public EmitSyntax StackLoop(EmitSyntax emit, Action <EmitSyntax, Def <Locals> > emitLoopBody)
{
var labels = emit.Labels;
var START = labels.Generate();
var END = labels.Generate();
var item = emit.Locals.Generate();
emit
.Local(item, itemType)
.Label(START)
.Ldloc(index.GetRef())
.Ldc_I4(0)
.Beq(END.GetRef())
.Do(Pop)
.Stloc(item.GetRef())
;
emitLoopBody(emit, item);
emit
.Br(START.GetRef())
.Label(END)
.Nop();
return(emit);
}
private void GenerateCodeOrJump(Decision decision)
{
if (!strategy.TryInlineCode(decision))
{
emit.Br(GetNodeLabel(decision));
}
}
public EmitSyntax EmitLoopPass(EmitSyntax emit, bool loop)
{
emit.Label(START);
FetchNext(emit, END);
body(emit);
if (loop)
{
emit.Br(START.GetRef());
}
return(emit
.Label(END)
.Nop());
}
public ILNfaCompiler(AstNode node, EmitSyntax emit, ILCompilerSettings settings)
{
this.Scanner = new StemScanner();
this.emit = emit;
this.settings = settings;
var labels = emit.Labels;
NEXT_THREAD = labels.Generate();
RESUME_ALL = labels.Generate();
NEXT_INPUT = labels.Generate();
THREAD_SUSPEND = labels.Generate();
THREAD_DISPATCH = labels.Generate();
var LABEL0 = labels.Generate();
var LABEL1 = labels.Generate();
var POSTCOMPILEINIT = labels.Generate();
var POSTCOMPILEINIT_BACK = labels.Generate();
var locals = emit.Locals;
slots = locals.Generate();
labelIndexToLocation = locals.Generate();
intTmp = locals.Generate();
threadTmp = locals.Generate();
INfaVM code = this;
this.inputPump = new ArrayLoopGenerator(
valueType: emit.Types.Int32,
ldarray: settings.LdInput,
body:
il => il
.Do(matchedStack.Clear)
.Br(RESUME_ALL.GetRef())
);
this.runningStack = new StackGenerator(emit, typeof(Thread));
this.suspendedStack = new StackGenerator(emit, typeof(Thread));
this.matchedStack = new StackGenerator(emit, typeof(Thread));
this.tmpStack = new StackGenerator(emit, typeof(Thread), nullContainer: true);
emit
.Local(intTmp, emit.Types.Int32)
.Local(slots, emit.Types.Import(typeof(int[])))
.Local(labelIndexToLocation, emit.Types.Import(typeof(int[])))
.Br(POSTCOMPILEINIT.GetRef())
.Label(POSTCOMPILEINIT_BACK)
.Local(threadTmp, emit.Types.Import(typeof(Thread)))
.Ldloca(threadTmp.GetRef())
.Initobj(emit.Types.Import(typeof(Thread)))
.Do(inputPump.EmitInitialization)
;
new RegularNfaVMCompiler().Compile(node, code);
int LabelCount = Math.Max(1, indexToLabel.Count);
this.runningStack.SetSize(LabelCount);
this.suspendedStack.SetSize(LabelCount);
this.matchedStack.SetSize(LabelCount);
this.tmpStack.SetSize(LabelCount);
emit
.Label(POSTCOMPILEINIT)
.Do(runningStack.Init)
.Do(suspendedStack.Init)
.Do(matchedStack.Init)
.Do(tmpStack.Init)
.Ldc_I4(slotCount)
.Newarr(emit.Types.Int32)
.Stloc(slots.GetRef())
.Ldc_I4(LabelCount)
.Newarr(emit.Types.Int32)
.Stloc(labelIndexToLocation.GetRef())
// Fill labelIndexToLocation with -1 :
.Ldc_I4(LabelCount).Stloc(intTmp.GetRef())
.Label(LABEL1)
.Ldloc(intTmp.GetRef())
.Ldc_I4_0()
.Beq(LABEL0.GetRef())
.Ldloc(intTmp.GetRef())
.Ldc_I4(1)
.Sub()
.Stloc(intTmp.GetRef())
.Ldloc(labelIndexToLocation.GetRef())
.Ldloc(intTmp.GetRef())
.Ldc_I4(int.MinValue)
.Stelem_I4()
.Br(LABEL1.GetRef())
.Label(LABEL0)
.Br(POSTCOMPILEINIT_BACK.GetRef());
// Save thread as suspended (stack should already contain label index to suspend)
emit.Label(THREAD_SUSPEND);
StThreadValueByRuntimeLabelIndex();
emit
// Don't add thread if same thread (same label index
// with current input location) already exists in a list.
.Ldloc(labelIndexToLocation.GetRef())
.Ldloca(threadTmp.GetRef())
.Ldfld(LabelIndexField)
.Ldelem_I4()
.Ldloc(inputPump.Index.GetRef())
.Beq(NEXT_THREAD.GetRef())
// Mark label index as visited
.Ldloc(labelIndexToLocation.GetRef())
.Ldloca(threadTmp.GetRef())
.Ldfld(LabelIndexField)
.Ldloc(inputPump.Index.GetRef())
.Stelem_I4()
;
suspendedStack.PushFrom(emit, threadTmp);
emit
.Br(NEXT_THREAD.GetRef())
.Label(RESUME_ALL)
.Swap(suspendedStack.Stack, runningStack.Stack, tmpStack.Stack)
.Swap(suspendedStack.Index, runningStack.Index, tmpStack.Index)
.Label(NEXT_THREAD)
;
runningStack
.StackLoop(
emit,
(emit2, thread) =>
{
emit2
.Ldloca(thread.GetRef())
.Ldfld(LabelIndexField)
.Label(THREAD_DISPATCH)
.Switch(indexToLabel.Select(def => def.GetRef()).ToArray())
.Br(settings.FAILURE.GetRef());
})
;
emit
.Br(NEXT_INPUT.GetRef())
;
emit
.Label(NEXT_INPUT)
;
inputPump.EmitLoopPass(emit, false);
emit
// Check if there are matched threads:
.Do(matchedStack.LdCount)
.Ldc_I4_0()
.Beq(settings.FAILURE.GetRef())
.Br(settings.SUCCESS.GetRef());
}
public void Build(EmitSyntax emit)
{
// Debug.WriteLine("DFA for " + descriptor.Name + ":");
// Debug.WriteLine(dfa);
int failState = dfa.StateCount;
var locals = emit.Locals;
var labels = emit.Labels;
var FIN = labels.Generate();
var current = locals.Generate("ch");
var Lgoto = new Ref <Labels> [dfa.StateCount + 1]; // label for incrementing ch position
var Mgoto = new Ref <Labels> [dfa.StateCount]; // assing ch using current position
var Tgoto = new Ref <Labels> [dfa.StateCount]; // transition dispatching switch-code
for (int i = 0; i != dfa.StateCount; ++i)
{
Lgoto[i] = labels.Generate().GetRef();
Mgoto[i] = labels.Generate().GetRef();
Tgoto[i] = labels.Generate().GetRef();
}
Lgoto[failState] = FIN.GetRef();
emit
.Local(current, emit.Types.Char)
.Ldarg(0).Ldfld((ScanCursor c) => c.InnerState)
.Switch(Mgoto)
.Br(Lgoto[0])
;
foreach (var S in dfa.EnumerateStates())
{
int state = S.Index;
emit
.Label(Lgoto[state].Def);
if (state != dfa.Start)
{
// ++Cursor
emit
.Ldarg(0) // for Stfld
.Ldarg(0).Ldfld((ScanCursor c) => c.Cursor)
.Ldc_I4_1()
.Add()
.Stfld((ScanCursor c) => c.Cursor)
;
}
// If state is accepring then remember position
// in Marker and save corresponding ActionId.
if (S.IsAccepting)
{
int actionCount = 0;
foreach (var action in S.Actions)
{
emit
.Ldarg(0)
.Ldfld((ScanCursor c) => c.Actions)
.Ldc_I4(actionCount++)
.Ldc_I4(action)
.Stelem_I4()
;
}
emit
.Ldarg(0)
.Ldc_I4(actionCount)
.Stfld((ScanCursor c) => c.ActionCount)
;
emit
.Ldarg(0)
.Ldc_I4(S.EnvelopeId)
.Stfld((ScanCursor c) => c.EnvelopeId)
;
emit
.Ldarg(0)
.Ldarg(0).Ldfld((ScanCursor c) => c.Cursor)
.Stfld((ScanCursor c) => c.Marker);
// Save line/column information
emit
// cursor.MarkerLine = cursor.CursorLine;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.CursorLine)
.Stfld((ScanCursor c) => c.MarkerLine)
// cursor.MarkerLineStart = cursor.CursorLineStart;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.CursorLineStart)
.Stfld((ScanCursor c) => c.MarkerLineStart)
;
}
if (S.IsNewline)
{
emit
// ++cursor.CursorLine;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.CursorLine)
.Ldc_I4_1()
.Add()
.Stfld((ScanCursor c) => c.CursorLine)
// cursor.CursorLineStart = cursor.Cursor;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.Cursor)
.Stfld((ScanCursor c) => c.CursorLineStart)
;
}
emit
.Label(Mgoto[state].Def)
// Get current input symbol
.Ldarg(0).Ldfld((ScanCursor c) => c.Buffer)
.Ldarg(0).Ldfld((ScanCursor c) => c.Cursor)
.Ldelem_U2()
.Stloc(current.GetRef())
// Label for tunneling
.Label(Tgoto[state].Def)
;
if (S.IsFinal && state != 0)
{
emit
.Br(FIN.GetRef());
continue;
}
int checkSentinelState = failState + 1;
var stateRealTransitions = dfa.EnumerateRealTransitions(S).ToList();
// Find custom sentinel transtion
int customSentinelToState = -1;
var customSentinelTransitionIndex =
stateRealTransitions.FindIndex(pair => pair.Key.Contains(Sentinel));
if (customSentinelTransitionIndex >= 0)
{
customSentinelToState = stateRealTransitions[customSentinelTransitionIndex].Value;
}
// Sentinel check transiiton
var sentinelTransition = new IntArrow <int>(Sentinel, checkSentinelState);
stateRealTransitions.Insert(0, sentinelTransition);
var generator = SwitchGenerator.Sparse(
stateRealTransitions.ToArray(),
failState,
UnicodeIntSetType.UnicodeInterval,
frequency: UnicodeFrequency.Default);
generator.Build(
emit,
il => il.Ldloc(current.GetRef()),
(EmitSyntax il, int value) =>
{
if (value == checkSentinelState)
{
var handleSentinelCharLabel =
(customSentinelToState >= 0)
? Lgoto[customSentinelToState]
: FIN.GetRef();
// return for buffer filling if Cursor == Limit,
// otherwise transite on char
il
.Ldarg(0).Ldfld((ScanCursor c) => c.Limit)
.Ldarg(0).Ldfld((ScanCursor c) => c.Cursor)
.Bne_Un(handleSentinelCharLabel)
// Return for buffer filling
.Ldarg(0)
.Ldc_I4(state)
.Stfld((ScanCursor c) => c.InnerState)
.Ldc_I4(1)
.Ret()
;
}
else if (value == failState && S.Tunnel >= 0)
{
// Tunnel-jump to other state and verify current
// input again in that state.
il.Br(Tgoto[S.Tunnel]);
}
else
{
// Transite to the valid or failed state
il.Br(Lgoto[value]);
}
});
}
// Return to the last accepted position and report accept stage
emit
.Label(FIN)
.Ldc_I4(0)
.Ret()
;
}
public void BuildBody(
EmitSyntax emit,
LanguageData data,
Ref <Args> ruleId,
Ref <Args> ruleArgs,
Ref <Args> argsStart,
Ref <Args> ctx,
Ref <Args> lookbackStart)
{
Def <Labels> returnLabel = emit.Labels.Generate();
var contextCode = new ContextCode(
emit,
il => il.Ldarg(ctx),
il => il.Ldarg(lookbackStart),
data,
data.Grammar.GlobalContextProvider,
data.LocalParseContexts);
IActionCode code = new ProductionCode(
emit,
contextCode,
ldRuleArgs: il => il.Ldarg(ruleArgs),
ldArgsStart: il => il.Ldarg(argsStart),
returnLabel: returnLabel);
var defaultLabel = emit.Labels.Generate();
var endWithSingleResultLabel = emit.Labels.Generate();
var jumpTable = new Ref <Labels> [data.Grammar.Productions.Count];
for (int i = 0; i != jumpTable.Length; ++i)
{
jumpTable[i] = emit.Labels.Generate().GetRef();
}
emit
.Do(il => il.Ldarg(ruleId))
.Switch(jumpTable)
.Br(defaultLabel.GetRef());
foreach (var prod in data.Grammar.Productions)
{
emit.Label(jumpTable[prod.Index].Def);
if (0 == prod.Actions.Count)
{
// Augumented start rule has null action and should never be invoked.
// Also it is possible that for some platforms production may have default
// action.
emit.Ldnull();
}
else
{
foreach (var action in prod.Actions)
{
code = GenerateActionCode(code, action);
}
}
emit.Br(endWithSingleResultLabel.GetRef());
}
emit
.Label(defaultLabel)
.Ldnull()
.Label(endWithSingleResultLabel)
.Label(returnLabel)
.Ret();
}
public EmitSyntax EmitLoopPass(EmitSyntax emit, bool loop)
{
emit.Label(START);
FetchNext(emit, END);
body(emit);
if (loop)
{
emit.Br(START.GetRef());
}
return emit
.Label(END)
.Nop();
}
public void BuildBody(
EmitSyntax emit,
LanguageData data,
Ref<Args> ruleId,
Ref<Args> ruleArgs,
Ref<Args> argsStart,
Ref<Args> ctx,
Ref<Args> lookbackStart)
{
Def<Labels> returnLabel = emit.Labels.Generate();
var contextCode = new ContextCode(
emit,
il => il.Ldarg(ctx),
il => il.Ldarg(lookbackStart),
data,
data.Grammar.GlobalContextProvider,
data.LocalParseContexts);
IActionCode code = new ProductionCode(
emit,
contextCode,
ldRuleArgs: il => il.Ldarg(ruleArgs),
ldArgsStart: il => il.Ldarg(argsStart),
returnLabel: returnLabel);
var defaultLabel = emit.Labels.Generate();
var endWithSingleResultLabel = emit.Labels.Generate();
var jumpTable = new Ref<Labels>[data.Grammar.Productions.Count];
for (int i = 0; i != jumpTable.Length; ++i)
{
jumpTable[i] = emit.Labels.Generate().GetRef();
}
emit
.Do(il => il.Ldarg(ruleId))
.Switch(jumpTable)
.Br(defaultLabel.GetRef());
foreach (var prod in data.Grammar.Productions)
{
emit.Label(jumpTable[prod.Index].Def);
if (0 == prod.Actions.Count)
{
// Augumented start rule has null action and should never be invoked.
// Also it is possible that for some platforms production may have default
// action.
emit.Ldnull();
}
else
{
foreach (var action in prod.Actions)
{
code = GenerateActionCode(code, action);
}
}
emit.Br(endWithSingleResultLabel.GetRef());
}
emit
.Label(defaultLabel)
.Ldnull()
.Label(endWithSingleResultLabel)
.Label(returnLabel)
.Ret();
}
public IActionCode ReturnFromAction()
{
emit.Br(RETURN);
return(this);
}
public void EmitReturn()
{
emit.Br(ReturnLabel.GetRef());
}
public ILNfaCompiler(AstNode node, EmitSyntax emit, ILCompilerSettings settings)
{
this.Scanner = new StemScanner();
this.emit = emit;
this.settings = settings;
var labels = emit.Labels;
NEXT_THREAD = labels.Generate();
RESUME_ALL = labels.Generate();
NEXT_INPUT = labels.Generate();
THREAD_SUSPEND = labels.Generate();
THREAD_DISPATCH = labels.Generate();
var LABEL0 = labels.Generate();
var LABEL1 = labels.Generate();
var POSTCOMPILEINIT = labels.Generate();
var POSTCOMPILEINIT_BACK = labels.Generate();
var locals = emit.Locals;
slots = locals.Generate();
labelIndexToLocation = locals.Generate();
intTmp = locals.Generate();
threadTmp = locals.Generate();
INfaVM code = this;
this.inputPump = new ArrayLoopGenerator(
valueType: emit.Types.Int32,
ldarray: settings.LdInput,
body:
il => il
.Do(matchedStack.Clear)
.Br(RESUME_ALL.GetRef())
);
this.runningStack = new StackGenerator(emit, typeof(Thread));
this.suspendedStack = new StackGenerator(emit, typeof(Thread));
this.matchedStack = new StackGenerator(emit, typeof(Thread));
this.tmpStack = new StackGenerator(emit, typeof(Thread), nullContainer: true);
emit
.Local(intTmp, emit.Types.Int32)
.Local(slots, emit.Types.Import(typeof(int[])))
.Local(labelIndexToLocation, emit.Types.Import(typeof(int[])))
.Br(POSTCOMPILEINIT.GetRef())
.Label(POSTCOMPILEINIT_BACK)
.Local(threadTmp, emit.Types.Import(typeof(Thread)))
.Ldloca(threadTmp.GetRef())
.Initobj(emit.Types.Import(typeof(Thread)))
.Do(inputPump.EmitInitialization)
;
new RegularNfaVMCompiler().Compile(node, code);
int LabelCount = Math.Max(1, indexToLabel.Count);
this.runningStack.SetSize(LabelCount);
this.suspendedStack.SetSize(LabelCount);
this.matchedStack.SetSize(LabelCount);
this.tmpStack.SetSize(LabelCount);
emit
.Label(POSTCOMPILEINIT)
.Do(runningStack.Init)
.Do(suspendedStack.Init)
.Do(matchedStack.Init)
.Do(tmpStack.Init)
.Ldc_I4(slotCount)
.Newarr(emit.Types.Int32)
.Stloc(slots.GetRef())
.Ldc_I4(LabelCount)
.Newarr(emit.Types.Int32)
.Stloc(labelIndexToLocation.GetRef())
// Fill labelIndexToLocation with -1 :
.Ldc_I4(LabelCount).Stloc(intTmp.GetRef())
.Label(LABEL1)
.Ldloc(intTmp.GetRef())
.Ldc_I4_0()
.Beq(LABEL0.GetRef())
.Ldloc(intTmp.GetRef())
.Ldc_I4(1)
.Sub()
.Stloc(intTmp.GetRef())
.Ldloc(labelIndexToLocation.GetRef())
.Ldloc(intTmp.GetRef())
.Ldc_I4(int.MinValue)
.Stelem_I4()
.Br(LABEL1.GetRef())
.Label(LABEL0)
.Br(POSTCOMPILEINIT_BACK.GetRef());
// Save thread as suspended (stack should already contain label index to suspend)
emit.Label(THREAD_SUSPEND);
StThreadValueByRuntimeLabelIndex();
emit
// Don't add thread if same thread (same label index
// with current input location) already exists in a list.
.Ldloc(labelIndexToLocation.GetRef())
.Ldloca(threadTmp.GetRef())
.Ldfld(LabelIndexField)
.Ldelem_I4()
.Ldloc(inputPump.Index.GetRef())
.Beq(NEXT_THREAD.GetRef())
// Mark label index as visited
.Ldloc(labelIndexToLocation.GetRef())
.Ldloca(threadTmp.GetRef())
.Ldfld(LabelIndexField)
.Ldloc(inputPump.Index.GetRef())
.Stelem_I4()
;
suspendedStack.PushFrom(emit, threadTmp);
emit
.Br(NEXT_THREAD.GetRef())
.Label(RESUME_ALL)
.Swap(suspendedStack.Stack, runningStack.Stack, tmpStack.Stack)
.Swap(suspendedStack.Index, runningStack.Index, tmpStack.Index)
.Label(NEXT_THREAD)
;
runningStack
.StackLoop(
emit,
(emit2, thread) =>
{
emit2
.Ldloca(thread.GetRef())
.Ldfld(LabelIndexField)
.Label(THREAD_DISPATCH)
.Switch(indexToLabel.Select(def => def.GetRef()).ToArray())
.Br(settings.FAILURE.GetRef());
})
;
emit
.Br(NEXT_INPUT.GetRef())
;
emit
.Label(NEXT_INPUT)
;
inputPump.EmitLoopPass(emit, false);
emit
// Check if there are matched threads:
.Do(matchedStack.LdCount)
.Ldc_I4_0()
.Beq(settings.FAILURE.GetRef())
.Br(settings.SUCCESS.GetRef());
}
public INfaVM Match()
{
matchedStack.PushFrom(emit, threadTmp);
emit.Br(NEXT_THREAD.GetRef());
return(this);
}
public void Build(EmitSyntax emit)
{
// Debug.WriteLine("DFA for " + descriptor.Name + ":");
// Debug.WriteLine(dfa);
int failState = dfa.StateCount;
var locals = emit.Locals;
var labels = emit.Labels;
var FIN = labels.Generate();
var current = locals.Generate("ch");
var Lgoto = new Ref<Labels>[dfa.StateCount + 1]; // label for incrementing ch position
var Mgoto = new Ref<Labels>[dfa.StateCount]; // assing ch using current position
var Tgoto = new Ref<Labels>[dfa.StateCount]; // transition dispatching switch-code
for (int i = 0; i != dfa.StateCount; ++i)
{
Lgoto[i] = labels.Generate().GetRef();
Mgoto[i] = labels.Generate().GetRef();
Tgoto[i] = labels.Generate().GetRef();
}
Lgoto[failState] = FIN.GetRef();
emit
.Local(current, emit.Types.Char)
.Ldarg(0) .Ldfld((ScanCursor c) => c.InnerState)
.Switch(Mgoto)
.Br(Lgoto[0])
;
foreach (var S in dfa.EnumerateStates())
{
int state = S.Index;
emit
.Label(Lgoto[state].Def);
if (state != dfa.Start)
{
// ++Cursor
emit
.Ldarg(0) // for Stfld
.Ldarg(0).Ldfld((ScanCursor c) => c.Cursor)
.Ldc_I4_1()
.Add()
.Stfld((ScanCursor c) => c.Cursor)
;
}
// If state is accepring then remember position
// in Marker and save corresponding ActionId.
if (S.IsAccepting)
{
int actionCount = 0;
foreach (var action in S.Actions)
{
emit
.Ldarg(0)
.Ldfld((ScanCursor c) => c.Actions)
.Ldc_I4(actionCount++)
.Ldc_I4(action)
.Stelem_I4()
;
}
emit
.Ldarg(0)
.Ldc_I4(actionCount)
.Stfld((ScanCursor c) => c.ActionCount)
;
emit
.Ldarg(0)
.Ldc_I4(S.EnvelopeId)
.Stfld((ScanCursor c) => c.EnvelopeId)
;
emit
.Ldarg(0)
.Ldarg(0) .Ldfld((ScanCursor c) => c.Cursor)
.Stfld((ScanCursor c) => c.Marker);
// Save line/column information
emit
// cursor.MarkerLine = cursor.CursorLine;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.CursorLine)
.Stfld((ScanCursor c) => c.MarkerLine)
// cursor.MarkerLineStart = cursor.CursorLineStart;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.CursorLineStart)
.Stfld((ScanCursor c) => c.MarkerLineStart)
;
}
if (S.IsNewline)
{
emit
// ++cursor.CursorLine;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.CursorLine)
.Ldc_I4_1()
.Add()
.Stfld((ScanCursor c) => c.CursorLine)
// cursor.CursorLineStart = cursor.Cursor;
.Ldarg(0)
.Ldarg(0)
.Ldfld((ScanCursor c) => c.Cursor)
.Stfld((ScanCursor c) => c.CursorLineStart)
;
}
emit
.Label(Mgoto[state].Def)
// Get current input symbol
.Ldarg(0) .Ldfld((ScanCursor c) => c.Buffer)
.Ldarg(0) .Ldfld((ScanCursor c) => c.Cursor)
.Ldelem_U2()
.Stloc(current.GetRef())
// Label for tunneling
.Label(Tgoto[state].Def)
;
if (S.IsFinal && state != 0)
{
emit
.Br(FIN.GetRef());
continue;
}
int checkSentinelState = failState + 1;
var stateRealTransitions = dfa.EnumerateRealTransitions(S).ToList();
// Find custom sentinel transtion
int customSentinelToState = -1;
var customSentinelTransitionIndex =
stateRealTransitions.FindIndex(pair => pair.Key.Contains(Sentinel));
if (customSentinelTransitionIndex >= 0)
{
customSentinelToState = stateRealTransitions[customSentinelTransitionIndex].Value;
}
// Sentinel check transiiton
var sentinelTransition = new IntArrow<int>(Sentinel, checkSentinelState);
stateRealTransitions.Insert(0, sentinelTransition);
var generator = SwitchGenerator.Sparse(
stateRealTransitions.ToArray(),
failState,
UnicodeIntSetType.UnicodeInterval,
frequency: UnicodeFrequency.Default);
generator.Build(
emit,
il => il.Ldloc(current.GetRef()),
(EmitSyntax il, int value) =>
{
if (value == checkSentinelState)
{
var handleSentinelCharLabel =
(customSentinelToState >= 0)
? Lgoto[customSentinelToState]
: FIN.GetRef();
// return for buffer filling if Cursor == Limit,
// otherwise transite on char
il
.Ldarg(0) .Ldfld((ScanCursor c) => c.Limit)
.Ldarg(0) .Ldfld((ScanCursor c) => c.Cursor)
.Bne_Un(handleSentinelCharLabel)
// Return for buffer filling
.Ldarg(0)
.Ldc_I4(state)
.Stfld((ScanCursor c) => c.InnerState)
.Ldc_I4(1)
.Ret()
;
}
else if (value == failState && S.Tunnel >= 0)
{
// Tunnel-jump to other state and verify current
// input again in that state.
il.Br(Tgoto[S.Tunnel]);
}
else
{
// Transite to the valid or failed state
il.Br(Lgoto[value]);
}
});
}
// Return to the last accepted position and report accept stage
emit
.Label(FIN)
.Ldc_I4(0)
.Ret()
;
}
public EmitSyntax StackLoop(EmitSyntax emit, Action<EmitSyntax, Def<Locals>> emitLoopBody)
{
var labels = emit.Labels;
var START = labels.Generate();
var END = labels.Generate();
var item = emit.Locals.Generate();
emit
.Local(item, itemType)
.Label(START)
.Ldloc(index.GetRef())
.Ldc_I4(0)
.Beq(END.GetRef())
.Do(Pop)
.Stloc(item.GetRef())
;
emitLoopBody(emit, item);
emit
.Br(START.GetRef())
.Label(END)
.Nop();
return emit;
}