Fun with parameter attributes: For several of the "synthetic" parameters added to D functions, we can apply noalias and nocapture. They are sret parameters, 'nest' pointers passed to nested functions, and _argptr: Nocapture: - Sret and nest are nocapture because they don't represent D-level variables, and thus the callee can't (validly) obtain a pointer to them, let alone keep it around after it returns. - _argptr is nocapture because although the callee has access to it as a pointer, that pointer is invalidated when it returns. All three are noalias because they're function-local variables - Sret and _argptr are noalias because they're freshly alloca'd memory only used for a single function call that's not allowed to keep an aliasing pointer to it around (since the parameter is nocapture). - 'Nest' is noalias because the callee only ever has access to one such pointer per parent function, and every parent function has a different one. This commit also ensures attributes set on sret, _arguments and _argptr are propagated to calls to such functions. It also adds one exception to the general rule that attributes on function types should propagate to calls: the type of a delegate's function pointer has a 'nest' parameter, but this can either be a true 'nest' (for delegates to nested functions) or a 'this' (for delegates to member functions). Since 'this' is neither noalias nor nocapture, and there's generally no way to tell which one it is, we remove these attributes at the call site if the callee is a delegate.

#ifndef GEN_LLVM_H
#define GEN_LLVM_H

#include "llvm/Type.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Constants.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/CallingConv.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Function.h"
#include "llvm/Module.h"
#include "llvm/Value.h"
#include "llvm/Attributes.h"

#include "llvm/Target/TargetData.h"

#include "llvm/Analysis/DebugInfo.h"

#include "llvm/Support/CallSite.h"

#include "llvm/Support/IRBuilder.h"
using llvm::IRBuilder;

// for WriteTypeSymbolic
#include "llvm/Assembly/Writer.h"

#define GET_INTRINSIC_DECL(_X) (llvm::Intrinsic::getDeclaration(gIR->module, llvm::Intrinsic:: _X ))

// shortcuts for the common llvm types

#define LLType llvm::Type
#define LLFunctionType llvm::FunctionType
#define LLPointerType llvm::PointerType
#define LLStructType llvm::StructType
#define LLArrayType llvm::ArrayType
#define LLIntegerType llvm::IntegerType
#define LLOpaqueType llvm::OpaqueType

#define LLValue llvm::Value
#define LLGlobalValue llvm::GlobalValue
#define LLGlobalVariable llvm::GlobalVariable
#define LLFunction llvm::Function

#define LLConstant llvm::Constant
#define LLConstantStruct llvm::ConstantStruct
#define LLConstantArray llvm::ConstantArray
#define LLConstantInt llvm::ConstantInt
#define LLConstantFP llvm::ConstantFP

#define LLPATypeHolder llvm::PATypeHolder

#define LLCallSite llvm::CallSite

#define LLSmallVector llvm::SmallVector

using llvm::APFloat;
using llvm::APInt;

#endif // GEN_LLVM_H