Files
clang-p2996/llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.h
Alex Bradbury b22f751fa7 Thread MCSubtargetInfo through Target::createMCAsmBackend
Currently it's not possible to access MCSubtargetInfo from a TgtMCAsmBackend. 
D20830 threaded an MCSubtargetInfo reference through 
MCAsmBackend::relaxInstruction, but this isn't the only function that would 
benefit from access. This patch removes the Triple and CPUString arguments 
from createMCAsmBackend and replaces them with MCSubtargetInfo.

This patch just changes the interface without making any intentional 
functional changes. Once in, several cleanups are possible:
* Get rid of the awkward MCSubtargetInfo handling in ARMAsmBackend
* Support 16-bit instructions when valid in MipsAsmBackend::writeNopData
* Get rid of the CPU string parsing in X86AsmBackend and just use a SubtargetFeature for HasNopl
* Emit 16-bit nops in RISCVAsmBackend::writeNopData if the compressed instruction set extension is enabled (see D41221)

This change initially exposed PR35686, which has since been resolved in r321026.

Differential Revision: https://reviews.llvm.org/D41349

llvm-svn: 321692
2018-01-03 08:53:05 +00:00

112 lines
3.7 KiB
C++

//===-- PPCMCTargetDesc.h - PowerPC Target Descriptions ---------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file provides PowerPC specific target descriptions.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TARGET_POWERPC_MCTARGETDESC_PPCMCTARGETDESC_H
#define LLVM_LIB_TARGET_POWERPC_MCTARGETDESC_PPCMCTARGETDESC_H
// GCC #defines PPC on Linux but we use it as our namespace name
#undef PPC
#include "llvm/Support/MathExtras.h"
#include <cstdint>
#include <memory>
namespace llvm {
class MCAsmBackend;
class MCCodeEmitter;
class MCContext;
class MCInstrInfo;
class MCObjectWriter;
class MCRegisterInfo;
class MCSubtargetInfo;
class MCTargetOptions;
class Target;
class Triple;
class StringRef;
class raw_pwrite_stream;
Target &getThePPC32Target();
Target &getThePPC64Target();
Target &getThePPC64LETarget();
MCCodeEmitter *createPPCMCCodeEmitter(const MCInstrInfo &MCII,
const MCRegisterInfo &MRI,
MCContext &Ctx);
MCAsmBackend *createPPCAsmBackend(const Target &T, const MCSubtargetInfo &STI,
const MCRegisterInfo &MRI,
const MCTargetOptions &Options);
/// Construct an PPC ELF object writer.
std::unique_ptr<MCObjectWriter> createPPCELFObjectWriter(raw_pwrite_stream &OS,
bool Is64Bit,
bool IsLittleEndian,
uint8_t OSABI);
/// Construct a PPC Mach-O object writer.
std::unique_ptr<MCObjectWriter> createPPCMachObjectWriter(raw_pwrite_stream &OS,
bool Is64Bit,
uint32_t CPUType,
uint32_t CPUSubtype);
/// Returns true iff Val consists of one contiguous run of 1s with any number of
/// 0s on either side. The 1s are allowed to wrap from LSB to MSB, so
/// 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is not,
/// since all 1s are not contiguous.
static inline bool isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME) {
if (!Val)
return false;
if (isShiftedMask_32(Val)) {
// look for the first non-zero bit
MB = countLeadingZeros(Val);
// look for the first zero bit after the run of ones
ME = countLeadingZeros((Val - 1) ^ Val);
return true;
} else {
Val = ~Val; // invert mask
if (isShiftedMask_32(Val)) {
// effectively look for the first zero bit
ME = countLeadingZeros(Val) - 1;
// effectively look for the first one bit after the run of zeros
MB = countLeadingZeros((Val - 1) ^ Val) + 1;
return true;
}
}
// no run present
return false;
}
} // end namespace llvm
// Generated files will use "namespace PPC". To avoid symbol clash,
// undefine PPC here. PPC may be predefined on some hosts.
#undef PPC
// Defines symbolic names for PowerPC registers. This defines a mapping from
// register name to register number.
//
#define GET_REGINFO_ENUM
#include "PPCGenRegisterInfo.inc"
// Defines symbolic names for the PowerPC instructions.
//
#define GET_INSTRINFO_ENUM
#define GET_INSTRINFO_SCHED_ENUM
#include "PPCGenInstrInfo.inc"
#define GET_SUBTARGETINFO_ENUM
#include "PPCGenSubtargetInfo.inc"
#endif // LLVM_LIB_TARGET_POWERPC_MCTARGETDESC_PPCMCTARGETDESC_H