/// <summary>
/// Creates a CIL instruction stream builder.
/// </summary>
/// <param name="selector">
/// The instruction selector to use.
/// </param>
public static CilInstructionStreamBuilder Create(CilInstructionSelector selector)
{
return(new CilInstructionStreamBuilder(selector));
}
/// <summary>
/// Compiles the source body to a CIL method body.
/// </summary>
/// <returns>A CIL method body.</returns>
public Mono.Cecil.Cil.MethodBody Compile()
{
// Create a method body.
var result = new Mono.Cecil.Cil.MethodBody(Method);
// Figure out which 'alloca' values can be replaced
// by local variables. Usually, that's all of them.
var sourceGraph = SourceBody.Implementation;
var allocaToVarMap = AllocasToVariables(sourceGraph);
// Select instructions.
var selector = new CilInstructionSelector(Method, TypeEnvironment, allocaToVarMap);
var streamBuilder = new LinearInstructionStreamBuilder <CilCodegenInstruction>(
selector);
var codegenInsns = streamBuilder.ToInstructionStream(sourceGraph);
codegenInsns = OptimizeRegisterAccesses(codegenInsns);
// Find the set of loaded values so we can allocate registers to them.
var loadedValues = new HashSet <ValueTag>(
codegenInsns
.SelectMany(insn => insn.Traversal)
.OfType <CilLoadRegisterInstruction>()
.Select(insn => insn.Value));
loadedValues.UnionWith(
codegenInsns
.SelectMany(insn => insn.Traversal)
.OfType <CilAddressOfRegisterInstruction>()
.Select(insn => insn.Value));
// Allocate registers to values.
var regAllocator = new CilRegisterAllocator(
loadedValues,
GetPreallocatedRegisters(sourceGraph),
Method.Module);
var regAllocation = regAllocator.Analyze(sourceGraph);
// Synthesize the actual method body.
var processor = result.GetILProcessor();
var emitter = new CodegenEmitter(processor, regAllocation);
emitter.Emit(codegenInsns);
// Add local variables to method body. Put most popular
// locals first to minimize the number of long-form ldloc/stloc
// instructions.
result.InitLocals = true;
foreach (var pair in emitter.RegisterUseCounts.OrderByDescending(pair => pair.Value))
{
result.Variables.Add(pair.Key);
}
foreach (var local in allocaToVarMap.Values)
{
result.Variables.Add(local);
}
foreach (var temp in selector.Temporaries)
{
result.Variables.Add(temp);
}
// Apply peephole optimizations to the generated method body.
CilPeepholeOptimizer.Optimize(result);
// Apply Cecil's macro optimizations to the generated method body.
MethodBodyRocks.Optimize(result);
return(result);
}
/// <summary>
/// Creates a CIL instruction stream builder.
/// </summary>
/// <param name="selector">An instruction selector.</param>
private CilInstructionStreamBuilder(CilInstructionSelector selector)
: base(selector)
{
}
