6939861: JVM should handle more conversion operations

Reviewed-by: twisti, jrose

1 files changed, 292 insertions, 0 deletions

diff --git a/src/cpu/x86/vm/methodHandles_x86.hpp b/src/cpu/x86/vm/methodHandles_x86.hpp
new file mode 100644
index 000000000..2a93500d7
--- /dev/null
+++ b/src/cpu/x86/vm/methodHandles_x86.hpp
@@ -0,0 +1,292 @@
+/*
+ * Copyright (c) 2010, 2011, 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.
+ *
+ */
+
+// Platform-specific definitions for method handles.
+// These definitions are inlined into class MethodHandles.
+
+public:
+
+// The stack just after the recursive call from a ricochet frame
+// looks something like this.  Offsets are marked in words, not bytes.
+// rsi (r13 on LP64) is part of the interpreter calling sequence
+// which tells the callee where is my real rsp (for frame walking).
+// (...lower memory addresses)
+// rsp:     [ return pc                 ]   always the global RicochetBlob::bounce_addr
+// rsp+1:   [ recursive arg N           ]
+// rsp+2:   [ recursive arg N-1         ]
+// ...
+// rsp+N:   [ recursive arg 1           ]
+// rsp+N+1: [ recursive method handle   ]
+// ...
+// rbp-6:   [ cleanup continuation pc   ]   <-- (struct RicochetFrame)
+// rbp-5:   [ saved target MH           ]   the MH we will call on the saved args
+// rbp-4:   [ saved args layout oop     ]   an int[] array which describes argument layout
+// rbp-3:   [ saved args pointer        ]   address of transformed adapter arg M (slot 0)
+// rbp-2:   [ conversion                ]   information about how the return value is used
+// rbp-1:   [ exact sender sp           ]   exact TOS (rsi/r13) of original sender frame
+// rbp+0:   [ saved sender fp           ]   (for original sender of AMH)
+// rbp+1:   [ saved sender pc           ]   (back to original sender of AMH)
+// rbp+2:   [ transformed adapter arg M ]   <-- (extended TOS of original sender)
+// rbp+3:   [ transformed adapter arg M-1]
+// ...
+// rbp+M+1: [ transformed adapter arg 1 ]
+// rbp+M+2: [ padding                   ] <-- (rbp + saved args base offset)
+// ...      [ optional padding]
+// (higher memory addresses...)
+//
+// The arguments originally passed by the original sender
+// are lost, and arbitrary amounts of stack motion might have
+// happened due to argument transformation.
+// (This is done by C2I/I2C adapters and non-direct method handles.)
+// This is why there is an unpredictable amount of memory between
+// the extended and exact TOS of the sender.
+// The ricochet adapter itself will also (in general) perform
+// transformations before the recursive call.
+//
+// The transformed and saved arguments, immediately above the saved
+// return PC, are a well-formed method handle invocation ready to execute.
+// When the GC needs to walk the stack, these arguments are described
+// via the saved arg types oop, an int[] array with a private format.
+// This array is derived from the type of the transformed adapter
+// method handle, which also sits at the base of the saved argument
+// bundle.  Since the GC may not be able to fish out the int[]
+// array, so it is pushed explicitly on the stack.  This may be
+// an unnecessary expense.
+//
+// The following register conventions are significant at this point:
+// rsp       the thread stack, as always; preserved by caller
+// rsi/r13   exact TOS of recursive frame (contents of [rbp-2])
+// rcx       recursive method handle (contents of [rsp+N+1])
+// rbp       preserved by caller (not used by caller)
+// Unless otherwise specified, all registers can be blown by the call.
+//
+// If this frame must be walked, the transformed adapter arguments
+// will be found with the help of the saved arguments descriptor.
+//
+// Therefore, the descriptor must match the referenced arguments.
+// The arguments must be followed by at least one word of padding,
+// which will be necessary to complete the final method handle call.
+// That word is not treated as holding an oop.  Neither is the word
+//
+// The word pointed to by the return argument pointer is not
+// treated as an oop, even if points to a saved argument.
+// This allows the saved argument list to have a "hole" in it
+// to receive an oop from the recursive call.
+// (The hole might temporarily contain RETURN_VALUE_PLACEHOLDER.)
+//
+// When the recursive callee returns, RicochetBlob::bounce_addr will
+// immediately jump to the continuation stored in the RF.
+// This continuation will merge the recursive return value
+// into the saved argument list.  At that point, the original
+// rsi, rbp, and rsp will be reloaded, the ricochet frame will
+// disappear, and the final target of the adapter method handle
+// will be invoked on the transformed argument list.
+
+class RicochetFrame {
+  friend class MethodHandles;
+
+ private:
+  intptr_t* _continuation;          // what to do when control gets back here
+  oopDesc*  _saved_target;          // target method handle to invoke on saved_args
+  oopDesc*  _saved_args_layout;     // caching point for MethodTypeForm.vmlayout cookie
+  intptr_t* _saved_args_base;       // base of pushed arguments (slot 0, arg N) (-3)
+  intptr_t  _conversion;            // misc. information from original AdapterMethodHandle (-2)
+  intptr_t* _exact_sender_sp;       // parallel to interpreter_frame_sender_sp (-1)
+  intptr_t* _sender_link;           // *must* coincide with frame::link_offset (0)
+  address   _sender_pc;             // *must* coincide with frame::return_addr_offset (1)
+
+ public:
+  intptr_t* continuation() const        { return _continuation; }
+  oop       saved_target() const        { return _saved_target; }
+  oop       saved_args_layout() const   { return _saved_args_layout; }
+  intptr_t* saved_args_base() const     { return _saved_args_base; }
+  intptr_t  conversion() const          { return _conversion; }
+  intptr_t* exact_sender_sp() const     { return _exact_sender_sp; }
+  intptr_t* sender_link() const         { return _sender_link; }
+  address   sender_pc() const           { return _sender_pc; }
+
+  intptr_t* extended_sender_sp() const  { return saved_args_base(); }
+
+  intptr_t  return_value_slot_number() const {
+    return adapter_conversion_vminfo(conversion());
+  }
+  BasicType return_value_type() const {
+    return adapter_conversion_dest_type(conversion());
+  }
+  bool has_return_value_slot() const {
+    return return_value_type() != T_VOID;
+  }
+  intptr_t* return_value_slot_addr() const {
+    assert(has_return_value_slot(), "");
+    return saved_arg_slot_addr(return_value_slot_number());
+  }
+  intptr_t* saved_target_slot_addr() const {
+    return saved_arg_slot_addr(saved_args_length());
+  }
+  intptr_t* saved_arg_slot_addr(int slot) const {
+    assert(slot >= 0, "");
+    return (intptr_t*)( (address)saved_args_base() + (slot * Interpreter::stackElementSize) );
+  }
+
+  jint      saved_args_length() const;
+  jint      saved_arg_offset(int arg) const;
+
+  // GC interface
+  oop*  saved_target_addr()                     { return (oop*)&_saved_target; }
+  oop*  saved_args_layout_addr()                { return (oop*)&_saved_args_layout; }
+
+  oop  compute_saved_args_layout(bool read_cache, bool write_cache);
+
+  // Compiler/assembler interface.
+  static int continuation_offset_in_bytes()     { return offset_of(RicochetFrame, _continuation); }
+  static int saved_target_offset_in_bytes()     { return offset_of(RicochetFrame, _saved_target); }
+  static int saved_args_layout_offset_in_bytes(){ return offset_of(RicochetFrame, _saved_args_layout); }
+  static int saved_args_base_offset_in_bytes()  { return offset_of(RicochetFrame, _saved_args_base); }
+  static int conversion_offset_in_bytes()       { return offset_of(RicochetFrame, _conversion); }
+  static int exact_sender_sp_offset_in_bytes()  { return offset_of(RicochetFrame, _exact_sender_sp); }
+  static int sender_link_offset_in_bytes()      { return offset_of(RicochetFrame, _sender_link); }
+  static int sender_pc_offset_in_bytes()        { return offset_of(RicochetFrame, _sender_pc); }
+
+  // This value is not used for much, but it apparently must be nonzero.
+  static int frame_size_in_bytes()              { return sender_link_offset_in_bytes(); }
+
+#ifdef ASSERT
+  // The magic number is supposed to help find ricochet frames within the bytes of stack dumps.
+  enum { MAGIC_NUMBER_1 = 0xFEED03E, MAGIC_NUMBER_2 = 0xBEEF03E };
+  static int magic_number_1_offset_in_bytes()   { return -wordSize; }
+  static int magic_number_2_offset_in_bytes()   { return sizeof(RicochetFrame); }
+  intptr_t magic_number_1() const               { return *(intptr_t*)((address)this + magic_number_1_offset_in_bytes()); };
+  intptr_t magic_number_2() const               { return *(intptr_t*)((address)this + magic_number_2_offset_in_bytes()); };
+#endif //ASSERT
+
+  enum { RETURN_VALUE_PLACEHOLDER = (NOT_DEBUG(0) DEBUG_ONLY(42)) };
+
+  static void verify_offsets() NOT_DEBUG_RETURN;
+  void verify() const NOT_DEBUG_RETURN; // check for MAGIC_NUMBER, etc.
+  void zap_arguments() NOT_DEBUG_RETURN;
+
+  static void generate_ricochet_blob(MacroAssembler* _masm,
+                                     // output params:
+                                     int* frame_size_in_words, int* bounce_offset, int* exception_offset);
+
+  static void enter_ricochet_frame(MacroAssembler* _masm,
+                                   Register rcx_recv,
+                                   Register rax_argv,
+                                   address return_handler,
+                                   Register rbx_temp);
+  static void leave_ricochet_frame(MacroAssembler* _masm,
+                                   Register rcx_recv,
+                                   Register new_sp_reg,
+                                   Register sender_pc_reg);
+
+  static Address frame_address(int offset = 0) {
+    // The RicochetFrame is found by subtracting a constant offset from rbp.
+    return Address(rbp, - sender_link_offset_in_bytes() + offset);
+  }
+
+  static RicochetFrame* from_frame(const frame& fr) {
+    address bp = (address) fr.fp();
+    RicochetFrame* rf = (RicochetFrame*)(bp - sender_link_offset_in_bytes());
+    rf->verify();
+    return rf;
+  }
+
+  static void verify_clean(MacroAssembler* _masm) NOT_DEBUG_RETURN;
+};
+
+// Additional helper methods for MethodHandles code generation:
+public:
+  static void load_klass_from_Class(MacroAssembler* _masm, Register klass_reg);
+  static void load_conversion_vminfo(MacroAssembler* _masm, Register reg, Address conversion_field_addr);
+  static void load_conversion_dest_type(MacroAssembler* _masm, Register reg, Address conversion_field_addr);
+
+  static void load_stack_move(MacroAssembler* _masm,
+                              Register rdi_stack_move,
+                              Register rcx_amh,
+                              bool might_be_negative);
+
+  static void insert_arg_slots(MacroAssembler* _masm,
+                               RegisterOrConstant arg_slots,
+                               Register rax_argslot,
+                               Register rbx_temp, Register rdx_temp);
+
+  static void remove_arg_slots(MacroAssembler* _masm,
+                               RegisterOrConstant arg_slots,
+                               Register rax_argslot,
+                               Register rbx_temp, Register rdx_temp);
+
+  static void push_arg_slots(MacroAssembler* _masm,
+                                   Register rax_argslot,
+                                   RegisterOrConstant slot_count,
+                                   int skip_words_count,
+                                   Register rbx_temp, Register rdx_temp);
+
+  static void move_arg_slots_up(MacroAssembler* _masm,
+                                Register rbx_bottom,  // invariant
+                                Address  top_addr,    // can use rax_temp
+                                RegisterOrConstant positive_distance_in_slots,
+                                Register rax_temp, Register rdx_temp);
+
+  static void move_arg_slots_down(MacroAssembler* _masm,
+                                  Address  bottom_addr,  // can use rax_temp
+                                  Register rbx_top,      // invariant
+                                  RegisterOrConstant negative_distance_in_slots,
+                                  Register rax_temp, Register rdx_temp);
+
+  static void move_typed_arg(MacroAssembler* _masm,
+                             BasicType type, bool is_element,
+                             Address slot_dest, Address value_src,
+                             Register rbx_temp, Register rdx_temp);
+
+  static void move_return_value(MacroAssembler* _masm, BasicType type,
+                                Address return_slot);
+
+  static void verify_argslot(MacroAssembler* _masm, Register argslot_reg,
+                             const char* error_message) NOT_DEBUG_RETURN;
+
+  static void verify_argslots(MacroAssembler* _masm,
+                              RegisterOrConstant argslot_count,
+                              Register argslot_reg,
+                              bool negate_argslot,
+                              const char* error_message) NOT_DEBUG_RETURN;
+
+  static void verify_stack_move(MacroAssembler* _masm,
+                                RegisterOrConstant arg_slots,
+                                int direction) NOT_DEBUG_RETURN;
+
+  static void verify_klass(MacroAssembler* _masm,
+                           Register obj, KlassHandle klass,
+                           const char* error_message = "wrong klass") NOT_DEBUG_RETURN;
+
+  static void verify_method_handle(MacroAssembler* _masm, Register mh_reg) {
+    verify_klass(_masm, mh_reg, SystemDictionaryHandles::MethodHandle_klass(),
+                 "reference is a MH");
+  }
+
+  static void trace_method_handle(MacroAssembler* _masm, const char* adaptername) PRODUCT_RETURN;
+
+  static Register saved_last_sp_register() {
+    // Should be in sharedRuntime, not here.
+    return LP64_ONLY(r13) NOT_LP64(rsi);
+  }