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package org.graalvm.compiler.lir.phases;

import org.graalvm.compiler.lir.LIR;
import org.graalvm.compiler.lir.Variable;
import org.graalvm.compiler.lir.VirtualStackSlot;
import org.graalvm.compiler.lir.gen.LIRGenerationResult;
import org.graalvm.compiler.lir.gen.LIRGeneratorTool;
import org.graalvm.compiler.lir.phases.AllocationPhase.AllocationContext;
import org.graalvm.compiler.lir.phases.PostAllocationOptimizationPhase.PostAllocationOptimizationContext;
import org.graalvm.compiler.lir.phases.PreAllocationOptimizationPhase.PreAllocationOptimizationContext;

import jdk.vm.ci.code.StackSlot;

public class LIRSuites {

    private final LIRPhaseSuite<PreAllocationOptimizationContext> preAllocOptStage;
    private final LIRPhaseSuite<AllocationContext> allocStage;
    private final LIRPhaseSuite<PostAllocationOptimizationContext> postAllocStage;
    private boolean immutable;

    public LIRSuites(LIRPhaseSuite<PreAllocationOptimizationContext> preAllocOptStage, LIRPhaseSuite<AllocationContext> allocStage, LIRPhaseSuite<PostAllocationOptimizationContext> postAllocStage) {
        this.preAllocOptStage = preAllocOptStage;
        this.allocStage = allocStage;
        this.postAllocStage = postAllocStage;
    }

    public LIRSuites(LIRSuites other) {
        this(other.getPreAllocationOptimizationStage().copy(), other.getAllocationStage().copy(), other.getPostAllocationOptimizationStage().copy());
    }

    
PreAllocationOptimizationPhases are executed between LIR generation and register allocation. 
 Implementers can create new variables, stack
slots and virtual stack slots. /**
     * {@link PreAllocationOptimizationPhase}s are executed between {@link LIR} generation and
     * register allocation.
     * <p>
     * {@link PreAllocationOptimizationPhase Implementers} can create new
     * {@link LIRGeneratorTool#newVariable variables}, {@link LIRGenerationResult#getFrameMap stack
     * slots} and {@link LIRGenerationResult#getFrameMapBuilder virtual stack slots}.
     */
    public LIRPhaseSuite<PreAllocationOptimizationContext> getPreAllocationOptimizationStage() {
        return preAllocOptStage;
    }

    
AllocationPhases are responsible for register allocation and translating VirtualStackSlots into StackSlots. 
 After the AllocationStage there should be no more Variables and VirtualStackSlots. /**
     * {@link AllocationPhase}s are responsible for register allocation and translating
     * {@link VirtualStackSlot}s into {@link StackSlot}s.
     * <p>
     * After the {@link AllocationStage} there should be no more {@link Variable}s and
     * {@link VirtualStackSlot}s.
     */
    public LIRPhaseSuite<AllocationContext> getAllocationStage() {
        return allocStage;
    }

    
PostAllocationOptimizationPhases are executed after register allocation and before machine code generation. 
 A PostAllocationOptimizationPhase must not introduce new Variables, VirtualStackSlots or StackSlots. Blocks might be removed from LIR.codeEmittingOrder() by overwriting them with null. /**
     * {@link PostAllocationOptimizationPhase}s are executed after register allocation and before
     * machine code generation.
     * <p>
     * A {@link PostAllocationOptimizationPhase} must not introduce new {@link Variable}s,
     * {@link VirtualStackSlot}s or {@link StackSlot}s. Blocks might be removed from
     * {@link LIR#codeEmittingOrder()} by overwriting them with {@code null}.
     */
    public LIRPhaseSuite<PostAllocationOptimizationContext> getPostAllocationOptimizationStage() {
        return postAllocStage;
    }

    public boolean isImmutable() {
        return immutable;
    }

    public synchronized void setImmutable() {
        if (!immutable) {
            preAllocOptStage.setImmutable();
            allocStage.setImmutable();
            postAllocStage.setImmutable();
            immutable = true;
        }
    }

    public LIRSuites copy() {
        return new LIRSuites(preAllocOptStage.copy(), allocStage.copy(), postAllocStage.copy());
    }
}