Promote atomic type sizes up to a power of two, capped by

MaxAtomicPromoteWidth.  Fix a ton of terrible bugs with
_Atomic types and (non-intrinsic-mediated) loads and stores
thereto.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176658 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 23 insertions, 1 deletions

diff --git a/lib/CodeGen/CodeGenTypes.cpp b/lib/CodeGen/CodeGenTypes.cpp
index 259d10673d..8fc78e3de6 100644
--- a/lib/CodeGen/CodeGenTypes.cpp
+++ b/lib/CodeGen/CodeGenTypes.cpp
@@ -582,7 +582,21 @@ llvm::Type *CodeGenTypes::ConvertType(QualType T) {
   }
 
   case Type::Atomic: {
-    ResultType = ConvertType(cast<AtomicType>(Ty)->getValueType());
+    QualType valueType = cast<AtomicType>(Ty)->getValueType();
+    ResultType = ConvertTypeForMem(valueType);
+
+    // Pad out to the inflated size if necessary.
+    uint64_t valueSize = Context.getTypeSize(valueType);
+    uint64_t atomicSize = Context.getTypeSize(Ty);
+    if (valueSize != atomicSize) {
+      assert(valueSize < atomicSize);
+      llvm::Type *elts[] = {
+        ResultType,
+        llvm::ArrayType::get(CGM.Int8Ty, (atomicSize - valueSize) / 8)
+      };
+      ResultType = llvm::StructType::get(getLLVMContext(),
+                                         llvm::makeArrayRef(elts));
+    }
     break;
   }
   }
@@ -593,6 +607,14 @@ llvm::Type *CodeGenTypes::ConvertType(QualType T) {
   return ResultType;
 }
 
+bool CodeGenModule::isPaddedAtomicType(QualType type) {
+  return isPaddedAtomicType(type->castAs<AtomicType>());
+}
+
+bool CodeGenModule::isPaddedAtomicType(const AtomicType *type) {
+  return Context.getTypeSize(type) != Context.getTypeSize(type->getValueType());
+}
+
 /// ConvertRecordDeclType - Lay out a tagged decl type like struct or union.
 llvm::StructType *CodeGenTypes::ConvertRecordDeclType(const RecordDecl *RD) {
   // TagDecl's are not necessarily unique, instead use the (clang)