llvm-6502/include/llvm/Target/SubtargetFeature.h
2005-10-23 05:25:19 +00:00

91 lines
3.2 KiB
C++

//===-- llvm/Target/SubtargetFeature.h - CPU characteristics ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Jim Laskey and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines and manages user or tool specified CPU characteristics.
// The intent is to be able to package specific features that should or should
// not be used on a specific target processor. A tool, such as llc, could, as
// as example, gather chip info from the command line, a long with features
// that should be used on that chip.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_SUBTARGETFEATURE_H
#define LLVM_TARGET_SUBTARGETFEATURE_H
#include <string>
#include <vector>
#include <iosfwd>
#include "llvm/Support/DataTypes.h"
namespace llvm {
//===----------------------------------------------------------------------===//
///
/// SubtargetFeatureKV - Used to provide key value pairs for feature and
/// CPU bit flags.
//
struct SubtargetFeatureKV {
const char *Key; // K-V key string
const char *Desc; // Help descriptor
uint32_t Value; // K-V integer value
// Compare routine for std binary search
bool operator<(const std::string &S) const {
return strcmp(Key, S.c_str()) < 0;
}
};
//===----------------------------------------------------------------------===//
///
/// SubtargetFeatures - Manages the enabling and disabling of subtarget
/// specific features. Features are encoded as a string of the form
/// "cpu,+attr1,+attr2,-attr3,...,+attrN"
/// A comma separates each feature from the next (all lowercase.)
/// The first feature is always the CPU subtype (eg. pentiumm). If the CPU
/// value is "generic" then the CPU subtype should be generic for the target.
/// Each of the remaining features is prefixed with + or - indicating whether
/// that feature should be enabled or disabled contrary to the cpu
/// specification.
///
class SubtargetFeatures {
std::vector<std::string> Features; // Subtarget features as a vector
public:
SubtargetFeatures(const std::string &Initial = std::string());
/// Features string accessors.
std::string getString() const;
void setString(const std::string &Initial);
/// Setting CPU string. Replaces previous setting. Setting to "" clears CPU.
///
void setCPU(const std::string &String);
/// Adding Features.
void AddFeature(const std::string &String, bool IsEnabled = true);
/// Parse feature string for quick usage.
static uint32_t Parse(const std::string &String,
const std::string &DefaultCPU,
const SubtargetFeatureKV *CPUTable,
size_t CPUTableSize,
const SubtargetFeatureKV *FeatureTable,
size_t FeatureTableSize);
/// Print feature string.
void print(std::ostream &OS) const;
// Dump feature info.
void dump() const;
};
} // End namespace llvm
#endif