src/hotspot/cpu/x86/runtime_x86_32.cpp
changeset 47216 71c04702a3d5
parent 40644 39e631ed7145
child 49449 ef5d5d343e2a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/cpu/x86/runtime_x86_32.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 1998, 2016, 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#ifdef COMPILER2
+#include "asm/macroAssembler.hpp"
+#include "asm/macroAssembler.inline.hpp"
+#include "classfile/systemDictionary.hpp"
+#include "code/vmreg.hpp"
+#include "interpreter/interpreter.hpp"
+#include "memory/resourceArea.hpp"
+#include "opto/runtime.hpp"
+#include "runtime/interfaceSupport.hpp"
+#include "runtime/sharedRuntime.hpp"
+#include "runtime/stubRoutines.hpp"
+#include "runtime/vframeArray.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "vmreg_x86.inline.hpp"
+#endif
+
+
+#define __ masm->
+
+//------------------------------generate_exception_blob---------------------------
+// creates exception blob at the end
+// Using exception blob, this code is jumped from a compiled method.
+//
+// Given an exception pc at a call we call into the runtime for the
+// handler in this method. This handler might merely restore state
+// (i.e. callee save registers) unwind the frame and jump to the
+// exception handler for the nmethod if there is no Java level handler
+// for the nmethod.
+//
+// This code is entered with a jmp.
+//
+// Arguments:
+//   rax: exception oop
+//   rdx: exception pc
+//
+// Results:
+//   rax: exception oop
+//   rdx: exception pc in caller or ???
+//   destination: exception handler of caller
+//
+// Note: the exception pc MUST be at a call (precise debug information)
+//       Only register rax, rdx, rcx are not callee saved.
+//
+
+void OptoRuntime::generate_exception_blob() {
+
+  // Capture info about frame layout
+  enum layout {
+    thread_off,                 // last_java_sp
+    // The frame sender code expects that rbp will be in the "natural" place and
+    // will override any oopMap setting for it. We must therefore force the layout
+    // so that it agrees with the frame sender code.
+    rbp_off,
+    return_off,                 // slot for return address
+    framesize
+  };
+
+  // allocate space for the code
+  ResourceMark rm;
+  // setup code generation tools
+  CodeBuffer   buffer("exception_blob", 512, 512);
+  MacroAssembler* masm = new MacroAssembler(&buffer);
+
+  OopMapSet *oop_maps = new OopMapSet();
+
+  address start = __ pc();
+
+  __ push(rdx);
+  __ subptr(rsp, return_off * wordSize);   // Prolog!
+
+  // rbp, location is implicitly known
+  __ movptr(Address(rsp,rbp_off  *wordSize), rbp);
+
+  // Store exception in Thread object. We cannot pass any arguments to the
+  // handle_exception call, since we do not want to make any assumption
+  // about the size of the frame where the exception happened in.
+  __ get_thread(rcx);
+  __ movptr(Address(rcx, JavaThread::exception_oop_offset()), rax);
+  __ movptr(Address(rcx, JavaThread::exception_pc_offset()),  rdx);
+
+  // This call does all the hard work.  It checks if an exception handler
+  // exists in the method.
+  // If so, it returns the handler address.
+  // If not, it prepares for stack-unwinding, restoring the callee-save
+  // registers of the frame being removed.
+  //
+  __ movptr(Address(rsp, thread_off * wordSize), rcx); // Thread is first argument
+  __ set_last_Java_frame(rcx, noreg, noreg, NULL);
+
+  __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, OptoRuntime::handle_exception_C)));
+
+  // No registers to map, rbp is known implicitly
+  oop_maps->add_gc_map( __ pc() - start,  new OopMap( framesize, 0 ));
+  __ get_thread(rcx);
+  __ reset_last_Java_frame(rcx, false);
+
+  // Restore callee-saved registers
+  __ movptr(rbp, Address(rsp, rbp_off * wordSize));
+
+  __ addptr(rsp, return_off * wordSize);   // Epilog!
+  __ pop(rdx); // Exception pc
+
+  // rax: exception handler for given <exception oop/exception pc>
+
+  // We have a handler in rax, (could be deopt blob)
+  // rdx - throwing pc, deopt blob will need it.
+
+  __ push(rax);
+
+  // Get the exception
+  __ movptr(rax, Address(rcx, JavaThread::exception_oop_offset()));
+  // Get the exception pc in case we are deoptimized
+  __ movptr(rdx, Address(rcx, JavaThread::exception_pc_offset()));
+#ifdef ASSERT
+  __ movptr(Address(rcx, JavaThread::exception_handler_pc_offset()), NULL_WORD);
+  __ movptr(Address(rcx, JavaThread::exception_pc_offset()), NULL_WORD);
+#endif
+  // Clear the exception oop so GC no longer processes it as a root.
+  __ movptr(Address(rcx, JavaThread::exception_oop_offset()), NULL_WORD);
+
+  __ pop(rcx);
+
+  // rax: exception oop
+  // rcx: exception handler
+  // rdx: exception pc
+  __ jmp (rcx);
+
+  // -------------
+  // make sure all code is generated
+  masm->flush();
+
+  _exception_blob = ExceptionBlob::create(&buffer, oop_maps, framesize);
+}