private void GenerateSwitchForDiscriminator(ILGenerator gen, GenerateUnionCaseAction action,
Label afterSwitchBlock) {
// process all switch cases stored ...
// generate the following structure:
// ldarg.0 // start case-1 test
// push first discr constant for switch case considered
// beq case1
// ldarg.0
// push next (if present) discr constant for switch case considered
// beq case1
//
// ldarg.0 // start case-2 test
// push first discr constant for switch case considered
// beq case2
// ...
// br default
// case1 :
// ...
// br end
// case2 :
// ...
// br end
// default:
// ...
Label defaultCaseLabel = gen.DefineLabel(); // make sure to have default case, even if no default is specified in IDL
// part1: compare and jump
foreach (SwitchCase switchCase in m_switchCases) {
if (switchCase.IsDefaultCase()) {
// generate the default case at the end, no comparison needed for default case
continue;
}
// generate and assign label to the current case
switchCase.AssignIlLabel(gen);
for (int j = 0; j < switchCase.DiscriminatorValues.Length; j++) {
// generate tests
action.GenerateLoadDiscValue(gen);
PushDiscriminatorValueToStack(gen, switchCase.DiscriminatorValues[j]);
gen.Emit(OpCodes.Beq, switchCase.IlLabelAssigned);
}
}
// if nothing found, jump to default case
gen.Emit(OpCodes.Br, defaultCaseLabel);
// part2: code for cases (jump-targets)
SwitchCase defaultCaseFound = null;
foreach (SwitchCase switchCase in m_switchCases) {
if (switchCase.IsDefaultCase()) {
// make sure to generate the default case at the end, not in between
defaultCaseFound = switchCase;
continue;
}
// set position for the case label
gen.MarkLabel(switchCase.IlLabelAssigned);
// the field to return
action.GenerateCaseAction(gen, switchCase, false);
gen.Emit(OpCodes.Br, afterSwitchBlock); // jump to exit point
}
// the default case
gen.MarkLabel(defaultCaseLabel);
if (defaultCaseFound != null) {
// a default case present
action.GenerateCaseAction(gen, defaultCaseFound, true);
} else {
action.GenerateNoDefaultCasePresent(gen);
}
gen.Emit(OpCodes.Br_S, afterSwitchBlock); // jump to exit point
}
private void GenerateSwitchForDiscriminator(ILGenerator gen, GenerateUnionCaseAction action,
Label afterSwitchBlock)
{
// process all switch cases stored ...
// generate the following structure:
// ldarg.0 // start case-1 test
// push first discr constant for switch case considered
// beq case1
// ldarg.0
// push next (if present) discr constant for switch case considered
// beq case1
//
// ldarg.0 // start case-2 test
// push first discr constant for switch case considered
// beq case2
// ...
// br default
// case1 :
// ...
// br end
// case2 :
// ...
// br end
// default:
// ...
Label defaultCaseLabel = gen.DefineLabel(); // make sure to have default case, even if no default is specified in IDL
// part1: compare and jump
foreach (SwitchCase switchCase in m_switchCases)
{
if (switchCase.IsDefaultCase())
{
// generate the default case at the end, no comparison needed for default case
continue;
}
// generate and assign label to the current case
switchCase.AssignIlLabel(gen);
for (int j = 0; j < switchCase.DiscriminatorValues.Length; j++)
{
// generate tests
action.GenerateLoadDiscValue(gen);
PushDiscriminatorValueToStack(gen, switchCase.DiscriminatorValues[j]);
gen.Emit(OpCodes.Beq, switchCase.IlLabelAssigned);
}
}
// if nothing found, jump to default case
gen.Emit(OpCodes.Br, defaultCaseLabel);
// part2: code for cases (jump-targets)
SwitchCase defaultCaseFound = null;
foreach (SwitchCase switchCase in m_switchCases)
{
if (switchCase.IsDefaultCase())
{
// make sure to generate the default case at the end, not in between
defaultCaseFound = switchCase;
continue;
}
// set position for the case label
gen.MarkLabel(switchCase.IlLabelAssigned);
// the field to return
action.GenerateCaseAction(gen, switchCase, false);
gen.Emit(OpCodes.Br, afterSwitchBlock); // jump to exit point
}
// the default case
gen.MarkLabel(defaultCaseLabel);
if (defaultCaseFound != null)
{
// a default case present
action.GenerateCaseAction(gen, defaultCaseFound, true);
}
else
{
action.GenerateNoDefaultCasePresent(gen);
}
gen.Emit(OpCodes.Br_S, afterSwitchBlock); // jump to exit point
}
