// in unreachable code, for instance.
//
- if (warn)
+ bool unreachable = false;
+ if (warn && !ec.UnreachableReported) {
+ ec.UnreachableReported = true;
+ unreachable = true;
ec.Report.Warning (162, 2, loc, "Unreachable code detected");
+ }
ec.StartFlowBranching (FlowBranching.BranchingType.Block, loc);
bool ok = Resolve (ec);
ec.KillFlowBranching ();
+ if (unreachable) {
+ ec.UnreachableReported = false;
+ }
+
return ok;
}
if (ec.CurrentIterator != null) {
Error_ReturnFromIterator (ec);
- } else {
+ } else if (ec.ReturnType != InternalType.ErrorType) {
ec.Report.Error (126, loc,
"An object of a type convertible to `{0}' is required for the return statement",
ec.ReturnType.GetSignatureForError ());
return false;
}
- if (!ec.Switch.GotDefault) {
+ if (ec.Switch.DefaultLabel == null) {
FlowBranchingBlock.Error_UnknownLabel (loc, "default", ec.Report);
return false;
}
protected override void DoEmit (EmitContext ec)
{
- ec.Emit (OpCodes.Br, ec.Switch.DefaultLabel);
+ ec.Emit (OpCodes.Br, ec.Switch.DefaultLabel.GetILLabel (ec));
}
public override object Accept (StructuralVisitor visitor)
res = c;
} else {
TypeSpec type = ec.Switch.SwitchType;
- res = c.TryReduce (ec, type);
+ res = c.Reduce (ec, type);
if (res == null) {
c.Error_ValueCannotBeConverted (ec, type, true);
return false;
#endif
// int assignable_slots;
- bool unreachable_shown;
- bool unreachable;
-
+
public Block (Block parent, Location start, Location end)
: this (parent, 0, start, end)
{
#endregion
- public Block CreateSwitchBlock (Location start)
- {
- // FIXME: Only explicit block should be created
- var new_block = new Block (this, start, start);
- new_block.IsCompilerGenerated = true;
- return new_block;
- }
-
public void SetEndLocation (Location loc)
{
EndLocation = loc;
Block prev_block = ec.CurrentBlock;
bool ok = true;
+ bool unreachable = ec.IsUnreachable;
+ bool prev_unreachable = unreachable;
ec.CurrentBlock = this;
ec.StartFlowBranching (this);
if (s is EmptyStatement)
continue;
- if (!unreachable_shown && !(s is LabeledStatement)) {
+ if (!ec.UnreachableReported && !(s is LabeledStatement) && !(s is SwitchLabel)) {
ec.Report.Warning (162, 2, s.loc, "Unreachable code detected");
- unreachable_shown = true;
+ ec.UnreachableReported = true;
}
-
- Block c_block = s as Block;
- if (c_block != null)
- c_block.unreachable = c_block.unreachable_shown = true;
}
//
if (!s.Resolve (ec)) {
ok = false;
- if (ec.IsInProbingMode)
- break;
+ if (!ec.IsInProbingMode)
+ statements [ix] = new EmptyStatement (s.loc);
- statements [ix] = new EmptyStatement (s.loc);
continue;
}
- if (unreachable && !(s is LabeledStatement) && !(s is Block))
+ if (unreachable && !(s is LabeledStatement) && !(s is SwitchLabel) && !(s is Block))
statements [ix] = new EmptyStatement (s.loc);
unreachable = ec.CurrentBranching.CurrentUsageVector.IsUnreachable;
- if (unreachable && s is LabeledStatement)
- throw new InternalErrorException ("should not happen");
+ if (unreachable) {
+ ec.IsUnreachable = true;
+ } else if (ec.IsUnreachable)
+ ec.IsUnreachable = false;
+ }
+
+ if (unreachable != prev_unreachable) {
+ ec.IsUnreachable = prev_unreachable;
+ ec.UnreachableReported = false;
}
while (ec.CurrentBranching is FlowBranchingLabeled)
public override bool ResolveUnreachable (BlockContext ec, bool warn)
{
- unreachable_shown = true;
- unreachable = true;
-
- if (warn)
+ bool unreachable = false;
+ if (warn && !ec.UnreachableReported) {
+ ec.UnreachableReported = true;
+ unreachable = true;
ec.Report.Warning (162, 2, loc, "Unreachable code detected");
+ }
var fb = ec.StartFlowBranching (FlowBranching.BranchingType.Block, loc);
fb.CurrentUsageVector.IsUnreachable = true;
bool ok = Resolve (ec);
ec.KillFlowBranching ();
+ if (unreachable)
+ ec.UnreachableReported = false;
+
return ok;
}
// Only first storey in path will hold this reference. All children blocks will
// reference it indirectly using $ref field
//
- for (Block b = Original.Explicit.Parent; b != null; b = b.Parent) {
- var s = b.Explicit.AnonymousMethodStorey;
- if (s != null) {
- storey.HoistedThis = s.HoistedThis;
- break;
+ for (Block b = Original.Explicit; b != null; b = b.Parent) {
+ if (b.Parent != null) {
+ var s = b.Parent.Explicit.AnonymousMethodStorey;
+ if (s != null) {
+ storey.HoistedThis = s.HoistedThis;
+ break;
+ }
}
- }
+ if (b.Explicit == b.Explicit.ParametersBlock && b.Explicit.ParametersBlock.StateMachine != null) {
+ storey.HoistedThis = b.Explicit.ParametersBlock.StateMachine.HoistedThis;
+
+ if (storey.HoistedThis != null)
+ break;
+ }
+ }
+
//
- // We are the first storey on path and this has to be hoisted
+ // We are the first storey on path and 'this' has to be hoisted
//
if (storey.HoistedThis == null) {
foreach (ExplicitBlock ref_block in Original.ParametersBlock.TopBlock.ThisReferencesFromChildrenBlock) {
if (block_on_path == null)
continue;
- if (storey.HoistedThis == null)
+ if (storey.HoistedThis == null) {
storey.AddCapturedThisField (ec);
+ }
for (ExplicitBlock b = ref_block; b.AnonymousMethodStorey != storey; b = b.Parent.Explicit) {
if (b.AnonymousMethodStorey != null) {
pb.StateMachine.AddParentStoreyReference (ec, storey);
}
-
+
b.HasCapturedVariable = true;
}
}
// Overwrite original for comparison purposes when linking cross references
// between anonymous methods
//
- Original = source;
+ Original = source.Original;
}
#region Properties
//
// A collision checking between local names
//
+ var variable_block = li.Block.Explicit;
for (int i = 0; i < existing_list.Count; ++i) {
existing = existing_list[i];
Block b = existing.Block.Explicit;
// Collision at same level
- if (li.Block.Explicit == b) {
+ if (variable_block == b) {
li.Block.Error_AlreadyDeclared (name, li);
break;
}
// Collision with parent
- Block parent = li.Block.Explicit;
+ Block parent = variable_block;
while ((parent = parent.Parent) != null) {
if (parent == b) {
li.Block.Error_AlreadyDeclared (name, li, "parent or current");
}
}
- if (!ignoreChildrenBlocks) {
+ if (!ignoreChildrenBlocks && variable_block.Parent != b.Parent) {
// Collision with children
while ((b = b.Parent) != null) {
- if (li.Block.Explicit == b) {
+ if (variable_block == b) {
li.Block.Error_AlreadyDeclared (name, li, "child");
i = existing_list.Count;
break;
if (label != null) {
if (label.Block == b.Original)
return label;
-
- // TODO: Temporary workaround for the switch block implicit label block
- if (label.Block.IsCompilerGenerated && label.Block.Parent == b.Original)
- return label;
} else {
List<LabeledStatement> list = (List<LabeledStatement>) value;
for (int i = 0; i < list.Count; ++i) {
label = list[i];
if (label.Block == b.Original)
return label;
-
- // TODO: Temporary workaround for the switch block implicit label block
- if (label.Block.IsCompilerGenerated && label.Block.Parent == b.Original)
- return label;
}
}
}
}
- public class SwitchLabel {
+ public class SwitchLabel : Statement
+ {
Expression label;
Constant converted;
- readonly Location loc;
Label? il_label;
}
}
+ public bool SectionStart { get; set; }
+
public Label GetILLabel (EmitContext ec)
{
if (il_label == null){
return il_label.Value;
}
+ protected override void DoEmit (EmitContext ec)
+ {
+ ec.MarkLabel (GetILLabel (ec));
+ }
+
+ public override bool Resolve (BlockContext bc)
+ {
+ bc.CurrentBranching.CurrentUsageVector.ResetBarrier ();
+
+ return base.Resolve (bc);
+ }
+
//
// Resolves the expression, reduces it to a literal if possible
// and then converts it to the requested type.
ec.Report.Error (152, loc, "The label `case {0}:' already occurs in this switch statement", label);
}
- public SwitchLabel Clone (CloneContext clonectx)
- {
- if (label == null)
- return this;
-
- return new SwitchLabel (label.Clone (clonectx), loc);
- }
- }
-
- public class SwitchSection {
- public readonly List<SwitchLabel> Labels;
- public readonly Block Block;
-
- public SwitchSection (List<SwitchLabel> labels, Block block)
+ protected override void CloneTo (CloneContext clonectx, Statement target)
{
- Labels = labels;
- Block = block;
+ var t = (SwitchLabel) target;
+ if (label != null)
+ t.label = label.Clone (clonectx);
}
- public SwitchSection Clone (CloneContext clonectx)
+ public override object Accept (StructuralVisitor visitor)
{
- var cloned_labels = new List<SwitchLabel> ();
-
- foreach (SwitchLabel sl in Labels)
- cloned_labels.Add (sl.Clone (clonectx));
-
- return new SwitchSection (cloned_labels, clonectx.LookupBlock (Block));
+ return visitor.Visit (this);
}
}
-
+
public class Switch : Statement
{
// structure used to hold blocks of keys while calculating table switch
}
}
- sealed class LabelMarker : Statement
+ sealed class DispatchStatement : Statement
{
- readonly Switch s;
- readonly List<SwitchLabel> labels;
+ readonly Switch body;
- public LabelMarker (Switch s, List<SwitchLabel> labels)
+ public DispatchStatement (Switch body)
{
- this.s = s;
- this.labels = labels;
+ this.body = body;
}
protected override void CloneTo (CloneContext clonectx, Statement target)
{
+ throw new NotImplementedException ();
}
protected override void DoEmit (EmitContext ec)
{
- foreach (var l in labels) {
- if (l.IsDefault)
- ec.MarkLabel (s.DefaultLabel);
- else
- ec.MarkLabel (l.GetILLabel (ec));
- }
+ body.EmitDispatch (ec);
}
}
- public List<SwitchSection> Sections;
public Expression Expr;
//
//
Dictionary<long, SwitchLabel> labels;
Dictionary<string, SwitchLabel> string_labels;
+ List<SwitchLabel> case_labels;
/// <summary>
/// The governing switch type
/// </summary>
public TypeSpec SwitchType;
- //
- // Computed
- //
- Label default_target;
- Label null_target;
Expression new_expr;
- bool is_constant;
- SwitchSection constant_section;
- SwitchSection default_section;
- SwitchLabel null_section;
+ SwitchLabel case_null;
+ SwitchLabel case_default;
- Statement simple_stmt;
+ Label defaultLabel, nullLabel;
VariableReference value;
ExpressionStatement string_dictionary;
FieldExpr switch_cache_field;
//
Nullable.Unwrap unwrap;
- public Switch (Expression e, ExplicitBlock block, List<SwitchSection> sects, Location l)
+ public Switch (Expression e, ExplicitBlock block, Location l)
{
Expr = e;
this.block = block;
- Sections = sects;
loc = l;
}
}
}
- public Label DefaultLabel {
- get {
- return default_target;
- }
- }
-
- public bool GotDefault {
+ public SwitchLabel DefaultLabel {
get {
- return default_section != null;
+ return case_default;
}
}
// It also returns a hashtable with the keys that we will later
// use to compute the switch tables
//
- bool CheckSwitch (ResolveContext ec)
+ bool ResolveLabels (ResolveContext ec, Constant value)
{
bool error = false;
- if (SwitchType.BuiltinType == BuiltinTypeSpec.Type.String)
- string_labels = new Dictionary<string, SwitchLabel> (Sections.Count + 1);
- else
- labels = new Dictionary<long, SwitchLabel> (Sections.Count + 1);
-
- foreach (SwitchSection ss in Sections){
- foreach (SwitchLabel sl in ss.Labels){
- if (sl.IsDefault){
- if (default_section != null){
- sl.Error_AlreadyOccurs (ec, SwitchType, default_section.Labels [0]);
- error = true;
- }
- default_section = ss;
- continue;
- }
+ if (SwitchType.BuiltinType == BuiltinTypeSpec.Type.String) {
+ string_labels = new Dictionary<string, SwitchLabel> ();
+ } else {
+ labels = new Dictionary<long, SwitchLabel> ();
+ }
+
+ case_labels = new List<SwitchLabel> ();
+ int default_label_index = -1;
+ bool constant_label_found = false;
+
+ for (int i = 0; i < block.Statements.Count; ++i) {
+ var s = block.Statements[i];
+
+ var sl = s as SwitchLabel;
+ if (sl == null) {
+ continue;
+ }
- if (!sl.ResolveAndReduce (ec, SwitchType, IsNullable)) {
+ case_labels.Add (sl);
+
+ if (sl.IsDefault) {
+ if (case_default != null) {
+ sl.Error_AlreadyOccurs (ec, SwitchType, case_default);
error = true;
- continue;
}
-
- try {
- if (string_labels != null) {
- string s = sl.Converted.GetValue () as string;
- if (s == null)
- null_section = sl;
- else
- string_labels.Add (s, sl);
+
+ default_label_index = i;
+ case_default = sl;
+ continue;
+ }
+
+ if (!sl.ResolveAndReduce (ec, SwitchType, IsNullable)) {
+ error = true;
+ continue;
+ }
+
+ try {
+ if (string_labels != null) {
+ string string_value = sl.Converted.GetValue () as string;
+ if (string_value == null)
+ case_null = sl;
+ else
+ string_labels.Add (string_value, sl);
+ } else {
+ if (sl.Converted is NullLiteral) {
+ case_null = sl;
} else {
- if (sl.Converted is NullLiteral) {
- null_section = sl;
- } else {
- labels.Add (sl.Converted.GetValueAsLong (), sl);
- }
+ labels.Add (sl.Converted.GetValueAsLong (), sl);
}
- } catch (ArgumentException) {
- if (string_labels != null)
- sl.Error_AlreadyOccurs (ec, SwitchType, string_labels[(string) sl.Converted.GetValue ()]);
- else
- sl.Error_AlreadyOccurs (ec, SwitchType, labels[sl.Converted.GetValueAsLong ()]);
-
- error = true;
}
+ } catch (ArgumentException) {
+ if (string_labels != null)
+ sl.Error_AlreadyOccurs (ec, SwitchType, string_labels[(string) sl.Converted.GetValue ()]);
+ else
+ sl.Error_AlreadyOccurs (ec, SwitchType, labels[sl.Converted.GetValueAsLong ()]);
+
+ error = true;
+ }
+
+ if (value != null) {
+ var constant_label = constant_label_found ? null : FindLabel (value);
+ if (constant_label == null || constant_label != sl)
+ block.Statements[i] = new EmptyStatement (s.loc);
+ else
+ constant_label_found = true;
}
}
+
+ if (value != null && constant_label_found && default_label_index >= 0)
+ block.Statements[default_label_index] = new EmptyStatement (case_default.loc);
+
return !error;
}
//
void EmitTableSwitch (EmitContext ec, Expression val)
{
- Label lbl_default = default_target;
-
if (labels != null && labels.Count > 0) {
List<LabelsRange> ranges;
if (string_labels != null) {
ranges.Sort ();
}
+ Label lbl_default = defaultLabel;
TypeSpec compare_type = SwitchType.IsEnum ? EnumSpec.GetUnderlyingType (SwitchType) : SwitchType;
for (int range_index = ranges.Count - 1; range_index >= 0; --range_index) {
LabelsRange kb = ranges[range_index];
- lbl_default = (range_index == 0) ? default_target : ec.DefineLabel ();
+ lbl_default = (range_index == 0) ? defaultLabel : ec.DefineLabel ();
// Optimize small ranges using simple equality check
if (kb.Range <= 2) {
foreach (var key in kb.label_values) {
SwitchLabel sl = labels[key];
- if (sl.Converted.IsDefaultValue) {
+ if (sl == case_default || sl == case_null)
+ continue;
+
+ if (sl.Converted.IsZeroInteger) {
val.EmitBranchable (ec, sl.GetILLabel (ec), false);
} else {
val.Emit (ec);
if (ranges.Count > 0)
ec.Emit (OpCodes.Br, lbl_default);
}
-
- // now emit the code for the sections
- bool found_default = false;
-
- foreach (SwitchSection ss in Sections) {
- foreach (SwitchLabel sl in ss.Labels) {
- if (sl.IsDefault) {
- ec.MarkLabel (lbl_default);
- found_default = true;
- if (null_section == null)
- ec.MarkLabel (null_target);
- } else if (sl.Converted.IsNull) {
- ec.MarkLabel (null_target);
- }
-
- ec.MarkLabel (sl.GetILLabel (ec));
- }
-
- ss.Block.Emit (ec);
- }
-
- if (!found_default) {
- ec.MarkLabel (lbl_default);
- if (null_section == null) {
- ec.MarkLabel (null_target);
- }
- }
}
-
+
SwitchLabel FindLabel (Constant value)
{
SwitchLabel sl = null;
if (string_labels != null) {
string s = value.GetValue () as string;
if (s == null) {
- if (null_section != null)
- sl = null_section;
- else if (default_section != null)
- sl = default_section.Labels[0];
+ if (case_null != null)
+ sl = case_null;
+ else if (case_default != null)
+ sl = case_default;
} else {
string_labels.TryGetValue (s, out sl);
}
} else {
if (value is NullLiteral) {
- sl = null_section;
+ sl = case_null;
} else {
labels.TryGetValue (value.GetValueAsLong (), out sl);
}
return sl;
}
- SwitchSection FindSection (SwitchLabel label)
- {
- foreach (SwitchSection ss in Sections){
- foreach (SwitchLabel sl in ss.Labels){
- if (label == sl)
- return ss;
- }
- }
-
- return null;
- }
-
public override bool Resolve (BlockContext ec)
{
Expr = Expr.Resolve (ec);
return false;
}
- if (!CheckSwitch (ec))
- return false;
+ if (block.Statements.Count == 0)
+ return true;
- Switch old_switch = ec.Switch;
- ec.Switch = this;
- ec.Switch.SwitchType = SwitchType;
+ var constant = new_expr as Constant;
- ec.StartFlowBranching (FlowBranching.BranchingType.Switch, loc);
+ if (!ResolveLabels (ec, constant))
+ return false;
- var constant = new_expr as Constant;
- if (constant != null) {
- is_constant = true;
- SwitchLabel label = FindLabel (constant);
- if (label != null)
- constant_section = FindSection (label);
-
- if (constant_section == null)
- constant_section = default_section;
- } else {
+ //
+ // Don't need extra variable for constant switch or switch with
+ // only default case
+ //
+ if (constant == null && (case_labels.Count - (case_default != null ? 1 : 0)) != 0) {
//
- // Store switch expression for comparission purposes
+ // Store switch expression for comparison purposes
//
value = new_expr as VariableReference;
- if (value == null)
+ if (value == null) {
+ // Create temporary variable inside switch scope
+ var current_block = ec.CurrentBlock;
+ ec.CurrentBlock = Block;
value = TemporaryVariableReference.Create (SwitchType, ec.CurrentBlock, loc);
+ value.Resolve (ec);
+ ec.CurrentBlock = current_block;
+ }
}
- bool first = true;
- bool ok = true;
- foreach (SwitchSection ss in Sections){
- if (!first)
- ec.CurrentBranching.CreateSibling (
- null, FlowBranching.SiblingType.SwitchSection);
- else
- first = false;
+ Switch old_switch = ec.Switch;
+ ec.Switch = this;
+ ec.Switch.SwitchType = SwitchType;
- if (is_constant && (ss != constant_section)) {
- // If we're a constant switch, we're only emitting
- // one single section - mark all the others as
- // unreachable.
- ec.CurrentBranching.CurrentUsageVector.Goto ();
- if (!ss.Block.ResolveUnreachable (ec, true)) {
- ok = false;
- }
- } else {
- if (!ss.Block.Resolve (ec))
- ok = false;
- }
- }
+ ec.StartFlowBranching (FlowBranching.BranchingType.Switch, loc);
- if (default_section == null)
- ec.CurrentBranching.CreateSibling (null, FlowBranching.SiblingType.SwitchSection);
+ ec.CurrentBranching.CurrentUsageVector.Goto ();
+
+ var ok = block.Resolve (ec);
+
+ if (case_default == null)
+ ec.CurrentBranching.CurrentUsageVector.ResetBarrier ();
ec.EndFlowBranching ();
ec.Switch = old_switch;
if (!ok)
return false;
- if (!is_constant) {
- if (SwitchType.BuiltinType == BuiltinTypeSpec.Type.String) {
- if (string_labels.Count < 7)
- ResolveSimpleSwitch (ec);
- else
- ResolveStringSwitchMap (ec);
- } else if (labels.Count < 3 && !IsNullable) {
- ResolveSimpleSwitch (ec);
- }
+ if (constant == null && SwitchType.BuiltinType == BuiltinTypeSpec.Type.String && string_labels.Count > 6) {
+ ResolveStringSwitchMap (ec);
}
+ //
+ // Needed to emit anonymous storey initialization before
+ // any generated switch dispatch
+ //
+ block.AddScopeStatement (new DispatchStatement (this));
+
return true;
}
return sl;
}
- //
- // Prepares switch using simple if/else comparison for small label count (4 + optional default)
- //
- void ResolveSimpleSwitch (BlockContext bc)
- {
- simple_stmt = default_section != null ? default_section.Block : null;
-
- for (int i = Sections.Count - 1; i >= 0; --i) {
- var s = Sections[i];
-
- if (s == default_section) {
- s.Block.AddScopeStatement (new LabelMarker (this, s.Labels));
- continue;
- }
-
- s.Block.AddScopeStatement (new LabelMarker (this, s.Labels));
-
- Expression cond = null;
- for (int ci = 0; ci < s.Labels.Count; ++ci) {
- var e = new Binary (Binary.Operator.Equality, value, s.Labels[ci].Converted);
-
- if (ci > 0) {
- cond = new Binary (Binary.Operator.LogicalOr, cond, e);
- } else {
- cond = e;
- }
- }
-
- //
- // Compiler generated, hide from symbol file
- //
- simple_stmt = new If (cond, s.Block, simple_stmt, Location.Null);
- }
-
- // It's null for empty switch
- if (simple_stmt != null)
- simple_stmt.Resolve (bc);
- }
-
//
// Converts string switch into string hashtable
//
ctype.AddField (field);
var init = new List<Expression> ();
- int counter = 0;
+ int counter = -1;
labels = new Dictionary<long, SwitchLabel> (string_labels.Count);
string value = null;
- foreach (SwitchSection section in Sections) {
- bool contains_label = false;
- foreach (SwitchLabel sl in section.Labels) {
- if (sl.IsDefault || sl.Converted.IsNull)
- continue;
- if (!contains_label) {
- labels.Add (counter, sl);
- contains_label = true;
- }
+ foreach (SwitchLabel sl in case_labels) {
- value = (string) sl.Converted.GetValue ();
- var init_args = new List<Expression> (2);
- init_args.Add (new StringLiteral (ec.BuiltinTypes, value, sl.Location));
+ if (sl.SectionStart)
+ labels.Add (++counter, sl);
- sl.Converted = new IntConstant (ec.BuiltinTypes, counter, loc);
- init_args.Add (sl.Converted);
+ if (sl == case_default || sl == case_null)
+ continue;
- init.Add (new CollectionElementInitializer (init_args, loc));
- }
+ value = (string) sl.Converted.GetValue ();
+ var init_args = new List<Expression> (2);
+ init_args.Add (new StringLiteral (ec.BuiltinTypes, value, sl.Location));
- //
- // Don't add empty sections
- //
- if (contains_label)
- ++counter;
- }
+ sl.Converted = new IntConstant (ec.BuiltinTypes, counter, loc);
+ init_args.Add (sl.Converted);
+ init.Add (new CollectionElementInitializer (init_args, loc));
+ }
+
Arguments args = new Arguments (1);
args.Add (new Argument (new IntConstant (ec.BuiltinTypes, init.Count, loc)));
Expression initializer = new NewInitialize (string_dictionary_type, args,
//
// Skip initialization when value is null
//
- value.EmitBranchable (ec, null_target, false);
+ value.EmitBranchable (ec, nullLabel, false);
//
// Check if string dictionary is initialized and initialize
//
// A value was not found, go to default case
//
- get_item.EmitBranchable (ec, default_target, false);
+ get_item.EmitBranchable (ec, defaultLabel, false);
} else {
Arguments get_value_args = new Arguments (1);
get_value_args.Add (new Argument (value));
LocalTemporary get_item_object = new LocalTemporary (ec.BuiltinTypes.Object);
get_item_object.EmitAssign (ec, get_item, true, false);
- ec.Emit (OpCodes.Brfalse, default_target);
+ ec.Emit (OpCodes.Brfalse, defaultLabel);
ExpressionStatement get_item_int = (ExpressionStatement) new SimpleAssign (string_switch_variable,
new Cast (new TypeExpression (ec.BuiltinTypes.Int, loc), get_item_object, loc)).Resolve (rc);
string_switch_variable.Release (ec);
}
- protected override void DoEmit (EmitContext ec)
+ //
+ // Emits switch using simple if/else comparison for small label count (4 + optional default)
+ //
+ void EmitShortSwitch (EmitContext ec)
{
- // Workaround broken flow-analysis
- block.HasUnreachableClosingBrace = true;
+ MethodSpec equal_method = null;
+ if (SwitchType.BuiltinType == BuiltinTypeSpec.Type.String) {
+ equal_method = ec.Module.PredefinedMembers.StringEqual.Resolve (loc);
+ }
+
+ if (equal_method != null) {
+ value.EmitBranchable (ec, nullLabel, false);
+ }
+
+ for (int i = 0; i < case_labels.Count; ++i) {
+ var label = case_labels [i];
+ if (label == case_default || label == case_null)
+ continue;
+
+ var constant = label.Converted;
+
+ if (equal_method != null) {
+ value.Emit (ec);
+ constant.Emit (ec);
+
+ var call = new CallEmitter ();
+ call.EmitPredefined (ec, equal_method, new Arguments (0));
+ ec.Emit (OpCodes.Brtrue, label.GetILLabel (ec));
+ continue;
+ }
+
+ if (constant.IsZeroInteger && constant.Type.BuiltinType != BuiltinTypeSpec.Type.Long && constant.Type.BuiltinType != BuiltinTypeSpec.Type.ULong) {
+ value.EmitBranchable (ec, label.GetILLabel (ec), false);
+ continue;
+ }
+
+ value.Emit (ec);
+ constant.Emit (ec);
+ ec.Emit (OpCodes.Beq, label.GetILLabel (ec));
+ }
+
+ ec.Emit (OpCodes.Br, defaultLabel);
+ }
+
+ void EmitDispatch (EmitContext ec)
+ {
+ if (value == null) {
+ //
+ // Constant switch, we already done the work
+ //
+ return;
+ }
//
- // Needed to emit anonymous storey initialization
- // Otherwise it does not contain any statements for now
+ // Mark sequence point explicitly to switch
//
- block.Emit (ec);
+ ec.Mark (block.StartLocation);
+ block.IsCompilerGenerated = true;
- default_target = ec.DefineLabel ();
- null_target = ec.DefineLabel ();
-
- if (IsNullable) {
- unwrap.EmitCheck (ec);
- ec.Emit (OpCodes.Brfalse, null_target);
- value.EmitAssign (ec, new_expr, false, false);
- } else if (new_expr != value && !is_constant) {
- value.EmitAssign (ec, new_expr, false, false);
+ if (string_dictionary != null) {
+ DoEmitStringSwitch (ec);
+ } else if (case_labels.Count < 4 || string_labels != null) {
+ EmitShortSwitch (ec);
+ } else {
+ EmitTableSwitch (ec, value);
}
+ }
+
+ protected override void DoEmit (EmitContext ec)
+ {
+ // Workaround broken flow-analysis
+ block.HasUnreachableClosingBrace = true;
//
// Setup the codegen context
//
Label old_end = ec.LoopEnd;
Switch old_switch = ec.Switch;
-
+
ec.LoopEnd = ec.DefineLabel ();
ec.Switch = this;
- // Emit Code.
- if (is_constant) {
- if (constant_section != null)
- constant_section.Block.Emit (ec);
- } else if (string_dictionary != null) {
- DoEmitStringSwitch (ec);
- } else if (simple_stmt != null) {
- simple_stmt.Emit (ec);
- } else {
- EmitTableSwitch (ec, value);
+ defaultLabel = case_default == null ? ec.LoopEnd : case_default.GetILLabel (ec);
+ nullLabel = case_null == null ? defaultLabel : case_null.GetILLabel (ec);
+
+ if (value != null) {
+ ec.Mark (loc);
+ if (IsNullable) {
+ unwrap.EmitCheck (ec);
+ ec.Emit (OpCodes.Brfalse, nullLabel);
+ value.EmitAssign (ec, new_expr, false, false);
+ } else if (new_expr != value) {
+ value.EmitAssign (ec, new_expr, false, false);
+ }
}
+ block.Emit (ec);
+
// Restore context state.
ec.MarkLabel (ec.LoopEnd);
Switch target = (Switch) t;
target.Expr = Expr.Clone (clonectx);
- target.Sections = new List<SwitchSection> ();
- foreach (SwitchSection ss in Sections){
- target.Sections.Add (ss.Clone (clonectx));
- }
+ target.block = (ExplicitBlock) block.Clone (clonectx);
}
public override object Accept (StructuralVisitor visitor)
if (mg != null) {
mg.InstanceExpression = expr;
Arguments args = new Arguments (0);
- mg = mg.OverloadResolve (rc, ref args, this, OverloadResolver.Restrictions.None);
+ mg = mg.OverloadResolve (rc, ref args, this, OverloadResolver.Restrictions.ProbingOnly);
// For ambiguous GetEnumerator name warning CS0278 was reported, but Option 2 could still apply
if (ambiguous_getenumerator_name)
if (!gen_ienumerable.Define ())
gen_ienumerable = null;
- do {
- var ifaces = t.Interfaces;
- if (ifaces != null) {
- foreach (var iface in ifaces) {
- if (gen_ienumerable != null && iface.MemberDefinition == gen_ienumerable.TypeSpec.MemberDefinition) {
- if (iface_candidate != null && iface_candidate != rc.Module.PredefinedMembers.IEnumerableGetEnumerator) {
- rc.Report.SymbolRelatedToPreviousError (expr.Type);
- rc.Report.Error (1640, loc,
- "foreach statement cannot operate on variables of type `{0}' because it contains multiple implementation of `{1}'. Try casting to a specific implementation",
- expr.Type.GetSignatureForError (), gen_ienumerable.TypeSpec.GetSignatureForError ());
-
- return null;
- }
-
- // TODO: Cache this somehow
- iface_candidate = new PredefinedMember<MethodSpec> (rc.Module, iface,
- MemberFilter.Method ("GetEnumerator", 0, ParametersCompiled.EmptyReadOnlyParameters, null));
-
- continue;
+ var ifaces = t.Interfaces;
+ if (ifaces != null) {
+ foreach (var iface in ifaces) {
+ if (gen_ienumerable != null && iface.MemberDefinition == gen_ienumerable.TypeSpec.MemberDefinition) {
+ if (iface_candidate != null && iface_candidate != rc.Module.PredefinedMembers.IEnumerableGetEnumerator) {
+ rc.Report.SymbolRelatedToPreviousError (expr.Type);
+ rc.Report.Error (1640, loc,
+ "foreach statement cannot operate on variables of type `{0}' because it contains multiple implementation of `{1}'. Try casting to a specific implementation",
+ expr.Type.GetSignatureForError (), gen_ienumerable.TypeSpec.GetSignatureForError ());
+
+ return null;
}
- if (iface.BuiltinType == BuiltinTypeSpec.Type.IEnumerable && iface_candidate == null) {
- iface_candidate = rc.Module.PredefinedMembers.IEnumerableGetEnumerator;
- }
- }
- }
+ // TODO: Cache this somehow
+ iface_candidate = new PredefinedMember<MethodSpec> (rc.Module, iface,
+ MemberFilter.Method ("GetEnumerator", 0, ParametersCompiled.EmptyReadOnlyParameters, null));
- if (t.IsGenericParameter)
- t = t.BaseType;
- else
- t = null;
+ continue;
+ }
- } while (t != null);
+ if (iface.BuiltinType == BuiltinTypeSpec.Type.IEnumerable && iface_candidate == null) {
+ iface_candidate = rc.Module.PredefinedMembers.IEnumerableGetEnumerator;
+ }
+ }
+ }
if (iface_candidate == null) {
if (expr.Type != InternalType.ErrorType) {
projects / mono.git / blobdiff