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//===-- llvm/CodeGen/AsmPrinter.h - AsmPrinter Framework --------*- C++ -*-===//
//
// 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 class is intended to be used as a base class for target-specific
// asmwriters. This class primarily takes care of printing global constants,
// which are printed in a very similar way across all targets.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_ASMPRINTER_H
#define LLVM_CODEGEN_ASMPRINTER_H
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/Support/DataTypes.h"
namespace llvm {
class Constant;
class Mangler;
class AsmPrinter : public MachineFunctionPass {
/// CurrentSection - The current section we are emitting to. This is
/// controlled and used by the SwitchSection method.
std::string CurrentSection;
/// FunctionNumber - This provides a unique ID for each function emitted in
/// this translation unit. It is autoincremented by SetupMachineFunction,
/// and can be accessed with getFunctionNumber() and
/// IncrementFunctionNumber().
///
unsigned FunctionNumber;
protected:
/// Output stream on which we're printing assembly code.
///
std::ostream &O;
/// Target machine description.
///
TargetMachine &TM;
/// Name-mangler for global names.
///
Mangler *Mang;
/// Cache of mangled name for current function. This is recalculated at the
/// beginning of each call to runOnMachineFunction().
///
std::string CurrentFnName;
//===------------------------------------------------------------------===//
// Properties to be set by the derived class ctor, used to configure the
// asmwriter.
/// CommentString - This indicates the comment character used by the
/// assembler.
const char *CommentString; // Defaults to "#"
/// GlobalPrefix - If this is set to a non-empty string, it is prepended
/// onto all global symbols. This is often used for "_" or ".".
const char *GlobalPrefix; // Defaults to ""
/// PrivateGlobalPrefix - This prefix is used for globals like constant
/// pool entries that are completely private to the .o file and should not
/// have names in the .o file. This is often "." or "L".
const char *PrivateGlobalPrefix; // Defaults to "."
/// GlobalVarAddrPrefix/Suffix - If these are nonempty, these strings
/// will enclose any GlobalVariable (that isn't a function)
///
const char *GlobalVarAddrPrefix; // Defaults to ""
const char *GlobalVarAddrSuffix; // Defaults to ""
/// FunctionAddrPrefix/Suffix - If these are nonempty, these strings
/// will enclose any GlobalVariable that points to a function.
/// For example, this is used by the IA64 backend to materialize
/// function descriptors, by decorating the ".data8" object with the
/// @fptr( ) link-relocation operator.
///
const char *FunctionAddrPrefix; // Defaults to ""
const char *FunctionAddrSuffix; // Defaults to ""
//===--- Data Emission Directives -------------------------------------===//
/// ZeroDirective - this should be set to the directive used to get some
/// number of zero bytes emitted to the current section. Common cases are
/// "\t.zero\t" and "\t.space\t". If this is set to null, the
/// Data*bitsDirective's will be used to emit zero bytes.
const char *ZeroDirective; // Defaults to "\t.zero\t"
/// AsciiDirective - This directive allows emission of an ascii string with
/// the standard C escape characters embedded into it.
const char *AsciiDirective; // Defaults to "\t.ascii\t"
/// AscizDirective - If not null, this allows for special handling of
/// zero terminated strings on this target. This is commonly supported as
/// ".asciz". If a target doesn't support this, it can be set to null.
const char *AscizDirective; // Defaults to "\t.asciz\t"
/// DataDirectives - These directives are used to output some unit of
/// integer data to the current section. If a data directive is set to
/// null, smaller data directives will be used to emit the large sizes.
const char *Data8bitsDirective; // Defaults to "\t.byte\t"
const char *Data16bitsDirective; // Defaults to "\t.short\t"
const char *Data32bitsDirective; // Defaults to "\t.long\t"
const char *Data64bitsDirective; // Defaults to "\t.quad\t"
//===--- Alignment Information ----------------------------------------===//
/// AlignDirective - The directive used to emit round up to an alignment
/// boundary.
///
const char *AlignDirective; // Defaults to "\t.align\t"
/// AlignmentIsInBytes - If this is true (the default) then the asmprinter
/// emits ".align N" directives, where N is the number of bytes to align to.
/// Otherwise, it emits ".align log2(N)", e.g. 3 to align to an 8 byte
/// boundary.
bool AlignmentIsInBytes; // Defaults to true
//===--- Section Switching Directives ---------------------------------===//
/// SwitchToSectionDirective - This is the directive used when we want to
/// emit a global to an arbitrary section. The section name is emited after
/// this.
const char *SwitchToSectionDirective; // Defaults to "\t.section\t"
/// ConstantPoolSection - This is the section that we SwitchToSection right
/// before emitting the constant pool for a function.
const char *ConstantPoolSection; // Defaults to "\t.section .rodata\n"
AsmPrinter(std::ostream &o, TargetMachine &tm)
: FunctionNumber(0), O(o), TM(tm),
CommentString("#"),
GlobalPrefix(""),
PrivateGlobalPrefix("."),
GlobalVarAddrPrefix(""),
GlobalVarAddrSuffix(""),
FunctionAddrPrefix(""),
FunctionAddrSuffix(""),
ZeroDirective("\t.zero\t"),
AsciiDirective("\t.ascii\t"),
AscizDirective("\t.asciz\t"),
Data8bitsDirective("\t.byte\t"),
Data16bitsDirective("\t.short\t"),
Data32bitsDirective("\t.long\t"),
Data64bitsDirective("\t.quad\t"),
AlignDirective("\t.align\t"),
AlignmentIsInBytes(true),
SwitchToSectionDirective("\t.section\t"),
ConstantPoolSection("\t.section .rodata\n") {
}
/// SwitchSection - Switch to the specified section of the executable if we
/// are not already in it! If GV is non-null and if the global has an
/// explicitly requested section, we switch to the section indicated for the
/// global instead of NewSection.
///
/// If the new section is an empty string, this method forgets what the
/// current section is, but does not emit a .section directive.
///
void SwitchSection(const char *NewSection, const GlobalValue *GV);
/// getFunctionNumber - Return a unique ID for the current function.
///
unsigned getFunctionNumber() const { return FunctionNumber; }
/// IncrementFunctionNumber - Increase Function Number. AsmPrinters should
/// not normally call this, as the counter is automatically bumped by
/// SetupMachineFunction.
void IncrementFunctionNumber() { FunctionNumber++; }
/// doInitialization - Set up the AsmPrinter when we are working on a new
/// module. If your pass overrides this, it must make sure to explicitly
/// call this implementation.
bool doInitialization(Module &M);
/// doFinalization - Shut down the asmprinter. If you override this in your
/// pass, you must make sure to call it explicitly.
bool doFinalization(Module &M);
/// SetupMachineFunction - This should be called when a new MachineFunction
/// is being processed from runOnMachineFunction.
void SetupMachineFunction(MachineFunction &MF);
void EmitConstantPool(MachineConstantPool *MCP);
/// EmitAlignment - Emit an alignment directive to the specified power of
/// two boundary. For example, if you pass in 3 here, you will get an 8
/// byte alignment. If a global value is specified, and if that global has
/// an explicit alignment requested, it will override the alignment request.
void EmitAlignment(unsigned NumBits, const GlobalValue *GV = 0) const;
/// EmitZeros - Emit a block of zeros.
///
void EmitZeros(uint64_t NumZeros) const;
/// EmitConstantValueOnly - Print out the specified constant, without a
/// storage class. Only constants of first-class type are allowed here.
void EmitConstantValueOnly(const Constant *CV);
/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
///
void EmitGlobalConstant(const Constant* CV);
};
}
#endif
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