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package org.graalvm.compiler.hotspot;

import org.graalvm.compiler.core.common.spi.ForeignCallLinkage;
import org.graalvm.compiler.core.target.Backend;
import org.graalvm.compiler.hotspot.stubs.Stub;
import jdk.internal.vm.compiler.word.LocationIdentity;

import jdk.vm.ci.meta.InvokeTarget;

The details required to link a HotSpot runtime or stub call.
/**
 * The details required to link a HotSpot runtime or stub call.
 */
public interface HotSpotForeignCallLinkage extends ForeignCallLinkage, InvokeTarget {

    
Constants for specifying whether a foreign call destroys or preserves registers. A foreign call will always destroy its temporary registers. /**
     * Constants for specifying whether a foreign call destroys or preserves registers. A foreign
     * call will always destroy {@link HotSpotForeignCallLinkage#getOutgoingCallingConvention() its}
     * {@linkplain ForeignCallLinkage#getTemporaries() temporary} registers.
     */
    enum RegisterEffect {
        DESTROYS_ALL_CALLER_SAVE_REGISTERS,
        COMPUTES_REGISTERS_KILLED
    }

    
Constants for specifying whether a call is a leaf or not and whether a JavaFrameAnchor prologue and epilogue is required around the call. A leaf function does not lock, GC or throw exceptions. /**
     * Constants for specifying whether a call is a leaf or not and whether a
     * {@code JavaFrameAnchor} prologue and epilogue is required around the call. A leaf function
     * does not lock, GC or throw exceptions.
     */
    enum Transition {
        
A call to a leaf function that is guaranteed to not use floating point registers. Consequently, floating point registers cleanup will be waived. On AMD64, this means the compiler will no longer emit vzeroupper instruction around the foreign call, which it normally does for unknown foreign calls to avoid potential SSE-AVX transition penalty. Besides, this foreign call will never have its caller stack inspected by the VM. That is, JavaFrameAnchor management around the call can be omitted. /**
         * A call to a leaf function that is guaranteed to not use floating point registers.
         * Consequently, floating point registers cleanup will be waived. On AMD64, this means the
         * compiler will no longer emit vzeroupper instruction around the foreign call, which it
         * normally does for unknown foreign calls to avoid potential SSE-AVX transition penalty.
         * Besides, this foreign call will never have its caller stack inspected by the VM. That is,
         * {@code JavaFrameAnchor} management around the call can be omitted.
         */
        LEAF_NO_VZERO,

        
A call to a leaf function that might use floating point registers but will never have its caller stack inspected. That is, JavaFrameAnchor management around the call can be omitted. /**
         * A call to a leaf function that might use floating point registers but will never have its
         * caller stack inspected. That is, {@code JavaFrameAnchor} management around the call can
         * be omitted.
         */
        LEAF,

        
A call to a leaf function that might use floating point registers and may have its caller stack inspected. That is, JavaFrameAnchor management code around the call is required. /**
         * A call to a leaf function that might use floating point registers and may have its caller
         * stack inspected. That is, {@code JavaFrameAnchor} management code around the call is
         * required.
         */
        STACK_INSPECTABLE_LEAF,

        
A function that may lock, GC or raise an exception and thus requires debug info to be associated with a call site to the function. The execution stack may be inspected while in the called function. That is, JavaFrameAnchor management code around the call is required. /**
         * A function that may lock, GC or raise an exception and thus requires debug info to be
         * associated with a call site to the function. The execution stack may be inspected while
         * in the called function. That is, {@code JavaFrameAnchor} management code around the call
         * is required.
         */
        SAFEPOINT,
    }

    
Constants specifying when a foreign call or stub call is re-executable.
/**
     * Constants specifying when a foreign call or stub call is re-executable.
     */
    enum Reexecutability {
        
Denotes a call that cannot be re-executed. If an exception is raised, the call is
deoptimized and the exception is passed on to be dispatched. If the call can throw an
exception it needs to have a precise frame state.
/**
         * Denotes a call that cannot be re-executed. If an exception is raised, the call is
         * deoptimized and the exception is passed on to be dispatched. If the call can throw an
         * exception it needs to have a precise frame state.
         */
        NOT_REEXECUTABLE,

        
Denotes a call that can always be re-executed. If an exception is raised by the call it
may be cleared, compiled code deoptimized and reexecuted. Since the call has no side
effects it is assumed that the same exception will be thrown.
/**
         * Denotes a call that can always be re-executed. If an exception is raised by the call it
         * may be cleared, compiled code deoptimized and reexecuted. Since the call has no side
         * effects it is assumed that the same exception will be thrown.
         */
        REEXECUTABLE
    }

    
Sentinel marker for a computed jump address.
/**
     * Sentinel marker for a computed jump address.
     */
    long JUMP_ADDRESS = 0xDEADDEADBEEFBEEFL;

    
Determines if the call has side effects.
/**
     * Determines if the call has side effects.
     */
    boolean isReexecutable();

    LocationIdentity[] getKilledLocations();

    void setCompiledStub(Stub stub);

    RegisterEffect getEffect();

    
Determines if this is a call to a compiled stub. /**
     * Determines if this is a call to a compiled {@linkplain Stub stub}.
     */
    boolean isCompiledStub();

    
Gets the stub, if any, this foreign call links to.
/**
     * Gets the stub, if any, this foreign call links to.
     */
    Stub getStub();

    void finalizeAddress(Backend backend);

    long getAddress();

    
Determines if the runtime function or stub might use floating point registers. If the answer
is no, then no FPU state management prologue or epilogue needs to be emitted around the call.
/**
     * Determines if the runtime function or stub might use floating point registers. If the answer
     * is no, then no FPU state management prologue or epilogue needs to be emitted around the call.
     */
    boolean mayContainFP();

    
Determines if a JavaFrameAnchor needs to be set up and torn down around this call. /**
     * Determines if a {@code JavaFrameAnchor} needs to be set up and torn down around this call.
     */
    boolean needsJavaFrameAnchor();

    
Gets the VM symbol associated with the target address of the call. /**
     * Gets the VM symbol associated with the target {@linkplain #getAddress() address} of the call.
     */
    String getSymbol();

    
Identifies foreign calls which are guaranteed to include a safepoint check.
/**
     * Identifies foreign calls which are guaranteed to include a safepoint check.
     */
    boolean isGuaranteedSafepoint();
}