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提交 eefa365f 编写于 作者: N Neal Gafter
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Change typeswitch lowering per code review comments. 

Moved a PROTOTYPE comment to issue #12431, and report an unimplemented
error message rather than crashing the compiler when switching on float, double,
or decimal.
上级 1ea21c70
隐藏空白更改
内联 并排
Showing with 92 addition and 84 deletion
src/Compilers/CSharp/Portable/Binder/SwitchBinder.cs
浏览文件 @ eefa365f
......@@ -14,16 +14,16 @@ namespace Microsoft.CodeAnalysis.CSharp
{
internal partial class SwitchBinder : LocalScopeBinder
{
protected readonly SwitchStatementSyntax _switchSyntax;
protected readonly GeneratedLabelSymbol _breakLabel;
protected readonly SwitchStatementSyntax SwitchSyntax;
private readonly GeneratedLabelSymbol _breakLabel;
private BoundExpression _switchGoverningExpression;
private DiagnosticBag _switchGoverningDiagnostics;
protected SwitchBinder(Binder next, SwitchStatementSyntax switchSyntax)
: base(next)
{
_switchSyntax = switchSyntax;
SwitchSyntax = switchSyntax;
_breakLabel = new GeneratedLabelSymbol("break");
}
......@@ -31,9 +31,11 @@ internal static SwitchBinder Create(Binder next, SwitchStatementSyntax switchSyn
{
var parseOptions = switchSyntax?.SyntaxTree?.Options as CSharpParseOptions;
return
// in C# 6 and earlier, we use the old binder. In C# 7 and later, we use the new binder which
// In C# 6 and earlier, we use the old binder. In C# 7 and later, we use the new binder which
// is capable of binding both the old and new syntax. However, the new binder does not yet
// lead to a translation that fully supports edit-and-continue.
// lead to a translation that fully supports edit-and-continue, so it delegates to the C# 6
// binder when it can. The "typeswitch" feature flag forces the use of the C# 7 switch binder
// for all operations; we use it to enhance test coverage.
(parseOptions?.IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching) != false || parseOptions?.Features.ContainsKey("typeswitch") != false)
? new PatternSwitchBinder(next, switchSyntax)
: new SwitchBinder(next, switchSyntax);
......@@ -41,7 +43,7 @@ internal static SwitchBinder Create(Binder next, SwitchStatementSyntax switchSyn
protected bool PatternsEnabled =>
((CSharpParseOptions)this._switchSyntax.SyntaxTree.Options)?.IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching) != false;
((CSharpParseOptions)SwitchSyntax.SyntaxTree.Options)?.IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching) != false;
protected BoundExpression SwitchGoverningExpression
{
......@@ -49,12 +51,10 @@ protected BoundExpression SwitchGoverningExpression
{
if (_switchGoverningExpression == null)
{
var switchGoverningDiagnostics = new DiagnosticBag();
var boundSwitchExpression = BindSwitchExpression(_switchSyntax.Expression, switchGoverningDiagnostics);
_switchGoverningDiagnostics = switchGoverningDiagnostics;
Interlocked.CompareExchange(ref _switchGoverningExpression, boundSwitchExpression, null);
EnsureSwitchGoverningExpressionAndDiagnosticsBound();
}
Debug.Assert(_switchGoverningExpression != null);
return _switchGoverningExpression;
}
}
......@@ -65,11 +65,19 @@ protected DiagnosticBag SwitchGoverningDiagnostics
{
get
{
var discarded = SwitchGoverningExpression;
EnsureSwitchGoverningExpressionAndDiagnosticsBound();
return _switchGoverningDiagnostics;
}
}
private void EnsureSwitchGoverningExpressionAndDiagnosticsBound()
{
var switchGoverningDiagnostics = new DiagnosticBag();
var boundSwitchExpression = BindSwitchExpression(SwitchSyntax.Expression, switchGoverningDiagnostics);
_switchGoverningDiagnostics = switchGoverningDiagnostics;
Interlocked.CompareExchange(ref _switchGoverningExpression, boundSwitchExpression, null);
}
// Dictionary for the switch case/default labels.
// Case labels with a non-null constant value are indexed on their ConstantValue.
// Default label(s) are indexed on a special DefaultKey object.
......@@ -102,7 +110,7 @@ protected DiagnosticBag SwitchGoverningDiagnostics
object key;
var constantValue = label.SwitchCaseLabelConstant;
if (constantValue != (object)null && !constantValue.IsBad)
if ((object)constantValue != null && !constantValue.IsBad)
{
// Case labels with a non-null constant value are indexed on their ConstantValue.
key = KeyForConstant(constantValue);
......@@ -118,14 +126,11 @@ protected DiagnosticBag SwitchGoverningDiagnostics
key = label.IdentifierNodeOrToken.AsNode();
}
// If there is a duplicate label, ignore it. It will be reported when binding the switch label.
if (!map.ContainsKey(key))
{
map.Add(key, label);
}
else
{
// If there is a duplicate label, ignore it. It will be reported when binding the switch label.
}
}
return map;
......@@ -135,7 +140,7 @@ override protected ImmutableArray<LocalSymbol> BuildLocals()
{
var builder = ArrayBuilder<LocalSymbol>.GetInstance();
foreach (var section in _switchSyntax.Sections)
foreach (var section in SwitchSyntax.Sections)
{
builder.AddRange(BuildLocals(section.Statements));
}
......@@ -147,7 +152,7 @@ protected override ImmutableArray<LocalFunctionSymbol> BuildLocalFunctions()
{
var builder = ArrayBuilder<LocalFunctionSymbol>.GetInstance();
foreach (var section in _switchSyntax.Sections)
foreach (var section in SwitchSyntax.Sections)
{
builder.AddRange(BuildLocalFunctions(section.Statements));
}
......@@ -178,11 +183,10 @@ protected override ImmutableArray<LabelSymbol> BuildLabels()
ArrayBuilder<LabelSymbol> labels = ArrayBuilder<LabelSymbol>.GetInstance();
DiagnosticBag tempDiagnosticBag = DiagnosticBag.GetInstance();
TypeSymbol switchGoverningType = this.SwitchGoverningType;
foreach (var section in _switchSyntax.Sections)
foreach (var section in SwitchSyntax.Sections)
{
// add switch case/default labels
BuildSwitchLabels(switchGoverningType, section.Labels, GetBinder(section), labels, tempDiagnosticBag);
BuildSwitchLabels(section.Labels, GetBinder(section), labels, tempDiagnosticBag);
// add regular labels from the statements in the switch section
BuildLabels(section.Statements, ref labels);
......@@ -200,7 +204,7 @@ internal override bool IsLabelsScopeBinder
}
}
private void BuildSwitchLabels(TypeSymbol switchGoverningType, SyntaxList<SwitchLabelSyntax> labelsSyntax, Binder sectionBinder, ArrayBuilder<LabelSymbol> labels, DiagnosticBag tempDiagnosticBag)
private void BuildSwitchLabels(SyntaxList<SwitchLabelSyntax> labelsSyntax, Binder sectionBinder, ArrayBuilder<LabelSymbol> labels, DiagnosticBag tempDiagnosticBag)
{
// add switch case/default labels
foreach (var labelSyntax in labelsSyntax)
......@@ -213,7 +217,7 @@ private void BuildSwitchLabels(TypeSymbol switchGoverningType, SyntaxList<Switch
var caseLabel = (CaseSwitchLabelSyntax)labelSyntax;
Debug.Assert(caseLabel.Value != null);
var boundLabelExpression = sectionBinder.BindValue(caseLabel.Value, tempDiagnosticBag, BindValueKind.RValue);
boundLabelExpression = ConvertCaseExpression(switchGoverningType, labelSyntax, boundLabelExpression, sectionBinder, ref boundLabelConstantOpt, tempDiagnosticBag);
boundLabelExpression = ConvertCaseExpression(labelSyntax, boundLabelExpression, sectionBinder, ref boundLabelConstantOpt, tempDiagnosticBag);
break;
default:
......@@ -226,7 +230,7 @@ private void BuildSwitchLabels(TypeSymbol switchGoverningType, SyntaxList<Switch
}
}
protected BoundExpression ConvertCaseExpression(TypeSymbol switchGoverningType, CSharpSyntaxNode node, BoundExpression caseExpression, Binder sectionBinder, ref ConstantValue constantValueOpt, DiagnosticBag diagnostics, bool isGotoCaseExpr = false)
protected BoundExpression ConvertCaseExpression(CSharpSyntaxNode node, BoundExpression caseExpression, Binder sectionBinder, ref ConstantValue constantValueOpt, DiagnosticBag diagnostics, bool isGotoCaseExpr = false)
{
if (isGotoCaseExpr)
{
......@@ -242,27 +246,27 @@ protected BoundExpression ConvertCaseExpression(TypeSymbol switchGoverningType,
// instead of an error. See test "CS0469_NoImplicitConversionWarning".
HashSet<DiagnosticInfo> useSiteDiagnostics = null;
Conversion conversion = Conversions.ClassifyConversionFromExpression(caseExpression, switchGoverningType, ref useSiteDiagnostics);
Conversion conversion = Conversions.ClassifyConversionFromExpression(caseExpression, SwitchGoverningType, ref useSiteDiagnostics);
diagnostics.Add(node, useSiteDiagnostics);
if (!conversion.IsValid)
{
GenerateImplicitConversionError(diagnostics, node, conversion, caseExpression, switchGoverningType);
GenerateImplicitConversionError(diagnostics, node, conversion, caseExpression, SwitchGoverningType);
}
else if (!conversion.IsImplicit)
{
diagnostics.Add(ErrorCode.WRN_GotoCaseShouldConvert, node.Location, switchGoverningType);
diagnostics.Add(ErrorCode.WRN_GotoCaseShouldConvert, node.Location, SwitchGoverningType);
}
caseExpression = CreateConversion(caseExpression, conversion, switchGoverningType, diagnostics);
caseExpression = CreateConversion(caseExpression, conversion, SwitchGoverningType, diagnostics);
}
return ConvertPatternExpression(switchGoverningType, node, caseExpression, ref constantValueOpt, diagnostics);
return ConvertPatternExpression(SwitchGoverningType, node, caseExpression, ref constantValueOpt, diagnostics);
}
private static readonly object s_nullKey = new object();
protected static object KeyForConstant(ConstantValue constantValue)
{
Debug.Assert(constantValue != (object)null);
Debug.Assert((object)constantValue != null);
return constantValue.IsNull ? s_nullKey : constantValue.Value;
}
......@@ -273,7 +277,7 @@ protected SourceLabelSymbol FindMatchingSwitchCaseLabel(ConstantValue constantVa
// Invalid case labels (with null constant value) are indexed on the label syntax.
object key;
if (constantValue != (object)null && !constantValue.IsBad)
if ((object)constantValue != null && !constantValue.IsBad)
{
key = KeyForConstant(constantValue);
}
......@@ -303,7 +307,7 @@ private SourceLabelSymbol FindMatchingSwitchLabel(object key)
SourceLabelSymbol label;
if (labelsMap.TryGetValue(key, out label))
{
Debug.Assert(label != (object)null);
Debug.Assert((object)label != null);
return label;
}
}
......@@ -313,7 +317,7 @@ private SourceLabelSymbol FindMatchingSwitchLabel(object key)
internal override ImmutableArray<LocalSymbol> GetDeclaredLocalsForScope(CSharpSyntaxNode scopeDesignator)
{
if (_switchSyntax == scopeDesignator)
if (SwitchSyntax == scopeDesignator)
{
return this.Locals;
}
......@@ -323,7 +327,7 @@ internal override ImmutableArray<LocalSymbol> GetDeclaredLocalsForScope(CSharpSy
internal override ImmutableArray<LocalFunctionSymbol> GetDeclaredLocalFunctionsForScope(CSharpSyntaxNode scopeDesignator)
{
if (_switchSyntax == scopeDesignator)
if (SwitchSyntax == scopeDesignator)
{
return this.LocalFunctions;
}
......@@ -335,7 +339,7 @@ internal override SyntaxNode ScopeDesignator
{
get
{
return _switchSyntax;
return SwitchSyntax;
}
}
......@@ -343,7 +347,7 @@ internal override SyntaxNode ScopeDesignator
internal override BoundStatement BindSwitchExpressionAndSections(SwitchStatementSyntax node, Binder originalBinder, DiagnosticBag diagnostics)
{
Debug.Assert(_switchSyntax.Equals(node));
Debug.Assert(SwitchSyntax.Equals(node));
// Bind switch expression and set the switch governing type.
var boundSwitchExpression = this.SwitchGoverningExpression;
......@@ -388,7 +392,7 @@ private BoundExpression BindSwitchExpression(ExpressionSyntax node, DiagnosticBa
//
// The "x" in "switch(x)" refers to this.x, not the local x that is in scope inside the switch block.
Debug.Assert(node == _switchSyntax.Expression);
Debug.Assert(node == SwitchSyntax.Expression);
var binder = this.GetBinder(node);
Debug.Assert(binder != null);
......@@ -475,7 +479,7 @@ private LabelSymbol BindConstantJumpTarget(ConstantValue constantValue, CSharpSy
// value, that label is set as the target.
SourceLabelSymbol labelSymbol = FindMatchingSwitchCaseLabel(constantValue, syntax);
if (labelSymbol != (object)null)
if ((object)labelSymbol != null)
{
boundLabel = labelSymbol;
}
......@@ -485,7 +489,7 @@ private LabelSymbol BindConstantJumpTarget(ConstantValue constantValue, CSharpSy
// switch statement and set that as the target label.
labelSymbol = GetDefaultLabel();
if (labelSymbol != (object)null)
if ((object)labelSymbol != null)
{
boundLabel = labelSymbol;
}
......@@ -572,7 +576,7 @@ private BoundSwitchLabel BindSwitchSectionLabel(SwitchLabelSyntax node, Binder s
var caseLabelSyntax = (CaseSwitchLabelSyntax)node;
// Bind the label case expression
boundLabelExpressionOpt = sectionBinder.BindValue(caseLabelSyntax.Value, diagnostics, BindValueKind.RValue);
boundLabelExpressionOpt = ConvertCaseExpression(switchGoverningType, caseLabelSyntax, boundLabelExpressionOpt, sectionBinder, ref labelExpressionConstant, diagnostics);
boundLabelExpressionOpt = ConvertCaseExpression(caseLabelSyntax, boundLabelExpressionOpt, sectionBinder, ref labelExpressionConstant, diagnostics);
// Check for bind errors
hasErrors = hasErrors || boundLabelExpressionOpt.HasAnyErrors;
......@@ -585,7 +589,7 @@ private BoundSwitchLabel BindSwitchSectionLabel(SwitchLabelSyntax node, Binder s
hasErrors = true;
}
if (!hasErrors && labelExpressionConstant != (object)null && FindMatchingSwitchCaseLabel(labelExpressionConstant, caseLabelSyntax) != label)
if (!hasErrors && (object)labelExpressionConstant != null && FindMatchingSwitchCaseLabel(labelExpressionConstant, caseLabelSyntax) != label)
{
diagnostics.Add(ErrorCode.ERR_DuplicateCaseLabel, node.Location, labelExpressionConstant?.GetValueToDisplay() ?? label.Name);
hasErrors = true;
......@@ -629,7 +633,6 @@ internal BoundStatement BindGotoCaseOrDefault(GotoStatementSyntax node, Binder g
if (!node.HasErrors)
{
ConstantValue gotoCaseExpressionConstant = null;
TypeSymbol switchGoverningType = SwitchGoverningType;
bool hasErrors = false;
SourceLabelSymbol matchedLabelSymbol;
......@@ -648,7 +651,7 @@ internal BoundStatement BindGotoCaseOrDefault(GotoStatementSyntax node, Binder g
// Bind the goto case expression
gotoCaseExpressionOpt = gotoBinder.BindValue(node.Expression, diagnostics, BindValueKind.RValue);
gotoCaseExpressionOpt = ConvertCaseExpression(switchGoverningType, node, gotoCaseExpressionOpt, gotoBinder,
gotoCaseExpressionOpt = ConvertCaseExpression(node, gotoCaseExpressionOpt, gotoBinder,
ref gotoCaseExpressionConstant, diagnostics, isGotoCaseExpr: true);
// Check for bind errors
......@@ -670,7 +673,7 @@ internal BoundStatement BindGotoCaseOrDefault(GotoStatementSyntax node, Binder g
matchedLabelSymbol = GetDefaultLabel();
}
if (matchedLabelSymbol == (object)null)
if ((object)matchedLabelSymbol == null)
{
if (!hasErrors)
{
......
src/Compilers/CSharp/Portable/Binder/SwitchBinder_BindPatternSwitch.cs
浏览文件 @ eefa365f
......@@ -33,11 +33,11 @@ private bool IsPatternSwitch
{
if (_isPatternSwitch == null)
{
var parseOptions = _switchSyntax?.SyntaxTree?.Options as CSharpParseOptions;
var parseOptions = SwitchSyntax?.SyntaxTree?.Options as CSharpParseOptions;
_isPatternSwitch =
(parseOptions?.IsFeatureEnabled(MessageID.IDS_FeaturePatternMatching) != false &&
(parseOptions?.Features.ContainsKey("typeswitch") == true ||
IsPatternSwitchSyntax(_switchSyntax) ||
IsPatternSwitchSyntax(SwitchSyntax) ||
!SwitchGoverningType.IsValidV6SwitchGoverningType()));
}
......@@ -63,7 +63,7 @@ internal override BoundStatement BindSwitchExpressionAndSections(SwitchStatement
// If it is a valid C# 6 switch statement, we use the old binder to bind it.
if (!IsPatternSwitch) return base.BindSwitchExpressionAndSections(node, originalBinder, diagnostics);
Debug.Assert(_switchSyntax.Equals(node));
Debug.Assert(SwitchSyntax.Equals(node));
// Bind switch expression and set the switch governing type.
var boundSwitchExpression = SwitchGoverningExpression;
......@@ -135,7 +135,7 @@ private ImmutableArray<BoundPatternSwitchSection> BindPatternSwitchSections(Boun
node, boundSwitchExpression, boundSwitchExpression.Type, caseLabelSyntax.Value, node.HasErrors, diagnostics, out wasExpression, wasSwitchCase: true);
bool hasErrors = pattern.HasErrors;
var constantValue = pattern.ConstantValue;
if (!hasErrors && constantValue != (object)null && this.FindMatchingSwitchCaseLabel(constantValue, caseLabelSyntax) != label)
if (!hasErrors && (object)constantValue != null && this.FindMatchingSwitchCaseLabel(constantValue, caseLabelSyntax) != label)
{
diagnostics.Add(ErrorCode.ERR_DuplicateCaseLabel, node.Location, pattern.ConstantValue.GetValueToDisplay() ?? label.Name);
hasErrors = true;
......
src/Compilers/CSharp/Portable/Lowering/LocalRewriter/LocalRewriter_PatternSwitchStatement.cs
浏览文件 @ eefa365f
......@@ -9,6 +9,7 @@
using System.Collections.Generic;
using System;
using Roslyn.Utilities;
using Microsoft.CodeAnalysis.CSharp;
namespace Microsoft.CodeAnalysis.CSharp
{
......@@ -19,17 +20,16 @@ public override BoundNode VisitPatternSwitchStatement(BoundPatternSwitchStatemen
_factory.Syntax = node.Syntax;
var pslr = new PatternSwitchLocalRewriter(this, node);
var expression = VisitExpression(node.Expression);
var result = ArrayBuilder<BoundStatement>.GetInstance();
// output the decision tree part
pslr.LowerDecisionTree(expression, node.DecisionTree);
var result = ArrayBuilder<BoundStatement>.GetInstance();
result.AddRange(pslr.LoweredDecisionTree);
pslr.LowerDecisionTree(expression, node.DecisionTree, result);
// if the endpoint is reachable, we exit the switch
if (!node.DecisionTree.MatchIsComplete) result.Add(_factory.Goto(node.BreakLabel));
// at this point the end of result is unreachable.
// output the sections of code (that were reachable)
// output the sections of code
foreach (var section in node.SwitchSections)
{
// Start with the part of the decision tree that is in scope of the section variables.
......@@ -60,7 +60,8 @@ private class PatternSwitchLocalRewriter
public readonly HashSet<LocalSymbol> DeclaredTempSet = new HashSet<LocalSymbol>();
public readonly ArrayBuilder<LocalSymbol> DeclaredTemps = ArrayBuilder<LocalSymbol>.GetInstance();
public readonly Dictionary<BoundPatternSwitchSection, ArrayBuilder<BoundStatement>> SwitchSections = new Dictionary<BoundPatternSwitchSection, ArrayBuilder<BoundStatement>>();
public ArrayBuilder<BoundStatement> LoweredDecisionTree = ArrayBuilder<BoundStatement>.GetInstance();
private ArrayBuilder<BoundStatement> _loweredDecisionTree = ArrayBuilder<BoundStatement>.GetInstance();
private readonly SyntheticBoundNodeFactory _factory;
public PatternSwitchLocalRewriter(LocalRewriter localRewriter, BoundPatternSwitchStatement node)
......@@ -76,15 +77,15 @@ public PatternSwitchLocalRewriter(LocalRewriter localRewriter, BoundPatternSwitc
/// <summary>
/// Lower the given decision tree into the given statement builder.
/// </summary>
private void LowerDecisionTree(BoundExpression expression, DecisionTree decisionTree, ArrayBuilder<BoundStatement> loweredDecisionTree)
public void LowerDecisionTree(BoundExpression expression, DecisionTree decisionTree, ArrayBuilder<BoundStatement> loweredDecisionTree)
{
var oldLoweredDecisionTree = this.LoweredDecisionTree;
this.LoweredDecisionTree = loweredDecisionTree;
var oldLoweredDecisionTree = this._loweredDecisionTree;
this._loweredDecisionTree = loweredDecisionTree;
LowerDecisionTree(expression, decisionTree);
this.LoweredDecisionTree = oldLoweredDecisionTree;
this._loweredDecisionTree = oldLoweredDecisionTree;
}
public void LowerDecisionTree(BoundExpression expression, DecisionTree decisionTree)
private void LowerDecisionTree(BoundExpression expression, DecisionTree decisionTree)
{
if (decisionTree == null) return;
......@@ -96,7 +97,7 @@ public void LowerDecisionTree(BoundExpression expression, DecisionTree decisionT
// Store the input expression into a temp
if (decisionTree.Expression != expression)
{
LoweredDecisionTree.Add(_factory.Assignment(decisionTree.Expression, expression));
_loweredDecisionTree.Add(_factory.Assignment(decisionTree.Expression, expression));
}
if (DeclaredTempSet.Add(decisionTree.Temp))
......@@ -171,10 +172,10 @@ private void LowerDecisionTree(DecisionTree.ByType byType)
BoundExpression notNull = byType.Type.IsNullableType()
? LocalRewriter.RewriteNullableNullEquality(_factory.Syntax, BinaryOperatorKind.NullableNullNotEqual, byType.Expression, nullValue, _factory.SpecialType(SpecialType.System_Boolean))
: _factory.ObjectNotEqual(byType.Expression, nullValue);
LoweredDecisionTree.Add(_factory.ConditionalGoto(notNull, notNullLabel, true));
_loweredDecisionTree.Add(_factory.ConditionalGoto(notNull, notNullLabel, true));
LowerDecisionTree(byType.Expression, byType.WhenNull);
if (byType.WhenNull?.MatchIsComplete != true) LoweredDecisionTree.Add(_factory.Goto(defaultLabel));
LoweredDecisionTree.Add(_factory.Label(notNullLabel));
if (byType.WhenNull?.MatchIsComplete != true) _loweredDecisionTree.Add(_factory.Goto(defaultLabel));
_loweredDecisionTree.Add(_factory.Label(notNullLabel));
}
else
{
......@@ -188,13 +189,13 @@ private void LowerDecisionTree(DecisionTree.ByType byType)
var decision = td.Value;
var failLabel = _factory.GenerateLabel("failedDecision");
var testAndCopy = TypeTestAndCopyToTemp(byType.Expression, decision.Expression);
LoweredDecisionTree.Add(_factory.ConditionalGoto(testAndCopy, failLabel, false));
_loweredDecisionTree.Add(_factory.ConditionalGoto(testAndCopy, failLabel, false));
LowerDecisionTree(decision.Expression, decision);
LoweredDecisionTree.Add(_factory.Label(failLabel));
_loweredDecisionTree.Add(_factory.Label(failLabel));
}
// finally, the default for when no type matches
LoweredDecisionTree.Add(_factory.Label(defaultLabel));
_loweredDecisionTree.Add(_factory.Label(defaultLabel));
LowerDecisionTree(byType.Expression, byType.Default);
}
}
......@@ -219,6 +220,12 @@ private void LowerDecisionTree(DecisionTree.ByValue byValue)
return;
}
if (byValue.ValueAndDecision.Count == 0)
{
LowerDecisionTree(byValue.Expression, byValue.Default);
return;
}
switch (byValue.Type.SpecialType)
{
case SpecialType.System_Byte:
......@@ -268,12 +275,10 @@ private void LowerConstantValueDecision(DecisionTree.ByValue byValue)
if (byValue.ValueAndDecision.TryGetValue(value, out onValue))
{
LowerDecisionTree(byValue.Expression, onValue);
if (!onValue.MatchIsComplete) LowerDecisionTree(byValue.Expression, byValue.Default);
}
else
{
LowerDecisionTree(byValue.Expression, byValue.Default);
if (onValue.MatchIsComplete) return;
}
LowerDecisionTree(byValue.Expression, byValue.Default);
}
private void LowerDecisionTree(DecisionTree.Guarded guarded)
......@@ -286,13 +291,13 @@ private void LowerDecisionTree(DecisionTree.Guarded guarded)
// unconditional
if (guarded.Bindings.IsDefaultOrEmpty)
{
LoweredDecisionTree.Add(_factory.Goto(targetLabel));
_loweredDecisionTree.Add(_factory.Goto(targetLabel));
}
else
{
// with bindings
var matched = _factory.GenerateLabel("matched");
LoweredDecisionTree.Add(_factory.Goto(matched));
_loweredDecisionTree.Add(_factory.Goto(matched));
sectionBuilder.Add(_factory.Label(matched));
AddBindings(sectionBuilder, guarded.Bindings);
sectionBuilder.Add(_factory.Goto(targetLabel));
......@@ -301,13 +306,13 @@ private void LowerDecisionTree(DecisionTree.Guarded guarded)
else
{
var checkGuard = _factory.GenerateLabel("checkGuard");
LoweredDecisionTree.Add(_factory.Goto(checkGuard));
_loweredDecisionTree.Add(_factory.Goto(checkGuard));
sectionBuilder.Add(_factory.Label(checkGuard));
AddBindings(sectionBuilder, guarded.Bindings);
sectionBuilder.Add(_factory.ConditionalGoto(LocalRewriter.VisitExpression(guarded.Guard), targetLabel, true));
var guardFailed = _factory.GenerateLabel("guardFailed");
sectionBuilder.Add(_factory.Goto(guardFailed));
LoweredDecisionTree.Add(_factory.Label(guardFailed));
_loweredDecisionTree.Add(_factory.Label(guardFailed));
}
}
......@@ -382,7 +387,7 @@ private void LowerBasicSwitch(DecisionTree.ByValue byValue)
constantTarget,
ImmutableArray<LocalSymbol>.Empty, ImmutableArray<LocalFunctionSymbol>.Empty,
rewrittenSections, noValueMatches, stringEquality);
LoweredDecisionTree.Add(switchStatement);
_loweredDecisionTree.Add(switchStatement);
// The bound switch statement implicitly defines the label noValueMatches at the end, so we do not add it explicitly.
LowerDecisionTree(byValue.Expression, byValue.Default);
}
......@@ -393,8 +398,8 @@ private void LowerBooleanSwitch(DecisionTree.ByValue byValue)
{
case 0:
{
LowerDecisionTree(byValue.Expression, byValue.Default);
break;
// this should have been handled in the caller.
throw ExceptionUtilities.Unreachable;
}
case 1:
{
......@@ -403,10 +408,10 @@ private void LowerBooleanSwitch(DecisionTree.ByValue byValue)
if (!onBoolean) byValue.ValueAndDecision.TryGetValue(false, out decision);
Debug.Assert(decision != null);
var onOther = _factory.GenerateLabel("on" + !onBoolean);
LoweredDecisionTree.Add(_factory.ConditionalGoto(byValue.Expression, onOther, !onBoolean));
_loweredDecisionTree.Add(_factory.ConditionalGoto(byValue.Expression, onOther, !onBoolean));
LowerDecisionTree(byValue.Expression, decision);
// if we fall through here, that means the match was not complete and we invoke the default part
LoweredDecisionTree.Add(_factory.Label(onOther));
_loweredDecisionTree.Add(_factory.Label(onOther));
LowerDecisionTree(byValue.Expression, byValue.Default);
break;
}
......@@ -418,12 +423,12 @@ private void LowerBooleanSwitch(DecisionTree.ByValue byValue)
Debug.Assert(hasTrue && hasFalse);
var tryAnother = _factory.GenerateLabel("tryAnother");
var onFalse = _factory.GenerateLabel("onFalse");
LoweredDecisionTree.Add(_factory.ConditionalGoto(byValue.Expression, onFalse, false));
_loweredDecisionTree.Add(_factory.ConditionalGoto(byValue.Expression, onFalse, false));
LowerDecisionTree(byValue.Expression, trueDecision);
LoweredDecisionTree.Add(_factory.Goto(tryAnother));
LoweredDecisionTree.Add(_factory.Label(onFalse));
_loweredDecisionTree.Add(_factory.Goto(tryAnother));
_loweredDecisionTree.Add(_factory.Label(onFalse));
LowerDecisionTree(byValue.Expression, falseDecision);
LoweredDecisionTree.Add(_factory.Label(tryAnother));
_loweredDecisionTree.Add(_factory.Label(tryAnother));
// if both true and false (i.e. all values) are fully handled, there should be no default.
Debug.Assert(!trueDecision.MatchIsComplete || !falseDecision.MatchIsComplete || byValue.Default == null);
LowerDecisionTree(byValue.Expression, byValue.Default);
......@@ -440,7 +445,7 @@ private void LowerBooleanSwitch(DecisionTree.ByValue byValue)
/// </summary>
private void LowerOtherSwitch(DecisionTree.ByValue byValue)
{
// PROTOTYPE(typeswitch): we do not yet support switch on float, double, or decimal.
this.LocalRewriter._diagnostics.Add(ErrorCode.ERR_FeatureIsUnimplemented, _factory.Syntax.GetLocation(), "switch on float, double, or decimal");
throw new NotImplementedException();
}
}
......
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