail_fmt);
  VMError::report_and_die(thread, context, filename, lineno, message, detail_fmt, va);
  va_end(va);
}

bool PosixSignals::pd_hotspot_signal_handler(int sig, siginfo_t* info,
                                             ucontext_t* uc, JavaThread* thread) {
  // Enable WXWrite: this function is called by the signal handler at arbitrary
  // point of execution.
  ThreadWXEnable wx(WXWrite, thread);

  // decide if this trap can be handled by a stub
  address stub = NULL;

  address pc          = NULL;

  //%note os_trap_1
  if (info != NULL && uc != NULL && thread != NULL) {
    pc = (address) os::Posix::ucontext_get_pc(uc);

    // Handle ALL stack overflow variations here
    if (sig == SIGSEGV || sig == SIGBUS) {
      address addr = (address) info->si_addr;

      // Make sure the high order byte is sign extended, as it may be masked away by the hardware.
      if ((uintptr_t(addr) & (uintptr_t(1) << 55)) != 0) {
        addr = address(uintptr_t(addr) | (uintptr_t(0xFF) << 56));
      }

      // check if fault address is within thread stack
      if (thread->is_in_full_stack(addr)) {
        // stack overflow
        if (os::Posix::handle_stack_overflow(thread, addr, pc, uc, &stub)) {
          return true; // continue
        }
      }
    }

    // We test if stub is already set (by the stack overflow code
    // above) so it is not overwritten by the code that follows. This
    // check is not required on other platforms, because on other
    // platforms we check for SIGSEGV only or SIGBUS only, where here
    // we have to check for both SIGSEGV and SIGBUS.
    if (thread->thread_state() == _thread_in_Java && stub == NULL) {
      // Java thread running in Java code => find exception handler if any
      // a fault inside compiled code, the interpreter, or a stub

      // Handle signal from NativeJump::patch_verified_entry().
      if ((sig == SIGILL)
          && nativeInstruction_at(pc)->is_sigill_not_entrant()) {
        if (TraceTraps) {
          tty->print_cr("trap: not_entrant");
        }
        stub = SharedRuntime::get_handle_wrong_method_stub();
      } else if ((sig == SIGSEGV || sig == SIGBUS) && SafepointMechanism::is_poll_address((address)info->si_addr)) {
        stub = SharedRuntime::get_poll_stub(pc);
#if defined(__APPLE__)
      // 32-bit Darwin reports a SIGBUS for nearly all memory access exceptions.
      // 64-bit Darwin may also use a SIGBUS (seen with compressed oops).
      // Catching SIGBUS here prevents the implicit SIGBUS NULL check below from
      // being called, so only do so if the implicit NULL check is not necessary.
      } else if (sig == SIGBUS && !MacroAssembler::uses_implicit_null_check(info->si_addr)) {
#else
      } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) {
#endif
        // BugId 4454115: A read from a MappedByteBuffer can fault
        // here if the underlying file has been truncated.
        // Do not crash the VM in such a case.
        CodeBlob* cb = CodeCache::find_blob(pc);
        CompiledMethod* nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
        bool is_unsafe_arraycopy = (thread->doing_unsafe_access() && UnsafeCopyMemory::contains_pc(pc));
        if ((nm != NULL && nm->has_unsafe_access()) || is_unsafe_arraycopy) {
          address next_pc = pc + NativeCall::instruction_size;
          if (is_unsafe_arraycopy) {
            next_pc = UnsafeCopyMemory::page_error_continue_pc(pc);
          }
          stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
        }
      } else if (sig == SIGILL && nativeInstruction_at(pc)->is_stop()) {
        // Pull a pointer to the error message out of the instruction
        // stream.
        const uint64_t *detail_msg_ptr
          = (uint64_t*)(pc + NativeInstruction::instruction_size);
        const char *detail_msg = (const char *)*detail_msg_ptr;
        const char *msg = "stop";
        if (TraceTraps) {
          tty->print_cr("trap: %s: (SIGILL)", msg);
        }

        // End life with a fatal error, message and detail message and the context.
        // Note: no need to do any post-processing here (e.g. signal chaining)
        report_and_die(thread, uc, NULL, 0, msg, "%s", detail_msg);
        ShouldNotReachHere();

      } else if (sig == SIGFPE &&
          (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) {
        stub =
          SharedRuntime::
          continuation_for_implicit_exception(thread,
                                              pc,
                                              SharedRuntime::
                                              IMPLICIT_DIVIDE_BY_ZERO);
      } else if ((sig == SIGSEGV || sig == SIGBUS) &&
                 MacroAssembler::uses_implicit_null_check(info->si_addr)) {
          // Determination of interpreter/vtable stub/compiled code null exception
          stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
      }
    } else if ((thread->thread_state() == _thread_in_vm ||
                 thread->thread_state() == _thread_in_native) &&
               sig == SIGBUS && /* info->si_code == BUS_OBJERR && */
               thread->doing_unsafe_access()) {
      address next_pc = pc + NativeCall::instruction_size;
      if (UnsafeCopyMemory::contains_pc(pc)) {
        next_pc = UnsafeCopyMemory::page_error_continue_pc(pc);
      }
      stub = SharedRuntime::handle_unsafe_access(thread, next_pc);
    }

    // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
    // and the heap gets shrunk before the field access.
    if ((sig == SIGSEGV) || (sig == SIGBUS)) {
      address addr = JNI_FastGetField::find_slowcase_pc(pc);
      if (addr != (address)-1) {
        stub = addr;
      }
    }
  }

  if (stub != NULL) {
    // save all thread context in case we need to restore it
    if (thread != NULL) thread->set_saved_exception_pc(pc);

    os::Posix::ucontext_set_pc(uc, stub);
    return true;
  }

  return false; // Mute compiler
}

void os::Bsd::init_thread_fpu_state(void) {
}

////////////////////////////////////////////////////////////////////////////////
// thread stack

// Minimum usable stack sizes required to get to user code. Space for
// HotSpot guard pages is added later.
size_t os::_compiler_thread_min_stack_allowed = 72 * K;
size_t os::_java_thread_min_stack_allowed = 72 * K;
size_t os::_vm_internal_thread_min_stack_allowed = 72 * K;

// return default stack size for thr_type
size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
  // default stack size (compiler thread needs larger stack)
  size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
  return s;
}

static void current_stack_region(address * bottom, size_t * size) {
#ifdef __APPLE__
  pthread_t self = pthread_self();
  void *stacktop = pthread_get_stackaddr_np(self);
  *size = pthread_get_stacksize_np(self);
  *bottom = (address) stacktop - *size;
#elif defined(__OpenBSD__)
  stack_t ss;
  int rslt = pthread_stackseg_np(pthread_self(), &ss);

  if (rslt != 0)
    fatal("pthread_stackseg_np failed with error = %d", rslt);

  *bottom = (address)((char *)ss.ss_sp - ss.ss_size);
  *size   = ss.ss_size;
#else
  pthread_attr_t attr;

  int rslt = pthread_attr_init(&attr);

  // JVM needs to know exact stack location, abort if it fails
  if (rslt != 0)
    fatal("pthread_attr_init failed with error = %d", rslt);

  rslt = pthread_attr_get_np(pthread_self(), &attr);

  if (rslt != 0)
    fatal("pthread_attr_get_np failed with error = %d", rslt);

  if (pthread_attr_getstackaddr(&attr, (void **)bottom) != 0 ||
    pthread_attr_getstacksize(&attr, size) != 0) {
    fatal("Can not locate current stack attributes!");
  }

  pthread_attr_destroy(&attr);
#endif
  assert(os::current_stack_pointer() >= *bottom &&
         os::current_stack_pointer() < *bottom + *size, "just checking");
}

address os::current_stack_base() {
  address bottom;
  size_t size;
  current_stack_region(&bottom, &size);
  return (bottom + size);
}

size_t os::current_stack_size() {
  // stack size includes normal stack and HotSpot guard pages
  address bottom;
  size_t size;
  current_stack_region(&bottom, &size);
  return size;
}

/////////////////////////////////////////////////////////////////////////////
// helper functions for fatal error handler

void os::print_context(outputStream *st, const void *context) {
  if (context == NULL) return;

  const ucontext_t *uc = (const ucontext_t*)context;

  st->print_cr("Registers:");
  st->print( " x0=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 0]);
  st->print(" x1=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 1]);
  st->print(" x2=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 2]);
  st->print(" x3=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 3]);
  st->cr();
  st->print( " x4=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 4]);
  st->print(" x5=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 5]);
  st->print(" x6=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 6]);
  st->print(" x7=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 7]);
  st->cr();
  st->print( " x8=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 8]);
  st->print(" x9=" INTPTR_FORMAT, (intptr_t)uc->context_x[ 9]);
  st->print(" x10=" INTPTR_FORMAT, (intptr_t)uc->context_x[10]);
  st->print(" x11=" INTPTR_FORMAT, (intptr_t)uc->context_x[11]);
  st->cr();
  st->print( "x12=" INTPTR_FORMAT, (intptr_t)uc->context_x[12]);
  st->print(" x13=" INTPTR_FORMAT, (intptr_t)uc->context_x[13]);
  st->print(" x14=" INTPTR_FORMAT, (intptr_t)uc->context_x[14]);
  st->print(" x15=" INTPTR_FORMAT, (intptr_t)uc->context_x[15]);
  st->cr();
  st->print( "x16=" INTPTR_FORMAT, (intptr_t)uc->context_x[16]);
  st->print(" x17=" INTPTR_FORMAT, (intptr_t)uc->context_x[17]);
  st->print(" x18=" INTPTR_FORMAT, (intptr_t)uc->context_x[18]);
  st->print(" x19=" INTPTR_FORMAT, (intptr_t)uc->context_x[19]);
  st->cr();
  st->print( "x20=" INTPTR_FORMAT, (intptr_t)uc->context_x[20]);
  st->print(" x21=" INTPTR_FORMAT, (intptr_t)uc->context_x[21]);
  st->print(" x22=" INTPTR_FORMAT, (intptr_t)uc->context_x[22]);
  st->print(" x23=" INTPTR_FORMAT, (intptr_t)uc->context_x[23]);
  st->cr();
  st->print( "x24=" INTPTR_FORMAT, (intptr_t)uc->context_x[24]);
  st->print(" x25=" INTPTR_FORMAT, (intptr_t)uc->context_x[25]);
  st->print(" x26=" INTPTR_FORMAT, (intptr_t)uc->context_x[26]);
  st->print(" x27=" INTPTR_FORMAT, (intptr_t)uc->context_x[27]);
  st->cr();
  st->print( "x28=" INTPTR_FORMAT, (intptr_t)uc->context_x[28]);
  st->print(" fp=" INTPTR_FORMAT, (intptr_t)uc->context_fp);
  st->print(" lr=" INTPTR_FORMAT, (intptr_t)uc->context_lr);
  st->print(" sp=" INTPTR_FORMAT, (intptr_t)uc->context_sp);
  st->cr();
  st->print(  "pc=" INTPTR_FORMAT,  (intptr_t)uc->context_pc);
  st->print(" cpsr=" INTPTR_FORMAT, (intptr_t)uc->context_cpsr);
  st->cr();
}

void os::print_tos_pc(outputStream *st, const void *context) {
  if (context == NULL) return;

  const ucontext_t* uc = (const ucontext_t*)context;

  address sp = (address)os::Bsd::ucontext_get_sp(uc);
  print_tos(st, sp);
  st->cr();

  // Note: it may be unsafe to inspect memory near pc. For example, pc may
  // point to garbage if entry point in an nmethod is corrupted. Leave
  // this at the end, and hope for the best.
  address pc = os::Posix::ucontext_get_pc(uc);
  print_instructions(st, pc, 4/*native instruction size*/);
  st->cr();
}

void os::print_register_info(outputStream *st, const void *context) {
  if (context == NULL) return;

  const ucontext_t *uc = (const ucontext_t*)context;

  st->print_cr("Register to memory mapping:");
  st->cr();

  // this is horrendously verbose but the layout of the registers in the
  // context does not match how we defined our abstract Register set, so
  // we can't just iterate through the gregs area

  // this is only for the "general purpose" registers

  st->print(" x0="); print_location(st, uc->context_x[ 0]);
  st->print(" x1="); print_location(st, uc->context_x[ 1]);
  st->print(" x2="); print_location(st, uc->context_x[ 2]);
  st->print(" x3="); print_location(st, uc->context_x[ 3]);
  st->print(" x4="); print_location(st, uc->context_x[ 4]);
  st->print(" x5="); print_location(st, uc->context_x[ 5]);
  st->print(" x6="); print_location(st, uc->context_x[ 6]);
  st->print(" x7="); print_location(st, uc->context_x[ 7]);
  st->print(" x8="); print_location(st, uc->context_x[ 8]);
  st->print(" x9="); print_location(st, uc->context_x[ 9]);
  st->print("x10="); print_location(st, uc->context_x[10]);
  st->print("x11="); print_location(st, uc->context_x[11]);
  st->print("x12="); print_location(st, uc->context_x[12]);
  st->print("x13="); print_location(st, uc->context_x[13]);
  st->print("x14="); print_location(st, uc->context_x[14]);
  st->print("x15="); print_location(st, uc->context_x[15]);
  st->print("x16="); print_location(st, uc->context_x[16]);
  st->print("x17="); print_location(st, uc->context_x[17]);
  st->print("x18="); print_location(st, uc->context_x[18]);
  st->print("x19="); print_location(st, uc->context_x[19]);
  st->print("x20="); print_location(st, uc->context_x[20]);
  st->print("x21="); print_location(st, uc->context_x[21]);
  st->print("x22="); print_location(st, uc->context_x[22]);
  st->print("x23="); print_location(st, uc->context_x[23]);
  st->print("x24="); print_location(st, uc->context_x[24]);
  st->print("x25="); print_location(st, uc->context_x[25]);
  st->print("x26="); print_location(st, uc->context_x[26]);
  st->print("x27="); print_location(st, uc->context_x[27]);
  st->print("x28="); print_location(st, uc->context_x[28]);

  st->cr();
}

void os::setup_fpu() {
}

#ifndef PRODUCT
void os::verify_stack_alignment() {
  assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
}
#endif

int os::extra_bang_size_in_bytes() {
  // AArch64 does not require the additional stack bang.
  return 0;
}

void os::current_thread_enable_wx(WXMode mode) {
  pthread_jit_write_protect_np(mode == WXExec);
}

static inline void atomic_copy64(const volatile void *src, volatile void *dst) {
  *(jlong *) dst = *(const jlong *) src;
}

extern "C" {
  int SpinPause() {
    return 0;
  }

  void _Copy_conjoint_jshorts_atomic(const jshort* from, jshort* to, size_t count) {
    if (from > to) {
      const jshort *end = from + count;
      while (from < end)
        *(to++) = *(from++);
    }
    else if (from < to) {
      const jshort *end = from;
      from += count - 1;
      to   += count - 1;
      while (from >= end)
        *(to--) = *(from--);
    }
  }
  void _Copy_conjoint_jints_atomic(const jint* from, jint* to, size_t count) {
    if (from > to) {
      const jint *end = from + count;
      while (from < end)
        *(to++) = *(from++);
    }
    else if (from < to) {
      const jint *end = from;
      from += count - 1;
      to   += count - 1;
      while (from >= end)
        *(to--) = *(from--);
    }
  }

  void _Copy_conjoint_jlongs_atomic(const jlong* from, jlong* to, size_t count) {
    if (from > to) {
      const jlong *end = from + count;
      while (from < end)
        atomic_copy64(from++, to++);
    }
    else if (from < to) {
      const jlong *end = from;
      from += count - 1;
      to   += count - 1;
      while (from >= end)
        atomic_copy64(from--, to--);
    }
  }

  void _Copy_arrayof_conjoint_bytes(const HeapWord* from,
                                    HeapWord* to,
                                    size_t    count) {
    memmove(to, from, count);
  }
  void _Copy_arrayof_conjoint_jshorts(const HeapWord* from,
                                      HeapWord* to,
                                      size_t    count) {
    memmove(to, from, count * 2);
  }
  void _Copy_arrayof_conjoint_jints(const HeapWord* from,
                                    HeapWord* to,
                                    size_t    count) {
    memmove(to, from, count * 4);
  }
  void _Copy_arrayof_conjoint_jlongs(const HeapWord* from,
                                     HeapWord* to,
                                     size_t    count) {
    memmove(to, from, count * 8);
  }
};

quality94%

¤ Dauer der Verarbeitung: 0.14 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.