jdk8-mips64-public/hotspot: src/share/vm/opto/regmask.hpp@c1c199dde5c9 (annotated)

src/share/vm/opto/regmask.hpp@c1c199dde5c9 (annotated)

src/share/vm/opto/regmask.hpp

Wed, 03 Jun 2015 14:22:57 +0200

author: roland
date: Wed, 03 Jun 2015 14:22:57 +0200
changeset 7859: c1c199dde5c9
parent 7598: ddce0b7cee93
child 7994: 04ff2f6cd0eb
permissions: -rw-r--r--

8077504: Unsafe load can loose control dependency and cause crash
Summary: Node::depends_only_on_test() should return false for Unsafe loads
Reviewed-by: kvn, adinn

 /*
  * Copyright (c) 1997, 2015, 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.
  *
  */
 #ifndef SHARE_VM_OPTO_REGMASK_HPP
 #define SHARE_VM_OPTO_REGMASK_HPP
 #include "code/vmreg.hpp"
 #include "libadt/port.hpp"
 #include "opto/optoreg.hpp"
 #if defined ADGLOBALS_MD_HPP
 # include ADGLOBALS_MD_HPP
 #elif defined TARGET_ARCH_MODEL_x86_32
 # include "adfiles/adGlobals_x86_32.hpp"
 #elif defined TARGET_ARCH_MODEL_x86_64
 # include "adfiles/adGlobals_x86_64.hpp"
 #elif defined TARGET_ARCH_MODEL_sparc
 # include "adfiles/adGlobals_sparc.hpp"
 #elif defined TARGET_ARCH_MODEL_zero
 # include "adfiles/adGlobals_zero.hpp"
 #elif defined TARGET_ARCH_MODEL_ppc_64
 # include "adfiles/adGlobals_ppc_64.hpp"
 #endif
 // Some fun naming (textual) substitutions:
 //
 // RegMask::get_low_elem() ==> RegMask::find_first_elem()
 // RegMask::Special        ==> RegMask::Empty
 // RegMask::_flags         ==> RegMask::is_AllStack()
 // RegMask::operator<<=()  ==> RegMask::Insert()
 // RegMask::operator>>=()  ==> RegMask::Remove()
 // RegMask::Union()        ==> RegMask::OR
 // RegMask::Inter()        ==> RegMask::AND
 //
 // OptoRegister::RegName   ==> OptoReg::Name
 //
 // OptoReg::stack0()       ==> _last_Mach_Reg  or ZERO in core version
 //
 // numregs in chaitin      ==> proper degree in chaitin
 //-------------Non-zero bit search methods used by RegMask---------------------
 // Find lowest 1, or return 32 if empty
 int find_lowest_bit( uint32 mask );
 // Find highest 1, or return 32 if empty
 int find_hihghest_bit( uint32 mask );
 //------------------------------RegMask----------------------------------------
 // The ADL file describes how to print the machine-specific registers, as well
 // as any notion of register classes.  We provide a register mask, which is
 // just a collection of Register numbers.
 // The ADLC defines 2 macros, RM_SIZE and FORALL_BODY.
 // RM_SIZE is the size of a register mask in words.
 // FORALL_BODY replicates a BODY macro once per word in the register mask.
 // The usage is somewhat clumsy and limited to the regmask.[h,c]pp files.
 // However, it means the ADLC can redefine the unroll macro and all loops
 // over register masks will be unrolled by the correct amount.
 class RegMask VALUE_OBJ_CLASS_SPEC {
   union {
     double _dummy_force_double_alignment[RM_SIZE>>1];
     // Array of Register Mask bits.  This array is large enough to cover
     // all the machine registers and all parameters that need to be passed
     // on the stack (stack registers) up to some interesting limit.  Methods
     // that need more parameters will NOT be compiled.  On Intel, the limit
     // is something like 90+ parameters.
     int _A[RM_SIZE];
   };
   enum {
     _WordBits    = BitsPerInt,
     _LogWordBits = LogBitsPerInt,
     _RM_SIZE     = RM_SIZE   // local constant, imported, then hidden by #undef
   };
 public:
   enum { CHUNK_SIZE = RM_SIZE*_WordBits };
   // SlotsPerLong is 2, since slots are 32 bits and longs are 64 bits.
   // Also, consider the maximum alignment size for a normally allocated
   // value.  Since we allocate register pairs but not register quads (at
   // present), this alignment is SlotsPerLong (== 2).  A normally
   // aligned allocated register is either a single register, or a pair
   // of adjacent registers, the lower-numbered being even.
   // See also is_aligned_Pairs() below, and the padding added before
   // Matcher::_new_SP to keep allocated pairs aligned properly.
   // If we ever go to quad-word allocations, SlotsPerQuad will become
   // the controlling alignment constraint.  Note that this alignment
   // requirement is internal to the allocator, and independent of any
   // particular platform.
   enum { SlotsPerLong = 2,
          SlotsPerVecS = 1,
          SlotsPerVecD = 2,
          SlotsPerVecX = 4,
          SlotsPerVecY = 8 };
   // A constructor only used by the ADLC output.  All mask fields are filled
   // in directly.  Calls to this look something like RM(1,2,3,4);
   RegMask(
 #   define BODY(I) int a##I,
     FORALL_BODY
 #   undef BODY
     int dummy = 0 ) {
 #   define BODY(I) _A[I] = a##I;
     FORALL_BODY
 #   undef BODY
   }
   // Handy copying constructor
   RegMask( RegMask *rm ) {
 #   define BODY(I) _A[I] = rm->_A[I];
     FORALL_BODY
 #   undef BODY
   }
   // Construct an empty mask
   RegMask( ) { Clear(); }
   // Construct a mask with a single bit
   RegMask( OptoReg::Name reg ) { Clear(); Insert(reg); }
   // Check for register being in mask
   int Member( OptoReg::Name reg ) const {
     assert( reg < CHUNK_SIZE, "" );
     return _A[reg>>_LogWordBits] & (1<<(reg&(_WordBits-1)));
   }
   // The last bit in the register mask indicates that the mask should repeat
   // indefinitely with ONE bits.  Returns TRUE if mask is infinite or
   // unbounded in size.  Returns FALSE if mask is finite size.
   int is_AllStack() const { return _A[RM_SIZE-1] >> (_WordBits-1); }
   // Work around an -xO3 optimization problme in WS6U1. The old way:
   //   void set_AllStack() { _A[RM_SIZE-1] |= (1<<(_WordBits-1)); }
   // will cause _A[RM_SIZE-1] to be clobbered, not updated when set_AllStack()
   // follows an Insert() loop, like the one found in init_spill_mask(). Using
   // Insert() instead works because the index into _A in computed instead of
   // constant.  See bug 4665841.
   void set_AllStack() { Insert(OptoReg::Name(CHUNK_SIZE-1)); }
   // Test for being a not-empty mask.
   int is_NotEmpty( ) const {
     int tmp = 0;
 #   define BODY(I) tmp |= _A[I];
     FORALL_BODY
 #   undef BODY
     return tmp;
   }
   // Find lowest-numbered register from mask, or BAD if mask is empty.
   OptoReg::Name find_first_elem() const {
     int base, bits;
 #   define BODY(I) if( (bits = _A[I]) != 0 ) base = I<<_LogWordBits; else
     FORALL_BODY
 #   undef BODY
       { base = OptoReg::Bad; bits = 1<<0; }
     return OptoReg::Name(base + find_lowest_bit(bits));
   }
   // Get highest-numbered register from mask, or BAD if mask is empty.
   OptoReg::Name find_last_elem() const {
     int base, bits;
 #   define BODY(I) if( (bits = _A[RM_SIZE-1-I]) != 0 ) base = (RM_SIZE-1-I)<<_LogWordBits; else
     FORALL_BODY
 #   undef BODY
       { base = OptoReg::Bad; bits = 1<<0; }
     return OptoReg::Name(base + find_hihghest_bit(bits));
   }
   // Find the lowest-numbered register pair in the mask.  Return the
   // HIGHEST register number in the pair, or BAD if no pairs.
   // Assert that the mask contains only bit pairs.
   OptoReg::Name find_first_pair() const;
   // Clear out partial bits; leave only aligned adjacent bit pairs.
   void clear_to_pairs();
   // Smear out partial bits; leave only aligned adjacent bit pairs.
   void smear_to_pairs();
   // Verify that the mask contains only aligned adjacent bit pairs
   void verify_pairs() const { assert( is_aligned_pairs(), "mask is not aligned, adjacent pairs" ); }
   // Test that the mask contains only aligned adjacent bit pairs
   bool is_aligned_pairs() const;
   // mask is a pair of misaligned registers
   bool is_misaligned_pair() const { return Size()==2 && !is_aligned_pairs(); }
   // Test for single register
   int is_bound1() const;
   // Test for a single adjacent pair
   int is_bound_pair() const;
   // Test for a single adjacent set of ideal register's size.
   int is_bound(uint ireg) const {
     if (is_vector(ireg)) {
       if (is_bound_set(num_registers(ireg)))
         return true;
     } else if (is_bound1() || is_bound_pair()) {
       return true;
     }
     return false;
   }
   // Find the lowest-numbered register set in the mask.  Return the
   // HIGHEST register number in the set, or BAD if no sets.
   // Assert that the mask contains only bit sets.
   OptoReg::Name find_first_set(const int size) const;
   // Clear out partial bits; leave only aligned adjacent bit sets of size.
   void clear_to_sets(const int size);
   // Smear out partial bits to aligned adjacent bit sets.
   void smear_to_sets(const int size);
   // Verify that the mask contains only aligned adjacent bit sets
   void verify_sets(int size) const { assert(is_aligned_sets(size), "mask is not aligned, adjacent sets"); }
   // Test that the mask contains only aligned adjacent bit sets
   bool is_aligned_sets(const int size) const;
   // mask is a set of misaligned registers
   bool is_misaligned_set(int size) const { return (int)Size()==size && !is_aligned_sets(size);}
   // Test for a single adjacent set
   int is_bound_set(const int size) const;
   static bool is_vector(uint ireg);
   static int num_registers(uint ireg);
   // Fast overlap test.  Non-zero if any registers in common.
   int overlap( const RegMask &rm ) const {
     return
 #   define BODY(I) (_A[I] & rm._A[I]) |
     FORALL_BODY
 #   undef BODY
 ;
   }
   // Special test for register pressure based splitting
   // UP means register only, Register plus stack, or stack only is DOWN
   bool is_UP() const;
   // Clear a register mask
   void Clear( ) {
 #   define BODY(I) _A[I] = 0;
     FORALL_BODY
 #   undef BODY
   }
   // Fill a register mask with 1's
   void Set_All( ) {
 #   define BODY(I) _A[I] = -1;
     FORALL_BODY
 #   undef BODY
   }
   // Insert register into mask
   void Insert( OptoReg::Name reg ) {
     assert( reg < CHUNK_SIZE, "" );
     _A[reg>>_LogWordBits] |= (1<<(reg&(_WordBits-1)));
   }
   // Remove register from mask
   void Remove( OptoReg::Name reg ) {
     assert( reg < CHUNK_SIZE, "" );
     _A[reg>>_LogWordBits] &= ~(1<<(reg&(_WordBits-1)));
   }
   // OR 'rm' into 'this'
   void OR( const RegMask &rm ) {
 #   define BODY(I) this->_A[I] |= rm._A[I];
     FORALL_BODY
 #   undef BODY
   }
   // AND 'rm' into 'this'
   void AND( const RegMask &rm ) {
 #   define BODY(I) this->_A[I] &= rm._A[I];
     FORALL_BODY
 #   undef BODY
   }
   // Subtract 'rm' from 'this'
   void SUBTRACT( const RegMask &rm ) {
 #   define BODY(I) _A[I] &= ~rm._A[I];
     FORALL_BODY
 #   undef BODY
   }
   // Compute size of register mask: number of bits
   uint Size() const;
 #ifndef PRODUCT
   void print() const { dump(); }
   void dump(outputStream *st = tty) const; // Print a mask
 #endif
   static const RegMask Empty;   // Common empty mask
   static bool can_represent(OptoReg::Name reg) {
     // NOTE: -1 in computation reflects the usage of the last
     //       bit of the regmask as an infinite stack flag and
     //       -7 is to keep mask aligned for largest value (VecY).
     return (int)reg < (int)(CHUNK_SIZE-1);
   }
   static bool can_represent_arg(OptoReg::Name reg) {
     // NOTE: -SlotsPerVecY in computation reflects the need
     //       to keep mask aligned for largest value (VecY).
     return (int)reg < (int)(CHUNK_SIZE-SlotsPerVecY);
   }
 };
 // Do not use this constant directly in client code!
 #undef RM_SIZE
 #endif // SHARE_VM_OPTO_REGMASK_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/opto/regmask.hpp@c1c199dde5c9 (annotated)

src/share/vm/opto/regmask.hpp