Skip to content

Form a GenericSignatureBuilder for a RequirementEnvironment as needed. #12203

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 1, 2017
Merged

Form a GenericSignatureBuilder for a RequirementEnvironment as needed. #12203

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
35 changes: 24 additions & 11 deletions lib/Sema/TypeCheckProtocol.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -41,13 +41,16 @@
#include "swift/Serialization/SerializedModuleLoader.h"
#include "llvm/ADT/ScopedHashTable.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/SaveAndRestore.h"

#define DEBUG_TYPE "protocol-conformance-checking"
#define DEBUG_TYPE "Protocol conformance checking"
#include "llvm/Support/Debug.h"

STATISTIC(NumRequirementEnvironments, "# of requirement environments");

using namespace swift;

namespace {
Expand Down Expand Up @@ -1065,26 +1068,19 @@ RequirementEnvironment::RequirementEnvironment(
auto selfType = cast<GenericTypeParamType>(
proto->getSelfInterfaceType()->getCanonicalType());

// Construct a generic signature builder by collecting the constraints
// from the requirement and the context of the conformance together,
// because both define the capabilities of the requirement.
GenericSignatureBuilder builder(
ctx,
TypeChecker::LookUpConformance(tc, conformanceDC));

SmallVector<GenericTypeParamType*, 4> allGenericParams;

// Add the generic signature of the context of the conformance. This includes
// the generic parameters from the conforming type as well as any additional
// constraints that might occur on the extension that declares the
// conformance (i.e., if the conformance is conditional).
GenericSignature *conformanceSig;
unsigned depth = 0;
if (auto *conformanceSig = conformanceDC->getGenericSignatureOfContext()) {
if ((conformanceSig = conformanceDC->getGenericSignatureOfContext())) {
// Use the canonical signature here.
conformanceSig = conformanceSig->getCanonicalSignature();
allGenericParams.append(conformanceSig->getGenericParams().begin(),
conformanceSig->getGenericParams().end());
builder.addGenericSignature(conformanceSig);
depth = allGenericParams.back()->getDepth() + 1;
}

Expand Down Expand Up @@ -1138,12 +1134,29 @@ RequirementEnvironment::RequirementEnvironment(
GenericTypeParamType::get(depth, genericParam->getIndex(), ctx);

allGenericParams.push_back(substGenericParam);
builder.addGenericParameter(substGenericParam);
}

// If there were no generic parameters, we're done.
if (allGenericParams.empty()) return;

// Construct a generic signature builder by collecting the constraints
// from the requirement and the context of the conformance together,
// because both define the capabilities of the requirement.
GenericSignatureBuilder builder(
ctx,
TypeChecker::LookUpConformance(tc, conformanceDC));

unsigned firstGenericParamToAdd = 0;
if (conformanceSig) {
builder.addGenericSignature(conformanceSig);
firstGenericParamToAdd = conformanceSig->getGenericParams().size();
}

for (unsigned gp : range(firstGenericParamToAdd, allGenericParams.size()))
builder.addGenericParameter(allGenericParams[gp]);

++NumRequirementEnvironments;

// Next, add each of the requirements (mapped from the requirement's
// interface types into the abstract type parameters).
auto source =
Expand Down