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Previously, this asserted on unexpected situations that the optimizer couldn't handle. It makes more sense now to handle these cases conservatively since we can't catch them in early testing. Fixes <rdar://problem/35402799> [4.1] Assertion failed: (user->getResults().empty())
708 lines
24 KiB
C++
708 lines
24 KiB
C++
//===--- AccessEnforcementSelection.cpp - Select access enforcement -------===//
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//
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// This source file is part of the Swift.org open source project
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//
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// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
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// Licensed under Apache License v2.0 with Runtime Library Exception
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//
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// See https://swift.org/LICENSE.txt for license information
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// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
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//
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//===----------------------------------------------------------------------===//
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///
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/// This pass eliminates 'unknown' access enforcement by selecting either
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/// static or dynamic enforcement.
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///
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/// TODO: This is currently a module transform so that closures can be
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/// transformed after their parent scope is analyzed. This isn't a big problem
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/// now because AccessMarkerElimination is also a module pass that follows this
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/// pass. However, we would like to mostly eliminate module transforms. This
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/// could be done by changing the PassManager to follow CloseScopeAnalysis. A
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/// new ClosureTransform type would be pipelined just like FunctionTransform,
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/// but would have an entry point that handled a parent closure scope and all
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/// its children in one invocation. For function pipelining to be upheld, we
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/// would need to verify that BasicCalleeAnalysis never conflicts with
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/// ClosureScopeAnalysis. i.e. we could never create a caller->callee edge when
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/// the callee is passed as a function argument. Normal FunctionTransforms would
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/// then be called on each closure function and its parent scope before calling
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/// the ClosureTransform.
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///
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/// FIXME: handle boxes used by copy_value when neither copy is captured.
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///
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "access-enforcement-selection"
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#include "swift/SIL/SILArgument.h"
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#include "swift/SIL/SILFunction.h"
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#include "swift/SIL/SILUndef.h"
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#include "swift/SILOptimizer/Analysis/ClosureScope.h"
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#include "swift/SILOptimizer/PassManager/Transforms.h"
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using namespace swift;
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static void setStaticEnforcement(BeginAccessInst *access) {
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// TODO: delete if we're not using static enforcement?
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access->setEnforcement(SILAccessEnforcement::Static);
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DEBUG(llvm::dbgs() << "Static Access: " << *access);
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}
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static void setDynamicEnforcement(BeginAccessInst *access) {
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// TODO: delete if we're not using dynamic enforcement?
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access->setEnforcement(SILAccessEnforcement::Dynamic);
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DEBUG(llvm::dbgs() << "Dynamic Access: " << *access);
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}
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namespace {
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// Information about an address-type closure capture.
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// This is only valid for inout_aliasable parameters.
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//
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// TODO: Verify somewhere that we properly handle any non-inout_aliasable
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// partial apply captures or that they never happen. Eventually @inout_aliasable
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// should be simply replaced by @in or @out, once we don't have special aliasing
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// rules.
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struct AddressCapture {
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ApplySite site;
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unsigned calleeArgIdx;
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AddressCapture(Operand &oper)
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: site(oper.getUser()), calleeArgIdx(site.getCalleeArgIndex(oper)) {
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assert(isa<PartialApplyInst>(site));
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if (site.getOrigCalleeConv().getSILArgumentConvention(calleeArgIdx)
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!= SILArgumentConvention::Indirect_InoutAliasable) {
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site = ApplySite();
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calleeArgIdx = ~0U;
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return;
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}
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assert(oper.get()->getType().isAddress());
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}
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bool isValid() const { return bool(site); }
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};
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raw_ostream &operator<<(raw_ostream &os, const AddressCapture &capture) {
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os << *capture.site.getInstruction() << " captures Arg #"
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<< capture.calleeArgIdx;
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auto *F = capture.site.getCalleeFunction();
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if (F)
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os << " of " << F->getName();
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os << '\n';
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return os;
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}
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// For each non-escaping closure, record the indices of arguments that
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// require dynamic enforcement.
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class DynamicCaptures {
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llvm::DenseMap<SILFunction *, SmallVector<unsigned, 4>> dynamicCaptureMap;
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DynamicCaptures(DynamicCaptures &) = delete;
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public:
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DynamicCaptures() = default;
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void recordCapture(AddressCapture capture) {
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DEBUG(llvm::dbgs() << "Dynamic Capture: " << capture);
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auto callee = capture.site.getCalleeFunction();
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assert(callee && "cannot locate function ref for nonescaping closure");
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auto &dynamicArgs = dynamicCaptureMap[callee];
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if (!llvm::is_contained(dynamicArgs, capture.calleeArgIdx))
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dynamicArgs.push_back(capture.calleeArgIdx);
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}
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bool isDynamic(SILFunctionArgument *arg) const {
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auto pos = dynamicCaptureMap.find(arg->getFunction());
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if (pos == dynamicCaptureMap.end())
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return false;
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auto &dynamicArgs = pos->second;
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return llvm::is_contained(dynamicArgs, arg->getIndex());
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}
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};
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} // anonymous namespace
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namespace {
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class SelectEnforcement {
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// Reference back to the known dynamically enforced non-escaping closure
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// arguments in this module. Parent scopes are processed before the closures
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// they reference.
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DynamicCaptures &dynamicCaptures;
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AllocBoxInst *Box;
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/// A state for tracking escape information about a variable.
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/// StateMap only has entries for blocks for which the variable
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/// has potentially escaped at exit.
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struct State {
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bool IsInWorklist = false;
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// At least one of the following must be true.
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bool HasEscape = false;
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bool HasPotentiallyEscapedAtEntry = false;
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// In a more advanced problem, this could easily be passed a State.
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bool adjustForEscapeInPredecessor() {
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bool updateSuccessors = false;
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if (!HasPotentiallyEscapedAtEntry) {
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HasPotentiallyEscapedAtEntry = true;
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updateSuccessors = !HasEscape;
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}
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return updateSuccessors;
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}
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};
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llvm::DenseMap<SILBasicBlock*, State> StateMap;
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/// All the accesses of Box in the function.
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SmallVector<BeginAccessInst*, 8> Accesses;
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/// All the non-escaping closure captures of the Boxed value in this function.
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SmallVector<AddressCapture, 8> Captures;
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/// All the escapes in the function.
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SmallPtrSet<SILInstruction*, 8> Escapes;
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/// A worklist we use for various purposes.
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SmallVector<SILBasicBlock*, 8> Worklist;
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public:
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SelectEnforcement(DynamicCaptures &dc, AllocBoxInst *box)
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: dynamicCaptures(dc), Box(box) {}
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void run();
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private:
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void analyzeUsesOfBox(SingleValueInstruction *source);
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void analyzeProjection(ProjectBoxInst *projection);
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/// Note that the given instruction is a use of the box (or a use of
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/// a projection from it) in which the address escapes.
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void noteEscapingUse(SILInstruction *inst);
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void propagateEscapes();
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void propagateEscapesFrom(SILBasicBlock *bb);
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bool hasPotentiallyEscapedAt(SILInstruction *inst);
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typedef llvm::SmallSetVector<SILBasicBlock*, 8> BlockSetVector;
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void findBlocksAccessedAcross(EndAccessInst *endAccess,
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BlockSetVector &blocksAccessedAcross);
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bool hasPotentiallyEscapedAtAnyReachableBlock(
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BeginAccessInst *access, BlockSetVector &blocksAccessedAcross);
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void updateAccesses();
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void updateAccess(BeginAccessInst *access);
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void updateCapture(AddressCapture capture);
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};
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} // end anonymous namespace
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void SelectEnforcement::run() {
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DEBUG(llvm::dbgs() << " Box: " << *Box);
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// Set up the data-flow problem.
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analyzeUsesOfBox(Box);
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// Run the data-flow problem.
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propagateEscapes();
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// Update all the accesses.
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updateAccesses();
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}
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// FIXME: This should cover a superset of AllocBoxToStack's findUnexpectedBoxUse
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// to avoid perturbing codegen. They should be sharing the same analysis.
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void SelectEnforcement::analyzeUsesOfBox(SingleValueInstruction *source) {
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// Collect accesses rooted off of projections.
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for (auto use : source->getUses()) {
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auto user = use->getUser();
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if (auto MUI = dyn_cast<MarkUninitializedInst>(user)) {
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analyzeUsesOfBox(MUI);
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continue;
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}
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if (auto projection = dyn_cast<ProjectBoxInst>(user)) {
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analyzeProjection(projection);
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continue;
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}
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// Ignore certain other uses that do not capture the value.
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if (isa<StrongRetainInst>(user) ||
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isa<StrongReleaseInst>(user) ||
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isa<DestroyValueInst>(user) ||
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isa<DeallocBoxInst>(user))
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continue;
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// Treat everything else as an escape.
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// A Box typically escapes via copy_value.
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noteEscapingUse(user);
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}
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// Accesses may still be empty if the user of the Box is a partial apply
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// capture and, for some reason, the closure is dead.
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}
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void SelectEnforcement::analyzeProjection(ProjectBoxInst *projection) {
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for (auto *use : projection->getUses()) {
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auto user = use->getUser();
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// Collect accesses.
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if (auto *access = dyn_cast<BeginAccessInst>(user)) {
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if (access->getEnforcement() == SILAccessEnforcement::Unknown)
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Accesses.push_back(access);
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continue;
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}
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if (isa<PartialApplyInst>(user))
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Captures.emplace_back(AddressCapture(*use));
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}
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}
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void SelectEnforcement::noteEscapingUse(SILInstruction *inst) {
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DEBUG(llvm::dbgs() << " Escape: " << *inst);
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// Add it to the escapes set.
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Escapes.insert(inst);
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// Record this point as escaping.
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auto userBB = inst->getParent();
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auto &state = StateMap[userBB];
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if (!state.IsInWorklist) {
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state.HasEscape = true;
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state.IsInWorklist = true;
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Worklist.push_back(userBB);
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}
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assert(state.HasEscape);
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assert(state.IsInWorklist);
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}
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void SelectEnforcement::propagateEscapes() {
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while (!Worklist.empty()) {
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auto bb = Worklist.pop_back_val();
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auto it = StateMap.find(bb);
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assert(it != StateMap.end() &&
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"block was in worklist but doesn't have a tracking state");
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auto &state = it->second;
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assert(state.HasEscape || state.HasPotentiallyEscapedAtEntry);
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state.IsInWorklist = false;
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propagateEscapesFrom(bb);
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}
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}
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/// Given that the box potentially escaped before we exited the
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/// given block, propagate that information to all of its successors.
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void SelectEnforcement::propagateEscapesFrom(SILBasicBlock *bb) {
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assert(StateMap.count(bb));
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// Iterate over the successors of the block.
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for (SILBasicBlock *succ : bb->getSuccessors()) {
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auto &succState = StateMap[succ];
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// If updating the successor changes it in a way that will
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// require us to update its successors, add it to the worklist.
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if (succState.adjustForEscapeInPredecessor()) {
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if (!succState.IsInWorklist) {
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succState.IsInWorklist = true;
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Worklist.push_back(succ);
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}
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}
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}
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}
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bool SelectEnforcement::hasPotentiallyEscapedAt(SILInstruction *point) {
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auto bb = point->getParent();
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// If we're not tracking anything for the whole block containing
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// the instruction, we're done; it hasn't escaped here.
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auto it = StateMap.find(bb);
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if (it == StateMap.end())
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return false;
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// If the tracking information says there are escapes before entry,
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// we're done; it has potentially escaped.
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const auto &state = it->second;
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if (state.HasPotentiallyEscapedAtEntry)
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return true;
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// Okay, there must be an escape within this block.
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assert(state.HasEscape);
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for (auto ii = point->getIterator(), ie = bb->begin(); ii != ie; ) {
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auto inst = &*--ii;
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// Maybe just record the first escape in the block and see if we
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// come after it?
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if (Escapes.count(inst))
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return true;
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}
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return false;
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}
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/// Add all blocks to `Worklist` between the given `endAccess` and its
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/// `begin_access` in which the access is active at the end of the block.
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void SelectEnforcement::findBlocksAccessedAcross(
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EndAccessInst *endAccess, BlockSetVector &blocksAccessedAcross) {
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// Fast path: we're not tracking any escapes. (But the box should
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// probably have been promoted to the stack in this case.)
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if (StateMap.empty())
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return;
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SILBasicBlock *beginBB = endAccess->getBeginAccess()->getParent();
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if (endAccess->getParent() == beginBB)
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return;
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assert(Worklist.empty());
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Worklist.push_back(endAccess->getParent());
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while (!Worklist.empty()) {
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SILBasicBlock *bb = Worklist.pop_back_val();
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for (auto *predBB : bb->getPredecessorBlocks()) {
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if (!blocksAccessedAcross.insert(predBB)) continue;
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if (predBB == beginBB) continue;
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Worklist.push_back(predBB);
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}
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}
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}
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bool SelectEnforcement::hasPotentiallyEscapedAtAnyReachableBlock(
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BeginAccessInst *access, BlockSetVector &blocksAccessedAcross) {
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assert(Worklist.empty());
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SmallPtrSet<SILBasicBlock*, 8> visited;
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// Don't follow any paths that lead to an end_access.
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for (auto endAccess : access->getEndAccesses())
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visited.insert(endAccess->getParent());
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/// Initialize the worklist with all blocks that exit the access path.
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for (SILBasicBlock *bb : blocksAccessedAcross) {
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for (SILBasicBlock *succBB : bb->getSuccessorBlocks()) {
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if (blocksAccessedAcross.count(succBB)) continue;
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if (visited.insert(succBB).second)
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Worklist.push_back(succBB);
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}
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}
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while (!Worklist.empty()) {
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SILBasicBlock *bb = Worklist.pop_back_val();
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assert(visited.count(bb));
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// If we're tracking information for this block, there's an escape.
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if (StateMap.count(bb))
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return true;
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// Add all reachable successors.
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for (SILBasicBlock *succ : bb->getSuccessors()) {
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if (visited.insert(succ).second)
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Worklist.push_back(succ);
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}
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}
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// No reachable block has an escape.
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return false;
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}
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void SelectEnforcement::updateAccesses() {
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for (auto *access : Accesses) {
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DEBUG(llvm::dbgs() << " Access: " << *access);
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updateAccess(access);
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}
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for (AddressCapture &capture : Captures) {
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DEBUG(llvm::dbgs() << " Capture: " << capture);
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updateCapture(capture);
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}
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}
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void SelectEnforcement::updateAccess(BeginAccessInst *access) {
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assert(access->getEnforcement() == SILAccessEnforcement::Unknown);
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// Check whether the variable escaped before any of the end_accesses.
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BlockSetVector blocksAccessedAcross;
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for (auto endAccess : access->getEndAccesses()) {
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if (hasPotentiallyEscapedAt(endAccess))
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return setDynamicEnforcement(access);
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// Add all blocks to blocksAccessedAcross between begin_access and this
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// end_access.
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findBlocksAccessedAcross(endAccess, blocksAccessedAcross);
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}
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assert(blocksAccessedAcross.empty()
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|| blocksAccessedAcross.count(access->getParent()));
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// For every path through this access that doesn't reach an end_access, check
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// if any block reachable from that path can see an escaped value.
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if (hasPotentiallyEscapedAtAnyReachableBlock(access, blocksAccessedAcross)) {
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setDynamicEnforcement(access);
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return;
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}
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// Otherwise, use static enforcement.
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setStaticEnforcement(access);
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}
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void SelectEnforcement::updateCapture(AddressCapture capture) {
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auto captureIfEscaped = [&](SILInstruction *user) {
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if (hasPotentiallyEscapedAt(user))
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dynamicCaptures.recordCapture(capture);
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};
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llvm::SmallSetVector<SingleValueInstruction *, 8> worklist;
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auto visitUse = [&](Operand *oper) {
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auto *user = oper->getUser();
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if (FullApplySite::isa(user)) {
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// A call is considered a closure access regardless of whether it calls
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// the closure or accepts the closure as an argument.
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captureIfEscaped(user);
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return;
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}
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switch (user->getKind()) {
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case SILInstructionKind::ConvertFunctionInst:
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case SILInstructionKind::BeginBorrowInst:
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case SILInstructionKind::CopyValueInst:
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case SILInstructionKind::EnumInst:
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case SILInstructionKind::StructInst:
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case SILInstructionKind::TupleInst:
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case SILInstructionKind::PartialApplyInst:
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// Propagate the closure.
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worklist.insert(cast<SingleValueInstruction>(user));
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return;
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case SILInstructionKind::StrongRetainInst:
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case SILInstructionKind::StrongReleaseInst:
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case SILInstructionKind::DebugValueInst:
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case SILInstructionKind::DestroyValueInst:
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case SILInstructionKind::RetainValueInst:
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case SILInstructionKind::ReleaseValueInst:
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case SILInstructionKind::EndBorrowInst:
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// Benign use.
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return;
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case SILInstructionKind::TupleExtractInst:
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case SILInstructionKind::StructExtractInst:
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case SILInstructionKind::AssignInst:
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case SILInstructionKind::BranchInst:
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case SILInstructionKind::CondBranchInst:
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case SILInstructionKind::ReturnInst:
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case SILInstructionKind::StoreInst:
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// These are all valid partial_apply users, however we don't expect them
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// to occur with non-escaping closures. Handle them conservatively just in
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// case they occur.
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LLVM_FALLTHROUGH;
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default:
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DEBUG(llvm::dbgs() << " Unrecognized partial_apply user: " << *user);
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// Handle unknown uses conservatively by assuming a capture.
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captureIfEscaped(user);
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}
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};
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SingleValueInstruction *PAIUser = dyn_cast<PartialApplyInst>(capture.site);
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while (true) {
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for (auto *oper : PAIUser->getUses())
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visitUse(oper);
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if (worklist.empty())
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break;
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PAIUser = worklist.pop_back_val();
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}
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}
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namespace {
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// Model the kind of access needed based on analyzing the access's source.
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// This is either determined to be static or dynamic, or requires further
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// analysis of a boxed variable.
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struct SourceAccess {
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enum { StaticAccess, DynamicAccess, BoxAccess } kind;
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AllocBoxInst *allocBox;
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static SourceAccess getStaticAccess() { return {StaticAccess, nullptr}; }
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static SourceAccess getDynamicAccess() { return {DynamicAccess, nullptr}; }
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static SourceAccess getBoxedAccess(AllocBoxInst *inst) {
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return {BoxAccess, inst};
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}
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};
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/// The pass.
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class AccessEnforcementSelection : public SILModuleTransform {
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// Reference back to the known dynamically enforced non-escaping closure
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// arguments in this module. Parent scopes are processed before the closures
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// they reference.
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DynamicCaptures dynamicCaptures;
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// Per-function book-keeping. A box is processed the first time one of it's
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// accesses is handled. Don't process it again for subsequent accesses.
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llvm::DenseSet<AllocBoxInst *> handledBoxes;
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#ifndef NDEBUG
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llvm::DenseSet<SILFunction *> visited;
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#endif
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public:
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void run() override;
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protected:
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void processFunction(SILFunction *F);
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SourceAccess getAccessKindForBox(ProjectBoxInst *projection);
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SourceAccess getSourceAccess(SILValue address);
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void handlePartialApply(PartialApplyInst *PAI);
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void handleAccess(BeginAccessInst *access);
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};
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void AccessEnforcementSelection::run() {
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auto *CSA = getAnalysis<ClosureScopeAnalysis>();
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TopDownClosureFunctionOrder closureOrder(CSA);
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closureOrder.visitFunctions(
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[this](SILFunction *F) { this->processFunction(F); });
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}
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void AccessEnforcementSelection::processFunction(SILFunction *F) {
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DEBUG(llvm::dbgs() << "Access Enforcement Selection in " << F->getName()
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<< "\n");
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#ifndef NDEBUG
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auto *CSA = getAnalysis<ClosureScopeAnalysis>();
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if (isNonEscapingClosure(F->getLoweredFunctionType())) {
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for (auto *scopeF : CSA->getClosureScopes(F)) {
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DEBUG(llvm::dbgs() << " Parent scope: " << scopeF->getName() << "\n");
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assert(visited.count(scopeF));
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}
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}
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visited.insert(F);
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#endif
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|
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for (auto &bb : *F) {
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for (auto ii = bb.begin(), ie = bb.end(); ii != ie;) {
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SILInstruction *inst = &*ii;
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++ii;
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|
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if (auto access = dyn_cast<BeginAccessInst>(inst))
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handleAccess(access);
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else if (auto access = dyn_cast<BeginUnpairedAccessInst>(inst))
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assert(access->getEnforcement() == SILAccessEnforcement::Dynamic);
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else if(auto pa = dyn_cast<PartialApplyInst>(inst))
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handlePartialApply(pa);
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|
}
|
|
}
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invalidateAnalysis(F, SILAnalysis::InvalidationKind::Instructions);
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|
// There's no need to track handled boxes across functions.
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|
handledBoxes.clear();
|
|
}
|
|
|
|
SourceAccess
|
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AccessEnforcementSelection::getAccessKindForBox(ProjectBoxInst *projection) {
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SILValue source = projection->getOperand();
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if (auto *MUI = dyn_cast<MarkUninitializedInst>(source))
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|
source = MUI->getOperand();
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|
|
|
// If we didn't allocate the box, assume that we need to use
|
|
// dynamic enforcement.
|
|
// TODO: use static enforcement in certain provable cases.
|
|
auto box = dyn_cast<AllocBoxInst>(source);
|
|
if (!box)
|
|
return SourceAccess::getDynamicAccess();
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|
|
|
return SourceAccess::getBoxedAccess(box);
|
|
}
|
|
|
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SourceAccess AccessEnforcementSelection::getSourceAccess(SILValue address) {
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|
// Recurse through MarkUninitializedInst.
|
|
if (auto *MUI = dyn_cast<MarkUninitializedInst>(address))
|
|
return getSourceAccess(MUI->getOperand());
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|
|
|
if (auto box = dyn_cast<ProjectBoxInst>(address))
|
|
return getAccessKindForBox(box);
|
|
|
|
if (auto arg = dyn_cast<SILFunctionArgument>(address)) {
|
|
switch (arg->getArgumentConvention()) {
|
|
case SILArgumentConvention::Indirect_Inout:
|
|
// `inout` arguments are checked on the caller side, either statically
|
|
// or dynamically if necessary. The @inout does not alias and cannot
|
|
// escape within the callee, so static enforcement is always sufficient.
|
|
return SourceAccess::getStaticAccess();
|
|
|
|
case SILArgumentConvention::Indirect_InoutAliasable:
|
|
if (dynamicCaptures.isDynamic(arg))
|
|
return SourceAccess::getDynamicAccess();
|
|
|
|
return SourceAccess::getStaticAccess();
|
|
case SILArgumentConvention::Indirect_In:
|
|
case SILArgumentConvention::Indirect_In_Guaranteed:
|
|
// @in/@in_guaranteed cannot be mutably accessed, mutably captured, or
|
|
// passed as inout. @in/@in_guaranteed may be captured @inout_aliasable.
|
|
// (This is fairly horrible, but presumably Sema/SILGen made sure a copy
|
|
// wasn't needed?)
|
|
//
|
|
// FIXME: When we have borrowed arguments, a "read" needs to be enforced
|
|
// on the caller side.
|
|
return SourceAccess::getStaticAccess();
|
|
|
|
default:
|
|
llvm_unreachable("Expecting an inout argument.");
|
|
}
|
|
}
|
|
// If we're not accessing a box or argument, we must've lowered to a stack
|
|
// element. Other sources of access are either outright dynamic (GlobalAddr,
|
|
// RefElementAddr), or only exposed after mandatory inlining (nested
|
|
// dependent BeginAccess).
|
|
//
|
|
// Running before diagnostic constant propagation requires handling 'undef'.
|
|
assert(isa<AllocStackInst>(address) || isa<SILUndef>(address));
|
|
return SourceAccess::getStaticAccess();
|
|
}
|
|
|
|
void AccessEnforcementSelection::handlePartialApply(PartialApplyInst *PAI) {
|
|
ApplySite site(PAI);
|
|
auto calleeTy = PAI->getOrigCalleeType();
|
|
SILFunctionConventions calleeConv(calleeTy, *getModule());
|
|
|
|
for (Operand &oper : site.getArgumentOperands()) {
|
|
AddressCapture capture(oper);
|
|
if (!capture.isValid())
|
|
continue;
|
|
|
|
// This partial apply creates a non-escaping closure. Check if the closure
|
|
// captures any Boxed variables from this scope. If so, check if the box
|
|
// escapes before the access just as we do for normal accesses.
|
|
auto sourceAccess = getSourceAccess(oper.get());
|
|
switch (sourceAccess.kind) {
|
|
case SourceAccess::StaticAccess:
|
|
// If the captured variable does not require dynamic enforcement, then
|
|
// there's no need to track it.
|
|
break;
|
|
case SourceAccess::DynamicAccess: {
|
|
dynamicCaptures.recordCapture(capture);
|
|
break;
|
|
}
|
|
case SourceAccess::BoxAccess:
|
|
if (handledBoxes.insert(sourceAccess.allocBox).second)
|
|
SelectEnforcement(dynamicCaptures, sourceAccess.allocBox).run();
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void AccessEnforcementSelection::handleAccess(BeginAccessInst *access) {
|
|
if (access->getEnforcement() != SILAccessEnforcement::Unknown)
|
|
return;
|
|
|
|
auto sourceAccess = getSourceAccess(access->getOperand());
|
|
switch (sourceAccess.kind) {
|
|
case SourceAccess::StaticAccess:
|
|
setStaticEnforcement(access);
|
|
break;
|
|
case SourceAccess::DynamicAccess:
|
|
setDynamicEnforcement(access);
|
|
break;
|
|
case SourceAccess::BoxAccess:
|
|
// If this box was handled, the access enforcement would already be set.
|
|
assert(!handledBoxes.count(sourceAccess.allocBox));
|
|
SelectEnforcement(dynamicCaptures, sourceAccess.allocBox).run();
|
|
break;
|
|
}
|
|
}
|
|
|
|
} // end anonymous namespace
|
|
|
|
SILTransform *swift::createAccessEnforcementSelection() {
|
|
return new AccessEnforcementSelection();
|
|
}
|