llvm-6502/lib/VMCore/ConstantFold.cpp
Chris Lattner 311611079b * Support global constants
* Eliminate need for constant pool


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@451 91177308-0d34-0410-b5e6-96231b3b80d8
2001-09-07 16:40:34 +00:00

273 lines
11 KiB
C++

//===- ConstantHandling.cpp - Implement ConstantHandling.h ----------------===//
//
// This file implements the various intrinsic operations, on constant values.
//
//===----------------------------------------------------------------------===//
#include "llvm/Optimizations/ConstantHandling.h"
namespace opt {
//===----------------------------------------------------------------------===//
// TemplateRules Class
//===----------------------------------------------------------------------===//
//
// TemplateRules - Implement a subclass of ConstRules that provides all
// operations as noops. All other rules classes inherit from this class so
// that if functionality is needed in the future, it can simply be added here
// and to ConstRules without changing anything else...
//
// This class also provides subclasses with typesafe implementations of methods
// so that don't have to do type casting.
//
template<class ArgType, class SubClassName>
class TemplateRules : public ConstRules {
//===--------------------------------------------------------------------===//
// Redirecting functions that cast to the appropriate types
//===--------------------------------------------------------------------===//
virtual ConstPoolVal *not(const ConstPoolVal *V) const {
return SubClassName::Not((const ArgType *)V);
}
virtual ConstPoolVal *add(const ConstPoolVal *V1,
const ConstPoolVal *V2) const {
return SubClassName::Add((const ArgType *)V1, (const ArgType *)V2);
}
virtual ConstPoolVal *sub(const ConstPoolVal *V1,
const ConstPoolVal *V2) const {
return SubClassName::Sub((const ArgType *)V1, (const ArgType *)V2);
}
virtual ConstPoolVal *mul(const ConstPoolVal *V1,
const ConstPoolVal *V2) const {
return SubClassName::Mul((const ArgType *)V1, (const ArgType *)V2);
}
virtual ConstPoolBool *lessthan(const ConstPoolVal *V1,
const ConstPoolVal *V2) const {
return SubClassName::LessThan((const ArgType *)V1, (const ArgType *)V2);
}
// Casting operators. ick
virtual ConstPoolBool *castToBool(const ConstPoolVal *V) const {
return SubClassName::CastToBool((const ArgType*)V);
}
virtual ConstPoolSInt *castToSByte(const ConstPoolVal *V) const {
return SubClassName::CastToSByte((const ArgType*)V);
}
virtual ConstPoolUInt *castToUByte(const ConstPoolVal *V) const {
return SubClassName::CastToUByte((const ArgType*)V);
}
virtual ConstPoolSInt *castToShort(const ConstPoolVal *V) const {
return SubClassName::CastToShort((const ArgType*)V);
}
virtual ConstPoolUInt *castToUShort(const ConstPoolVal *V) const {
return SubClassName::CastToUShort((const ArgType*)V);
}
virtual ConstPoolSInt *castToInt(const ConstPoolVal *V) const {
return SubClassName::CastToInt((const ArgType*)V);
}
virtual ConstPoolUInt *castToUInt(const ConstPoolVal *V) const {
return SubClassName::CastToUInt((const ArgType*)V);
}
virtual ConstPoolSInt *castToLong(const ConstPoolVal *V) const {
return SubClassName::CastToLong((const ArgType*)V);
}
virtual ConstPoolUInt *castToULong(const ConstPoolVal *V) const {
return SubClassName::CastToULong((const ArgType*)V);
}
virtual ConstPoolFP *castToFloat(const ConstPoolVal *V) const {
return SubClassName::CastToFloat((const ArgType*)V);
}
virtual ConstPoolFP *castToDouble(const ConstPoolVal *V) const {
return SubClassName::CastToDouble((const ArgType*)V);
}
//===--------------------------------------------------------------------===//
// Default "noop" implementations
//===--------------------------------------------------------------------===//
inline static ConstPoolVal *Not(const ArgType *V) { return 0; }
inline static ConstPoolVal *Add(const ArgType *V1, const ArgType *V2) {
return 0;
}
inline static ConstPoolVal *Sub(const ArgType *V1, const ArgType *V2) {
return 0;
}
inline static ConstPoolVal *Mul(const ArgType *V1, const ArgType *V2) {
return 0;
}
inline static ConstPoolBool *LessThan(const ArgType *V1, const ArgType *V2) {
return 0;
}
// Casting operators. ick
inline static ConstPoolBool *CastToBool (const ConstPoolVal *V) { return 0; }
inline static ConstPoolSInt *CastToSByte (const ConstPoolVal *V) { return 0; }
inline static ConstPoolUInt *CastToUByte (const ConstPoolVal *V) { return 0; }
inline static ConstPoolSInt *CastToShort (const ConstPoolVal *V) { return 0; }
inline static ConstPoolUInt *CastToUShort(const ConstPoolVal *V) { return 0; }
inline static ConstPoolSInt *CastToInt (const ConstPoolVal *V) { return 0; }
inline static ConstPoolUInt *CastToUInt (const ConstPoolVal *V) { return 0; }
inline static ConstPoolSInt *CastToLong (const ConstPoolVal *V) { return 0; }
inline static ConstPoolUInt *CastToULong (const ConstPoolVal *V) { return 0; }
inline static ConstPoolFP *CastToFloat (const ConstPoolVal *V) { return 0; }
inline static ConstPoolFP *CastToDouble(const ConstPoolVal *V) { return 0; }
};
//===----------------------------------------------------------------------===//
// EmptyRules Class
//===----------------------------------------------------------------------===//
//
// EmptyRules provides a concrete base class of ConstRules that does nothing
//
static // EmptyInst is static
struct EmptyRules : public TemplateRules<ConstPoolVal, EmptyRules> {
} EmptyInst;
//===----------------------------------------------------------------------===//
// BoolRules Class
//===----------------------------------------------------------------------===//
//
// BoolRules provides a concrete base class of ConstRules for the 'bool' type.
//
static // BoolTyInst is static...
struct BoolRules : public TemplateRules<ConstPoolBool, BoolRules> {
inline static ConstPoolVal *Not(const ConstPoolBool *V) {
return ConstPoolBool::get(!V->getValue());
}
inline static ConstPoolVal *Or(const ConstPoolBool *V1,
const ConstPoolBool *V2) {
return ConstPoolBool::get(V1->getValue() | V2->getValue());
}
inline static ConstPoolVal *And(const ConstPoolBool *V1,
const ConstPoolBool *V2) {
return ConstPoolBool::get(V1->getValue() & V2->getValue());
}
} BoolTyInst;
//===----------------------------------------------------------------------===//
// DirectRules Class
//===----------------------------------------------------------------------===//
//
// DirectRules provides a concrete base classes of ConstRules for a variety of
// different types. This allows the C++ compiler to automatically generate our
// constant handling operations in a typesafe and accurate manner.
//
template<class ConstPoolClass, class BuiltinType, const Type **Ty>
struct DirectRules
: public TemplateRules<ConstPoolClass,
DirectRules<ConstPoolClass, BuiltinType, Ty> > {
inline static ConstPoolVal *Not(const ConstPoolClass *V) {
return ConstPoolClass::get(*Ty, !(BuiltinType)V->getValue());;
}
inline static ConstPoolVal *Add(const ConstPoolClass *V1,
const ConstPoolClass *V2) {
BuiltinType Result = (BuiltinType)V1->getValue() +
(BuiltinType)V2->getValue();
return ConstPoolClass::get(*Ty, Result);
}
inline static ConstPoolVal *Sub(const ConstPoolClass *V1,
const ConstPoolClass *V2) {
BuiltinType Result = (BuiltinType)V1->getValue() -
(BuiltinType)V2->getValue();
return ConstPoolClass::get(*Ty, Result);
}
inline static ConstPoolVal *Mul(const ConstPoolClass *V1,
const ConstPoolClass *V2) {
BuiltinType Result = (BuiltinType)V1->getValue() *
(BuiltinType)V2->getValue();
return ConstPoolClass::get(*Ty, Result);
}
inline static ConstPoolBool *LessThan(const ConstPoolClass *V1,
const ConstPoolClass *V2) {
bool Result = (BuiltinType)V1->getValue() < (BuiltinType)V2->getValue();
return ConstPoolBool::get(Result);
}
// Casting operators. ick
#define DEF_CAST(TYPE, CLASS, CTYPE) \
inline static CLASS *CastTo##TYPE (const ConstPoolClass *V) { \
return CLASS::get(Type::TYPE##Ty, (CTYPE)(BuiltinType)V->getValue()); \
}
DEF_CAST(Bool , ConstPoolBool, bool)
DEF_CAST(SByte , ConstPoolSInt, signed char)
DEF_CAST(UByte , ConstPoolUInt, unsigned char)
DEF_CAST(Short , ConstPoolSInt, signed short)
DEF_CAST(UShort, ConstPoolUInt, unsigned short)
DEF_CAST(Int , ConstPoolSInt, signed int)
DEF_CAST(UInt , ConstPoolUInt, unsigned int)
DEF_CAST(Long , ConstPoolSInt, int64_t)
DEF_CAST(ULong , ConstPoolUInt, uint64_t)
DEF_CAST(Float , ConstPoolFP , float)
DEF_CAST(Double, ConstPoolFP , double)
#undef DEF_CAST
};
//===----------------------------------------------------------------------===//
// DirectRules Subclasses
//===----------------------------------------------------------------------===//
//
// Given the DirectRules class we can now implement lots of types with little
// code. Thank goodness C++ compilers are great at stomping out layers of
// templates... can you imagine having to do this all by hand? (/me is lazy :)
//
static DirectRules<ConstPoolSInt, signed char , &Type::SByteTy> SByteTyInst;
static DirectRules<ConstPoolUInt, unsigned char , &Type::UByteTy> UByteTyInst;
static DirectRules<ConstPoolSInt, signed short, &Type::ShortTy> ShortTyInst;
static DirectRules<ConstPoolUInt, unsigned short, &Type::UShortTy> UShortTyInst;
static DirectRules<ConstPoolSInt, signed int , &Type::IntTy> IntTyInst;
static DirectRules<ConstPoolUInt, unsigned int , &Type::UIntTy> UIntTyInst;
static DirectRules<ConstPoolSInt, int64_t , &Type::LongTy> LongTyInst;
static DirectRules<ConstPoolUInt, uint64_t , &Type::ULongTy> ULongTyInst;
static DirectRules<ConstPoolFP , float , &Type::FloatTy> FloatTyInst;
static DirectRules<ConstPoolFP , double , &Type::DoubleTy> DoubleTyInst;
// ConstRules::find - Return the constant rules that take care of the specified
// type. Note that this is cached in the Type value itself, so switch statement
// is only hit at most once per type.
//
const ConstRules *ConstRules::find(const Type *Ty) {
const ConstRules *Result;
switch (Ty->getPrimitiveID()) {
case Type::BoolTyID: Result = &BoolTyInst; break;
case Type::SByteTyID: Result = &SByteTyInst; break;
case Type::UByteTyID: Result = &UByteTyInst; break;
case Type::ShortTyID: Result = &ShortTyInst; break;
case Type::UShortTyID: Result = &UShortTyInst; break;
case Type::IntTyID: Result = &IntTyInst; break;
case Type::UIntTyID: Result = &UIntTyInst; break;
case Type::LongTyID: Result = &LongTyInst; break;
case Type::ULongTyID: Result = &ULongTyInst; break;
case Type::FloatTyID: Result = &FloatTyInst; break;
case Type::DoubleTyID: Result = &DoubleTyInst; break;
default: Result = &EmptyInst; break;
}
Ty->setConstRules(Result); // Cache the value for future short circuiting!
return Result;
}
} // End namespace opt