llvm-mirror/lib/Target/AMDGPU/AMDGPULegalizerInfo.cpp

//===- AMDGPULegalizerInfo.cpp -----------------------------------*- C++ -*-==//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
/// \file
/// This file implements the targeting of the Machinelegalizer class for
/// AMDGPU.
/// \todo This should be generated by TableGen.
//===----------------------------------------------------------------------===//

#include "AMDGPU.h"
#include "AMDGPULegalizerInfo.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/Debug.h"

using namespace llvm;
using namespace LegalizeActions;

AMDGPULegalizerInfo::AMDGPULegalizerInfo(const SISubtarget &ST,
                                         const GCNTargetMachine &TM) {
  using namespace TargetOpcode;

  const LLT S1= LLT::scalar(1);
  const LLT V2S16 = LLT::vector(2, 16);
  const LLT S32 = LLT::scalar(32);
  const LLT S64 = LLT::scalar(64);
  const LLT P1 = LLT::pointer(AMDGPUAS::GLOBAL_ADDRESS, 64);
  const LLT P2 = LLT::pointer(AMDGPUAS::CONSTANT_ADDRESS, 64);

  setAction({G_ADD, S32}, Legal);
  setAction({G_MUL, S32}, Legal);
  setAction({G_AND, S32}, Legal);
  setAction({G_OR, S32}, Legal);
  setAction({G_XOR, S32}, Legal);

  setAction({G_BITCAST, V2S16}, Legal);
  setAction({G_BITCAST, 1, S32}, Legal);

  setAction({G_BITCAST, S32}, Legal);
  setAction({G_BITCAST, 1, V2S16}, Legal);

  // FIXME: i1 operands to intrinsics should always be legal, but other i1
  // values may not be legal.  We need to figure out how to distinguish
  // between these two scenarios.
  setAction({G_CONSTANT, S1}, Legal);
  setAction({G_CONSTANT, S32}, Legal);
  setAction({G_CONSTANT, S64}, Legal);

  setAction({G_FCONSTANT, S32}, Legal);
  setAction({G_FCONSTANT, S64}, Legal);

  setAction({G_IMPLICIT_DEF, S32}, Legal);
  setAction({G_IMPLICIT_DEF, S64}, Legal);

  setAction({G_FADD, S32}, Legal);

  setAction({G_FCMP, S1}, Legal);
  setAction({G_FCMP, 1, S32}, Legal);
  setAction({G_FCMP, 1, S64}, Legal);

  setAction({G_FMUL, S32}, Legal);

  setAction({G_ZEXT, S64}, Legal);
  setAction({G_ZEXT, 1, S32}, Legal);

  setAction({G_FPTOSI, S32}, Legal);
  setAction({G_FPTOSI, 1, S32}, Legal);

  setAction({G_FPTOUI, S32}, Legal);
  setAction({G_FPTOUI, 1, S32}, Legal);

  setAction({G_GEP, P1}, Legal);
  setAction({G_GEP, P2}, Legal);
  setAction({G_GEP, 1, S64}, Legal);

  setAction({G_ICMP, S1}, Legal);
  setAction({G_ICMP, 1, S32}, Legal);

  setAction({G_LOAD, P1}, Legal);
  setAction({G_LOAD, P2}, Legal);
  setAction({G_LOAD, S32}, Legal);
  setAction({G_LOAD, 1, P1}, Legal);
  setAction({G_LOAD, 1, P2}, Legal);

  setAction({G_SELECT, S32}, Legal);
  setAction({G_SELECT, 1, S1}, Legal);

  setAction({G_SHL, S32}, Legal);

  setAction({G_STORE, S32}, Legal);
  setAction({G_STORE, 1, P1}, Legal);

  // FIXME: When RegBankSelect inserts copies, it will only create new
  // registers with scalar types.  This means we can end up with
  // G_LOAD/G_STORE/G_GEP instruction with scalar types for their pointer
  // operands.  In assert builds, the instruction selector will assert
  // if it sees a generic instruction which isn't legal, so we need to
  // tell it that scalar types are legal for pointer operands
  setAction({G_GEP, S64}, Legal);
  setAction({G_LOAD, 1, S64}, Legal);
  setAction({G_STORE, 1, S64}, Legal);

  // FIXME: Doesn't handle extract of illegal sizes.
  getActionDefinitionsBuilder(G_EXTRACT)
    .unsupportedIf([=](const LegalityQuery &Query) {
        return Query.Types[0].getSizeInBits() >= Query.Types[1].getSizeInBits();
      })
    .legalIf([=](const LegalityQuery &Query) {
        const LLT &Ty0 = Query.Types[0];
        const LLT &Ty1 = Query.Types[1];
        return (Ty0.getSizeInBits() % 32 == 0) &&
               (Ty1.getSizeInBits() % 32 == 0);
      });

  // Merge/Unmerge
  for (unsigned Op : {G_MERGE_VALUES, G_UNMERGE_VALUES}) {
    unsigned BigTyIdx = Op == G_MERGE_VALUES ? 0 : 1;
    unsigned LitTyIdx = Op == G_MERGE_VALUES ? 1 : 0;

    getActionDefinitionsBuilder(Op)
      .legalIf([=](const LegalityQuery &Query) {
          const LLT &BigTy = Query.Types[BigTyIdx];
          const LLT &LitTy = Query.Types[LitTyIdx];
          return BigTy.getSizeInBits() % 32 == 0 &&
                 LitTy.getSizeInBits() % 32 == 0 &&
                 BigTy.getSizeInBits() <= 512;
        })
      // Any vectors left are the wrong size. Scalarize them.
      .fewerElementsIf([](const LegalityQuery &Query) { return true; },
                       [](const LegalityQuery &Query) {
                         return std::make_pair(
                           0, Query.Types[0].getElementType());
                       })
      .fewerElementsIf([](const LegalityQuery &Query) { return true; },
                       [](const LegalityQuery &Query) {
                         return std::make_pair(
                           1, Query.Types[1].getElementType());
                       });

  }

  computeTables();
}