-//===-- llvm/Target/TargetData.h - Data size & alignment routines-*- C++ -*-==//
+//===-- llvm/Target/TargetData.h - Data size & alignment info ---*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file defines target properties related to datatype size/offset/alignment
-// information. It uses lazy annotations to cache information about how
+// information. It uses lazy annotations to cache information about how
// structure types are laid out and used.
//
// This structure should be created once, filled in if the defaults are not
#ifndef LLVM_TARGET_TARGETDATA_H
#define LLVM_TARGET_TARGETDATA_H
-#include "llvm/Type.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/DataTypes.h"
+#include "llvm/ADT/SmallVector.h"
+#include <string>
+namespace llvm {
+
+class Value;
+class Type;
class StructType;
class StructLayout;
+class GlobalVariable;
+
+/// Enum used to categorize the alignment types stored by TargetAlignElem
+enum AlignTypeEnum {
+ INTEGER_ALIGN = 'i', ///< Integer type alignment
+ VECTOR_ALIGN = 'v', ///< Vector type alignment
+ FLOAT_ALIGN = 'f', ///< Floating point type alignment
+ AGGREGATE_ALIGN = 'a', ///< Aggregate alignment
+ STACK_ALIGN = 's' ///< Stack objects alignment
+};
+/// Target alignment element.
+///
+/// Stores the alignment data associated with a given alignment type (pointer,
+/// integer, vector, float) and type bit width.
+///
+/// @note The unusual order of elements in the structure attempts to reduce
+/// padding and make the structure slightly more cache friendly.
+struct TargetAlignElem {
+ AlignTypeEnum AlignType : 8; //< Alignment type (AlignTypeEnum)
+ unsigned char ABIAlign; //< ABI alignment for this type/bitw
+ unsigned char PrefAlign; //< Pref. alignment for this type/bitw
+ uint32_t TypeBitWidth; //< Type bit width
+
+ /// Initializer
+ static TargetAlignElem get(AlignTypeEnum align_type, unsigned char abi_align,
+ unsigned char pref_align, uint32_t bit_width);
+ /// Equality predicate
+ bool operator==(const TargetAlignElem &rhs) const;
+ /// output stream operator
+ std::ostream &dump(std::ostream &os) const;
+};
+
+class TargetData : public ImmutablePass {
+private:
+ bool LittleEndian; ///< Defaults to false
+ unsigned char PointerMemSize; ///< Pointer size in bytes
+ unsigned char PointerABIAlign; ///< Pointer ABI alignment
+ unsigned char PointerPrefAlign; ///< Pointer preferred alignment
+
+ //! Where the primitive type alignment data is stored.
+ /*!
+ @sa init().
+ @note Could support multiple size pointer alignments, e.g., 32-bit pointers
+ vs. 64-bit pointers by extending TargetAlignment, but for now, we don't.
+ */
+ SmallVector<TargetAlignElem, 16> Alignments;
+ //! Alignment iterator shorthand
+ typedef SmallVector<TargetAlignElem, 16>::iterator align_iterator;
+ //! Constant alignment iterator shorthand
+ typedef SmallVector<TargetAlignElem, 16>::const_iterator align_const_iterator;
+ //! Invalid alignment.
+ /*!
+ This member is a signal that a requested alignment type and bit width were
+ not found in the SmallVector.
+ */
+ static const TargetAlignElem InvalidAlignmentElem;
+
+ //! Set/initialize target alignments
+ void setAlignment(AlignTypeEnum align_type, unsigned char abi_align,
+ unsigned char pref_align, uint32_t bit_width);
+ unsigned getAlignmentInfo(AlignTypeEnum align_type, uint32_t bit_width,
+ bool ABIAlign, const Type *Ty) const;
+ //! Internal helper method that returns requested alignment for type.
+ unsigned char getAlignment(const Type *Ty, bool abi_or_pref) const;
+
+ /// Valid alignment predicate.
+ ///
+ /// Predicate that tests a TargetAlignElem reference returned by get() against
+ /// InvalidAlignmentElem.
+ inline bool validAlignment(const TargetAlignElem &align) const {
+ return (&align != &InvalidAlignmentElem);
+ }
-class TargetData {
- unsigned char ByteAlignment; // Defaults to 1 bytes
- unsigned char ShortAlignment; // Defaults to 2 bytes
- unsigned char IntAlignment; // Defaults to 4 bytes
- unsigned char LongAlignment; // Defaults to 8 bytes
- unsigned char FloatAlignment; // Defaults to 4 bytes
- unsigned char DoubleAlignment; // Defaults to 8 bytes
- unsigned char PointerSize; // Defaults to 8 bytes
- unsigned char PointerAlignment; // Defaults to 8 bytes
- AnnotationID AID; // AID for structure layout annotation
-
- static Annotation *TypeAnFactory(AnnotationID, const Annotable *, void *);
public:
- TargetData(const string &TargetName, unsigned char PtrSize = 8,
- unsigned char PtrAl = 8, unsigned char DoubleAl = 8,
- unsigned char FloatAl = 4, unsigned char LongAl = 8,
- unsigned char IntAl = 4, unsigned char ShortAl = 2,
- unsigned char ByteAl = 1);
+ /// Default ctor.
+ ///
+ /// @note This has to exist, because this is a pass, but it should never be
+ /// used.
+ TargetData() : ImmutablePass(intptr_t(&ID)) {
+ assert(0 && "ERROR: Bad TargetData ctor used. "
+ "Tool did not specify a TargetData to use?");
+ abort();
+ }
+
+ /// Constructs a TargetData from a specification string. See init().
+ explicit TargetData(const std::string &TargetDescription)
+ : ImmutablePass(intptr_t(&ID)) {
+ init(TargetDescription);
+ }
+
+ /// Initialize target data from properties stored in the module.
+ explicit TargetData(const Module *M);
+
+ TargetData(const TargetData &TD) :
+ ImmutablePass(intptr_t(&ID)),
+ LittleEndian(TD.isLittleEndian()),
+ PointerMemSize(TD.PointerMemSize),
+ PointerABIAlign(TD.PointerABIAlign),
+ PointerPrefAlign(TD.PointerPrefAlign),
+ Alignments(TD.Alignments)
+ { }
+
~TargetData(); // Not virtual, do not subclass this class
- unsigned char getByteAlignment() const { return ByteAlignment; }
- unsigned char getShortAlignment() const { return ShortAlignment; }
- unsigned char getIntAlignment() const { return IntAlignment; }
- unsigned char getLongAlignment() const { return LongAlignment; }
- unsigned char getFloatAlignment() const { return FloatAlignment; }
- unsigned char getDoubleAlignment() const { return DoubleAlignment; }
- unsigned char getPointerAlignment() const { return PointerAlignment; }
- unsigned char getPointerSize() const { return PointerSize; }
- AnnotationID getStructLayoutAID() const { return AID; }
-
- // getTypeSize - Return the number of bytes neccesary to hold the specified
- // type
- unsigned getTypeSize (const Type *Ty) const;
-
- // getTypeAlignment - Return the minimum required alignment for the specified
- // type
- unsigned char getTypeAlignment(const Type *Ty) const;
-
- // getIndexOffset - return the offset from the beginning of the type for the
- // specified indices. This is used to implement getElementPtr and load and
- // stores that include the implicit form of getelementptr.
- //
- unsigned getIndexedOffset(const Type *Ty,
- const vector<ConstPoolVal*> &Indices) const;
-
- inline const StructLayout *getStructLayout(const StructType *Ty) const {
- return (const StructLayout*)((const Type*)Ty)->getOrCreateAnnotation(AID);
+ //! Parse a target data layout string and initialize TargetData alignments.
+ void init(const std::string &TargetDescription);
+
+ /// Target endianness...
+ bool isLittleEndian() const { return LittleEndian; }
+ bool isBigEndian() const { return !LittleEndian; }
+
+ /// getStringRepresentation - Return the string representation of the
+ /// TargetData. This representation is in the same format accepted by the
+ /// string constructor above.
+ std::string getStringRepresentation() const;
+ /// Target pointer alignment
+ unsigned char getPointerABIAlignment() const { return PointerABIAlign; }
+ /// Return target's alignment for stack-based pointers
+ unsigned char getPointerPrefAlignment() const { return PointerPrefAlign; }
+ /// Target pointer size
+ unsigned char getPointerSize() const { return PointerMemSize; }
+ /// Target pointer size, in bits
+ unsigned char getPointerSizeInBits() const { return 8*PointerMemSize; }
+
+ /// getTypeSizeInBits - Return the number of bits necessary to hold the
+ /// specified type. For example, returns 36 for i36 and 80 for x86_fp80.
+ uint64_t getTypeSizeInBits(const Type* Ty) const;
+
+ /// getTypeStoreSize - Return the maximum number of bytes that may be
+ /// overwritten by storing the specified type. For example, returns 5
+ /// for i36 and 10 for x86_fp80.
+ uint64_t getTypeStoreSize(const Type *Ty) const {
+ return (getTypeSizeInBits(Ty)+7)/8;
+ }
+
+ /// getTypeStoreSizeInBits - Return the maximum number of bits that may be
+ /// overwritten by storing the specified type; always a multiple of 8. For
+ /// example, returns 40 for i36 and 80 for x86_fp80.
+ uint64_t getTypeStoreSizeInBits(const Type *Ty) const {
+ return 8*getTypeStoreSize(Ty);
+ }
+
+ /// getABITypeSize - Return the offset in bytes between successive objects
+ /// of the specified type, including alignment padding. This is the amount
+ /// that alloca reserves for this type. For example, returns 12 or 16 for
+ /// x86_fp80, depending on alignment.
+ uint64_t getABITypeSize(const Type* Ty) const {
+ unsigned char Align = getABITypeAlignment(Ty);
+ return (getTypeStoreSize(Ty) + Align - 1)/Align*Align;
}
+
+ /// getABITypeSizeInBits - Return the offset in bits between successive
+ /// objects of the specified type, including alignment padding; always a
+ /// multiple of 8. This is the amount that alloca reserves for this type.
+ /// For example, returns 96 or 128 for x86_fp80, depending on alignment.
+ uint64_t getABITypeSizeInBits(const Type* Ty) const {
+ return 8*getABITypeSize(Ty);
+ }
+
+ /// getABITypeAlignment - Return the minimum ABI-required alignment for the
+ /// specified type.
+ unsigned char getABITypeAlignment(const Type *Ty) const;
+
+ /// getCallFrameTypeAlignment - Return the minimum ABI-required alignment
+ /// for the specified type when it is part of a call frame.
+ unsigned char getCallFrameTypeAlignment(const Type *Ty) const;
+
+
+ /// getPrefTypeAlignment - Return the preferred stack/global alignment for
+ /// the specified type. This is always at least as good as the ABI alignment.
+ unsigned char getPrefTypeAlignment(const Type *Ty) const;
+
+ /// getPreferredTypeAlignmentShift - Return the preferred alignment for the
+ /// specified type, returned as log2 of the value (a shift amount).
+ ///
+ unsigned char getPreferredTypeAlignmentShift(const Type *Ty) const;
+
+ /// getIntPtrType - Return an unsigned integer type that is the same size or
+ /// greater to the host pointer size.
+ ///
+ const Type *getIntPtrType() const;
+
+ /// getIndexedOffset - return the offset from the beginning of the type for the
+ /// specified indices. This is used to implement getelementptr.
+ ///
+ uint64_t getIndexedOffset(const Type *Ty,
+ Value* const* Indices, unsigned NumIndices) const;
+
+ /// getStructLayout - Return a StructLayout object, indicating the alignment
+ /// of the struct, its size, and the offsets of its fields. Note that this
+ /// information is lazily cached.
+ const StructLayout *getStructLayout(const StructType *Ty) const;
+
+ /// InvalidateStructLayoutInfo - TargetData speculatively caches StructLayout
+ /// objects. If a TargetData object is alive when types are being refined and
+ /// removed, this method must be called whenever a StructType is removed to
+ /// avoid a dangling pointer in this cache.
+ void InvalidateStructLayoutInfo(const StructType *Ty) const;
+
+ /// getPreferredAlignment - Return the preferred alignment of the specified
+ /// global. This includes an explicitly requested alignment (if the global
+ /// has one).
+ unsigned getPreferredAlignment(const GlobalVariable *GV) const;
+
+ /// getPreferredAlignmentLog - Return the preferred alignment of the
+ /// specified global, returned in log form. This includes an explicitly
+ /// requested alignment (if the global has one).
+ unsigned getPreferredAlignmentLog(const GlobalVariable *GV) const;
+
+ static char ID; // Pass identification, replacement for typeid
};
-// This annotation (attached ONLY to StructType classes) is used to lazily
-// calculate structure layout information for a target machine, based on the
-// TargetData structure.
-//
-struct StructLayout : public Annotation {
- vector<unsigned> MemberOffsets;
- unsigned StructSize;
+/// StructLayout - used to lazily calculate structure layout information for a
+/// target machine, based on the TargetData structure.
+///
+class StructLayout {
+ uint64_t StructSize;
unsigned StructAlignment;
+ unsigned NumElements;
+ uint64_t MemberOffsets[1]; // variable sized array!
+public:
+
+ uint64_t getSizeInBytes() const {
+ return StructSize;
+ }
+
+ uint64_t getSizeInBits() const {
+ return 8*StructSize;
+ }
+
+ unsigned getAlignment() const {
+ return StructAlignment;
+ }
+
+ /// getElementContainingOffset - Given a valid offset into the structure,
+ /// return the structure index that contains it.
+ ///
+ unsigned getElementContainingOffset(uint64_t Offset) const;
+
+ uint64_t getElementOffset(unsigned Idx) const {
+ assert(Idx < NumElements && "Invalid element idx!");
+ return MemberOffsets[Idx];
+ }
+
+ uint64_t getElementOffsetInBits(unsigned Idx) const {
+ return getElementOffset(Idx)*8;
+ }
+
private:
friend class TargetData; // Only TargetData can create this class
- inline StructLayout(const StructType *ST, const TargetData &TD);
+ StructLayout(const StructType *ST, const TargetData &TD);
};
+} // End llvm namespace
+
#endif