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package sun.jvm.hotspot.runtime.x86;

import java.util.*;
import sun.jvm.hotspot.code.*;
import sun.jvm.hotspot.compiler.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.oops.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.types.*;
import sun.jvm.hotspot.utilities.*;
import sun.jvm.hotspot.utilities.Observable;
import sun.jvm.hotspot.utilities.Observer;

Specialization of and implementation of abstract methods of the Frame class for the x86 family of CPUs.
/** Specialization of and implementation of abstract methods of the Frame class for the x86 family of CPUs. */
public class X86Frame extends Frame { private static final boolean DEBUG; static { DEBUG = System.getProperty("sun.jvm.hotspot.runtime.x86.X86Frame.DEBUG") != null; } // All frames private static final int LINK_OFFSET = 0; private static final int RETURN_ADDR_OFFSET = 1; private static final int SENDER_SP_OFFSET = 2; // Interpreter frames private static final int INTERPRETER_FRAME_SENDER_SP_OFFSET = -1; private static final int INTERPRETER_FRAME_LAST_SP_OFFSET = INTERPRETER_FRAME_SENDER_SP_OFFSET - 1; private static final int INTERPRETER_FRAME_METHOD_OFFSET = INTERPRETER_FRAME_LAST_SP_OFFSET - 1; private static int INTERPRETER_FRAME_MIRROR_OFFSET; private static int INTERPRETER_FRAME_MDX_OFFSET; // Non-core builds only private static int INTERPRETER_FRAME_CACHE_OFFSET; private static int INTERPRETER_FRAME_LOCALS_OFFSET; private static int INTERPRETER_FRAME_BCX_OFFSET; private static int INTERPRETER_FRAME_INITIAL_SP_OFFSET; private static int INTERPRETER_FRAME_MONITOR_BLOCK_TOP_OFFSET; private static int INTERPRETER_FRAME_MONITOR_BLOCK_BOTTOM_OFFSET; // Entry frames private static int ENTRY_FRAME_CALL_WRAPPER_OFFSET; private static VMReg rbp; static { VM.registerVMInitializedObserver(new Observer() { public void update(Observable o, Object data) { initialize(VM.getVM().getTypeDataBase()); } }); } private static synchronized void initialize(TypeDataBase db) { INTERPRETER_FRAME_MIRROR_OFFSET = INTERPRETER_FRAME_METHOD_OFFSET - 1; INTERPRETER_FRAME_MDX_OFFSET = INTERPRETER_FRAME_MIRROR_OFFSET - 1; INTERPRETER_FRAME_CACHE_OFFSET = INTERPRETER_FRAME_MDX_OFFSET - 1; INTERPRETER_FRAME_LOCALS_OFFSET = INTERPRETER_FRAME_CACHE_OFFSET - 1; INTERPRETER_FRAME_BCX_OFFSET = INTERPRETER_FRAME_LOCALS_OFFSET - 1; INTERPRETER_FRAME_INITIAL_SP_OFFSET = INTERPRETER_FRAME_BCX_OFFSET - 1; INTERPRETER_FRAME_MONITOR_BLOCK_TOP_OFFSET = INTERPRETER_FRAME_INITIAL_SP_OFFSET; INTERPRETER_FRAME_MONITOR_BLOCK_BOTTOM_OFFSET = INTERPRETER_FRAME_INITIAL_SP_OFFSET; ENTRY_FRAME_CALL_WRAPPER_OFFSET = db.lookupIntConstant("frame::entry_frame_call_wrapper_offset"); if (VM.getVM().getAddressSize() == 4) { rbp = new VMReg(5); } else { rbp = new VMReg(5 << 1); } } // an additional field beyond sp and pc: Address raw_fp; // frame pointer private Address raw_unextendedSP; private Address live_bcp; private X86Frame() { } private void adjustForDeopt() { if ( pc != null) { // Look for a deopt pc and if it is deopted convert to original pc CodeBlob cb = VM.getVM().getCodeCache().findBlob(pc); if (cb != null && cb.isJavaMethod()) { NMethod nm = (NMethod) cb; if (pc.equals(nm.deoptHandlerBegin())) { if (Assert.ASSERTS_ENABLED) { Assert.that(this.getUnextendedSP() != null, "null SP in Java frame"); } // adjust pc if frame is deoptimized. pc = this.getUnextendedSP().getAddressAt(nm.origPCOffset()); deoptimized = true; } } } } private void initFrame(Address raw_sp, Address raw_fp, Address pc, Address raw_unextendedSp, Address live_bcp) { this.raw_sp = raw_sp; this.raw_fp = raw_fp; if (raw_unextendedSp == null) { this.raw_unextendedSP = raw_sp; } else { this.raw_unextendedSP = raw_unextendedSp; } if (pc == null) { this.pc = raw_sp.getAddressAt(-1 * VM.getVM().getAddressSize()); } else { this.pc = pc; } this.live_bcp = live_bcp; adjustUnextendedSP(); // Frame must be fully constructed before this call adjustForDeopt(); } public X86Frame(Address raw_sp, Address raw_fp, Address pc) { initFrame(raw_sp, raw_fp, pc, null, null); if (DEBUG) { System.out.println("X86Frame(sp, fp, pc): " + this); dumpStack(); } } public X86Frame(Address raw_sp, Address raw_fp) { initFrame(raw_sp, raw_fp, null, null, null); if (DEBUG) { System.out.println("X86Frame(sp, fp): " + this); dumpStack(); } } public X86Frame(Address raw_sp, Address raw_unextendedSp, Address raw_fp, Address pc) { initFrame(raw_sp, raw_fp, pc, raw_unextendedSp, null); if (DEBUG) { System.out.println("X86Frame(sp, unextendedSP, fp, pc): " + this); dumpStack(); } } public X86Frame(Address raw_sp, Address raw_fp, Address pc, Address raw_unextendedSp, Address live_bcp) { initFrame(raw_sp, raw_fp, pc, raw_unextendedSp, live_bcp); if (DEBUG) { System.out.println("X86Frame(sp, fp, pc, unextendedSP, live_bcp): " + this); dumpStack(); } } public Object clone() { X86Frame frame = new X86Frame(); frame.raw_sp = raw_sp; frame.raw_unextendedSP = raw_unextendedSP; frame.raw_fp = raw_fp; frame.pc = pc; frame.deoptimized = deoptimized; frame.live_bcp = live_bcp; return frame; } public boolean equals(Object arg) { if (arg == null) { return false; } if (!(arg instanceof X86Frame)) { return false; } X86Frame other = (X86Frame) arg; return (AddressOps.equal(getSP(), other.getSP()) && AddressOps.equal(getUnextendedSP(), other.getUnextendedSP()) && AddressOps.equal(getFP(), other.getFP()) && AddressOps.equal(getPC(), other.getPC())); } public int hashCode() { if (raw_sp == null) { return 0; } return raw_sp.hashCode(); } public String toString() { return "sp: " + (getSP() == null? "null" : getSP().toString()) + ", unextendedSP: " + (getUnextendedSP() == null? "null" : getUnextendedSP().toString()) + ", fp: " + (getFP() == null? "null" : getFP().toString()) + ", pc: " + (pc == null? "null" : pc.toString()); } // accessors for the instance variables public Address getFP() { return raw_fp; } public Address getSP() { return raw_sp; } public Address getID() { return raw_sp; } // FIXME: not implemented yet (should be done for Solaris/X86) public boolean isSignalHandlerFrameDbg() { return false; } public int getSignalNumberDbg() { return 0; } public String getSignalNameDbg() { return null; } public boolean isInterpretedFrameValid() { if (Assert.ASSERTS_ENABLED) { Assert.that(isInterpretedFrame(), "Not an interpreted frame"); } // These are reasonable sanity checks if (getFP() == null || getFP().andWithMask(0x3) != null) { return false; } if (getSP() == null || getSP().andWithMask(0x3) != null) { return false; } if (getFP().addOffsetTo(INTERPRETER_FRAME_INITIAL_SP_OFFSET * VM.getVM().getAddressSize()).lessThan(getSP())) { return false; } // These are hacks to keep us out of trouble. // The problem with these is that they mask other problems if (getFP().lessThanOrEqual(getSP())) { // this attempts to deal with unsigned comparison above return false; } if (getFP().minus(getSP()) > 4096 * VM.getVM().getAddressSize()) { // stack frames shouldn't be large. return false; } return true; } // FIXME: not applicable in current system // void patch_pc(Thread* thread, address pc); public Frame sender(RegisterMap regMap, CodeBlob cb) { X86RegisterMap map = (X86RegisterMap) regMap; if (Assert.ASSERTS_ENABLED) { Assert.that(map != null, "map must be set"); } // Default is we done have to follow them. The sender_for_xxx will // update it accordingly map.setIncludeArgumentOops(false); if (isEntryFrame()) return senderForEntryFrame(map); if (isInterpretedFrame()) return senderForInterpreterFrame(map); if(cb == null) { cb = VM.getVM().getCodeCache().findBlob(getPC()); } else { if (Assert.ASSERTS_ENABLED) { Assert.that(cb.equals(VM.getVM().getCodeCache().findBlob(getPC())), "Must be the same"); } } if (cb != null) { return senderForCompiledFrame(map, cb); } // Must be native-compiled frame, i.e. the marshaling code for native // methods that exists in the core system. return new X86Frame(getSenderSP(), getLink(), getSenderPC()); } private Frame senderForEntryFrame(X86RegisterMap map) { if (DEBUG) { System.out.println("senderForEntryFrame"); } if (Assert.ASSERTS_ENABLED) { Assert.that(map != null, "map must be set"); } // Java frame called from C; skip all C frames and return top C // frame of that chunk as the sender X86JavaCallWrapper jcw = (X86JavaCallWrapper) getEntryFrameCallWrapper(); if (Assert.ASSERTS_ENABLED) { Assert.that(!entryFrameIsFirst(), "next Java fp must be non zero"); Assert.that(jcw.getLastJavaSP().greaterThan(getSP()), "must be above this frame on stack"); } X86Frame fr; if (jcw.getLastJavaPC() != null) { fr = new X86Frame(jcw.getLastJavaSP(), jcw.getLastJavaFP(), jcw.getLastJavaPC()); } else { fr = new X86Frame(jcw.getLastJavaSP(), jcw.getLastJavaFP()); } map.clear(); if (Assert.ASSERTS_ENABLED) { Assert.that(map.getIncludeArgumentOops(), "should be set by clear"); } return fr; } //------------------------------------------------------------------------------ // frame::adjust_unextended_sp private void adjustUnextendedSP() { // On x86, sites calling method handle intrinsics and lambda forms are treated // as any other call site. Therefore, no special action is needed when we are // returning to any of these call sites. CodeBlob cb = cb(); NMethod senderNm = (cb == null) ? null : cb.asNMethodOrNull(); if (senderNm != null) { // If the sender PC is a deoptimization point, get the original PC. if (senderNm.isDeoptEntry(getPC()) || senderNm.isDeoptMhEntry(getPC())) { // DEBUG_ONLY(verifyDeoptriginalPc(senderNm, raw_unextendedSp)); } } } private Frame senderForInterpreterFrame(X86RegisterMap map) { if (DEBUG) { System.out.println("senderForInterpreterFrame"); } Address unextendedSP = addressOfStackSlot(INTERPRETER_FRAME_SENDER_SP_OFFSET).getAddressAt(0); Address sp = addressOfStackSlot(SENDER_SP_OFFSET); // We do not need to update the callee-save register mapping because above // us is either another interpreter frame or a converter-frame, but never // directly a compiled frame. // 11/24/04 SFG. With the removal of adapter frames this is no longer true. // However c2 no longer uses callee save register for java calls so there // are no callee register to find. if (map.getUpdateMap()) updateMapWithSavedLink(map, addressOfStackSlot(LINK_OFFSET)); return new X86Frame(sp, unextendedSP, getLink(), getSenderPC()); } private void updateMapWithSavedLink(RegisterMap map, Address savedFPAddr) { map.setLocation(rbp, savedFPAddr); } private Frame senderForCompiledFrame(X86RegisterMap map, CodeBlob cb) { if (DEBUG) { System.out.println("senderForCompiledFrame"); } // // NOTE: some of this code is (unfortunately) duplicated in X86CurrentFrameGuess // if (Assert.ASSERTS_ENABLED) { Assert.that(map != null, "map must be set"); } // frame owned by optimizing compiler if (Assert.ASSERTS_ENABLED) { Assert.that(cb.getFrameSize() >= 0, "must have non-zero frame size"); } Address senderSP = getUnextendedSP().addOffsetTo(cb.getFrameSize()); // On Intel the return_address is always the word on the stack Address senderPC = senderSP.getAddressAt(-1 * VM.getVM().getAddressSize()); // This is the saved value of EBP which may or may not really be an FP. // It is only an FP if the sender is an interpreter frame (or C1?). Address savedFPAddr = senderSP.addOffsetTo(- SENDER_SP_OFFSET * VM.getVM().getAddressSize()); if (map.getUpdateMap()) { // Tell GC to use argument oopmaps for some runtime stubs that need it. // For C1, the runtime stub might not have oop maps, so set this flag // outside of update_register_map. map.setIncludeArgumentOops(cb.callerMustGCArguments()); if (cb.getOopMaps() != null) { ImmutableOopMapSet.updateRegisterMap(this, cb, map, true); } // Since the prolog does the save and restore of EBP there is no oopmap // for it so we must fill in its location as if there was an oopmap entry // since if our caller was compiled code there could be live jvm state in it. updateMapWithSavedLink(map, savedFPAddr); } return new X86Frame(senderSP, savedFPAddr.getAddressAt(0), senderPC); } protected boolean hasSenderPD() { // FIXME // Check for null ebp? Need to do some tests. return true; } public long frameSize() { return (getSenderSP().minus(getSP()) / VM.getVM().getAddressSize()); } public Address getLink() { return addressOfStackSlot(LINK_OFFSET).getAddressAt(0); } public Address getUnextendedSP() { return raw_unextendedSP; } // Return address: public Address getSenderPCAddr() { return addressOfStackSlot(RETURN_ADDR_OFFSET); } public Address getSenderPC() { return getSenderPCAddr().getAddressAt(0); } public Address getSenderSP() { return addressOfStackSlot(SENDER_SP_OFFSET); } public Address addressOfInterpreterFrameLocals() { return addressOfStackSlot(INTERPRETER_FRAME_LOCALS_OFFSET); } private Address addressOfInterpreterFrameBCX() { return addressOfStackSlot(INTERPRETER_FRAME_BCX_OFFSET); } public Address getInterpreterFrameBCP() { // FIXME: this is not atomic with respect to GC and is unsuitable // for use in a non-debugging, or reflective, system. Need to // figure out how to express this. Method method = getInterpreterFrameMethod(); Address bcp = addressOfInterpreterFrameBCX().getAddressAt(0); // If we are in the top level frame then the bcp may have been set for us. If so then let it // take priority. If we are in a top level interpreter frame, the bcp is live in R13 (on x86_64) // and not saved in the BCX stack slot. if (live_bcp != null) { // Only use live_bcp if it points within the Method's bytecodes. Sometimes R13 is used // for scratch purposes and is not a valid BCP. If it is not valid, then we stick with // the bcp stored in the frame, which R13 should have been flushed to. if (method.getConstMethod().isAddressInMethod(live_bcp)) { bcp = live_bcp; } } return bcp; } public int getInterpreterFrameBCI() { Address bcp = getInterpreterFrameBCP(); Method method = getInterpreterFrameMethod(); return bcpToBci(bcp, method); } public Address addressOfInterpreterFrameMDX() { return addressOfStackSlot(INTERPRETER_FRAME_MDX_OFFSET); } // FIXME //inline int frame::interpreter_frame_monitor_size() { // return BasicObjectLock::size(); //} // expression stack // (the max_stack arguments are used by the GC; see class FrameClosure) public Address addressOfInterpreterFrameExpressionStack() { Address monitorEnd = interpreterFrameMonitorEnd().address(); return monitorEnd.addOffsetTo(-1 * VM.getVM().getAddressSize()); } public int getInterpreterFrameExpressionStackDirection() { return -1; } // top of expression stack public Address addressOfInterpreterFrameTOS() { return getSP(); }
Expression stack from top down
/** Expression stack from top down */
public Address addressOfInterpreterFrameTOSAt(int slot) { return addressOfInterpreterFrameTOS().addOffsetTo(slot * VM.getVM().getAddressSize()); } public Address getInterpreterFrameSenderSP() { if (Assert.ASSERTS_ENABLED) { Assert.that(isInterpretedFrame(), "interpreted frame expected"); } return addressOfStackSlot(INTERPRETER_FRAME_SENDER_SP_OFFSET).getAddressAt(0); } // Monitors public BasicObjectLock interpreterFrameMonitorBegin() { return new BasicObjectLock(addressOfStackSlot(INTERPRETER_FRAME_MONITOR_BLOCK_BOTTOM_OFFSET)); } public BasicObjectLock interpreterFrameMonitorEnd() { Address result = addressOfStackSlot(INTERPRETER_FRAME_MONITOR_BLOCK_TOP_OFFSET).getAddressAt(0); if (Assert.ASSERTS_ENABLED) { // make sure the pointer points inside the frame Assert.that(AddressOps.gt(getFP(), result), "result must < than frame pointer"); Assert.that(AddressOps.lte(getSP(), result), "result must >= than stack pointer"); } return new BasicObjectLock(result); } public int interpreterFrameMonitorSize() { return BasicObjectLock.size(); } // Method public Address addressOfInterpreterFrameMethod() { return addressOfStackSlot(INTERPRETER_FRAME_METHOD_OFFSET); } // Constant pool cache public Address addressOfInterpreterFrameCPCache() { return addressOfStackSlot(INTERPRETER_FRAME_CACHE_OFFSET); } // Entry frames public JavaCallWrapper getEntryFrameCallWrapper() { return new X86JavaCallWrapper(addressOfStackSlot(ENTRY_FRAME_CALL_WRAPPER_OFFSET).getAddressAt(0)); } protected Address addressOfSavedOopResult() { // offset is 2 for compiler2 and 3 for compiler1 return getSP().addOffsetTo((VM.getVM().isClientCompiler() ? 2 : 3) * VM.getVM().getAddressSize()); } protected Address addressOfSavedReceiver() { return getSP().addOffsetTo(-4 * VM.getVM().getAddressSize()); } private void dumpStack() { if (getFP() != null) { for (Address addr = getSP().addOffsetTo(-5 * VM.getVM().getAddressSize()); AddressOps.lte(addr, getFP().addOffsetTo(5 * VM.getVM().getAddressSize())); addr = addr.addOffsetTo(VM.getVM().getAddressSize())) { System.out.println(addr + ": " + addr.getAddressAt(0)); } } else { for (Address addr = getSP().addOffsetTo(-5 * VM.getVM().getAddressSize()); AddressOps.lte(addr, getSP().addOffsetTo(20 * VM.getVM().getAddressSize())); addr = addr.addOffsetTo(VM.getVM().getAddressSize())) { System.out.println(addr + ": " + addr.getAddressAt(0)); } } } }