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 *

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 * 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

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package org.graalvm.compiler.lir.amd64;

import static jdk.vm.ci.code.ValueUtil.asStackSlot;

import org.graalvm.compiler.core.common.NumUtil;

import org.graalvm.compiler.core.common.LIRKind;

import org.graalvm.compiler.lir.framemap.FrameMap;

import jdk.vm.ci.amd64.AMD64Kind;

import jdk.vm.ci.code.CodeCacheProvider;

import jdk.vm.ci.code.RegisterConfig;

import jdk.vm.ci.code.StackSlot;

/**

 * AMD64 specific frame map.

 *

 * This is the format of an AMD64 stack frame:

 *

 * <pre>

 *   Base       Contents

 *

 *            :                                :  -----

 *   caller   | incoming overflow argument n   |    ^

 *   frame    :     ...                        :    | positive

 *            | incoming overflow argument 0   |    | offsets

 *   ---------+--------------------------------+---------------------

 *            | return address                 |    |            ^

 *   current  +--------------------------------+    |            |    -----

 *   frame    |                                |    |            |      ^

 *            : callee save area               :    |            |      |

 *            |                                |    |            |      |

 *            +--------------------------------+    |            |      |

 *            | spill slot 0                   |    | negative   |      |

 *            :     ...                        :    v offsets    |      |

 *            | spill slot n                   |  -----        total  frame

 *            +--------------------------------+               frame  size

 *            | alignment padding              |               size     |

 *            +--------------------------------+  -----          |      |

 *            | outgoing overflow argument n   |    ^            |      |

 *            :     ...                        :    | positive   |      |

 *            | outgoing overflow argument 0   |    | offsets    v      v

 *    %sp-->  +--------------------------------+---------------------------

 *

 * </pre>

 *

 * The spill slot area also includes stack allocated memory blocks (ALLOCA blocks). The size of such

 * a block may be greater than the size of a normal spill slot or the word size.

 * <p>

 * A runtime can reserve space at the beginning of the overflow argument area. The calling

 * convention can specify that the first overflow stack argument is not at offset 0, but at a

 * specified offset. Use {@link CodeCacheProvider#getMinimumOutgoingSize()} to make sure that

 * call-free methods also have this space reserved. Then the VM can use the memory at offset 0

 * relative to the stack pointer.

 */

public class AMD64FrameMap extends FrameMap {

    private StackSlot rbpSpillSlot;

        super(codeCache, registerConfig, referenceMapFactory);

        // (negative) offset relative to sp + total frame size

    }

    @Override

    public int totalFrameSize() {

        int result = frameSize() + initialSpillSize;

        assert result % getTarget().stackAlignment == 0 : "Total frame size not aligned: " + result;

        return result;

    }

    @Override

    public int currentFrameSize() {

        return alignFrameSize(outgoingSize + spillSize - initialSpillSize);

    }

    @Override

    protected int alignFrameSize(int size) {

        return NumUtil.roundUp(size + initialSpillSize, getTarget().stackAlignment) - initialSpillSize;

    }

    @Override

    public int offsetForStackSlot(StackSlot slot) {

        // @formatter:off

        assert (!slot.getRawAddFrameSize() && slot.getRawOffset() <  outgoingSize) ||

               (slot.getRawAddFrameSize() && slot.getRawOffset()  <  0 && -slot.getRawOffset() <= spillSize) ||

               (slot.getRawAddFrameSize() && slot.getRawOffset()  >= 0) :

                   String.format("RawAddFrameSize: %b RawOffset: 0x%x spillSize: 0x%x outgoingSize: 0x%x", slot.getRawAddFrameSize(), slot.getRawOffset(), spillSize, outgoingSize);

        // @formatter:on

        return super.offsetForStackSlot(slot);

    }

    /**

     * For non-leaf methods, RBP is preserved in the special stack slot required by the HotSpot

     * runtime for walking/inspecting frames of such methods.

     */

    StackSlot allocateRBPSpillSlot() {

        assert spillSize == initialSpillSize : "RBP spill slot must be the first allocated stack slots";

        rbpSpillSlot = allocateSpillSlot(LIRKind.value(AMD64Kind.QWORD));

        assert asStackSlot(rbpSpillSlot).getRawOffset() == -16 : asStackSlot(rbpSpillSlot).getRawOffset();

        return rbpSpillSlot;

    }

    void freeRBPSpillSlot() {

        int size = spillSlotSize(LIRKind.value(AMD64Kind.QWORD));

        assert spillSize == NumUtil.roundUp(initialSpillSize + size, size) : "RBP spill slot can not be freed after allocation other stack slots";

        spillSize = initialSpillSize;

    }

    public StackSlot allocateDeoptimizationRescueSlot() {

        assert spillSize == initialSpillSize || spillSize == initialSpillSize +

                        spillSlotSize(LIRKind.value(AMD64Kind.QWORD)) : "Deoptimization rescue slot must be the first or second (if there is an RBP spill slot) stack slot";

        return allocateSpillSlot(LIRKind.value(AMD64Kind.QWORD));

    }

}