Some improvements to the handling of C11 atomic types:
- Add atomic-to/from-nonatomic cast types
- Emit atomic operations for arithmetic on atomic types
- Emit non-atomic stores for initialisation of atomic types, but atomic stores and loads for every other store / load
- Add a __atomic_init() intrinsic which does a non-atomic store to an _Atomic() type. This is needed for the corresponding C11 stdatomic.h function.
- Enables the relevant __has_feature() checks. The feature isn't 100% complete yet, but it's done enough that we want people testing it.
Still to do:
- Make the arithmetic operations on atomic types (e.g. Atomic(int) foo = 1; foo++;) use the correct LLVM intrinsic if one exists, not a loop with a cmpxchg.
- Add a signal fence builtin
- Properly set the fenv state in atomic operations on floating point values
- Correctly handle things like _Atomic(_Complex double) which are too large for an atomic cmpxchg on some platforms (this requires working out what 'correctly' means in this context)
- Fix the many remaining corner cases
llvm-svn: 148242
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index dd7cdb6..7c7501b 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -494,7 +494,7 @@
llvm::Value *value = EmitScalarExpr(init);
if (capturedByInit)
drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
- EmitStoreThroughLValue(RValue::get(value), lvalue);
+ EmitStoreThroughLValue(RValue::get(value), lvalue, true);
return;
}
@@ -535,7 +535,7 @@
// Otherwise just do a simple store.
else
- EmitStoreOfScalar(zero, tempLV);
+ EmitStoreOfScalar(zero, tempLV, /* isInitialization */ true);
}
// Emit the initializer.
@@ -581,19 +581,19 @@
// both __weak and __strong, but __weak got filtered out above.
if (accessedByInit && lifetime == Qualifiers::OCL_Strong) {
llvm::Value *oldValue = EmitLoadOfScalar(lvalue);
- EmitStoreOfScalar(value, lvalue);
+ EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
EmitARCRelease(oldValue, /*precise*/ false);
return;
}
- EmitStoreOfScalar(value, lvalue);
+ EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
}
/// EmitScalarInit - Initialize the given lvalue with the given object.
void CodeGenFunction::EmitScalarInit(llvm::Value *init, LValue lvalue) {
Qualifiers::ObjCLifetime lifetime = lvalue.getObjCLifetime();
if (!lifetime)
- return EmitStoreThroughLValue(RValue::get(init), lvalue);
+ return EmitStoreThroughLValue(RValue::get(init), lvalue, true);
switch (lifetime) {
case Qualifiers::OCL_None:
@@ -617,7 +617,7 @@
break;
}
- EmitStoreOfScalar(init, lvalue);
+ EmitStoreOfScalar(init, lvalue, /* isInitialization */ true);
}
/// canEmitInitWithFewStoresAfterMemset - Decide whether we can emit the
@@ -1045,7 +1045,7 @@
RValue rvalue = EmitReferenceBindingToExpr(init, D);
if (capturedByInit)
drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
- EmitStoreThroughLValue(rvalue, lvalue);
+ EmitStoreThroughLValue(rvalue, lvalue, true);
} else if (!hasAggregateLLVMType(type)) {
EmitScalarInit(init, D, lvalue, capturedByInit);
} else if (type->isAnyComplexType()) {
@@ -1505,7 +1505,7 @@
if (doStore) {
LValue lv = MakeAddrLValue(DeclPtr, Ty,
getContext().getDeclAlign(&D));
- EmitStoreOfScalar(Arg, lv);
+ EmitStoreOfScalar(Arg, lv, /* isInitialization */ true);
}
}