Distinguish `__block` variables that are captured by escaping blocks
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
This reapplies r343518 after fixing a use-after-free bug in function
Sema::ActOnBlockStmtExpr where the BlockScopeInfo was dereferenced after
it was popped and deleted.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 343542
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index b74937e..028aa96 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -2486,7 +2486,7 @@
}
assert(isa<BlockDecl>(CurCodeDecl));
- Address addr = GetAddrOfBlockDecl(VD, VD->hasAttr<BlocksAttr>());
+ Address addr = GetAddrOfBlockDecl(VD);
return MakeAddrLValue(addr, T, AlignmentSource::Decl);
}
}
@@ -2538,7 +2538,7 @@
}
// Drill into block byref variables.
- bool isBlockByref = VD->hasAttr<BlocksAttr>();
+ bool isBlockByref = VD->isEscapingByref();
if (isBlockByref) {
addr = emitBlockByrefAddress(addr, VD);
}