diff options
author | John McCall <rjmccall@apple.com> | 2013-04-08 23:27:49 +0000 |
---|---|---|
committer | John McCall <rjmccall@apple.com> | 2013-04-08 23:27:49 +0000 |
commit | 4b9bcd667776932e9b4c84144a9e7e8d581ffa63 (patch) | |
tree | efb3ae39d700257c35085fd9c58ae905ebe25a4b /lib/CodeGen/CGBlocks.cpp | |
parent | 484f6fa0bd6b16b64e5c4cb40260f69a3dd52b4a (diff) |
Don't copy just to capture a strong block pointer under ARC.
It turns out that the optimizer can't eliminate this without extra
information, for which there's a separate bug.
rdar://13588325
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179069 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/CGBlocks.cpp')
-rw-r--r-- | lib/CodeGen/CGBlocks.cpp | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp index 317d3c217d..ab9793132c 100644 --- a/lib/CodeGen/CGBlocks.cpp +++ b/lib/CodeGen/CGBlocks.cpp @@ -753,6 +753,7 @@ llvm::Value *CodeGenFunction::EmitBlockLiteral(const CGBlockInfo &blockInfo) { if (capture.isConstant()) continue; QualType type = variable->getType(); + CharUnits align = getContext().getDeclAlign(variable); // This will be a [[type]]*, except that a byref entry will just be // an i8**. @@ -796,21 +797,21 @@ llvm::Value *CodeGenFunction::EmitBlockLiteral(const CGBlockInfo &blockInfo) { if (ci->isByRef()) { // Get a void* that points to the byref struct. if (ci->isNested()) - src = Builder.CreateLoad(src, "byref.capture"); + src = Builder.CreateAlignedLoad(src, align.getQuantity(), + "byref.capture"); else src = Builder.CreateBitCast(src, VoidPtrTy); // Write that void* into the capture field. - Builder.CreateStore(src, blockField); + Builder.CreateAlignedStore(src, blockField, align.getQuantity()); // If we have a copy constructor, evaluate that into the block field. } else if (const Expr *copyExpr = ci->getCopyExpr()) { if (blockDecl->isConversionFromLambda()) { // If we have a lambda conversion, emit the expression // directly into the block instead. - CharUnits Align = getContext().getTypeAlignInChars(type); AggValueSlot Slot = - AggValueSlot::forAddr(blockField, Align, Qualifiers(), + AggValueSlot::forAddr(blockField, align, Qualifiers(), AggValueSlot::IsDestructed, AggValueSlot::DoesNotNeedGCBarriers, AggValueSlot::IsNotAliased); @@ -821,7 +822,27 @@ llvm::Value *CodeGenFunction::EmitBlockLiteral(const CGBlockInfo &blockInfo) { // If it's a reference variable, copy the reference into the block field. } else if (type->isReferenceType()) { - Builder.CreateStore(Builder.CreateLoad(src, "ref.val"), blockField); + llvm::Value *ref = + Builder.CreateAlignedLoad(src, align.getQuantity(), "ref.val"); + Builder.CreateAlignedStore(ref, blockField, align.getQuantity()); + + // If this is an ARC __strong block-pointer variable, don't do a + // block copy. + // + // TODO: this can be generalized into the normal initialization logic: + // we should never need to do a block-copy when initializing a local + // variable, because the local variable's lifetime should be strictly + // contained within the stack block's. + } else if (type.getObjCLifetime() == Qualifiers::OCL_Strong && + type->isBlockPointerType()) { + // Load the block and do a simple retain. + LValue srcLV = MakeAddrLValue(src, type, align); + llvm::Value *value = EmitLoadOfScalar(srcLV); + value = EmitARCRetainNonBlock(value); + + // Do a primitive store to the block field. + LValue destLV = MakeAddrLValue(blockField, type, align); + EmitStoreOfScalar(value, destLV, /*init*/ true); // Otherwise, fake up a POD copy into the block field. } else { @@ -839,8 +860,7 @@ llvm::Value *CodeGenFunction::EmitBlockLiteral(const CGBlockInfo &blockInfo) { ImplicitCastExpr l2r(ImplicitCastExpr::OnStack, type, CK_LValueToRValue, &declRef, VK_RValue); EmitExprAsInit(&l2r, &blockFieldPseudoVar, - MakeAddrLValue(blockField, type, - getContext().getDeclAlign(variable)), + MakeAddrLValue(blockField, type, align), /*captured by init*/ false); } |