Files
swift-mirror/lib/SILPasses/Utils/Generics.cpp
Doug Gregor 4ed45ec830 Revert "Generic specializer: don't allow specialization if it uses an incomplete conformance."
This reverts r27886; a better solution is coming.

Swift SVN r27895
2015-04-29 00:08:26 +00:00

122 lines
4.3 KiB
C++

//===- Generics.cpp ---- Utilities for transforming generics ----*- C++ -*-===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "generic-specializer-utility"
#include "swift/SILPasses/Utils/Generics.h"
#include "swift/SILPasses/Utils/GenericCloner.h"
using namespace swift;
// Create a new apply based on an old one, but with a different
// function being applied.
static ApplySite replaceWithSpecializedFunction(ApplySite AI,
SILFunction *NewF) {
SILLocation Loc = AI.getLoc();
ArrayRef<Substitution> Subst;
SmallVector<SILValue, 4> Arguments;
for (auto &Op : AI.getArgumentOperands()) {
Arguments.push_back(Op.get());
}
SILBuilderWithScope<2> Builder(AI.getInstruction());
FunctionRefInst *FRI = Builder.createFunctionRef(Loc, NewF);
if (auto *TAI = dyn_cast<TryApplyInst>(AI))
return Builder.createTryApply(Loc, FRI, TAI->getSubstCalleeSILType(),
{}, Arguments, TAI->getNormalBB(),
TAI->getErrorBB());
if (isa<ApplyInst>(AI))
return Builder.createApply(Loc, FRI, Arguments);
if (auto *PAI = dyn_cast<PartialApplyInst>(AI))
return Builder.createPartialApply(Loc, FRI,
PAI->getSubstCalleeSILType(),
{},
Arguments,
PAI->getType());
llvm_unreachable("unhandled kind of apply");
}
ApplySite swift::trySpecializeApplyOfGeneric(ApplySite Apply,
SILFunction *&NewFunction,
llvm::SmallVectorImpl<FullApplyCollector::value_type> &NewApplyPairs) {
NewFunction = nullptr;
assert(NewApplyPairs.empty() && "Expected no new applies in vector yet!");
assert(Apply.hasSubstitutions() && "Expected an apply with substitutions!");
auto *F = cast<FunctionRefInst>(Apply.getCallee())->getReferencedFunction();
assert(F->isDefinition() && "Expected definition to specialize!");
DEBUG(llvm::dbgs() << " ApplyInst: " << *Apply.getInstruction());
// Create the substitution maps.
TypeSubstitutionMap InterfaceSubs
= F->getLoweredFunctionType()->getGenericSignature()
->getSubstitutionMap(Apply.getSubstitutions());
TypeSubstitutionMap ContextSubs
= F->getContextGenericParams()
->getSubstitutionMap(Apply.getSubstitutions());
// We do not support partial specialization.
if (hasUnboundGenericTypes(InterfaceSubs)) {
DEBUG(llvm::dbgs() << " Can not specialize with interface subs.\n");
return ApplySite();
}
llvm::SmallString<64> ClonedName;
{
llvm::raw_svector_ostream buffer(ClonedName);
ArrayRef<Substitution> Subs = Apply.getSubstitutions();
Mangle::Mangler M(buffer);
Mangle::GenericSpecializationMangler Mangler(M, F, Subs);
Mangler.mangle();
}
SILFunction *NewF;
auto &M = Apply.getInstruction()->getModule();
// If we already have this specialization, reuse it.
if (auto PrevF = M.lookUpFunction(ClonedName)) {
NewF = PrevF;
#ifndef NDEBUG
// Make sure that NewF's subst type matches the expected type.
auto Subs = Apply.getSubstitutions();
auto FTy =
F->getLoweredFunctionType()->substGenericArgs(M,
M.getSwiftModule(),
Subs);
assert(FTy == NewF->getLoweredFunctionType() &&
"Previously specialized function does not match expected type.");
#endif
} else {
FullApplyCollector Collector;
// Create a new function.
NewF = GenericCloner::cloneFunction(F, InterfaceSubs, ContextSubs,
ClonedName, Apply,
Collector.getCallback());
for (auto &P : Collector.getApplyPairs())
NewApplyPairs.push_back(P);
NewFunction = NewF;
}
return replaceWithSpecializedFunction(Apply, NewF);
}