/// <summary>
/// Lowers generic values containing structure types that cannot be rewritten.
/// </summary>
private static void Keep(
SSARewriterContext <FieldRef> context,
LoweringData _,
Value value) =>
DisassembleStructure(
context,
value.Type.As <StructureType>(value),
value);
/// <summary>
/// Keeps structure load operations.
/// </summary>
private static void Keep(
SSARewriterContext <FieldRef> context,
LoweringData _,
Load load) =>
DisassembleStructure(
context,
load.Type as StructureType,
load);
/// <summary>
/// Lowers parameter values containing structure values.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
Parameter value) =>
DisassembleStructure(
context,
value.Type as StructureType,
value);
/// <summary>
/// Lowers sub-warp shuffles.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
SubWarpShuffle value) =>
LowerThreadValue <
SubWarpShuffle,
LowerThreadIntrinsics.SubWarpShuffleLowering>(
context,
value.Type as StructureType,
value);
/// <summary>
/// Lowers warp shuffles.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
Broadcast value) =>
LowerThreadValue <
Broadcast,
LowerThreadIntrinsics.BroadcastLowering>(
context,
value.Type as StructureType,
value);
/// <summary>
/// Keeps structure store operations.
/// </summary>
private static void Keep(
SSARewriterContext <FieldRef> context,
LoweringData _,
Store store)
{
var newValue = AssembleStructure(
context,
store.Value.Type as StructureType,
store.Value);
var newStore = context.Builder.CreateStore(
store.Location,
store.Target,
newValue);
context.ReplaceAndRemove(store, newStore);
}
/// <summary>
/// Lowers structure values into separate SSA values.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
StructureValue structureValue)
{
foreach (var(_, fieldAccess) in structureValue.StructureType)
{
// Build the new target value
var value = structureValue[fieldAccess.Index];
// Bind the new SSA value
context.SetValue(
context.Block,
new FieldRef(structureValue, fieldAccess),
value);
}
}
/// <summary>
/// Applies the structure lowering transformation.
/// </summary>
protected override bool PerformTransformation(Method.Builder builder)
{
var ssaBuilder = SSABuilder <FieldRef> .Create(builder);
var loweredPhis = new List <LoweredPhi>();
var loweringData = new LoweringData(loweredPhis);
bool applied = LowerLoadStores
? LoadStoreRewriter.Rewrite(ssaBuilder, loweringData)
: Rewriter.Rewrite(ssaBuilder, loweringData);
// Seal all lowered phis
foreach (var phi in loweredPhis)
{
var phiValue = phi.Seal(ssaBuilder);
phiValue.TryRemoveTrivialPhi(builder);
}
return(applied);
}
/// <summary>
/// Lowers null values into separate SSA values.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
NullValue nullValue)
{
foreach (var(fieldType, fieldAccess) in nullValue.Type as StructureType)
{
// Build the new target value
var value = context.Builder.CreateNull(
nullValue.Location,
fieldType);
context.MarkConverted(value);
// Bind the new SSA value
context.SetValue(
context.Block,
new FieldRef(nullValue, fieldAccess),
value);
}
}
/// <summary>
/// Lowers method calls involving structure types.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
MethodCall call)
{
// Check for structure arguments that need to be rebuilt
var newArgs = ImmutableArray.CreateBuilder <ValueReference>(
call.NumArguments);
foreach (Value argument in call)
{
Value newArgument = argument;
if (argument.Type is StructureType argumentType)
{
newArgument = AssembleStructure(
context,
argumentType,
argument);
}
newArgs.Add(newArgument);
}
// Create new call node
var newCall = context.Builder.CreateCall(
call.Location,
call.Target,
newArgs.MoveToImmutable());
context.ReplaceAndRemove(call, newCall);
// Convert the return value
if (call.Type is StructureType callType)
{
DisassembleStructure(
context,
callType,
newCall);
}
}
/// <summary>
/// Lowers return terminators returning structure values.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
ReturnTerminator value)
{
// Move the block builder to a valid insert position in the source block
var blockBuilder = context.GetMethodBuilder()[value.BasicBlock];
blockBuilder.SetupInsertPositionToEnd();
// Assemble return value
Value returnValue = value.ReturnValue;
var returnType = returnValue.Type.As <StructureType>(value);
var newReturnValue = AssembleStructure(
context.SpecializeBuilder(blockBuilder),
returnType,
returnValue);
// Replace return terminator with a new terminator
context.Builder.Terminator = context.Builder.CreateReturn(
value.Location,
newReturnValue);
}
/// <summary>
/// Lowers return terminators returning structure values.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
ReturnTerminator value)
{
Value returnValue = value.ReturnValue;
var returnType = returnValue.Type as StructureType;
Debug.Assert(returnType != null, "Invalid structure type");
// Assemble a new structure that can be returned
var blockBuilder = context.GetMethodBuilder()[value.BasicBlock];
blockBuilder.SetupInsertPosition(returnValue);
var newReturnValue = AssembleStructure(
context.SpecializeBuilder(blockBuilder),
returnType,
returnValue);
// Replace return and remove return value
returnValue.Replace(newReturnValue);
}
/// <summary>
/// Lowers set field operations into separate SSA values.
/// </summary>
private static void Lower(
SSARewriterContext <FieldRef> context,
LoweringData _,
SetField setField)
{
foreach (var(_, fieldAccess) in setField.Type as StructureType)
{
Value value;
if (setField.FieldSpan.Contains(fieldAccess))
{
// Get value from the source value
value = setField.Value;
if (value.Type is StructureType)
{
var getFieldAccess = fieldAccess.Subtract(
setField.FieldSpan.Index);
value = context.GetValue(
context.Block,
new FieldRef(value, getFieldAccess));
}
}
else
{
// Load the currently registered SSA value
value = context.GetValue(
context.Block,
new FieldRef(setField.ObjectValue, fieldAccess));
}
// Bind the mapped SSA value
context.SetValue(
context.Block,
new FieldRef(setField, fieldAccess),
value);
}
context.Remove(setField);
}
