1 /*
   2  * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/macroAssembler.hpp"
  27 #include "gc/shared/barrierSet.hpp"
  28 #include "gc/shared/barrierSetAssembler.hpp"
  29 #include "memory/resourceArea.hpp"
  30 #include "prims/jniFastGetField.hpp"
  31 #include "prims/jvm_misc.hpp"
  32 #include "runtime/safepoint.hpp"
  33 
  34 #define __ masm->
  35 
  36 #define BUFFER_SIZE 30*wordSize
  37 
  38 // Common register usage:
  39 // rax/xmm0: result
  40 // c_rarg0:    jni env
  41 // c_rarg1:    obj
  42 // c_rarg2:    jfield id
  43 
  44 static const Register rtmp     = rax; // r8 == c_rarg2 on Windows
  45 static const Register robj     = r9;
  46 static const Register roffset  = r10;
  47 static const Register rcounter = r11;
  48 
  49 // Warning: do not use rip relative addressing after the first counter load
  50 // since that may scratch r10!
  51 
  52 address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) {
  53   const char *name = NULL;
  54   switch (type) {
  55     case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break;
  56     case T_BYTE:    name = "jni_fast_GetByteField";    break;
  57     case T_CHAR:    name = "jni_fast_GetCharField";    break;
  58     case T_SHORT:   name = "jni_fast_GetShortField";   break;
  59     case T_INT:     name = "jni_fast_GetIntField";     break;
  60     case T_LONG:    name = "jni_fast_GetLongField";    break;
  61     default:        ShouldNotReachHere();
  62   }
  63   ResourceMark rm;
  64   BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
  65   CodeBuffer cbuf(blob);
  66   MacroAssembler* masm = new MacroAssembler(&cbuf);
  67   address fast_entry = __ pc();
  68 
  69   Label slow;
  70 
  71   ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
  72   __ mov32 (rcounter, counter);
  73   __ mov   (robj, c_rarg1);
  74   __ testb (rcounter, 1);
  75   __ jcc (Assembler::notZero, slow);
  76 
  77   if (JvmtiExport::can_post_field_access()) {
  78     // Check to see if a field access watch has been set before we
  79     // take the fast path.
  80     assert_different_registers(rscratch1, robj, rcounter); // cmp32 clobbers rscratch1!
  81     __ cmp32(ExternalAddress((address) JvmtiExport::get_field_access_count_addr()), 0);
  82     __ jcc(Assembler::notZero, slow);
  83   }
  84 
  85   __ mov   (roffset, c_rarg2);
  86   __ shrptr(roffset, 2);                         // offset
  87 
  88   // Both robj and rtmp are clobbered by try_resolve_jobject_in_native.
  89   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
  90   bs->try_resolve_jobject_in_native(masm, /* jni_env */ c_rarg0, robj, rtmp, slow);
  91   DEBUG_ONLY(__ movl(rtmp, 0xDEADC0DE);)
  92 
  93   assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
  94   speculative_load_pclist[count] = __ pc();
  95   switch (type) {
  96     case T_BOOLEAN: __ movzbl (rax, Address(robj, roffset, Address::times_1)); break;
  97     case T_BYTE:    __ movsbl (rax, Address(robj, roffset, Address::times_1)); break;
  98     case T_CHAR:    __ movzwl (rax, Address(robj, roffset, Address::times_1)); break;
  99     case T_SHORT:   __ movswl (rax, Address(robj, roffset, Address::times_1)); break;
 100     case T_INT:     __ movl   (rax, Address(robj, roffset, Address::times_1)); break;
 101     case T_LONG:    __ movq   (rax, Address(robj, roffset, Address::times_1)); break;
 102     default:        ShouldNotReachHere();
 103   }
 104 
 105   __ cmp32 (rcounter, counter);
 106   __ jcc (Assembler::notEqual, slow);
 107 
 108   __ ret (0);
 109 
 110   slowcase_entry_pclist[count++] = __ pc();
 111   __ bind (slow);
 112   address slow_case_addr = NULL;
 113   switch (type) {
 114     case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break;
 115     case T_BYTE:    slow_case_addr = jni_GetByteField_addr();    break;
 116     case T_CHAR:    slow_case_addr = jni_GetCharField_addr();    break;
 117     case T_SHORT:   slow_case_addr = jni_GetShortField_addr();   break;
 118     case T_INT:     slow_case_addr = jni_GetIntField_addr();     break;
 119     case T_LONG:    slow_case_addr = jni_GetLongField_addr();    break;
 120     default:                                                     break;
 121   }
 122   // tail call
 123   __ jump (ExternalAddress(slow_case_addr));
 124 
 125   __ flush ();
 126 
 127   return fast_entry;
 128 }
 129 
 130 address JNI_FastGetField::generate_fast_get_boolean_field() {
 131   return generate_fast_get_int_field0(T_BOOLEAN);
 132 }
 133 
 134 address JNI_FastGetField::generate_fast_get_byte_field() {
 135   return generate_fast_get_int_field0(T_BYTE);
 136 }
 137 
 138 address JNI_FastGetField::generate_fast_get_char_field() {
 139   return generate_fast_get_int_field0(T_CHAR);
 140 }
 141 
 142 address JNI_FastGetField::generate_fast_get_short_field() {
 143   return generate_fast_get_int_field0(T_SHORT);
 144 }
 145 
 146 address JNI_FastGetField::generate_fast_get_int_field() {
 147   return generate_fast_get_int_field0(T_INT);
 148 }
 149 
 150 address JNI_FastGetField::generate_fast_get_long_field() {
 151   return generate_fast_get_int_field0(T_LONG);
 152 }
 153 
 154 address JNI_FastGetField::generate_fast_get_float_field0(BasicType type) {
 155   const char *name = NULL;
 156   switch (type) {
 157     case T_FLOAT:     name = "jni_fast_GetFloatField";     break;
 158     case T_DOUBLE:    name = "jni_fast_GetDoubleField";    break;
 159     default:          ShouldNotReachHere();
 160   }
 161   ResourceMark rm;
 162   BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
 163   CodeBuffer cbuf(blob);
 164   MacroAssembler* masm = new MacroAssembler(&cbuf);
 165   address fast_entry = __ pc();
 166 
 167   Label slow;
 168 
 169   ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
 170   __ mov32 (rcounter, counter);
 171   __ mov   (robj, c_rarg1);
 172   __ testb (rcounter, 1);
 173   __ jcc (Assembler::notZero, slow);
 174 
 175   if (JvmtiExport::can_post_field_access()) {
 176     // Check to see if a field access watch has been set before we
 177     // take the fast path.
 178     __ cmp32(ExternalAddress((address) JvmtiExport::get_field_access_count_addr()), 0);
 179     __ jcc(Assembler::notZero, slow);
 180   }
 181 
 182   // Both robj and rtmp are clobbered by try_resolve_jobject_in_native.
 183   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
 184   bs->try_resolve_jobject_in_native(masm, /* jni_env */ c_rarg0, robj, rtmp, slow);
 185   DEBUG_ONLY(__ movl(rtmp, 0xDEADC0DE);)
 186 
 187   __ mov   (roffset, c_rarg2);
 188   __ shrptr(roffset, 2);                         // offset
 189 
 190   assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
 191   speculative_load_pclist[count] = __ pc();
 192   switch (type) {
 193     case T_FLOAT:  __ movflt (xmm0, Address(robj, roffset, Address::times_1)); break;
 194     case T_DOUBLE: __ movdbl (xmm0, Address(robj, roffset, Address::times_1)); break;
 195     default:        ShouldNotReachHere();
 196   }
 197   __ cmp32 (rcounter, counter);
 198   __ jcc (Assembler::notEqual, slow);
 199 
 200   __ ret (0);
 201 
 202   slowcase_entry_pclist[count++] = __ pc();
 203   __ bind (slow);
 204   address slow_case_addr = NULL;
 205   switch (type) {
 206     case T_FLOAT:     slow_case_addr = jni_GetFloatField_addr();  break;
 207     case T_DOUBLE:    slow_case_addr = jni_GetDoubleField_addr(); break;
 208     default:                                                      break;
 209   }
 210   // tail call
 211   __ jump (ExternalAddress(slow_case_addr));
 212 
 213   __ flush ();
 214 
 215   return fast_entry;
 216 }
 217 
 218 address JNI_FastGetField::generate_fast_get_float_field() {
 219   return generate_fast_get_float_field0(T_FLOAT);
 220 }
 221 
 222 address JNI_FastGetField::generate_fast_get_double_field() {
 223   return generate_fast_get_float_field0(T_DOUBLE);
 224 }