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8017308: Remove unused breakpoint relocation type

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Remove unused breakpoint relocation type

Reviewed-by: kvn
This commit is contained in:
Goetz Lindenmaier 2013-06-24 11:53:54 -07:00
parent 1dc7a25eac
commit fad60d1428
7 changed files with 3 additions and 349 deletions
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126
hotspot/src/share/vm/code/relocInfo.hpp
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@ -49,9 +49,6 @@ class NativeMovConstReg;
// RelocIterator
// A StackObj which iterates over the relocations associated with
// a range of code addresses. Can be used to operate a copy of code.
// PatchingRelocIterator
// Specialized subtype of RelocIterator which removes breakpoints
// temporarily during iteration, then restores them.
// BoundRelocation
// An _internal_ type shared by packers and unpackers of relocations.
// It pastes together a RelocationHolder with some pointers into
@ -204,15 +201,6 @@ class NativeMovConstReg;
// immediate field must not straddle a unit of memory coherence.
// //%note reloc_3
//
// relocInfo::breakpoint_type -- a conditional breakpoint in the code
// Value: none
// Instruction types: any whatsoever
// Data: [b [T]t i...]
// The b is a bit-packed word representing the breakpoint's attributes.
// The t is a target address which the breakpoint calls (when it is enabled).
// The i... is a place to store one or two instruction words overwritten
// by a trap, so that the breakpoint may be subsequently removed.
//
// relocInfo::static_stub_type -- an extra stub for each static_call_type
// Value: none
// Instruction types: a virtual call: { set_oop; jump; }
@ -271,8 +259,8 @@ class relocInfo VALUE_OBJ_CLASS_SPEC {
section_word_type = 9, // internal, but a cross-section reference
poll_type = 10, // polling instruction for safepoints
poll_return_type = 11, // polling instruction for safepoints at return
breakpoint_type = 12, // an initialization barrier or safepoint
metadata_type = 13, // metadata that used to be oops
metadata_type = 12, // metadata that used to be oops
yet_unused_type_1 = 13, // Still unused
yet_unused_type_2 = 14, // Still unused
data_prefix_tag = 15, // tag for a prefix (carries data arguments)
type_mask = 15 // A mask which selects only the above values
@ -312,7 +300,6 @@ class relocInfo VALUE_OBJ_CLASS_SPEC {
visitor(internal_word) \
visitor(poll) \
visitor(poll_return) \
visitor(breakpoint) \
visitor(section_word) \
@ -454,7 +441,7 @@ class relocInfo VALUE_OBJ_CLASS_SPEC {
public:
enum {
// Conservatively large estimate of maximum length (in shorts)
// of any relocation record (probably breakpoints are largest).
// of any relocation record.
// Extended format is length prefix, data words, and tag/offset suffix.
length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1,
have_format = format_width > 0
@ -571,8 +558,6 @@ class RelocIterator : public StackObj {
void initialize(nmethod* nm, address begin, address limit);
friend class PatchingRelocIterator;
// make an uninitialized one, for PatchingRelocIterator:
RelocIterator() { initialize_misc(); }
public:
@ -779,9 +764,6 @@ class Relocation VALUE_OBJ_CLASS_SPEC {
void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); }
address pd_call_destination (address orig_addr = NULL);
void pd_set_call_destination (address x);
void pd_swap_in_breakpoint (address x, short* instrs, int instrlen);
void pd_swap_out_breakpoint (address x, short* instrs, int instrlen);
static int pd_breakpoint_size ();
// this extracts the address of an address in the code stream instead of the reloc data
address* pd_address_in_code ();
@ -1302,87 +1284,6 @@ class poll_return_Relocation : public Relocation {
void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
};
class breakpoint_Relocation : public Relocation {
relocInfo::relocType type() { return relocInfo::breakpoint_type; }
enum {
// attributes which affect the interpretation of the data:
removable_attr = 0x0010, // buffer [i...] allows for undoing the trap
internal_attr = 0x0020, // the target is an internal addr (local stub)
settable_attr = 0x0040, // the target is settable
// states which can change over time:
enabled_state = 0x0100, // breakpoint must be active in running code
active_state = 0x0200, // breakpoint instruction actually in code
kind_mask = 0x000F, // mask for extracting kind
high_bit = 0x4000 // extra bit which is always set
};
public:
enum {
// kinds:
initialization = 1,
safepoint = 2
};
// If target is NULL, 32 bits are reserved for a later set_target().
static RelocationHolder spec(int kind, address target = NULL, bool internal_target = false) {
RelocationHolder rh = newHolder();
new(rh) breakpoint_Relocation(kind, target, internal_target);
return rh;
}
private:
// We require every bits value to NOT to fit into relocInfo::datalen_width,
// because we are going to actually store state in the reloc, and so
// cannot allow it to be compressed (and hence copied by the iterator).
short _bits; // bit-encoded kind, attrs, & state
address _target;
breakpoint_Relocation(int kind, address target, bool internal_target);
friend class RelocIterator;
breakpoint_Relocation() { }
short bits() const { return _bits; }
short& live_bits() const { return data()[0]; }
short* instrs() const { return data() + datalen() - instrlen(); }
int instrlen() const { return removable() ? pd_breakpoint_size() : 0; }
void set_bits(short x) {
assert(live_bits() == _bits, "must be the only mutator of reloc info");
live_bits() = _bits = x;
}
public:
address target() const;
void set_target(address x);
int kind() const { return bits() & kind_mask; }
bool enabled() const { return (bits() & enabled_state) != 0; }
bool active() const { return (bits() & active_state) != 0; }
bool internal() const { return (bits() & internal_attr) != 0; }
bool removable() const { return (bits() & removable_attr) != 0; }
bool settable() const { return (bits() & settable_attr) != 0; }
void set_enabled(bool b); // to activate, you must also say set_active
void set_active(bool b); // actually inserts bpt (must be enabled 1st)
// data is packed as 16 bits, followed by the target (1 or 2 words), followed
// if necessary by empty storage for saving away original instruction bytes.
void pack_data_to(CodeSection* dest);
void unpack_data();
// during certain operations, breakpoints must be out of the way:
void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
assert(!active(), "cannot perform relocation on enabled breakpoints");
}
};
// We know all the xxx_Relocation classes, so now we can define these:
#define EACH_CASE(name) \
inline name##_Relocation* RelocIterator::name##_reloc() { \
@ -1401,25 +1302,4 @@ inline RelocIterator::RelocIterator(nmethod* nm, address begin, address limit) {
initialize(nm, begin, limit);
}
// if you are going to patch code, you should use this subclass of
// RelocIterator
class PatchingRelocIterator : public RelocIterator {
private:
RelocIterator _init_state;
void prepass(); // deactivates all breakpoints
void postpass(); // reactivates all enabled breakpoints
// do not copy these puppies; it would have unpredictable side effects
// these are private and have no bodies defined because they should not be called
PatchingRelocIterator(const RelocIterator&);
void operator=(const RelocIterator&);
public:
PatchingRelocIterator(nmethod* nm, address begin = NULL, address limit = NULL)
: RelocIterator(nm, begin, limit) { prepass(); }
~PatchingRelocIterator() { postpass(); }
};
#endif // SHARE_VM_CODE_RELOCINFO_HPP