On Tue, 2007-01-02 at 22:58 -0800, Reid Spencer wrote:
> To make it even easier, here's a replacement for gcc/llvm-types.cpp
Scratch that. Sent the wrong file. Try this one. Sorry.
Reid.
>
> Reid.
>
> On Tue, 2007-01-02 at 22:54 -0800, Reid Spencer wrote:
> > The attached patch is already contained in the previous cumulative PR950
> > patch. This contains just today's changes so it can be more easily
> > applied to the Apple internal SVN server.
> >
> > Reid.
> > _______________________________________________
> > llvm-commits mailing list
> > llvm-commits@cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
> _______________________________________________
> llvm-commits mailing list
> llvm-commits@cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
/* APPLE LOCAL begin LLVM (ENTIRE FILE!) */
/* Tree type to LLVM type converter
Copyright (C) 2005 Free Software Foundation, Inc.
Contributed by Chris Lattner ([EMAIL PROTECTED])
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
//===----------------------------------------------------------------------===//
// This is the code that converts GCC tree types into LLVM types.
//===----------------------------------------------------------------------===//
#include "llvm-internal.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/ADT/StringExtras.h"
#include <iostream>
#include <map>
extern "C" {
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tree.h"
}
#include "llvm-abi.h"
//===----------------------------------------------------------------------===//
// Recursive Type Handling Code and Data
//===----------------------------------------------------------------------===//
// Recursive types are a major pain to handle for a couple of reasons. Because
// of this, when we start parsing a struct or a union, we globally change how
// POINTER_TYPE and REFERENCE_TYPE are handled. In particular, instead of
// actually recursing and computing the type they point to, they will return an
// opaque*, and remember that they did this in PointersToReresolve.
//===----------------------------------------------------------------------===//
// Type Conversion Utilities
//===----------------------------------------------------------------------===//
static inline const Type *getIntegerType(unsigned Bits, bool isUnsigned) {
switch (Bits*2+isUnsigned) {
default: assert(0 && "Unknown integral type size!");
case 8*2+0: return Type::Int8Ty;
case 8*2+1: return Type::Int8Ty;
case 16*2+0: return Type::Int16Ty;
case 16*2+1: return Type::Int16Ty;
case 32*2+0: return Type::Int32Ty;
case 32*2+1: return Type::Int32Ty;
case 64*2+0: return Type::Int64Ty;
case 64*2+1: return Type::Int64Ty;
case 128*2+0:
case 128*2+1:
static bool Warned = false;
if (!Warned) fprintf(stderr, "WARNING: 128-bit integers not supported!\n");
Warned = true;
return isUnsigned ? Type::Int64Ty : Type::Int64Ty;
}
}
// isPassedByInvisibleReference - Return true if an argument of the specified
// type should be passed in by invisible reference.
//
bool isPassedByInvisibleReference(tree Type) {
// FIXME: Search for TREE_ADDRESSABLE in calls.c, and see if there are other
// cases that make arguments automatically passed in by reference.
return TREE_ADDRESSABLE(Type);
}
/// GetTypeName - Return a fully qualified (with namespace prefixes) name for
/// the specified type.
static std::string GetTypeName(const char *Prefix, tree type) {
const char *Name = "anon";
if (TYPE_NAME(type))
if (TREE_CODE(TYPE_NAME(type)) == IDENTIFIER_NODE)
Name = IDENTIFIER_POINTER(TYPE_NAME(type));
else
Name = IDENTIFIER_POINTER(DECL_NAME(TYPE_NAME(type)));
std::string ContextStr;
tree Context = TYPE_CONTEXT(type);
while (Context) {
switch (TREE_CODE(Context)) {
case TRANSLATION_UNIT_DECL: Context = 0; break; // Done.
case RECORD_TYPE:
case NAMESPACE_DECL:
if (TREE_CODE(Context) == RECORD_TYPE) {
if (TYPE_NAME(Context)) {
std::string NameFrag;
if (TREE_CODE(TYPE_NAME(Context)) == IDENTIFIER_NODE) {
NameFrag = IDENTIFIER_POINTER(TYPE_NAME(Context));
} else {
NameFrag = IDENTIFIER_POINTER(DECL_NAME(TYPE_NAME(Context)));
}
ContextStr = NameFrag + "::" + ContextStr;
Context = TYPE_CONTEXT(Context);
break;
}
// Anonymous record, fall through.
} else if (DECL_NAME(Context)
/*&& DECL_NAME(Context) != anonymous_namespace_name*/){
assert(TREE_CODE(DECL_NAME(Context)) == IDENTIFIER_NODE);
std::string NamespaceName = IDENTIFIER_POINTER(DECL_NAME(Context));
ContextStr = NamespaceName + "::" + ContextStr;
Context = DECL_CONTEXT(Context);
break;
}
// FALL THROUGH for anonymous namespaces and records!
default: {
// If this is a structure type defined inside of a function or other block
// scope, make sure to make the type name unique by putting a unique ID
// in it.
static unsigned UniqueID = 0;
ContextStr = "." + utostr(UniqueID++);
Context = 0; // Stop looking at context
break;
}
}
}
return Prefix + ContextStr + Name;
}
//===----------------------------------------------------------------------===//
// Abstract Type Refinement Helpers
//===----------------------------------------------------------------------===//
//
// This code is built to make sure that the TYPE_LLVM field on tree types are
// updated when LLVM types are refined. This prevents dangling pointers from
// occuring due to type coallescing.
//
namespace {
class TypeRefinementDatabase : public AbstractTypeUser {
virtual void refineAbstractType(const DerivedType *OldTy,
const Type *NewTy);
virtual void typeBecameConcrete(const DerivedType *AbsTy);
// TypeUsers - For each abstract LLVM type, we keep track of all of the GCC
// types that point to it.
std::map<const Type*, std::vector<tree> > TypeUsers;
public:
/// setType - call SET_TYPE_LLVM(type, Ty), associating the type with the
/// specified tree type. In addition, if the LLVM type is an abstract type,
/// we add it to our data structure to track it.
inline const Type *setType(tree type, const Type *Ty) {
if (GET_TYPE_LLVM(type))
RemoveTypeFromTable(type);
if (Ty->isAbstract()) {
std::vector<tree> &Users = TypeUsers[Ty];
if (Users.empty()) Ty->addAbstractTypeUser(this);
Users.push_back(type);
}
return SET_TYPE_LLVM(type, Ty);
}
void RemoveTypeFromTable(tree type);
void dump() const;
};
/// TypeDB - The main global type database.
TypeRefinementDatabase TypeDB;
}
/// RemoveTypeFromTable - We're about to change the LLVM type of 'type'
///
void TypeRefinementDatabase::RemoveTypeFromTable(tree type) {
const Type *Ty = GET_TYPE_LLVM(type);
if (!Ty->isAbstract()) return;
std::map<const Type*, std::vector<tree> >::iterator I = TypeUsers.find(Ty);
assert(I != TypeUsers.end() && "Using an abstract type but not in table?");
bool FoundIt = false;
for (unsigned i = 0, e = I->second.size(); i != e; ++i)
if (I->second[i] == type) {
FoundIt = true;
std::swap(I->second[i], I->second.back());
I->second.pop_back();
break;
}
assert(FoundIt && "Using an abstract type but not in table?");
// If the type plane is now empty, nuke it.
if (I->second.empty()) {
TypeUsers.erase(I);
Ty->removeAbstractTypeUser(this);
}
}
/// refineAbstractType - The callback method invoked when an abstract type is
/// resolved to another type. An object must override this method to update
/// its internal state to reference NewType instead of OldType.
///
void TypeRefinementDatabase::refineAbstractType(const DerivedType *OldTy,
const Type *NewTy) {
if (OldTy == NewTy && OldTy->isAbstract()) return; // Nothing to do.
std::map<const Type*, std::vector<tree> >::iterator I = TypeUsers.find(OldTy);
assert(I != TypeUsers.end() && "Using an abstract type but not in table?");
if (!NewTy->isAbstract()) {
// If the type became concrete, update everything pointing to it, and remove
// all of our entries from the map.
if (OldTy != NewTy)
for (unsigned i = 0, e = I->second.size(); i != e; ++i)
SET_TYPE_LLVM(I->second[i], NewTy);
} else {
// Otherwise, it was refined to another instance of an abstract type. Move
// everything over and stop monitoring OldTy.
std::vector<tree> &NewSlot = TypeUsers[NewTy];
if (NewSlot.empty()) NewTy->addAbstractTypeUser(this);
for (unsigned i = 0, e = I->second.size(); i != e; ++i) {
NewSlot.push_back(I->second[i]);
SET_TYPE_LLVM(I->second[i], NewTy);
}
}
TypeUsers.erase(I);
// Next, remove OldTy's entry in the TargetData object if it has one.
if (const StructType *STy = dyn_cast<StructType>(OldTy))
getTargetData().InvalidateStructLayoutInfo(STy);
OldTy->removeAbstractTypeUser(this);
}
/// The other case which AbstractTypeUsers must be aware of is when a type
/// makes the transition from being abstract (where it has clients on it's
/// AbstractTypeUsers list) to concrete (where it does not). This method
/// notifies ATU's when this occurs for a type.
///
void TypeRefinementDatabase::typeBecameConcrete(const DerivedType *AbsTy) {
assert(TypeUsers.count(AbsTy) && "Not using this type!");
// Remove the type from our collection of tracked types.
TypeUsers.erase(AbsTy);
AbsTy->removeAbstractTypeUser(this);
}
void TypeRefinementDatabase::dump() const {
std::cerr << "TypeRefinementDatabase\n";
}
//===----------------------------------------------------------------------===//
// Main Type Conversion Routines
//===----------------------------------------------------------------------===//
const Type *TypeConverter::ConvertType(tree orig_type) {
if (orig_type == error_mark_node) return Type::Int32Ty;
// LLVM doesn't care about variants such as const, volatile, or restrict.
tree type = TYPE_MAIN_VARIANT(orig_type);
switch (TREE_CODE(type)) {
default:
fprintf(stderr, "Unknown type to convert:\n");
debug_tree(type);
abort();
case VOID_TYPE: return SET_TYPE_LLVM(type, Type::VoidTy);
case RECORD_TYPE: return ConvertRECORD(type, orig_type);
case UNION_TYPE: return ConvertUNION(type, orig_type);
case BOOLEAN_TYPE:
if (TREE_INT_CST_LOW(TYPE_SIZE(type)) <= 8)
return SET_TYPE_LLVM(type, Type::BoolTy);
else { // Bools on some platforms take more space than LLVM bool (e.g. PPC).
if (const Type *Ty = GET_TYPE_LLVM(type))
return Ty;
const Type *Ty = getIntegerType(TREE_INT_CST_LOW(TYPE_SIZE(type)), true);
return SET_TYPE_LLVM(type, Ty);
}
case ENUMERAL_TYPE:
// Use of an enum that is implicitly declared?
if (TYPE_SIZE(type) == 0) {
// If we already compiled this type, use the old type.
if (const Type *Ty = GET_TYPE_LLVM(type))
return Ty;
const Type *Ty = OpaqueType::get();
TheModule->addTypeName(GetTypeName("enum.", orig_type), Ty);
return TypeDB.setType(type, Ty);
}
// FALL THROUGH.
case INTEGER_TYPE:
if (const Type *Ty = GET_TYPE_LLVM(type)) return Ty;
return SET_TYPE_LLVM(type, getIntegerType(TREE_INT_CST_LOW(TYPE_SIZE(type)),
TYPE_UNSIGNED(type)));
case REAL_TYPE:
if (const Type *Ty = GET_TYPE_LLVM(type)) return Ty;
switch (TYPE_PRECISION(type)) {
default:
fprintf(stderr, "Unknown FP type!\n");
debug_tree(type);
abort();
case 32: return SET_TYPE_LLVM(type, Type::FloatTy);
case 80: // Map long doubles to doubles.
case 96: // Map long doubles to doubles.
case 64: return SET_TYPE_LLVM(type, Type::DoubleTy);
case 128:
// 128-bit long doubles map onto { double, double }.
const Type *Ty = Type::DoubleTy;
Ty = StructType::get(std::vector<const Type*>(2, Ty), false);
return SET_TYPE_LLVM(type, Ty);
}
case COMPLEX_TYPE: {
if (const Type *Ty = GET_TYPE_LLVM(type)) return Ty;
const Type *Ty = ConvertType(TREE_TYPE(type));
assert(!Ty->isAbstract() && "should use TypeDB.setType()");
Ty = StructType::get(std::vector<const Type*>(2, Ty), false);
return SET_TYPE_LLVM(type, Ty);
}
case VECTOR_TYPE: {
if (const Type *Ty = GET_TYPE_LLVM(type)) return Ty;
const Type *Ty = ConvertType(TREE_TYPE(type));
assert(!Ty->isAbstract() && "should use TypeDB.setType()");
Ty = PackedType::get(Ty, TYPE_VECTOR_SUBPARTS(type));
return SET_TYPE_LLVM(type, Ty);
}
case POINTER_TYPE:
case REFERENCE_TYPE:
if (const PointerType *Ty = cast_or_null<PointerType>(GET_TYPE_LLVM(type))){
// We already converted this type. If this isn't a case where we have to
// reparse it, just return it.
if (PointersToReresolve.empty() || PointersToReresolve.back() != type ||
ConvertingStruct)
return Ty;
// Okay, we know that we're !ConvertingStruct and that type is on the end
// of the vector. Remove this entry from the PointersToReresolve list and
// get the pointee type. Note that this order is important in case the
// pointee type uses this pointer.
assert(isa<OpaqueType>(Ty->getElementType()) && "Not a deferred ref!");
// We are actively resolving this pointer. We want to pop this value from
// the stack, as we are no longer resolving it. However, we don't want to
// make it look like we are now resolving the previous pointer on the
// stack, so pop this value and push a null.
PointersToReresolve.back() = 0;
// Do not do any nested resolution. We know that there is a higher-level
// loop processing deferred pointers, let it handle anything new.
ConvertingStruct = true;
// Note that we know that Ty cannot be resolved or invalidated here.
const Type *Actual = ConvertType(TREE_TYPE(type));
assert(GET_TYPE_LLVM(type) == Ty && "Pointer invalidated!");
// Restore ConvertingStruct for the caller.
ConvertingStruct = false;
if (Actual->getTypeID() == Type::VoidTyID)
Actual = Type::Int8Ty; // void* -> sbyte*
// Update the type, potentially updating TYPE_LLVM(type).
const OpaqueType *OT = cast<OpaqueType>(Ty->getElementType());
const_cast<OpaqueType*>(OT)->refineAbstractTypeTo(Actual);
return GET_TYPE_LLVM(type);
} else {
const Type *Ty;
// If we are converting a struct, and if we haven't converted the pointee
// type, add this pointer to PointersToReresolve and return an opaque*.
if (ConvertingStruct) {
// If the pointee type has not already been converted to LLVM, create
// a new opaque type and remember it in the database.
Ty = GET_TYPE_LLVM(TYPE_MAIN_VARIANT(TREE_TYPE(type)));
if (Ty == 0) {
PointersToReresolve.push_back(type);
return TypeDB.setType(type, PointerType::get(OpaqueType::get()));
}
// A type has already been computed. However, this may be some sort of
// recursive struct. We don't want to call ConvertType on it, because
// this will try to resolve it, and not adding the type to the
// PointerToReresolve collection is just an optimization. Instead,
// we'll use the type returned by GET_TYPE_LLVM directly, even if this
// may be resolved further in the future.
} else {
// If we're not in a struct, just call ConvertType. If it has already
// been converted, this will return the precomputed value, otherwise
// this will compute and return the new type.
Ty = ConvertType(TREE_TYPE(type));
}
if (Ty->getTypeID() == Type::VoidTyID)
Ty = Type::Int8Ty; // void* -> sbyte*
return TypeDB.setType(type, PointerType::get(Ty));
}
case METHOD_TYPE:
case FUNCTION_TYPE: {
if (const Type *Ty = GET_TYPE_LLVM(type))
return Ty;
unsigned CallingConv;
return TypeDB.setType(type, ConvertFunctionType(type, CallingConv));
}
case ARRAY_TYPE: {
if (const Type *Ty = GET_TYPE_LLVM(type))
return Ty;
unsigned NumElements;
tree Domain = TYPE_DOMAIN(type);
if (Domain && TYPE_MAX_VALUE(Domain)) {
if (TREE_CODE(TYPE_MAX_VALUE(Domain)) == INTEGER_CST) {
// Normal array.
NumElements = TREE_INT_CST_LOW(TYPE_MAX_VALUE(Domain))+1;
} else {
// This handles cases like "int A[n]" which have a runtime constant
// number of elements, but is a compile-time variable. Since these are
// variable sized, we just represent them as the element themself.
return TypeDB.setType(type, ConvertType(TREE_TYPE(type)));
}
} else {
// We get here is if they have something that is globally declared as an
// array with no dimension, this becomes just a zero size array of the
// element type so that: int X[] becomes *'%X = external global [0 x int]'
//
// Note that this also affects new expressions, which return a pointer to
// an unsized array of elements.
NumElements = 0;
}
return TypeDB.setType(type, ArrayType::get(ConvertType(TREE_TYPE(type)),
NumElements));
}
case OFFSET_TYPE:
// Handle OFFSET_TYPE specially. This is used for pointers to members,
// which are really just integer offsets. As such, return the appropriate
// integer directly.
switch (getTargetData().getPointerSize()) {
default: assert(0 && "Unknown pointer size!");
case 4: return Type::Int32Ty;
case 8: return Type::Int64Ty;
}
}
}
//===----------------------------------------------------------------------===//
// FUNCTION/METHOD_TYPE Conversion Routines
//===----------------------------------------------------------------------===//
namespace {
class FunctionTypeConversion : public DefaultABIClient {
const Type *&RetTy;
std::vector<const Type*> &ArgTypes;
unsigned &CallingConv;
public:
FunctionTypeConversion(const Type *&retty, std::vector<const Type*> &AT,
unsigned &CC)
: RetTy(retty), ArgTypes(AT), CallingConv(CC) {
CallingConv = CallingConv::C;
}
/// HandleScalarResult - This callback is invoked if the function returns a
/// simple scalar result value.
void HandleScalarResult(const Type *RetTy) {
this->RetTy = RetTy;
}
/// HandleAggregateResultAsScalar - This callback is invoked if the function
/// returns an aggregate value by bit converting it to the specified scalar
/// type and returning that.
void HandleAggregateResultAsScalar(const Type *ScalarTy) {
RetTy = ScalarTy;
}
/// HandleAggregateShadowArgument - This callback is invoked if the function
/// returns an aggregate value by using a "shadow" first parameter. If
/// RetPtr is set to true, the pointer argument itself is returned from
/// the function.
void HandleAggregateShadowArgument(const PointerType *PtrArgTy,
bool RetPtr) {
// If this function returns a structure by value, it either returns void
// or the shadow argument, depending on the target.
this->RetTy = RetPtr ? PtrArgTy : Type::VoidTy;
// In any case, there is a dummy shadow argument though!
ArgTypes.push_back(PtrArgTy);
// Also, switch the calling convention to C Struct Return.
CallingConv = CallingConv::CSRet;
}
void HandleScalarArgument(const llvm::Type *LLVMTy, tree type) {
ArgTypes.push_back(LLVMTy);
}
};
}
/// ConvertParamListToLLVMSignature - This method is used to build the argument
/// type list for K&R prototyped functions. In this case, we have to figure out
/// the type list (to build a FunctionType) from the actual DECL_ARGUMENTS list
/// for the function. This method takes the DECL_ARGUMENTS list (Args), and
/// fills in Result with the argument types for the function. It returns the
/// specified result type for the function.
const FunctionType *TypeConverter::
ConvertArgListToFnType(tree ReturnType, tree Args, unsigned &CallingConv) {
std::vector<const Type*> ArgTys;
const Type *RetTy;
FunctionTypeConversion Client(RetTy, ArgTys, CallingConv);
TheLLVMABI<FunctionTypeConversion> ABIConverter(Client);
ABIConverter.HandleReturnType(ReturnType);
for (; Args && TREE_TYPE(Args) != void_type_node; Args = TREE_CHAIN(Args))
ABIConverter.HandleArgument(TREE_TYPE(Args));
return FunctionType::get(RetTy, ArgTys, false);
}
const FunctionType *TypeConverter::ConvertFunctionType(tree type,
unsigned &CallingConv) {
const Type *RetTy = 0;
std::vector<const Type*> ArgTypes;
bool isVarArg = false;
FunctionTypeConversion Client(RetTy, ArgTypes, CallingConv);
TheLLVMABI<FunctionTypeConversion> ABIConverter(Client);
ABIConverter.HandleReturnType(TREE_TYPE(type));
// Allow the target to set the CC for things like fastcall etc.
#ifdef TARGET_ADJUST_LLVM_CC
TARGET_ADJUST_LLVM_CC(CallingConv, type);
#endif
// Loop over all of the arguments, adding them as we go.
tree Args = TYPE_ARG_TYPES(type);
for (; Args && TREE_VALUE(Args) != void_type_node; Args = TREE_CHAIN(Args)){
if (!isPassedByInvisibleReference(TREE_VALUE(Args)) &&
isa<OpaqueType>(ConvertType(TREE_VALUE(Args)))) {
// If we are passing an opaque struct by value, we don't know how many
// arguments it will turn into. Because we can't handle this yet,
// codegen the prototype as (...).
if (CallingConv == CallingConv::C)
ArgTypes.clear();
else
ArgTypes.resize(1); // Don't nuke last argument.
Args = 0;
break;
}
ABIConverter.HandleArgument(TREE_VALUE(Args));
}
// If the argument list ends with a void type node, it isn't vararg.
isVarArg = (Args == 0);
assert(RetTy && "Return type not specified!");
// If this is the C Calling Convention then scan the FunctionType's result
// type and argument types looking for integers less than 32-bits and set
// the parameter attribute in the FunctionType so any arguments passed to
// the function will be correctly sign or zero extended to 32-bits by
// the LLVM code gen.
FunctionType::ParamAttrsList ParamAttrs;
if (CallingConv == CallingConv::C || CallingConv == CallingConv::CSRet) {
tree ResultTy = TREE_TYPE(type);
if (TREE_CODE(ResultTy) == BOOLEAN_TYPE)
ParamAttrs.push_back(FunctionType::ZExtAttribute);
else if (TREE_CODE(ResultTy) == INTEGER_TYPE &&
TREE_INT_CST_LOW(TYPE_SIZE(ResultTy)) < 32)
if (TYPE_UNSIGNED(ResultTy))
ParamAttrs.push_back(FunctionType::ZExtAttribute);
else
ParamAttrs.push_back(FunctionType::SExtAttribute);
else
ParamAttrs.push_back(FunctionType::NoAttributeSet);
tree Args = TYPE_ARG_TYPES(type);
unsigned Idx = 1;
for (; Args && TREE_VALUE(Args) != void_type_node; Args = TREE_CHAIN(Args)){
tree Ty = TREE_VALUE(Args);
if (TREE_CODE(Ty) == BOOLEAN_TYPE)
ParamAttrs.push_back(FunctionType::ZExtAttribute);
else if (TREE_CODE(Ty) == INTEGER_TYPE &&
TREE_INT_CST_LOW(TYPE_SIZE(Ty)) < 32)
if (TYPE_UNSIGNED(Ty))
ParamAttrs.push_back(FunctionType::ZExtAttribute);
else
ParamAttrs.push_back(FunctionType::SExtAttribute);
else
ParamAttrs.push_back(FunctionType::NoAttributeSet);
Idx++;
}
}
return FunctionType::get(RetTy, ArgTypes, isVarArg, ParamAttrs);
}
//===----------------------------------------------------------------------===//
// RECORD/Struct Conversion Routines
//===----------------------------------------------------------------------===//
/// StructTypeConversionInfo - A temporary structure that is used when
/// translating a RECORD_TYPE to an LLVM type.
struct StructTypeConversionInfo {
std::vector<const Type*> Elements;
std::vector<uint64_t> ElementOffsetInBytes;
std::vector<uint64_t> ElementSizeInBytes;
const TargetData &TD;
unsigned GCCStructAlignmentInBytes;
StructTypeConversionInfo(TargetMachine &TM, unsigned GCCAlign)
: TD(*TM.getTargetData()), GCCStructAlignmentInBytes(GCCAlign) {}
unsigned getGCCStructAlignmentInBytes() const {
return GCCStructAlignmentInBytes;
}
/// getTypeAlignment - Return the alignment of the specified type in bytes.
///
unsigned getTypeAlignment(const Type *Ty) const {
return TD.getTypeAlignment(Ty);
}
/// getTypeSize - Return the size of the specified type in bytes.
///
unsigned getTypeSize(const Type *Ty) const {
return TD.getTypeSize(Ty);
}
/// getLLVMType - Return the LLVM type for the specified object.
///
const Type *getLLVMType() const {
return StructType::get(Elements, false);
}
/// getSizeAsLLVMStruct - Return the size of this struct if it were converted
/// to an LLVM type. This is the end of last element push an alignment pad at
/// the end.
uint64_t getSizeAsLLVMStruct() const {
if (Elements.empty()) return 0;
unsigned MaxAlign = 1;
for (unsigned i = 0, e = Elements.size(); i != e; ++i)
MaxAlign = std::max(MaxAlign, getTypeAlignment(Elements[i]));
uint64_t Size = ElementOffsetInBytes.back()+ElementSizeInBytes.back();
return (Size+MaxAlign-1) & ~(MaxAlign-1);
}
/// RemoveLastElementIfOverlapsWith - If the last element in the struct
/// includes the specified byte, remove it.
void RemoveLastElementIfOverlapsWith(uint64_t ByteOffset) {
if (Elements.empty()) return;
assert(ElementOffsetInBytes.back() <= ByteOffset &&
"Cannot go backwards in struct");
if (ElementOffsetInBytes.back()+ElementSizeInBytes.back() > ByteOffset) {
// The last element overlapped with this one, remove it.
Elements.pop_back();
ElementOffsetInBytes.pop_back();
ElementSizeInBytes.pop_back();
}
}
/// FieldNo - Remove the specified field and all of the fields that come after
/// it.
void RemoveFieldsAfter(unsigned FieldNo) {
Elements.erase(Elements.begin()+FieldNo, Elements.end());
ElementOffsetInBytes.erase(ElementOffsetInBytes.begin()+FieldNo,
ElementOffsetInBytes.end());
ElementSizeInBytes.erase(ElementSizeInBytes.begin()+FieldNo,
ElementSizeInBytes.end());
}
/// getNewElementByteOffset - If we add a new element with the specified
/// alignment, what byte offset will it land at?
unsigned getNewElementByteOffset(unsigned ByteAlignment) {
if (Elements.empty()) return 0;
uint64_t LastElementEnd =
ElementOffsetInBytes.back() + ElementSizeInBytes.back();
return (LastElementEnd+ByteAlignment-1) & ~(ByteAlignment-1);
}
/// addElement - Add an element to the structure with the specified type,
/// offset and size.
void addElement(const Type *Ty, uint64_t Offset, uint64_t Size) {
Elements.push_back(Ty);
ElementOffsetInBytes.push_back(Offset);
ElementSizeInBytes.push_back(Size);
}
/// getFieldEndOffsetInBytes - Return the byte offset of the byte immediately
/// after the specified field. For example, if FieldNo is 0 and the field
/// is 4 bytes in size, this will return 4.
unsigned getFieldEndOffsetInBytes(unsigned FieldNo) const {
assert(FieldNo < ElementOffsetInBytes.size() && "Invalid field #!");
return ElementOffsetInBytes[FieldNo]+ElementSizeInBytes[FieldNo];
}
/// getEndUnallocatedByte - Return the first byte that isn't allocated at the
/// end of a structure. For example, for {}, it's 0, for {int} it is 4, for
/// {int,short}, it is 6.
unsigned getEndUnallocatedByte() const {
if (ElementOffsetInBytes.empty()) return 0;
return getFieldEndOffsetInBytes(ElementOffsetInBytes.size()-1);
}
/// getLLVMFieldFor - When we are assigning DECL_LLVM indexes to FieldDecls,
/// this method determines which struct element to use. Since the offset of
/// the fields cannot go backwards, CurFieldNo retains the last element we
/// looked at, to keep this a nice fast linear process. If isZeroSizeField
/// is true, this should return some zero sized field that starts at the
/// specified offset.
///
/// This returns the first field that contains the specified bit.
///
unsigned getLLVMFieldFor(uint64_t FieldOffsetInBits, unsigned &CurFieldNo,
bool isZeroSizeField) {
if (!isZeroSizeField) {
// Skip over LLVM fields that start and end before the GCC field starts.
while (CurFieldNo < ElementOffsetInBytes.size() &&
getFieldEndOffsetInBytes(CurFieldNo)*8 <= FieldOffsetInBits)
++CurFieldNo;
if (CurFieldNo >= ElementOffsetInBytes.size()) return ~0U;
return CurFieldNo;
}
// Handle zero sized fields now. If the next field is zero sized, return
// it. This is a nicety that causes us to assign C fields different LLVM
// fields in cases like struct X {}; struct Y { struct X a, b, c };
if (CurFieldNo+1 < ElementOffsetInBytes.size() &&
ElementSizeInBytes[CurFieldNo+1] == 0) {
return ++CurFieldNo;
}
// Otherwise, if this is a zero sized field, return it.
if (CurFieldNo < ElementOffsetInBytes.size() &&
ElementSizeInBytes[CurFieldNo] == 0) {
return CurFieldNo;
}
// Otherwise, we couldn't find the field!
assert(0 && "Could not find field!");
return ~0U;
}
void dump() const;
};
void StructTypeConversionInfo::dump() const {
std::cerr << "Info has " << Elements.size() << " fields:\n";
for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
std::cerr << " Offset = " << ElementOffsetInBytes[i]
<< " Size = " << ElementSizeInBytes[i]
<< " Type = ";
WriteTypeSymbolic(std::cerr, Elements[i], TheModule) << "\n";
}
}
/// getFieldOffsetInBits - Return the offset (in bits) of a FIELD_DECL in a
/// structure.
static unsigned getFieldOffsetInBits(tree Field) {
assert(DECL_FIELD_BIT_OFFSET(Field) != 0 && DECL_FIELD_OFFSET(Field) != 0);
unsigned Result = TREE_INT_CST_LOW(DECL_FIELD_BIT_OFFSET(Field));
if (TREE_CODE(DECL_FIELD_OFFSET(Field)) == INTEGER_CST)
Result += TREE_INT_CST_LOW(DECL_FIELD_OFFSET(Field))*8;
return Result;
}
/// isNotLastField - Return true if this is not the last field in its record.
///
static bool isNotLastField(tree Field) {
for (Field = TREE_CHAIN(Field); Field; Field = TREE_CHAIN(Field))
if (TREE_CODE(Field) == FIELD_DECL)
return true;
return false;
}
/// DecodeStructFields - This method decodes the specified field, if it is a
/// FIELD_DECL, adding or updating the specified StructTypeConversionInfo to
/// reflect it.
void TypeConverter::DecodeStructFields(tree Field,
StructTypeConversionInfo &Info) {
if (TREE_CODE(Field) != FIELD_DECL ||
// Don't include variable sized fields, doing so would break anything
// after them... unless this is the last field.
((TYPE_SIZE(TREE_TYPE(Field)) == 0 ||
TREE_CODE(TYPE_SIZE(TREE_TYPE(Field))) != INTEGER_CST) &&
isNotLastField(Field))) return;
// Handle bit-fields specially.
if (DECL_BIT_FIELD_TYPE(Field)) {
DecodeStructBitField(Field, Info);
return;
}
// Get the starting offset in the record.
unsigned StartOffsetInBits = getFieldOffsetInBits(Field);
assert((StartOffsetInBits & 7) == 0 && "Non-bit-field has non-byte offset!");
unsigned StartOffsetInBytes = StartOffsetInBits/8;
// Pop any previous elements out of the struct if they overlap with this one.
// This can happen when the C++ front-end overlaps fields with tail padding in
// C++ classes.
Info.RemoveLastElementIfOverlapsWith(StartOffsetInBytes);
// Get the LLVM type for the field. If this field is a bitfield, use the
// declared type, not the shrunk-to-fit type that GCC gives us in TREE_TYPE.
const Type *Ty = ConvertType(TREE_TYPE(Field));
unsigned ByteAlignment = Info.getTypeAlignment(Ty);
unsigned NextByteOffset = Info.getNewElementByteOffset(ByteAlignment);
if (NextByteOffset > StartOffsetInBytes ||
ByteAlignment > Info.getGCCStructAlignmentInBytes()) {
// If the LLVM type is aligned more than the GCC type, we cannot use this
// LLVM type for the field. Instead, insert the field as an array of bytes,
// which we know will have the least alignment possible.
Ty = ArrayType::get(Type::Int8Ty, Info.getTypeSize(Ty));
ByteAlignment = 1;
NextByteOffset = Info.getNewElementByteOffset(ByteAlignment);
}
// If alignment won't round us up to the right boundary, insert explicit
// padding.
if (NextByteOffset < StartOffsetInBytes) {
unsigned CurOffset = Info.getNewElementByteOffset(1);
const Type *Pad = Type::Int8Ty;
if (StartOffsetInBytes-CurOffset != 1)
Pad = ArrayType::get(Pad, StartOffsetInBytes-CurOffset);
Info.addElement(Pad, CurOffset, StartOffsetInBytes-CurOffset);
}
// At this point, we know that adding the element will happen at the right
// offset. Add it.
Info.addElement(Ty, StartOffsetInBytes, Info.getTypeSize(Ty));
}
/// DecodeStructBitField - This method decodes the specified bit-field, adding
/// or updating the specified StructTypeConversionInfo to reflect it.
///
/// Note that in general, we cannot produce a good covering of struct fields for
/// bitfields. As such, we only make sure that all bits in a struct that
/// correspond to a bitfield are represented in the LLVM struct with
/// (potentially multiple) integer fields of integer type. This ensures that
/// initialized globals with bitfields can have the initializers for the
/// bitfields specified.
void TypeConverter::DecodeStructBitField(tree_node *Field,
StructTypeConversionInfo &Info) {
unsigned FieldSizeInBits = TREE_INT_CST_LOW(DECL_SIZE(Field));
if (FieldSizeInBits == 0) // Ignore 'int:0', which just affects layout.
return;
// Get the starting offset in the record.
unsigned StartOffsetInBits = getFieldOffsetInBits(Field);
unsigned EndBitOffset = FieldSizeInBits+StartOffsetInBits;
// If the last inserted LLVM field completely contains this bitfield, just
// ignore this field.
if (!Info.Elements.empty()) {
// If the last field does not completely contain *this* bitfield, extend
// it.
unsigned LastFieldBitOffset = Info.ElementOffsetInBytes.back()*8;
unsigned LastFieldBitSize = Info.ElementSizeInBytes.back()*8;
assert(LastFieldBitOffset < StartOffsetInBits &&
"This bitfield isn't part of the last field!");
if (EndBitOffset <= LastFieldBitOffset+LastFieldBitSize &&
LastFieldBitOffset+LastFieldBitSize >= StartOffsetInBits)
return; // Already contained in previous field!
}
// Otherwise, this bitfield lives (potentially) partially in the preceeding
// field and in fields that exist after it. Add integer-typed fields to the
// LLVM struct such that there are no holes in the struct where the bitfield
// is: these holes would make it impossible to statically initialize a global
// of this type that has an initializer for the bitfield.
// Compute the number of bits that we need to add to this struct to cover
// this field.
unsigned NumBitsToAdd = FieldSizeInBits;
unsigned FirstUnallocatedByte = Info.getEndUnallocatedByte();
// If there are any, subtract off bits that go in the previous field.
if (StartOffsetInBits < FirstUnallocatedByte*8) {
NumBitsToAdd -= FirstUnallocatedByte*8-StartOffsetInBits;
} else if (StartOffsetInBits > FirstUnallocatedByte*8) {
// If there is padding between the last field and the struct, insert
// explicit bytes into the field to represent it.
assert((StartOffsetInBits & 7) == 0 &&
"Next field starts on a non-byte boundary!");
unsigned PadBytes = StartOffsetInBits/8-FirstUnallocatedByte;
const Type *Pad = Type::Int8Ty;
if (PadBytes != 1)
Pad = ArrayType::get(Pad, PadBytes);
Info.addElement(Pad, FirstUnallocatedByte, PadBytes);
FirstUnallocatedByte = StartOffsetInBits/8;
}
// Figure out the LLVM type that we will use for the new field.
const Type *NewFieldTy;
if (NumBitsToAdd <= 8)
NewFieldTy = Type::Int8Ty;
else if (NumBitsToAdd <= 16)
NewFieldTy = Type::Int16Ty;
else if (NumBitsToAdd <= 32)
NewFieldTy = Type::Int32Ty;
else {
assert(NumBitsToAdd <= 64 && "Bitfield too large!");
NewFieldTy = Type::Int64Ty;
}
// Check that the alignment of NewFieldTy won't cause a gap in the structure!
unsigned ByteAlignment = Info.getTypeAlignment(NewFieldTy);
if (FirstUnallocatedByte & (ByteAlignment-1)) {
// Instead of inserting a nice whole field, insert a small array of ubytes.
NewFieldTy = ArrayType::get(Type::Int8Ty, (NumBitsToAdd+7)/8);
}
// Finally, add the new field.
Info.addElement(NewFieldTy, FirstUnallocatedByte,
Info.getTypeSize(NewFieldTy));
}
/// ConvertRECORD - We know that 'type' is a RECORD_TYPE: convert it to an LLVM
/// type.
const Type *TypeConverter::ConvertRECORD(tree type, tree orig_type) {
if (const Type *Ty = GET_TYPE_LLVM(type)) {
// If we already compiled this type, and if it was not a forward
// definition that is now defined, use the old type.
if (!isa<OpaqueType>(Ty) || TYPE_SIZE(type) == 0)
return Ty;
}
if (TYPE_SIZE(type) == 0) { // Forward declaration?
const Type *Ty = OpaqueType::get();
TheModule->addTypeName(GetTypeName("struct.", orig_type), Ty);
return TypeDB.setType(type, Ty);
}
// Note that we are compiling a struct now.
bool OldConvertingStruct = ConvertingStruct;
ConvertingStruct = true;
// Construct LLVM types for the base types... in order to get names for
// base classes and to ensure they are laid out.
if (tree binfo = TYPE_BINFO(type)) {
for (unsigned i = 0, e = BINFO_N_BASE_BINFOS(binfo); i != e; ++i)
ConvertType(BINFO_TYPE(BINFO_BASE_BINFO(binfo, i)));
}
StructTypeConversionInfo Info(*TheTarget, TYPE_ALIGN_UNIT(type));
// Convert over all of the elements of the struct.
for (tree Field = TYPE_FIELDS(type); Field; Field = TREE_CHAIN(Field))
DecodeStructFields(Field, Info);
// If the LLVM struct requires explicit tail padding to be the same size as
// the GCC struct, insert tail padding now. This handles, e.g., "{}" in C++.
if (TYPE_SIZE(type) && TREE_CODE(TYPE_SIZE(type)) == INTEGER_CST) {
uint64_t LLVMStructSize = Info.getSizeAsLLVMStruct();
uint64_t GCCTypeSize = ((uint64_t)TREE_INT_CST_LOW(TYPE_SIZE(type))+7)/8;
if (LLVMStructSize != GCCTypeSize) {
assert(LLVMStructSize < GCCTypeSize &&
"LLVM type size doesn't match GCC type size!");
uint64_t LLVMLastElementEnd = Info.getNewElementByteOffset(1);
const Type *PadTy = Type::Int8Ty;
if (GCCTypeSize-LLVMLastElementEnd != 1)
PadTy = ArrayType::get(PadTy, GCCTypeSize-LLVMStructSize);
Info.addElement(PadTy, GCCTypeSize-LLVMLastElementEnd,
GCCTypeSize-LLVMLastElementEnd);
}
}
// Now that the LLVM struct is finalized, figure out a safe place to index to
// and set the DECL_LLVM values for each FieldDecl that doesn't start at a
// variable offset.
unsigned CurFieldNo = 0;
for (tree Field = TYPE_FIELDS(type); Field; Field = TREE_CHAIN(Field))
if (TREE_CODE(Field) == FIELD_DECL) {
// If this field comes after a variable sized element, stop trying to
// assign DECL_LLVM's.
if (TREE_CODE(DECL_FIELD_OFFSET(Field)) != INTEGER_CST)
break;
unsigned FieldOffsetInBits = getFieldOffsetInBits(Field);
tree FieldType = TREE_TYPE(Field);
// If this is a bitfield, we may want to adjust the FieldOffsetInBits to
// produce safe code. In particular, bitfields will be loaded/stored as
// their *declared* type, not the smallest integer type that contains
// them. As such, we need to respect the alignment of the declared type.
if (tree DeclaredType = DECL_BIT_FIELD_TYPE(Field)) {
// If this is a bitfield, the declared type must be an integral type.
const Type *DeclFieldTy = ConvertType(DeclaredType);
unsigned DeclBitAlignment = Info.getTypeAlignment(DeclFieldTy)*8;
FieldOffsetInBits &= ~(DeclBitAlignment-1ULL);
}
// Figure out if this field is zero bits wide, e.g. {} or [0 x int]. Do
// not include variable sized fields here.
bool isZeroSizeField =
TYPE_SIZE(FieldType) && TREE_CODE(TYPE_SIZE(FieldType)) == INTEGER_CST&&
TREE_INT_CST_LOW(TYPE_SIZE(FieldType)) == 0;
unsigned FieldNo =
Info.getLLVMFieldFor(FieldOffsetInBits, CurFieldNo, isZeroSizeField);
SET_DECL_LLVM(Field, ConstantInt::get(Type::Int32Ty, FieldNo));
}
const Type *ResultTy = Info.getLLVMType();
const OpaqueType *OldTy = cast_or_null<OpaqueType>(GET_TYPE_LLVM(type));
TypeDB.setType(type, ResultTy);
// If there was a forward declaration for this type that is now resolved,
// refine anything that used it to the new type.
if (OldTy)
const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
// Finally, set the name for the type.
TheModule->addTypeName(GetTypeName("struct.", orig_type),
GET_TYPE_LLVM(type));
// We have finished converting this struct. See if the is the outer-most
// struct being converted by ConvertType.
ConvertingStruct = OldConvertingStruct;
if (!ConvertingStruct) {
// If this is the outer-most level of structness, resolve any pointers
// that were deferred.
while (!PointersToReresolve.empty()) {
if (tree PtrTy = PointersToReresolve.back()) {
ConvertType(PtrTy); // Reresolve this pointer type.
assert((PointersToReresolve.empty() ||
PointersToReresolve.back() != PtrTy) &&
"Something went wrong with pointer resolution!");
} else {
// Null marker element.
PointersToReresolve.pop_back();
}
}
}
return GET_TYPE_LLVM(type);
}
/// ConvertUNION - We know that 'type' is a UNION_TYPE: convert it to an LLVM
/// type.
const Type *TypeConverter::ConvertUNION(tree type, tree orig_type) {
if (const Type *Ty = GET_TYPE_LLVM(type)) {
// If we already compiled this type, and if it was not a forward
// definition that is now defined, use the old type.
if (!isa<OpaqueType>(Ty) || TYPE_SIZE(type) == 0)
return Ty;
}
if (TYPE_SIZE(type) == 0) { // Forward declaraion?
const Type *Ty = OpaqueType::get();
TheModule->addTypeName(GetTypeName("union.", orig_type), Ty);
return TypeDB.setType(type, Ty);
}
// If this is a union with the transparent_union attribute set, it is
// treated as if it were just the same as its first type.
if (TYPE_TRANSPARENT_UNION(type)) {
tree Field = TYPE_FIELDS(type);
assert(Field && "Transparent union must have some elements!");
while (TREE_CODE(Field) != FIELD_DECL) {
Field = TREE_CHAIN(Field);
assert(Field && "Transparent union must have some elements!");
}
return TypeDB.setType(type, ConvertType(TREE_TYPE(Field)));
}
// Note that we are compiling a struct now.
bool OldConvertingStruct = ConvertingStruct;
ConvertingStruct = true;
// Find the type with the largest size, and if we have multiple things with
// the same size, the thing with the largest alignment.
const TargetData &TD = getTargetData();
const Type *UnionTy = 0;
unsigned MaxSize = 0, MaxAlign = 0;
Value *Idx = Constant::getNullValue(Type::Int32Ty);
for (tree Field = TYPE_FIELDS(type); Field; Field = TREE_CHAIN(Field)) {
if (TREE_CODE(Field) != FIELD_DECL) continue;
assert(getFieldOffsetInBits(Field) == 0 && "Union with non-zero offset?");
// Set the field idx to zero for all fields.
SET_DECL_LLVM(Field, Idx);
const Type *TheTy = ConvertType(TREE_TYPE(Field));
unsigned Size = TD.getTypeSize(TheTy);
unsigned Align = TD.getTypeAlignment(TheTy);
if (UnionTy == 0 || Size>MaxSize || (Size == MaxSize && Align > MaxAlign)) {
UnionTy = TheTy;
MaxSize = Size;
MaxAlign = Align;
}
}
std::vector<const Type*> UnionElts;
unsigned UnionSize = 0;
if (UnionTy) { // Not an empty union.
UnionSize = TD.getTypeSize(UnionTy);
UnionElts.push_back(UnionTy);
}
// If the LLVM struct requires explicit tail padding to be the same size as
// the GCC union, insert tail padding now. This handles cases where the union
// has larger alignment than the largest member does, thus requires tail
// padding.
if (TYPE_SIZE(type) && TREE_CODE(TYPE_SIZE(type)) == INTEGER_CST) {
unsigned GCCTypeSize = ((unsigned)TREE_INT_CST_LOW(TYPE_SIZE(type))+7)/8;
if (UnionSize != GCCTypeSize) {
assert(UnionSize < GCCTypeSize &&
"LLVM type size doesn't match GCC type size!");
const Type *PadTy = Type::Int8Ty;
if (GCCTypeSize-UnionSize != 1)
PadTy = ArrayType::get(PadTy, GCCTypeSize-UnionSize);
UnionElts.push_back(PadTy);
}
}
// If this is an empty union, but there is tail padding, make a filler.
if (UnionTy == 0) {
unsigned Size = ((unsigned)TREE_INT_CST_LOW(TYPE_SIZE(type))+7)/8;
UnionTy = Type::Int8Ty;
if (Size != 1) UnionTy = ArrayType::get(UnionTy, Size);
}
const Type *ResultTy = StructType::get(UnionElts, false);
const OpaqueType *OldTy = cast_or_null<OpaqueType>(GET_TYPE_LLVM(type));
TypeDB.setType(type, ResultTy);
// If there was a forward declaration for this type that is now resolved,
// refine anything that used it to the new type.
if (OldTy)
const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
// Finally, set the name for the type.
TheModule->addTypeName(GetTypeName("struct.", orig_type),
GET_TYPE_LLVM(type));
// We have finished converting this union. See if the is the outer-most
// union being converted by ConvertType.
ConvertingStruct = OldConvertingStruct;
if (!ConvertingStruct) {
// If this is the outer-most level of structness, resolve any pointers
// that were deferred.
while (!PointersToReresolve.empty()) {
if (tree PtrTy = PointersToReresolve.back()) {
ConvertType(PtrTy); // Reresolve this pointer type.
assert((PointersToReresolve.empty() ||
PointersToReresolve.back() != PtrTy) &&
"Something went wrong with pointer resolution!");
} else {
// Null marker element.
PointersToReresolve.pop_back();
}
}
}
return GET_TYPE_LLVM(type);
}
/* APPLE LOCAL end LLVM (ENTIRE FILE!) */
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