llvm-6502/include/llvm/Target/TargetMachine.h
Evan Cheng 3ef1c8759a Teach if-converter to be more careful with predicating instructions that would
take multiple cycles to decode.
For the current if-converter clients (actually only ARM), the instructions that
are predicated on false are not nops. They would still take machine cycles to
decode. Micro-coded instructions such as LDM / STM can potentially take multiple
cycles to decode. If-converter should take treat them as non-micro-coded
simple instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113570 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-10 01:29:16 +00:00

375 lines
14 KiB
C++

//===-- llvm/Target/TargetMachine.h - Target Information --------*- 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 the TargetMachine and LLVMTargetMachine classes.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_TARGETMACHINE_H
#define LLVM_TARGET_TARGETMACHINE_H
#include "llvm/Target/TargetInstrItineraries.h"
#include <cassert>
#include <string>
namespace llvm {
class Target;
class MCAsmInfo;
class TargetData;
class TargetSubtarget;
class TargetInstrInfo;
class TargetIntrinsicInfo;
class TargetJITInfo;
class TargetLowering;
class TargetSelectionDAGInfo;
class TargetFrameInfo;
class JITCodeEmitter;
class MCContext;
class TargetRegisterInfo;
class PassManagerBase;
class PassManager;
class Pass;
class TargetELFWriterInfo;
class formatted_raw_ostream;
// Relocation model types.
namespace Reloc {
enum Model {
Default,
Static,
PIC_, // Cannot be named PIC due to collision with -DPIC
DynamicNoPIC
};
}
// Code model types.
namespace CodeModel {
enum Model {
Default,
Small,
Kernel,
Medium,
Large
};
}
// Code generation optimization level.
namespace CodeGenOpt {
enum Level {
None, // -O0
Less, // -O1
Default, // -O2, -Os
Aggressive // -O3
};
}
namespace Sched {
enum Preference {
None, // No preference
Latency, // Scheduling for shortest total latency.
RegPressure, // Scheduling for lowest register pressure.
Hybrid, // Scheduling for both latency and register pressure.
ILP // Scheduling for ILP in low register pressure mode.
};
}
//===----------------------------------------------------------------------===//
///
/// TargetMachine - Primary interface to the complete machine description for
/// the target machine. All target-specific information should be accessible
/// through this interface.
///
class TargetMachine {
TargetMachine(const TargetMachine &); // DO NOT IMPLEMENT
void operator=(const TargetMachine &); // DO NOT IMPLEMENT
protected: // Can only create subclasses.
TargetMachine(const Target &);
/// getSubtargetImpl - virtual method implemented by subclasses that returns
/// a reference to that target's TargetSubtarget-derived member variable.
virtual const TargetSubtarget *getSubtargetImpl() const { return 0; }
/// TheTarget - The Target that this machine was created for.
const Target &TheTarget;
/// AsmInfo - Contains target specific asm information.
///
const MCAsmInfo *AsmInfo;
unsigned MCRelaxAll : 1;
public:
virtual ~TargetMachine();
const Target &getTarget() const { return TheTarget; }
// Interfaces to the major aspects of target machine information:
// -- Instruction opcode and operand information
// -- Pipelines and scheduling information
// -- Stack frame information
// -- Selection DAG lowering information
//
virtual const TargetInstrInfo *getInstrInfo() const { return 0; }
virtual const TargetFrameInfo *getFrameInfo() const { return 0; }
virtual const TargetLowering *getTargetLowering() const { return 0; }
virtual const TargetSelectionDAGInfo *getSelectionDAGInfo() const{ return 0; }
virtual const TargetData *getTargetData() const { return 0; }
/// getMCAsmInfo - Return target specific asm information.
///
const MCAsmInfo *getMCAsmInfo() const { return AsmInfo; }
/// getSubtarget - This method returns a pointer to the specified type of
/// TargetSubtarget. In debug builds, it verifies that the object being
/// returned is of the correct type.
template<typename STC> const STC &getSubtarget() const {
return *static_cast<const STC*>(getSubtargetImpl());
}
/// getRegisterInfo - If register information is available, return it. If
/// not, return null. This is kept separate from RegInfo until RegInfo has
/// details of graph coloring register allocation removed from it.
///
virtual const TargetRegisterInfo *getRegisterInfo() const { return 0; }
/// getIntrinsicInfo - If intrinsic information is available, return it. If
/// not, return null.
///
virtual const TargetIntrinsicInfo *getIntrinsicInfo() const { return 0; }
/// getJITInfo - If this target supports a JIT, return information for it,
/// otherwise return null.
///
virtual TargetJITInfo *getJITInfo() { return 0; }
/// getInstrItineraryData - Returns instruction itinerary data for the target
/// or specific subtarget.
///
virtual const InstrItineraryData *getInstrItineraryData() const {
return 0;
}
/// getELFWriterInfo - If this target supports an ELF writer, return
/// information for it, otherwise return null.
///
virtual const TargetELFWriterInfo *getELFWriterInfo() const { return 0; }
/// hasMCRelaxAll - Check whether all machine code instructions should be
/// relaxed.
bool hasMCRelaxAll() const { return MCRelaxAll; }
/// setMCRelaxAll - Set whether all machine code instructions should be
/// relaxed.
void setMCRelaxAll(bool Value) { MCRelaxAll = Value; }
/// getRelocationModel - Returns the code generation relocation model. The
/// choices are static, PIC, and dynamic-no-pic, and target default.
static Reloc::Model getRelocationModel();
/// setRelocationModel - Sets the code generation relocation model.
///
static void setRelocationModel(Reloc::Model Model);
/// getCodeModel - Returns the code model. The choices are small, kernel,
/// medium, large, and target default.
static CodeModel::Model getCodeModel();
/// setCodeModel - Sets the code model.
///
static void setCodeModel(CodeModel::Model Model);
/// getAsmVerbosityDefault - Returns the default value of asm verbosity.
///
static bool getAsmVerbosityDefault();
/// setAsmVerbosityDefault - Set the default value of asm verbosity. Default
/// is false.
static void setAsmVerbosityDefault(bool);
/// getDataSections - Return true if data objects should be emitted into their
/// own section, corresponds to -fdata-sections.
static bool getDataSections();
/// getFunctionSections - Return true if functions should be emitted into
/// their own section, corresponding to -ffunction-sections.
static bool getFunctionSections();
/// setDataSections - Set if the data are emit into separate sections.
static void setDataSections(bool);
/// setFunctionSections - Set if the functions are emit into separate
/// sections.
static void setFunctionSections(bool);
/// CodeGenFileType - These enums are meant to be passed into
/// addPassesToEmitFile to indicate what type of file to emit, and returned by
/// it to indicate what type of file could actually be made.
enum CodeGenFileType {
CGFT_AssemblyFile,
CGFT_ObjectFile,
CGFT_Null // Do not emit any output.
};
/// getEnableTailMergeDefault - the default setting for -enable-tail-merge
/// on this target. User flag overrides.
virtual bool getEnableTailMergeDefault() const { return true; }
/// addPassesToEmitFile - Add passes to the specified pass manager to get the
/// specified file emitted. Typically this will involve several steps of code
/// generation. This method should return true if emission of this file type
/// is not supported, or false on success.
virtual bool addPassesToEmitFile(PassManagerBase &,
formatted_raw_ostream &,
CodeGenFileType,
CodeGenOpt::Level,
bool = true) {
return true;
}
/// addPassesToEmitMachineCode - Add passes to the specified pass manager to
/// get machine code emitted. This uses a JITCodeEmitter object to handle
/// actually outputting the machine code and resolving things like the address
/// of functions. This method returns true if machine code emission is
/// not supported.
///
virtual bool addPassesToEmitMachineCode(PassManagerBase &,
JITCodeEmitter &,
CodeGenOpt::Level,
bool = true) {
return true;
}
/// addPassesToEmitMC - Add passes to the specified pass manager to get
/// machine code emitted with the MCJIT. This method returns true if machine
/// code is not supported. It fills the MCContext Ctx pointer which can be
/// used to build custom MCStreamer.
///
virtual bool addPassesToEmitMC(PassManagerBase &,
MCContext *&,
CodeGenOpt::Level,
bool = true) {
return true;
}
};
/// LLVMTargetMachine - This class describes a target machine that is
/// implemented with the LLVM target-independent code generator.
///
class LLVMTargetMachine : public TargetMachine {
std::string TargetTriple;
protected: // Can only create subclasses.
LLVMTargetMachine(const Target &T, const std::string &TargetTriple);
private:
/// addCommonCodeGenPasses - Add standard LLVM codegen passes used for
/// both emitting to assembly files or machine code output.
///
bool addCommonCodeGenPasses(PassManagerBase &, CodeGenOpt::Level,
bool DisableVerify, MCContext *&OutCtx);
virtual void setCodeModelForJIT();
virtual void setCodeModelForStatic();
public:
/// addPassesToEmitFile - Add passes to the specified pass manager to get the
/// specified file emitted. Typically this will involve several steps of code
/// generation. If OptLevel is None, the code generator should emit code as
/// fast as possible, though the generated code may be less efficient.
virtual bool addPassesToEmitFile(PassManagerBase &PM,
formatted_raw_ostream &Out,
CodeGenFileType FileType,
CodeGenOpt::Level,
bool DisableVerify = true);
/// addPassesToEmitMachineCode - Add passes to the specified pass manager to
/// get machine code emitted. This uses a JITCodeEmitter object to handle
/// actually outputting the machine code and resolving things like the address
/// of functions. This method returns true if machine code emission is
/// not supported.
///
virtual bool addPassesToEmitMachineCode(PassManagerBase &PM,
JITCodeEmitter &MCE,
CodeGenOpt::Level,
bool DisableVerify = true);
/// addPassesToEmitMC - Add passes to the specified pass manager to get
/// machine code emitted with the MCJIT. This method returns true if machine
/// code is not supported. It fills the MCContext Ctx pointer which can be
/// used to build custom MCStreamer.
///
virtual bool addPassesToEmitMC(PassManagerBase &PM,
MCContext *&Ctx,
CodeGenOpt::Level OptLevel,
bool DisableVerify = true);
/// Target-Independent Code Generator Pass Configuration Options.
/// addPreISelPasses - This method should add any "last minute" LLVM->LLVM
/// passes (which are run just before instruction selector).
virtual bool addPreISel(PassManagerBase &, CodeGenOpt::Level) {
return true;
}
/// addInstSelector - This method should install an instruction selector pass,
/// which converts from LLVM code to machine instructions.
virtual bool addInstSelector(PassManagerBase &, CodeGenOpt::Level) {
return true;
}
/// addPreRegAlloc - This method may be implemented by targets that want to
/// run passes immediately before register allocation. This should return
/// true if -print-machineinstrs should print after these passes.
virtual bool addPreRegAlloc(PassManagerBase &, CodeGenOpt::Level) {
return false;
}
/// addPostRegAlloc - This method may be implemented by targets that want
/// to run passes after register allocation but before prolog-epilog
/// insertion. This should return true if -print-machineinstrs should print
/// after these passes.
virtual bool addPostRegAlloc(PassManagerBase &, CodeGenOpt::Level) {
return false;
}
/// addPreSched2 - This method may be implemented by targets that want to
/// run passes after prolog-epilog insertion and before the second instruction
/// scheduling pass. This should return true if -print-machineinstrs should
/// print after these passes.
virtual bool addPreSched2(PassManagerBase &, CodeGenOpt::Level) {
return false;
}
/// addPreEmitPass - This pass may be implemented by targets that want to run
/// passes immediately before machine code is emitted. This should return
/// true if -print-machineinstrs should print out the code after the passes.
virtual bool addPreEmitPass(PassManagerBase &, CodeGenOpt::Level) {
return false;
}
/// addCodeEmitter - This pass should be overridden by the target to add a
/// code emitter, if supported. If this is not supported, 'true' should be
/// returned.
virtual bool addCodeEmitter(PassManagerBase &, CodeGenOpt::Level,
JITCodeEmitter &) {
return true;
}
/// getEnableTailMergeDefault - the default setting for -enable-tail-merge
/// on this target. User flag overrides.
virtual bool getEnableTailMergeDefault() const { return true; }
};
} // End llvm namespace
#endif