public override void ExceptionHandlerSetup(PlaceholderRef site)
{
inExceptHandler++;
region.Write(new byte[] {
0x31, 0xc9, // xor ecx, ecx
0x51 // push ecx
});
region.Write(new byte[] { 0x68 }); // push imm32
region.WritePlaceholderRef(site);
region.Write(new byte[] {
0x51, // push ecx
0xff, 0x75, 0x00, // push [ebp]
0x89, 0x65, 0x00 // mov [ebp], esp
});
}
public override void ExceptionHandlerSetup(PlaceholderRef site)
{
region.Write(new byte[] {
0x48, 0x31, 0xc9, // xor rcx, rcx
0x51 // push rcx
});
region.Write(new byte[] { 0x48, 0xb9 }); // mov rcx, imm64
region.WritePlaceholderRef(site);
region.Write(new byte[] {
0x51, // push rcx
0x48, 0x31, 0xc9, // xor rcx, rcx
0x51, // push rcx
0xff, 0x75, 0x00, // push [rbp]
0x48, 0x89, 0x65, 0x00 // mov [rbp], rsp
});
}
public override void Generate(Generator generator, TypeReference returnType)
{
base.Generate(generator, returnType);
//
generator.Symbols.Source(generator.Assembler.Region.CurrentLocation, this);
PlaceholderRef fonCatchJump = null;
if (finallyStatement != null)
{
fonCatchJump = new PlaceholderRef();
generator.Assembler.ExceptionHandlerSetup(fonCatchJump);
generator.Resolver.EnterContext();
generator.Resolver.RegisterTryContext();
}
PlaceholderRef onCatchJump = null;
if (catches.Count > 0)
{
onCatchJump = new PlaceholderRef();
generator.Assembler.ExceptionHandlerSetup(onCatchJump);
}
generator.Resolver.EnterContext();
generator.Resolver.RegisterTryContext();
statement.Generate(generator, returnType);
returns = statement.Returns();
Resolver.Context statementContext = generator.Resolver.LeaveContextAcquire();
if (catches.Count > 0)
{
generator.Assembler.ExceptionHandlerRemove();
JumpToken noExceptionJump = generator.Assembler.CreateJumpToken();
generator.Assembler.Jump(noExceptionJump);
generator.Assembler.SetDestination(onCatchJump);
JumpToken noReturnJump = generator.Assembler.CreateJumpToken();
generator.Assembler.JumpIfNotMarked(noReturnJump);
generator.Assembler.UnmarkType();
ReturnStatement.DoReturn(this, generator);
generator.Assembler.SetDestination(noReturnJump);
generator.Assembler.StoreVariable(valueSlot);
List <JumpToken> escape = new List <JumpToken>();
foreach (Catch c in catches)
{
generator.Symbols.Source(generator.Assembler.Region.CurrentLocation, c);
generator.Assembler.RetrieveVariable(valueSlot);
JumpToken noMatch = generator.Assembler.CreateJumpToken();
generator.Assembler.TypeConversionDynamicNotNull(c.type.Id);
generator.Assembler.JumpIfUnassigned(noMatch);
generator.Assembler.StoreVariable(valueSlot);
generator.Resolver.EnterContext();
generator.Resolver.AddVariable(c.identifier, c.type, valueSlot, true);
generator.Resolver.AssignSlot(valueSlot);
c.statement.Generate(generator, returnType);
returns = returns && c.statement.Returns();
generator.Resolver.LeaveContext();
JumpToken jt = generator.Assembler.CreateJumpToken();
escape.Add(jt);
generator.Assembler.Jump(jt);
generator.Assembler.SetDestination(noMatch);
}
//unhandled, rethrow
generator.Assembler.RetrieveVariable(valueSlot);
generator.Assembler.ExceptionHandlerInvoke();
foreach (JumpToken jt in escape)
{
generator.Assembler.SetDestination(jt);
}
generator.Assembler.SetDestination(noExceptionJump);
}
if (finallyStatement != null)
{
generator.Symbols.Source(generator.Assembler.Region.CurrentLocation, finallyLocation);
generator.Resolver.LeaveContext();
generator.Assembler.ExceptionHandlerRemove();
generator.Assembler.Empty();
generator.Assembler.SetDestination(fonCatchJump);
JumpToken fnoReturnJump = generator.Assembler.CreateJumpToken();
generator.Assembler.JumpIfNotMarked(fnoReturnJump);
generator.Assembler.UnmarkType();
generator.Assembler.StoreVariable(returnSlot);
generator.Assembler.SetDestination(fnoReturnJump);
generator.Assembler.StoreVariable(valueSlot);
generator.Resolver.EnterContext();
finallyStatement.Generate(generator, returnType);
generator.Resolver.LeaveAndMergeContext();
if (catches.Count == 0) // if there are no catches we can be sure the whole try part completed and so we can use the variables initialized by it.
{
generator.Resolver.MergeContext(statementContext);
}
generator.Assembler.RetrieveVariable(returnSlot);
JumpToken fonExceptionFinallyJump = generator.Assembler.CreateJumpToken();
generator.Assembler.JumpIfUnassigned(fonExceptionFinallyJump);
ReturnStatement.DoReturn(this, generator);
generator.Assembler.SetDestination(fonExceptionFinallyJump);
generator.Assembler.RetrieveVariable(valueSlot);
JumpToken fnoException = generator.Assembler.CreateJumpToken();
generator.Assembler.JumpIfUnassigned(fnoException);
generator.Assembler.ExceptionHandlerInvoke();
generator.Assembler.SetDestination(fnoException);
}
generator.Resolver.ReleaseContext(statementContext);
}