+ * 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--> +--------------------------------+--------------------------- + * + *+ * + * 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. + *
+ * 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; + + public AMD64FrameMap(CodeCacheProvider codeCache, RegisterConfig registerConfig, ReferenceMapBuilderFactory referenceMapFactory) { + super(codeCache, registerConfig, referenceMapFactory); + // (negative) offset relative to sp + total frame size + initialSpillSize = returnAddressSize(); + spillSize = initialSpillSize; + } + + @Override + public int totalFrameSize() { + return frameSize() + returnAddressSize(); + } + + @Override + public int currentFrameSize() { + return alignFrameSize(outgoingSize + spillSize - returnAddressSize()); + } + + @Override + protected int alignFrameSize(int size) { + return NumUtil.roundUp(size + returnAddressSize(), getTarget().stackAlignment) - returnAddressSize(); + } + + @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)); + } +}