/// <summary>
/// Return value indicates whether all code paths emitted return.
/// </summary>
- public abstract bool Emit (EmitContext ec);
+ protected abstract bool DoEmit (EmitContext ec);
+
+ /// <summary>
+ /// Return value indicates whether all code paths emitted return.
+ /// </summary>
+ public virtual bool Emit (EmitContext ec)
+ {
+ ec.Mark (loc);
+ Report.Debug (8, "MARK", this, loc);
+ return DoEmit (ec);
+ }
public static Expression ResolveBoolean (EmitContext ec, Expression e, Location loc)
{
31, loc, "Can not convert the expression to a boolean");
}
- if (CodeGen.SymbolWriter != null)
- ec.Mark (loc);
+ ec.Mark (loc);
return e;
}
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
return false;
}
public override bool Resolve (EmitContext ec)
{
- Report.Debug (1, "START IF BLOCK");
+ Report.Debug (1, "START IF BLOCK", loc);
expr = ResolveBoolean (ec, expr, loc);
if (expr == null){
ec.EndFlowBranching ();
- Report.Debug (1, "END IF BLOCK");
+ Report.Debug (1, "END IF BLOCK", loc);
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ILGenerator ig = ec.ig;
Label false_target = ig.DefineLabel ();
public class Do : Statement {
public Expression expr;
public readonly Statement EmbeddedStatement;
+ bool infinite, may_return;
public Do (Statement statement, Expression boolExpr, Location l)
{
public override bool Resolve (EmitContext ec)
{
+ bool ok = true;
+
+ ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+
if (!EmbeddedStatement.Resolve (ec))
- return false;
+ ok = false;
expr = ResolveBoolean (ec, expr, loc);
if (expr == null)
- return false;
-
- return true;
+ ok = false;
+ else if (expr is BoolConstant){
+ bool res = ((BoolConstant) expr).Value;
+
+ if (res)
+ infinite = true;
+ }
+
+ ec.CurrentBranching.Infinite = infinite;
+ FlowReturns returns = ec.EndFlowBranching ();
+ may_return = returns != FlowReturns.NEVER;
+
+ return ok;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ILGenerator ig = ec.ig;
Label loop = ig.DefineLabel ();
Label old_begin = ec.LoopBegin;
Label old_end = ec.LoopEnd;
bool old_inloop = ec.InLoop;
- bool old_breaks = ec.Breaks;
int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
ec.LoopBegin = ig.DefineLabel ();
ec.LoopBeginTryCatchLevel = ec.TryCatchLevel;
ig.MarkLabel (loop);
- ec.Breaks = false;
EmbeddedStatement.Emit (ec);
- bool breaks = ec.Breaks;
ig.MarkLabel (ec.LoopBegin);
//
ec.LoopBegin = old_begin;
ec.LoopEnd = old_end;
ec.InLoop = old_inloop;
- ec.Breaks = old_breaks;
-
- //
- // Inform whether we are infinite or not
- //
- if (expr is BoolConstant){
- BoolConstant bc = (BoolConstant) expr;
- if (bc.Value == true)
- return breaks == false;
- }
-
- return false;
+ if (infinite)
+ return may_return == false;
+ else
+ return false;
}
}
public class While : Statement {
public Expression expr;
public readonly Statement Statement;
+ bool may_return, empty, infinite;
public While (Expression boolExpr, Statement statement, Location l)
{
public override bool Resolve (EmitContext ec)
{
+ bool ok = true;
+
expr = ResolveBoolean (ec, expr, loc);
if (expr == null)
return false;
-
- return Statement.Resolve (ec);
+
+ ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+
+ //
+ // Inform whether we are infinite or not
+ //
+ if (expr is BoolConstant){
+ BoolConstant bc = (BoolConstant) expr;
+
+ if (bc.Value == false){
+ Warning_DeadCodeFound (Statement.loc);
+ empty = true;
+ } else
+ infinite = true;
+ } else {
+ //
+ // We are not infinite, so the loop may or may not be executed.
+ //
+ ec.CurrentBranching.CreateSibling ();
+ }
+
+ if (!Statement.Resolve (ec))
+ ok = false;
+
+ if (empty)
+ ec.KillFlowBranching ();
+ else {
+ ec.CurrentBranching.Infinite = infinite;
+ FlowReturns returns = ec.EndFlowBranching ();
+ may_return = returns != FlowReturns.NEVER;
+ }
+
+ return ok;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
+ if (empty)
+ return false;
+
ILGenerator ig = ec.ig;
Label old_begin = ec.LoopBegin;
Label old_end = ec.LoopEnd;
bool old_inloop = ec.InLoop;
- bool old_breaks = ec.Breaks;
- Label while_loop = ig.DefineLabel ();
int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
bool ret;
ec.InLoop = true;
ec.LoopBeginTryCatchLevel = ec.TryCatchLevel;
- ig.Emit (OpCodes.Br, ec.LoopBegin);
- ig.MarkLabel (while_loop);
-
//
// Inform whether we are infinite or not
//
BoolConstant bc = (BoolConstant) expr;
ig.MarkLabel (ec.LoopBegin);
- if (bc.Value == false){
- Warning_DeadCodeFound (Statement.loc);
- ret = false;
- } else {
- bool breaks;
-
- ec.Breaks = false;
- Statement.Emit (ec);
- breaks = ec.Breaks;
- ig.Emit (OpCodes.Br, ec.LoopBegin);
+ Statement.Emit (ec);
+ ig.Emit (OpCodes.Br, ec.LoopBegin);
- //
- // Inform that we are infinite (ie, `we return'), only
- // if we do not `break' inside the code.
- //
- ret = breaks == false;
- }
+ //
+ // Inform that we are infinite (ie, `we return'), only
+ // if we do not `break' inside the code.
+ //
+ ret = may_return == false;
ig.MarkLabel (ec.LoopEnd);
} else {
+ Label while_loop = ig.DefineLabel ();
+
+ ig.Emit (OpCodes.Br, ec.LoopBegin);
+ ig.MarkLabel (while_loop);
+
Statement.Emit (ec);
ig.MarkLabel (ec.LoopBegin);
ec.LoopBegin = old_begin;
ec.LoopEnd = old_end;
ec.InLoop = old_inloop;
- ec.Breaks = old_breaks;
ec.LoopBeginTryCatchLevel = old_loop_begin_try_catch_level;
return ret;
readonly Statement InitStatement;
readonly Statement Increment;
readonly Statement Statement;
+ bool may_return, infinite, empty;
public For (Statement initStatement,
Expression test,
Test = ResolveBoolean (ec, Test, loc);
if (Test == null)
ok = false;
- }
+ else if (Test is BoolConstant){
+ BoolConstant bc = (BoolConstant) Test;
+
+ if (bc.Value == false){
+ Warning_DeadCodeFound (Statement.loc);
+ empty = true;
+ } else
+ infinite = true;
+ }
+ } else
+ infinite = true;
if (Increment != null){
if (!Increment.Resolve (ec))
ok = false;
}
-
- return Statement.Resolve (ec) && ok;
+
+ ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+ if (!infinite)
+ ec.CurrentBranching.CreateSibling ();
+
+ if (!Statement.Resolve (ec))
+ ok = false;
+
+ if (empty)
+ ec.KillFlowBranching ();
+ else {
+ ec.CurrentBranching.Infinite = infinite;
+ FlowReturns returns = ec.EndFlowBranching ();
+ may_return = returns != FlowReturns.NEVER;
+ }
+
+ return ok;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
+ if (empty)
+ return false;
+
ILGenerator ig = ec.ig;
Label old_begin = ec.LoopBegin;
Label old_end = ec.LoopEnd;
bool old_inloop = ec.InLoop;
- bool old_breaks = ec.Breaks;
int old_loop_begin_try_catch_level = ec.LoopBeginTryCatchLevel;
Label loop = ig.DefineLabel ();
Label test = ig.DefineLabel ();
ig.Emit (OpCodes.Br, test);
ig.MarkLabel (loop);
- ec.Breaks = false;
Statement.Emit (ec);
- bool breaks = ec.Breaks;
ig.MarkLabel (ec.LoopBegin);
if (!(Increment is EmptyStatement))
ec.LoopBegin = old_begin;
ec.LoopEnd = old_end;
ec.InLoop = old_inloop;
- ec.Breaks = old_breaks;
ec.LoopBeginTryCatchLevel = old_loop_begin_try_catch_level;
//
- // Inform whether we are infinite or not
+ // Inform whether we are infinite or not
//
if (Test != null){
if (Test is BoolConstant){
BoolConstant bc = (BoolConstant) Test;
if (bc.Value)
- return breaks == false;
+ return may_return == false;
}
return false;
} else
- return true;
+ return may_return == false;
}
}
return expr != null;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ILGenerator ig = ec.ig;
if (ec.CurrentBranching.InTryBlock ())
ec.CurrentBranching.AddFinallyVector (vector);
+ else
+ vector.CheckOutParameters (ec.CurrentBranching);
vector.Returns = FlowReturns.ALWAYS;
vector.Breaks = FlowReturns.ALWAYS;
-
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
if (ec.InFinally){
Report.Error (157,loc,"Control can not leave the body of the finally block");
}
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
Label l = label.LabelTarget (ec);
ec.ig.Emit (OpCodes.Br, l);
{
if (vectors != null)
ec.CurrentBranching.CurrentUsageVector.MergeJumpOrigins (vectors);
+ else {
+ ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.NEVER;
+ ec.CurrentBranching.CurrentUsageVector.Returns = FlowReturns.NEVER;
+ }
referenced = true;
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
LabelTarget (ec);
ec.ig.MarkLabel (label);
public override bool Resolve (EmitContext ec)
{
- ec.CurrentBranching.CurrentUsageVector.Returns = FlowReturns.UNREACHABLE;
- ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
+ ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.UNREACHABLE;
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
if (ec.Switch == null){
Report.Error (153, loc, "goto default is only valid in a switch statement");
label = sl.ILLabelCode;
- ec.CurrentBranching.CurrentUsageVector.Returns = FlowReturns.UNREACHABLE;
- ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
+ ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.UNREACHABLE;
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ec.ig.Emit (OpCodes.Br, label);
return true;
Type t = expr.Type;
- if (t != TypeManager.exception_type && !t.IsSubclassOf (TypeManager.exception_type)) {
+ if ((t != TypeManager.exception_type) &&
+ !t.IsSubclassOf (TypeManager.exception_type) &&
+ !(expr is NullLiteral)) {
Report.Error (155, loc,
"The type caught or thrown must be derived " +
"from System.Exception");
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
if (expr == null){
if (ec.InCatch)
public override bool Resolve (EmitContext ec)
{
+ ec.CurrentBranching.MayLeaveLoop = true;
ec.CurrentBranching.CurrentUsageVector.Breaks = FlowReturns.ALWAYS;
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ILGenerator ig = ec.ig;
return false;
}
- ec.Breaks = true;
if (ec.InTry || ec.InCatch)
ig.Emit (OpCodes.Leave, ec.LoopEnd);
else
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
Label begin = ec.LoopBegin;
// Normal (conditional or toplevel) block.
BLOCK,
+ // A loop block.
+ LOOP_BLOCK,
+
// Try/Catch block.
EXCEPTION,
// </summary>
public ArrayList Siblings;
+ // <summary>
+ // If this is an infinite loop.
+ // </summary>
+ public bool Infinite;
+
+ // <summary>
+ // If we may leave the current loop.
+ // </summary>
+ public bool MayLeaveLoop;
+
//
// Private
//
InternalParameters param_info;
int[] param_map;
+ MyStructInfo[] struct_params;
int num_params;
ArrayList finally_vectors;
//
MyBitVector locals, parameters;
FlowReturns real_returns, real_breaks;
- bool returns_set, breaks_set, is_finally;
+ bool is_finally;
static int next_id = 0;
int id;
locals = new MyBitVector (parent.locals, CountLocals);
if (num_params > 0)
parameters = new MyBitVector (parent.parameters, num_params);
+ real_returns = parent.Returns;
+ real_breaks = parent.Breaks;
} else {
locals = new MyBitVector (null, CountLocals);
if (num_params > 0)
//
// State of the local variable `vi'.
+ // If the local variable is a struct, use a non-zero `field_idx'
+ // to check an individual field in it.
//
- public bool this [VariableInfo vi]
+ public bool this [VariableInfo vi, int field_idx]
{
get {
if (vi.Number == -1)
else if (vi.Number == 0)
throw new ArgumentException ();
- return locals [vi.Number - 1];
+ return locals [vi.Number + field_idx - 1];
}
set {
else if (vi.Number == 0)
throw new ArgumentException ();
- locals [vi.Number - 1] = value;
+ locals [vi.Number + field_idx - 1] = value;
}
}
// <summary>
// Specifies when the current block returns.
+ // If this is FlowReturns.UNREACHABLE, then control can never reach the
+ // end of the method (so that we don't need to emit a return statement).
+ // The same applies for FlowReturns.EXCEPTION, but in this case the return
+ // value will never be used.
// </summary>
public FlowReturns Returns {
get {
set {
real_returns = value;
- returns_set = true;
}
}
// Specifies whether control may return to our containing block
// before reaching the end of this block. This happens if there
// is a break/continue/goto/return in it.
+ // This can also be used to find out whether the statement immediately
+ // following the current block may be reached or not.
// </summary>
public FlowReturns Breaks {
get {
set {
real_breaks = value;
- breaks_set = true;
+ }
+ }
+
+ public bool AlwaysBreaks {
+ get {
+ return (Breaks == FlowReturns.ALWAYS) ||
+ (Breaks == FlowReturns.EXCEPTION) ||
+ (Breaks == FlowReturns.UNREACHABLE);
+ }
+ }
+
+ public bool MayBreak {
+ get {
+ return Breaks != FlowReturns.NEVER;
+ }
+ }
+
+ public bool AlwaysReturns {
+ get {
+ return (Returns == FlowReturns.ALWAYS) ||
+ (Returns == FlowReturns.EXCEPTION);
+ }
+ }
+
+ public bool MayReturn {
+ get {
+ return (Returns == FlowReturns.SOMETIMES) ||
+ (Returns == FlowReturns.ALWAYS);
}
}
FlowReturns new_returns = FlowReturns.NEVER;
FlowReturns new_breaks = FlowReturns.NEVER;
bool new_returns_set = false, new_breaks_set = false;
- FlowReturns breaks;
- Report.Debug (1, "MERGING CHILDREN", branching, this);
+ Report.Debug (2, "MERGING CHILDREN", branching, branching.Type,
+ this, children.Count);
foreach (UsageVector child in children) {
- Report.Debug (1, " MERGING CHILD", child);
-
- // If Returns is already set, perform an `And' operation on it,
- // otherwise just set just.
- if (!new_returns_set) {
- new_returns = child.Returns;
- new_returns_set = true;
- } else
- new_returns = AndFlowReturns (new_returns, child.Returns);
+ Report.Debug (2, " MERGING CHILD", child, child.is_finally);
+
+ if (!child.is_finally) {
+ if (child.Breaks != FlowReturns.UNREACHABLE) {
+ // If Returns is already set, perform an
+ // `And' operation on it, otherwise just set just.
+ if (!new_returns_set) {
+ new_returns = child.Returns;
+ new_returns_set = true;
+ } else
+ new_returns = AndFlowReturns (
+ new_returns, child.Returns);
+ }
- // If Breaks is already set, perform an `And' operation on it,
- // otherwise just set just.
- if (!new_breaks_set) {
- new_breaks = child.Breaks;
- new_breaks_set = true;
- } else
- new_breaks = AndFlowReturns (new_breaks, child.Breaks);
+ // If Breaks is already set, perform an
+ // `And' operation on it, otherwise just set just.
+ if (!new_breaks_set) {
+ new_breaks = child.Breaks;
+ new_breaks_set = true;
+ } else
+ new_breaks = AndFlowReturns (
+ new_breaks, child.Breaks);
+ }
// Ignore unreachable children.
if (child.Returns == FlowReturns.UNREACHABLE)
continue;
- // If we're a switch section, `break' won't leave the current
- // branching (NOTE: the type check here means that we're "a"
- // switch section, not that we're "in" a switch section!).
- breaks = (branching.Type == FlowBranchingType.SWITCH_SECTION) ?
- child.Returns : child.Breaks;
-
// A local variable is initialized after a flow branching if it
// has been initialized in all its branches which do neither
// always return or always throw an exception.
// Here, `a' is initialized in line 3 and we must not look at
// line 5 since it always returns.
//
- if ((breaks != FlowReturns.EXCEPTION) &&
- (breaks != FlowReturns.ALWAYS)) {
- if (new_locals != null)
- new_locals.And (child.locals);
- else {
+ if (child.is_finally) {
+ if (new_locals == null)
+ new_locals = locals.Clone ();
+ new_locals.Or (child.locals);
+
+ if (parameters != null) {
+ if (new_params == null)
+ new_params = parameters.Clone ();
+ new_params.Or (child.parameters);
+ }
+
+ } else {
+ if (!child.AlwaysReturns && !child.AlwaysBreaks) {
+ if (new_locals != null)
+ new_locals.And (child.locals);
+ else {
+ new_locals = locals.Clone ();
+ new_locals.Or (child.locals);
+ }
+ } else if (children.Count == 1) {
new_locals = locals.Clone ();
new_locals.Or (child.locals);
}
- }
- // An `out' parameter must be assigned in all branches which do
- // not always throw an exception.
- if (!child.is_finally && (child.Returns != FlowReturns.EXCEPTION)) {
+ // An `out' parameter must be assigned in all branches which do
+ // not always throw an exception.
if (parameters != null) {
- if (new_params != null)
- new_params.And (child.parameters);
- else {
+ if (child.Breaks != FlowReturns.EXCEPTION) {
+ if (new_params != null)
+ new_params.And (child.parameters);
+ else {
+ new_params = parameters.Clone ();
+ new_params.Or (child.parameters);
+ }
+ } else if (children.Count == 1) {
new_params = parameters.Clone ();
new_params.Or (child.parameters);
}
}
}
-
- // If we always return, check whether all `out' parameters have
- // been assigned.
- if ((child.Returns == FlowReturns.ALWAYS) && (child.parameters != null)) {
- branching.CheckOutParameters (
- child.parameters, branching.Location);
- }
}
- // Set new `Returns' status.
- if (!returns_set) {
- Returns = new_returns;
- returns_set = true;
- } else
- Returns = AndFlowReturns (Returns, new_returns);
+ Returns = new_returns;
+ if ((branching.Type == FlowBranchingType.BLOCK) ||
+ (branching.Type == FlowBranchingType.EXCEPTION) ||
+ (new_breaks == FlowReturns.UNREACHABLE) ||
+ (new_breaks == FlowReturns.EXCEPTION))
+ Breaks = new_breaks;
+ else if (branching.Type == FlowBranchingType.SWITCH_SECTION)
+ Breaks = new_returns;
+ else if (branching.Type == FlowBranchingType.SWITCH){
+ if (new_breaks == FlowReturns.ALWAYS)
+ Breaks = FlowReturns.ALWAYS;
+ }
//
// We've now either reached the point after the branching or we will
// we need to look at (see above).
//
- breaks = (branching.Type == FlowBranchingType.SWITCH_SECTION) ?
- Returns : Breaks;
+ if (((new_breaks != FlowReturns.ALWAYS) &&
+ (new_breaks != FlowReturns.EXCEPTION) &&
+ (new_breaks != FlowReturns.UNREACHABLE)) ||
+ (children.Count == 1)) {
+ if (new_locals != null)
+ locals.Or (new_locals);
- if ((new_locals != null) &&
- ((breaks == FlowReturns.NEVER) || (breaks == FlowReturns.SOMETIMES))) {
- locals.Or (new_locals);
+ if (new_params != null)
+ parameters.Or (new_params);
}
- if ((new_params != null) && (Breaks == FlowReturns.NEVER))
- parameters.Or (new_params);
+ Report.Debug (2, "MERGING CHILDREN DONE", branching.Type,
+ new_params, new_locals, new_returns, new_breaks,
+ branching.Infinite, branching.MayLeaveLoop, this);
+
+ if (branching.Type == FlowBranchingType.SWITCH_SECTION) {
+ if ((new_breaks != FlowReturns.ALWAYS) &&
+ (new_breaks != FlowReturns.EXCEPTION) &&
+ (new_breaks != FlowReturns.UNREACHABLE))
+ Report.Error (163, branching.Location,
+ "Control cannot fall through from one " +
+ "case label to another");
+ }
- //
- // If we may have returned (this only happens if there was a reachable
- // `return' statement in one of the branches), then we may return to our
- // parent block before reaching the end of the block, so set `Breaks'.
- //
+ if (branching.Infinite && !branching.MayLeaveLoop) {
+ Report.Debug (1, "INFINITE", new_returns, new_breaks,
+ Returns, Breaks, this);
- if ((Returns != FlowReturns.NEVER) && (Returns != FlowReturns.SOMETIMES)) {
- real_breaks = Returns;
- breaks_set = true;
- }
+ // We're actually infinite.
+ if (new_returns == FlowReturns.NEVER) {
+ Breaks = FlowReturns.UNREACHABLE;
+ return FlowReturns.UNREACHABLE;
+ }
- Report.Debug (1, "MERGING CHILDREN DONE", new_params, new_locals,
- new_returns, new_breaks, this);
+ // If we're an infinite loop and do not break, the code after
+ // the loop can never be reached. However, if we may return
+ // from the loop, then we do always return (or stay in the loop
+ // forever).
+ if ((new_returns == FlowReturns.SOMETIMES) ||
+ (new_returns == FlowReturns.ALWAYS)) {
+ Returns = FlowReturns.ALWAYS;
+ return FlowReturns.ALWAYS;
+ }
+ }
return new_returns;
}
Report.Debug (1, "MERGING JUMP ORIGIN", this);
real_breaks = FlowReturns.NEVER;
- breaks_set = false;
+ real_returns = FlowReturns.NEVER;
foreach (UsageVector vector in origin_vectors) {
Report.Debug (1, " MERGING JUMP ORIGIN", vector);
if (parameters != null)
parameters.And (vector.parameters);
Breaks = AndFlowReturns (Breaks, vector.Breaks);
+ Returns = AndFlowReturns (Returns, vector.Returns);
}
Report.Debug (1, "MERGING JUMP ORIGIN DONE", this);
Report.Debug (1, "MERGING FINALLY ORIGIN", this);
real_breaks = FlowReturns.NEVER;
- breaks_set = false;
foreach (UsageVector vector in finally_vectors) {
Report.Debug (1, " MERGING FINALLY ORIGIN", vector);
Report.Debug (1, "MERGING FINALLY ORIGIN DONE", this);
}
+ public void CheckOutParameters (FlowBranching branching)
+ {
+ if (parameters != null)
+ branching.CheckOutParameters (parameters, branching.Location);
+ }
+
// <summary>
// Performs an `or' operation on the locals and the parameters.
// </summary>
Block = block;
Parent = null;
+ int count = (ip != null) ? ip.Count : 0;
+
param_info = ip;
- param_map = new int [(param_info != null) ? param_info.Count : 0];
+ param_map = new int [count];
+ struct_params = new MyStructInfo [count];
num_params = 0;
- for (int i = 0; i < param_map.Length; i++) {
+ for (int i = 0; i < count; i++) {
Parameter.Modifier mod = param_info.ParameterModifier (i);
if ((mod & Parameter.Modifier.OUT) == 0)
continue;
param_map [i] = ++num_params;
+
+ Type param_type = param_info.ParameterType (i);
+
+ struct_params [i] = MyStructInfo.GetStructInfo (param_type);
+ if (struct_params [i] != null)
+ num_params += struct_params [i].Count;
}
Siblings = new ArrayList ();
if (parent != null) {
param_info = parent.param_info;
param_map = parent.param_map;
+ struct_params = parent.struct_params;
num_params = parent.num_params;
}
return;
for (int i = 0; i < param_map.Length; i++) {
- if (param_map [i] == 0)
+ int index = param_map [i];
+
+ if (index == 0)
+ continue;
+
+ if (parameters [index - 1])
continue;
- if (!parameters [param_map [i] - 1]) {
+ // If it's a struct, we must ensure that all its fields have
+ // been assigned. If the struct has any non-public fields, this
+ // can only be done by assigning the whole struct.
+
+ MyStructInfo struct_info = struct_params [index - 1];
+ if ((struct_info == null) || struct_info.HasNonPublicFields) {
Report.Error (
177, loc, "The out parameter `" +
- param_info.ParameterName (i) + "` must be " +
+ param_info.ParameterName (i) + "' must be " +
"assigned before control leave the current method.");
param_map [i] = 0;
+ continue;
+ }
+
+
+ for (int j = 0; j < struct_info.Count; j++) {
+ if (!parameters [index + j]) {
+ Report.Error (
+ 177, loc, "The out parameter `" +
+ param_info.ParameterName (i) + "' must be " +
+ "assigned before control leave the current method.");
+ param_map [i] = 0;
+ break;
+ }
}
}
}
// </summary>
public FlowReturns MergeChild (FlowBranching child)
{
- return CurrentUsageVector.MergeChildren (child, child.Siblings);
- }
+ FlowReturns returns = CurrentUsageVector.MergeChildren (child, child.Siblings);
+
+ if (child.Type != FlowBranchingType.LOOP_BLOCK)
+ MayLeaveLoop |= child.MayLeaveLoop;
+ else
+ MayLeaveLoop = false;
+ return returns;
+ }
+
// <summary>
// Does the toplevel merging.
// </summary>
UsageVector vector = new UsageVector (null, num_params, Block.CountVariables);
+ Report.Debug (1, "MERGING TOP BLOCK", Location, vector);
+
vector.MergeChildren (this, Siblings);
Siblings.Clear ();
Siblings.Add (vector);
- Report.Debug (1, "MERGING TOP BLOCK", vector);
-
- if (vector.Returns != FlowReturns.EXCEPTION)
- CheckOutParameters (CurrentUsageVector.Parameters, Location);
+ Report.Debug (1, "MERGING TOP BLOCK DONE", Location, vector);
- return vector.Returns;
+ if (vector.Breaks != FlowReturns.EXCEPTION) {
+ if (!vector.AlwaysBreaks)
+ CheckOutParameters (CurrentUsageVector.Parameters, Location);
+ return vector.AlwaysBreaks ? FlowReturns.ALWAYS : vector.Returns;
+ } else
+ return FlowReturns.EXCEPTION;
}
public bool InTryBlock ()
public bool IsVariableAssigned (VariableInfo vi)
{
- Report.Debug (2, "CHECK VARIABLE ACCESS", this, vi);
+ if (CurrentUsageVector.AlwaysBreaks)
+ return true;
+ else
+ return CurrentUsageVector [vi, 0];
+ }
- if (CurrentUsageVector.Breaks == FlowReturns.UNREACHABLE)
+ public bool IsVariableAssigned (VariableInfo vi, int field_idx)
+ {
+ if (CurrentUsageVector.AlwaysBreaks)
return true;
else
- return CurrentUsageVector [vi];
+ return CurrentUsageVector [vi, field_idx];
}
public void SetVariableAssigned (VariableInfo vi)
{
- Report.Debug (2, "SET VARIABLE ACCESS", this, vi, CurrentUsageVector);
+ if (CurrentUsageVector.AlwaysBreaks)
+ return;
- if (CurrentUsageVector.Breaks == FlowReturns.UNREACHABLE)
+ CurrentUsageVector [vi, 0] = true;
+ }
+
+ public void SetVariableAssigned (VariableInfo vi, int field_idx)
+ {
+ if (CurrentUsageVector.AlwaysBreaks)
return;
- CurrentUsageVector [vi] = true;
+ CurrentUsageVector [vi, field_idx] = true;
}
public bool IsParameterAssigned (int number)
{
- Report.Debug (2, "IS PARAMETER ASSIGNED", this, number);
+ int index = param_map [number];
- if (param_map [number] == 0)
+ if (index == 0)
return true;
- else
- return CurrentUsageVector [param_map [number]];
+
+ if (CurrentUsageVector [index])
+ return true;
+
+ // Parameter is not assigned, so check whether it's a struct.
+ // If it's either not a struct or a struct which non-public
+ // fields, return false.
+ MyStructInfo struct_info = struct_params [number];
+ if ((struct_info == null) || struct_info.HasNonPublicFields)
+ return false;
+
+ // Ok, so each field must be assigned.
+ for (int i = 0; i < struct_info.Count; i++)
+ if (!CurrentUsageVector [index + i])
+ return false;
+
+ return true;
}
- public void SetParameterAssigned (int number)
+ public bool IsParameterAssigned (int number, string field_name)
{
- Report.Debug (2, "SET PARAMETER ACCESS", this, number, param_map [number],
- CurrentUsageVector);
+ int index = param_map [number];
+
+ if (index == 0)
+ return true;
+
+ MyStructInfo info = (MyStructInfo) struct_params [number];
+ if (info == null)
+ return true;
+
+ int field_idx = info [field_name];
+
+ return CurrentUsageVector [index + field_idx];
+ }
+ public void SetParameterAssigned (int number)
+ {
if (param_map [number] == 0)
return;
- if (CurrentUsageVector.Breaks == FlowReturns.NEVER)
+ if (!CurrentUsageVector.AlwaysBreaks)
CurrentUsageVector [param_map [number]] = true;
}
+ public void SetParameterAssigned (int number, string field_name)
+ {
+ int index = param_map [number];
+
+ if (index == 0)
+ return;
+
+ MyStructInfo info = (MyStructInfo) struct_params [number];
+ if (info == null)
+ return;
+
+ int field_idx = info [field_name];
+
+ if (!CurrentUsageVector.AlwaysBreaks)
+ CurrentUsageVector [index + field_idx] = true;
+ }
+
+ public bool IsReachable ()
+ {
+ bool reachable;
+
+ switch (Type) {
+ case FlowBranchingType.SWITCH_SECTION:
+ // The code following a switch block is reachable unless the switch
+ // block always returns.
+ reachable = !CurrentUsageVector.AlwaysReturns;
+ break;
+
+ case FlowBranchingType.LOOP_BLOCK:
+ // The code following a loop is reachable unless the loop always
+ // returns or it's an infinite loop without any `break's in it.
+ reachable = !CurrentUsageVector.AlwaysReturns &&
+ (CurrentUsageVector.Breaks != FlowReturns.UNREACHABLE);
+ break;
+
+ default:
+ // The code following a block or exception is reachable unless the
+ // block either always returns or always breaks.
+ reachable = !CurrentUsageVector.AlwaysBreaks &&
+ !CurrentUsageVector.AlwaysReturns;
+ break;
+ }
+
+ Report.Debug (1, "REACHABLE", Type, CurrentUsageVector.Returns,
+ CurrentUsageVector.Breaks, CurrentUsageVector, reachable);
+
+ return reachable;
+ }
+
public override string ToString ()
{
StringBuilder sb = new StringBuilder ("FlowBranching (");
return sb.ToString ();
}
}
+
+ public class MyStructInfo {
+ public readonly Type Type;
+ public readonly FieldInfo[] Fields;
+ public readonly FieldInfo[] NonPublicFields;
+ public readonly int Count;
+ public readonly int CountNonPublic;
+ public readonly bool HasNonPublicFields;
+
+ private static Hashtable field_type_hash = new Hashtable ();
+ private Hashtable field_hash;
+
+ // Private constructor. To save memory usage, we only need to create one instance
+ // of this class per struct type.
+ private MyStructInfo (Type type)
+ {
+ this.Type = type;
+
+ if (type is TypeBuilder) {
+ TypeContainer tc = TypeManager.LookupTypeContainer (type);
+
+ ArrayList fields = tc.Fields;
+ if (fields != null) {
+ foreach (Field field in fields) {
+ if ((field.ModFlags & Modifiers.STATIC) != 0)
+ continue;
+ if ((field.ModFlags & Modifiers.PUBLIC) != 0)
+ ++Count;
+ else
+ ++CountNonPublic;
+ }
+ }
+
+ Fields = new FieldInfo [Count];
+ NonPublicFields = new FieldInfo [CountNonPublic];
+
+ Count = CountNonPublic = 0;
+ if (fields != null) {
+ foreach (Field field in fields) {
+ if ((field.ModFlags & Modifiers.STATIC) != 0)
+ continue;
+ if ((field.ModFlags & Modifiers.PUBLIC) != 0)
+ Fields [Count++] = field.FieldBuilder;
+ else
+ NonPublicFields [CountNonPublic++] =
+ field.FieldBuilder;
+ }
+ }
+
+ } else {
+ Fields = type.GetFields (BindingFlags.Instance|BindingFlags.Public);
+ Count = Fields.Length;
+
+ NonPublicFields = type.GetFields (BindingFlags.Instance|BindingFlags.NonPublic);
+ CountNonPublic = NonPublicFields.Length;
+ }
+
+ Count += NonPublicFields.Length;
+
+ int number = 0;
+ field_hash = new Hashtable ();
+ foreach (FieldInfo field in Fields)
+ field_hash.Add (field.Name, ++number);
+
+ if (NonPublicFields.Length != 0)
+ HasNonPublicFields = true;
+
+ foreach (FieldInfo field in NonPublicFields)
+ field_hash.Add (field.Name, ++number);
+ }
+
+ public int this [string name] {
+ get {
+ if (field_hash.Contains (name))
+ return (int) field_hash [name];
+ else
+ return 0;
+ }
+ }
+
+ public FieldInfo this [int index] {
+ get {
+ if (index >= Fields.Length)
+ return NonPublicFields [index - Fields.Length];
+ else
+ return Fields [index];
+ }
+ }
+
+ public static MyStructInfo GetStructInfo (Type type)
+ {
+ if (!TypeManager.IsValueType (type) || TypeManager.IsEnumType (type))
+ return null;
+
+ if (!(type is TypeBuilder) && TypeManager.IsBuiltinType (type))
+ return null;
+
+ MyStructInfo info = (MyStructInfo) field_type_hash [type];
+ if (info != null)
+ return info;
+
+ info = new MyStructInfo (type);
+ field_type_hash.Add (type, info);
+ return info;
+ }
+
+ public static MyStructInfo GetStructInfo (TypeContainer tc)
+ {
+ MyStructInfo info = (MyStructInfo) field_type_hash [tc.TypeBuilder];
+ if (info != null)
+ return info;
+
+ info = new MyStructInfo (tc.TypeBuilder);
+ field_type_hash.Add (tc.TypeBuilder, info);
+ return info;
+ }
+ }
- public class VariableInfo {
+ public class VariableInfo : IVariable {
public Expression Type;
public LocalBuilder LocalBuilder;
public Type VariableType;
+ public readonly string Name;
public readonly Location Location;
public readonly int Block;
public bool Assigned;
public bool ReadOnly;
- public VariableInfo (Expression type, int block, Location l)
+ public VariableInfo (Expression type, string name, int block, Location l)
{
Type = type;
+ Name = name;
Block = block;
LocalBuilder = null;
Location = l;
}
+ public VariableInfo (TypeContainer tc, int block, Location l)
+ {
+ VariableType = tc.TypeBuilder;
+ struct_info = MyStructInfo.GetStructInfo (tc);
+ Block = block;
+ LocalBuilder = null;
+ Location = l;
+ }
+
+ MyStructInfo struct_info;
+ public MyStructInfo StructInfo {
+ get {
+ return struct_info;
+ }
+ }
+
+ public bool IsAssigned (EmitContext ec, Location loc)
+ {
+ if (!ec.DoFlowAnalysis || ec.CurrentBranching.IsVariableAssigned (this))
+ return true;
+
+ MyStructInfo struct_info = StructInfo;
+ if ((struct_info == null) || (struct_info.HasNonPublicFields && (Name != null))) {
+ Report.Error (165, loc, "Use of unassigned local variable `" + Name + "'");
+ ec.CurrentBranching.SetVariableAssigned (this);
+ return false;
+ }
+
+ int count = struct_info.Count;
+
+ for (int i = 0; i < count; i++) {
+ if (!ec.CurrentBranching.IsVariableAssigned (this, i+1)) {
+ if (Name != null) {
+ Report.Error (165, loc,
+ "Use of unassigned local variable `" +
+ Name + "'");
+ ec.CurrentBranching.SetVariableAssigned (this);
+ return false;
+ }
+
+ FieldInfo field = struct_info [i];
+ Report.Error (171, loc,
+ "Field `" + TypeManager.CSharpName (VariableType) +
+ "." + field.Name + "' must be fully initialized " +
+ "before control leaves the constructor");
+ return false;
+ }
+ }
+
+ return true;
+ }
+
+ public bool IsFieldAssigned (EmitContext ec, string name, Location loc)
+ {
+ if (!ec.DoFlowAnalysis || ec.CurrentBranching.IsVariableAssigned (this) ||
+ (struct_info == null))
+ return true;
+
+ int field_idx = StructInfo [name];
+ if (field_idx == 0)
+ return true;
+
+ if (!ec.CurrentBranching.IsVariableAssigned (this, field_idx)) {
+ Report.Error (170, loc,
+ "Use of possibly unassigned field `" + name + "'");
+ ec.CurrentBranching.SetVariableAssigned (this, field_idx);
+ return false;
+ }
+
+ return true;
+ }
+
+ public void SetAssigned (EmitContext ec)
+ {
+ if (ec.DoFlowAnalysis)
+ ec.CurrentBranching.SetVariableAssigned (this);
+ }
+
+ public void SetFieldAssigned (EmitContext ec, string name)
+ {
+ if (ec.DoFlowAnalysis && (struct_info != null))
+ ec.CurrentBranching.SetVariableAssigned (this, StructInfo [name]);
+ }
+
+ public bool Resolve (DeclSpace decl)
+ {
+ if (struct_info != null)
+ return true;
+
+ if (VariableType == null)
+ VariableType = decl.ResolveType (Type, false, Location);
+
+ if (VariableType == null)
+ return false;
+
+ struct_info = MyStructInfo.GetStructInfo (VariableType);
+
+ return true;
+ }
+
public void MakePinned ()
{
TypeManager.MakePinned (LocalBuilder);
public int ID {
get {
- if (Implicit)
- return Parent.ID;
- else
- return this_id;
+ return this_id;
}
}
-
+
void AddChild (Block b)
{
if (children == null)
return null;
}
+ VariableInfo this_variable = null;
+
+ // <summary>
+ // Returns the "this" instance variable of this block.
+ // See AddThisVariable() for more information.
+ // </summary>
+ public VariableInfo ThisVariable {
+ get {
+ if (this_variable != null)
+ return this_variable;
+ else if (Parent != null)
+ return Parent.ThisVariable;
+ else
+ return null;
+ }
+ }
+
+ Hashtable child_variable_names;
+
+ // <summary>
+ // Marks a variable with name @name as being used in a child block.
+ // If a variable name has been used in a child block, it's illegal to
+ // declare a variable with the same name in the current block.
+ // </summary>
+ public void AddChildVariableName (string name)
+ {
+ if (child_variable_names == null)
+ child_variable_names = new Hashtable ();
+
+ if (!child_variable_names.Contains (name))
+ child_variable_names.Add (name, true);
+ }
+
+ // <summary>
+ // Marks all variables from block @block and all its children as being
+ // used in a child block.
+ // </summary>
+ public void AddChildVariableNames (Block block)
+ {
+ if (block.Variables != null) {
+ foreach (string name in block.Variables.Keys)
+ AddChildVariableName (name);
+ }
+
+ foreach (Block child in block.children) {
+ if (child.Variables != null) {
+ foreach (string name in child.Variables.Keys)
+ AddChildVariableName (name);
+ }
+ }
+ }
+
+ // <summary>
+ // Checks whether a variable name has already been used in a child block.
+ // </summary>
+ public bool IsVariableNameUsedInChildBlock (string name)
+ {
+ if (child_variable_names == null)
+ return false;
+
+ return child_variable_names.Contains (name);
+ }
+
+ // <summary>
+ // This is used by non-static `struct' constructors which do not have an
+ // initializer - in this case, the constructor must initialize all of the
+ // struct's fields. To do this, we add a "this" variable and use the flow
+ // analysis code to ensure that it's been fully initialized before control
+ // leaves the constructor.
+ // </summary>
+ public VariableInfo AddThisVariable (TypeContainer tc, Location l)
+ {
+ if (this_variable != null)
+ return this_variable;
+
+ this_variable = new VariableInfo (tc, ID, l);
+
+ if (variables == null)
+ variables = new Hashtable ();
+ variables.Add ("this", this_variable);
+
+ return this_variable;
+ }
+
public VariableInfo AddVariable (Expression type, string name, Parameters pars, Location l)
{
if (variables == null)
return null;
}
+ if (IsVariableNameUsedInChildBlock (name)) {
+ Report.Error (136, l, "A local variable named `" + name + "' " +
+ "cannot be declared in this scope since it would " +
+ "give a different meaning to `" + name + "', which " +
+ "is already used in a `child' scope to denote something " +
+ "else");
+ return null;
+ }
+
if (pars != null) {
int idx = 0;
Parameter p = pars.GetParameterByName (name, out idx);
}
}
- vi = new VariableInfo (type, ID, l);
+ vi = new VariableInfo (type, name, ID, l);
variables.Add (name, vi);
return null;
}
- /// <summary>
- /// True if the variable named @name has been defined
- /// in this block
- /// </summary>
- public bool IsVariableDefined (string name)
- {
- // Console.WriteLine ("Looking up {0} in {1}", name, ID);
- if (variables != null) {
- if (variables.Contains (name))
- return true;
- }
-
- if (Parent != null)
- return Parent.IsVariableDefined (name);
-
- return false;
- }
-
/// <summary>
/// True if the variable named @name is a constant
/// </summary>
count_variables = first_variable;
if (variables != null) {
foreach (VariableInfo vi in variables.Values) {
- Report.Debug (2, "VARIABLE", vi);
-
- Type type = ds.ResolveType (vi.Type, false, vi.Location);
- if (type == null) {
+ if (!vi.Resolve (ds)) {
vi.Number = -1;
continue;
}
- vi.VariableType = type;
-
- Report.Debug (2, "VARIABLE", vi, type, type.IsValueType,
- TypeManager.IsValueType (type),
- TypeManager.IsBuiltinType (type));
+ vi.Number = ++count_variables;
- // FIXME: we don't have support for structs yet.
- if (TypeManager.IsValueType (type) && !TypeManager.IsBuiltinType (type))
- vi.Number = -1;
- else
- vi.Number = ++count_variables;
+ if (vi.StructInfo != null)
+ count_variables += vi.StructInfo.Count;
}
}
b.UsageWarning ();
}
+ bool has_ret = false;
+
public override bool Resolve (EmitContext ec)
{
Block prev_block = ec.CurrentBlock;
ec.CurrentBlock = this;
ec.StartFlowBranching (this);
- Report.Debug (1, "RESOLVE BLOCK", StartLocation);
+ Report.Debug (1, "RESOLVE BLOCK", StartLocation, ec.CurrentBranching);
if (!variables_initialized)
UpdateVariableInfo (ec);
- foreach (Statement s in statements){
- if (s.Resolve (ec) == false)
- ok = false;
+ ArrayList new_statements = new ArrayList ();
+ bool unreachable = false, warning_shown = false;
+
+ foreach (Statement s in statements){
+ if (unreachable && !(s is LabeledStatement)) {
+ if (!warning_shown && !(s is EmptyStatement)) {
+ warning_shown = true;
+ Warning_DeadCodeFound (s.loc);
+ }
+
+ continue;
+ }
+
+ if (s.Resolve (ec) == false) {
+ ok = false;
+ continue;
+ }
+
+ if (s is LabeledStatement)
+ unreachable = false;
+ else
+ unreachable = ! ec.CurrentBranching.IsReachable ();
+
+ new_statements.Add (s);
}
- Report.Debug (1, "RESOLVE BLOCK DONE", StartLocation);
+ statements = new_statements;
- ec.EndFlowBranching ();
+ Report.Debug (1, "RESOLVE BLOCK DONE", StartLocation, ec.CurrentBranching);
+
+ FlowReturns returns = ec.EndFlowBranching ();
ec.CurrentBlock = prev_block;
+ // If we're a non-static `struct' constructor which doesn't have an
+ // initializer, then we must initialize all of the struct's fields.
+ if ((this_variable != null) && (returns != FlowReturns.EXCEPTION) &&
+ !this_variable.IsAssigned (ec, loc))
+ ok = false;
+
if ((labels != null) && (RootContext.WarningLevel >= 2)) {
foreach (LabeledStatement label in labels.Values)
if (!label.HasBeenReferenced)
"This label has not been referenced");
}
+ if ((returns == FlowReturns.ALWAYS) ||
+ (returns == FlowReturns.EXCEPTION) ||
+ (returns == FlowReturns.UNREACHABLE))
+ has_ret = true;
+
return ok;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
- bool is_ret = false, this_ret = false;
Block prev_block = ec.CurrentBlock;
- bool warning_shown = false;
ec.CurrentBlock = this;
- if (CodeGen.SymbolWriter != null) {
- ec.Mark (StartLocation);
-
- foreach (Statement s in statements) {
- ec.Mark (s.loc);
-
- if (is_ret && !warning_shown && !(s is EmptyStatement)){
- warning_shown = true;
- Warning_DeadCodeFound (s.loc);
- }
- this_ret = s.Emit (ec);
- if (this_ret)
- is_ret = true;
- }
-
- ec.Mark (EndLocation);
- } else {
- foreach (Statement s in statements){
- if (is_ret && !warning_shown && !(s is EmptyStatement)){
- warning_shown = true;
- Warning_DeadCodeFound (s.loc);
- }
- this_ret = s.Emit (ec);
- if (this_ret)
- is_ret = true;
- }
- }
+ ec.Mark (StartLocation);
+ foreach (Statement s in statements)
+ s.Emit (ec);
+ ec.Mark (EndLocation);
ec.CurrentBlock = prev_block;
- return is_ret;
+ return has_ret;
}
}
if (e is StringConstant || e is NullLiteral){
if (required_type == TypeManager.string_type){
- converted = label;
+ converted = e;
ILLabel = ec.ig.DefineLabel ();
return true;
}
fFoundDefault = true;
}
}
- fAllReturn &= ss.Block.Emit (ec);
+ bool returns = ss.Block.Emit (ec);
+ fAllReturn &= returns;
//ig.Emit (OpCodes.Br, lblEnd);
}
ig.Emit (OpCodes.Call, TypeManager.string_isinterneted_string);
ig.Emit (OpCodes.Stloc, val);
}
-
- SwitchSection last_section;
- last_section = (SwitchSection) Sections [Sections.Count-1];
foreach (SwitchSection ss in Sections){
Label sec_begin = ig.DefineLabel ();
}
}
}
- if (label_count != 1 && ss != last_section)
+ if (label_count != 1)
ig.Emit (OpCodes.Br, next_test);
if (null_found)
ig.MarkLabel (null_target);
ig.MarkLabel (sec_begin);
- foreach (SwitchLabel sl in ss.Labels)\r
+ foreach (SwitchLabel sl in ss.Labels)
ig.MarkLabel (sl.ILLabelCode);
- if (ss.Block.Emit (ec))
+
+ bool returns = ss.Block.Emit (ec);
+ if (returns)
pending_goto_end = false;
else {
all_return = false;
return false;
}
+
+ if (!got_default)
+ ec.CurrentBranching.CreateSibling ();
+
ec.EndFlowBranching ();
ec.Switch = old_switch;
return true;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
// Store variable for comparission purposes
LocalBuilder value = ec.ig.DeclareLocal (SwitchType);
return Statement.Resolve (ec) && expr != null;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
Type type = expr.Type;
bool val;
return Block.Resolve (ec);
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
bool previous_state = ec.CheckState;
bool previous_state_const = ec.ConstantCheckState;
return ret;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
bool previous_state = ec.CheckState;
bool previous_state_const = ec.ConstantCheckState;
return val;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
bool previous_state = ec.InUnsafe;
bool val;
return statement.Resolve (ec);
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ILGenerator ig = ec.ig;
public readonly Block Block;
public readonly Location Location;
- Expression type;
+ Expression type_expr;
+ Type type;
public Catch (Expression type, string name, Block block, Location l)
{
- this.type = type;
+ type_expr = type;
Name = name;
Block = block;
Location = l;
public Type CatchType {
get {
- if (type == null)
- throw new InvalidOperationException ();
-
- return type.Type;
+ return type;
}
}
public bool IsGeneral {
get {
- return type == null;
+ return type_expr == null;
}
}
public bool Resolve (EmitContext ec)
{
- if (type != null) {
- type = type.DoResolve (ec);
+ if (type_expr != null) {
+ type = ec.DeclSpace.ResolveType (type_expr, false, Location);
if (type == null)
return false;
- Type t = type.Type;
- if (t != TypeManager.exception_type && !t.IsSubclassOf (TypeManager.exception_type)){
+ if (type != TypeManager.exception_type && !type.IsSubclassOf (TypeManager.exception_type)){
Report.Error (155, Location,
"The type caught or thrown must be derived " +
"from System.Exception");
return false;
}
- }
+ } else
+ type = null;
if (!Block.Resolve (ec))
return false;
FlowBranching.UsageVector current = ec.CurrentBranching.CurrentUsageVector;
- if ((current.Returns == FlowReturns.NEVER) ||
- (current.Returns == FlowReturns.SOMETIMES)) {
+ if (!current.AlwaysReturns && !current.AlwaysBreaks)
vector.AndLocals (current);
- }
}
+ Report.Debug (1, "END OF CATCH BLOCKS", ec.CurrentBranching);
+
if (General != null){
ec.CurrentBranching.CreateSibling ();
Report.Debug (1, "STARTED SIBLING FOR GENERAL", ec.CurrentBranching);
FlowBranching.UsageVector current = ec.CurrentBranching.CurrentUsageVector;
- if ((current.Returns == FlowReturns.NEVER) ||
- (current.Returns == FlowReturns.SOMETIMES)) {
+ if (!current.AlwaysReturns && !current.AlwaysBreaks)
vector.AndLocals (current);
- }
}
- ec.CurrentBranching.CreateSiblingForFinally ();
- Report.Debug (1, "STARTED SIBLING FOR FINALLY", ec.CurrentBranching, vector);
+ Report.Debug (1, "END OF GENERAL CATCH BLOCKS", ec.CurrentBranching);
if (Fini != null) {
+ ec.CurrentBranching.CreateSiblingForFinally ();
+ Report.Debug (1, "STARTED SIBLING FOR FINALLY", ec.CurrentBranching, vector);
+
bool old_in_finally = ec.InFinally;
ec.InFinally = true;
ec.InFinally = old_in_finally;
}
- FlowBranching.UsageVector f_vector = ec.CurrentBranching.CurrentUsageVector;
-
FlowReturns returns = ec.EndFlowBranching ();
+ FlowBranching.UsageVector f_vector = ec.CurrentBranching.CurrentUsageVector;
+
Report.Debug (1, "END OF FINALLY", ec.CurrentBranching, returns, vector, f_vector);
if ((returns == FlowReturns.SOMETIMES) || (returns == FlowReturns.ALWAYS)) {
return ok;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
ILGenerator ig = ec.ig;
Label end;
}
}
- //
- // FIXME: We still do not support the expression variant of the using
- // statement.
- //
public class Using : Statement {
object expression_or_block;
Statement Statement;
if (var == null)
return false;
- converted_vars [i] = Expression.ConvertImplicit (
+ converted_vars [i] = Expression.ConvertImplicitRequired (
ec, var, TypeManager.idisposable_type, loc);
if (converted_vars [i] == null)
bool ResolveExpression (EmitContext ec)
{
if (!TypeManager.ImplementsInterface (expr_type, TypeManager.idisposable_type)){
- conv = Expression.ConvertImplicit (
+ conv = Expression.ConvertImplicitRequired (
ec, expr, TypeManager.idisposable_type, loc);
if (conv == null)
return Statement.Resolve (ec);
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
if (expression_or_block is DictionaryEntry)
return EmitLocalVariableDecls (ec);
// out to return values in ExprClass? I think they should.
//
if (!(expr.eclass == ExprClass.Variable || expr.eclass == ExprClass.Value ||
- expr.eclass == ExprClass.PropertyAccess)){
+ expr.eclass == ExprClass.PropertyAccess || expr.eclass == ExprClass.IndexerAccess)){
error1579 (expr.Type);
return false;
}
empty = new EmptyExpression (hm.element_type);
}
+ ec.StartFlowBranching (FlowBranchingType.LOOP_BLOCK, loc);
+ ec.CurrentBranching.CreateSibling ();
+
+ //
//
// FIXME: maybe we can apply the same trick we do in the
// array handling to avoid creating empty and conv in some cases.
if (!statement.Resolve (ec))
return false;
+ FlowReturns returns = ec.EndFlowBranching ();
+
return true;
}
//
static MethodInfo FetchMethodMoveNext (Type t)
{
- MemberInfo [] move_next_list;
+ MemberList move_next_list;
move_next_list = TypeContainer.FindMembers (
t, MemberTypes.Method,
BindingFlags.Public | BindingFlags.Instance,
Type.FilterName, "MoveNext");
- if (move_next_list == null || move_next_list.Length == 0)
+ if (move_next_list.Count == 0)
return null;
foreach (MemberInfo m in move_next_list){
//
static MethodInfo FetchMethodGetCurrent (Type t)
{
- MemberInfo [] move_next_list;
+ MemberList move_next_list;
move_next_list = TypeContainer.FindMembers (
t, MemberTypes.Method,
BindingFlags.Public | BindingFlags.Instance,
Type.FilterName, "get_Current");
- if (move_next_list == null || move_next_list.Length == 0)
+ if (move_next_list.Count == 0)
return null;
foreach (MemberInfo m in move_next_list){
static bool TryType (Type t, ForeachHelperMethods hm)
{
- MemberInfo [] mi;
+ MemberList mi;
mi = TypeContainer.FindMembers (t, MemberTypes.Method,
BindingFlags.Public | BindingFlags.NonPublic |
BindingFlags.Instance,
FilterEnumerator, hm);
- if (mi == null || mi.Length == 0)
+ if (mi.Count == 0)
return false;
hm.get_enumerator = (MethodInfo) mi [0];
return false;
}
- public override bool Emit (EmitContext ec)
+ protected override bool DoEmit (EmitContext ec)
{
bool ret_val;
}
}
}
-
projects / mono.git / blobdiff