XeVMToLLVM.cpp

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//===-- XeVMToLLVM.cpp - XeVM to LLVM dialect conversion --------*- C++ -*-===//
//
// This file is licensed 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
//
//===----------------------------------------------------------------------===//
 
#include "mlir/Conversion/XeVMToLLVM/XeVMToLLVM.h"
 
#include "mlir/Conversion/LLVMCommon/Pattern.h"
#include "mlir/Dialect/GPU/IR/GPUDialect.h"
#include "mlir/Dialect/LLVMIR/FunctionCallUtils.h"
#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
#include "mlir/Dialect/LLVMIR/XeVMDialect.h"
#include "mlir/Pass/Pass.h"
#include "mlir/Support/LLVM.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/MathExtras.h"
 
#include "mlir/IR/BuiltinTypes.h"
#include "mlir/IR/Matchers.h"
#include "mlir/IR/Types.h"
#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
 
#include "llvm/ADT/TypeSwitch.h"
 
namespace mlir {
#define GEN_PASS_DEF_CONVERTXEVMTOLLVMPASS
#include "mlir/Conversion/Passes.h.inc"
} // namespace mlir
 
using namespace mlir;
using namespace xevm;
 
namespace {
 
struct LLVMFuncAttributeOptions {
  bool isConvergent = false;
  bool isNoUnwind = false;
  bool isWillReturn = false;
  LLVM::MemoryEffectsAttr memEffectsAttr{};
};
static constexpr LLVMFuncAttributeOptions noUnwindAttrs = {
    false, true, false, {}};
static constexpr LLVMFuncAttributeOptions noUnwindWillReturnAttrs = {
    false, true, true, {}};
static constexpr LLVMFuncAttributeOptions convergentNoUnwindWillReturnAttrs = {
    true, true, true, {}};
 
std::string getTypeMangling(Type ty, bool isUnsigned = false) {
  return TypeSwitch<Type, std::string>(ty)
      .Case([isUnsigned](VectorType ty) -> std::string {
        return "Dv" + std::to_string(ty.getNumElements()) + "_" +
               getTypeMangling(ty.getElementType(), isUnsigned);
      })
      .Case([](Float16Type) -> std::string { return "Dh"; })
      .Case([](Float32Type) -> std::string { return "f"; })
      .Case([](Float64Type) -> std::string { return "d"; })
      .Case([isUnsigned](IntegerType ty) -> std::string {
        switch (ty.getWidth()) {
        case 8:
          return isUnsigned ? "h" : "c";
        case 16:
          return isUnsigned ? "t" : "s";
        case 32:
          return isUnsigned ? "j" : "i";
        case 64:
          return isUnsigned ? "m" : "l";
        default:
          llvm_unreachable("unhandled integer type");
        }
      })
      .DefaultUnreachable("unhandled type for mangling");
}
 
std::string mangle(StringRef baseName, ArrayRef<Type> types,
                   ArrayRef<bool> isUnsigned = {}) {
  assert((isUnsigned.empty() || isUnsigned.size() == types.size()) &&
         "Signedness info doesn't match");
  std::string s;
  llvm::raw_string_ostream os(s);
  llvm::SmallDenseMap<Type, unsigned> substitutions;
  os << "_Z" << baseName.size() << baseName;
  for (auto [idx, type] : llvm::enumerate(types)) {
    auto it = substitutions.find(type);
    if (it != substitutions.end()) {
      os << "S";
      // First substitution is `S_`, second is `S0_`, and so on.
      if (unsigned firstIdx = it->getSecond(); firstIdx > 0)
        os << firstIdx - 1;
      os << "_";
    } else {
      if (!type.isIntOrFloat())
        substitutions[type] = substitutions.size();
      os << getTypeMangling(type, isUnsigned.empty() ? false : isUnsigned[idx]);
    }
  }
  return os.str();
}
 
// Returns the mangling of `ty` used to name an overloaded `llvm.genx.GenISA.*`
// intrinsic: `i32`, `v8i16`, ... Note that this is IGC's own scheme for its
// intrinsics, not the Itanium mangling used for the SPIR-V friendly and OCL
// builtins that `mangle` above produces.
std::string getGenISATypeMangling(Type ty) {
  return TypeSwitch<Type, std::string>(ty)
      .Case([](VectorType ty) -> std::string {
        return "v" + std::to_string(ty.getNumElements()) +
               getGenISATypeMangling(ty.getElementType());
      })
      .Case([](IntegerType ty) -> std::string {
        return "i" + std::to_string(ty.getWidth());
      })
      .DefaultUnreachable("unhandled type for GenISA mangling");
}
 
std::string builtinElemType(ElemType elemType) {
  switch (elemType) {
  case ElemType::BF8:
    return "bf8";
  case ElemType::F8:
    return "hf8";
  case ElemType::BF16:
    return "bf";
  case ElemType::F16:
    return "hf";
  case ElemType::F32:
    return "f";
  default:
    return stringifyElemType(elemType).str();
  }
}
 
static int32_t getL1CacheControl(LoadCacheControl cc) {
  int32_t control = 0;
  switch (cc) {
  case LoadCacheControl::USE_DEFAULT:
    control = -1;
    break;
  case LoadCacheControl::L1C_L2UC_L3UC:
  case LoadCacheControl::L1C_L2UC_L3C:
  case LoadCacheControl::L1C_L2C_L3UC:
  case LoadCacheControl::L1C_L2C_L3C:
    control = 1;
    break;
  case LoadCacheControl::L1S_L2UC_L3UC:
  case LoadCacheControl::L1S_L2UC_L3C:
  case LoadCacheControl::L1S_L2C_L3UC:
  case LoadCacheControl::L1S_L2C_L3C:
    control = 2;
    break;
  case LoadCacheControl::INVALIDATE_READ:
    control = 3;
    break;
  default:
    break;
  }
  return control;
}
 
static int32_t getL1CacheControl(StoreCacheControl cc) {
  int32_t control = 0;
  switch (cc) {
  case StoreCacheControl::USE_DEFAULT:
    control = -1;
    break;
  case StoreCacheControl::L1WT_L2UC_L3UC:
  case StoreCacheControl::L1WT_L2UC_L3WB:
  case StoreCacheControl::L1WT_L2WB_L3UC:
  case StoreCacheControl::L1WT_L2WB_L3WB:
    control = 1;
    break;
  case StoreCacheControl::L1WB_L2UC_L3UC:
  case StoreCacheControl::L1WB_L2WB_L3UC:
  case StoreCacheControl::L1WB_L2UC_L3WB:
    control = 2;
    break;
  case StoreCacheControl::L1S_L2UC_L3UC:
  case StoreCacheControl::L1S_L2UC_L3WB:
  case StoreCacheControl::L1S_L2WB_L3UC:
  case StoreCacheControl::L1S_L2WB_L3WB:
    control = 3;
    break;
  default:
    break;
  }
  return control;
}
 
static int32_t getL3CacheControl(LoadCacheControl cc) {
  int32_t control = 0;
  switch (cc) {
  case LoadCacheControl::USE_DEFAULT:
    control = -1;
    break;
  case LoadCacheControl::L1UC_L2UC_L3C:
  case LoadCacheControl::L1UC_L2C_L3C:
  case LoadCacheControl::L1C_L2UC_L3C:
  case LoadCacheControl::L1C_L2C_L3C:
  case LoadCacheControl::L1S_L2UC_L3C:
  case LoadCacheControl::L1S_L2C_L3C:
    control = 1;
    break;
  case LoadCacheControl::INVALIDATE_READ:
    control = 3;
    break;
  default:
    break;
  }
  return control;
}
 
static int32_t getL3CacheControl(StoreCacheControl cc) {
  int32_t control = 0;
  switch (cc) {
  case StoreCacheControl::USE_DEFAULT:
    control = -1;
    break;
  case StoreCacheControl::L1UC_L2UC_L3WB:
  case StoreCacheControl::L1UC_L2WB_L3WB:
  case StoreCacheControl::L1WT_L2UC_L3WB:
  case StoreCacheControl::L1WT_L2WB_L3WB:
  case StoreCacheControl::L1S_L2UC_L3WB:
  case StoreCacheControl::L1S_L2WB_L3WB:
  case StoreCacheControl::L1WB_L2UC_L3WB:
    control = 2;
    break;
  default:
    break;
  }
  return control;
}
 
static std::optional<LoadCacheControl> getCacheControl(PrefetchOp op) {
  return op.getCacheControl();
}
 
static std::optional<LoadCacheControl> getCacheControl(BlockLoad2dOp op) {
  return op.getCacheControl();
}
 
static std::optional<LoadCacheControl> getCacheControl(BlockLoadOp op) {
  return op.getCacheControl();
}
 
static std::optional<LoadCacheControl> getCacheControl(BlockPrefetch2dOp op) {
  return op.getCacheControl();
}
 
static std::optional<StoreCacheControl> getCacheControl(BlockStore2dOp op) {
  return op.getCacheControl();
}
 
static std::optional<StoreCacheControl> getCacheControl(BlockStoreOp op) {
  return op.getCacheControl();
}
 
static std::optional<LoadCacheControl> getCacheControl(LLVM::LoadOp op) {
  if (op->hasDiscardableAttr("cache_control")) {
    auto attr = op->getDiscardableAttrOfType<xevm::LoadCacheControlAttr>(
        "cache_control");
    if (!attr)
      return std::nullopt;
    return std::optional<LoadCacheControl>(attr.getValue());
  }
  return std::nullopt;
}
 
static std::optional<StoreCacheControl> getCacheControl(LLVM::StoreOp op) {
  if (op->hasDiscardableAttr("cache_control")) {
    auto attr = op->getDiscardableAttrOfType<xevm::StoreCacheControlAttr>(
        "cache_control");
    if (!attr)
      return std::nullopt;
    return std::optional<StoreCacheControl>(attr.getValue());
  }
  return std::nullopt;
}
 
template <typename OpType>
int32_t getL1CacheControl(OpType op) {
  return getL1CacheControl(*getCacheControl(op));
}
 
template <typename OpType>
int32_t getL3CacheControl(OpType op) {
  return getL3CacheControl(*getCacheControl(op));
}
 
template <typename OpType>
static std::optional<ArrayAttr>
getCacheControlMetadata(ConversionPatternRewriter &rewriter, OpType op) {
  if (!getCacheControl(op))
    return {};
 
  constexpr int32_t decorationCacheControlArity{3};
  constexpr int32_t loadCacheControlKey{6442};
  constexpr int32_t storeCacheControlKey{6443};
  constexpr bool isLoad = std::is_same_v<OpType, BlockLoad2dOp> ||
                          std::is_same_v<OpType, BlockPrefetch2dOp> ||
                          std::is_same_v<OpType, LLVM::LoadOp> ||
                          std::is_same_v<OpType, BlockLoadOp> ||
                          std::is_same_v<OpType, PrefetchOp>;
 
  // If the cache control is USE_DEFAULT, then we don’t emit any metadata.
  // Assert that if one of the L1 or L3 cache control values is USE_DEFAULT
  // (represented as -1), then both must be USE_DEFAULT; otherwise there is a
  // bug.
  assert(((getL1CacheControl<OpType>(op) == -1) ==
          (getL3CacheControl<OpType>(op) == -1)) &&
         "If one of L1 or L3 cache control is USE_DEFAULT, both must be "
         "USE_DEFAULT");
 
  if (getL1CacheControl<OpType>(op) == -1 &&
      getL3CacheControl<OpType>(op) == -1)
    return {};
  const int32_t controlKey{isLoad ? loadCacheControlKey : storeCacheControlKey};
  SmallVector<int32_t, decorationCacheControlArity> decorationsL1{
      controlKey, 0, getL1CacheControl<OpType>(op)};
  SmallVector<int32_t, decorationCacheControlArity> decorationsL3{
      controlKey, 1, getL3CacheControl<OpType>(op)};
  auto arrayAttrL1 = rewriter.getI32ArrayAttr(decorationsL1);
  auto arrayAttrL3 = rewriter.getI32ArrayAttr(decorationsL3);
 
  SmallVector<Attribute, 2> combinedAttrs = {arrayAttrL1, arrayAttrL3};
  return rewriter.getArrayAttr(combinedAttrs);
}
 
//===----------------------------------------------------------------------===//
// Cache control annotation utilities
//
// Instead of attaching cache control as MLIR attributes and handling them
// during LLVM translation, we directly emit llvm.intr.ptr.annotation op in
// MLIR.
//===----------------------------------------------------------------------===//
 
/// Build one cache-control payload string per attribute.
///
/// Each Attribute is expected to be an ArrayAttr of 3 IntegerAttr values:
///   [SPIR-V decoration token, cache level, cache control value]
///
/// A single entry produces a string like:  {6442:"0,1"}
/// where the quote characters (0x22) will appear as \22 in LLVM IR textual
/// form.
static SmallVector<std::string>
buildCacheControlPayloads(ArrayRef<Attribute> attrs) {
  SmallVector<std::string> payloads;
  llvm::StringMap<bool> seen;
 
  for (Attribute a : attrs) {
    auto arr = dyn_cast<ArrayAttr>(a);
    if (!arr)
      continue;
 
    auto vals = arr.getValue();
    assert(vals.size() == 3 &&
           "Expected exactly 3 integer values (Token, CacheLevel, "
           "ControlValue) in cache control attribute.");
 
    auto tokenAttr = dyn_cast<IntegerAttr>(vals[0]);
    auto secondAttr = dyn_cast<IntegerAttr>(vals[1]);
    auto thirdAttr = dyn_cast<IntegerAttr>(vals[2]);
 
    if (!tokenAttr || !secondAttr || !thirdAttr)
      continue;
 
    // Produce: {SPIR-V decoration token:"L1 cache control,L3 cache control"}
    // The quote char (0x22) is embedded literally; LLVM IR prints it as \22.
    std::string entry =
        llvm::formatv("{{{0}:\"{1},{2}\"}", tokenAttr.getValue().getZExtValue(),
                      secondAttr.getValue().getZExtValue(),
                      thirdAttr.getValue().getZExtValue());
 
    // Deduplicate identical annotations.
    if (!seen.insert({entry, true}).second)
      continue;
 
    payloads.push_back(std::move(entry));
  }
  return payloads;
}
/// Counter for generating unique global variable names.
static std::atomic<uint64_t> globalNameCounter{0};
 
/// Get or create a global metadata string and return a !llvm.ptr<1> value
/// pointing to it. The AddressOfOp is created at the current rewriter
/// insertion point; the GlobalOp is created at the module start.
static Value createMetadataStringPtr(ConversionPatternRewriter &rewriter,
                                     Operation *moduleOp, Location loc,
                                     StringRef value, StringRef nameHint) {
  // Build null-terminated string.
  std::string strWithNull = value.str();
  strWithNull.push_back('\0');
  StringRef strRef(strWithNull.data(), strWithNull.size());
 
  auto as1PtrTy = LLVM::LLVMPointerType::get(rewriter.getContext(), 1);
 
  // Search for an existing global with the same content.
  for (auto &op : moduleOp->getRegion(0).front()) {
    if (auto existingGlobal = dyn_cast<LLVM::GlobalOp>(&op)) {
      if (!existingGlobal.getSection() ||
          *existingGlobal.getSection() != "llvm.metadata")
        continue;
      if (auto strAttr =
              dyn_cast_or_null<StringAttr>(existingGlobal.getValueOrNull())) {
        if (strAttr.getValue() == strRef) {
          return LLVM::AddressOfOp::create(rewriter, loc, as1PtrTy,
                                           existingGlobal.getSymName());
        }
      }
    }
  }
 
  // Create new global at module start.
  auto i8Type = rewriter.getI8Type();
  auto arrayType = LLVM::LLVMArrayType::get(i8Type, strWithNull.size());
  std::string globalName =
      llvm::formatv("{0}.{1}", nameHint,
                    globalNameCounter.fetch_add(1, std::memory_order_relaxed))
          .str();
 
  {
    OpBuilder::InsertionGuard guard(rewriter);
    rewriter.setInsertionPointToStart(&moduleOp->getRegion(0).front());
 
    auto globalOp =
        LLVM::GlobalOp::create(rewriter, loc, arrayType,
                               /*isConstant=*/true, LLVM::Linkage::Private,
                               globalName, rewriter.getStringAttr(strRef));
    globalOp.setSection(StringRef("llvm.metadata"));
    globalOp.setUnnamedAddr(LLVM::UnnamedAddr::Global);
    globalOp.setAlignment(1);
    globalOp.setAddrSpace(1);
  }
  // InsertionGuard restores the original insertion point here.
 
  return LLVM::AddressOfOp::create(rewriter, loc, as1PtrTy, globalName);
}
 
/// Annotate a pointer value with cache control metadata by emitting chained
/// `llvm.intr.ptr.annotation` ops (LLVM::PtrAnnotation).
///
/// This is the MLIR-level equivalent of handleDecorationCacheControl() from
/// the LLVM translation layer. For each cache control attribute, it emits:
///
///   %ann = llvm.intr.ptr.annotation %ptr, @".str.cachecontrol.N",
///              @".str.file.N", 0, null : !llvm.ptr<AS>
///
/// Multiple annotations are chained: the result of each annotation op is
/// fed as the pointer input to the next one.
///
/// \param rewriter       The pattern rewriter.
/// \param loc            Source location for created ops.
/// \param ptr            The pointer value to annotate.
/// \param cacheControls  The cache control ArrayAttr (from
/// getCacheControlMetadata).
/// \param moduleOp       The enclosing module (for creating globals).
/// \returns The annotated pointer value (or the original ptr if no
/// annotations).
static Value annotatePtrWithCacheControl(ConversionPatternRewriter &rewriter,
                                         Location loc, Value ptr,
                                         ArrayAttr cacheControls,
                                         Operation *moduleOp) {
  SmallVector<std::string> payloads =
      buildCacheControlPayloads(cacheControls.getValue());
  if (payloads.empty())
    return ptr;
 
  auto ptrType = cast<LLVM::LLVMPointerType>(ptr.getType());
  auto as1PtrTy = LLVM::LLVMPointerType::get(rewriter.getContext(), 1);
  auto i32Ty = rewriter.getI32Type();
 
  // Create shared constants for all annotations on this pointer.
  Value fileStr =
      createMetadataStringPtr(rewriter, moduleOp, loc, "", ".str.file");
  Value lineVal = LLVM::ConstantOp::create(rewriter, loc, i32Ty, 0);
  Value nullAS1 = LLVM::ZeroOp::create(rewriter, loc, as1PtrTy);
 
  // Chain: each annotation takes the result of the previous one as its
  // pointer operand.
  Value curPtr = ptr;
  for (const std::string &payload : payloads) {
    Value annStr = createMetadataStringPtr(rewriter, moduleOp, loc, payload,
                                           ".str.cachecontrol");
    auto annOp = LLVM::PtrAnnotation::create(rewriter, loc, ptrType, curPtr,
                                             annStr, fileStr, lineVal, nullAS1);
    curPtr = annOp.getResult();
  }
 
  return curPtr;
}
 
/// Helper to apply cache control annotation on a pointer operand of a call.
/// Replaces the pointer argument of the call with an annotated version.
///
/// For operations that produce a call (like block load/store/prefetch), the
/// pointer is typically the first argument. This function:
/// 1. Builds the annotation chain on the pointer.
/// 2. Replaces the pointer operand in the provided args list.
///
/// \param rewriter     The pattern rewriter.
/// \param loc          Source location.
/// \param ptr          The original pointer value (first arg to the call).
/// \param cacheControls  The cache control metadata.
/// \param moduleOp     The enclosing module.
/// \param args         The argument list (modified in place: args[ptrIdx] is
/// replaced).
/// \param ptrIdx       Index of the pointer in the args list (default 0).
template <typename OpType>
static void
applyCacheControlAnnotation(ConversionPatternRewriter &rewriter, Location loc,
                            OpType op, SmallVectorImpl<Value> &args,
                            Operation *moduleOp, unsigned ptrIdx = 0) {
  std::optional<ArrayAttr> optCacheControls =
      getCacheControlMetadata(rewriter, op);
  if (!optCacheControls)
    return;
 
  Value annotatedPtr = annotatePtrWithCacheControl(rewriter, loc, args[ptrIdx],
                                                   *optCacheControls, moduleOp);
  args[ptrIdx] = annotatedPtr;
}
 
//===----------------------------------------------------------------------===//
// End cache control annotation utilities
//===----------------------------------------------------------------------===//
 
static LLVM::CallOp createDeviceFunctionCall(
    ConversionPatternRewriter &rewriter, StringRef funcName, Type retType,
    ArrayRef<Type> argTypes, ArrayRef<Value> args,
    mlir::ArrayRef<std::pair<unsigned, mlir::StringRef>> paramAttrs,
    LLVMFuncAttributeOptions funcAttributeOptions, Operation *op) {
  auto *moduleOp = op->getParentWithTrait<OpTrait::SymbolTable>();
  assert(moduleOp && "Expecting module");
  Location loc = op->getLoc();
 
  auto funcOpRes =
      LLVM::lookupOrCreateFn(rewriter, moduleOp, funcName, argTypes, retType);
  assert(!failed(funcOpRes));
  LLVM::LLVMFuncOp funcOp = funcOpRes.value();
  funcOp.setCConv(LLVM::cconv::CConv::SPIR_FUNC);
  funcOp.setConvergent(funcAttributeOptions.isConvergent);
  funcOp.setNoUnwind(funcAttributeOptions.isNoUnwind);
  funcOp.setWillReturn(funcAttributeOptions.isWillReturn);
 
  if (funcAttributeOptions.memEffectsAttr)
    funcOp.setMemoryEffectsAttr(funcAttributeOptions.memEffectsAttr);
 
  for (auto [idx, attrName] : paramAttrs)
    funcOp.setArgAttr(idx, attrName, rewriter.getUnitAttr());
 
  auto callOp = LLVM::CallOp::create(rewriter, loc, funcOp, args);
  SmallVector<NamedAttribute> discardableAttrs;
  auto copyAttr = [&](StringAttr name, Attribute attr) {
    if (callOp->getInherentAttr(name).has_value())
      callOp->setInherentAttr(name, attr);
    else
      discardableAttrs.emplace_back(name, attr);
  };
  for (NamedAttribute attr : funcOp->getDiscardableAttrDictionary())
    copyAttr(attr.getName(), attr.getValue());
  funcOp->getName().walkInherentAttrs(
      funcOp, [&](StringRef name, Attribute &attr) {
        copyAttr(rewriter.getStringAttr(name), attr);
      });
  callOp->setDiscardableAttrs(discardableAttrs);
 
  return callOp;
}
 
static unsigned getNumOperandsPerDword(xevm::ElemType pTy) {
  switch (pTy) {
  case xevm::ElemType::F32:
  case xevm::ElemType::TF32:
    return 1;
  case xevm::ElemType::BF16:
  case xevm::ElemType::F16:
    return 2;
  case xevm::ElemType::U8:
  case xevm::ElemType::S8:
  case xevm::ElemType::BF8:
  case xevm::ElemType::F8:
    return 4;
  case xevm::ElemType::E2M1:
  case xevm::ElemType::U4:
  case xevm::ElemType::S4:
    return 8;
  default:
    llvm_unreachable("unsupported xevm::ElemType");
  }
}
 
class MMAToOCLPattern : public OpConversionPattern<xevm::MMAOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(xevm::MMAOp op, xevm::MMAOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    if (!op.getC()) {
      return rewriter.notifyMatchFailure(op, "OCL requires C operand");
    }
    auto precisionA = op.getTypes().getA();
    auto precisionB = op.getTypes().getB();
    auto precisionC = op.getTypes().getC();
    auto precisionD = op.getTypes().getD();
    if (precisionC != precisionD) {
      return rewriter.notifyMatchFailure(op, "type of C and D need to match");
    }
    if (precisionC != xevm::ElemType::S32 &&
        precisionC != xevm::ElemType::F32 &&
        precisionC != xevm::ElemType::F16 &&
        precisionC != xevm::ElemType::BF16) {
      return rewriter.notifyMatchFailure(
          op, "type of C and D must be S32, F32, F16 or BF16");
    }
    if (precisionA == xevm::ElemType::S32 ||
        precisionA == xevm::ElemType::F32) {
      return rewriter.notifyMatchFailure(op, "type of A cannot be S32 or F32");
    }
    if (precisionB == xevm::ElemType::S32 ||
        precisionB == xevm::ElemType::F32) {
      return rewriter.notifyMatchFailure(op, "type of B cannot be S32 or F32");
    }
    constexpr uint32_t bitWidthPackedA{16};
    constexpr uint32_t bitWidthPackedB{32};
    auto loc = op.getLoc();
 
    auto castIfNeeded = [&](Value val, Type packedType) -> Value {
      VectorType origTy = cast<VectorType>(val.getType());
      const uint32_t vecBitSize =
          origTy.getNumElements() *
          origTy.getElementType().getIntOrFloatBitWidth();
      VectorType newTy = VectorType::get(
          vecBitSize / packedType.getIntOrFloatBitWidth(), packedType);
      if (origTy != newTy)
        val = LLVM::BitcastOp::create(rewriter, loc, newTy, val);
      return val;
    };
 
    Value a = op.getA();
    Type packedAType = (op.getTypes().getA() == xevm::ElemType::TF32)
                           ? cast<Type>(rewriter.getF32Type())
                           : rewriter.getIntegerType(bitWidthPackedA);
    a = castIfNeeded(a, packedAType);
 
    Value b = op.getB();
    Type packedBType = (op.getTypes().getB() == xevm::ElemType::TF32)
                           ? cast<Type>(rewriter.getF32Type())
                           : rewriter.getIntegerType(bitWidthPackedB);
    b = castIfNeeded(b, packedBType);
 
    Value c = op.getC();
    VectorType cOrigTy = cast<VectorType>(c.getType());
    VectorType resOrigTy = cast<VectorType>(op->getResultTypes()[0]);
    assert(cOrigTy == resOrigTy && "Accumulator and result type mismatch");
    // OCL builtins encode bfloat16 as int16
    VectorType cTy =
        cOrigTy.getElementType().isBF16()
            ? VectorType::get(cOrigTy.getShape(), rewriter.getIntegerType(16))
            : cOrigTy;
    VectorType resTy = cTy;
    if (cOrigTy != cTy)
      c = LLVM::BitcastOp::create(rewriter, loc, cTy, c);
 
    constexpr int32_t systolicDepth{8};
    std::string fnName =
        llvm::formatv("intel_sub_group_{0}_{1}_matrix_mad_k{2}",
                      stringifyElemType(op.getTypes().getA()).str(),
                      stringifyElemType(op.getTypes().getB()).str(),
                      systolicDepth *
                          getNumOperandsPerDword(op.getTypes().getA()))
            .str();
    SmallVector<Type> argTypes{a.getType(), b.getType(), cTy};
    fnName = mangle(fnName, argTypes);
    SmallVector<Value> args{a, b, c};
 
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/LLVM::ModRefInfo::NoModRef,
        /*argMem=*/LLVM::ModRefInfo::NoModRef,
        /*inaccessibleMem=*/LLVM::ModRefInfo::NoModRef,
        /*errnoMem=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem0=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem1=*/LLVM::ModRefInfo::NoModRef);
    auto funcAttrs = convergentNoUnwindWillReturnAttrs;
    funcAttrs.memEffectsAttr = memAttr;
    Value result =
        createDeviceFunctionCall(rewriter, fnName, resTy, argTypes, args, {},
                                 funcAttrs, op.getOperation())
            ->getResult(0);
 
    if (resOrigTy != resTy)
      result = LLVM::BitcastOp::create(rewriter, loc, resOrigTy, result);
 
    rewriter.replaceOp(op, result);
    return success();
  }
};
 
class PrefetchToOCLPattern : public OpConversionPattern<PrefetchOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(PrefetchOp op, PrefetchOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    auto loc = op.getLoc();
    auto *moduleOp = op->getParentWithTrait<OpTrait::SymbolTable>();
 
    const std::string fnName{"_Z8prefetchPU3AS1Kcm"};
    Value one =
        LLVM::ConstantOp::create(rewriter, loc, rewriter.getI64Type(), 1);
    SmallVector<Value> args{op.getPtr(), one};
 
    // Annotate pointer with cache control before passing to the call.
    applyCacheControlAnnotation(rewriter, loc, op, args, moduleOp,
                                /*ptrIdx=*/0);
 
    SmallVector<Type> argTypes;
    for (auto arg : args)
      argTypes.push_back(arg.getType());
    auto funcAttr = noUnwindAttrs;
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/LLVM::ModRefInfo::NoModRef,
        /*argMem=*/LLVM::ModRefInfo::Ref,
        /*inaccessibleMem=*/LLVM::ModRefInfo::NoModRef,
        /*errnoMem=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem0=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem1=*/LLVM::ModRefInfo::NoModRef);
    funcAttr.memEffectsAttr = memAttr;
 
    createDeviceFunctionCall(rewriter, fnName,
                             LLVM::LLVMVoidType::get(rewriter.getContext()),
                             argTypes, args, {}, funcAttr, op.getOperation());
    rewriter.eraseOp(op);
    return success();
  }
};
 
class MemfenceToOCLPattern : public OpConversionPattern<MemfenceOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(MemfenceOp op, MemfenceOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    auto loc = op.getLoc();
    const std::string fnName{"atomic_work_item_fence"};
    int memScope, addrSpace;
    switch (op.getAddrspace()) {
    case xevm::AddrSpace::SHARED:
      addrSpace = 1; // CLK_LOCAL_MEM_FENCE
      break;
    case xevm::AddrSpace::GLOBAL:
      addrSpace = 2; // CLK_GLOBAL_MEM_FENCE
      break;
    default:
      // GENERIC is not supported in OpenCL
      return rewriter.notifyMatchFailure(
          op, "Fence only supports global and shared address spaces.");
    }
    switch (op.getScope()) {
    case xevm::MemScope::WORKGROUP:
      memScope = 1;
      break;
    case xevm::MemScope::DEVICE:
      memScope = 2;
      break;
    default:
      // CLUSTER and SYSTEM are not supported in OpenCL
      return rewriter.notifyMatchFailure(
          op, "Fence only supports workgroup and device memory scopes.");
    }
    Type i32Type = rewriter.getI32Type();
    Value acqRel = LLVM::ConstantOp::create(rewriter, loc, i32Type, 4);
    Value memScopeConst =
        LLVM::ConstantOp::create(rewriter, loc, i32Type, memScope);
    Value addrSpaceConst =
        LLVM::ConstantOp::create(rewriter, loc, i32Type, addrSpace);
    SmallVector<Value> args{addrSpaceConst, acqRel, memScopeConst};
    SmallVector<Type> argTypes{3, i32Type};
    createDeviceFunctionCall(rewriter, mangle(fnName, argTypes),
                             LLVM::LLVMVoidType::get(rewriter.getContext()),
                             argTypes, args, {}, noUnwindAttrs,
                             op.getOperation());
    rewriter.eraseOp(op);
    return success();
  }
};
template <typename OpType>
class LoadStorePrefetchToOCLPattern : public OpConversionPattern<OpType> {
  using OpConversionPattern<OpType>::OpConversionPattern;
  LogicalResult
  matchAndRewrite(OpType op, typename OpType::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    constexpr bool isLoad = std::is_same_v<OpType, BlockLoad2dOp>;
    constexpr bool isPrefetch = std::is_same_v<OpType, BlockPrefetch2dOp>;
 
    auto loc = op.getLoc();
    auto *moduleOp = op->template getParentWithTrait<OpTrait::SymbolTable>();
    VectorType vecType;
    bool packReg = false;
    bool transpose = false;
    if constexpr (isLoad) {
      vecType = op.getRes().getType();
      packReg = op.getPackRegister();
      transpose = op.getTranspose();
    } else if constexpr (!isPrefetch) {
      vecType = op.getStoredVal().getType();
    }
 
    auto i32Type = rewriter.getI32Type();
    Value byteCoord =
        LLVM::UndefOp::create(rewriter, loc, VectorType::get(2, i32Type));
    Value zero = LLVM::ConstantOp::create(rewriter, loc, i32Type, 0);
    Value one = LLVM::ConstantOp::create(rewriter, loc, i32Type, 1);
    byteCoord = LLVM::InsertElementOp::create(
        rewriter, loc, VectorType::get(2, i32Type), byteCoord, op.getX(), zero);
    byteCoord = LLVM::InsertElementOp::create(
        rewriter, loc, VectorType::get(2, i32Type), byteCoord, op.getY(), one);
    SmallVector<Value> args{op.getPtr(), op.getBaseWidth(), op.getBaseHeight(),
                            op.getBasePitch(), byteCoord};
 
    // Annotate pointer (args[0]) with cache control before the call.
    applyCacheControlAnnotation(rewriter, loc, op, args, moduleOp,
                                /*ptrIdx=*/0);
 
    SmallVector<Type> retTypes;
    Value spvLoadDstPtr;
    std::string funcName{"intel_sub_group_2d_block_"};
    std::string bitWidthId;
    LLVMFuncAttributeOptions funcAttr{noUnwindWillReturnAttrs};
    SmallVector<std::pair<unsigned, StringRef>, 4> paramAttrs;
    if constexpr (isPrefetch) { // Prefetch
      funcName += "prefetch";
      paramAttrs = {std::make_pair(0, LLVM::LLVMDialect::getNonNullAttrName())};
      auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
          /*other=*/LLVM::ModRefInfo::NoModRef,
          /*argMem=*/LLVM::ModRefInfo::Ref,
          /*inaccessibleMem=*/LLVM::ModRefInfo::NoModRef,
          /*errnoMem=*/LLVM::ModRefInfo::NoModRef,
          /*targetMem0=*/LLVM::ModRefInfo::NoModRef,
          /*targetMem1=*/LLVM::ModRefInfo::NoModRef);
      funcAttr = noUnwindAttrs;
      funcAttr.memEffectsAttr = memAttr;
    } else {
      auto vecElemType = vecType.getElementType();
      auto vecElemBitWidth = vecElemType.getIntOrFloatBitWidth();
      auto vecNumElems = vecType.getNumElements();
      // OpenCL Intel 2D block load has a special case
      // when element bit size is 8 and tile width is 32, which is twice
      // the subgroup size, loaded element is packed as i16.
      // To reflect this, element bit size is updated to 16 and
      // vector length is reduced by half.
      if (op.getElemSizeInBits() == 8 && op.getTileWidth() == 32) {
        vecElemBitWidth = 16;
        vecElemType = rewriter.getI16Type();
        vecNumElems = vecNumElems / 2;
      }
      Value numElems =
          LLVM::ConstantOp::create(rewriter, loc, i32Type, vecNumElems);
      auto dstOrSrcPtr = LLVM::AllocaOp::create(
          rewriter, loc, LLVM::LLVMPointerType::get(rewriter.getContext()),
          vecElemType, numElems);
      args.push_back(dstOrSrcPtr);
      if constexpr (isLoad) { // Load
        funcName += "read";
        bitWidthId = getTypeMangling(vecElemType, /*isUnsigned=*/true);
        if (packReg)
          funcName += "_transform";
        else if (transpose)
          funcName += "_transpose";
        spvLoadDstPtr = dstOrSrcPtr;
        retTypes.push_back(vecType);
        paramAttrs = {
            std::make_pair(0, LLVM::LLVMDialect::getNonNullAttrName()),
            std::make_pair(0, LLVM::LLVMDialect::getReadonlyAttrName()),
            std::make_pair(5, LLVM::LLVMDialect::getNonNullAttrName()),
            std::make_pair(5, LLVM::LLVMDialect::getWriteOnlyAttrName()),
        };
      } else { // Store
        funcName += "write";
        bitWidthId = (vecElemBitWidth == 32)
                         ? "j"
                         : ((vecElemBitWidth == 16) ? "t" : "h");
        LLVM::StoreOp::create(rewriter, loc, op.getStoredVal(), dstOrSrcPtr);
        paramAttrs = {
            std::make_pair(0, LLVM::LLVMDialect::getNonNullAttrName()),
            std::make_pair(0, LLVM::LLVMDialect::getWriteOnlyAttrName()),
            std::make_pair(5, LLVM::LLVMDialect::getNonNullAttrName()),
            std::make_pair(5, LLVM::LLVMDialect::getReadonlyAttrName()),
        };
      }
    }
 
    funcName =
        llvm::formatv("{0}_{1}b_{2}r{3}x{4}c", funcName, op.getElemSizeInBits(),
                      op.getTileHeight(), op.getTileWidth(), op.getVBlocks())
            .str();
    std::string prefetchCode("");
    if (!isPrefetch)
      prefetchCode += "P";
    funcName = llvm::formatv("_Z{0}{1}PU3AS1viiiDv2_i{2}{3}", funcName.size(),
                             funcName, prefetchCode, bitWidthId)
                   .str();
    SmallVector<Type> argTypes;
    for (auto arg : args) {
      argTypes.push_back(arg.getType());
    }
    createDeviceFunctionCall(
        rewriter, funcName, LLVM::LLVMVoidType::get(rewriter.getContext()),
        argTypes, args, paramAttrs, funcAttr, op.getOperation());
 
    if constexpr (isLoad)
      rewriter.replaceOp(
          op, LLVM::LoadOp::create(rewriter, loc, vecType, spvLoadDstPtr));
    else
      rewriter.eraseOp(op);
    return success();
  }
};
 
template <typename OpType>
class BlockLoadStore1DToOCLPattern : public OpConversionPattern<OpType> {
  using OpConversionPattern<OpType>::OpConversionPattern;
  LogicalResult
  matchAndRewrite(OpType op, typename OpType::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    constexpr bool isStore = std::is_same_v<OpType, xevm::BlockStoreOp>;
    auto loc = op.getLoc();
    auto *moduleOp = op->template getParentWithTrait<OpTrait::SymbolTable>();
 
    // Get OpenCL function name
    // https://registry.khronos.org/OpenCL/extensions/
    //         intel/cl_intel_subgroup_local_block_io.html
    std::string funcName{"intel_sub_group_block_"};
    // Value or Result type can be vector or scalar
    Type valOrResTy;
    if constexpr (isStore) {
      funcName += "write_u";
      valOrResTy = op.getVal().getType();
    } else {
      funcName += "read_u";
      valOrResTy = op.getType();
    }
    // Get element type of the vector/scalar
    VectorType vecTy = dyn_cast<VectorType>(valOrResTy);
    Type elemType = vecTy ? vecTy.getElementType() : valOrResTy;
    funcName += getTypeMangling(elemType);
    if (vecTy)
      funcName += std::to_string(vecTy.getNumElements());
    SmallVector<Type, 2> argTypes{};
    // XeVM BlockLoad/StoreOp always use signless integer types
    // but OpenCL builtins expect unsigned types
    // use unsigned types for mangling
    SmallVector<bool, 2> isUnsigned{};
    // arg0: pointer to the src/dst address
    // arg1 - only if store : vector to store
    // Prepare arguments
    SmallVector<Value, 2> args{};
    args.push_back(op.getPtr());
    argTypes.push_back(op.getPtr().getType());
    isUnsigned.push_back(true);
 
    // Annotate pointer (args[0]) with cache control.
    applyCacheControlAnnotation(rewriter, loc, op, args, moduleOp,
                                /*ptrIdx=*/0);
    // Update argTypes[0] in case the pointer type changed (it shouldn't
    // change type, but the value is now the annotated pointer).
    argTypes[0] = args[0].getType();
 
    Type retType;
    if constexpr (isStore) {
      args.push_back(op.getVal());
      argTypes.push_back(op.getVal().getType());
      isUnsigned.push_back(true);
      retType = LLVM::LLVMVoidType::get(rewriter.getContext());
    } else {
      retType = valOrResTy;
    }
    funcName = std::string("_Z") + std::to_string(funcName.size()) + funcName +
               "PU3AS" +
               std::to_string(op.getPtr().getType().getAddressSpace());
    funcName += getTypeMangling(elemType, /*isUnsigned=*/true);
    if constexpr (isStore)
      funcName += getTypeMangling(valOrResTy, /*isUnsigned=*/true);
    LLVMFuncAttributeOptions funcAttr{noUnwindWillReturnAttrs};
 
    LLVM::CallOp call =
        createDeviceFunctionCall(rewriter, funcName, retType, argTypes, args,
                                 {}, funcAttr, op.getOperation());
 
    if constexpr (isStore)
      rewriter.eraseOp(op);
    else
      rewriter.replaceOp(op, call->getResult(0));
    return success();
  }
};
 
template <typename OpType>
class LLVMLoadStoreToOCLPattern : public OpConversionPattern<OpType> {
  using OpConversionPattern<OpType>::OpConversionPattern;
  LogicalResult
  matchAndRewrite(OpType op, typename OpType::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    if (!op->hasDiscardableAttr("cache_control"))
      return failure();
 
    auto *moduleOp = op->template getParentWithTrait<OpTrait::SymbolTable>();
    std::optional<ArrayAttr> optCacheControls =
        getCacheControlMetadata(rewriter, op);
    if (!optCacheControls) {
      rewriter.modifyOpInPlace(
          op, [&]() { op->removeDiscardableAttr("cache_control"); });
      return success();
    }
 
    // Determine which operand is the pointer.
    constexpr bool isStore = std::is_same_v<OpType, LLVM::StoreOp>;
    unsigned ptrIdx = isStore ? 1 : 0;
    Value ptr = op->getOperand(ptrIdx);
 
    // Emit annotation intrinsic calls on the pointer.
    Value annotatedPtr = annotatePtrWithCacheControl(
        rewriter, op->getLoc(), ptr, *optCacheControls, moduleOp);
 
    // Replace the pointer operand with the annotated one.
    rewriter.modifyOpInPlace(op, [&]() {
      op->setOperand(ptrIdx, annotatedPtr);
      op->removeDiscardableAttr("cache_control");
    });
    return success();
  }
};
 
//===----------------------------------------------------------------------===//
// GPU index id operations
//===----------------------------------------------------------------------===//
/*
// Launch Config ops
//   dimidx - x, y, z - is fixed to i32
//   return type is set by XeVM type converter
// get_local_id
xevm::WorkitemIdXOp;
xevm::WorkitemIdYOp;
xevm::WorkitemIdZOp;
// get_local_size
xevm::WorkgroupDimXOp;
xevm::WorkgroupDimYOp;
xevm::WorkgroupDimZOp;
// get_group_id
xevm::WorkgroupIdXOp;
xevm::WorkgroupIdYOp;
xevm::WorkgroupIdZOp;
// get_num_groups
xevm::GridDimXOp;
xevm::GridDimYOp;
xevm::GridDimZOp;
// get_global_id : to be added if needed
*/
 
// Helpers to get the OpenCL function name and dimension argument for each op.
static std::pair<StringRef, int64_t> getConfig(xevm::WorkitemIdXOp) {
  return {"get_local_id", 0};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkitemIdYOp) {
  return {"get_local_id", 1};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkitemIdZOp) {
  return {"get_local_id", 2};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkgroupDimXOp) {
  return {"get_local_size", 0};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkgroupDimYOp) {
  return {"get_local_size", 1};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkgroupDimZOp) {
  return {"get_local_size", 2};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkgroupIdXOp) {
  return {"get_group_id", 0};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkgroupIdYOp) {
  return {"get_group_id", 1};
}
static std::pair<StringRef, int64_t> getConfig(xevm::WorkgroupIdZOp) {
  return {"get_group_id", 2};
}
static std::pair<StringRef, int64_t> getConfig(xevm::GridDimXOp) {
  return {"get_num_groups", 0};
}
static std::pair<StringRef, int64_t> getConfig(xevm::GridDimYOp) {
  return {"get_num_groups", 1};
}
static std::pair<StringRef, int64_t> getConfig(xevm::GridDimZOp) {
  return {"get_num_groups", 2};
}
/// Replace `xevm.*` with an `llvm.call` to the corresponding OpenCL func with
/// a constant argument for the dimension - x, y or z.
template <typename OpType>
class LaunchConfigOpToOCLPattern : public OpConversionPattern<OpType> {
  using OpConversionPattern<OpType>::OpConversionPattern;
  LogicalResult
  matchAndRewrite(OpType op, typename OpType::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    Location loc = op->getLoc();
    auto [baseName, dim] = getConfig(op);
    Type dimTy = rewriter.getI32Type();
    Value dimVal = LLVM::ConstantOp::create(rewriter, loc, dimTy,
                                            static_cast<int64_t>(dim));
    std::string func = mangle(baseName, {dimTy}, {true});
    Type resTy = op.getType();
    auto call =
        createDeviceFunctionCall(rewriter, func, resTy, {dimTy}, {dimVal}, {},
                                 noUnwindWillReturnAttrs, op.getOperation());
    constexpr auto noModRef = LLVM::ModRefInfo::NoModRef;
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/noModRef,
        /*argMem=*/noModRef, /*inaccessibleMem=*/noModRef,
        /*errnoMem=*/noModRef,
        /*targetMem0=*/noModRef,
        /*targetMem1=*/noModRef);
    call.setMemoryEffectsAttr(memAttr);
    rewriter.replaceOp(op, call);
    return success();
  }
};
 
/*
// Subgroup ops
// get_sub_group_local_id
xevm::LaneIdOp;
// get_sub_group_id
xevm::SubgroupIdOp;
// get_sub_group_size
xevm::SubgroupSizeOp;
// get_num_sub_groups : to be added if needed
*/
 
// Helpers to get the OpenCL function name for each op.
static StringRef getConfig(xevm::LaneIdOp) { return "get_sub_group_local_id"; }
static StringRef getConfig(xevm::SubgroupIdOp) { return "get_sub_group_id"; }
static StringRef getConfig(xevm::SubgroupSizeOp) {
  return "get_sub_group_size";
}
template <typename OpType>
class SubgroupOpWorkitemOpToOCLPattern : public OpConversionPattern<OpType> {
  using OpConversionPattern<OpType>::OpConversionPattern;
  LogicalResult
  matchAndRewrite(OpType op, typename OpType::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    std::string func = mangle(getConfig(op).str(), {});
    Type resTy = op.getType();
    auto call =
        createDeviceFunctionCall(rewriter, func, resTy, {}, {}, {},
                                 noUnwindWillReturnAttrs, op.getOperation());
    constexpr auto noModRef = LLVM::ModRefInfo::NoModRef;
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/noModRef,
        /*argMem=*/noModRef, /*inaccessibleMem=*/noModRef,
        /*errnoMem=*/noModRef,
        /*targetMem0=*/noModRef,
        /*targetMem1=*/noModRef);
    call.setMemoryEffectsAttr(memAttr);
    rewriter.replaceOp(op, call);
    return success();
  }
};
 
/// SPIR-V, and so the OpenCL builtins the float conversions call into, only
/// provides vector types of 2, 3, 4, 8 and 16 elements.
static bool isSupportedSPIRVVectorLength(int64_t numElements) {
  return llvm::is_contained({2, 3, 4, 8, 16}, numElements);
}
 
/// Bitcasts `val` to `ty` unless it already has that type.
static Value castIfNeeded(ConversionPatternRewriter &rewriter, Location loc,
                          Type ty, Value val) {
  if (val.getType() == ty)
    return val;
  return LLVM::BitcastOp::create(rewriter, loc, ty, val);
}
 
/// Selects `numElements` leading elements of the vector `val`. Used to drop the
/// padding the 3 element case needs, as the hardware conversions work on whole
/// pairs of elements.
static Value takeLeadingElements(ConversionPatternRewriter &rewriter,
                                 Location loc, Value val, int64_t numElements) {
  auto vecTy = cast<VectorType>(val.getType());
  if (vecTy.getNumElements() == numElements)
    return val;
  SmallVector<int32_t> mask =
      llvm::to_vector(llvm::seq<int32_t>(0, static_cast<int32_t>(numElements)));
  return LLVM::ShuffleVectorOp::create(rewriter, loc, val, val, mask);
}
 
//
// Note: TruncfToOCLPattern and ExtfToOCLPattern does not lower to OpenCL API
// calls as there are not official ones yet. They are lowered directly to Intel
// graphics compiler built in functions.
// See
// https://github.com/intel/intel-graphics-compiler/tree/master/IGC/BiFModule/Implementation/SPV_INTEL_fp_conversions
// for builtin function usage. The folder contains implementation of
// experimental SPIR-V extension for truncf and extf using builtin functions.
// TODO: Move to OpenCL API call once they are available.
//
 
class TruncfToOCLPattern : public OpConversionPattern<TruncfOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(TruncfOp op, TruncfOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    // Supported source and result types are resticted for now.
    auto srcEtype = op.getSrcEtype().getEtype();
    auto dstEtype = op.getDstEtype().getEtype();
    // The conversions are provided as OpenCL builtins, one per vector length,
    // so only the SPIR-V vector lengths can be lowered. A wider conversion has
    // to be split into several ops before reaching this pattern.
    //
    // Scalar case is not supported until usage case become clear.
    auto vecSrcTy = dyn_cast<VectorType>(op.getSrc().getType());
    if (!vecSrcTy) {
      return rewriter.notifyMatchFailure(op, "Scalar src is not supported.");
    }
    int64_t numElements = vecSrcTy.getNumElements();
    if (!isSupportedSPIRVVectorLength(numElements))
      return rewriter.notifyMatchFailure(
          op, "src vector length must be 2, 3, 4, 8 or 16");
    // The destination is scalar only where the packed values fit in one byte,
    // which SPIR-V spells as a scalar rather than a one element vector.
    Type dstTy = op.getDst().getType();
    Location loc = op.getLoc();
    Value src = op.getSrc();
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/LLVM::ModRefInfo::NoModRef,
        /*argMem=*/LLVM::ModRefInfo::NoModRef,
        /*inaccessibleMem=*/LLVM::ModRefInfo::NoModRef,
        /*errnoMem=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem0=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem1=*/LLVM::ModRefInfo::NoModRef);
    auto funcAttrs = convergentNoUnwindWillReturnAttrs;
    funcAttrs.memEffectsAttr = memAttr;
 
    // Handle the case where dst type is fp4 first.
    if (dstEtype == TruncfDstElemTypes::E2M1) {
      // `__builtin_IB_dnscl_{hf16,bf16}(uint a, uint b, convert_to, mode)`
      // takes two dwords, each holding two source elements, and packs each pair
      // into one byte of the result dword. `mode` picks which bytes of that
      // dword are written: mode 0 writes bytes 0 and 2, mode 2 writes bytes 1
      // and 3. Two calls with complementary modes therefore OR together into
      // one fully packed dword covering eight source elements.
      //
      // A pair of elements is the conversion granularity, so an odd length is
      // padded up and the spare nibble left undefined.
      constexpr int kDnsclConvertToE2M1 = 1;
      constexpr int kDnsclModeBytes02 = 0;
      constexpr int kDnsclModeBytes13 = 2;
      // One dword lane per element pair, and one result byte per lane. The op
      // verifier has already checked that the destination is exactly that wide.
      int64_t numLanes = llvm::divideCeil(numElements, 2);
 
      Type i32Ty = rewriter.getI32Type();
      Type i8Ty = rewriter.getI8Type();
      // Pad an odd length up to a whole number of pairs, then view the source
      // as dword lanes.
      Value padded = src;
      if (numElements != numLanes * 2) {
        SmallVector<int32_t> mask = llvm::to_vector(
            llvm::seq<int32_t>(0, static_cast<int32_t>(numElements)));
        // The padding element is never read back, so any valid index will do.
        mask.append(static_cast<size_t>(numLanes * 2 - numElements), 0);
        padded = LLVM::ShuffleVectorOp::create(rewriter, loc, src, src, mask);
      }
      // A single lane is passed as a bare i32 rather than a one element vector,
      // which SPIR-V has no type for.
      Value laneVec;
      if (numLanes > 1)
        laneVec = LLVM::BitcastOp::create(
            rewriter, loc, VectorType::get(numLanes, i32Ty), padded);
      else
        laneVec = LLVM::BitcastOp::create(rewriter, loc, i32Ty, padded);
      auto getLane = [&](int64_t idx) -> Value {
        if (numLanes == 1)
          return laneVec;
        Value pos =
            LLVM::ConstantOp::create(rewriter, loc, rewriter.getI32Type(), idx);
        return LLVM::ExtractElementOp::create(rewriter, loc, laneVec, pos)
            ->getResult(0);
      };
 
      std::string fnName = "__builtin_IB_dnscl_";
      fnName += (srcEtype == TruncfSrcElemTypes::F16) ? "hf16" : "bf16";
      Value convertTo =
          LLVM::ConstantOp::create(rewriter, loc, i32Ty, kDnsclConvertToE2M1);
      auto genDnscl = [&](Value lo, Value hi, int mode) -> Value {
        Value modeVal = LLVM::ConstantOp::create(rewriter, loc, i32Ty, mode);
        SmallVector<Type> argTypes{lo.getType(), hi.getType(),
                                   convertTo.getType(), modeVal.getType()};
        SmallVector<Value> args{lo, hi, convertTo, modeVal};
        return createDeviceFunctionCall(rewriter, fnName, i32Ty, argTypes, args,
                                        {}, funcAttrs, op.getOperation())
            ->getResult(0);
      };
 
      Value result;
      if (numLanes <= 2) {
        // Fewer than four lanes cannot fill a dword, so a single call is made
        // and the written bytes, 0 and 2, are compacted afterwards.
        Value lo = getLane(0);
        Value hi =
            numLanes == 2
                ? getLane(1)
                : LLVM::UndefOp::create(rewriter, loc, i32Ty)->getResult(0);
        Value dword = genDnscl(lo, hi, kDnsclModeBytes02);
        if (numLanes == 1) {
          // A single byte, so the low one, is all that is kept.
          result = LLVM::TruncOp::create(rewriter, loc, i8Ty, dword);
        } else {
          Value bytes = LLVM::BitcastOp::create(
              rewriter, loc, VectorType::get(4, i8Ty), dword);
          result = LLVM::ShuffleVectorOp::create(rewriter, loc, bytes, bytes,
                                                 ArrayRef<int32_t>{0, 2});
        }
      } else {
        // Four lanes, eight source elements, per fully packed dword.
        SmallVector<Value> dwords;
        for (int64_t base = 0; base < numLanes; base += 4) {
          // Each lane is bound to a name first: `getLane` builds ops, and the
          // order of evaluation within an argument list is unspecified, which
          // would otherwise leave the order of the emitted ops up to the host
          // compiler.
          Value lane0 = getLane(base);
          Value lane2 = getLane(base + 2);
          Value even = genDnscl(lane0, lane2, kDnsclModeBytes02);
          Value lane1 = getLane(base + 1);
          Value lane3 = getLane(base + 3);
          Value odd = genDnscl(lane1, lane3, kDnsclModeBytes13);
          dwords.push_back(LLVM::OrOp::create(rewriter, loc, even, odd));
        }
        if (dwords.size() == 1) {
          result = dwords.front();
        } else {
          Type packedTy = VectorType::get(dwords.size(), i32Ty);
          result = LLVM::UndefOp::create(rewriter, loc, packedTy);
          for (auto [idx, dword] : llvm::enumerate(dwords)) {
            Value pos = LLVM::ConstantOp::create(rewriter, loc, i32Ty, idx);
            result =
                LLVM::InsertElementOp::create(rewriter, loc, result, dword, pos)
                    ->getResult(0);
          }
        }
      }
      rewriter.replaceOp(op, castIfNeeded(rewriter, loc, dstTy, result));
      return success();
    }
 
    // Handle the case where dst type is fp8.
    // The fp8 conversions come as one builtin per vector length, so the length
    // is simply appended to the builtin name.
    std::string lenSuffix = std::to_string(numElements);
    // BF16 type needs some preprocessing before conversion,
    // First extended to F32 and then truncated to F16.
    if (srcEtype == TruncfSrcElemTypes::BF16) {
      // Step 1: Extend to F32
      // Use floatN __builtin_IB_bftof_N(shortN)
      src = LLVM::BitcastOp::create(
          rewriter, op.getLoc(),
          VectorType::get(vecSrcTy.getShape(), rewriter.getI16Type()), src);
      std::string fnName = "__builtin_IB_bftof_" + lenSuffix;
      SmallVector<Type> argTypes{src.getType()};
      SmallVector<Value> args{src};
      Type resTy = VectorType::get(vecSrcTy.getShape(), rewriter.getF32Type());
      src = createDeviceFunctionCall(rewriter, fnName, resTy, argTypes, args,
                                     {}, funcAttrs, op.getOperation())
                ->getResult(0);
      // Step 2: Truncf to F16
      // Use halfN convert_halfN(floatN)
      std::string truncFnName = "convert_half" + lenSuffix;
      SmallVector<Type> truncArgTypes{src.getType()};
      SmallVector<Value> truncArgs{src};
      truncFnName = mangle(truncFnName, truncArgTypes);
      resTy = VectorType::get(vecSrcTy.getShape(), rewriter.getF16Type());
      src =
          createDeviceFunctionCall(rewriter, truncFnName, resTy, truncArgTypes,
                                   truncArgs, {}, funcAttrs, op.getOperation())
              ->getResult(0);
    }
    if (dstEtype == TruncfDstElemTypes::BF8) { // Float8E5M2Type
      // Use charN __builtin_IB_hftobf8_N(halfN)
      std::string fnName = "__builtin_IB_hftobf8_" + lenSuffix;
      SmallVector<Type> argTypes{src.getType()};
      SmallVector<Value> args{src};
      Value result =
          createDeviceFunctionCall(rewriter, fnName, dstTy, argTypes, args, {},
                                   funcAttrs, op.getOperation())
              ->getResult(0);
 
      rewriter.replaceOp(op, result);
    } else if (dstEtype == TruncfDstElemTypes::F8) { // Float8E4M3FNType
      // Use charN __builtin_IB_hftohf8_N(halfN)
      std::string fnName = "__builtin_IB_hftohf8_" + lenSuffix;
      SmallVector<Type> argTypes{src.getType()};
      SmallVector<Value> args{src};
      Value result =
          createDeviceFunctionCall(rewriter, fnName, dstTy, argTypes, args, {},
                                   funcAttrs, op.getOperation())
              ->getResult(0);
 
      rewriter.replaceOp(op, result);
    } else {
      return rewriter.notifyMatchFailure(
          op, "Unsupported src, dst element type pair.");
    }
    return success();
  }
};
 
class ExtfToOCLPattern : public OpConversionPattern<ExtfOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(ExtfOp op, ExtfOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    // `xevm.extf` is the inverse of `xevm.truncf`. Supported source and result
    // types are restricted for now, mirroring the truncf lowering.
    auto srcEtype = op.getSrcEtype().getEtype();
    auto dstEtype = op.getDstEtype().getEtype();
    // The source is scalar only where the packed values fit in one byte, which
    // SPIR-V spells as a scalar rather than a one element vector.
    Type srcTy = op.getSrc().getType();
    // Scalar dst is not supported until usage case become clear.
    auto vecDstTy = dyn_cast<VectorType>(op.getDst().getType());
    if (!vecDstTy)
      return rewriter.notifyMatchFailure(op, "Scalar dst is not supported.");
    // As for truncf, one builtin exists per SPIR-V vector length.
    int64_t numElements = vecDstTy.getNumElements();
    if (!isSupportedSPIRVVectorLength(numElements))
      return rewriter.notifyMatchFailure(
          op, "dst vector length must be 2, 3, 4, 8 or 16");
    Location loc = op.getLoc();
    Value src = op.getSrc();
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/LLVM::ModRefInfo::NoModRef,
        /*argMem=*/LLVM::ModRefInfo::NoModRef,
        /*inaccessibleMem=*/LLVM::ModRefInfo::NoModRef,
        /*errnoMem=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem0=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem1=*/LLVM::ModRefInfo::NoModRef);
    auto funcAttrs = convergentNoUnwindWillReturnAttrs;
    funcAttrs.memEffectsAttr = memAttr;
 
    // Handle the case where src type is fp4 (e2m1) first.
    if (srcEtype == ExtfSrcElemTypes::E2M1) {
      // Two fp4 values are packed per source byte, and one builtin exists per
      // source byte count:
      //   uint16 __builtin_IB_shfl_idx4_lut(int lut_index)
      //   uint   __builtin_IB_shfl_idx4_to_fp16_packed(uint16 lut, char src)
      //   uintN  __builtin_IB_shfl_idx4_to_fp16_N_packed(uint16 lut, charN src)
      // Each returns one dword, holding two f16/bf16 values, per source byte.
      // The lookup table selects the target format:
      //   7 = e2m1 -> f16, 5 = e2m1 -> bf16.
      //
      // A byte is the conversion granularity, so an odd length reads one spare
      // value that is dropped afterwards. The op verifier has already checked
      // that the source is exactly as wide as those bytes.
      int64_t numBytes = llvm::divideCeil(numElements, 2);
      constexpr int kLutE2M1ToF16 = 7;
      constexpr int kLutE2M1ToBF16 = 5;
      int lutIndex =
          (dstEtype == ExtfDstElemTypes::F16) ? kLutE2M1ToF16 : kLutE2M1ToBF16;
      Value lutIdx = LLVM::ConstantOp::create(rewriter, loc,
                                              rewriter.getI32Type(), lutIndex);
      Type lutTy = VectorType::get(16, rewriter.getI32Type());
      Value lut =
          createDeviceFunctionCall(rewriter, "__builtin_IB_shfl_idx4_lut",
                                   lutTy, {lutIdx.getType()}, {lutIdx}, {},
                                   funcAttrs, op.getOperation())
              ->getResult(0);
      // A single byte is passed as a bare i8, and one dword returned as a bare
      // i32, rather than as one element vectors SPIR-V has no type for.
      Type i8Ty = rewriter.getI8Type();
      Type i32Ty = rewriter.getI32Type();
      std::string fnName = "__builtin_IB_shfl_idx4_to_fp16_";
      Type argTy, packedResTy;
      if (numBytes == 1) {
        argTy = i8Ty;
        packedResTy = i32Ty;
      } else {
        fnName += std::to_string(numBytes) + "_";
        argTy = VectorType::get(numBytes, i8Ty);
        packedResTy = VectorType::get(numBytes, i32Ty);
      }
      fnName += "packed";
      SmallVector<Type> convArgTypes{lut.getType(), argTy};
      SmallVector<Value> convArgs{lut, castIfNeeded(rewriter, loc, argTy, src)};
      Value result =
          createDeviceFunctionCall(rewriter, fnName, packedResTy, convArgTypes,
                                   convArgs, {}, funcAttrs, op.getOperation())
              ->getResult(0);
      // The builtin returns the f16/bf16 bits packed as i32, bitcast to the
      // f16/bf16 dst type and drop the padding an odd length produced.
      Type wideTy = VectorType::get(numBytes * 2, vecDstTy.getElementType());
      result = LLVM::BitcastOp::create(rewriter, loc, wideTy, result);
      result = takeLeadingElements(rewriter, loc, result, numElements);
      rewriter.replaceOp(op, result);
      return success();
    }
 
    // Handle the case where src type is fp8 (bf8/hf8). One fp8 value per source
    // byte, so source and destination lengths match.
    auto vecSrcTy = dyn_cast<VectorType>(srcTy);
    if (!vecSrcTy || vecSrcTy.getNumElements() != numElements)
      return rewriter.notifyMatchFailure(
          op, "fp8 src and dst must have the same number of elements");
    std::string lenSuffix = std::to_string(numElements);
 
    // Step 1: Extend fp8 (bf8/hf8) to F16.
    //   bf8 -> half: halfN __builtin_IB_bf8tohf_N(charN)
    //   hf8 -> half: halfN __builtin_IB_hf8tohf_N(charN)
    std::string fnName = (srcEtype == ExtfSrcElemTypes::BF8)
                             ? "__builtin_IB_bf8tohf_"
                             : "__builtin_IB_hf8tohf_";
    fnName += lenSuffix;
    Type f16Ty = VectorType::get(vecSrcTy.getShape(), rewriter.getF16Type());
    SmallVector<Type> argTypes{src.getType()};
    SmallVector<Value> args{src};
    Value result =
        createDeviceFunctionCall(rewriter, fnName, f16Ty, argTypes, args, {},
                                 funcAttrs, op.getOperation())
            ->getResult(0);
 
    // When the destination is F16, we are done.
    if (dstEtype == ExtfDstElemTypes::F16) {
      rewriter.replaceOp(op, result);
      return success();
    }
 
    // BF16 destination needs some postprocessing.
    // First extend F16 to F32 and then truncate to BF16.
    // Step 2: Extend to F32.
    // Use floatN convert_floatN(halfN)
    std::string convFnName = "convert_float" + lenSuffix;
    SmallVector<Type> convArgTypes{result.getType()};
    SmallVector<Value> convArgs{result};
    convFnName = mangle(convFnName, convArgTypes);
    Type f32Ty = VectorType::get(vecSrcTy.getShape(), rewriter.getF32Type());
    result =
        createDeviceFunctionCall(rewriter, convFnName, f32Ty, convArgTypes,
                                 convArgs, {}, funcAttrs, op.getOperation())
            ->getResult(0);
    // Step 3: Truncate F32 to BF16.
    // Use shortN __builtin_IB_ftobf_N(floatN)
    std::string ftobfFnName = "__builtin_IB_ftobf_" + lenSuffix;
    SmallVector<Type> ftobfArgTypes{result.getType()};
    SmallVector<Value> ftobfArgs{result};
    Type i16Ty = VectorType::get(vecSrcTy.getShape(), rewriter.getI16Type());
    result =
        createDeviceFunctionCall(rewriter, ftobfFnName, i16Ty, ftobfArgTypes,
                                 ftobfArgs, {}, funcAttrs, op.getOperation())
            ->getResult(0);
    // The builtin returns the bf16 bits as i16, bitcast to the bf16 dst type.
    result = LLVM::BitcastOp::create(rewriter, op.getLoc(), vecDstTy, result);
    rewriter.replaceOp(op, result);
    return success();
  }
};
 
class MMAMxToOCLPattern : public OpConversionPattern<MMAMxOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(MMAMxOp op, MMAMxOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    if (!op.getC()) {
      return rewriter.notifyMatchFailure(op, "OCL requires C operand");
    }
    auto precisionC = op.getTypes().getC();
    auto precisionD = op.getTypes().getD();
    if (precisionC != precisionD) {
      return rewriter.notifyMatchFailure(op, "type of C and D need to match");
    }
 
    constexpr uint32_t bitWidthPackedA{16};
    constexpr uint32_t bitWidthPackedB{32};
    auto loc = op.getLoc();
 
    auto castIfNeeded = [&](Value val, Type packedType) -> Value {
      VectorType origTy = cast<VectorType>(val.getType());
      const uint32_t vecBitSize =
          origTy.getNumElements() *
          origTy.getElementType().getIntOrFloatBitWidth();
      VectorType newTy = VectorType::get(
          vecBitSize / packedType.getIntOrFloatBitWidth(), packedType);
      if (origTy != newTy)
        val = LLVM::BitcastOp::create(rewriter, loc, newTy, val);
      return val;
    };
 
    Value a = op.getA();
    Type packedAType = (op.getTypes().getA() == xevm::ElemType::TF32)
                           ? cast<Type>(rewriter.getF32Type())
                           : rewriter.getIntegerType(bitWidthPackedA);
    a = castIfNeeded(a, packedAType);
 
    Value b = op.getB();
    Type packedBType = (op.getTypes().getB() == xevm::ElemType::TF32)
                           ? cast<Type>(rewriter.getF32Type())
                           : rewriter.getIntegerType(bitWidthPackedB);
    b = castIfNeeded(b, packedBType);
 
    Value c = op.getC();
    VectorType cOrigTy = cast<VectorType>(c.getType());
    VectorType resOrigTy = cast<VectorType>(op->getResultTypes()[0]);
    assert(cOrigTy == resOrigTy && "Accumulator and result type mismatch");
    // OCL builtins encode bfloat16 as int16
    VectorType cTy =
        cOrigTy.getElementType().isBF16()
            ? VectorType::get(cOrigTy.getShape(), rewriter.getIntegerType(16))
            : cOrigTy;
    VectorType resTy = cTy;
    if (cOrigTy != cTy)
      c = LLVM::BitcastOp::create(rewriter, loc, cTy, c);
 
    std::string fnName =
        llvm::formatv("__builtin_IB_sub_group16_bdpas_{0}_{1}_{2}_{3}_8_8",
                      builtinElemType(op.getTypes().getD()),
                      builtinElemType(op.getTypes().getC()),
                      builtinElemType(op.getTypes().getA()),
                      builtinElemType(op.getTypes().getB()))
            .str();
    auto scaleA = op.getScaleA();
    auto scaleB = op.getScaleB();
    SmallVector<Type> argTypes{cTy, a.getType(), b.getType(), scaleA.getType(),
                               scaleB.getType()};
    SmallVector<Value> args{c, a, b, scaleA, scaleB};
 
    auto memAttr = rewriter.getAttr<LLVM::MemoryEffectsAttr>(
        /*other=*/LLVM::ModRefInfo::NoModRef,
        /*argMem=*/LLVM::ModRefInfo::NoModRef,
        /*inaccessibleMem=*/LLVM::ModRefInfo::NoModRef,
        /*errnoMem=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem0=*/LLVM::ModRefInfo::NoModRef,
        /*targetMem1=*/LLVM::ModRefInfo::NoModRef);
    auto funcAttrs = convergentNoUnwindWillReturnAttrs;
    funcAttrs.memEffectsAttr = memAttr;
    Value result =
        createDeviceFunctionCall(rewriter, fnName, resTy, argTypes, args, {},
                                 funcAttrs, op.getOperation())
            ->getResult(0);
 
    if (resOrigTy != resTy)
      result = LLVM::BitcastOp::create(rewriter, loc, resOrigTy, result);
 
    rewriter.replaceOp(op, result);
    return success();
  }
};
 
// Lowers `xevm.bitcast_shuffle` to a call to the IGC intrinsic
// `llvm.genx.GenISA.SubgroupBitcastShuffle`, which is overloaded on both the
// result and the operand type. E.g. a `vector<4xi8>` -> `vector<2xi16>` shuffle
// becomes a call to
// `llvm.genx.GenISA.SubgroupBitcastShuffle.v2i16.v4i8`.
//
// Only integer types reach here: the op accepts nothing else, so a producer
// holding floating point data bitcasts it to a same-width integer beforehand.
class BitcastShuffleToGenISAPattern
    : public OpConversionPattern<BitcastShuffleOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(BitcastShuffleOp op, BitcastShuffleOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    Type srcTy = op.getSrc().getType();
    Type resTy = op.getRes().getType();
 
    std::string fnName = "llvm.genx.GenISA.SubgroupBitcastShuffle." +
                         getGenISATypeMangling(resTy) + "." +
                         getGenISATypeMangling(srcTy);
 
    Value result = createDeviceFunctionCall(
                       rewriter, fnName, resTy, {srcTy}, {adaptor.getSrc()}, {},
                       convergentNoUnwindWillReturnAttrs, op.getOperation())
                       ->getResult(0);
 
    rewriter.replaceOp(op, result);
    return success();
  }
};
 
class AllocaToGlobalPattern : public OpConversionPattern<LLVM::AllocaOp> {
  using OpConversionPattern::OpConversionPattern;
  LogicalResult
  matchAndRewrite(LLVM::AllocaOp op, LLVM::AllocaOp::Adaptor adaptor,
                  ConversionPatternRewriter &rewriter) const override {
    auto ptrType = cast<LLVM::LLVMPointerType>(op.getType());
    auto addrSpace = ptrType.getAddressSpace();
    if (addrSpace != 3)
      return failure();
    auto symTable = op->getParentWithTrait<OpTrait::SymbolTable>();
    if (!symTable)
      return failure();
    Block *moduleBody;
    if (ModuleOp mod = dyn_cast<ModuleOp>(*symTable)) {
      moduleBody = mod.getBody();
    } else if (gpu::GPUModuleOp gpuMod =
                   dyn_cast<gpu::GPUModuleOp>(*symTable)) {
      moduleBody = gpuMod.getBody();
    } else {
      return failure();
    }
    auto val = op.getArraySize();
    APInt cst;
    if (!matchPattern(val, m_ConstantInt(&cst)))
      return failure();
    auto loc = op.getLoc();
    auto globalType = LLVM::LLVMArrayType::get(
        rewriter.getContext(), op.getElemType(), cst.getZExtValue());
    LLVM::GlobalOp globalVar;
    {
      OpBuilder::InsertionGuard guard(rewriter);
      rewriter.setInsertionPointToStart(moduleBody);
      auto alignment = op.getAlignment();
      globalVar = LLVM::GlobalOp::create(
          rewriter, loc, globalType, /*isConstant=*/false,
          /*linkage=*/LLVM::Linkage::Internal,
          /*name=*/std::string("__global_alloca_") +
              std::to_string(getNextGlobalIdx()),
          /*value=*/Attribute(),
          /*alignment=*/alignment ? *alignment : 0, /*addrSpace=*/addrSpace);
    }
    rewriter.replaceOpWithNewOp<LLVM::AddressOfOp>(op, globalVar);
    return success();
  }
 
private:
  static unsigned getNextGlobalIdx() {
    static unsigned globalIdx = 0;
    return globalIdx++;
  }
};
 
// Checks if shufflevector is used as a way to extract a contiguous slice
// from a vector.
// - source vector V2 is either the same as V1, or a poison/undef value. In
//   both cases the mask can only meaningfully address elements of V1, which
//   the mask checks below enforce.
// - mask size is not greater than the source vector size
// - mask values represent a sequence of consecutive increasing numbers
//   that stay in bounds of the source vector when used for indexing.
static bool isExtractingContiguousSlice(LLVM::ShuffleVectorOp op) {
  if (op.getV1() != op.getV2() &&
      !isa_and_present<LLVM::PoisonOp, LLVM::UndefOp>(
          op.getV2().getDefiningOp()))
    return false;
  auto maskAttr = op.getMask();
  int64_t maskSize = static_cast<int64_t>(maskAttr.size());
  int64_t sourceSize = op.getV1().getType().getNumElements();
  if (maskSize > sourceSize)
    return false;
  int64_t firstIndex = maskAttr[0];
  if (firstIndex < 0 || firstIndex >= sourceSize)
    return false;
  for (int64_t i = 1; i < maskSize; ++i) {
    int64_t index = maskAttr[i];
    if (index != firstIndex + i)
      return false;
    if (index >= sourceSize)
      return false;
  }
  return true;
}
 
// Input vector of a shuffle vector op extracting a contiguous slice is an
// illegal vector in SPIRV kernel if the vector size is > 16 elements.
// To legalize this case, keep applying the following transformations until no
// more match:
//   1. keep hoisting the shuffle vector op past unary element-wise operations
//       start with fpext, fptrunc and bitcast for now.
//   2. merge with another shuffle vector op
//   3. merge with load as a smaller load
class HandleVectorExtractPattern
    : public OpRewritePattern<LLVM::ShuffleVectorOp> {
  using OpRewritePattern<LLVM::ShuffleVectorOp>::OpRewritePattern;
 
  void initialize() { setHasBoundedRewriteRecursion(); }
 
  LogicalResult matchAndRewrite(LLVM::ShuffleVectorOp op,
                                PatternRewriter &rewriter) const override {
 
    if (!isExtractingContiguousSlice(op))
      return failure();
 
    auto mask = op.getMask();
    auto loc = op.getLoc();
    auto ty = op.getType();
    // Check source operand to determine rewrite pattern.
    auto src = op.getV1();
    // 1. Hoist past unary element-wise operations
    if (auto srcOp = src.getDefiningOp()) {
      if (isa<LLVM::FPExtOp>(srcOp) || isa<LLVM::FPTruncOp>(srcOp)) {
        Value srcInput = srcOp->getOperand(0);
        // Create new shuffle vector op with unary input as source.
        auto srcVecTy = dyn_cast<VectorType>(srcInput.getType());
        if (!srcVecTy)
          return failure();
        auto newShuffleVecTy =
            VectorType::get(mask.size(), srcVecTy.getElementType());
        auto newShuffle = LLVM::ShuffleVectorOp::create(
            rewriter, loc, newShuffleVecTy, srcInput, srcInput, mask);
        // Create new unary op with new shuffle as input.
        Value newUnaryOp;
        if (isa<LLVM::FPExtOp>(srcOp)) {
          newUnaryOp = LLVM::FPExtOp::create(rewriter, loc, ty, newShuffle);
        } else {
          newUnaryOp = LLVM::FPTruncOp::create(rewriter, loc, ty, newShuffle);
        }
        rewriter.replaceOp(op, newUnaryOp);
      } else if (isa<LLVM::BitcastOp>(srcOp)) {
        Value srcInput = srcOp->getOperand(0);
        // Create new shuffle vector op with unary input as source. A bitcast
        // from a scalar has no slice to rewrite in terms of.
        auto srcInputVecTy = dyn_cast<VectorType>(srcInput.getType());
        auto srcResVecTy = dyn_cast<VectorType>(srcOp->getResult(0).getType());
        if (!srcInputVecTy || !srcResVecTy)
          return failure();
        auto srcInputSize = srcInputVecTy.getNumElements();
        auto srcResSize = srcResVecTy.getNumElements();
        auto maskSize = static_cast<int32_t>(mask.size());
        if (srcInputSize > srcResSize) {
          return failure();
        }
        if (srcResSize % srcInputSize != 0) {
          return failure();
        }
        auto maskScale = srcResSize / srcInputSize;
        if (maskScale != 1) {
          // The slice has to start at, and cover, whole source elements to be
          // expressible in terms of the bitcast source.
          if (mask[0] % maskScale != 0 || maskSize % maskScale != 0) {
            return failure();
          }
          // Create a new mask that maps to the source vector
          SmallVector<int32_t> newMask;
          int32_t newMaskSize = maskSize / maskScale;
          int32_t maskStart = mask[0] / maskScale;
          for (int32_t i = 0; i < newMaskSize; ++i) {
            newMask.push_back(maskStart + i);
          }
          mask = newMask;
        }
        auto newShuffleVecTy = VectorType::get(
            static_cast<int64_t>(mask.size()), srcInputVecTy.getElementType());
        auto newShuffle = LLVM::ShuffleVectorOp::create(
            rewriter, loc, newShuffleVecTy, srcInput, srcInput, mask);
        // Create new unary op with new shuffle as input.
        auto newBitcast =
            LLVM::BitcastOp::create(rewriter, loc, ty, newShuffle);
        rewriter.replaceOp(op, newBitcast);
      } else if (isa<LLVM::ShuffleVectorOp>(srcOp)) {
        // 2. Merge with source shuffle vector op if, the source op is
        //    also extracting a contigous slice and create a new
        //    shuffle vector op directly from the source of
        //    the first shuffle.
        auto srcShuffle = cast<LLVM::ShuffleVectorOp>(srcOp);
        if (!isExtractingContiguousSlice(srcShuffle))
          return failure();
        auto srcMask = srcShuffle.getMask();
        SmallVector<int32_t> combinedMask;
        for (auto index : mask) {
          combinedMask.push_back(srcMask[index]);
        }
        auto newShuffle = LLVM::ShuffleVectorOp::create(
            rewriter, loc, ty, srcShuffle.getV1(), srcShuffle.getV1(),
            DenseI32ArrayAttr::get(rewriter.getContext(), combinedMask));
        rewriter.replaceOp(op, newShuffle);
      } else if (isa<LLVM::LoadOp>(srcOp)) {
        // 3. Merge with load as a smaller load
        auto loadOp = cast<LLVM::LoadOp>(srcOp);
        auto loadPtr = loadOp.getAddr();
        auto loadAddrSpace = loadPtr.getType().getAddressSpace();
        if (loadAddrSpace != 0)
          return failure();
        auto loadTy = dyn_cast<VectorType>(loadOp.getType());
        if (!loadTy)
          return failure();
        auto elemTy = loadTy.getElementType();
        auto firstIndex = mask[0];
        auto newVecTy = VectorType::get(mask.size(), elemTy);
        // GEPOp is needed if first index is not zero
        if (firstIndex) {
          auto newPtr = LLVM::GEPOp::create(
              rewriter, loc,
              LLVM::LLVMPointerType::get(rewriter.getContext(), loadAddrSpace),
              elemTy, loadPtr, ArrayRef<LLVM::GEPArg>{firstIndex});
          auto newLoad = LLVM::LoadOp::create(rewriter, loc, newVecTy, newPtr);
          rewriter.replaceOp(op, newLoad);
        } else {
          auto newLoad = LLVM::LoadOp::create(rewriter, loc, newVecTy, loadPtr);
          rewriter.replaceOp(op, newLoad);
        }
      } else {
        return failure();
      }
    } else {
      // No defining op (e.g. function argument): nothing to hoist/merge.
      return failure();
    }
    return success();
  }
};
 
//===----------------------------------------------------------------------===//
// Pass Definition
//===----------------------------------------------------------------------===//
 
struct ConvertXeVMToLLVMPass
    : public impl::ConvertXeVMToLLVMPassBase<ConvertXeVMToLLVMPass> {
  using Base::Base;
 
  void getDependentDialects(DialectRegistry &registry) const override {
    registry.insert<LLVM::LLVMDialect, XeVMDialect>();
  }
 
  void runOnOperation() override {
    ConversionTarget target(getContext());
    RewritePatternSet patterns(&getContext());
    populateXeVMToLLVMConversionPatterns(target, patterns);
    if (failed(applyPartialConversion(getOperation(), target,
                                      std::move(patterns))))
      signalPassFailure();
 
    // Apply in-dialect lowerings to handle illegal vectors
    {
      RewritePatternSet vectorPatterns(&getContext());
      vectorPatterns.add<HandleVectorExtractPattern>(&getContext());
      GreedyRewriteConfig config{};
      // folding can remove ops with temporary attributes used to
      // represent LLVM metadata, so disable it here.
      // Effectively just this single pattern is applied without any
      // op folding patterns from dialects.
      config.enableFolding(false);
      // config.setMaxIterations(GreedyRewriteConfig::kNoLimit);
      // config.setMaxNumRewrites(GreedyRewriteConfig::kNoLimit);
      (void)applyPatternsGreedily(getOperation(), std::move(vectorPatterns),
                                  config);
    }
  }
};
} // namespace
 
//===----------------------------------------------------------------------===//
// Pattern Population
//===----------------------------------------------------------------------===//
 
void ::mlir::populateXeVMToLLVMConversionPatterns(ConversionTarget &target,
                                                  RewritePatternSet &patterns) {
  // some LLVM operations need to be converted.
  target.addDynamicallyLegalDialect<LLVM::LLVMDialect>([](Operation *op) {
    // llvm alloca op with addrspace 3 for OpenCL (Workgroup) is not handled
    // properly by SPIRV backend. It needs to be rewritten as a sequence with
    // llvm global.
    if (isa<LLVM::AllocaOp>(op)) {
      LLVM::AllocaOp aOp = cast<LLVM::AllocaOp>(op);
      LLVM::LLVMPointerType pTy = cast<LLVM::LLVMPointerType>(aOp.getType());
      auto addrSpace = pTy.getAddressSpace();
      return addrSpace != 3;
    }
    // cache_control attribute should be converted.
    return !op->hasDiscardableAttr("cache_control");
  });
  target.addIllegalDialect<XeVMDialect>();
  patterns.add<LoadStorePrefetchToOCLPattern<BlockLoad2dOp>,
               LoadStorePrefetchToOCLPattern<BlockStore2dOp>,
               LoadStorePrefetchToOCLPattern<BlockPrefetch2dOp>,
               MMAToOCLPattern, MemfenceToOCLPattern, PrefetchToOCLPattern,
               LLVMLoadStoreToOCLPattern<LLVM::LoadOp>,
               LLVMLoadStoreToOCLPattern<LLVM::StoreOp>,
               BlockLoadStore1DToOCLPattern<BlockLoadOp>,
               BlockLoadStore1DToOCLPattern<BlockStoreOp>,
               LaunchConfigOpToOCLPattern<WorkitemIdXOp>,
               LaunchConfigOpToOCLPattern<WorkitemIdYOp>,
               LaunchConfigOpToOCLPattern<WorkitemIdZOp>,
               LaunchConfigOpToOCLPattern<WorkgroupDimXOp>,
               LaunchConfigOpToOCLPattern<WorkgroupDimYOp>,
               LaunchConfigOpToOCLPattern<WorkgroupDimZOp>,
               LaunchConfigOpToOCLPattern<WorkgroupIdXOp>,
               LaunchConfigOpToOCLPattern<WorkgroupIdYOp>,
               LaunchConfigOpToOCLPattern<WorkgroupIdZOp>,
               LaunchConfigOpToOCLPattern<GridDimXOp>,
               LaunchConfigOpToOCLPattern<GridDimYOp>,
               LaunchConfigOpToOCLPattern<GridDimZOp>,
               SubgroupOpWorkitemOpToOCLPattern<LaneIdOp>,
               SubgroupOpWorkitemOpToOCLPattern<SubgroupIdOp>,
               SubgroupOpWorkitemOpToOCLPattern<SubgroupSizeOp>,
               TruncfToOCLPattern, ExtfToOCLPattern, MMAMxToOCLPattern,
               BitcastShuffleToGenISAPattern, AllocaToGlobalPattern>(
      patterns.getContext());
}