llvm/lib/CodeGen/AsmPrinter.cpp
Duraid Madina 855a519741 add support for prefix/suffix strings to go around GlobalValue(s)
(which may or be function pointers) in the asmprinter. For the moment,
this changes nothing, except the IA64 backend which can use this to write:

  data8.ua  @fptr(blah__blah__mangled_function_name)

  (by setting FunctionAddrPrefix/Suffix to "@fptr(" / ")")


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21024 91177308-0d34-0410-b5e6-96231b3b80d8
2005-04-02 12:21:51 +00:00

315 lines
11 KiB
C++

//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the AsmPrinter class.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/Constants.h"
#include "llvm/Instruction.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
bool AsmPrinter::doInitialization(Module &M) {
Mang = new Mangler(M, GlobalPrefix);
return false;
}
bool AsmPrinter::doFinalization(Module &M) {
delete Mang; Mang = 0;
return false;
}
void AsmPrinter::setupMachineFunction(MachineFunction &MF) {
// What's my mangled name?
CurrentFnName = Mang->getValueName((Value*)MF.getFunction());
}
// emitAlignment - Emit an alignment directive to the specified power of two.
void AsmPrinter::emitAlignment(unsigned NumBits) const {
if (AlignmentIsInBytes) NumBits = 1 << NumBits;
O << AlignDirective << NumBits << "\n";
}
/// emitZeros - Emit a block of zeros.
///
void AsmPrinter::emitZeros(uint64_t NumZeros) const {
if (NumZeros) {
if (ZeroDirective)
O << ZeroDirective << NumZeros << "\n";
else {
for (; NumZeros; --NumZeros)
O << Data8bitsDirective << "0\n";
}
}
}
// Print out the specified constant, without a storage class. Only the
// constants valid in constant expressions can occur here.
void AsmPrinter::emitConstantValueOnly(const Constant *CV) {
if (CV->isNullValue() || isa<UndefValue>(CV))
O << "0";
else if (const ConstantBool *CB = dyn_cast<ConstantBool>(CV)) {
assert(CB == ConstantBool::True);
O << "1";
} else if (const ConstantSInt *CI = dyn_cast<ConstantSInt>(CV))
if (((CI->getValue() << 32) >> 32) == CI->getValue())
O << CI->getValue();
else
O << (unsigned long long)CI->getValue();
else if (const ConstantUInt *CI = dyn_cast<ConstantUInt>(CV))
O << CI->getValue();
else if (isa<GlobalValue>((Value*)CV)) {
// This is a constant address for a global variable or function. Use the
// name of the variable or function as the address value, possibly
// decorating it with GlobalVarAddrPrefix/Suffix or
// FunctionAddrPrefix/Suffix (these all default to "" )
if (isa<Function>((Value*)CV))
O << FunctionAddrPrefix << Mang->getValueName(CV) << FunctionAddrSuffix;
else
O << GlobalVarAddrPrefix << Mang->getValueName(CV) << GlobalVarAddrSuffix;
} else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
const TargetData &TD = TM.getTargetData();
switch(CE->getOpcode()) {
case Instruction::GetElementPtr: {
// generate a symbolic expression for the byte address
const Constant *ptrVal = CE->getOperand(0);
std::vector<Value*> idxVec(CE->op_begin()+1, CE->op_end());
if (int64_t Offset = TD.getIndexedOffset(ptrVal->getType(), idxVec)) {
if (Offset)
O << "(";
emitConstantValueOnly(ptrVal);
if (Offset > 0)
O << ") + " << Offset;
else if (Offset < 0)
O << ") - " << -Offset;
} else {
emitConstantValueOnly(ptrVal);
}
break;
}
case Instruction::Cast: {
// Support only non-converting or widening casts for now, that is, ones
// that do not involve a change in value. This assertion is really gross,
// and may not even be a complete check.
Constant *Op = CE->getOperand(0);
const Type *OpTy = Op->getType(), *Ty = CE->getType();
// Remember, kids, pointers can be losslessly converted back and forth
// into 32-bit or wider integers, regardless of signedness. :-P
assert(((isa<PointerType>(OpTy)
&& (Ty == Type::LongTy || Ty == Type::ULongTy
|| Ty == Type::IntTy || Ty == Type::UIntTy))
|| (isa<PointerType>(Ty)
&& (OpTy == Type::LongTy || OpTy == Type::ULongTy
|| OpTy == Type::IntTy || OpTy == Type::UIntTy))
|| (((TD.getTypeSize(Ty) >= TD.getTypeSize(OpTy))
&& OpTy->isLosslesslyConvertibleTo(Ty))))
&& "FIXME: Don't yet support this kind of constant cast expr");
O << "(";
emitConstantValueOnly(Op);
O << ")";
break;
}
case Instruction::Add:
O << "(";
emitConstantValueOnly(CE->getOperand(0));
O << ") + (";
emitConstantValueOnly(CE->getOperand(1));
O << ")";
break;
default:
assert(0 && "Unsupported operator!");
}
} else {
assert(0 && "Unknown constant value!");
}
}
/// toOctal - Convert the low order bits of X into an octal digit.
///
static inline char toOctal(int X) {
return (X&7)+'0';
}
/// getAsCString - Return the specified array as a C compatible string, only if
/// the predicate isString is true.
///
static void printAsCString(std::ostream &O, const ConstantArray *CVA) {
assert(CVA->isString() && "Array is not string compatible!");
O << "\"";
for (unsigned i = 0; i != CVA->getNumOperands(); ++i) {
unsigned char C =
(unsigned char)cast<ConstantInt>(CVA->getOperand(i))->getRawValue();
if (C == '"') {
O << "\\\"";
} else if (C == '\\') {
O << "\\\\";
} else if (isprint(C)) {
O << C;
} else {
switch(C) {
case '\b': O << "\\b"; break;
case '\f': O << "\\f"; break;
case '\n': O << "\\n"; break;
case '\r': O << "\\r"; break;
case '\t': O << "\\t"; break;
default:
O << '\\';
O << toOctal(C >> 6);
O << toOctal(C >> 3);
O << toOctal(C >> 0);
break;
}
}
}
O << "\"";
}
/// emitGlobalConstant - Print a general LLVM constant to the .s file.
///
void AsmPrinter::emitGlobalConstant(const Constant *CV) {
const TargetData &TD = TM.getTargetData();
if (CV->isNullValue() || isa<UndefValue>(CV)) {
emitZeros(TD.getTypeSize(CV->getType()));
return;
} else if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) {
if (CVA->isString()) {
O << AsciiDirective;
printAsCString(O, CVA);
O << "\n";
} else { // Not a string. Print the values in successive locations
for (unsigned i = 0, e = CVA->getNumOperands(); i != e; ++i)
emitGlobalConstant(CVA->getOperand(i));
}
return;
} else if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) {
// Print the fields in successive locations. Pad to align if needed!
const StructLayout *cvsLayout = TD.getStructLayout(CVS->getType());
uint64_t sizeSoFar = 0;
for (unsigned i = 0, e = CVS->getNumOperands(); i != e; ++i) {
const Constant* field = CVS->getOperand(i);
// Check if padding is needed and insert one or more 0s.
uint64_t fieldSize = TD.getTypeSize(field->getType());
uint64_t padSize = ((i == e-1? cvsLayout->StructSize
: cvsLayout->MemberOffsets[i+1])
- cvsLayout->MemberOffsets[i]) - fieldSize;
sizeSoFar += fieldSize + padSize;
// Now print the actual field value
emitGlobalConstant(field);
// Insert the field padding unless it's zero bytes...
emitZeros(padSize);
}
assert(sizeSoFar == cvsLayout->StructSize &&
"Layout of constant struct may be incorrect!");
return;
} else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) {
// FP Constants are printed as integer constants to avoid losing
// precision...
double Val = CFP->getValue();
if (CFP->getType() == Type::DoubleTy) {
union DU { // Abide by C TBAA rules
double FVal;
uint64_t UVal;
} U;
U.FVal = Val;
if (Data64bitsDirective)
O << Data64bitsDirective << U.UVal << "\t" << CommentString
<< " double value: " << Val << "\n";
else if (TD.isBigEndian()) {
O << Data32bitsDirective << unsigned(U.UVal >> 32)
<< "\t" << CommentString << " double most significant word "
<< Val << "\n";
O << Data32bitsDirective << unsigned(U.UVal)
<< "\t" << CommentString << " double least significant word "
<< Val << "\n";
} else {
O << Data32bitsDirective << unsigned(U.UVal)
<< "\t" << CommentString << " double least significant word " << Val
<< "\n";
O << Data32bitsDirective << unsigned(U.UVal >> 32)
<< "\t" << CommentString << " double most significant word " << Val
<< "\n";
}
return;
} else {
union FU { // Abide by C TBAA rules
float FVal;
int32_t UVal;
} U;
U.FVal = (float)Val;
O << Data32bitsDirective << U.UVal << "\t" << CommentString
<< " float " << Val << "\n";
return;
}
} else if (CV->getType() == Type::ULongTy || CV->getType() == Type::LongTy) {
if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
uint64_t Val = CI->getRawValue();
if (Data64bitsDirective)
O << Data64bitsDirective << Val << "\n";
else if (TD.isBigEndian()) {
O << Data32bitsDirective << unsigned(Val >> 32)
<< "\t" << CommentString << " Double-word most significant word "
<< Val << "\n";
O << Data32bitsDirective << unsigned(Val)
<< "\t" << CommentString << " Double-word least significant word "
<< Val << "\n";
} else {
O << Data32bitsDirective << unsigned(Val)
<< "\t" << CommentString << " Double-word least significant word "
<< Val << "\n";
O << Data32bitsDirective << unsigned(Val >> 32)
<< "\t" << CommentString << " Double-word most significant word "
<< Val << "\n";
}
return;
}
}
const Type *type = CV->getType();
switch (type->getTypeID()) {
case Type::BoolTyID:
case Type::UByteTyID: case Type::SByteTyID:
O << Data8bitsDirective;
break;
case Type::UShortTyID: case Type::ShortTyID:
O << Data16bitsDirective;
break;
case Type::PointerTyID:
if (TD.getPointerSize() == 8) {
O << Data64bitsDirective;
break;
}
//Fall through for pointer size == int size
case Type::UIntTyID: case Type::IntTyID:
O << Data32bitsDirective;
break;
case Type::ULongTyID: case Type::LongTyID:
assert (0 && "Should have already output double-word constant.");
case Type::FloatTyID: case Type::DoubleTyID:
assert (0 && "Should have already output floating point constant.");
default:
assert (0 && "Can't handle printing this type of thing");
break;
}
emitConstantValueOnly(CV);
O << "\n";
}