Newer
Older
// $Id$
//***************************************************************************
// File:
// TargetMachine.cpp
//
// Purpose:
//
// History:
// 7/12/01 - Vikram Adve - Created
//**************************************************************************/
//************************** System Include Files **************************/
//*************************** User Include Files ***************************/
#include "llvm/DerivedTypes.h"
#include "llvm/CodeGen/TargetMachine.h"
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
//************************* Opaque Declarations ****************************/
class StructType;
class MachineInstrInfo;
//************************ Class Implementations **************************/
//---------------------------------------------------------------------------
// function TargetMachine::findOptimalMemberOffsets
//
// Purpose:
// Compute optimal offsets for the members of a structure.
// Returns a vector of unsigned ints, one per member.
// Caller is responsible for freeing the vector.
//---------------------------------------------------------------------------
unsigned int
TargetMachine::findOptimalStorageSize(const Type* ty) const
{
switch(ty->getPrimitiveID())
{
case Type::BoolTyID:
case Type::UByteTyID: case Type::SByteTyID:
case Type::UShortTyID: case Type::ShortTyID:
return optSizeForSubWordData;
break;
case Type::UIntTyID: case Type::IntTyID:
return intSize;
break;
case Type::FloatTyID:
return floatSize;
break;
case Type::ULongTyID: case Type::LongTyID:
return longSize;
break;
case Type::DoubleTyID:
return doubleSize;
break;
case Type::PointerTyID:
case Type::LabelTyID: case Type::MethodTyID:
return pointerSize;
break;
case Type::ArrayTyID:
{
ArrayType* aty = (ArrayType*) ty;
assert(aty->getNumElements() >= 0 &&
"Attempting to compute size for unknown-size array");
return (unsigned) aty->getNumElements() *
this->findOptimalStorageSize(aty->getElementType());
break;
}
case Type::StructTyID:
{// This code should be invoked only from StructType::getStorageSize().
StructType* sty = (StructType*) ty;
unsigned lastMemberIdx = sty->getElementTypes().size() - 1;
unsigned lastMemberOffset = sty->getElementOffset(lastMemberIdx, *this);
unsigned storageSize = lastMemberOffset
+ this->findOptimalStorageSize(sty->getElementTypes()[lastMemberIdx]);
return storageSize;
break;
}
default:
assert(0 && "Unexpected type in `findOptimalStorageSize'");
return 0;
break;
}
}
unsigned int*
TargetMachine::findOptimalMemberOffsets(const StructType* stype) const
{
int numMembers = stype->getElementTypes().size();
unsigned int* offsetVec = new unsigned int[numMembers];
unsigned int netOffset = 0;
for (int i = 0; i < numMembers; i++)
{
offsetVec[i] = netOffset;
const Type* memberType = stype->getElementTypes()[i];
netOffset += this->findOptimalStorageSize(memberType);
}
return offsetVec;
}
//---------------------------------------------------------------------------