/*

 * 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 "jvm.h"

#include "asm/macroAssembler.inline.hpp"

#include "memory/resourceArea.hpp"

#include "runtime/java.hpp"

#include "runtime/os.inline.hpp"

#include "runtime/stubCodeGenerator.hpp"

int  VM_Version::_stored_pc_adjustment = 4;

int  VM_Version::_arm_arch             = 5;

bool VM_Version::_is_initialized       = false;

int VM_Version::_kuser_helper_version  = 0;

extern "C" {

  typedef int (*get_cpu_info_t)();

  typedef bool (*check_vfp_t)(double *d);

  typedef bool (*check_simd_t)();

  typedef bool (*check_mp_ext_t)(int *addr);

}

#define __ _masm->

class VM_Version_StubGenerator: public StubCodeGenerator {

 public:

  VM_Version_StubGenerator(CodeBuffer *c) : StubCodeGenerator(c) {}

  address generate_get_cpu_info() {

    StubCodeMark mark(this, "VM_Version", "get_cpu_info");

    address start = __ pc();

    __ mov(R0, PC);

    __ push(PC);

    __ pop(R1);

    __ sub(R0, R1, R0);

    // return the result in R0

    __ bx(LR);

    return start;

  };

  address generate_check_vfp() {

    StubCodeMark mark(this, "VM_Version", "check_vfp");

    address start = __ pc();

    __ fstd(D0, Address(R0));

    __ mov(R0, 1);

    __ bx(LR);

    return start;

  };

  address generate_check_vfp3_32() {

    StubCodeMark mark(this, "VM_Version", "check_vfp3_32");

    address start = __ pc();

    __ fstd(D16, Address(R0));

    __ mov(R0, 1);

    __ bx(LR);

    return start;

  };

  address generate_check_simd() {

    StubCodeMark mark(this, "VM_Version", "check_simd");

    address start = __ pc();

    __ vcnt(Stemp, Stemp);

    __ mov(R0, 1);

    __ bx(LR);

    return start;

  };

  address generate_check_mp_ext() {

    StubCodeMark mark(this, "VM_Version", "check_mp_ext");

    address start = __ pc();

    // PLDW is available with Multiprocessing Extensions only

    __ pldw(Address(R0));

    // Return true if instruction caused no signals

    __ mov(R0, 1);

    // JVM_handle_linux_signal moves PC here if SIGILL happens

    __ bx(LR);

    return start;

  };

};

#undef __

extern "C" address check_vfp3_32_fault_instr;

extern "C" address check_vfp_fault_instr;

extern "C" address check_simd_fault_instr;

extern "C" address check_mp_ext_fault_instr;

void VM_Version::early_initialize() {

  // Make sure that _arm_arch is initialized so that any calls to OrderAccess will

  // use proper dmb instruction

  get_os_cpu_info();

  _kuser_helper_version = *(int*)KUSER_HELPER_VERSION_ADDR;

  // armv7 has the ldrexd instruction that can be used to implement cx8

  // armv5 with linux >= 3.1 can use kernel helper routine

  _supports_cx8 = (supports_ldrexd() || supports_kuser_cmpxchg64());

}

void VM_Version::initialize() {

  ResourceMark rm;

  // Making this stub must be FIRST use of assembler

  const int stub_size = 128;

  BufferBlob* stub_blob = BufferBlob::create("get_cpu_info", stub_size);

  if (stub_blob == NULL) {

    vm_exit_during_initialization("Unable to allocate get_cpu_info stub");

  }

  CodeBuffer c(stub_blob);

  VM_Version_StubGenerator g(&c);

  address get_cpu_info_pc = g.generate_get_cpu_info();

  get_cpu_info_t get_cpu_info = CAST_TO_FN_PTR(get_cpu_info_t, get_cpu_info_pc);

  int pc_adjustment = get_cpu_info();

  VM_Version::_stored_pc_adjustment = pc_adjustment;

#ifndef __SOFTFP__

  address check_vfp_pc = g.generate_check_vfp();

  check_vfp_t check_vfp = CAST_TO_FN_PTR(check_vfp_t, check_vfp_pc);

  check_vfp_fault_instr = (address)check_vfp;

  double dummy;

  if (check_vfp(&dummy)) {

    _features |= vfp_m;

  }

#ifdef COMPILER2

  if (has_vfp()) {

    address check_vfp3_32_pc = g.generate_check_vfp3_32();

    check_vfp_t check_vfp3_32 = CAST_TO_FN_PTR(check_vfp_t, check_vfp3_32_pc);

    check_vfp3_32_fault_instr = (address)check_vfp3_32;

    double dummy;

    if (check_vfp3_32(&dummy)) {

      _features |= vfp3_32_m;

    }

    address check_simd_pc =g.generate_check_simd();

    check_simd_t check_simd = CAST_TO_FN_PTR(check_simd_t, check_simd_pc);

    check_simd_fault_instr = (address)check_simd;

    if (check_simd()) {

      _features |= simd_m;

    }

  }

#endif

#endif

  address check_mp_ext_pc = g.generate_check_mp_ext();

  check_mp_ext_t check_mp_ext = CAST_TO_FN_PTR(check_mp_ext_t, check_mp_ext_pc);

  check_mp_ext_fault_instr = (address)check_mp_ext;

  int dummy_local_variable;

  if (check_mp_ext(&dummy_local_variable)) {

    _features |= mp_ext_m;

  }

  if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {

    warning("AES intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseAESIntrinsics, false);

  }

  if (UseAES && !FLAG_IS_DEFAULT(UseAES)) {

    warning("AES instructions are not available on this CPU");

    FLAG_SET_DEFAULT(UseAES, false);

  }

  if (UseAESCTRIntrinsics) {

    warning("AES/CTR intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseAESCTRIntrinsics, false);

  }

  if (UseFMA) {

    warning("FMA instructions are not available on this CPU");

    FLAG_SET_DEFAULT(UseFMA, false);

  }

  if (UseSHA) {

    warning("SHA instructions are not available on this CPU");

    FLAG_SET_DEFAULT(UseSHA, false);

  }

  if (UseSHA1Intrinsics) {

    warning("Intrinsics for SHA-1 crypto hash functions not available on this CPU.");

    FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);

  }

  if (UseSHA256Intrinsics) {

    warning("Intrinsics for SHA-224 and SHA-256 crypto hash functions not available on this CPU.");

    FLAG_SET_DEFAULT(UseSHA256Intrinsics, false);

  }

  if (UseSHA512Intrinsics) {

    warning("Intrinsics for SHA-384 and SHA-512 crypto hash functions not available on this CPU.");

    FLAG_SET_DEFAULT(UseSHA512Intrinsics, false);

  }

  if (UseCRC32Intrinsics) {

    if (!FLAG_IS_DEFAULT(UseCRC32Intrinsics))

      warning("CRC32 intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseCRC32Intrinsics, false);

  }

  if (UseCRC32CIntrinsics) {

    if (!FLAG_IS_DEFAULT(UseCRC32CIntrinsics))

      warning("CRC32C intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);

  }

  if (UseAdler32Intrinsics) {

    warning("Adler32 intrinsics are not available on this CPU");

    FLAG_SET_DEFAULT(UseAdler32Intrinsics, false);

  }

  if (UseVectorizedMismatchIntrinsic) {

    warning("vectorizedMismatch intrinsic is not available on this CPU.");

    FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false);

  }

#ifdef COMPILER2

  // C2 is only supported on v7+ VFP at this time

  if (_arm_arch < 7 || !has_vfp()) {

    vm_exit_during_initialization("Server VM is only supported on ARMv7+ VFP");

  }

#endif

  // ARM doesn't have special instructions for these but ldrex/ldrexd

  // enable shorter instruction sequences that the ones based on cas.

  _supports_atomic_getset4 = supports_ldrex();

  _supports_atomic_getadd4 = supports_ldrex();

  _supports_atomic_getset8 = supports_ldrexd();

  _supports_atomic_getadd8 = supports_ldrexd();

#ifdef COMPILER2

  assert(_supports_cx8 && _supports_atomic_getset4 && _supports_atomic_getadd4

         && _supports_atomic_getset8 && _supports_atomic_getadd8, "C2: atomic operations must be supported");

#endif

  char buf[512];

  jio_snprintf(buf, sizeof(buf), "(ARMv%d)%s%s%s%s",

               _arm_arch,

               (has_vfp() ? ", vfp" : ""),

               (has_vfp3_32() ? ", vfp3-32" : ""),

               (has_simd() ? ", simd" : ""),

               (has_multiprocessing_extensions() ? ", mp_ext" : ""));

  // buf is started with ", " or is empty

  _features_string = os::strdup(buf);

  if (has_simd()) {

    if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {

      FLAG_SET_DEFAULT(UsePopCountInstruction, true);

    }

  } else {

    FLAG_SET_DEFAULT(UsePopCountInstruction, false);

  }

  if (FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {

    FLAG_SET_DEFAULT(AllocatePrefetchDistance, 128);

  }

#ifdef COMPILER2

  FLAG_SET_DEFAULT(UseFPUForSpilling, true);

  if (FLAG_IS_DEFAULT(MaxVectorSize)) {

    // FLAG_SET_DEFAULT(MaxVectorSize, has_simd() ? 16 : 8);

    // SIMD/NEON can use 16, but default is 8 because currently

    // larger than 8 will disable instruction scheduling

    FLAG_SET_DEFAULT(MaxVectorSize, 8);

  } else {

    int max_vector_size = has_simd() ? 16 : 8;

    if (MaxVectorSize > max_vector_size) {

      warning("MaxVectorSize must be at most %i on this platform", max_vector_size);

      FLAG_SET_DEFAULT(MaxVectorSize, max_vector_size);

    }

  }

#endif

  if (FLAG_IS_DEFAULT(Tier4CompileThreshold)) {

    Tier4CompileThreshold = 10000;

  }

  if (FLAG_IS_DEFAULT(Tier3InvocationThreshold)) {

    Tier3InvocationThreshold = 1000;

  }

  if (FLAG_IS_DEFAULT(Tier3CompileThreshold)) {

    Tier3CompileThreshold = 5000;

  }

  if (FLAG_IS_DEFAULT(Tier3MinInvocationThreshold)) {

    Tier3MinInvocationThreshold = 500;

  }

  UNSUPPORTED_OPTION(TypeProfileLevel);

  UNSUPPORTED_OPTION(CriticalJNINatives);

  FLAG_SET_DEFAULT(TypeProfileLevel, 0); // unsupported

  // This machine does not allow unaligned memory accesses

  if (UseUnalignedAccesses) {

    if (!FLAG_IS_DEFAULT(UseUnalignedAccesses))

      warning("Unaligned memory access is not available on this CPU");

    FLAG_SET_DEFAULT(UseUnalignedAccesses, false);

  }

  _is_initialized = true;

}

bool VM_Version::use_biased_locking() {

  get_os_cpu_info();

  // The cost of CAS on uniprocessor ARM v6 and later is low compared to the

  // overhead related to slightly longer Biased Locking execution path.

  // Testing shows no improvement when running with Biased Locking enabled

  // on an ARMv6 and higher uniprocessor systems.  The situation is different on

  // ARMv5 and MP systems.

  //

  // Therefore the Biased Locking is enabled on ARMv5 and ARM MP only.

  //

  return (!os::is_MP() && (arm_arch() > 5)) ? false : true;

}