/// <summary>
/// Removes the basic block with a particular tag from this
/// control-flow graph.
/// </summary>
/// <param name="tag">The basic block's tag.</param>
/// <returns>
/// A new control-flow graph that does not contain the basic block.
/// </returns>
public FlowGraph RemoveBasicBlock(BasicBlockTag tag)
{
AssertContainsBasicBlock(tag);
var newGraph = new FlowGraph(this, new RemoveBasicBlockUpdate(tag));
var oldData = blocks[tag];
var oldParams = oldData.Parameters;
var oldInsns = oldData.InstructionTags;
var paramTypeBuilder = newGraph.blockParamTypes.ToBuilder();
var valueParentBuilder = newGraph.valueParents.ToBuilder();
int oldParamCount = oldParams.Count;
for (int i = 0; i < oldParamCount; i++)
{
paramTypeBuilder.Remove(oldParams[i].Tag);
valueParentBuilder.Remove(oldParams[i].Tag);
}
valueParentBuilder.RemoveRange(oldInsns);
newGraph.blockParamTypes = paramTypeBuilder.ToImmutable();
newGraph.valueParents = valueParentBuilder.ToImmutable();
newGraph.instructions = newGraph.instructions.RemoveRange(oldInsns);
newGraph.blocks = newGraph.blocks.Remove(tag);
return(newGraph);
}
internal BasicBlock(FlowGraph graph, BasicBlockTag tag, BasicBlockData data)
{
this = default(BasicBlock);
this.Graph = graph;
this.Tag = tag;
this.data = data;
}
internal NamedInstruction InsertInstructionInBasicBlock(
BasicBlockTag blockTag,
Instruction instruction,
ValueTag insnTag,
int index)
{
AssertContainsBasicBlock(blockTag);
AssertNotContainsValue(insnTag);
var oldBlockData = blocks[blockTag];
var newBlockData = new BasicBlockData(
oldBlockData.Parameters,
oldBlockData.InstructionTags.Insert(index, insnTag),
oldBlockData.Flow);
var newGraph = new FlowGraph(this, new AddInstructionUpdate(insnTag, instruction));
newGraph.blocks = newGraph.blocks.SetItem(blockTag, newBlockData);
newGraph.instructions = newGraph.instructions.Add(insnTag, instruction);
newGraph.valueParents = newGraph.valueParents.Add(insnTag, blockTag);
return(new NamedInstruction(
new BasicBlock(newGraph, blockTag, newBlockData),
insnTag,
instruction,
index));
}
/// <summary>
/// Moves this instruction from its current location to a
/// the end of a basic block.
/// </summary>
/// <param name="block">
/// The block to move this instruction to.
/// </param>
public void MoveTo(BasicBlockTag block)
{
var data = this.Instruction;
var target = Graph.GetBasicBlock(block);
Graph.RemoveInstruction(Tag);
target.AppendInstruction(data, Tag);
}
/// <summary>
/// Creates a new control-flow graph that takes the basic block
/// with a particular tag as entry point.
/// </summary>
/// <param name="tag">The tag of the new entry point block.</param>
/// <returns>A control-flow graph.</returns>
public FlowGraph WithEntryPoint(BasicBlockTag tag)
{
AssertContainsBasicBlock(tag);
var newGraph = new FlowGraph(this, new SetEntryPointUpdate(tag));
newGraph.EntryPointTag = tag;
return(newGraph);
}
/// <summary>
/// Moves this instruction from its current location to a
/// particular position in a block.
/// </summary>
/// <param name="index">
/// The position in <paramref name="block"/> at which to insert
/// this instruction.
/// </param>
/// <param name="block">
/// The block to move this instruction to.
/// </param>
public void MoveTo(int index, BasicBlockTag block)
{
var data = this.Instruction;
var target = Graph.GetBasicBlock(block);
Graph.RemoveInstruction(Tag);
target.InsertInstruction(index, data, Tag);
}
/// <summary>
/// Creates a new basic block that includes all basic blocks in this
/// graph plus an empty basic block. The latter basic block is returned.
/// </summary>
/// <param name="name">The (preferred) name of the basic block's tag.</param>
/// <returns>An empty basic block in a new control-flow graph.</returns>
public BasicBlock AddBasicBlock(string name)
{
var tag = new BasicBlockTag(name);
var data = new BasicBlockData();
var newGraph = new FlowGraph(this, new AddBasicBlockUpdate(tag));
newGraph.blocks = newGraph.blocks.Add(tag, data);
return(new BasicBlock(newGraph, tag, data));
}
internal BasicBlock UpdateBasicBlockParameters(
BasicBlockTag tag,
ImmutableList <BlockParameter> parameters)
{
AssertContainsBasicBlock(tag);
var oldBlock = blocks[tag];
var newData = new BasicBlockData(
parameters,
oldBlock.InstructionTags,
oldBlock.Flow);
var oldData = blocks[tag];
var oldParams = oldData.Parameters;
var newGraph = new FlowGraph(this, new BasicBlockParametersUpdate(tag));
var paramTypeBuilder = newGraph.blockParamTypes.ToBuilder();
var valueParentBuilder = newGraph.valueParents.ToBuilder();
// Remove the basic block's parameters from the value parent
// and parameter type dictionaries.
int oldParamCount = oldParams.Count;
for (int i = 0; i < oldParamCount; i++)
{
paramTypeBuilder.Remove(oldParams[i].Tag);
valueParentBuilder.Remove(oldParams[i].Tag);
}
// Add the new basic block parameters to the value parent and
// parameter type dictionaries.
int newParamCount = parameters.Count;
for (int i = 0; i < newParamCount; i++)
{
var item = parameters[i];
ContractHelpers.Assert(
!valueParentBuilder.ContainsKey(item.Tag),
"Value tag '" + item.Tag.Name + "' cannot appear twice in the same control-flow graph.");
paramTypeBuilder.Add(item.Tag, item.Type);
valueParentBuilder.Add(item.Tag, tag);
}
newGraph.blockParamTypes = paramTypeBuilder.ToImmutable();
newGraph.valueParents = valueParentBuilder.ToImmutable();
newGraph.blocks = newGraph.blocks.SetItem(tag, newData);
return(new BasicBlock(newGraph, tag, newData));
}
internal BasicBlock UpdateBasicBlockFlow(BasicBlockTag tag, BlockFlow flow)
{
AssertContainsBasicBlock(tag);
var oldBlock = blocks[tag];
var newData = new BasicBlockData(
oldBlock.Parameters,
oldBlock.InstructionTags,
flow);
var newGraph = new FlowGraph(this, new BasicBlockFlowUpdate(tag));
newGraph.blocks = newGraph.blocks.SetItem(tag, newData);
return(new BasicBlock(newGraph, tag, newData));
}
/// <summary>
/// Creates a basic block builder from a graph and a tag.
/// </summary>
/// <param name="graph">The basic block builder's defining graph.</param>
/// <param name="tag">The basic block's tag.</param>
internal BasicBlockBuilder(FlowGraphBuilder graph, BasicBlockTag tag)
{
this.Graph = graph;
this.Tag = tag;
}
/// <summary>
/// Checks if this control-flow graph contains a basic block
/// with a particular tag.
/// </summary>
/// <param name="tag">The basic block's tag.</param>
/// <returns>
/// <c>true</c> if this control-flow graph contains a basic block
/// with the given tag; otherwise, <c>false</c>.
/// </returns>
public bool ContainsBasicBlock(BasicBlockTag tag)
{
return(ImmutableGraph.ContainsBasicBlock(tag));
}
/// <summary>
/// Gets the basic block with a particular tag.
/// </summary>
/// <param name="tag">The basic block's tag.</param>
/// <returns>A basic block.</returns>
public BasicBlockBuilder GetBasicBlock(BasicBlockTag tag)
{
return(new BasicBlockBuilder(this, tag));
}
/// <summary>
/// Removes the basic block with a particular tag from this
/// control-flow graph.
/// </summary>
/// <param name="tag">The basic block's tag.</param>
public void RemoveBasicBlock(BasicBlockTag tag)
{
ImmutableGraph = ImmutableGraph.RemoveBasicBlock(tag);
}
/// <summary>
/// Replaces this branch's target with another block.
/// </summary>
/// <param name="target">The new target block.</param>
/// <returns>A new branch.</returns>
public Branch WithTarget(BasicBlockTag target)
{
return(new Branch(target, Arguments));
}
/// <summary>
/// Creates a branch that targets a particular block and
/// passes a list of arguments.
/// </summary>
/// <param name="target">The target block.</param>
/// <param name="arguments">
/// A list of arguments to pass to the target block.
/// </param>
public Branch(BasicBlockTag target, IReadOnlyList <BranchArgument> arguments)
{
this.Target = target;
this.Arguments = arguments;
}
/// <summary>
/// Creates a branch that targets a particular block and
/// passes a list of arguments.
/// </summary>
/// <param name="target">The target block.</param>
/// <param name="arguments">
/// A list of arguments to pass to the target block.
/// </param>
public Branch(BasicBlockTag target, IReadOnlyList <ValueTag> arguments)
: this(target, arguments.EagerSelect(BranchArgument.FromValue))
{
}
/// <summary>
/// Creates a branch that targets a particular block and
/// passes no arguments.
/// </summary>
/// <param name="target">The target block.</param>
public Branch(BasicBlockTag target)
: this(target, EmptyArray <BranchArgument> .Value)
{
}
/// <summary>
/// Gets the basic block with a particular tag.
/// </summary>
/// <param name="tag">The basic block's tag.</param>
/// <returns>A basic block.</returns>
public BasicBlock GetBasicBlock(BasicBlockTag tag)
{
AssertContainsBasicBlock(tag);
return(new BasicBlock(this, tag, blocks[tag]));
}
/// <summary>
/// Checks if this control-flow graph contains a basic block
/// with a particular tag.
/// </summary>
/// <param name="tag">The basic block's tag.</param>
/// <returns>
/// <c>true</c> if this control-flow graph contains a basic block
/// with the given tag; otherwise, <c>false</c>.
/// </returns>
public bool ContainsBasicBlock(BasicBlockTag tag)
{
return(blocks.ContainsKey(tag));
}
/// <summary>
/// Asserts that this control-flow graph must contain a basic block
/// with a particular tag.
/// </summary>
/// <param name="tag">
/// The tag of the basic block that must be in the graph.
/// </param>
/// <param name="message">
/// The error message for when no basic block in this control-flow graph
/// has the tag.
/// </param>
public void AssertContainsBasicBlock(BasicBlockTag tag, string message)
{
ContractHelpers.Assert(ContainsBasicBlock(tag), message);
}
/// <summary>
/// Asserts that this control-flow graph must contain a basic block
/// with a particular tag.
/// </summary>
/// <param name="tag">
/// The tag of the basic block that must be in the graph.
/// </param>
public void AssertContainsBasicBlock(BasicBlockTag tag)
{
AssertContainsBasicBlock(tag, "The graph does not contain the given basic block.");
}