* Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.

 * Copyright (c) 2012, 2019 SAP SE. All rights reserved.

#include "asm/macroAssembler.inline.hpp"

#include "gc/shared/barrierSet.hpp"

#include "gc/shared/barrierSetAssembler.hpp"

#define __ masm->

#define BUFFER_SIZE 48*BytesPerInstWord

// Common register usage:

// R3/F0:      result

// R3_ARG1:    jni env

// R4_ARG2:    obj

// R5_ARG3:    jfield id

  const char *name;

  switch (type) {

    case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break;

    case T_BYTE:    name = "jni_fast_GetByteField";    break;

    case T_CHAR:    name = "jni_fast_GetCharField";    break;

    case T_SHORT:   name = "jni_fast_GetShortField";   break;

    case T_INT:     name = "jni_fast_GetIntField";     break;

    case T_LONG:    name = "jni_fast_GetLongField";    break;

    case T_FLOAT:   name = "jni_fast_GetFloatField";   break;

    case T_DOUBLE:  name = "jni_fast_GetDoubleField";  break;

    default:        ShouldNotReachHere();

      name = NULL;  // unreachable

  }

  ResourceMark rm;

  BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);

  CodeBuffer cbuf(blob);

  MacroAssembler* masm = new MacroAssembler(&cbuf);

  address fast_entry = __ function_entry();

  Label slow;

  const Register Rcounter_addr = R6_ARG4,

                 Rcounter      = R7_ARG5,

                 Robj          = R8_ARG6,

                 Rtmp          = R9_ARG7;

  const int counter_offs = __ load_const_optimized(Rcounter_addr,

                                                   SafepointSynchronize::safepoint_counter_addr(),

                                                   R0, true);

  __ ld(Rcounter, counter_offs, Rcounter_addr);

  __ andi_(R0, Rcounter, 1);

  __ bne(CCR0, slow);

  if (support_IRIW_for_not_multiple_copy_atomic_cpu) {

    // Field may be volatile.

    __ fence();

  } else {

    // Using acquire to order wrt. JVMTI check and load of result.

    __ isync(); // order wrt. to following load(s)

  }

  if (JvmtiExport::can_post_field_access()) {

    // Check to see if a field access watch has been set before we

    // take the fast path.

    int fac_offs = __ load_const_optimized(Rtmp, JvmtiExport::get_field_access_count_addr(),

                                           R0, true);

    __ lwa(Rtmp, fac_offs, Rtmp);

    __ cmpwi(CCR0, Rtmp, 0);

    __ bne(CCR0, slow);

  }

  BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();

  bs->try_resolve_jobject_in_native(masm, Robj, R3_ARG1, R4_ARG2, Rtmp, slow);

  __ srwi(Rtmp, R5_ARG3, 2); // offset

  assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");

  speculative_load_pclist[count] = __ pc();   // Used by the segfault handler

  bool is_fp = false;

  switch (type) {

    case T_BOOLEAN: __ lbzx(Rtmp, Rtmp, Robj); break;

    case T_BYTE:    __ lbzx(Rtmp, Rtmp, Robj); __ extsb(Rtmp, Rtmp); break;

    case T_CHAR:    __ lhzx(Rtmp, Rtmp, Robj); break;

    case T_SHORT:   __ lhax(Rtmp, Rtmp, Robj); break;

    case T_INT:     __ lwax(Rtmp, Rtmp, Robj); break;

    case T_LONG:    __ ldx( Rtmp, Rtmp, Robj); break;

    case T_FLOAT:   __ lfsx(F1_RET, Rtmp, Robj); is_fp = true; break;

    case T_DOUBLE:  __ lfdx(F1_RET, Rtmp, Robj); is_fp = true; break;

    default:        ShouldNotReachHere();

  }

  // Order preceding load(s) wrt. succeeding check (LoadStore for volatile field).

  if (is_fp) {

    Label next;

    __ fcmpu(CCR0, F1_RET, F1_RET);

    __ bne(CCR0, next);

    __ bind(next);

  } else {

    __ twi_0(Rtmp);

  }

  __ isync();

  __ ld(R0, counter_offs, Rcounter_addr);

  __ cmpd(CCR0, R0, Rcounter);

  __ bne(CCR0, slow);

  if (!is_fp) {

    __ mr(R3_RET, Rtmp);

  }

  __ blr();

  slowcase_entry_pclist[count++] = __ pc();

  __ bind(slow);

  address slow_case_addr;

  switch (type) {

    case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break;

    case T_BYTE:    slow_case_addr = jni_GetByteField_addr();    break;

    case T_CHAR:    slow_case_addr = jni_GetCharField_addr();    break;

    case T_SHORT:   slow_case_addr = jni_GetShortField_addr();   break;

    case T_INT:     slow_case_addr = jni_GetIntField_addr();     break;

    case T_LONG:    slow_case_addr = jni_GetLongField_addr();    break;

    case T_FLOAT:   slow_case_addr = jni_GetFloatField_addr();   break;

    case T_DOUBLE:  slow_case_addr = jni_GetDoubleField_addr();  break;

    default:        ShouldNotReachHere();

      slow_case_addr = NULL;  // unreachable

  }

  __ load_const_optimized(R12, slow_case_addr, R0);

  __ call_c_and_return_to_caller(R12); // tail call

  __ flush();

  return fast_entry;

  return generate_fast_get_int_field0(T_LONG);

  return generate_fast_get_int_field0(T_FLOAT);

  return generate_fast_get_int_field0(T_DOUBLE);