void ProcessBlock(Block block, ref bool blockContainerNeedsCleanup)
{
bool analysisSuccess = analysis.AnalyzeBlock(block);
if (analysisSuccess && UseCSharpSwitch(out _))
{
// complex multi-block switch that can be combined into a single SwitchInstruction
ILInstruction switchValue = new LdLoc(analysis.SwitchVariable);
Debug.Assert(switchValue.ResultType.IsIntegerType() || switchValue.ResultType == StackType.Unknown);
if (!(switchValue.ResultType == StackType.I4 || switchValue.ResultType == StackType.I8))
{
// switchValue must have a result type of either I4 or I8
switchValue = new Conv(switchValue, PrimitiveType.I8, false, Sign.Signed);
}
var sw = new SwitchInstruction(switchValue);
foreach (var section in analysis.Sections)
{
sw.Sections.Add(new SwitchSection {
Labels = section.Key,
Body = section.Value
});
}
if (block.Instructions.Last() is SwitchInstruction)
{
// we'll replace the switch
}
else
{
Debug.Assert(block.Instructions.SecondToLastOrDefault() is IfInstruction);
// Remove branch/leave after if; it's getting moved into a section.
block.Instructions.RemoveAt(block.Instructions.Count - 1);
}
sw.AddILRange(block.Instructions[block.Instructions.Count - 1]);
block.Instructions[block.Instructions.Count - 1] = sw;
// mark all inner blocks that were converted to the switch statement for deletion
foreach (var innerBlock in analysis.InnerBlocks)
{
Debug.Assert(innerBlock.Parent == block.Parent);
Debug.Assert(innerBlock != ((BlockContainer)block.Parent).EntryPoint);
innerBlock.Instructions.Clear();
}
controlFlowGraph = null; // control flow graph is no-longer valid
blockContainerNeedsCleanup = true;
SortSwitchSections(sw);
}
else
{
// 2nd pass of SimplifySwitchInstruction (after duplicating return blocks),
// (1st pass was in ControlFlowSimplification)
SimplifySwitchInstruction(block, context);
}
}
