llvm/llvm/lib/Target/PowerPC/PPCLowerMASSVEntries.cpp

//===-- PPCLowerMASSVEntries.cpp ------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements lowering of MASSV (SIMD) entries for specific PowerPC
// subtargets.
// Following is an example of a conversion specific to Power9 subtarget:
// __sind2_massv ---> __sind2_P9
//
//===----------------------------------------------------------------------===//

#include "PPC.h"
#include "PPCSubtarget.h"
#include "PPCTargetMachine.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"

#define DEBUG_TYPE …

usingnamespacellvm;

namespace {

static StringRef MASSVFuncs[] = …;

class PPCLowerMASSVEntries : public ModulePass { … };

} // namespace

/// Checks if the specified function name represents an entry in the MASSV
/// library.
bool PPCLowerMASSVEntries::isMASSVFunc(StringRef Name) { … }

// FIXME:
/// Returns a string corresponding to the specified PowerPC subtarget. e.g.:
/// "_P8" for Power8, "_P9" for Power9. The string is used as a suffix while
/// generating subtarget-specific MASSV library functions. Current support
/// includes minimum subtarget Power8 for Linux and Power7 for AIX.
StringRef PPCLowerMASSVEntries::getCPUSuffix(const PPCSubtarget *Subtarget) { … }

/// Creates PowerPC subtarget-specific name corresponding to the specified
/// generic MASSV function, and the PowerPC subtarget.
std::string
PPCLowerMASSVEntries::createMASSVFuncName(Function &Func,
                                          const PPCSubtarget *Subtarget) { … }

/// If there are proper fast-math flags, this function creates llvm.pow
/// intrinsics when the exponent is 0.25 or 0.75.
bool PPCLowerMASSVEntries::handlePowSpecialCases(CallInst *CI, Function &Func,
                                                 Module &M) { … }

/// Lowers generic MASSV entries to PowerPC subtarget-specific MASSV entries.
/// e.g.: __sind2_massv --> __sind2_P9 for a Power9 subtarget.
/// Both function prototypes and their callsites are updated during lowering.
bool PPCLowerMASSVEntries::lowerMASSVCall(CallInst *CI, Function &Func,
                                          Module &M,
                                          const PPCSubtarget *Subtarget) { … }

bool PPCLowerMASSVEntries::runOnModule(Module &M) { … }

char PPCLowerMASSVEntries::ID = …;

char &llvm::PPCLowerMASSVEntriesID = …;

INITIALIZE_PASS(…)

ModulePass *llvm::createPPCLowerMASSVEntriesPass() { … }