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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * You should have received a copy of the GNU General Public License version

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package org.graalvm.compiler.lir.amd64;

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

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

import static org.graalvm.compiler.core.common.GraalOptions.GeneratePIC;

import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.ILLEGAL;

import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;

import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.STACK;

import static org.graalvm.compiler.lir.LIRValueUtil.differentRegisters;

import org.graalvm.compiler.asm.amd64.AMD64Assembler.ConditionFlag;

import org.graalvm.compiler.asm.amd64.AMD64MacroAssembler;

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

import org.graalvm.compiler.core.common.spi.ForeignCallLinkage;

import org.graalvm.compiler.lir.LIRFrameState;

import org.graalvm.compiler.lir.LIRInstructionClass;

import org.graalvm.compiler.lir.Opcode;

import org.graalvm.compiler.lir.asm.CompilationResultBuilder;

import org.graalvm.compiler.lir.gen.DiagnosticLIRGeneratorTool.ZapRegistersAfterInstruction;

import jdk.vm.ci.amd64.AMD64;

import jdk.vm.ci.amd64.AMD64Kind;

import jdk.vm.ci.code.Register;

import jdk.vm.ci.code.RegisterValue;

import jdk.vm.ci.meta.AllocatableValue;

import jdk.vm.ci.meta.InvokeTarget;

import jdk.vm.ci.meta.ResolvedJavaMethod;

import jdk.vm.ci.meta.Value;

public class AMD64Call {

    public abstract static class CallOp extends AMD64LIRInstruction {

        public static final LIRInstructionClass<CallOp> TYPE = LIRInstructionClass.create(CallOp.class);

        @Def({REG, ILLEGAL}) protected Value result;

        @Use({REG, STACK}) protected Value[] parameters;

        @Temp({REG, STACK}) protected Value[] temps;

        @State protected LIRFrameState state;

        protected CallOp(LIRInstructionClass<? extends CallOp> c, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            super(c);

            this.result = result;

            this.parameters = parameters;

            this.state = state;

            this.temps = addStackSlotsToTemporaries(parameters, temps);

            assert temps != null;

        }

        @Override

        public boolean destroysCallerSavedRegisters() {

            return true;

        }

    }

    public abstract static class MethodCallOp extends CallOp {

        public static final LIRInstructionClass<MethodCallOp> TYPE = LIRInstructionClass.create(MethodCallOp.class);

        protected final ResolvedJavaMethod callTarget;

        protected MethodCallOp(LIRInstructionClass<? extends MethodCallOp> c, ResolvedJavaMethod callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            super(c, result, parameters, temps, state);

            this.callTarget = callTarget;

        }

    }

    @Opcode("CALL_DIRECT")

    public static class DirectCallOp extends MethodCallOp {

        public static final LIRInstructionClass<DirectCallOp> TYPE = LIRInstructionClass.create(DirectCallOp.class);

        public DirectCallOp(ResolvedJavaMethod callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            this(TYPE, callTarget, result, parameters, temps, state);

        }

        protected DirectCallOp(LIRInstructionClass<? extends DirectCallOp> c, ResolvedJavaMethod callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            super(c, callTarget, result, parameters, temps, state);

        }

        @Override

        public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {

            directCall(crb, masm, callTarget, null, true, state);

        }

        public int emitCall(CompilationResultBuilder crb, AMD64MacroAssembler masm) {

            return directCall(crb, masm, callTarget, null, true, state);

        }

    }

    @Opcode("CALL_INDIRECT")

    public static class IndirectCallOp extends MethodCallOp {

        public static final LIRInstructionClass<IndirectCallOp> TYPE = LIRInstructionClass.create(IndirectCallOp.class);

        @Use({REG}) protected Value targetAddress;

        public IndirectCallOp(ResolvedJavaMethod callTarget, Value result, Value[] parameters, Value[] temps, Value targetAddress, LIRFrameState state) {

            this(TYPE, callTarget, result, parameters, temps, targetAddress, state);

        }

        protected IndirectCallOp(LIRInstructionClass<? extends IndirectCallOp> c, ResolvedJavaMethod callTarget, Value result, Value[] parameters, Value[] temps, Value targetAddress,

                        LIRFrameState state) {

            super(c, callTarget, result, parameters, temps, state);

            this.targetAddress = targetAddress;

        }

        @Override

        public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {

            indirectCall(crb, masm, asRegister(targetAddress), callTarget, state);

        }

        @Override

        public void verify() {

            super.verify();

            assert isRegister(targetAddress) : "The current register allocator cannot handle variables to be used at call sites, it must be in a fixed register for now";

        }

    }

    public abstract static class ForeignCallOp extends CallOp implements ZapRegistersAfterInstruction {

        public static final LIRInstructionClass<ForeignCallOp> TYPE = LIRInstructionClass.create(ForeignCallOp.class);

        protected final ForeignCallLinkage callTarget;

        public ForeignCallOp(LIRInstructionClass<? extends ForeignCallOp> c, ForeignCallLinkage callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            super(c, result, parameters, temps, state);

            this.callTarget = callTarget;

        }

        @Override

        public boolean destroysCallerSavedRegisters() {

            return callTarget.destroysRegisters();

        }

    }

    @Opcode("NEAR_FOREIGN_CALL")

    public static final class DirectNearForeignCallOp extends ForeignCallOp {

        public static final LIRInstructionClass<DirectNearForeignCallOp> TYPE = LIRInstructionClass.create(DirectNearForeignCallOp.class);

        public DirectNearForeignCallOp(ForeignCallLinkage linkage, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            super(TYPE, linkage, result, parameters, temps, state);

        }

        @Override

        public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {

            directCall(crb, masm, callTarget, null, false, state);

        }

    }

    @Opcode("FAR_FOREIGN_CALL")

    public static final class DirectFarForeignCallOp extends ForeignCallOp {

        public static final LIRInstructionClass<DirectFarForeignCallOp> TYPE = LIRInstructionClass.create(DirectFarForeignCallOp.class);

        @Temp({REG}) protected AllocatableValue callTemp;

        public DirectFarForeignCallOp(ForeignCallLinkage callTarget, Value result, Value[] parameters, Value[] temps, LIRFrameState state) {

            super(TYPE, callTarget, result, parameters, temps, state);

            /*

             * The register allocator does not support virtual registers that are used at the call

             * site, so use a fixed register.

             */

            callTemp = AMD64.rax.asValue(LIRKind.value(AMD64Kind.QWORD));

            assert differentRegisters(parameters, callTemp);

        }

        @Override

        public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) {

            directCall(crb, masm, callTarget, ((RegisterValue) callTemp).getRegister(), false, state);

        }

    }

    public static int directCall(CompilationResultBuilder crb, AMD64MacroAssembler masm, InvokeTarget callTarget, Register scratch, boolean align, LIRFrameState info) {

        if (align) {

            emitAlignmentForDirectCall(crb, masm);

        }

        int before = masm.position();

        int callPCOffset;

        if (scratch != null && !GeneratePIC.getValue(crb.getOptions())) {

            // offset might not fit a 32-bit immediate, generate an

            // indirect call with a 64-bit immediate

            masm.movq(scratch, 0L);

            callPCOffset = masm.position();

            masm.call(scratch);

        } else {

            callPCOffset = masm.position();

            masm.call();

        }

        int after = masm.position();

        crb.recordDirectCall(before, after, callTarget, info);

        crb.recordExceptionHandlers(after, info);

        masm.ensureUniquePC();

        return callPCOffset;

    }

    protected static void emitAlignmentForDirectCall(CompilationResultBuilder crb, AMD64MacroAssembler masm) {

        // make sure that the displacement word of the call ends up word aligned

        int offset = masm.position();

        offset += crb.target.arch.getMachineCodeCallDisplacementOffset();

        int modulus = crb.target.wordSize;

        if (offset % modulus != 0) {

            masm.nop(modulus - offset % modulus);

        }

    }

    public static int directJmp(CompilationResultBuilder crb, AMD64MacroAssembler masm, InvokeTarget target) {

        return directJmp(crb, masm, target, null);

    }

    public static int directJmp(CompilationResultBuilder crb, AMD64MacroAssembler masm, InvokeTarget target, Register scratch) {

        int before = masm.position();

        int callPCOffset;

        if (scratch != null && !GeneratePIC.getValue(crb.getOptions())) {

            // offset might not fit a 32-bit immediate, generate an

            // indirect call with a 64-bit immediate

            masm.movq(scratch, 0L);

            callPCOffset = masm.position();

            masm.jmp(scratch);

        } else {

            callPCOffset = masm.position();

            masm.jmp(0, true);

        }

        int after = masm.position();

        crb.recordDirectCall(before, after, target, null);

        masm.ensureUniquePC();

        return callPCOffset;

    }

    public static void directConditionalJmp(CompilationResultBuilder crb, AMD64MacroAssembler masm, InvokeTarget target, ConditionFlag cond) {

        int before = masm.position();

        masm.jcc(cond, 0, true);

        int after = masm.position();

        crb.recordDirectCall(before, after, target, null);

        masm.ensureUniquePC();

    }

    public static int indirectCall(CompilationResultBuilder crb, AMD64MacroAssembler masm, Register dst, InvokeTarget callTarget, LIRFrameState info) {

        int before = masm.position();

        masm.call(dst);

        int after = masm.position();

        crb.recordIndirectCall(before, after, callTarget, info);

        crb.recordExceptionHandlers(after, info);

        masm.ensureUniquePC();

        return before;

    }

}