/// <summary>
/// Test two conditions, and conditionally branch vs. fall through:
/// either branch to target or fall through to subsequent code;
/// conditions are and'ed together: both together constitute "true".
/// Another way of thinking of this is condition conjunction (both).
/// </summary>
/// <param name="left">
/// Initial/left test condition.
/// </param>
/// <param name="right">
/// Initial/right test condition -- possibly short-circuted.
/// </param>
/// <param name="target">
/// Conditional branch target (or else fall thru).
/// </param>
/// <param name="reverse">
/// false --> normal case, fall through on both true, otherwise on false: branch to target
/// true --> reversed case, fall through at least one false, otherwise on true: branch to target
/// </param>
public void EvalBoth(AbstractSyntaxTree left, AbstractSyntaxTree right, BranchTargetLabel target, bool reverse)
{
// NB: "Both" means evaluating left/first and right/second operands in the normal way.
// Each operand is evaluated to branch around the then-part or loop-body on condition false,
// and fall thru into the then-part or loop-body on condition true (both sub conditions being true).
left.GenerateCodeForConditionalBranchWithPrettyPrint(this, target, reverse);
right.GenerateCodeForConditionalBranchWithPrettyPrint(this, target, reverse);
}
/// <summary>
/// Test two conditions, and conditionally branch vs. fall through:
/// either branch to target or fall through to subsequent code;
/// conditions are or'ed together: either one constitutes "true".
/// Another way of thinking of this is condition disjunction (i.e. either).
/// </summary>
/// <param name="left">
/// Initial/left test condition.
/// </param>
/// <param name="right">
/// Initial/right test condition -- possibly short-circuted.
/// </param>
/// <param name="target">
/// Conditional branch target (or else fall thru).
/// </param>
/// <param name="reverse">
/// false --> normal case, fall through to following code on at least one true, otherwise on false: branch to target
/// true --> reversed case, fall through both false, otherwise on true: branch to target
/// </param>
public void EvalEither(AbstractSyntaxTree left, AbstractSyntaxTree right, BranchTargetLabel target, bool reverse)
{
// NB: "Either" means evaluating left/first operand, and on true, taking branch around the right/second operand
// and into the fall thru code of the then-part or loop-body!
// This requires use of an intermediate label, and a reversal of the evaluation condition, but only for the left/first operand.
// The second operand is evaluated as per normal, take brach around the then-part or loop-body on condition false.
var around = CreateLabel();
left.GenerateCodeForConditionalBranchWithPrettyPrint(this, around, !reverse);
right.GenerateCodeForConditionalBranchWithPrettyPrint(this, target, reverse);
PlaceLabelHere(around);
}