1 /*
   2  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2016, 2018, SAP SE. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #ifndef CPU_S390_VM_MACROASSEMBLER_S390_HPP
  27 #define CPU_S390_VM_MACROASSEMBLER_S390_HPP
  28 
  29 #include "asm/assembler.hpp"
  30 #include "oops/accessDecorators.hpp"
  31 
  32 #define MODERN_IFUN(name)  ((void (MacroAssembler::*)(Register, int64_t, Register, Register))&MacroAssembler::name)
  33 #define CLASSIC_IFUN(name) ((void (MacroAssembler::*)(Register, int64_t, Register, Register))&MacroAssembler::name)
  34 #define MODERN_FFUN(name)  ((void (MacroAssembler::*)(FloatRegister, int64_t, Register, Register))&MacroAssembler::name)
  35 #define CLASSIC_FFUN(name) ((void (MacroAssembler::*)(FloatRegister, int64_t, Register, Register))&MacroAssembler::name)
  36 
  37 class MacroAssembler: public Assembler {
  38  public:
  39   MacroAssembler(CodeBuffer* code) : Assembler(code) {}
  40 
  41   //
  42   // Optimized instruction emitters
  43   //
  44 
  45   // Move register if destination register and target register are different.
  46   void lr_if_needed(Register rd, Register rs);
  47   void lgr_if_needed(Register rd, Register rs);
  48   void llgfr_if_needed(Register rd, Register rs);
  49   void ldr_if_needed(FloatRegister rd, FloatRegister rs);
  50 
  51   void move_reg_if_needed(Register dest, BasicType dest_type, Register src, BasicType src_type);
  52   void move_freg_if_needed(FloatRegister dest, BasicType dest_type, FloatRegister src, BasicType src_type);
  53 
  54   void freg2mem_opt(FloatRegister reg,
  55                     int64_t       disp,
  56                     Register      index,
  57                     Register      base,
  58                     void (MacroAssembler::*modern) (FloatRegister, int64_t, Register, Register),
  59                     void (MacroAssembler::*classic)(FloatRegister, int64_t, Register, Register),
  60                     Register      scratch = Z_R0);
  61   void freg2mem_opt(FloatRegister reg,
  62                     const Address &a, bool is_double = true);
  63 
  64   void mem2freg_opt(FloatRegister reg,
  65                     int64_t       disp,
  66                     Register      index,
  67                     Register      base,
  68                     void (MacroAssembler::*modern) (FloatRegister, int64_t, Register, Register),
  69                     void (MacroAssembler::*classic)(FloatRegister, int64_t, Register, Register),
  70                     Register      scratch = Z_R0);
  71   void mem2freg_opt(FloatRegister reg,
  72                     const Address &a, bool is_double = true);
  73 
  74   void reg2mem_opt(Register reg,
  75                    int64_t  disp,
  76                    Register index,
  77                    Register base,
  78                    void (MacroAssembler::*modern) (Register, int64_t, Register, Register),
  79                    void (MacroAssembler::*classic)(Register, int64_t, Register, Register),
  80                    Register scratch = Z_R0);
  81   // returns offset of the store instruction
  82   int reg2mem_opt(Register reg, const Address &a, bool is_double = true);
  83 
  84   void mem2reg_opt(Register reg,
  85                    int64_t  disp,
  86                    Register index,
  87                    Register base,
  88                    void (MacroAssembler::*modern) (Register, int64_t, Register, Register),
  89                    void (MacroAssembler::*classic)(Register, int64_t, Register, Register));
  90   void mem2reg_opt(Register reg, const Address &a, bool is_double = true);
  91   void mem2reg_signed_opt(Register reg, const Address &a);
  92 
  93   // AND immediate and set condition code, works for 64 bit immediates/operation as well.
  94    void and_imm(Register r, long mask, Register tmp = Z_R0, bool wide = false);
  95 
  96   // 1's complement, 32bit or 64bit. Optimized to exploit distinct operands facility.
  97   // Note: The condition code is neither preserved nor correctly set by this code!!!
  98   // Note: (wide == false) does not protect the high order half of the target register
  99   // from alternation. It only serves as optimization hint for 32-bit results.
 100   void not_(Register r1, Register r2 = noreg, bool wide = false);  // r1 = ~r2
 101 
 102   // Expanded support of all "rotate_then_<logicalOP>" instructions.
 103   //
 104   // Generalize and centralize rotate_then_<logicalOP> emitter.
 105   // Functional description. For details, see Principles of Operation, Chapter 7, "Rotate Then Insert..."
 106   //  - Bits  in a register are numbered left (most significant) to right (least significant), i.e. [0..63].
 107   //  - Bytes in a register are numbered left (most significant) to right (least significant), i.e. [0..7].
 108   //  - Register src is rotated to the left by (nRotate&0x3f) positions.
 109   //  - Negative values for nRotate result in a rotation to the right by abs(nRotate) positions.
 110   //  - The bits in positions [lBitPos..rBitPos] of the _ROTATED_ src operand take part in the
 111   //    logical operation performed on the contents (in those positions) of the dst operand.
 112   //  - The logical operation that is performed on the dst operand is one of
 113   //     o insert the selected bits (replacing the original contents of those bit positions)
 114   //     o and the selected bits with the corresponding bits of the dst operand
 115   //     o or  the selected bits with the corresponding bits of the dst operand
 116   //     o xor the selected bits with the corresponding bits of the dst operand
 117   //  - For clear_dst == true, the destination register is cleared before the bits are inserted.
 118   //    For clear_dst == false, only the bit positions that get data inserted from src
 119   //    are changed. All other bit positions remain unchanged.
 120   //  - For test_only == true,  the result of the logicalOP is only used to set the condition code, dst remains unchanged.
 121   //    For test_only == false, the result of the logicalOP replaces the selected bits of dst.
 122   //  - src32bit and dst32bit indicate the respective register is used as 32bit value only.
 123   //    Knowledge can simplify code generation.
 124   //
 125   // Here is an important performance note, valid for all <logicalOP>s except "insert":
 126   //   Due to the too complex nature of the operation, it cannot be done in a single cycle.
 127   //   Timing constraints require the instructions to be cracked into two micro-ops, taking
 128   //   one or two cycles each to execute. In some cases, an additional pipeline bubble might get added.
 129   //   Macroscopically, that makes up for a three- or four-cycle instruction where you would
 130   //   expect just a single cycle.
 131   //   It is thus not beneficial from a performance point of view to exploit those instructions.
 132   //   Other reasons (code compactness, register pressure, ...) might outweigh this penalty.
 133   //
 134   unsigned long create_mask(int lBitPos, int rBitPos);
 135   void rotate_then_mask(Register dst, Register src, int lBitPos, int rBitPos,
 136                         int nRotate, bool src32bit, bool dst32bit, bool oneBits);
 137   void rotate_then_insert(Register dst, Register src, int lBitPos, int rBitPos, int nRotate,
 138                           bool clear_dst);
 139   void rotate_then_and(Register dst, Register src, int lBitPos, int rBitPos, int nRotate,
 140                        bool test_only);
 141   void rotate_then_or(Register dst, Register src, int lBitPos, int rBitPos, int nRotate,
 142                       bool test_onlyt);
 143   void rotate_then_xor(Register dst, Register src, int lBitPos, int rBitPos, int nRotate,
 144                        bool test_only);
 145 
 146   void add64(Register r1, RegisterOrConstant inc);
 147 
 148   // Helper function to multiply the 64bit contents of a register by a 16bit constant.
 149   // The optimization tries to avoid the mghi instruction, since it uses the FPU for
 150   // calculation and is thus rather slow.
 151   //
 152   // There is no handling for special cases, e.g. cval==0 or cval==1.
 153   //
 154   // Returns len of generated code block.
 155   unsigned int mul_reg64_const16(Register rval, Register work, int cval);
 156 
 157   // Generic operation r1 := r2 + imm.
 158   void add2reg(Register r1, int64_t imm, Register r2 = noreg);
 159   // Generic operation r := b + x + d.
 160   void add2reg_with_index(Register r, int64_t d, Register x, Register b = noreg);
 161 
 162   // Add2mem* methods for direct memory increment.
 163   void add2mem_32(const Address &a, int64_t imm, Register tmp);
 164   void add2mem_64(const Address &a, int64_t imm, Register tmp);
 165 
 166   // *((int8_t*)(dst)) |= imm8
 167   inline void or2mem_8(Address& dst, int64_t imm8);
 168 
 169   // Load values by size and signedness.
 170   void load_sized_value(Register dst, Address src, size_t size_in_bytes, bool is_signed);
 171   void store_sized_value(Register src, Address dst, size_t size_in_bytes);
 172 
 173   // Load values with large offsets to base address.
 174  private:
 175   int  split_largeoffset(int64_t si20_offset, Register tmp, bool fixed_codelen, bool accumulate);
 176  public:
 177   void load_long_largeoffset(Register t, int64_t si20, Register a, Register tmp);
 178   void load_float_largeoffset(FloatRegister t, int64_t si20, Register a, Register tmp);
 179   void load_double_largeoffset(FloatRegister t, int64_t si20, Register a, Register tmp);
 180 
 181  private:
 182   long toc_distance();
 183  public:
 184   void load_toc(Register Rtoc);
 185   void load_long_pcrelative(Register Rdst, address dataLocation);
 186   static int load_long_pcrelative_size() { return 6; }
 187   void load_addr_pcrelative(Register Rdst, address dataLocation);
 188   static int load_addr_pcrel_size() { return 6; } // Just a LARL.
 189 
 190   // Load a value from memory and test (set CC).
 191   void load_and_test_byte    (Register dst, const Address &a);
 192   void load_and_test_short   (Register dst, const Address &a);
 193   void load_and_test_int     (Register dst, const Address &a);
 194   void load_and_test_int2long(Register dst, const Address &a);
 195   void load_and_test_long    (Register dst, const Address &a);
 196 
 197   // Test a bit in memory. Result is reflected in CC.
 198   void testbit(const Address &a, unsigned int bit);
 199   // Test a bit in a register. Result is reflected in CC.
 200   void testbit(Register r, unsigned int bitPos);
 201 
 202   void prefetch_read(Address a);
 203   void prefetch_update(Address a);
 204 
 205   // Clear a register, i.e. load const zero into reg. Return len (in bytes) of
 206   // generated instruction(s).
 207   //   whole_reg: Clear 64 bits if true, 32 bits otherwise.
 208   //   set_cc: Use instruction that sets the condition code, if true.
 209   int clear_reg(Register r, bool whole_reg = true, bool set_cc = true);
 210 
 211 #ifdef ASSERT
 212   int preset_reg(Register r, unsigned long pattern, int pattern_len);
 213 #endif
 214 
 215   // Clear (store zeros) a small piece of memory.
 216   // CAUTION: Do not use this for atomic memory clearing. Use store_const() instead.
 217   //   addr: Address descriptor of memory to clear.
 218   //         Index register will not be used!
 219   //   size: Number of bytes to clear.
 220   void clear_mem(const Address& addr, unsigned size);
 221 
 222   // Move immediate values to memory. Currently supports 32 and 64 bit stores,
 223   // but may be extended to 16 bit store operation, if needed.
 224   // For details, see implementation in *.cpp file.
 225          int store_const(const Address &dest, long imm,
 226                          unsigned int lm, unsigned int lc,
 227                          Register scratch = Z_R0);
 228   inline int store_const(const Address &dest, long imm,
 229                          Register scratch = Z_R0, bool is_long = true);
 230 
 231   // Move/initialize arbitrarily large memory area. No check for destructive overlap.
 232   // Being interruptible, these instructions need a retry-loop.
 233   void move_long_ext(Register dst, Register src, unsigned int pad);
 234 
 235   void compare_long_ext(Register left, Register right, unsigned int pad);
 236   void compare_long_uni(Register left, Register right, unsigned int pad);
 237 
 238   void search_string(Register end, Register start);
 239   void search_string_uni(Register end, Register start);
 240 
 241   // Translate instructions
 242   // Being interruptible, these instructions need a retry-loop.
 243   void translate_oo(Register dst, Register src, uint mask);
 244   void translate_ot(Register dst, Register src, uint mask);
 245   void translate_to(Register dst, Register src, uint mask);
 246   void translate_tt(Register dst, Register src, uint mask);
 247 
 248   // Crypto instructions.
 249   // Being interruptible, these instructions need a retry-loop.
 250   void cksm(Register crcBuff, Register srcBuff);
 251   void km( Register dstBuff, Register srcBuff);
 252   void kmc(Register dstBuff, Register srcBuff);
 253   void kimd(Register srcBuff);
 254   void klmd(Register srcBuff);
 255   void kmac(Register srcBuff);
 256 
 257   // nop padding
 258   void align(int modulus);
 259   void align_address(int modulus);
 260 
 261   //
 262   // Constants, loading constants, TOC support
 263   //
 264 
 265   // Load generic address: d <- base(a) + index(a) + disp(a).
 266   inline void load_address(Register d, const Address &a);
 267   // Load absolute address (and try to optimize).
 268   void load_absolute_address(Register d, address addr);
 269 
 270   // Address of Z_ARG1 and argument_offset.
 271   // If temp_reg == arg_slot, arg_slot will be overwritten.
 272   Address argument_address(RegisterOrConstant arg_slot,
 273                            Register temp_reg = noreg,
 274                            int64_t extra_slot_offset = 0);
 275 
 276   // Load a narrow ptr constant (oop or klass ptr).
 277   void load_narrow_oop( Register t, narrowOop a);
 278   void load_narrow_klass(Register t, Klass* k);
 279 
 280   static bool is_load_const_32to64(address pos);
 281   static bool is_load_narrow_oop(address pos)   { return is_load_const_32to64(pos); }
 282   static bool is_load_narrow_klass(address pos) { return is_load_const_32to64(pos); }
 283 
 284   static int  load_const_32to64_size()          { return 6; }
 285   static bool load_narrow_oop_size()            { return load_const_32to64_size(); }
 286   static bool load_narrow_klass_size()          { return load_const_32to64_size(); }
 287 
 288   static int  patch_load_const_32to64(address pos, int64_t a);
 289   static int  patch_load_narrow_oop(address pos, oop o);
 290   static int  patch_load_narrow_klass(address pos, Klass* k);
 291 
 292   // cOops. CLFI exploit.
 293   void compare_immediate_narrow_oop(Register oop1, narrowOop oop2);
 294   void compare_immediate_narrow_klass(Register op1, Klass* op2);
 295   static bool is_compare_immediate32(address pos);
 296   static bool is_compare_immediate_narrow_oop(address pos);
 297   static bool is_compare_immediate_narrow_klass(address pos);
 298   static int  compare_immediate_narrow_size()       { return 6; }
 299   static int  compare_immediate_narrow_oop_size()   { return compare_immediate_narrow_size(); }
 300   static int  compare_immediate_narrow_klass_size() { return compare_immediate_narrow_size(); }
 301   static int  patch_compare_immediate_32(address pos, int64_t a);
 302   static int  patch_compare_immediate_narrow_oop(address pos, oop o);
 303   static int  patch_compare_immediate_narrow_klass(address pos, Klass* k);
 304 
 305   // Load a 32bit constant into a 64bit register.
 306   void load_const_32to64(Register t, int64_t x, bool sign_extend=true);
 307   // Load a 64 bit constant.
 308          void load_const(Register t, long a);
 309   inline void load_const(Register t, void* a);
 310   inline void load_const(Register t, Label& L);
 311   inline void load_const(Register t, const AddressLiteral& a);
 312   // Get the 64 bit constant from a `load_const' sequence.
 313   static long get_const(address load_const);
 314   // Patch the 64 bit constant of a `load_const' sequence. This is a low level
 315   // procedure. It neither flushes the instruction cache nor is it atomic.
 316   static void patch_const(address load_const, long x);
 317   static int load_const_size() { return 12; }
 318 
 319   // Turn a char into boolean. NOTE: destroys r.
 320   void c2bool(Register r, Register t = Z_R0);
 321 
 322   // Optimized version of load_const for constants that do not need to be
 323   // loaded by a sequence of instructions of fixed length and that do not
 324   // need to be patched.
 325   int load_const_optimized_rtn_len(Register t, long x, bool emit);
 326   inline void load_const_optimized(Register t, long x);
 327   inline void load_const_optimized(Register t, void* a);
 328   inline void load_const_optimized(Register t, Label& L);
 329   inline void load_const_optimized(Register t, const AddressLiteral& a);
 330 
 331  public:
 332 
 333   //----------------------------------------------------------
 334   //            oops in code             -------------
 335   //  including compressed oops support  -------------
 336   //----------------------------------------------------------
 337 
 338   // Metadata in code that we have to keep track of.
 339   AddressLiteral allocate_metadata_address(Metadata* obj); // allocate_index
 340   AddressLiteral constant_metadata_address(Metadata* obj); // find_index
 341 
 342   // allocate_index
 343   AddressLiteral allocate_oop_address(jobject obj);
 344   // find_index
 345   AddressLiteral constant_oop_address(jobject obj);
 346   // Uses allocate_oop_address.
 347   inline void set_oop         (jobject obj, Register d);
 348   // Uses constant_oop_address.
 349   inline void set_oop_constant(jobject obj, Register d);
 350   // Uses constant_metadata_address.
 351   inline bool set_metadata_constant(Metadata* md, Register d);
 352 
 353   virtual RegisterOrConstant delayed_value_impl(intptr_t* delayed_value_addr,
 354                                                 Register tmp,
 355                                                 int offset);
 356   //
 357   // branch, jump
 358   //
 359 
 360   // Use one generic function for all branch patches.
 361   static unsigned long patched_branch(address dest_pos, unsigned long inst, address inst_pos);
 362 
 363   void pd_patch_instruction(address branch, address target, const char* file, int line);
 364 
 365   // Extract relative address from "relative" instructions.
 366   static long get_pcrel_offset(unsigned long inst);
 367   static long get_pcrel_offset(address pc);
 368   static address get_target_addr_pcrel(address pc);
 369 
 370   static inline bool is_call_pcrelative_short(unsigned long inst);
 371   static inline bool is_call_pcrelative_long(unsigned long inst);
 372   static inline bool is_branch_pcrelative_short(unsigned long inst);
 373   static inline bool is_branch_pcrelative_long(unsigned long inst);
 374   static inline bool is_compareandbranch_pcrelative_short(unsigned long inst);
 375   static inline bool is_branchoncount_pcrelative_short(unsigned long inst);
 376   static inline bool is_branchonindex32_pcrelative_short(unsigned long inst);
 377   static inline bool is_branchonindex64_pcrelative_short(unsigned long inst);
 378   static inline bool is_branchonindex_pcrelative_short(unsigned long inst);
 379   static inline bool is_branch_pcrelative16(unsigned long inst);
 380   static inline bool is_branch_pcrelative32(unsigned long inst);
 381   static inline bool is_branch_pcrelative(unsigned long inst);
 382   static inline bool is_load_pcrelative_long(unsigned long inst);
 383   static inline bool is_misc_pcrelative_long(unsigned long inst);
 384   static inline bool is_pcrelative_short(unsigned long inst);
 385   static inline bool is_pcrelative_long(unsigned long inst);
 386   // PCrelative TOC access. Variants with address argument.
 387   static inline bool is_load_pcrelative_long(address iLoc);
 388   static inline bool is_pcrelative_short(address iLoc);
 389   static inline bool is_pcrelative_long(address iLoc);
 390 
 391   static inline bool is_pcrelative_instruction(address iloc);
 392   static inline bool is_load_addr_pcrel(address a);
 393 
 394   static void patch_target_addr_pcrel(address pc, address con);
 395   static void patch_addr_pcrel(address pc, address con) {
 396     patch_target_addr_pcrel(pc, con); // Just delegate. This is only for nativeInst_s390.cpp.
 397   }
 398 
 399   //---------------------------------------------------------
 400   //  Some macros for more comfortable assembler programming.
 401   //---------------------------------------------------------
 402 
 403   // NOTE: pass NearLabel T to signal that the branch target T will be bound to a near address.
 404 
 405   void compare32_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& target);
 406   void compareU32_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& target);
 407   void compare64_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& target);
 408   void compareU64_and_branch(Register r1, RegisterOrConstant x2, branch_condition cond, Label& target);
 409 
 410   void branch_optimized(Assembler::branch_condition cond, address branch_target);
 411   void branch_optimized(Assembler::branch_condition cond, Label&  branch_target);
 412   void compare_and_branch_optimized(Register r1,
 413                                     Register r2,
 414                                     Assembler::branch_condition cond,
 415                                     address  branch_addr,
 416                                     bool     len64,
 417                                     bool     has_sign);
 418   void compare_and_branch_optimized(Register r1,
 419                                     jlong    x2,
 420                                     Assembler::branch_condition cond,
 421                                     Label&   branch_target,
 422                                     bool     len64,
 423                                     bool     has_sign);
 424   void compare_and_branch_optimized(Register r1,
 425                                     Register r2,
 426                                     Assembler::branch_condition cond,
 427                                     Label&   branch_target,
 428                                     bool     len64,
 429                                     bool     has_sign);
 430 
 431   //
 432   // Support for frame handling
 433   //
 434   // Specify the register that should be stored as the return pc in the
 435   // current frame (default is R14).
 436   inline void save_return_pc(Register pc = Z_R14);
 437   inline void restore_return_pc();
 438 
 439   // Get current PC.
 440   address get_PC(Register result);
 441 
 442   // Get current PC + offset. Offset given in bytes, must be even!
 443   address get_PC(Register result, int64_t offset);
 444 
 445   // Get size of instruction at pc (which must point to valid code).
 446   void instr_size(Register size, Register pc);
 447 
 448   // Accessing, and in particular modifying, a stack location is only safe if
 449   // the stack pointer (Z_SP) is set such that the accessed stack location is
 450   // in the reserved range.
 451   //
 452   // From a performance point of view, it is desirable not to change the SP
 453   // first and then immediately use it to access the freshly reserved space.
 454   // That opens a small gap, though. If, just after storing some value (the
 455   // frame pointer) into the to-be-reserved space, an interrupt is caught,
 456   // the handler might use the space beyond Z_SP for it's own purpose.
 457   // If that happens, the stored value might get altered.
 458 
 459   // Resize current frame either relatively wrt to current SP or absolute.
 460   void resize_frame_sub(Register offset, Register fp, bool load_fp=true);
 461   void resize_frame_abs_with_offset(Register newSP, Register fp, int offset, bool load_fp);
 462   void resize_frame_absolute(Register addr, Register fp, bool load_fp);
 463   void resize_frame(RegisterOrConstant offset, Register fp, bool load_fp=true);
 464 
 465   // Push a frame of size bytes, if copy_sp is false, old_sp must already
 466   // contain a copy of Z_SP.
 467   void push_frame(Register bytes, Register old_sp, bool copy_sp = true, bool bytes_with_inverted_sign = false);
 468 
 469   // Push a frame of size `bytes'. no abi space provided.
 470   // Don't rely on register locking, instead pass a scratch register
 471   // (Z_R0 by default).
 472   // CAUTION! passing registers >= Z_R2 may produce bad results on
 473   // old CPUs!
 474   unsigned int push_frame(unsigned int bytes, Register scratch = Z_R0);
 475 
 476   // Push a frame of size `bytes' with abi160 on top.
 477   unsigned int push_frame_abi160(unsigned int bytes);
 478 
 479   // Pop current C frame.
 480   void pop_frame();
 481   // Pop current C frame and restore return PC register (Z_R14).
 482   void pop_frame_restore_retPC(int frame_size_in_bytes);
 483 
 484   //
 485   // Calls
 486   //
 487 
 488  private:
 489   address _last_calls_return_pc;
 490 
 491  public:
 492   // Support for VM calls. This is the base routine called by the
 493   // different versions of call_VM_leaf. The interpreter may customize
 494   // this version by overriding it for its purposes (e.g., to
 495   // save/restore additional registers when doing a VM call).
 496   void call_VM_leaf_base(address entry_point);
 497   void call_VM_leaf_base(address entry_point, bool allow_relocation);
 498 
 499   // It is imperative that all calls into the VM are handled via the
 500   // call_VM macros. They make sure that the stack linkage is setup
 501   // correctly. Call_VM's correspond to ENTRY/ENTRY_X entry points
 502   // while call_VM_leaf's correspond to LEAF entry points.
 503   //
 504   // This is the base routine called by the different versions of
 505   // call_VM. The interpreter may customize this version by overriding
 506   // it for its purposes (e.g., to save/restore additional registers
 507   // when doing a VM call).
 508 
 509   // If no last_java_sp is specified (noreg) then SP will be used instead.
 510 
 511   virtual void call_VM_base(
 512     Register        oop_result,        // Where an oop-result ends up if any; use noreg otherwise.
 513     Register        last_java_sp,      // To set up last_Java_frame in stubs; use noreg otherwise.
 514     address         entry_point,       // The entry point.
 515     bool            check_exception);  // Flag which indicates if exception should be checked.
 516   virtual void call_VM_base(
 517     Register        oop_result,       // Where an oop-result ends up if any; use noreg otherwise.
 518     Register        last_java_sp,     // To set up last_Java_frame in stubs; use noreg otherwise.
 519     address         entry_point,      // The entry point.
 520     bool            allow_relocation, // Flag to request generation of relocatable code.
 521     bool            check_exception); // Flag which indicates if exception should be checked.
 522 
 523   // Call into the VM.
 524   // Passes the thread pointer (in Z_ARG1) as a prepended argument.
 525   // Makes sure oop return values are visible to the GC.
 526   void call_VM(Register oop_result, address entry_point, bool check_exceptions = true);
 527   void call_VM(Register oop_result, address entry_point, Register arg_1, bool check_exceptions = true);
 528   void call_VM(Register oop_result, address entry_point, Register arg_1, Register arg_2, bool check_exceptions = true);
 529   void call_VM(Register oop_result, address entry_point, Register arg_1, Register arg_2,
 530                Register arg_3, bool check_exceptions = true);
 531 
 532   void call_VM_static(Register oop_result, address entry_point, bool check_exceptions = true);
 533   void call_VM_static(Register oop_result, address entry_point, Register arg_1, Register arg_2,
 534                       Register arg_3, bool check_exceptions = true);
 535 
 536   // Overloaded with last_java_sp.
 537   void call_VM(Register oop_result, Register last_java_sp, address entry_point, bool check_exceptions = true);
 538   void call_VM(Register oop_result, Register last_java_sp, address entry_point,
 539                Register arg_1, bool check_exceptions = true);
 540   void call_VM(Register oop_result, Register last_java_sp, address entry_point,
 541                Register arg_1, Register arg_2, bool check_exceptions = true);
 542   void call_VM(Register oop_result, Register last_java_sp, address entry_point,
 543                Register arg_1, Register arg_2, Register arg_3, bool check_exceptions = true);
 544 
 545   void call_VM_leaf(address entry_point);
 546   void call_VM_leaf(address entry_point, Register arg_1);
 547   void call_VM_leaf(address entry_point, Register arg_1, Register arg_2);
 548   void call_VM_leaf(address entry_point, Register arg_1, Register arg_2, Register arg_3);
 549 
 550   // Really static VM leaf call (never patched).
 551   void call_VM_leaf_static(address entry_point);
 552   void call_VM_leaf_static(address entry_point, Register arg_1);
 553   void call_VM_leaf_static(address entry_point, Register arg_1, Register arg_2);
 554   void call_VM_leaf_static(address entry_point, Register arg_1, Register arg_2, Register arg_3);
 555 
 556   // Call a C function via its function entry. Updates and returns _last_calls_return_pc.
 557   inline address call(Register function_entry);
 558   inline address call_c(Register function_entry);
 559          address call_c(address function_entry);
 560   // Variant for really static (non-relocatable) calls which are never patched.
 561          address call_c_static(address function_entry);
 562   // TOC or pc-relative call + emits a runtime_call relocation.
 563          address call_c_opt(address function_entry);
 564 
 565   inline address call_stub(Register function_entry);
 566   inline address call_stub(address  function_entry);
 567 
 568   // Get the pc where the last call will return to. Returns _last_calls_return_pc.
 569   inline address last_calls_return_pc();
 570 
 571  private:
 572   static bool is_call_far_patchable_variant0_at(address instruction_addr); // Dynamic TOC: load target addr from CP and call.
 573   static bool is_call_far_patchable_variant2_at(address instruction_addr); // PC-relative call, prefixed with NOPs.
 574 
 575 
 576  public:
 577   bool           call_far_patchable(address target, int64_t toc_offset);
 578   static bool    is_call_far_patchable_at(address inst_start);             // All supported forms of patchable calls.
 579   static bool    is_call_far_patchable_pcrelative_at(address inst_start);  // Pc-relative call with leading nops.
 580   static bool    is_call_far_pcrelative(address instruction_addr);         // Pure far pc-relative call, with one leading size adjustment nop.
 581   static void    set_dest_of_call_far_patchable_at(address inst_start, address target, int64_t toc_offset);
 582   static address get_dest_of_call_far_patchable_at(address inst_start, address toc_start);
 583 
 584   void align_call_far_patchable(address pc);
 585 
 586   // PCrelative TOC access.
 587 
 588   // This value is independent of code position - constant for the lifetime of the VM.
 589   static int call_far_patchable_size() {
 590     return load_const_from_toc_size() + call_byregister_size();
 591   }
 592 
 593   static int call_far_patchable_ret_addr_offset() { return call_far_patchable_size(); }
 594 
 595   static bool call_far_patchable_requires_alignment_nop(address pc) {
 596     int size = call_far_patchable_size();
 597     return ((intptr_t)(pc + size) & 0x03L) != 0;
 598   }
 599 
 600   // END OF PCrelative TOC access.
 601 
 602   static int jump_byregister_size()          { return 2; }
 603   static int jump_pcrelative_size()          { return 4; }
 604   static int jump_far_pcrelative_size()      { return 6; }
 605   static int call_byregister_size()          { return 2; }
 606   static int call_pcrelative_size()          { return 4; }
 607   static int call_far_pcrelative_size()      { return 2 + 6; } // Prepend each BRASL with a nop.
 608   static int call_far_pcrelative_size_raw()  { return 6; }     // Prepend each BRASL with a nop.
 609 
 610   //
 611   // Java utilities
 612   //
 613 
 614   // These routines should emit JVMTI PopFrame and ForceEarlyReturn handling code.
 615   // The implementation is only non-empty for the InterpreterMacroAssembler,
 616   // as only the interpreter handles PopFrame and ForceEarlyReturn requests.
 617   virtual void check_and_handle_popframe(Register java_thread);
 618   virtual void check_and_handle_earlyret(Register java_thread);
 619 
 620   // Polling page support.
 621   enum poll_mask {
 622     mask_stackbang = 0xde, // 222 (dec)
 623     mask_safepoint = 0x6f, // 111 (dec)
 624     mask_profiling = 0xba  // 186 (dec)
 625   };
 626 
 627   // Read from the polling page.
 628   void load_from_polling_page(Register polling_page_address, int64_t offset = 0);
 629 
 630   // Check if given instruction is a read from the polling page
 631   // as emitted by load_from_polling_page.
 632   static bool is_load_from_polling_page(address instr_loc);
 633   // Extract poll address from instruction and ucontext.
 634   static address get_poll_address(address instr_loc, void* ucontext);
 635   // Extract poll register from instruction.
 636   static uint get_poll_register(address instr_loc);
 637 
 638   // Check if instruction is a write access to the memory serialization page
 639   // realized by one of the instructions stw, stwu, stwx, or stwux.
 640   static bool is_memory_serialization(int instruction, JavaThread* thread, void* ucontext);
 641 
 642   // Support for serializing memory accesses between threads.
 643   void serialize_memory(Register thread, Register tmp1, Register tmp2);
 644 
 645   // Check if safepoint requested and if so branch
 646   void safepoint_poll(Label& slow_path, Register temp_reg);
 647 
 648   // Stack overflow checking
 649   void bang_stack_with_offset(int offset);
 650 
 651   // Check for reserved stack access in method being exited. If the reserved
 652   // stack area was accessed, protect it again and throw StackOverflowError.
 653   // Uses Z_R1.
 654   void reserved_stack_check(Register return_pc);
 655 
 656   // Atomics
 657   // -- none?
 658 
 659   void tlab_allocate(Register obj,                // Result: pointer to object after successful allocation
 660                      Register var_size_in_bytes,  // Object size in bytes if unknown at compile time; invalid otherwise.
 661                      int      con_size_in_bytes,  // Object size in bytes if   known at compile time.
 662                      Register t1,                 // temp register
 663                      Label&   slow_case);         // Continuation point if fast allocation fails.
 664 
 665   // Emitter for interface method lookup.
 666   //   input: recv_klass, intf_klass, itable_index
 667   //   output: method_result
 668   //   kills: itable_index, temp1_reg, Z_R0, Z_R1
 669   void lookup_interface_method(Register           recv_klass,
 670                                Register           intf_klass,
 671                                RegisterOrConstant itable_index,
 672                                Register           method_result,
 673                                Register           temp1_reg,
 674                                Label&             no_such_interface,
 675                                bool               return_method = true);
 676 
 677   // virtual method calling
 678   void lookup_virtual_method(Register             recv_klass,
 679                              RegisterOrConstant   vtable_index,
 680                              Register             method_result);
 681 
 682   // Factor out code to call ic_miss_handler.
 683   unsigned int call_ic_miss_handler(Label& ICM, int trapMarker, int requiredSize, Register scratch);
 684   void nmethod_UEP(Label& ic_miss);
 685 
 686   // Emitters for "partial subtype" checks.
 687 
 688   // Test sub_klass against super_klass, with fast and slow paths.
 689 
 690   // The fast path produces a tri-state answer: yes / no / maybe-slow.
 691   // One of the three labels can be NULL, meaning take the fall-through.
 692   // If super_check_offset is -1, the value is loaded up from super_klass.
 693   // No registers are killed, except temp_reg and temp2_reg.
 694   // If super_check_offset is not -1, temp1_reg is not used and can be noreg.
 695   void check_klass_subtype_fast_path(Register sub_klass,
 696                                      Register super_klass,
 697                                      Register temp1_reg,
 698                                      Label*   L_success,
 699                                      Label*   L_failure,
 700                                      Label*   L_slow_path,
 701                                      RegisterOrConstant super_check_offset = RegisterOrConstant(-1));
 702 
 703   // The rest of the type check; must be wired to a corresponding fast path.
 704   // It does not repeat the fast path logic, so don't use it standalone.
 705   // The temp_reg can be noreg, if no temps are available.
 706   // It can also be sub_klass or super_klass, meaning it's OK to kill that one.
 707   // Updates the sub's secondary super cache as necessary.
 708   void check_klass_subtype_slow_path(Register Rsubklass,
 709                                      Register Rsuperklas,
 710                                      Register Rarray_ptr, // tmp
 711                                      Register Rlength,    // tmp
 712                                      Label* L_success,
 713                                      Label* L_failure);
 714 
 715   // Simplified, combined version, good for typical uses.
 716   // Falls through on failure.
 717   void check_klass_subtype(Register sub_klass,
 718                            Register super_klass,
 719                            Register temp1_reg,
 720                            Register temp2_reg,
 721                            Label&   L_success);
 722 
 723   // Increment a counter at counter_address when the eq condition code is set.
 724   // Kills registers tmp1_reg and tmp2_reg and preserves the condition code.
 725   void increment_counter_eq(address counter_address, Register tmp1_reg, Register tmp2_reg);
 726   // Biased locking support
 727   // Upon entry,obj_reg must contain the target object, and mark_reg
 728   // must contain the target object's header.
 729   // Destroys mark_reg if an attempt is made to bias an anonymously
 730   // biased lock. In this case a failure will go either to the slow
 731   // case or fall through with the notEqual condition code set with
 732   // the expectation that the slow case in the runtime will be called.
 733   // In the fall-through case where the CAS-based lock is done,
 734   // mark_reg is not destroyed.
 735   void biased_locking_enter(Register obj_reg, Register mark_reg, Register temp_reg,
 736                             Register temp2_reg, Label& done, Label* slow_case = NULL);
 737   // Upon entry, the base register of mark_addr must contain the oop.
 738   // Destroys temp_reg.
 739   // If allow_delay_slot_filling is set to true, the next instruction
 740   // emitted after this one will go in an annulled delay slot if the
 741   // biased locking exit case failed.
 742   void biased_locking_exit(Register mark_addr, Register temp_reg, Label& done);
 743 
 744   void compiler_fast_lock_object(Register oop, Register box, Register temp1, Register temp2, bool try_bias = UseBiasedLocking);
 745   void compiler_fast_unlock_object(Register oop, Register box, Register temp1, Register temp2, bool try_bias = UseBiasedLocking);
 746 
 747   void resolve_jobject(Register value, Register tmp1, Register tmp2);
 748 
 749   // Support for last Java frame (but use call_VM instead where possible).
 750  private:
 751   void set_last_Java_frame(Register last_Java_sp, Register last_Java_pc, bool allow_relocation);
 752   void reset_last_Java_frame(bool allow_relocation);
 753   void set_top_ijava_frame_at_SP_as_last_Java_frame(Register sp, Register tmp1, bool allow_relocation);
 754  public:
 755   inline void set_last_Java_frame(Register last_java_sp, Register last_Java_pc);
 756   inline void set_last_Java_frame_static(Register last_java_sp, Register last_Java_pc);
 757   inline void reset_last_Java_frame(void);
 758   inline void reset_last_Java_frame_static(void);
 759   inline void set_top_ijava_frame_at_SP_as_last_Java_frame(Register sp, Register tmp1);
 760   inline void set_top_ijava_frame_at_SP_as_last_Java_frame_static(Register sp, Register tmp1);
 761 
 762   void set_thread_state(JavaThreadState new_state);
 763 
 764   // Read vm result from thread.
 765   void get_vm_result  (Register oop_result);
 766   void get_vm_result_2(Register result);
 767 
 768   // Vm result is currently getting hijacked to for oop preservation.
 769   void set_vm_result(Register oop_result);
 770 
 771   // Support for NULL-checks
 772   //
 773   // Generates code that causes a NULL OS exception if the content of reg is NULL.
 774   // If the accessed location is M[reg + offset] and the offset is known, provide the
 775   // offset. No explicit code generation is needed if the offset is within a certain
 776   // range (0 <= offset <= page_size).
 777   //
 778   // %%%%%% Currently not done for z/Architecture
 779 
 780   void null_check(Register reg, Register tmp = Z_R0, int64_t offset = -1);
 781   static bool needs_explicit_null_check(intptr_t offset);  // Implemented in shared file ?!
 782 
 783   // Klass oop manipulations if compressed.
 784   void encode_klass_not_null(Register dst, Register src = noreg);
 785   void decode_klass_not_null(Register dst, Register src);
 786   void decode_klass_not_null(Register dst);
 787   void load_klass(Register klass, Address mem);
 788   void load_klass(Register klass, Register src_oop);
 789   void load_prototype_header(Register Rheader, Register Rsrc_oop);
 790   void store_klass(Register klass, Register dst_oop, Register ck = noreg); // Klass will get compressed if ck not provided.
 791   void store_klass_gap(Register s, Register dst_oop);
 792 
 793   // This function calculates the size of the code generated by
 794   //   decode_klass_not_null(register dst)
 795   // when (Universe::heap() != NULL). Hence, if the instructions
 796   // it generates change, then this method needs to be updated.
 797   static int instr_size_for_decode_klass_not_null();
 798 
 799   void encode_heap_oop(Register oop);
 800   void encode_heap_oop_not_null(Register oop);
 801 
 802   static int get_oop_base_pow2_offset(uint64_t oop_base);
 803   int  get_oop_base(Register Rbase, uint64_t oop_base);
 804   int  get_oop_base_complement(Register Rbase, uint64_t oop_base);
 805   void compare_heap_oop(Register Rop1, Address mem, bool maybeNULL);
 806   void compare_klass_ptr(Register Rop1, int64_t disp, Register Rbase, bool maybeNULL);
 807 
 808   // Access heap oop, handle encoding and GC barriers.
 809  private:
 810   void access_store_at(BasicType type, DecoratorSet decorators,
 811                        const Address& addr, Register val,
 812                        Register tmp1, Register tmp2, Register tmp3);
 813   void access_load_at(BasicType type, DecoratorSet decorators,
 814                       const Address& addr, Register dst,
 815                       Register tmp1, Register tmp2, Label *is_null = NULL);
 816 
 817  public:
 818   // tmp1 and tmp2 are used with decorators ON_PHANTOM_OOP_REF or ON_WEAK_OOP_REF.
 819   void load_heap_oop(Register dest, const Address &a,
 820                      Register tmp1, Register tmp2,
 821                      DecoratorSet decorators = 0, Label *is_null = NULL);
 822   void store_heap_oop(Register Roop, const Address &a,
 823                       Register tmp1, Register tmp2, Register tmp3,
 824                       DecoratorSet decorators = 0);
 825 
 826   void oop_encoder(Register Rdst, Register Rsrc, bool maybeNULL,
 827                    Register Rbase = Z_R1, int pow2_offset = -1, bool only32bitValid = false);
 828   void oop_decoder(Register Rdst, Register Rsrc, bool maybeNULL,
 829                    Register Rbase = Z_R1, int pow2_offset = -1);
 830 
 831   void resolve_oop_handle(Register result);
 832   void load_mirror(Register mirror, Register method);
 833 
 834   //--------------------------
 835   //---  Operations on arrays.
 836   //--------------------------
 837   unsigned int Clear_Array(Register cnt_arg, Register base_pointer_arg, Register src_addr, Register src_len);
 838   unsigned int Clear_Array_Const(long cnt, Register base);
 839   unsigned int Clear_Array_Const_Big(long cnt, Register base_pointer_arg, Register src_addr, Register src_len);
 840   unsigned int CopyRawMemory_AlignedDisjoint(Register src_reg, Register dst_reg,
 841                                              Register cnt_reg,
 842                                              Register tmp1_reg, Register tmp2_reg);
 843 
 844   //-------------------------------------------
 845   // Special String Intrinsics Implementation.
 846   //-------------------------------------------
 847   // Intrinsics for CompactStrings
 848   //   Restores: src, dst
 849   //   Uses:     cnt
 850   //   Kills:    tmp, Z_R0, Z_R1.
 851   //   Early clobber: result.
 852   //   Boolean precise controls accuracy of result value.
 853   unsigned int string_compress(Register result, Register src, Register dst, Register cnt,
 854                                Register tmp,    bool precise);
 855 
 856   // Inflate byte[] to char[].
 857   unsigned int string_inflate_trot(Register src, Register dst, Register cnt, Register tmp);
 858 
 859   // Inflate byte[] to char[].
 860   //   Restores: src, dst
 861   //   Uses:     cnt
 862   //   Kills:    tmp, Z_R0, Z_R1.
 863   unsigned int string_inflate(Register src, Register dst, Register cnt, Register tmp);
 864 
 865   // Inflate byte[] to char[], length known at compile time.
 866   //   Restores: src, dst
 867   //   Kills:    tmp, Z_R0, Z_R1.
 868   // Note:
 869   //   len is signed int. Counts # characters, not bytes.
 870   unsigned int string_inflate_const(Register src, Register dst, Register tmp, int len);
 871 
 872   // Kills src.
 873   unsigned int has_negatives(Register result, Register src, Register cnt,
 874                              Register odd_reg, Register even_reg, Register tmp);
 875 
 876   unsigned int string_compare(Register str1, Register str2, Register cnt1, Register cnt2,
 877                               Register odd_reg, Register even_reg, Register result, int ae);
 878 
 879   unsigned int array_equals(bool is_array_equ, Register ary1, Register ary2, Register limit,
 880                             Register odd_reg, Register even_reg, Register result, bool is_byte);
 881 
 882   unsigned int string_indexof(Register result, Register haystack, Register haycnt,
 883                               Register needle, Register needlecnt, int needlecntval,
 884                               Register odd_reg, Register even_reg, int ae);
 885 
 886   unsigned int string_indexof_char(Register result, Register haystack, Register haycnt,
 887                                    Register needle, jchar needleChar, Register odd_reg, Register even_reg, bool is_byte);
 888 
 889   // Emit an oop const to the constant pool and set a relocation info
 890   // with address current_pc. Return the TOC offset of the constant.
 891   int store_const_in_toc(AddressLiteral& val);
 892   int store_oop_in_toc(AddressLiteral& oop);
 893   // Emit an oop const to the constant pool via store_oop_in_toc, or
 894   // emit a scalar const to the constant pool via store_const_in_toc,
 895   // and load the constant into register dst.
 896   bool load_const_from_toc(Register dst, AddressLiteral& a, Register Rtoc = noreg);
 897   // Get CPU version dependent size of load_const sequence.
 898   // The returned value is valid only for code sequences
 899   // generated by load_const, not load_const_optimized.
 900   static int load_const_from_toc_size() {
 901     return load_long_pcrelative_size();
 902   }
 903   bool load_oop_from_toc(Register dst, AddressLiteral& a, Register Rtoc = noreg);
 904   static intptr_t get_const_from_toc(address pc);
 905   static void     set_const_in_toc(address pc, unsigned long new_data, CodeBlob *cb);
 906 
 907   // Dynamic TOC.
 908   static bool is_load_const(address a);
 909   static bool is_load_const_from_toc_pcrelative(address a);
 910   static bool is_load_const_from_toc(address a) { return is_load_const_from_toc_pcrelative(a); }
 911 
 912   // PCrelative TOC access.
 913   static bool is_call_byregister(address a) { return is_z_basr(*(short*)a); }
 914   static bool is_load_const_from_toc_call(address a);
 915   static bool is_load_const_call(address a);
 916   static int load_const_call_size() { return load_const_size() + call_byregister_size(); }
 917   static int load_const_from_toc_call_size() { return load_const_from_toc_size() + call_byregister_size(); }
 918   // Offset is +/- 2**32 -> use long.
 919   static long get_load_const_from_toc_offset(address a);
 920 
 921 
 922   void generate_type_profiling(const Register Rdata,
 923                                const Register Rreceiver_klass,
 924                                const Register Rwanted_receiver_klass,
 925                                const Register Rmatching_row,
 926                                bool is_virtual_call);
 927 
 928   // Bit operations for single register operands.
 929   inline void lshift(Register r, int places, bool doubl = true);   // <<
 930   inline void rshift(Register r, int places, bool doubl = true);   // >>
 931 
 932   //
 933   // Debugging
 934   //
 935 
 936   // Assert on CC (condition code in CPU state).
 937   void asm_assert(bool check_equal, const char* msg, int id) PRODUCT_RETURN;
 938   void asm_assert_low(const char *msg, int id) PRODUCT_RETURN;
 939   void asm_assert_high(const char *msg, int id) PRODUCT_RETURN;
 940   void asm_assert_eq(const char* msg, int id) { asm_assert(true, msg, id); }
 941   void asm_assert_ne(const char* msg, int id) { asm_assert(false, msg, id); }
 942 
 943   void asm_assert_static(bool check_equal, const char* msg, int id) PRODUCT_RETURN;
 944 
 945  private:
 946   // Emit assertions.
 947   void asm_assert_mems_zero(bool check_equal, bool allow_relocation, int size, int64_t mem_offset,
 948                             Register mem_base, const char* msg, int id) PRODUCT_RETURN;
 949 
 950  public:
 951   inline void asm_assert_mem4_is_zero(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 952     asm_assert_mems_zero(true,  true, 4, mem_offset, mem_base, msg, id);
 953   }
 954   inline void asm_assert_mem8_is_zero(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 955     asm_assert_mems_zero(true,  true, 8, mem_offset, mem_base, msg, id);
 956   }
 957   inline void asm_assert_mem4_isnot_zero(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 958     asm_assert_mems_zero(false, true, 4, mem_offset, mem_base, msg, id);
 959   }
 960   inline void asm_assert_mem8_isnot_zero(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 961     asm_assert_mems_zero(false, true, 8, mem_offset, mem_base, msg, id);
 962   }
 963 
 964   inline void asm_assert_mem4_is_zero_static(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 965     asm_assert_mems_zero(true,  false, 4, mem_offset, mem_base, msg, id);
 966   }
 967   inline void asm_assert_mem8_is_zero_static(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 968     asm_assert_mems_zero(true,  false, 8, mem_offset, mem_base, msg, id);
 969   }
 970   inline void asm_assert_mem4_isnot_zero_static(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 971     asm_assert_mems_zero(false, false, 4, mem_offset, mem_base, msg, id);
 972   }
 973   inline void asm_assert_mem8_isnot_zero_static(int64_t mem_offset, Register mem_base, const char* msg, int id) {
 974     asm_assert_mems_zero(false, false, 8, mem_offset, mem_base, msg, id);
 975   }
 976   void asm_assert_frame_size(Register expected_size, Register tmp, const char* msg, int id) PRODUCT_RETURN;
 977 
 978   // Verify Z_thread contents.
 979   void verify_thread();
 980 
 981   // Only if +VerifyOops.
 982   void verify_oop(Register reg, const char* s = "broken oop");
 983 
 984   // TODO: verify_method and klass metadata (compare against vptr?).
 985   void _verify_method_ptr(Register reg, const char * msg, const char * file, int line) {}
 986   void _verify_klass_ptr(Register reg, const char * msg, const char * file, int line) {}
 987 
 988 #define verify_method_ptr(reg) _verify_method_ptr(reg, "broken method " #reg, __FILE__, __LINE__)
 989 #define verify_klass_ptr(reg) _verify_klass_ptr(reg, "broken klass " #reg, __FILE__, __LINE__)
 990 
 991  private:
 992   // Generate printout in stop().
 993   static const char* stop_types[];
 994   enum {
 995     stop_stop               = 0,
 996     stop_untested           = 1,
 997     stop_unimplemented      = 2,
 998     stop_shouldnotreachhere = 3,
 999     stop_end                = 4
1000   };
1001   // Prints msg and stops execution.
1002   void    stop(int type, const char* msg, int id = 0);
1003   address stop_chain(address reentry, int type, const char* msg, int id, bool allow_relocation); // Non-relocateable code only!!
1004   void    stop_static(int type, const char* msg, int id);                                        // Non-relocateable code only!!
1005 
1006  public:
1007 
1008   // Prints msg and stops.
1009   address stop_chain(      address reentry, const char* msg = "", int id = 0) { return stop_chain(reentry, stop_stop, msg, id, true); }
1010   address stop_chain_static(address reentry, const char* msg = "", int id = 0) { return stop_chain(reentry, stop_stop, msg, id, false); }
1011   void stop_static  (const char* msg = "", int id = 0) { stop_static(stop_stop,   msg, id); }
1012   void stop         (const char* msg = "", int id = 0) { stop(stop_stop,          msg, id); }
1013   void untested     (const char* msg = "", int id = 0) { stop(stop_untested,      msg, id); }
1014   void unimplemented(const char* msg = "", int id = 0) { stop(stop_unimplemented, msg, id); }
1015   void should_not_reach_here(const char* msg = "", int id = -1) { stop(stop_shouldnotreachhere, msg, id); }
1016 
1017   // Factor out part of stop into subroutine to save space.
1018   void stop_subroutine();
1019 
1020   // Prints msg, but don't stop.
1021   void warn(const char* msg);
1022 
1023   //-----------------------------
1024   //---  basic block tracing code
1025   //-----------------------------
1026   void trace_basic_block(uint i);
1027   void init_basic_block_trace();
1028   // Number of bytes a basic block gets larger due to the tracing code macro (worst case).
1029   // Currently, worst case is 48 bytes. 64 puts us securely on the safe side.
1030   static int basic_blck_trace_blk_size_incr() { return 64; }
1031 
1032   // Write pattern 0x0101010101010101 in region [low-before, high+after].
1033   // Low and high may be the same registers. Before and after are
1034   // the numbers of 8-byte words.
1035   void zap_from_to(Register low, Register high, Register tmp1 = Z_R0, Register tmp2 = Z_R1,
1036                    int before = 0, int after = 0) PRODUCT_RETURN;
1037 
1038   // Emitters for CRC32 calculation.
1039   // A note on invertCRC:
1040   //   Unfortunately, internal representation of crc differs between CRC32 and CRC32C.
1041   //   CRC32 holds it's current crc value in the externally visible representation.
1042   //   CRC32C holds it's current crc value in internal format, ready for updating.
1043   //   Thus, the crc value must be bit-flipped before updating it in the CRC32 case.
1044   //   In the CRC32C case, it must be bit-flipped when it is given to the outside world (getValue()).
1045   //   The bool invertCRC parameter indicates whether bit-flipping is required before updates.
1046  private:
1047   void fold_byte_crc32(Register crc, Register table, Register val, Register tmp);
1048   void fold_8bit_crc32(Register crc, Register table, Register tmp);
1049   void update_byte_crc32( Register crc, Register val, Register table);
1050   void update_byteLoop_crc32(Register crc, Register buf, Register len, Register table,
1051                              Register data);
1052   void update_1word_crc32(Register crc, Register buf, Register table, int bufDisp, int bufInc,
1053                           Register t0,  Register t1,  Register t2,  Register t3);
1054  public:
1055   void kernel_crc32_singleByteReg(Register crc, Register val, Register table,
1056                                   bool invertCRC);
1057   void kernel_crc32_singleByte(Register crc, Register buf, Register len, Register table, Register tmp,
1058                                bool invertCRC);
1059   void kernel_crc32_1byte(Register crc, Register buf, Register len, Register table,
1060                           Register t0,  Register t1,  Register t2,  Register t3,
1061                           bool invertCRC);
1062   void kernel_crc32_1word(Register crc, Register buf, Register len, Register table,
1063                           Register t0,  Register t1,  Register t2,  Register t3,
1064                           bool invertCRC);
1065   void kernel_crc32_2word(Register crc, Register buf, Register len, Register table,
1066                           Register t0,  Register t1,  Register t2,  Register t3,
1067                           bool invertCRC);
1068 
1069   // Emitters for BigInteger.multiplyToLen intrinsic
1070   // note: length of result array (zlen) is passed on the stack
1071  private:
1072   void add2_with_carry(Register dest_hi, Register dest_lo,
1073                        Register src1, Register src2);
1074   void multiply_64_x_64_loop(Register x, Register xstart,
1075                              Register x_xstart,
1076                              Register y, Register y_idx, Register z,
1077                              Register carry, Register product,
1078                              Register idx, Register kdx);
1079   void multiply_add_128_x_128(Register x_xstart, Register y, Register z,
1080                               Register yz_idx, Register idx,
1081                               Register carry, Register product, int offset);
1082   void multiply_128_x_128_loop(Register x_xstart,
1083                                Register y, Register z,
1084                                Register yz_idx, Register idx,
1085                                Register jdx,
1086                                Register carry, Register product,
1087                                Register carry2);
1088  public:
1089   void multiply_to_len(Register x, Register xlen,
1090                        Register y, Register ylen,
1091                        Register z,
1092                        Register tmp1, Register tmp2,
1093                        Register tmp3, Register tmp4, Register tmp5);
1094 };
1095 
1096 /**
1097  * class SkipIfEqual:
1098  *
1099  * Instantiating this class will result in assembly code being output that will
1100  * jump around any code emitted between the creation of the instance and it's
1101  * automatic destruction at the end of a scope block, depending on the value of
1102  * the flag passed to the constructor, which will be checked at run-time.
1103  */
1104 class SkipIfEqual {
1105  private:
1106   MacroAssembler* _masm;
1107   Label _label;
1108 
1109  public:
1110   SkipIfEqual(MacroAssembler*, const bool* flag_addr, bool value, Register _rscratch);
1111   ~SkipIfEqual();
1112 };
1113 
1114 #ifdef ASSERT
1115 // Return false (e.g. important for our impl. of virtual calls).
1116 inline bool AbstractAssembler::pd_check_instruction_mark() { return false; }
1117 #endif
1118 
1119 #endif // CPU_S390_VM_MACROASSEMBLER_S390_HPP