1.1 --- a/src/share/vm/code/relocInfo.hpp Wed Jul 03 11:50:29 2013 -0700
1.2 +++ b/src/share/vm/code/relocInfo.hpp Thu Jul 04 10:51:31 2013 +0200
1.3 @@ -260,8 +260,8 @@
1.4 poll_type = 10, // polling instruction for safepoints
1.5 poll_return_type = 11, // polling instruction for safepoints at return
1.6 metadata_type = 12, // metadata that used to be oops
1.7 - yet_unused_type_1 = 13, // Still unused
1.8 - yet_unused_type_2 = 14, // Still unused
1.9 + trampoline_stub_type = 13, // stub-entry for trampoline
1.10 + yet_unused_type_1 = 14, // Still unused
1.11 data_prefix_tag = 15, // tag for a prefix (carries data arguments)
1.12 type_mask = 15 // A mask which selects only the above values
1.13 };
1.14 @@ -301,6 +301,7 @@
1.15 visitor(poll) \
1.16 visitor(poll_return) \
1.17 visitor(section_word) \
1.18 + visitor(trampoline_stub) \
1.19
1.20
1.21 public:
1.22 @@ -1150,6 +1151,43 @@
1.23 public:
1.24 };
1.25
1.26 +// Trampoline Relocations.
1.27 +// A trampoline allows to encode a small branch in the code, even if there
1.28 +// is the chance that this branch can not reach all possible code locations.
1.29 +// If the relocation finds that a branch is too far for the instruction
1.30 +// in the code, it can patch it to jump to the trampoline where is
1.31 +// sufficient space for a far branch. Needed on PPC.
1.32 +class trampoline_stub_Relocation : public Relocation {
1.33 + relocInfo::relocType type() { return relocInfo::trampoline_stub_type; }
1.34 +
1.35 + public:
1.36 + static RelocationHolder spec(address static_call) {
1.37 + RelocationHolder rh = newHolder();
1.38 + return (new (rh) trampoline_stub_Relocation(static_call));
1.39 + }
1.40 +
1.41 + private:
1.42 + address _owner; // Address of the NativeCall that owns the trampoline.
1.43 +
1.44 + trampoline_stub_Relocation(address owner) {
1.45 + _owner = owner;
1.46 + }
1.47 +
1.48 + friend class RelocIterator;
1.49 + trampoline_stub_Relocation() { }
1.50 +
1.51 + public:
1.52 +
1.53 + // Return the address of the NativeCall that owns the trampoline.
1.54 + address owner() { return _owner; }
1.55 +
1.56 + void pack_data_to(CodeSection * dest);
1.57 + void unpack_data();
1.58 +
1.59 + // Find the trampoline stub for a call.
1.60 + static address get_trampoline_for(address call, nmethod* code);
1.61 +};
1.62 +
1.63 class external_word_Relocation : public DataRelocation {
1.64 relocInfo::relocType type() { return relocInfo::external_word_type; }
1.65
