c2_CodeStubs.cpp

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#include "asm/codeBuffer.hpp"
#include "code/codeBlob.hpp"
#include "opto/c2_CodeStubs.hpp"
#include "opto/c2_MacroAssembler.hpp"
#include "opto/compile.hpp"
#include "opto/output.hpp"

C2CodeStubList::C2CodeStubList() :
  _stubs(Compile::current()->comp_arena(), 2, 0, nullptr) {}

void C2CodeStubList::emit(C2_MacroAssembler& masm) {
  for (int i = _stubs.length() - 1; i >= 0; i--) {
    C2CodeStub* stub = _stubs.at(i);
    int max_size = stub->max_size();
    // Make sure there is enough space in the code buffer
    if (masm.code()->insts()->maybe_expand_to_ensure_remaining(max_size) && masm.code()->blob() == nullptr) {
      ciEnv::current()->record_failure("CodeCache is full");
      return;
    }

    DEBUG_ONLY(int size_before = masm.offset();)

    stub->emit(masm);

    DEBUG_ONLY(int actual_size = masm.offset() - size_before;)
    assert(max_size >= actual_size, "Expected stub size (%d) must be larger than or equal to actual stub size (%d)", max_size, actual_size);
  }
}

// move here to avoid circular dependency between c2_CodeStubs.hpp and output.hpp
void C2CodeStub::add_to_stub_list() {
  if (!Compile::current()->output()->in_scratch_emit_size()) {
    Compile::current()->output()->add_stub(this);
  }
}