2032 lines
85 KiB
C++
2032 lines
85 KiB
C++
//===--- SemaLambda.cpp - Semantic Analysis for C++11 Lambdas -------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements semantic analysis for C++ lambda expressions.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/Sema/DeclSpec.h"
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#include "TypeLocBuilder.h"
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#include "clang/AST/ASTLambda.h"
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#include "clang/AST/ExprCXX.h"
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#include "clang/Basic/TargetInfo.h"
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#include "clang/Sema/Initialization.h"
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#include "clang/Sema/Lookup.h"
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#include "clang/Sema/Scope.h"
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#include "clang/Sema/ScopeInfo.h"
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#include "clang/Sema/SemaInternal.h"
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#include "clang/Sema/SemaLambda.h"
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#include "llvm/ADT/STLExtras.h"
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using namespace clang;
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using namespace sema;
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/// Examines the FunctionScopeInfo stack to determine the nearest
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/// enclosing lambda (to the current lambda) that is 'capture-ready' for
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/// the variable referenced in the current lambda (i.e. \p VarToCapture).
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/// If successful, returns the index into Sema's FunctionScopeInfo stack
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/// of the capture-ready lambda's LambdaScopeInfo.
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///
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/// Climbs down the stack of lambdas (deepest nested lambda - i.e. current
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/// lambda - is on top) to determine the index of the nearest enclosing/outer
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/// lambda that is ready to capture the \p VarToCapture being referenced in
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/// the current lambda.
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/// As we climb down the stack, we want the index of the first such lambda -
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/// that is the lambda with the highest index that is 'capture-ready'.
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///
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/// A lambda 'L' is capture-ready for 'V' (var or this) if:
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/// - its enclosing context is non-dependent
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/// - and if the chain of lambdas between L and the lambda in which
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/// V is potentially used (i.e. the lambda at the top of the scope info
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/// stack), can all capture or have already captured V.
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/// If \p VarToCapture is 'null' then we are trying to capture 'this'.
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///
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/// Note that a lambda that is deemed 'capture-ready' still needs to be checked
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/// for whether it is 'capture-capable' (see
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/// getStackIndexOfNearestEnclosingCaptureCapableLambda), before it can truly
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/// capture.
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///
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/// \param FunctionScopes - Sema's stack of nested FunctionScopeInfo's (which a
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/// LambdaScopeInfo inherits from). The current/deepest/innermost lambda
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/// is at the top of the stack and has the highest index.
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/// \param VarToCapture - the variable to capture. If NULL, capture 'this'.
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///
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/// \returns An Optional<unsigned> Index that if evaluates to 'true' contains
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/// the index (into Sema's FunctionScopeInfo stack) of the innermost lambda
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/// which is capture-ready. If the return value evaluates to 'false' then
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/// no lambda is capture-ready for \p VarToCapture.
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static inline Optional<unsigned>
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getStackIndexOfNearestEnclosingCaptureReadyLambda(
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ArrayRef<const clang::sema::FunctionScopeInfo *> FunctionScopes,
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VarDecl *VarToCapture) {
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// Label failure to capture.
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const Optional<unsigned> NoLambdaIsCaptureReady;
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// Ignore all inner captured regions.
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unsigned CurScopeIndex = FunctionScopes.size() - 1;
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while (CurScopeIndex > 0 && isa<clang::sema::CapturedRegionScopeInfo>(
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FunctionScopes[CurScopeIndex]))
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--CurScopeIndex;
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assert(
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isa<clang::sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]) &&
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"The function on the top of sema's function-info stack must be a lambda");
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// If VarToCapture is null, we are attempting to capture 'this'.
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const bool IsCapturingThis = !VarToCapture;
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const bool IsCapturingVariable = !IsCapturingThis;
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// Start with the current lambda at the top of the stack (highest index).
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DeclContext *EnclosingDC =
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cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex])->CallOperator;
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do {
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const clang::sema::LambdaScopeInfo *LSI =
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cast<sema::LambdaScopeInfo>(FunctionScopes[CurScopeIndex]);
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// IF we have climbed down to an intervening enclosing lambda that contains
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// the variable declaration - it obviously can/must not capture the
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// variable.
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// Since its enclosing DC is dependent, all the lambdas between it and the
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// innermost nested lambda are dependent (otherwise we wouldn't have
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// arrived here) - so we don't yet have a lambda that can capture the
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// variable.
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if (IsCapturingVariable &&
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VarToCapture->getDeclContext()->Equals(EnclosingDC))
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return NoLambdaIsCaptureReady;
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// For an enclosing lambda to be capture ready for an entity, all
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// intervening lambda's have to be able to capture that entity. If even
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// one of the intervening lambda's is not capable of capturing the entity
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// then no enclosing lambda can ever capture that entity.
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// For e.g.
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// const int x = 10;
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// [=](auto a) { #1
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// [](auto b) { #2 <-- an intervening lambda that can never capture 'x'
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// [=](auto c) { #3
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// f(x, c); <-- can not lead to x's speculative capture by #1 or #2
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// }; }; };
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// If they do not have a default implicit capture, check to see
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// if the entity has already been explicitly captured.
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// If even a single dependent enclosing lambda lacks the capability
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// to ever capture this variable, there is no further enclosing
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// non-dependent lambda that can capture this variable.
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if (LSI->ImpCaptureStyle == sema::LambdaScopeInfo::ImpCap_None) {
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if (IsCapturingVariable && !LSI->isCaptured(VarToCapture))
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return NoLambdaIsCaptureReady;
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if (IsCapturingThis && !LSI->isCXXThisCaptured())
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return NoLambdaIsCaptureReady;
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}
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EnclosingDC = getLambdaAwareParentOfDeclContext(EnclosingDC);
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assert(CurScopeIndex);
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--CurScopeIndex;
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} while (!EnclosingDC->isTranslationUnit() &&
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EnclosingDC->isDependentContext() &&
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isLambdaCallOperator(EnclosingDC));
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assert(CurScopeIndex < (FunctionScopes.size() - 1));
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// If the enclosingDC is not dependent, then the immediately nested lambda
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// (one index above) is capture-ready.
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if (!EnclosingDC->isDependentContext())
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return CurScopeIndex + 1;
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return NoLambdaIsCaptureReady;
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}
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/// Examines the FunctionScopeInfo stack to determine the nearest
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/// enclosing lambda (to the current lambda) that is 'capture-capable' for
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/// the variable referenced in the current lambda (i.e. \p VarToCapture).
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/// If successful, returns the index into Sema's FunctionScopeInfo stack
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/// of the capture-capable lambda's LambdaScopeInfo.
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///
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/// Given the current stack of lambdas being processed by Sema and
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/// the variable of interest, to identify the nearest enclosing lambda (to the
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/// current lambda at the top of the stack) that can truly capture
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/// a variable, it has to have the following two properties:
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/// a) 'capture-ready' - be the innermost lambda that is 'capture-ready':
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/// - climb down the stack (i.e. starting from the innermost and examining
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/// each outer lambda step by step) checking if each enclosing
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/// lambda can either implicitly or explicitly capture the variable.
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/// Record the first such lambda that is enclosed in a non-dependent
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/// context. If no such lambda currently exists return failure.
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/// b) 'capture-capable' - make sure the 'capture-ready' lambda can truly
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/// capture the variable by checking all its enclosing lambdas:
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/// - check if all outer lambdas enclosing the 'capture-ready' lambda
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/// identified above in 'a' can also capture the variable (this is done
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/// via tryCaptureVariable for variables and CheckCXXThisCapture for
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/// 'this' by passing in the index of the Lambda identified in step 'a')
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///
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/// \param FunctionScopes - Sema's stack of nested FunctionScopeInfo's (which a
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/// LambdaScopeInfo inherits from). The current/deepest/innermost lambda
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/// is at the top of the stack.
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///
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/// \param VarToCapture - the variable to capture. If NULL, capture 'this'.
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///
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///
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/// \returns An Optional<unsigned> Index that if evaluates to 'true' contains
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/// the index (into Sema's FunctionScopeInfo stack) of the innermost lambda
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/// which is capture-capable. If the return value evaluates to 'false' then
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/// no lambda is capture-capable for \p VarToCapture.
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Optional<unsigned> clang::getStackIndexOfNearestEnclosingCaptureCapableLambda(
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ArrayRef<const sema::FunctionScopeInfo *> FunctionScopes,
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VarDecl *VarToCapture, Sema &S) {
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const Optional<unsigned> NoLambdaIsCaptureCapable;
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const Optional<unsigned> OptionalStackIndex =
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getStackIndexOfNearestEnclosingCaptureReadyLambda(FunctionScopes,
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VarToCapture);
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if (!OptionalStackIndex)
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return NoLambdaIsCaptureCapable;
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const unsigned IndexOfCaptureReadyLambda = OptionalStackIndex.getValue();
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assert(((IndexOfCaptureReadyLambda != (FunctionScopes.size() - 1)) ||
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S.getCurGenericLambda()) &&
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"The capture ready lambda for a potential capture can only be the "
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"current lambda if it is a generic lambda");
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const sema::LambdaScopeInfo *const CaptureReadyLambdaLSI =
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cast<sema::LambdaScopeInfo>(FunctionScopes[IndexOfCaptureReadyLambda]);
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// If VarToCapture is null, we are attempting to capture 'this'
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const bool IsCapturingThis = !VarToCapture;
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const bool IsCapturingVariable = !IsCapturingThis;
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if (IsCapturingVariable) {
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// Check if the capture-ready lambda can truly capture the variable, by
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// checking whether all enclosing lambdas of the capture-ready lambda allow
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// the capture - i.e. make sure it is capture-capable.
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QualType CaptureType, DeclRefType;
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const bool CanCaptureVariable =
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!S.tryCaptureVariable(VarToCapture,
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/*ExprVarIsUsedInLoc*/ SourceLocation(),
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clang::Sema::TryCapture_Implicit,
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/*EllipsisLoc*/ SourceLocation(),
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/*BuildAndDiagnose*/ false, CaptureType,
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DeclRefType, &IndexOfCaptureReadyLambda);
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if (!CanCaptureVariable)
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return NoLambdaIsCaptureCapable;
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} else {
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// Check if the capture-ready lambda can truly capture 'this' by checking
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// whether all enclosing lambdas of the capture-ready lambda can capture
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// 'this'.
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const bool CanCaptureThis =
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!S.CheckCXXThisCapture(
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CaptureReadyLambdaLSI->PotentialThisCaptureLocation,
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/*Explicit*/ false, /*BuildAndDiagnose*/ false,
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&IndexOfCaptureReadyLambda);
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if (!CanCaptureThis)
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return NoLambdaIsCaptureCapable;
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}
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return IndexOfCaptureReadyLambda;
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}
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static inline TemplateParameterList *
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getGenericLambdaTemplateParameterList(LambdaScopeInfo *LSI, Sema &SemaRef) {
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if (!LSI->GLTemplateParameterList && !LSI->TemplateParams.empty()) {
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LSI->GLTemplateParameterList = TemplateParameterList::Create(
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SemaRef.Context,
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/*Template kw loc*/ SourceLocation(),
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/*L angle loc*/ LSI->ExplicitTemplateParamsRange.getBegin(),
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LSI->TemplateParams,
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/*R angle loc*/LSI->ExplicitTemplateParamsRange.getEnd(),
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LSI->RequiresClause.get());
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}
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return LSI->GLTemplateParameterList;
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}
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CXXRecordDecl *Sema::createLambdaClosureType(SourceRange IntroducerRange,
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TypeSourceInfo *Info,
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bool KnownDependent,
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LambdaCaptureDefault CaptureDefault) {
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DeclContext *DC = CurContext;
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while (!(DC->isFunctionOrMethod() || DC->isRecord() || DC->isFileContext()))
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DC = DC->getParent();
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bool IsGenericLambda = getGenericLambdaTemplateParameterList(getCurLambda(),
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*this);
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// Start constructing the lambda class.
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CXXRecordDecl *Class = CXXRecordDecl::CreateLambda(Context, DC, Info,
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IntroducerRange.getBegin(),
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KnownDependent,
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IsGenericLambda,
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CaptureDefault);
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DC->addDecl(Class);
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return Class;
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}
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/// Determine whether the given context is or is enclosed in an inline
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/// function.
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static bool isInInlineFunction(const DeclContext *DC) {
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while (!DC->isFileContext()) {
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if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(DC))
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if (FD->isInlined())
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return true;
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DC = DC->getLexicalParent();
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}
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return false;
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}
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std::tuple<MangleNumberingContext *, Decl *>
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Sema::getCurrentMangleNumberContext(const DeclContext *DC) {
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// Compute the context for allocating mangling numbers in the current
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// expression, if the ABI requires them.
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Decl *ManglingContextDecl = ExprEvalContexts.back().ManglingContextDecl;
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enum ContextKind {
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Normal,
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DefaultArgument,
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DataMember,
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StaticDataMember,
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InlineVariable,
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VariableTemplate
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} Kind = Normal;
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// Default arguments of member function parameters that appear in a class
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// definition, as well as the initializers of data members, receive special
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// treatment. Identify them.
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if (ManglingContextDecl) {
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if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(ManglingContextDecl)) {
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if (const DeclContext *LexicalDC
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= Param->getDeclContext()->getLexicalParent())
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if (LexicalDC->isRecord())
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Kind = DefaultArgument;
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} else if (VarDecl *Var = dyn_cast<VarDecl>(ManglingContextDecl)) {
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if (Var->getDeclContext()->isRecord())
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Kind = StaticDataMember;
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else if (Var->getMostRecentDecl()->isInline())
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Kind = InlineVariable;
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else if (Var->getDescribedVarTemplate())
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Kind = VariableTemplate;
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else if (auto *VTS = dyn_cast<VarTemplateSpecializationDecl>(Var)) {
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if (!VTS->isExplicitSpecialization())
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Kind = VariableTemplate;
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}
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} else if (isa<FieldDecl>(ManglingContextDecl)) {
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Kind = DataMember;
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}
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}
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// Itanium ABI [5.1.7]:
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// In the following contexts [...] the one-definition rule requires closure
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// types in different translation units to "correspond":
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bool IsInNonspecializedTemplate =
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inTemplateInstantiation() || CurContext->isDependentContext();
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switch (Kind) {
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case Normal: {
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// -- the bodies of non-exported nonspecialized template functions
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// -- the bodies of inline functions
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if ((IsInNonspecializedTemplate &&
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!(ManglingContextDecl && isa<ParmVarDecl>(ManglingContextDecl))) ||
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isInInlineFunction(CurContext)) {
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while (auto *CD = dyn_cast<CapturedDecl>(DC))
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DC = CD->getParent();
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return std::make_tuple(&Context.getManglingNumberContext(DC), nullptr);
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}
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return std::make_tuple(nullptr, nullptr);
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}
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case StaticDataMember:
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// -- the initializers of nonspecialized static members of template classes
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if (!IsInNonspecializedTemplate)
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return std::make_tuple(nullptr, ManglingContextDecl);
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// Fall through to get the current context.
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LLVM_FALLTHROUGH;
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case DataMember:
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// -- the in-class initializers of class members
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case DefaultArgument:
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// -- default arguments appearing in class definitions
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case InlineVariable:
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// -- the initializers of inline variables
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case VariableTemplate:
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// -- the initializers of templated variables
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return std::make_tuple(
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&Context.getManglingNumberContext(ASTContext::NeedExtraManglingDecl,
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ManglingContextDecl),
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ManglingContextDecl);
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}
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llvm_unreachable("unexpected context");
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}
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CXXMethodDecl *Sema::startLambdaDefinition(CXXRecordDecl *Class,
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SourceRange IntroducerRange,
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TypeSourceInfo *MethodTypeInfo,
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SourceLocation EndLoc,
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ArrayRef<ParmVarDecl *> Params,
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ConstexprSpecKind ConstexprKind,
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Expr *TrailingRequiresClause) {
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QualType MethodType = MethodTypeInfo->getType();
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TemplateParameterList *TemplateParams =
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getGenericLambdaTemplateParameterList(getCurLambda(), *this);
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// If a lambda appears in a dependent context or is a generic lambda (has
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// template parameters) and has an 'auto' return type, deduce it to a
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// dependent type.
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if (Class->isDependentContext() || TemplateParams) {
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const FunctionProtoType *FPT = MethodType->castAs<FunctionProtoType>();
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QualType Result = FPT->getReturnType();
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if (Result->isUndeducedType()) {
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Result = SubstAutoType(Result, Context.DependentTy);
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MethodType = Context.getFunctionType(Result, FPT->getParamTypes(),
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FPT->getExtProtoInfo());
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}
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}
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// C++11 [expr.prim.lambda]p5:
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// The closure type for a lambda-expression has a public inline function
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// call operator (13.5.4) whose parameters and return type are described by
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// the lambda-expression's parameter-declaration-clause and
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// trailing-return-type respectively.
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DeclarationName MethodName
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= Context.DeclarationNames.getCXXOperatorName(OO_Call);
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DeclarationNameLoc MethodNameLoc;
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MethodNameLoc.CXXOperatorName.BeginOpNameLoc
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= IntroducerRange.getBegin().getRawEncoding();
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MethodNameLoc.CXXOperatorName.EndOpNameLoc
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= IntroducerRange.getEnd().getRawEncoding();
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CXXMethodDecl *Method = CXXMethodDecl::Create(
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Context, Class, EndLoc,
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DeclarationNameInfo(MethodName, IntroducerRange.getBegin(),
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MethodNameLoc),
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MethodType, MethodTypeInfo, SC_None,
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/*isInline=*/true, ConstexprKind, EndLoc, TrailingRequiresClause);
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Method->setAccess(AS_public);
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if (!TemplateParams)
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Class->addDecl(Method);
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// Temporarily set the lexical declaration context to the current
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// context, so that the Scope stack matches the lexical nesting.
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Method->setLexicalDeclContext(CurContext);
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// Create a function template if we have a template parameter list
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FunctionTemplateDecl *const TemplateMethod = TemplateParams ?
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FunctionTemplateDecl::Create(Context, Class,
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Method->getLocation(), MethodName,
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TemplateParams,
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Method) : nullptr;
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if (TemplateMethod) {
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TemplateMethod->setAccess(AS_public);
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Method->setDescribedFunctionTemplate(TemplateMethod);
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Class->addDecl(TemplateMethod);
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TemplateMethod->setLexicalDeclContext(CurContext);
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}
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// Add parameters.
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if (!Params.empty()) {
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Method->setParams(Params);
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CheckParmsForFunctionDef(Params,
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/*CheckParameterNames=*/false);
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for (auto P : Method->parameters())
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P->setOwningFunction(Method);
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}
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return Method;
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}
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void Sema::handleLambdaNumbering(
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CXXRecordDecl *Class, CXXMethodDecl *Method,
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Optional<std::tuple<bool, unsigned, unsigned, Decl *>> Mangling) {
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if (Mangling) {
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bool HasKnownInternalLinkage;
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unsigned ManglingNumber, DeviceManglingNumber;
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Decl *ManglingContextDecl;
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std::tie(HasKnownInternalLinkage, ManglingNumber, DeviceManglingNumber,
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ManglingContextDecl) = Mangling.getValue();
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Class->setLambdaMangling(ManglingNumber, ManglingContextDecl,
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HasKnownInternalLinkage);
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Class->setDeviceLambdaManglingNumber(DeviceManglingNumber);
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return;
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}
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auto getMangleNumberingContext =
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[this](CXXRecordDecl *Class,
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Decl *ManglingContextDecl) -> MangleNumberingContext * {
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// Get mangle numbering context if there's any extra decl context.
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if (ManglingContextDecl)
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return &Context.getManglingNumberContext(
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ASTContext::NeedExtraManglingDecl, ManglingContextDecl);
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// Otherwise, from that lambda's decl context.
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auto DC = Class->getDeclContext();
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while (auto *CD = dyn_cast<CapturedDecl>(DC))
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DC = CD->getParent();
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return &Context.getManglingNumberContext(DC);
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};
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MangleNumberingContext *MCtx;
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Decl *ManglingContextDecl;
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std::tie(MCtx, ManglingContextDecl) =
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getCurrentMangleNumberContext(Class->getDeclContext());
|
|
bool HasKnownInternalLinkage = false;
|
|
if (!MCtx && getLangOpts().CUDA) {
|
|
// Force lambda numbering in CUDA/HIP as we need to name lambdas following
|
|
// ODR. Both device- and host-compilation need to have a consistent naming
|
|
// on kernel functions. As lambdas are potential part of these `__global__`
|
|
// function names, they needs numbering following ODR.
|
|
MCtx = getMangleNumberingContext(Class, ManglingContextDecl);
|
|
assert(MCtx && "Retrieving mangle numbering context failed!");
|
|
HasKnownInternalLinkage = true;
|
|
}
|
|
if (MCtx) {
|
|
unsigned ManglingNumber = MCtx->getManglingNumber(Method);
|
|
Class->setLambdaMangling(ManglingNumber, ManglingContextDecl,
|
|
HasKnownInternalLinkage);
|
|
Class->setDeviceLambdaManglingNumber(MCtx->getDeviceManglingNumber(Method));
|
|
}
|
|
}
|
|
|
|
void Sema::buildLambdaScope(LambdaScopeInfo *LSI,
|
|
CXXMethodDecl *CallOperator,
|
|
SourceRange IntroducerRange,
|
|
LambdaCaptureDefault CaptureDefault,
|
|
SourceLocation CaptureDefaultLoc,
|
|
bool ExplicitParams,
|
|
bool ExplicitResultType,
|
|
bool Mutable) {
|
|
LSI->CallOperator = CallOperator;
|
|
CXXRecordDecl *LambdaClass = CallOperator->getParent();
|
|
LSI->Lambda = LambdaClass;
|
|
if (CaptureDefault == LCD_ByCopy)
|
|
LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByval;
|
|
else if (CaptureDefault == LCD_ByRef)
|
|
LSI->ImpCaptureStyle = LambdaScopeInfo::ImpCap_LambdaByref;
|
|
LSI->CaptureDefaultLoc = CaptureDefaultLoc;
|
|
LSI->IntroducerRange = IntroducerRange;
|
|
LSI->ExplicitParams = ExplicitParams;
|
|
LSI->Mutable = Mutable;
|
|
|
|
if (ExplicitResultType) {
|
|
LSI->ReturnType = CallOperator->getReturnType();
|
|
|
|
if (!LSI->ReturnType->isDependentType() &&
|
|
!LSI->ReturnType->isVoidType()) {
|
|
if (RequireCompleteType(CallOperator->getBeginLoc(), LSI->ReturnType,
|
|
diag::err_lambda_incomplete_result)) {
|
|
// Do nothing.
|
|
}
|
|
}
|
|
} else {
|
|
LSI->HasImplicitReturnType = true;
|
|
}
|
|
}
|
|
|
|
void Sema::finishLambdaExplicitCaptures(LambdaScopeInfo *LSI) {
|
|
LSI->finishedExplicitCaptures();
|
|
}
|
|
|
|
void Sema::ActOnLambdaExplicitTemplateParameterList(SourceLocation LAngleLoc,
|
|
ArrayRef<NamedDecl *> TParams,
|
|
SourceLocation RAngleLoc,
|
|
ExprResult RequiresClause) {
|
|
LambdaScopeInfo *LSI = getCurLambda();
|
|
assert(LSI && "Expected a lambda scope");
|
|
assert(LSI->NumExplicitTemplateParams == 0 &&
|
|
"Already acted on explicit template parameters");
|
|
assert(LSI->TemplateParams.empty() &&
|
|
"Explicit template parameters should come "
|
|
"before invented (auto) ones");
|
|
assert(!TParams.empty() &&
|
|
"No template parameters to act on");
|
|
LSI->TemplateParams.append(TParams.begin(), TParams.end());
|
|
LSI->NumExplicitTemplateParams = TParams.size();
|
|
LSI->ExplicitTemplateParamsRange = {LAngleLoc, RAngleLoc};
|
|
LSI->RequiresClause = RequiresClause;
|
|
}
|
|
|
|
void Sema::addLambdaParameters(
|
|
ArrayRef<LambdaIntroducer::LambdaCapture> Captures,
|
|
CXXMethodDecl *CallOperator, Scope *CurScope) {
|
|
// Introduce our parameters into the function scope
|
|
for (unsigned p = 0, NumParams = CallOperator->getNumParams();
|
|
p < NumParams; ++p) {
|
|
ParmVarDecl *Param = CallOperator->getParamDecl(p);
|
|
|
|
// If this has an identifier, add it to the scope stack.
|
|
if (CurScope && Param->getIdentifier()) {
|
|
bool Error = false;
|
|
// Resolution of CWG 2211 in C++17 renders shadowing ill-formed, but we
|
|
// retroactively apply it.
|
|
for (const auto &Capture : Captures) {
|
|
if (Capture.Id == Param->getIdentifier()) {
|
|
Error = true;
|
|
Diag(Param->getLocation(), diag::err_parameter_shadow_capture);
|
|
Diag(Capture.Loc, diag::note_var_explicitly_captured_here)
|
|
<< Capture.Id << true;
|
|
}
|
|
}
|
|
if (!Error)
|
|
CheckShadow(CurScope, Param);
|
|
|
|
PushOnScopeChains(Param, CurScope);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// If this expression is an enumerator-like expression of some type
|
|
/// T, return the type T; otherwise, return null.
|
|
///
|
|
/// Pointer comparisons on the result here should always work because
|
|
/// it's derived from either the parent of an EnumConstantDecl
|
|
/// (i.e. the definition) or the declaration returned by
|
|
/// EnumType::getDecl() (i.e. the definition).
|
|
static EnumDecl *findEnumForBlockReturn(Expr *E) {
|
|
// An expression is an enumerator-like expression of type T if,
|
|
// ignoring parens and parens-like expressions:
|
|
E = E->IgnoreParens();
|
|
|
|
// - it is an enumerator whose enum type is T or
|
|
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
|
|
if (EnumConstantDecl *D
|
|
= dyn_cast<EnumConstantDecl>(DRE->getDecl())) {
|
|
return cast<EnumDecl>(D->getDeclContext());
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
// - it is a comma expression whose RHS is an enumerator-like
|
|
// expression of type T or
|
|
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
|
|
if (BO->getOpcode() == BO_Comma)
|
|
return findEnumForBlockReturn(BO->getRHS());
|
|
return nullptr;
|
|
}
|
|
|
|
// - it is a statement-expression whose value expression is an
|
|
// enumerator-like expression of type T or
|
|
if (StmtExpr *SE = dyn_cast<StmtExpr>(E)) {
|
|
if (Expr *last = dyn_cast_or_null<Expr>(SE->getSubStmt()->body_back()))
|
|
return findEnumForBlockReturn(last);
|
|
return nullptr;
|
|
}
|
|
|
|
// - it is a ternary conditional operator (not the GNU ?:
|
|
// extension) whose second and third operands are
|
|
// enumerator-like expressions of type T or
|
|
if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
|
|
if (EnumDecl *ED = findEnumForBlockReturn(CO->getTrueExpr()))
|
|
if (ED == findEnumForBlockReturn(CO->getFalseExpr()))
|
|
return ED;
|
|
return nullptr;
|
|
}
|
|
|
|
// (implicitly:)
|
|
// - it is an implicit integral conversion applied to an
|
|
// enumerator-like expression of type T or
|
|
if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
|
|
// We can sometimes see integral conversions in valid
|
|
// enumerator-like expressions.
|
|
if (ICE->getCastKind() == CK_IntegralCast)
|
|
return findEnumForBlockReturn(ICE->getSubExpr());
|
|
|
|
// Otherwise, just rely on the type.
|
|
}
|
|
|
|
// - it is an expression of that formal enum type.
|
|
if (const EnumType *ET = E->getType()->getAs<EnumType>()) {
|
|
return ET->getDecl();
|
|
}
|
|
|
|
// Otherwise, nope.
|
|
return nullptr;
|
|
}
|
|
|
|
/// Attempt to find a type T for which the returned expression of the
|
|
/// given statement is an enumerator-like expression of that type.
|
|
static EnumDecl *findEnumForBlockReturn(ReturnStmt *ret) {
|
|
if (Expr *retValue = ret->getRetValue())
|
|
return findEnumForBlockReturn(retValue);
|
|
return nullptr;
|
|
}
|
|
|
|
/// Attempt to find a common type T for which all of the returned
|
|
/// expressions in a block are enumerator-like expressions of that
|
|
/// type.
|
|
static EnumDecl *findCommonEnumForBlockReturns(ArrayRef<ReturnStmt*> returns) {
|
|
ArrayRef<ReturnStmt*>::iterator i = returns.begin(), e = returns.end();
|
|
|
|
// Try to find one for the first return.
|
|
EnumDecl *ED = findEnumForBlockReturn(*i);
|
|
if (!ED) return nullptr;
|
|
|
|
// Check that the rest of the returns have the same enum.
|
|
for (++i; i != e; ++i) {
|
|
if (findEnumForBlockReturn(*i) != ED)
|
|
return nullptr;
|
|
}
|
|
|
|
// Never infer an anonymous enum type.
|
|
if (!ED->hasNameForLinkage()) return nullptr;
|
|
|
|
return ED;
|
|
}
|
|
|
|
/// Adjust the given return statements so that they formally return
|
|
/// the given type. It should require, at most, an IntegralCast.
|
|
static void adjustBlockReturnsToEnum(Sema &S, ArrayRef<ReturnStmt*> returns,
|
|
QualType returnType) {
|
|
for (ArrayRef<ReturnStmt*>::iterator
|
|
i = returns.begin(), e = returns.end(); i != e; ++i) {
|
|
ReturnStmt *ret = *i;
|
|
Expr *retValue = ret->getRetValue();
|
|
if (S.Context.hasSameType(retValue->getType(), returnType))
|
|
continue;
|
|
|
|
// Right now we only support integral fixup casts.
|
|
assert(returnType->isIntegralOrUnscopedEnumerationType());
|
|
assert(retValue->getType()->isIntegralOrUnscopedEnumerationType());
|
|
|
|
ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(retValue);
|
|
|
|
Expr *E = (cleanups ? cleanups->getSubExpr() : retValue);
|
|
E = ImplicitCastExpr::Create(S.Context, returnType, CK_IntegralCast, E,
|
|
/*base path*/ nullptr, VK_RValue,
|
|
FPOptionsOverride());
|
|
if (cleanups) {
|
|
cleanups->setSubExpr(E);
|
|
} else {
|
|
ret->setRetValue(E);
|
|
}
|
|
}
|
|
}
|
|
|
|
void Sema::deduceClosureReturnType(CapturingScopeInfo &CSI) {
|
|
assert(CSI.HasImplicitReturnType);
|
|
// If it was ever a placeholder, it had to been deduced to DependentTy.
|
|
assert(CSI.ReturnType.isNull() || !CSI.ReturnType->isUndeducedType());
|
|
assert((!isa<LambdaScopeInfo>(CSI) || !getLangOpts().CPlusPlus14) &&
|
|
"lambda expressions use auto deduction in C++14 onwards");
|
|
|
|
// C++ core issue 975:
|
|
// If a lambda-expression does not include a trailing-return-type,
|
|
// it is as if the trailing-return-type denotes the following type:
|
|
// - if there are no return statements in the compound-statement,
|
|
// or all return statements return either an expression of type
|
|
// void or no expression or braced-init-list, the type void;
|
|
// - otherwise, if all return statements return an expression
|
|
// and the types of the returned expressions after
|
|
// lvalue-to-rvalue conversion (4.1 [conv.lval]),
|
|
// array-to-pointer conversion (4.2 [conv.array]), and
|
|
// function-to-pointer conversion (4.3 [conv.func]) are the
|
|
// same, that common type;
|
|
// - otherwise, the program is ill-formed.
|
|
//
|
|
// C++ core issue 1048 additionally removes top-level cv-qualifiers
|
|
// from the types of returned expressions to match the C++14 auto
|
|
// deduction rules.
|
|
//
|
|
// In addition, in blocks in non-C++ modes, if all of the return
|
|
// statements are enumerator-like expressions of some type T, where
|
|
// T has a name for linkage, then we infer the return type of the
|
|
// block to be that type.
|
|
|
|
// First case: no return statements, implicit void return type.
|
|
ASTContext &Ctx = getASTContext();
|
|
if (CSI.Returns.empty()) {
|
|
// It's possible there were simply no /valid/ return statements.
|
|
// In this case, the first one we found may have at least given us a type.
|
|
if (CSI.ReturnType.isNull())
|
|
CSI.ReturnType = Ctx.VoidTy;
|
|
return;
|
|
}
|
|
|
|
// Second case: at least one return statement has dependent type.
|
|
// Delay type checking until instantiation.
|
|
assert(!CSI.ReturnType.isNull() && "We should have a tentative return type.");
|
|
if (CSI.ReturnType->isDependentType())
|
|
return;
|
|
|
|
// Try to apply the enum-fuzz rule.
|
|
if (!getLangOpts().CPlusPlus) {
|
|
assert(isa<BlockScopeInfo>(CSI));
|
|
const EnumDecl *ED = findCommonEnumForBlockReturns(CSI.Returns);
|
|
if (ED) {
|
|
CSI.ReturnType = Context.getTypeDeclType(ED);
|
|
adjustBlockReturnsToEnum(*this, CSI.Returns, CSI.ReturnType);
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Third case: only one return statement. Don't bother doing extra work!
|
|
if (CSI.Returns.size() == 1)
|
|
return;
|
|
|
|
// General case: many return statements.
|
|
// Check that they all have compatible return types.
|
|
|
|
// We require the return types to strictly match here.
|
|
// Note that we've already done the required promotions as part of
|
|
// processing the return statement.
|
|
for (const ReturnStmt *RS : CSI.Returns) {
|
|
const Expr *RetE = RS->getRetValue();
|
|
|
|
QualType ReturnType =
|
|
(RetE ? RetE->getType() : Context.VoidTy).getUnqualifiedType();
|
|
if (Context.getCanonicalFunctionResultType(ReturnType) ==
|
|
Context.getCanonicalFunctionResultType(CSI.ReturnType)) {
|
|
// Use the return type with the strictest possible nullability annotation.
|
|
auto RetTyNullability = ReturnType->getNullability(Ctx);
|
|
auto BlockNullability = CSI.ReturnType->getNullability(Ctx);
|
|
if (BlockNullability &&
|
|
(!RetTyNullability ||
|
|
hasWeakerNullability(*RetTyNullability, *BlockNullability)))
|
|
CSI.ReturnType = ReturnType;
|
|
continue;
|
|
}
|
|
|
|
// FIXME: This is a poor diagnostic for ReturnStmts without expressions.
|
|
// TODO: It's possible that the *first* return is the divergent one.
|
|
Diag(RS->getBeginLoc(),
|
|
diag::err_typecheck_missing_return_type_incompatible)
|
|
<< ReturnType << CSI.ReturnType << isa<LambdaScopeInfo>(CSI);
|
|
// Continue iterating so that we keep emitting diagnostics.
|
|
}
|
|
}
|
|
|
|
QualType Sema::buildLambdaInitCaptureInitialization(
|
|
SourceLocation Loc, bool ByRef, SourceLocation EllipsisLoc,
|
|
Optional<unsigned> NumExpansions, IdentifierInfo *Id, bool IsDirectInit,
|
|
Expr *&Init) {
|
|
// Create an 'auto' or 'auto&' TypeSourceInfo that we can use to
|
|
// deduce against.
|
|
QualType DeductType = Context.getAutoDeductType();
|
|
TypeLocBuilder TLB;
|
|
AutoTypeLoc TL = TLB.push<AutoTypeLoc>(DeductType);
|
|
TL.setNameLoc(Loc);
|
|
if (ByRef) {
|
|
DeductType = BuildReferenceType(DeductType, true, Loc, Id);
|
|
assert(!DeductType.isNull() && "can't build reference to auto");
|
|
TLB.push<ReferenceTypeLoc>(DeductType).setSigilLoc(Loc);
|
|
}
|
|
if (EllipsisLoc.isValid()) {
|
|
if (Init->containsUnexpandedParameterPack()) {
|
|
Diag(EllipsisLoc, getLangOpts().CPlusPlus20
|
|
? diag::warn_cxx17_compat_init_capture_pack
|
|
: diag::ext_init_capture_pack);
|
|
DeductType = Context.getPackExpansionType(DeductType, NumExpansions,
|
|
/*ExpectPackInType=*/false);
|
|
TLB.push<PackExpansionTypeLoc>(DeductType).setEllipsisLoc(EllipsisLoc);
|
|
} else {
|
|
// Just ignore the ellipsis for now and form a non-pack variable. We'll
|
|
// diagnose this later when we try to capture it.
|
|
}
|
|
}
|
|
TypeSourceInfo *TSI = TLB.getTypeSourceInfo(Context, DeductType);
|
|
|
|
// Deduce the type of the init capture.
|
|
QualType DeducedType = deduceVarTypeFromInitializer(
|
|
/*VarDecl*/nullptr, DeclarationName(Id), DeductType, TSI,
|
|
SourceRange(Loc, Loc), IsDirectInit, Init);
|
|
if (DeducedType.isNull())
|
|
return QualType();
|
|
|
|
// Are we a non-list direct initialization?
|
|
ParenListExpr *CXXDirectInit = dyn_cast<ParenListExpr>(Init);
|
|
|
|
// Perform initialization analysis and ensure any implicit conversions
|
|
// (such as lvalue-to-rvalue) are enforced.
|
|
InitializedEntity Entity =
|
|
InitializedEntity::InitializeLambdaCapture(Id, DeducedType, Loc);
|
|
InitializationKind Kind =
|
|
IsDirectInit
|
|
? (CXXDirectInit ? InitializationKind::CreateDirect(
|
|
Loc, Init->getBeginLoc(), Init->getEndLoc())
|
|
: InitializationKind::CreateDirectList(Loc))
|
|
: InitializationKind::CreateCopy(Loc, Init->getBeginLoc());
|
|
|
|
MultiExprArg Args = Init;
|
|
if (CXXDirectInit)
|
|
Args =
|
|
MultiExprArg(CXXDirectInit->getExprs(), CXXDirectInit->getNumExprs());
|
|
QualType DclT;
|
|
InitializationSequence InitSeq(*this, Entity, Kind, Args);
|
|
ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Args, &DclT);
|
|
|
|
if (Result.isInvalid())
|
|
return QualType();
|
|
|
|
Init = Result.getAs<Expr>();
|
|
return DeducedType;
|
|
}
|
|
|
|
VarDecl *Sema::createLambdaInitCaptureVarDecl(SourceLocation Loc,
|
|
QualType InitCaptureType,
|
|
SourceLocation EllipsisLoc,
|
|
IdentifierInfo *Id,
|
|
unsigned InitStyle, Expr *Init) {
|
|
// FIXME: Retain the TypeSourceInfo from buildLambdaInitCaptureInitialization
|
|
// rather than reconstructing it here.
|
|
TypeSourceInfo *TSI = Context.getTrivialTypeSourceInfo(InitCaptureType, Loc);
|
|
if (auto PETL = TSI->getTypeLoc().getAs<PackExpansionTypeLoc>())
|
|
PETL.setEllipsisLoc(EllipsisLoc);
|
|
|
|
// Create a dummy variable representing the init-capture. This is not actually
|
|
// used as a variable, and only exists as a way to name and refer to the
|
|
// init-capture.
|
|
// FIXME: Pass in separate source locations for '&' and identifier.
|
|
VarDecl *NewVD = VarDecl::Create(Context, CurContext, Loc,
|
|
Loc, Id, InitCaptureType, TSI, SC_Auto);
|
|
NewVD->setInitCapture(true);
|
|
NewVD->setReferenced(true);
|
|
// FIXME: Pass in a VarDecl::InitializationStyle.
|
|
NewVD->setInitStyle(static_cast<VarDecl::InitializationStyle>(InitStyle));
|
|
NewVD->markUsed(Context);
|
|
NewVD->setInit(Init);
|
|
if (NewVD->isParameterPack())
|
|
getCurLambda()->LocalPacks.push_back(NewVD);
|
|
return NewVD;
|
|
}
|
|
|
|
void Sema::addInitCapture(LambdaScopeInfo *LSI, VarDecl *Var) {
|
|
assert(Var->isInitCapture() && "init capture flag should be set");
|
|
LSI->addCapture(Var, /*isBlock*/false, Var->getType()->isReferenceType(),
|
|
/*isNested*/false, Var->getLocation(), SourceLocation(),
|
|
Var->getType(), /*Invalid*/false);
|
|
}
|
|
|
|
void Sema::ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
|
|
Declarator &ParamInfo,
|
|
Scope *CurScope) {
|
|
LambdaScopeInfo *const LSI = getCurLambda();
|
|
assert(LSI && "LambdaScopeInfo should be on stack!");
|
|
|
|
// Determine if we're within a context where we know that the lambda will
|
|
// be dependent, because there are template parameters in scope.
|
|
bool KnownDependent;
|
|
if (LSI->NumExplicitTemplateParams > 0) {
|
|
auto *TemplateParamScope = CurScope->getTemplateParamParent();
|
|
assert(TemplateParamScope &&
|
|
"Lambda with explicit template param list should establish a "
|
|
"template param scope");
|
|
assert(TemplateParamScope->getParent());
|
|
KnownDependent = TemplateParamScope->getParent()
|
|
->getTemplateParamParent() != nullptr;
|
|
} else {
|
|
KnownDependent = CurScope->getTemplateParamParent() != nullptr;
|
|
}
|
|
|
|
// Determine the signature of the call operator.
|
|
TypeSourceInfo *MethodTyInfo;
|
|
bool ExplicitParams = true;
|
|
bool ExplicitResultType = true;
|
|
bool ContainsUnexpandedParameterPack = false;
|
|
SourceLocation EndLoc;
|
|
SmallVector<ParmVarDecl *, 8> Params;
|
|
if (ParamInfo.getNumTypeObjects() == 0) {
|
|
// C++11 [expr.prim.lambda]p4:
|
|
// If a lambda-expression does not include a lambda-declarator, it is as
|
|
// if the lambda-declarator were ().
|
|
FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
|
|
/*IsVariadic=*/false, /*IsCXXMethod=*/true));
|
|
EPI.HasTrailingReturn = true;
|
|
EPI.TypeQuals.addConst();
|
|
LangAS AS = getDefaultCXXMethodAddrSpace();
|
|
if (AS != LangAS::Default)
|
|
EPI.TypeQuals.addAddressSpace(AS);
|
|
|
|
// C++1y [expr.prim.lambda]:
|
|
// The lambda return type is 'auto', which is replaced by the
|
|
// trailing-return type if provided and/or deduced from 'return'
|
|
// statements
|
|
// We don't do this before C++1y, because we don't support deduced return
|
|
// types there.
|
|
QualType DefaultTypeForNoTrailingReturn =
|
|
getLangOpts().CPlusPlus14 ? Context.getAutoDeductType()
|
|
: Context.DependentTy;
|
|
QualType MethodTy =
|
|
Context.getFunctionType(DefaultTypeForNoTrailingReturn, None, EPI);
|
|
MethodTyInfo = Context.getTrivialTypeSourceInfo(MethodTy);
|
|
ExplicitParams = false;
|
|
ExplicitResultType = false;
|
|
EndLoc = Intro.Range.getEnd();
|
|
} else {
|
|
assert(ParamInfo.isFunctionDeclarator() &&
|
|
"lambda-declarator is a function");
|
|
DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getFunctionTypeInfo();
|
|
|
|
// C++11 [expr.prim.lambda]p5:
|
|
// This function call operator is declared const (9.3.1) if and only if
|
|
// the lambda-expression's parameter-declaration-clause is not followed
|
|
// by mutable. It is neither virtual nor declared volatile. [...]
|
|
if (!FTI.hasMutableQualifier()) {
|
|
FTI.getOrCreateMethodQualifiers().SetTypeQual(DeclSpec::TQ_const,
|
|
SourceLocation());
|
|
}
|
|
|
|
MethodTyInfo = GetTypeForDeclarator(ParamInfo, CurScope);
|
|
assert(MethodTyInfo && "no type from lambda-declarator");
|
|
EndLoc = ParamInfo.getSourceRange().getEnd();
|
|
|
|
ExplicitResultType = FTI.hasTrailingReturnType();
|
|
|
|
if (FTIHasNonVoidParameters(FTI)) {
|
|
Params.reserve(FTI.NumParams);
|
|
for (unsigned i = 0, e = FTI.NumParams; i != e; ++i)
|
|
Params.push_back(cast<ParmVarDecl>(FTI.Params[i].Param));
|
|
}
|
|
|
|
// Check for unexpanded parameter packs in the method type.
|
|
if (MethodTyInfo->getType()->containsUnexpandedParameterPack())
|
|
DiagnoseUnexpandedParameterPack(Intro.Range.getBegin(), MethodTyInfo,
|
|
UPPC_DeclarationType);
|
|
}
|
|
|
|
CXXRecordDecl *Class = createLambdaClosureType(Intro.Range, MethodTyInfo,
|
|
KnownDependent, Intro.Default);
|
|
CXXMethodDecl *Method =
|
|
startLambdaDefinition(Class, Intro.Range, MethodTyInfo, EndLoc, Params,
|
|
ParamInfo.getDeclSpec().getConstexprSpecifier(),
|
|
ParamInfo.getTrailingRequiresClause());
|
|
if (ExplicitParams)
|
|
CheckCXXDefaultArguments(Method);
|
|
|
|
// This represents the function body for the lambda function, check if we
|
|
// have to apply optnone due to a pragma.
|
|
AddRangeBasedOptnone(Method);
|
|
|
|
// code_seg attribute on lambda apply to the method.
|
|
if (Attr *A = getImplicitCodeSegOrSectionAttrForFunction(Method, /*IsDefinition=*/true))
|
|
Method->addAttr(A);
|
|
|
|
// Attributes on the lambda apply to the method.
|
|
ProcessDeclAttributes(CurScope, Method, ParamInfo);
|
|
|
|
// CUDA lambdas get implicit host and device attributes.
|
|
if (getLangOpts().CUDA)
|
|
CUDASetLambdaAttrs(Method);
|
|
|
|
// OpenMP lambdas might get assumumption attributes.
|
|
if (LangOpts.OpenMP)
|
|
ActOnFinishedFunctionDefinitionInOpenMPAssumeScope(Method);
|
|
|
|
// Number the lambda for linkage purposes if necessary.
|
|
handleLambdaNumbering(Class, Method);
|
|
|
|
// Introduce the function call operator as the current declaration context.
|
|
PushDeclContext(CurScope, Method);
|
|
|
|
// Build the lambda scope.
|
|
buildLambdaScope(LSI, Method, Intro.Range, Intro.Default, Intro.DefaultLoc,
|
|
ExplicitParams, ExplicitResultType, !Method->isConst());
|
|
|
|
// C++11 [expr.prim.lambda]p9:
|
|
// A lambda-expression whose smallest enclosing scope is a block scope is a
|
|
// local lambda expression; any other lambda expression shall not have a
|
|
// capture-default or simple-capture in its lambda-introducer.
|
|
//
|
|
// For simple-captures, this is covered by the check below that any named
|
|
// entity is a variable that can be captured.
|
|
//
|
|
// For DR1632, we also allow a capture-default in any context where we can
|
|
// odr-use 'this' (in particular, in a default initializer for a non-static
|
|
// data member).
|
|
if (Intro.Default != LCD_None && !Class->getParent()->isFunctionOrMethod() &&
|
|
(getCurrentThisType().isNull() ||
|
|
CheckCXXThisCapture(SourceLocation(), /*Explicit*/true,
|
|
/*BuildAndDiagnose*/false)))
|
|
Diag(Intro.DefaultLoc, diag::err_capture_default_non_local);
|
|
|
|
// Distinct capture names, for diagnostics.
|
|
llvm::SmallSet<IdentifierInfo*, 8> CaptureNames;
|
|
|
|
// Handle explicit captures.
|
|
SourceLocation PrevCaptureLoc
|
|
= Intro.Default == LCD_None? Intro.Range.getBegin() : Intro.DefaultLoc;
|
|
for (auto C = Intro.Captures.begin(), E = Intro.Captures.end(); C != E;
|
|
PrevCaptureLoc = C->Loc, ++C) {
|
|
if (C->Kind == LCK_This || C->Kind == LCK_StarThis) {
|
|
if (C->Kind == LCK_StarThis)
|
|
Diag(C->Loc, !getLangOpts().CPlusPlus17
|
|
? diag::ext_star_this_lambda_capture_cxx17
|
|
: diag::warn_cxx14_compat_star_this_lambda_capture);
|
|
|
|
// C++11 [expr.prim.lambda]p8:
|
|
// An identifier or this shall not appear more than once in a
|
|
// lambda-capture.
|
|
if (LSI->isCXXThisCaptured()) {
|
|
Diag(C->Loc, diag::err_capture_more_than_once)
|
|
<< "'this'" << SourceRange(LSI->getCXXThisCapture().getLocation())
|
|
<< FixItHint::CreateRemoval(
|
|
SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
|
|
continue;
|
|
}
|
|
|
|
// C++2a [expr.prim.lambda]p8:
|
|
// If a lambda-capture includes a capture-default that is =,
|
|
// each simple-capture of that lambda-capture shall be of the form
|
|
// "&identifier", "this", or "* this". [ Note: The form [&,this] is
|
|
// redundant but accepted for compatibility with ISO C++14. --end note ]
|
|
if (Intro.Default == LCD_ByCopy && C->Kind != LCK_StarThis)
|
|
Diag(C->Loc, !getLangOpts().CPlusPlus20
|
|
? diag::ext_equals_this_lambda_capture_cxx20
|
|
: diag::warn_cxx17_compat_equals_this_lambda_capture);
|
|
|
|
// C++11 [expr.prim.lambda]p12:
|
|
// If this is captured by a local lambda expression, its nearest
|
|
// enclosing function shall be a non-static member function.
|
|
QualType ThisCaptureType = getCurrentThisType();
|
|
if (ThisCaptureType.isNull()) {
|
|
Diag(C->Loc, diag::err_this_capture) << true;
|
|
continue;
|
|
}
|
|
|
|
CheckCXXThisCapture(C->Loc, /*Explicit=*/true, /*BuildAndDiagnose*/ true,
|
|
/*FunctionScopeIndexToStopAtPtr*/ nullptr,
|
|
C->Kind == LCK_StarThis);
|
|
if (!LSI->Captures.empty())
|
|
LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange;
|
|
continue;
|
|
}
|
|
|
|
assert(C->Id && "missing identifier for capture");
|
|
|
|
if (C->Init.isInvalid())
|
|
continue;
|
|
|
|
VarDecl *Var = nullptr;
|
|
if (C->Init.isUsable()) {
|
|
Diag(C->Loc, getLangOpts().CPlusPlus14
|
|
? diag::warn_cxx11_compat_init_capture
|
|
: diag::ext_init_capture);
|
|
|
|
// If the initializer expression is usable, but the InitCaptureType
|
|
// is not, then an error has occurred - so ignore the capture for now.
|
|
// for e.g., [n{0}] { }; <-- if no <initializer_list> is included.
|
|
// FIXME: we should create the init capture variable and mark it invalid
|
|
// in this case.
|
|
if (C->InitCaptureType.get().isNull())
|
|
continue;
|
|
|
|
if (C->Init.get()->containsUnexpandedParameterPack() &&
|
|
!C->InitCaptureType.get()->getAs<PackExpansionType>())
|
|
DiagnoseUnexpandedParameterPack(C->Init.get(), UPPC_Initializer);
|
|
|
|
unsigned InitStyle;
|
|
switch (C->InitKind) {
|
|
case LambdaCaptureInitKind::NoInit:
|
|
llvm_unreachable("not an init-capture?");
|
|
case LambdaCaptureInitKind::CopyInit:
|
|
InitStyle = VarDecl::CInit;
|
|
break;
|
|
case LambdaCaptureInitKind::DirectInit:
|
|
InitStyle = VarDecl::CallInit;
|
|
break;
|
|
case LambdaCaptureInitKind::ListInit:
|
|
InitStyle = VarDecl::ListInit;
|
|
break;
|
|
}
|
|
Var = createLambdaInitCaptureVarDecl(C->Loc, C->InitCaptureType.get(),
|
|
C->EllipsisLoc, C->Id, InitStyle,
|
|
C->Init.get());
|
|
// C++1y [expr.prim.lambda]p11:
|
|
// An init-capture behaves as if it declares and explicitly
|
|
// captures a variable [...] whose declarative region is the
|
|
// lambda-expression's compound-statement
|
|
if (Var)
|
|
PushOnScopeChains(Var, CurScope, false);
|
|
} else {
|
|
assert(C->InitKind == LambdaCaptureInitKind::NoInit &&
|
|
"init capture has valid but null init?");
|
|
|
|
// C++11 [expr.prim.lambda]p8:
|
|
// If a lambda-capture includes a capture-default that is &, the
|
|
// identifiers in the lambda-capture shall not be preceded by &.
|
|
// If a lambda-capture includes a capture-default that is =, [...]
|
|
// each identifier it contains shall be preceded by &.
|
|
if (C->Kind == LCK_ByRef && Intro.Default == LCD_ByRef) {
|
|
Diag(C->Loc, diag::err_reference_capture_with_reference_default)
|
|
<< FixItHint::CreateRemoval(
|
|
SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
|
|
continue;
|
|
} else if (C->Kind == LCK_ByCopy && Intro.Default == LCD_ByCopy) {
|
|
Diag(C->Loc, diag::err_copy_capture_with_copy_default)
|
|
<< FixItHint::CreateRemoval(
|
|
SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
|
|
continue;
|
|
}
|
|
|
|
// C++11 [expr.prim.lambda]p10:
|
|
// The identifiers in a capture-list are looked up using the usual
|
|
// rules for unqualified name lookup (3.4.1)
|
|
DeclarationNameInfo Name(C->Id, C->Loc);
|
|
LookupResult R(*this, Name, LookupOrdinaryName);
|
|
LookupName(R, CurScope);
|
|
if (R.isAmbiguous())
|
|
continue;
|
|
if (R.empty()) {
|
|
// FIXME: Disable corrections that would add qualification?
|
|
CXXScopeSpec ScopeSpec;
|
|
DeclFilterCCC<VarDecl> Validator{};
|
|
if (DiagnoseEmptyLookup(CurScope, ScopeSpec, R, Validator))
|
|
continue;
|
|
}
|
|
|
|
Var = R.getAsSingle<VarDecl>();
|
|
if (Var && DiagnoseUseOfDecl(Var, C->Loc))
|
|
continue;
|
|
}
|
|
|
|
// C++11 [expr.prim.lambda]p8:
|
|
// An identifier or this shall not appear more than once in a
|
|
// lambda-capture.
|
|
if (!CaptureNames.insert(C->Id).second) {
|
|
if (Var && LSI->isCaptured(Var)) {
|
|
Diag(C->Loc, diag::err_capture_more_than_once)
|
|
<< C->Id << SourceRange(LSI->getCapture(Var).getLocation())
|
|
<< FixItHint::CreateRemoval(
|
|
SourceRange(getLocForEndOfToken(PrevCaptureLoc), C->Loc));
|
|
} else
|
|
// Previous capture captured something different (one or both was
|
|
// an init-cpature): no fixit.
|
|
Diag(C->Loc, diag::err_capture_more_than_once) << C->Id;
|
|
continue;
|
|
}
|
|
|
|
// C++11 [expr.prim.lambda]p10:
|
|
// [...] each such lookup shall find a variable with automatic storage
|
|
// duration declared in the reaching scope of the local lambda expression.
|
|
// Note that the 'reaching scope' check happens in tryCaptureVariable().
|
|
if (!Var) {
|
|
Diag(C->Loc, diag::err_capture_does_not_name_variable) << C->Id;
|
|
continue;
|
|
}
|
|
|
|
// Ignore invalid decls; they'll just confuse the code later.
|
|
if (Var->isInvalidDecl())
|
|
continue;
|
|
|
|
if (!Var->hasLocalStorage()) {
|
|
Diag(C->Loc, diag::err_capture_non_automatic_variable) << C->Id;
|
|
Diag(Var->getLocation(), diag::note_previous_decl) << C->Id;
|
|
continue;
|
|
}
|
|
|
|
// C++11 [expr.prim.lambda]p23:
|
|
// A capture followed by an ellipsis is a pack expansion (14.5.3).
|
|
SourceLocation EllipsisLoc;
|
|
if (C->EllipsisLoc.isValid()) {
|
|
if (Var->isParameterPack()) {
|
|
EllipsisLoc = C->EllipsisLoc;
|
|
} else {
|
|
Diag(C->EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
|
|
<< (C->Init.isUsable() ? C->Init.get()->getSourceRange()
|
|
: SourceRange(C->Loc));
|
|
|
|
// Just ignore the ellipsis.
|
|
}
|
|
} else if (Var->isParameterPack()) {
|
|
ContainsUnexpandedParameterPack = true;
|
|
}
|
|
|
|
if (C->Init.isUsable()) {
|
|
addInitCapture(LSI, Var);
|
|
} else {
|
|
TryCaptureKind Kind = C->Kind == LCK_ByRef ? TryCapture_ExplicitByRef :
|
|
TryCapture_ExplicitByVal;
|
|
tryCaptureVariable(Var, C->Loc, Kind, EllipsisLoc);
|
|
}
|
|
if (!LSI->Captures.empty())
|
|
LSI->ExplicitCaptureRanges[LSI->Captures.size() - 1] = C->ExplicitRange;
|
|
}
|
|
finishLambdaExplicitCaptures(LSI);
|
|
|
|
LSI->ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack;
|
|
|
|
// Add lambda parameters into scope.
|
|
addLambdaParameters(Intro.Captures, Method, CurScope);
|
|
|
|
// Enter a new evaluation context to insulate the lambda from any
|
|
// cleanups from the enclosing full-expression.
|
|
PushExpressionEvaluationContext(
|
|
LSI->CallOperator->isConsteval()
|
|
? ExpressionEvaluationContext::ConstantEvaluated
|
|
: ExpressionEvaluationContext::PotentiallyEvaluated);
|
|
}
|
|
|
|
void Sema::ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope,
|
|
bool IsInstantiation) {
|
|
LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(FunctionScopes.back());
|
|
|
|
// Leave the expression-evaluation context.
|
|
DiscardCleanupsInEvaluationContext();
|
|
PopExpressionEvaluationContext();
|
|
|
|
// Leave the context of the lambda.
|
|
if (!IsInstantiation)
|
|
PopDeclContext();
|
|
|
|
// Finalize the lambda.
|
|
CXXRecordDecl *Class = LSI->Lambda;
|
|
Class->setInvalidDecl();
|
|
SmallVector<Decl*, 4> Fields(Class->fields());
|
|
ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
|
|
SourceLocation(), ParsedAttributesView());
|
|
CheckCompletedCXXClass(nullptr, Class);
|
|
|
|
PopFunctionScopeInfo();
|
|
}
|
|
|
|
template <typename Func>
|
|
static void repeatForLambdaConversionFunctionCallingConvs(
|
|
Sema &S, const FunctionProtoType &CallOpProto, Func F) {
|
|
CallingConv DefaultFree = S.Context.getDefaultCallingConvention(
|
|
CallOpProto.isVariadic(), /*IsCXXMethod=*/false);
|
|
CallingConv DefaultMember = S.Context.getDefaultCallingConvention(
|
|
CallOpProto.isVariadic(), /*IsCXXMethod=*/true);
|
|
CallingConv CallOpCC = CallOpProto.getCallConv();
|
|
|
|
/// Implement emitting a version of the operator for many of the calling
|
|
/// conventions for MSVC, as described here:
|
|
/// https://devblogs.microsoft.com/oldnewthing/20150220-00/?p=44623.
|
|
/// Experimentally, we determined that cdecl, stdcall, fastcall, and
|
|
/// vectorcall are generated by MSVC when it is supported by the target.
|
|
/// Additionally, we are ensuring that the default-free/default-member and
|
|
/// call-operator calling convention are generated as well.
|
|
/// NOTE: We intentionally generate a 'thiscall' on Win32 implicitly from the
|
|
/// 'member default', despite MSVC not doing so. We do this in order to ensure
|
|
/// that someone who intentionally places 'thiscall' on the lambda call
|
|
/// operator will still get that overload, since we don't have the a way of
|
|
/// detecting the attribute by the time we get here.
|
|
if (S.getLangOpts().MSVCCompat) {
|
|
CallingConv Convs[] = {
|
|
CC_C, CC_X86StdCall, CC_X86FastCall, CC_X86VectorCall,
|
|
DefaultFree, DefaultMember, CallOpCC};
|
|
llvm::sort(Convs);
|
|
llvm::iterator_range<CallingConv *> Range(
|
|
std::begin(Convs), std::unique(std::begin(Convs), std::end(Convs)));
|
|
const TargetInfo &TI = S.getASTContext().getTargetInfo();
|
|
|
|
for (CallingConv C : Range) {
|
|
if (TI.checkCallingConvention(C) == TargetInfo::CCCR_OK)
|
|
F(C);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (CallOpCC == DefaultMember && DefaultMember != DefaultFree) {
|
|
F(DefaultFree);
|
|
F(DefaultMember);
|
|
} else {
|
|
F(CallOpCC);
|
|
}
|
|
}
|
|
|
|
// Returns the 'standard' calling convention to be used for the lambda
|
|
// conversion function, that is, the 'free' function calling convention unless
|
|
// it is overridden by a non-default calling convention attribute.
|
|
static CallingConv
|
|
getLambdaConversionFunctionCallConv(Sema &S,
|
|
const FunctionProtoType *CallOpProto) {
|
|
CallingConv DefaultFree = S.Context.getDefaultCallingConvention(
|
|
CallOpProto->isVariadic(), /*IsCXXMethod=*/false);
|
|
CallingConv DefaultMember = S.Context.getDefaultCallingConvention(
|
|
CallOpProto->isVariadic(), /*IsCXXMethod=*/true);
|
|
CallingConv CallOpCC = CallOpProto->getCallConv();
|
|
|
|
// If the call-operator hasn't been changed, return both the 'free' and
|
|
// 'member' function calling convention.
|
|
if (CallOpCC == DefaultMember && DefaultMember != DefaultFree)
|
|
return DefaultFree;
|
|
return CallOpCC;
|
|
}
|
|
|
|
QualType Sema::getLambdaConversionFunctionResultType(
|
|
const FunctionProtoType *CallOpProto, CallingConv CC) {
|
|
const FunctionProtoType::ExtProtoInfo CallOpExtInfo =
|
|
CallOpProto->getExtProtoInfo();
|
|
FunctionProtoType::ExtProtoInfo InvokerExtInfo = CallOpExtInfo;
|
|
InvokerExtInfo.ExtInfo = InvokerExtInfo.ExtInfo.withCallingConv(CC);
|
|
InvokerExtInfo.TypeQuals = Qualifiers();
|
|
assert(InvokerExtInfo.RefQualifier == RQ_None &&
|
|
"Lambda's call operator should not have a reference qualifier");
|
|
return Context.getFunctionType(CallOpProto->getReturnType(),
|
|
CallOpProto->getParamTypes(), InvokerExtInfo);
|
|
}
|
|
|
|
/// Add a lambda's conversion to function pointer, as described in
|
|
/// C++11 [expr.prim.lambda]p6.
|
|
static void addFunctionPointerConversion(Sema &S, SourceRange IntroducerRange,
|
|
CXXRecordDecl *Class,
|
|
CXXMethodDecl *CallOperator,
|
|
QualType InvokerFunctionTy) {
|
|
// This conversion is explicitly disabled if the lambda's function has
|
|
// pass_object_size attributes on any of its parameters.
|
|
auto HasPassObjectSizeAttr = [](const ParmVarDecl *P) {
|
|
return P->hasAttr<PassObjectSizeAttr>();
|
|
};
|
|
if (llvm::any_of(CallOperator->parameters(), HasPassObjectSizeAttr))
|
|
return;
|
|
|
|
// Add the conversion to function pointer.
|
|
QualType PtrToFunctionTy = S.Context.getPointerType(InvokerFunctionTy);
|
|
|
|
// Create the type of the conversion function.
|
|
FunctionProtoType::ExtProtoInfo ConvExtInfo(
|
|
S.Context.getDefaultCallingConvention(
|
|
/*IsVariadic=*/false, /*IsCXXMethod=*/true));
|
|
// The conversion function is always const and noexcept.
|
|
ConvExtInfo.TypeQuals = Qualifiers();
|
|
ConvExtInfo.TypeQuals.addConst();
|
|
ConvExtInfo.ExceptionSpec.Type = EST_BasicNoexcept;
|
|
QualType ConvTy =
|
|
S.Context.getFunctionType(PtrToFunctionTy, None, ConvExtInfo);
|
|
|
|
SourceLocation Loc = IntroducerRange.getBegin();
|
|
DeclarationName ConversionName
|
|
= S.Context.DeclarationNames.getCXXConversionFunctionName(
|
|
S.Context.getCanonicalType(PtrToFunctionTy));
|
|
DeclarationNameLoc ConvNameLoc;
|
|
// Construct a TypeSourceInfo for the conversion function, and wire
|
|
// all the parameters appropriately for the FunctionProtoTypeLoc
|
|
// so that everything works during transformation/instantiation of
|
|
// generic lambdas.
|
|
// The main reason for wiring up the parameters of the conversion
|
|
// function with that of the call operator is so that constructs
|
|
// like the following work:
|
|
// auto L = [](auto b) { <-- 1
|
|
// return [](auto a) -> decltype(a) { <-- 2
|
|
// return a;
|
|
// };
|
|
// };
|
|
// int (*fp)(int) = L(5);
|
|
// Because the trailing return type can contain DeclRefExprs that refer
|
|
// to the original call operator's variables, we hijack the call
|
|
// operators ParmVarDecls below.
|
|
TypeSourceInfo *ConvNamePtrToFunctionTSI =
|
|
S.Context.getTrivialTypeSourceInfo(PtrToFunctionTy, Loc);
|
|
ConvNameLoc.NamedType.TInfo = ConvNamePtrToFunctionTSI;
|
|
|
|
// The conversion function is a conversion to a pointer-to-function.
|
|
TypeSourceInfo *ConvTSI = S.Context.getTrivialTypeSourceInfo(ConvTy, Loc);
|
|
FunctionProtoTypeLoc ConvTL =
|
|
ConvTSI->getTypeLoc().getAs<FunctionProtoTypeLoc>();
|
|
// Get the result of the conversion function which is a pointer-to-function.
|
|
PointerTypeLoc PtrToFunctionTL =
|
|
ConvTL.getReturnLoc().getAs<PointerTypeLoc>();
|
|
// Do the same for the TypeSourceInfo that is used to name the conversion
|
|
// operator.
|
|
PointerTypeLoc ConvNamePtrToFunctionTL =
|
|
ConvNamePtrToFunctionTSI->getTypeLoc().getAs<PointerTypeLoc>();
|
|
|
|
// Get the underlying function types that the conversion function will
|
|
// be converting to (should match the type of the call operator).
|
|
FunctionProtoTypeLoc CallOpConvTL =
|
|
PtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
|
|
FunctionProtoTypeLoc CallOpConvNameTL =
|
|
ConvNamePtrToFunctionTL.getPointeeLoc().getAs<FunctionProtoTypeLoc>();
|
|
|
|
// Wire up the FunctionProtoTypeLocs with the call operator's parameters.
|
|
// These parameter's are essentially used to transform the name and
|
|
// the type of the conversion operator. By using the same parameters
|
|
// as the call operator's we don't have to fix any back references that
|
|
// the trailing return type of the call operator's uses (such as
|
|
// decltype(some_type<decltype(a)>::type{} + decltype(a){}) etc.)
|
|
// - we can simply use the return type of the call operator, and
|
|
// everything should work.
|
|
SmallVector<ParmVarDecl *, 4> InvokerParams;
|
|
for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I) {
|
|
ParmVarDecl *From = CallOperator->getParamDecl(I);
|
|
|
|
InvokerParams.push_back(ParmVarDecl::Create(
|
|
S.Context,
|
|
// Temporarily add to the TU. This is set to the invoker below.
|
|
S.Context.getTranslationUnitDecl(), From->getBeginLoc(),
|
|
From->getLocation(), From->getIdentifier(), From->getType(),
|
|
From->getTypeSourceInfo(), From->getStorageClass(),
|
|
/*DefArg=*/nullptr));
|
|
CallOpConvTL.setParam(I, From);
|
|
CallOpConvNameTL.setParam(I, From);
|
|
}
|
|
|
|
CXXConversionDecl *Conversion = CXXConversionDecl::Create(
|
|
S.Context, Class, Loc,
|
|
DeclarationNameInfo(ConversionName, Loc, ConvNameLoc), ConvTy, ConvTSI,
|
|
/*isInline=*/true, ExplicitSpecifier(),
|
|
S.getLangOpts().CPlusPlus17 ? ConstexprSpecKind::Constexpr
|
|
: ConstexprSpecKind::Unspecified,
|
|
CallOperator->getBody()->getEndLoc());
|
|
Conversion->setAccess(AS_public);
|
|
Conversion->setImplicit(true);
|
|
|
|
if (Class->isGenericLambda()) {
|
|
// Create a template version of the conversion operator, using the template
|
|
// parameter list of the function call operator.
|
|
FunctionTemplateDecl *TemplateCallOperator =
|
|
CallOperator->getDescribedFunctionTemplate();
|
|
FunctionTemplateDecl *ConversionTemplate =
|
|
FunctionTemplateDecl::Create(S.Context, Class,
|
|
Loc, ConversionName,
|
|
TemplateCallOperator->getTemplateParameters(),
|
|
Conversion);
|
|
ConversionTemplate->setAccess(AS_public);
|
|
ConversionTemplate->setImplicit(true);
|
|
Conversion->setDescribedFunctionTemplate(ConversionTemplate);
|
|
Class->addDecl(ConversionTemplate);
|
|
} else
|
|
Class->addDecl(Conversion);
|
|
// Add a non-static member function that will be the result of
|
|
// the conversion with a certain unique ID.
|
|
DeclarationName InvokerName = &S.Context.Idents.get(
|
|
getLambdaStaticInvokerName());
|
|
// FIXME: Instead of passing in the CallOperator->getTypeSourceInfo()
|
|
// we should get a prebuilt TrivialTypeSourceInfo from Context
|
|
// using FunctionTy & Loc and get its TypeLoc as a FunctionProtoTypeLoc
|
|
// then rewire the parameters accordingly, by hoisting up the InvokeParams
|
|
// loop below and then use its Params to set Invoke->setParams(...) below.
|
|
// This would avoid the 'const' qualifier of the calloperator from
|
|
// contaminating the type of the invoker, which is currently adjusted
|
|
// in SemaTemplateDeduction.cpp:DeduceTemplateArguments. Fixing the
|
|
// trailing return type of the invoker would require a visitor to rebuild
|
|
// the trailing return type and adjusting all back DeclRefExpr's to refer
|
|
// to the new static invoker parameters - not the call operator's.
|
|
CXXMethodDecl *Invoke = CXXMethodDecl::Create(
|
|
S.Context, Class, Loc, DeclarationNameInfo(InvokerName, Loc),
|
|
InvokerFunctionTy, CallOperator->getTypeSourceInfo(), SC_Static,
|
|
/*isInline=*/true, ConstexprSpecKind::Unspecified,
|
|
CallOperator->getBody()->getEndLoc());
|
|
for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I)
|
|
InvokerParams[I]->setOwningFunction(Invoke);
|
|
Invoke->setParams(InvokerParams);
|
|
Invoke->setAccess(AS_private);
|
|
Invoke->setImplicit(true);
|
|
if (Class->isGenericLambda()) {
|
|
FunctionTemplateDecl *TemplateCallOperator =
|
|
CallOperator->getDescribedFunctionTemplate();
|
|
FunctionTemplateDecl *StaticInvokerTemplate = FunctionTemplateDecl::Create(
|
|
S.Context, Class, Loc, InvokerName,
|
|
TemplateCallOperator->getTemplateParameters(),
|
|
Invoke);
|
|
StaticInvokerTemplate->setAccess(AS_private);
|
|
StaticInvokerTemplate->setImplicit(true);
|
|
Invoke->setDescribedFunctionTemplate(StaticInvokerTemplate);
|
|
Class->addDecl(StaticInvokerTemplate);
|
|
} else
|
|
Class->addDecl(Invoke);
|
|
}
|
|
|
|
/// Add a lambda's conversion to function pointers, as described in
|
|
/// C++11 [expr.prim.lambda]p6. Note that in most cases, this should emit only a
|
|
/// single pointer conversion. In the event that the default calling convention
|
|
/// for free and member functions is different, it will emit both conventions.
|
|
static void addFunctionPointerConversions(Sema &S, SourceRange IntroducerRange,
|
|
CXXRecordDecl *Class,
|
|
CXXMethodDecl *CallOperator) {
|
|
const FunctionProtoType *CallOpProto =
|
|
CallOperator->getType()->castAs<FunctionProtoType>();
|
|
|
|
repeatForLambdaConversionFunctionCallingConvs(
|
|
S, *CallOpProto, [&](CallingConv CC) {
|
|
QualType InvokerFunctionTy =
|
|
S.getLambdaConversionFunctionResultType(CallOpProto, CC);
|
|
addFunctionPointerConversion(S, IntroducerRange, Class, CallOperator,
|
|
InvokerFunctionTy);
|
|
});
|
|
}
|
|
|
|
/// Add a lambda's conversion to block pointer.
|
|
static void addBlockPointerConversion(Sema &S,
|
|
SourceRange IntroducerRange,
|
|
CXXRecordDecl *Class,
|
|
CXXMethodDecl *CallOperator) {
|
|
const FunctionProtoType *CallOpProto =
|
|
CallOperator->getType()->castAs<FunctionProtoType>();
|
|
QualType FunctionTy = S.getLambdaConversionFunctionResultType(
|
|
CallOpProto, getLambdaConversionFunctionCallConv(S, CallOpProto));
|
|
QualType BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
|
|
|
|
FunctionProtoType::ExtProtoInfo ConversionEPI(
|
|
S.Context.getDefaultCallingConvention(
|
|
/*IsVariadic=*/false, /*IsCXXMethod=*/true));
|
|
ConversionEPI.TypeQuals = Qualifiers();
|
|
ConversionEPI.TypeQuals.addConst();
|
|
QualType ConvTy = S.Context.getFunctionType(BlockPtrTy, None, ConversionEPI);
|
|
|
|
SourceLocation Loc = IntroducerRange.getBegin();
|
|
DeclarationName Name
|
|
= S.Context.DeclarationNames.getCXXConversionFunctionName(
|
|
S.Context.getCanonicalType(BlockPtrTy));
|
|
DeclarationNameLoc NameLoc;
|
|
NameLoc.NamedType.TInfo = S.Context.getTrivialTypeSourceInfo(BlockPtrTy, Loc);
|
|
CXXConversionDecl *Conversion = CXXConversionDecl::Create(
|
|
S.Context, Class, Loc, DeclarationNameInfo(Name, Loc, NameLoc), ConvTy,
|
|
S.Context.getTrivialTypeSourceInfo(ConvTy, Loc),
|
|
/*isInline=*/true, ExplicitSpecifier(), ConstexprSpecKind::Unspecified,
|
|
CallOperator->getBody()->getEndLoc());
|
|
Conversion->setAccess(AS_public);
|
|
Conversion->setImplicit(true);
|
|
Class->addDecl(Conversion);
|
|
}
|
|
|
|
ExprResult Sema::BuildCaptureInit(const Capture &Cap,
|
|
SourceLocation ImplicitCaptureLoc,
|
|
bool IsOpenMPMapping) {
|
|
// VLA captures don't have a stored initialization expression.
|
|
if (Cap.isVLATypeCapture())
|
|
return ExprResult();
|
|
|
|
// An init-capture is initialized directly from its stored initializer.
|
|
if (Cap.isInitCapture())
|
|
return Cap.getVariable()->getInit();
|
|
|
|
// For anything else, build an initialization expression. For an implicit
|
|
// capture, the capture notionally happens at the capture-default, so use
|
|
// that location here.
|
|
SourceLocation Loc =
|
|
ImplicitCaptureLoc.isValid() ? ImplicitCaptureLoc : Cap.getLocation();
|
|
|
|
// C++11 [expr.prim.lambda]p21:
|
|
// When the lambda-expression is evaluated, the entities that
|
|
// are captured by copy are used to direct-initialize each
|
|
// corresponding non-static data member of the resulting closure
|
|
// object. (For array members, the array elements are
|
|
// direct-initialized in increasing subscript order.) These
|
|
// initializations are performed in the (unspecified) order in
|
|
// which the non-static data members are declared.
|
|
|
|
// C++ [expr.prim.lambda]p12:
|
|
// An entity captured by a lambda-expression is odr-used (3.2) in
|
|
// the scope containing the lambda-expression.
|
|
ExprResult Init;
|
|
IdentifierInfo *Name = nullptr;
|
|
if (Cap.isThisCapture()) {
|
|
QualType ThisTy = getCurrentThisType();
|
|
Expr *This = BuildCXXThisExpr(Loc, ThisTy, ImplicitCaptureLoc.isValid());
|
|
if (Cap.isCopyCapture())
|
|
Init = CreateBuiltinUnaryOp(Loc, UO_Deref, This);
|
|
else
|
|
Init = This;
|
|
} else {
|
|
assert(Cap.isVariableCapture() && "unknown kind of capture");
|
|
VarDecl *Var = Cap.getVariable();
|
|
Name = Var->getIdentifier();
|
|
Init = BuildDeclarationNameExpr(
|
|
CXXScopeSpec(), DeclarationNameInfo(Var->getDeclName(), Loc), Var);
|
|
}
|
|
|
|
// In OpenMP, the capture kind doesn't actually describe how to capture:
|
|
// variables are "mapped" onto the device in a process that does not formally
|
|
// make a copy, even for a "copy capture".
|
|
if (IsOpenMPMapping)
|
|
return Init;
|
|
|
|
if (Init.isInvalid())
|
|
return ExprError();
|
|
|
|
Expr *InitExpr = Init.get();
|
|
InitializedEntity Entity = InitializedEntity::InitializeLambdaCapture(
|
|
Name, Cap.getCaptureType(), Loc);
|
|
InitializationKind InitKind =
|
|
InitializationKind::CreateDirect(Loc, Loc, Loc);
|
|
InitializationSequence InitSeq(*this, Entity, InitKind, InitExpr);
|
|
return InitSeq.Perform(*this, Entity, InitKind, InitExpr);
|
|
}
|
|
|
|
ExprResult Sema::ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
|
|
Scope *CurScope) {
|
|
LambdaScopeInfo LSI = *cast<LambdaScopeInfo>(FunctionScopes.back());
|
|
ActOnFinishFunctionBody(LSI.CallOperator, Body);
|
|
return BuildLambdaExpr(StartLoc, Body->getEndLoc(), &LSI);
|
|
}
|
|
|
|
static LambdaCaptureDefault
|
|
mapImplicitCaptureStyle(CapturingScopeInfo::ImplicitCaptureStyle ICS) {
|
|
switch (ICS) {
|
|
case CapturingScopeInfo::ImpCap_None:
|
|
return LCD_None;
|
|
case CapturingScopeInfo::ImpCap_LambdaByval:
|
|
return LCD_ByCopy;
|
|
case CapturingScopeInfo::ImpCap_CapturedRegion:
|
|
case CapturingScopeInfo::ImpCap_LambdaByref:
|
|
return LCD_ByRef;
|
|
case CapturingScopeInfo::ImpCap_Block:
|
|
llvm_unreachable("block capture in lambda");
|
|
}
|
|
llvm_unreachable("Unknown implicit capture style");
|
|
}
|
|
|
|
bool Sema::CaptureHasSideEffects(const Capture &From) {
|
|
if (From.isInitCapture()) {
|
|
Expr *Init = From.getVariable()->getInit();
|
|
if (Init && Init->HasSideEffects(Context))
|
|
return true;
|
|
}
|
|
|
|
if (!From.isCopyCapture())
|
|
return false;
|
|
|
|
const QualType T = From.isThisCapture()
|
|
? getCurrentThisType()->getPointeeType()
|
|
: From.getCaptureType();
|
|
|
|
if (T.isVolatileQualified())
|
|
return true;
|
|
|
|
const Type *BaseT = T->getBaseElementTypeUnsafe();
|
|
if (const CXXRecordDecl *RD = BaseT->getAsCXXRecordDecl())
|
|
return !RD->isCompleteDefinition() || !RD->hasTrivialCopyConstructor() ||
|
|
!RD->hasTrivialDestructor();
|
|
|
|
return false;
|
|
}
|
|
|
|
bool Sema::DiagnoseUnusedLambdaCapture(SourceRange CaptureRange,
|
|
const Capture &From) {
|
|
if (CaptureHasSideEffects(From))
|
|
return false;
|
|
|
|
if (From.isVLATypeCapture())
|
|
return false;
|
|
|
|
auto diag = Diag(From.getLocation(), diag::warn_unused_lambda_capture);
|
|
if (From.isThisCapture())
|
|
diag << "'this'";
|
|
else
|
|
diag << From.getVariable();
|
|
diag << From.isNonODRUsed();
|
|
diag << FixItHint::CreateRemoval(CaptureRange);
|
|
return true;
|
|
}
|
|
|
|
/// Create a field within the lambda class or captured statement record for the
|
|
/// given capture.
|
|
FieldDecl *Sema::BuildCaptureField(RecordDecl *RD,
|
|
const sema::Capture &Capture) {
|
|
SourceLocation Loc = Capture.getLocation();
|
|
QualType FieldType = Capture.getCaptureType();
|
|
|
|
TypeSourceInfo *TSI = nullptr;
|
|
if (Capture.isVariableCapture()) {
|
|
auto *Var = Capture.getVariable();
|
|
if (Var->isInitCapture())
|
|
TSI = Capture.getVariable()->getTypeSourceInfo();
|
|
}
|
|
|
|
// FIXME: Should we really be doing this? A null TypeSourceInfo seems more
|
|
// appropriate, at least for an implicit capture.
|
|
if (!TSI)
|
|
TSI = Context.getTrivialTypeSourceInfo(FieldType, Loc);
|
|
|
|
// Build the non-static data member.
|
|
FieldDecl *Field =
|
|
FieldDecl::Create(Context, RD, /*StartLoc=*/Loc, /*IdLoc=*/Loc,
|
|
/*Id=*/nullptr, FieldType, TSI, /*BW=*/nullptr,
|
|
/*Mutable=*/false, ICIS_NoInit);
|
|
// If the variable being captured has an invalid type, mark the class as
|
|
// invalid as well.
|
|
if (!FieldType->isDependentType()) {
|
|
if (RequireCompleteSizedType(Loc, FieldType,
|
|
diag::err_field_incomplete_or_sizeless)) {
|
|
RD->setInvalidDecl();
|
|
Field->setInvalidDecl();
|
|
} else {
|
|
NamedDecl *Def;
|
|
FieldType->isIncompleteType(&Def);
|
|
if (Def && Def->isInvalidDecl()) {
|
|
RD->setInvalidDecl();
|
|
Field->setInvalidDecl();
|
|
}
|
|
}
|
|
}
|
|
Field->setImplicit(true);
|
|
Field->setAccess(AS_private);
|
|
RD->addDecl(Field);
|
|
|
|
if (Capture.isVLATypeCapture())
|
|
Field->setCapturedVLAType(Capture.getCapturedVLAType());
|
|
|
|
return Field;
|
|
}
|
|
|
|
ExprResult Sema::BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
|
|
LambdaScopeInfo *LSI) {
|
|
// Collect information from the lambda scope.
|
|
SmallVector<LambdaCapture, 4> Captures;
|
|
SmallVector<Expr *, 4> CaptureInits;
|
|
SourceLocation CaptureDefaultLoc = LSI->CaptureDefaultLoc;
|
|
LambdaCaptureDefault CaptureDefault =
|
|
mapImplicitCaptureStyle(LSI->ImpCaptureStyle);
|
|
CXXRecordDecl *Class;
|
|
CXXMethodDecl *CallOperator;
|
|
SourceRange IntroducerRange;
|
|
bool ExplicitParams;
|
|
bool ExplicitResultType;
|
|
CleanupInfo LambdaCleanup;
|
|
bool ContainsUnexpandedParameterPack;
|
|
bool IsGenericLambda;
|
|
{
|
|
CallOperator = LSI->CallOperator;
|
|
Class = LSI->Lambda;
|
|
IntroducerRange = LSI->IntroducerRange;
|
|
ExplicitParams = LSI->ExplicitParams;
|
|
ExplicitResultType = !LSI->HasImplicitReturnType;
|
|
LambdaCleanup = LSI->Cleanup;
|
|
ContainsUnexpandedParameterPack = LSI->ContainsUnexpandedParameterPack;
|
|
IsGenericLambda = Class->isGenericLambda();
|
|
|
|
CallOperator->setLexicalDeclContext(Class);
|
|
Decl *TemplateOrNonTemplateCallOperatorDecl =
|
|
CallOperator->getDescribedFunctionTemplate()
|
|
? CallOperator->getDescribedFunctionTemplate()
|
|
: cast<Decl>(CallOperator);
|
|
|
|
// FIXME: Is this really the best choice? Keeping the lexical decl context
|
|
// set as CurContext seems more faithful to the source.
|
|
TemplateOrNonTemplateCallOperatorDecl->setLexicalDeclContext(Class);
|
|
|
|
PopExpressionEvaluationContext();
|
|
|
|
// True if the current capture has a used capture or default before it.
|
|
bool CurHasPreviousCapture = CaptureDefault != LCD_None;
|
|
SourceLocation PrevCaptureLoc = CurHasPreviousCapture ?
|
|
CaptureDefaultLoc : IntroducerRange.getBegin();
|
|
|
|
for (unsigned I = 0, N = LSI->Captures.size(); I != N; ++I) {
|
|
const Capture &From = LSI->Captures[I];
|
|
|
|
if (From.isInvalid())
|
|
return ExprError();
|
|
|
|
assert(!From.isBlockCapture() && "Cannot capture __block variables");
|
|
bool IsImplicit = I >= LSI->NumExplicitCaptures;
|
|
SourceLocation ImplicitCaptureLoc =
|
|
IsImplicit ? CaptureDefaultLoc : SourceLocation();
|
|
|
|
// Use source ranges of explicit captures for fixits where available.
|
|
SourceRange CaptureRange = LSI->ExplicitCaptureRanges[I];
|
|
|
|
// Warn about unused explicit captures.
|
|
bool IsCaptureUsed = true;
|
|
if (!CurContext->isDependentContext() && !IsImplicit &&
|
|
!From.isODRUsed()) {
|
|
// Initialized captures that are non-ODR used may not be eliminated.
|
|
// FIXME: Where did the IsGenericLambda here come from?
|
|
bool NonODRUsedInitCapture =
|
|
IsGenericLambda && From.isNonODRUsed() && From.isInitCapture();
|
|
if (!NonODRUsedInitCapture) {
|
|
bool IsLast = (I + 1) == LSI->NumExplicitCaptures;
|
|
SourceRange FixItRange;
|
|
if (CaptureRange.isValid()) {
|
|
if (!CurHasPreviousCapture && !IsLast) {
|
|
// If there are no captures preceding this capture, remove the
|
|
// following comma.
|
|
FixItRange = SourceRange(CaptureRange.getBegin(),
|
|
getLocForEndOfToken(CaptureRange.getEnd()));
|
|
} else {
|
|
// Otherwise, remove the comma since the last used capture.
|
|
FixItRange = SourceRange(getLocForEndOfToken(PrevCaptureLoc),
|
|
CaptureRange.getEnd());
|
|
}
|
|
}
|
|
|
|
IsCaptureUsed = !DiagnoseUnusedLambdaCapture(FixItRange, From);
|
|
}
|
|
}
|
|
|
|
if (CaptureRange.isValid()) {
|
|
CurHasPreviousCapture |= IsCaptureUsed;
|
|
PrevCaptureLoc = CaptureRange.getEnd();
|
|
}
|
|
|
|
// Map the capture to our AST representation.
|
|
LambdaCapture Capture = [&] {
|
|
if (From.isThisCapture()) {
|
|
// Capturing 'this' implicitly with a default of '[=]' is deprecated,
|
|
// because it results in a reference capture. Don't warn prior to
|
|
// C++2a; there's nothing that can be done about it before then.
|
|
if (getLangOpts().CPlusPlus20 && IsImplicit &&
|
|
CaptureDefault == LCD_ByCopy) {
|
|
Diag(From.getLocation(), diag::warn_deprecated_this_capture);
|
|
Diag(CaptureDefaultLoc, diag::note_deprecated_this_capture)
|
|
<< FixItHint::CreateInsertion(
|
|
getLocForEndOfToken(CaptureDefaultLoc), ", this");
|
|
}
|
|
return LambdaCapture(From.getLocation(), IsImplicit,
|
|
From.isCopyCapture() ? LCK_StarThis : LCK_This);
|
|
} else if (From.isVLATypeCapture()) {
|
|
return LambdaCapture(From.getLocation(), IsImplicit, LCK_VLAType);
|
|
} else {
|
|
assert(From.isVariableCapture() && "unknown kind of capture");
|
|
VarDecl *Var = From.getVariable();
|
|
LambdaCaptureKind Kind =
|
|
From.isCopyCapture() ? LCK_ByCopy : LCK_ByRef;
|
|
return LambdaCapture(From.getLocation(), IsImplicit, Kind, Var,
|
|
From.getEllipsisLoc());
|
|
}
|
|
}();
|
|
|
|
// Form the initializer for the capture field.
|
|
ExprResult Init = BuildCaptureInit(From, ImplicitCaptureLoc);
|
|
|
|
// FIXME: Skip this capture if the capture is not used, the initializer
|
|
// has no side-effects, the type of the capture is trivial, and the
|
|
// lambda is not externally visible.
|
|
|
|
// Add a FieldDecl for the capture and form its initializer.
|
|
BuildCaptureField(Class, From);
|
|
Captures.push_back(Capture);
|
|
CaptureInits.push_back(Init.get());
|
|
|
|
if (LangOpts.CUDA)
|
|
CUDACheckLambdaCapture(CallOperator, From);
|
|
}
|
|
|
|
Class->setCaptures(Context, Captures);
|
|
|
|
// C++11 [expr.prim.lambda]p6:
|
|
// The closure type for a lambda-expression with no lambda-capture
|
|
// has a public non-virtual non-explicit const conversion function
|
|
// to pointer to function having the same parameter and return
|
|
// types as the closure type's function call operator.
|
|
if (Captures.empty() && CaptureDefault == LCD_None)
|
|
addFunctionPointerConversions(*this, IntroducerRange, Class,
|
|
CallOperator);
|
|
|
|
// Objective-C++:
|
|
// The closure type for a lambda-expression has a public non-virtual
|
|
// non-explicit const conversion function to a block pointer having the
|
|
// same parameter and return types as the closure type's function call
|
|
// operator.
|
|
// FIXME: Fix generic lambda to block conversions.
|
|
if (getLangOpts().Blocks && getLangOpts().ObjC && !IsGenericLambda)
|
|
addBlockPointerConversion(*this, IntroducerRange, Class, CallOperator);
|
|
|
|
// Finalize the lambda class.
|
|
SmallVector<Decl*, 4> Fields(Class->fields());
|
|
ActOnFields(nullptr, Class->getLocation(), Class, Fields, SourceLocation(),
|
|
SourceLocation(), ParsedAttributesView());
|
|
CheckCompletedCXXClass(nullptr, Class);
|
|
}
|
|
|
|
Cleanup.mergeFrom(LambdaCleanup);
|
|
|
|
LambdaExpr *Lambda = LambdaExpr::Create(Context, Class, IntroducerRange,
|
|
CaptureDefault, CaptureDefaultLoc,
|
|
ExplicitParams, ExplicitResultType,
|
|
CaptureInits, EndLoc,
|
|
ContainsUnexpandedParameterPack);
|
|
// If the lambda expression's call operator is not explicitly marked constexpr
|
|
// and we are not in a dependent context, analyze the call operator to infer
|
|
// its constexpr-ness, suppressing diagnostics while doing so.
|
|
if (getLangOpts().CPlusPlus17 && !CallOperator->isInvalidDecl() &&
|
|
!CallOperator->isConstexpr() &&
|
|
!isa<CoroutineBodyStmt>(CallOperator->getBody()) &&
|
|
!Class->getDeclContext()->isDependentContext()) {
|
|
CallOperator->setConstexprKind(
|
|
CheckConstexprFunctionDefinition(CallOperator,
|
|
CheckConstexprKind::CheckValid)
|
|
? ConstexprSpecKind::Constexpr
|
|
: ConstexprSpecKind::Unspecified);
|
|
}
|
|
|
|
// Emit delayed shadowing warnings now that the full capture list is known.
|
|
DiagnoseShadowingLambdaDecls(LSI);
|
|
|
|
if (!CurContext->isDependentContext()) {
|
|
switch (ExprEvalContexts.back().Context) {
|
|
// C++11 [expr.prim.lambda]p2:
|
|
// A lambda-expression shall not appear in an unevaluated operand
|
|
// (Clause 5).
|
|
case ExpressionEvaluationContext::Unevaluated:
|
|
case ExpressionEvaluationContext::UnevaluatedList:
|
|
case ExpressionEvaluationContext::UnevaluatedAbstract:
|
|
// C++1y [expr.const]p2:
|
|
// A conditional-expression e is a core constant expression unless the
|
|
// evaluation of e, following the rules of the abstract machine, would
|
|
// evaluate [...] a lambda-expression.
|
|
//
|
|
// This is technically incorrect, there are some constant evaluated contexts
|
|
// where this should be allowed. We should probably fix this when DR1607 is
|
|
// ratified, it lays out the exact set of conditions where we shouldn't
|
|
// allow a lambda-expression.
|
|
case ExpressionEvaluationContext::ConstantEvaluated:
|
|
// We don't actually diagnose this case immediately, because we
|
|
// could be within a context where we might find out later that
|
|
// the expression is potentially evaluated (e.g., for typeid).
|
|
ExprEvalContexts.back().Lambdas.push_back(Lambda);
|
|
break;
|
|
|
|
case ExpressionEvaluationContext::DiscardedStatement:
|
|
case ExpressionEvaluationContext::PotentiallyEvaluated:
|
|
case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
|
|
break;
|
|
}
|
|
}
|
|
|
|
return MaybeBindToTemporary(Lambda);
|
|
}
|
|
|
|
ExprResult Sema::BuildBlockForLambdaConversion(SourceLocation CurrentLocation,
|
|
SourceLocation ConvLocation,
|
|
CXXConversionDecl *Conv,
|
|
Expr *Src) {
|
|
// Make sure that the lambda call operator is marked used.
|
|
CXXRecordDecl *Lambda = Conv->getParent();
|
|
CXXMethodDecl *CallOperator
|
|
= cast<CXXMethodDecl>(
|
|
Lambda->lookup(
|
|
Context.DeclarationNames.getCXXOperatorName(OO_Call)).front());
|
|
CallOperator->setReferenced();
|
|
CallOperator->markUsed(Context);
|
|
|
|
ExprResult Init = PerformCopyInitialization(
|
|
InitializedEntity::InitializeLambdaToBlock(ConvLocation, Src->getType(),
|
|
/*NRVO=*/false),
|
|
CurrentLocation, Src);
|
|
if (!Init.isInvalid())
|
|
Init = ActOnFinishFullExpr(Init.get(), /*DiscardedValue*/ false);
|
|
|
|
if (Init.isInvalid())
|
|
return ExprError();
|
|
|
|
// Create the new block to be returned.
|
|
BlockDecl *Block = BlockDecl::Create(Context, CurContext, ConvLocation);
|
|
|
|
// Set the type information.
|
|
Block->setSignatureAsWritten(CallOperator->getTypeSourceInfo());
|
|
Block->setIsVariadic(CallOperator->isVariadic());
|
|
Block->setBlockMissingReturnType(false);
|
|
|
|
// Add parameters.
|
|
SmallVector<ParmVarDecl *, 4> BlockParams;
|
|
for (unsigned I = 0, N = CallOperator->getNumParams(); I != N; ++I) {
|
|
ParmVarDecl *From = CallOperator->getParamDecl(I);
|
|
BlockParams.push_back(ParmVarDecl::Create(
|
|
Context, Block, From->getBeginLoc(), From->getLocation(),
|
|
From->getIdentifier(), From->getType(), From->getTypeSourceInfo(),
|
|
From->getStorageClass(),
|
|
/*DefArg=*/nullptr));
|
|
}
|
|
Block->setParams(BlockParams);
|
|
|
|
Block->setIsConversionFromLambda(true);
|
|
|
|
// Add capture. The capture uses a fake variable, which doesn't correspond
|
|
// to any actual memory location. However, the initializer copy-initializes
|
|
// the lambda object.
|
|
TypeSourceInfo *CapVarTSI =
|
|
Context.getTrivialTypeSourceInfo(Src->getType());
|
|
VarDecl *CapVar = VarDecl::Create(Context, Block, ConvLocation,
|
|
ConvLocation, nullptr,
|
|
Src->getType(), CapVarTSI,
|
|
SC_None);
|
|
BlockDecl::Capture Capture(/*variable=*/CapVar, /*byRef=*/false,
|
|
/*nested=*/false, /*copy=*/Init.get());
|
|
Block->setCaptures(Context, Capture, /*CapturesCXXThis=*/false);
|
|
|
|
// Add a fake function body to the block. IR generation is responsible
|
|
// for filling in the actual body, which cannot be expressed as an AST.
|
|
Block->setBody(new (Context) CompoundStmt(ConvLocation));
|
|
|
|
// Create the block literal expression.
|
|
Expr *BuildBlock = new (Context) BlockExpr(Block, Conv->getConversionType());
|
|
ExprCleanupObjects.push_back(Block);
|
|
Cleanup.setExprNeedsCleanups(true);
|
|
|
|
return BuildBlock;
|
|
}
|