//===--- SPIRVCallLowering.cpp - Call lowering ------------------*- C++ -*-===//
//
// 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 the lowering of LLVM calls to machine code calls for
// GlobalISel.
//
//===----------------------------------------------------------------------===//
#include "SPIRVCallLowering.h"
#include "MCTargetDesc/SPIRVBaseInfo.h"
#include "SPIRV.h"
#include "SPIRVBuiltins.h"
#include "SPIRVGlobalRegistry.h"
#include "SPIRVISelLowering.h"
#include "SPIRVMetadata.h"
#include "SPIRVRegisterInfo.h"
#include "SPIRVSubtarget.h"
#include "SPIRVUtils.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/IntrinsicsSPIRV.h"
#include "llvm/Support/ModRef.h"
using namespace llvm;
SPIRVCallLowering::SPIRVCallLowering(const SPIRVTargetLowering &TLI,
SPIRVGlobalRegistry *GR)
: CallLowering(&TLI), GR(GR) {}
bool SPIRVCallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
const Value *Val, ArrayRef<Register> VRegs,
FunctionLoweringInfo &FLI,
Register SwiftErrorVReg) const {
// Maybe run postponed production of types for function pointers
if (IndirectCalls.size() > 0) {
produceIndirectPtrTypes(MIRBuilder);
IndirectCalls.clear();
}
// Currently all return types should use a single register.
// TODO: handle the case of multiple registers.
if (VRegs.size() > 1)
return false;
if (Val) {
const auto &STI = MIRBuilder.getMF().getSubtarget();
return MIRBuilder.buildInstr(SPIRV::OpReturnValue)
.addUse(VRegs[0])
.constrainAllUses(MIRBuilder.getTII(), *STI.getRegisterInfo(),
*STI.getRegBankInfo());
}
MIRBuilder.buildInstr(SPIRV::OpReturn);
return true;
}
// Based on the LLVM function attributes, get a SPIR-V FunctionControl.
static uint32_t getFunctionControl(const Function &F) {
MemoryEffects MemEffects = F.getMemoryEffects();
uint32_t FuncControl = static_cast<uint32_t>(SPIRV::FunctionControl::None);
if (F.hasFnAttribute(Attribute::AttrKind::NoInline))
FuncControl |= static_cast<uint32_t>(SPIRV::FunctionControl::DontInline);
else if (F.hasFnAttribute(Attribute::AttrKind::AlwaysInline))
FuncControl |= static_cast<uint32_t>(SPIRV::FunctionControl::Inline);
if (MemEffects.doesNotAccessMemory())
FuncControl |= static_cast<uint32_t>(SPIRV::FunctionControl::Pure);
else if (MemEffects.onlyReadsMemory())
FuncControl |= static_cast<uint32_t>(SPIRV::FunctionControl::Const);
return FuncControl;
}
static ConstantInt *getConstInt(MDNode *MD, unsigned NumOp) {
if (MD->getNumOperands() > NumOp) {
auto *CMeta = dyn_cast<ConstantAsMetadata>(MD->getOperand(NumOp));
if (CMeta)
return dyn_cast<ConstantInt>(CMeta->getValue());
}
return nullptr;
}
// If the function has pointer arguments, we are forced to re-create this
// function type from the very beginning, changing PointerType by
// TypedPointerType for each pointer argument. Otherwise, the same `Type*`
// potentially corresponds to different SPIR-V function type, effectively
// invalidating logic behind global registry and duplicates tracker.
static FunctionType *
fixFunctionTypeIfPtrArgs(SPIRVGlobalRegistry *GR, const Function &F,
FunctionType *FTy, const SPIRVType *SRetTy,
const SmallVector<SPIRVType *, 4> &SArgTys) {
if (F.getParent()->getNamedMetadata("spv.cloned_funcs"))
return FTy;
bool hasArgPtrs = false;
for (auto &Arg : F.args()) {
// check if it's an instance of a non-typed PointerType
if (Arg.getType()->isPointerTy()) {
hasArgPtrs = true;
break;
}
}
if (!hasArgPtrs) {
Type *RetTy = FTy->getReturnType();
// check if it's an instance of a non-typed PointerType
if (!RetTy->isPointerTy())
return FTy;
}
// re-create function type, using TypedPointerType instead of PointerType to
// properly trace argument types
const Type *RetTy = GR->getTypeForSPIRVType(SRetTy);
SmallVector<Type *, 4> ArgTys;
for (auto SArgTy : SArgTys)
ArgTys.push_back(const_cast<Type *>(GR->getTypeForSPIRVType(SArgTy)));
return FunctionType::get(const_cast<Type *>(RetTy), ArgTys, false);
}
// This code restores function args/retvalue types for composite cases
// because the final types should still be aggregate whereas they're i32
// during the translation to cope with aggregate flattening etc.
static FunctionType *getOriginalFunctionType(const Function &F) {
auto *NamedMD = F.getParent()->getNamedMetadata("spv.cloned_funcs");
if (NamedMD == nullptr)
return F.getFunctionType();
Type *RetTy = F.getFunctionType()->getReturnType();
SmallVector<Type *, 4> ArgTypes;
for (auto &Arg : F.args())
ArgTypes.push_back(Arg.getType());
auto ThisFuncMDIt =
std::find_if(NamedMD->op_begin(), NamedMD->op_end(), [&F](MDNode *N) {
return isa<MDString>(N->getOperand(0)) &&
cast<MDString>(N->getOperand(0))->getString() == F.getName();
});
// TODO: probably one function can have numerous type mutations,
// so we should support this.
if (ThisFuncMDIt != NamedMD->op_end()) {
auto *ThisFuncMD = *ThisFuncMDIt;
MDNode *MD = dyn_cast<MDNode>(ThisFuncMD->getOperand(1));
assert(MD && "MDNode operand is expected");
ConstantInt *Const = getConstInt(MD, 0);
if (Const) {
auto *CMeta = dyn_cast<ConstantAsMetadata>(MD->getOperand(1));
assert(CMeta && "ConstantAsMetadata operand is expected");
assert(Const->getSExtValue() >= -1);
// Currently -1 indicates return value, greater values mean
// argument numbers.
if (Const->getSExtValue() == -1)
RetTy = CMeta->getType();
else
ArgTypes[Const->getSExtValue()] = CMeta->getType();
}
}
return FunctionType::get(RetTy, ArgTypes, F.isVarArg());
}
static SPIRV::AccessQualifier::AccessQualifier
getArgAccessQual(const Function &F, unsigned ArgIdx) {
if (F.getCallingConv() != CallingConv::SPIR_KERNEL)
return SPIRV::AccessQualifier::ReadWrite;
MDString *ArgAttribute = getOCLKernelArgAccessQual(F, ArgIdx);
if (!ArgAttribute)
return SPIRV::AccessQualifier::ReadWrite;
if (ArgAttribute->getString() == "read_only")
return SPIRV::AccessQualifier::ReadOnly;
if (ArgAttribute->getString() == "write_only")
return SPIRV::AccessQualifier::WriteOnly;
return SPIRV::AccessQualifier::ReadWrite;
}
static std::vector<SPIRV::Decoration::Decoration>
getKernelArgTypeQual(const Function &F, unsigned ArgIdx) {
MDString *ArgAttribute = getOCLKernelArgTypeQual(F, ArgIdx);
if (ArgAttribute && ArgAttribute->getString() == "volatile")
return {SPIRV::Decoration::Volatile};
return {};
}
static SPIRVType *getArgSPIRVType(const Function &F, unsigned ArgIdx,
SPIRVGlobalRegistry *GR,
MachineIRBuilder &MIRBuilder,
const SPIRVSubtarget &ST) {
// Read argument's access qualifier from metadata or default.
SPIRV::AccessQualifier::AccessQualifier ArgAccessQual =
getArgAccessQual(F, ArgIdx);
Type *OriginalArgType = getOriginalFunctionType(F)->getParamType(ArgIdx);
// If OriginalArgType is non-pointer, use the OriginalArgType (the type cannot
// be legally reassigned later).
if (!isPointerTy(OriginalArgType))
return GR->getOrCreateSPIRVType(OriginalArgType, MIRBuilder, ArgAccessQual);
Argument *Arg = F.getArg(ArgIdx);
Type *ArgType = Arg->getType();
if (isTypedPointerTy(ArgType)) {
SPIRVType *ElementType = GR->getOrCreateSPIRVType(
cast<TypedPointerType>(ArgType)->getElementType(), MIRBuilder);
return GR->getOrCreateSPIRVPointerType(
ElementType, MIRBuilder,
addressSpaceToStorageClass(getPointerAddressSpace(ArgType), ST));
}
// In case OriginalArgType is of untyped pointer type, there are three
// possibilities:
// 1) This is a pointer of an LLVM IR element type, passed byval/byref.
// 2) This is an OpenCL/SPIR-V builtin type if there is spv_assign_type
// intrinsic assigning a TargetExtType.
// 3) This is a pointer, try to retrieve pointer element type from a
// spv_assign_ptr_type intrinsic or otherwise use default pointer element
// type.
if (hasPointeeTypeAttr(Arg)) {
SPIRVType *ElementType =
GR->getOrCreateSPIRVType(getPointeeTypeByAttr(Arg), MIRBuilder);
return GR->getOrCreateSPIRVPointerType(
ElementType, MIRBuilder,
addressSpaceToStorageClass(getPointerAddressSpace(ArgType), ST));
}
for (auto User : Arg->users()) {
auto *II = dyn_cast<IntrinsicInst>(User);
// Check if this is spv_assign_type assigning OpenCL/SPIR-V builtin type.
if (II && II->getIntrinsicID() == Intrinsic::spv_assign_type) {
MetadataAsValue *VMD = cast<MetadataAsValue>(II->getOperand(1));
Type *BuiltinType =
cast<ConstantAsMetadata>(VMD->getMetadata())->getType();
assert(BuiltinType->isTargetExtTy() && "Expected TargetExtType");
return GR->getOrCreateSPIRVType(BuiltinType, MIRBuilder, ArgAccessQual);
}
// Check if this is spv_assign_ptr_type assigning pointer element type.
if (!II || II->getIntrinsicID() != Intrinsic::spv_assign_ptr_type)
continue;
MetadataAsValue *VMD = cast<MetadataAsValue>(II->getOperand(1));
Type *ElementTy =
toTypedPointer(cast<ConstantAsMetadata>(VMD->getMetadata())->getType());
SPIRVType *ElementType = GR->getOrCreateSPIRVType(ElementTy, MIRBuilder);
return GR->getOrCreateSPIRVPointerType(
ElementType, MIRBuilder,
addressSpaceToStorageClass(
cast<ConstantInt>(II->getOperand(2))->getZExtValue(), ST));
}
// Replace PointerType with TypedPointerType to be able to map SPIR-V types to
// LLVM types in a consistent manner
return GR->getOrCreateSPIRVType(toTypedPointer(OriginalArgType), MIRBuilder,
ArgAccessQual);
}
static SPIRV::ExecutionModel::ExecutionModel
getExecutionModel(const SPIRVSubtarget &STI, const Function &F) {
if (STI.isOpenCLEnv())
return SPIRV::ExecutionModel::Kernel;
auto attribute = F.getFnAttribute("hlsl.shader");
if (!attribute.isValid()) {
report_fatal_error(
"This entry point lacks mandatory hlsl.shader attribute.");
}
const auto value = attribute.getValueAsString();
if (value == "compute")
return SPIRV::ExecutionModel::GLCompute;
report_fatal_error("This HLSL entry point is not supported by this backend.");
}
bool SPIRVCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
const Function &F,
ArrayRef<ArrayRef<Register>> VRegs,
FunctionLoweringInfo &FLI) const {
assert(GR && "Must initialize the SPIRV type registry before lowering args.");
GR->setCurrentFunc(MIRBuilder.getMF());
// Get access to information about available extensions
const SPIRVSubtarget *ST =
static_cast<const SPIRVSubtarget *>(&MIRBuilder.getMF().getSubtarget());
// Assign types and names to all args, and store their types for later.
SmallVector<SPIRVType *, 4> ArgTypeVRegs;
if (VRegs.size() > 0) {
unsigned i = 0;
for (const auto &Arg : F.args()) {
// Currently formal args should use single registers.
// TODO: handle the case of multiple registers.
if (VRegs[i].size() > 1)
return false;
auto *SpirvTy = getArgSPIRVType(F, i, GR, MIRBuilder, *ST);
GR->assignSPIRVTypeToVReg(SpirvTy, VRegs[i][0], MIRBuilder.getMF());
ArgTypeVRegs.push_back(SpirvTy);
if (Arg.hasName())
buildOpName(VRegs[i][0], Arg.getName(), MIRBuilder);
if (isPointerTy(Arg.getType())) {
auto DerefBytes = static_cast<unsigned>(Arg.getDereferenceableBytes());
if (DerefBytes != 0)
buildOpDecorate(VRegs[i][0], MIRBuilder,
SPIRV::Decoration::MaxByteOffset, {DerefBytes});
}
if (Arg.hasAttribute(Attribute::Alignment)) {
auto Alignment = static_cast<unsigned>(
Arg.getAttribute(Attribute::Alignment).getValueAsInt());
buildOpDecorate(VRegs[i][0], MIRBuilder, SPIRV::Decoration::Alignment,
{Alignment});
}
if (Arg.hasAttribute(Attribute::ReadOnly)) {
auto Attr =
static_cast<unsigned>(SPIRV::FunctionParameterAttribute::NoWrite);
buildOpDecorate(VRegs[i][0], MIRBuilder,
SPIRV::Decoration::FuncParamAttr, {Attr});
}
if (Arg.hasAttribute(Attribute::ZExt)) {
auto Attr =
static_cast<unsigned>(SPIRV::FunctionParameterAttribute::Zext);
buildOpDecorate(VRegs[i][0], MIRBuilder,
SPIRV::Decoration::FuncParamAttr, {Attr});
}
if (Arg.hasAttribute(Attribute::NoAlias)) {
auto Attr =
static_cast<unsigned>(SPIRV::FunctionParameterAttribute::NoAlias);
buildOpDecorate(VRegs[i][0], MIRBuilder,
SPIRV::Decoration::FuncParamAttr, {Attr});
}
if (Arg.hasAttribute(Attribute::ByVal)) {
auto Attr =
static_cast<unsigned>(SPIRV::FunctionParameterAttribute::ByVal);
buildOpDecorate(VRegs[i][0], MIRBuilder,
SPIRV::Decoration::FuncParamAttr, {Attr});
}
if (F.getCallingConv() == CallingConv::SPIR_KERNEL) {
std::vector<SPIRV::Decoration::Decoration> ArgTypeQualDecs =
getKernelArgTypeQual(F, i);
for (SPIRV::Decoration::Decoration Decoration : ArgTypeQualDecs)
buildOpDecorate(VRegs[i][0], MIRBuilder, Decoration, {});
}
MDNode *Node = F.getMetadata("spirv.ParameterDecorations");
if (Node && i < Node->getNumOperands() &&
isa<MDNode>(Node->getOperand(i))) {
MDNode *MD = cast<MDNode>(Node->getOperand(i));
for (const MDOperand &MDOp : MD->operands()) {
MDNode *MD2 = dyn_cast<MDNode>(MDOp);
assert(MD2 && "Metadata operand is expected");
ConstantInt *Const = getConstInt(MD2, 0);
assert(Const && "MDOperand should be ConstantInt");
auto Dec =
static_cast<SPIRV::Decoration::Decoration>(Const->getZExtValue());
std::vector<uint32_t> DecVec;
for (unsigned j = 1; j < MD2->getNumOperands(); j++) {
ConstantInt *Const = getConstInt(MD2, j);
assert(Const && "MDOperand should be ConstantInt");
DecVec.push_back(static_cast<uint32_t>(Const->getZExtValue()));
}
buildOpDecorate(VRegs[i][0], MIRBuilder, Dec, DecVec);
}
}
++i;
}
}
auto MRI = MIRBuilder.getMRI();
Register FuncVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
MRI->setRegClass(FuncVReg, &SPIRV::iIDRegClass);
if (F.isDeclaration())
GR->add(&F, &MIRBuilder.getMF(), FuncVReg);
FunctionType *FTy = getOriginalFunctionType(F);
Type *FRetTy = FTy->getReturnType();
if (isUntypedPointerTy(FRetTy)) {
if (Type *FRetElemTy = GR->findDeducedElementType(&F)) {
TypedPointerType *DerivedTy = TypedPointerType::get(
toTypedPointer(FRetElemTy), getPointerAddressSpace(FRetTy));
GR->addReturnType(&F, DerivedTy);
FRetTy = DerivedTy;
}
}
SPIRVType *RetTy = GR->getOrCreateSPIRVType(FRetTy, MIRBuilder);
FTy = fixFunctionTypeIfPtrArgs(GR, F, FTy, RetTy, ArgTypeVRegs);
SPIRVType *FuncTy = GR->getOrCreateOpTypeFunctionWithArgs(
FTy, RetTy, ArgTypeVRegs, MIRBuilder);
uint32_t FuncControl = getFunctionControl(F);
// Add OpFunction instruction
MachineInstrBuilder MB = MIRBuilder.buildInstr(SPIRV::OpFunction)
.addDef(FuncVReg)
.addUse(GR->getSPIRVTypeID(RetTy))
.addImm(FuncControl)
.addUse(GR->getSPIRVTypeID(FuncTy));
GR->recordFunctionDefinition(&F, &MB.getInstr()->getOperand(0));
// Add OpFunctionParameter instructions
int i = 0;
for (const auto &Arg : F.args()) {
assert(VRegs[i].size() == 1 && "Formal arg has multiple vregs");
Register ArgReg = VRegs[i][0];
MRI->setRegClass(ArgReg, GR->getRegClass(ArgTypeVRegs[i]));
MRI->setType(ArgReg, GR->getRegType(ArgTypeVRegs[i]));
MIRBuilder.buildInstr(SPIRV::OpFunctionParameter)
.addDef(ArgReg)
.addUse(GR->getSPIRVTypeID(ArgTypeVRegs[i]));
if (F.isDeclaration())
GR->add(&Arg, &MIRBuilder.getMF(), ArgReg);
i++;
}
// Name the function.
if (F.hasName())
buildOpName(FuncVReg, F.getName(), MIRBuilder);
// Handle entry points and function linkage.
if (isEntryPoint(F)) {
const auto &STI = MIRBuilder.getMF().getSubtarget<SPIRVSubtarget>();
auto executionModel = getExecutionModel(STI, F);
auto MIB = MIRBuilder.buildInstr(SPIRV::OpEntryPoint)
.addImm(static_cast<uint32_t>(executionModel))
.addUse(FuncVReg);
addStringImm(F.getName(), MIB);
} else if (F.getLinkage() != GlobalValue::InternalLinkage &&
F.getLinkage() != GlobalValue::PrivateLinkage) {
SPIRV::LinkageType::LinkageType LnkTy =
F.isDeclaration()
? SPIRV::LinkageType::Import
: (F.getLinkage() == GlobalValue::LinkOnceODRLinkage &&
ST->canUseExtension(
SPIRV::Extension::SPV_KHR_linkonce_odr)
? SPIRV::LinkageType::LinkOnceODR
: SPIRV::LinkageType::Export);
buildOpDecorate(FuncVReg, MIRBuilder, SPIRV::Decoration::LinkageAttributes,
{static_cast<uint32_t>(LnkTy)}, F.getGlobalIdentifier());
}
// Handle function pointers decoration
bool hasFunctionPointers =
ST->canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers);
if (hasFunctionPointers) {
if (F.hasFnAttribute("referenced-indirectly")) {
assert((F.getCallingConv() != CallingConv::SPIR_KERNEL) &&
"Unexpected 'referenced-indirectly' attribute of the kernel "
"function");
buildOpDecorate(FuncVReg, MIRBuilder,
SPIRV::Decoration::ReferencedIndirectlyINTEL, {});
}
}
return true;
}
// Used to postpone producing of indirect function pointer types after all
// indirect calls info is collected
// TODO:
// - add a topological sort of IndirectCalls to ensure the best types knowledge
// - we may need to fix function formal parameter types if they are opaque
// pointers used as function pointers in these indirect calls
void SPIRVCallLowering::produceIndirectPtrTypes(
MachineIRBuilder &MIRBuilder) const {
// Create indirect call data types if any
MachineFunction &MF = MIRBuilder.getMF();
for (auto const &IC : IndirectCalls) {
SPIRVType *SpirvRetTy = GR->getOrCreateSPIRVType(IC.RetTy, MIRBuilder);
SmallVector<SPIRVType *, 4> SpirvArgTypes;
for (size_t i = 0; i < IC.ArgTys.size(); ++i) {
SPIRVType *SPIRVTy = GR->getOrCreateSPIRVType(IC.ArgTys[i], MIRBuilder);
SpirvArgTypes.push_back(SPIRVTy);
if (!GR->getSPIRVTypeForVReg(IC.ArgRegs[i]))
GR->assignSPIRVTypeToVReg(SPIRVTy, IC.ArgRegs[i], MF);
}
// SPIR-V function type:
FunctionType *FTy =
FunctionType::get(const_cast<Type *>(IC.RetTy), IC.ArgTys, false);
SPIRVType *SpirvFuncTy = GR->getOrCreateOpTypeFunctionWithArgs(
FTy, SpirvRetTy, SpirvArgTypes, MIRBuilder);
// SPIR-V pointer to function type:
SPIRVType *IndirectFuncPtrTy = GR->getOrCreateSPIRVPointerType(
SpirvFuncTy, MIRBuilder, SPIRV::StorageClass::Function);
// Correct the Callee type
GR->assignSPIRVTypeToVReg(IndirectFuncPtrTy, IC.Callee, MF);
}
}
bool SPIRVCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
CallLoweringInfo &Info) const {
// Currently call returns should have single vregs.
// TODO: handle the case of multiple registers.
if (Info.OrigRet.Regs.size() > 1)
return false;
MachineFunction &MF = MIRBuilder.getMF();
GR->setCurrentFunc(MF);
const Function *CF = nullptr;
std::string DemangledName;
const Type *OrigRetTy = Info.OrigRet.Ty;
// Emit a regular OpFunctionCall. If it's an externally declared function,
// be sure to emit its type and function declaration here. It will be hoisted
// globally later.
if (Info.Callee.isGlobal()) {
std::string FuncName = Info.Callee.getGlobal()->getName().str();
DemangledName = getOclOrSpirvBuiltinDemangledName(FuncName);
CF = dyn_cast_or_null<const Function>(Info.Callee.getGlobal());
// TODO: support constexpr casts and indirect calls.
if (CF == nullptr)
return false;
if (FunctionType *FTy = getOriginalFunctionType(*CF)) {
OrigRetTy = FTy->getReturnType();
if (isUntypedPointerTy(OrigRetTy)) {
if (auto *DerivedRetTy = GR->findReturnType(CF))
OrigRetTy = DerivedRetTy;
}
}
}
MachineRegisterInfo *MRI = MIRBuilder.getMRI();
Register ResVReg =
Info.OrigRet.Regs.empty() ? Register(0) : Info.OrigRet.Regs[0];
const auto *ST = static_cast<const SPIRVSubtarget *>(&MF.getSubtarget());
bool isFunctionDecl = CF && CF->isDeclaration();
bool canUseOpenCL = ST->canUseExtInstSet(SPIRV::InstructionSet::OpenCL_std);
bool canUseGLSL = ST->canUseExtInstSet(SPIRV::InstructionSet::GLSL_std_450);
assert(canUseGLSL != canUseOpenCL &&
"Scenario where both sets are enabled is not supported.");
if (isFunctionDecl && !DemangledName.empty() &&
(canUseGLSL || canUseOpenCL)) {
SmallVector<Register, 8> ArgVRegs;
for (auto Arg : Info.OrigArgs) {
assert(Arg.Regs.size() == 1 && "Call arg has multiple VRegs");
Register ArgReg = Arg.Regs[0];
ArgVRegs.push_back(ArgReg);
SPIRVType *SpvType = GR->getSPIRVTypeForVReg(ArgReg);
if (!SpvType) {
SpvType = GR->getOrCreateSPIRVType(Arg.Ty, MIRBuilder);
GR->assignSPIRVTypeToVReg(SpvType, ArgReg, MF);
}
if (!MRI->getRegClassOrNull(ArgReg)) {
MRI->setRegClass(ArgReg, GR->getRegClass(SpvType));
MRI->setType(ArgReg, GR->getRegType(SpvType));
}
}
auto instructionSet = canUseOpenCL ? SPIRV::InstructionSet::OpenCL_std
: SPIRV::InstructionSet::GLSL_std_450;
if (auto Res =
SPIRV::lowerBuiltin(DemangledName, instructionSet, MIRBuilder,
ResVReg, OrigRetTy, ArgVRegs, GR))
return *Res;
}
if (isFunctionDecl && !GR->find(CF, &MF).isValid()) {
// Emit the type info and forward function declaration to the first MBB
// to ensure VReg definition dependencies are valid across all MBBs.
MachineIRBuilder FirstBlockBuilder;
FirstBlockBuilder.setMF(MF);
FirstBlockBuilder.setMBB(*MF.getBlockNumbered(0));
SmallVector<ArrayRef<Register>, 8> VRegArgs;
SmallVector<SmallVector<Register, 1>, 8> ToInsert;
for (const Argument &Arg : CF->args()) {
if (MIRBuilder.getDataLayout().getTypeStoreSize(Arg.getType()).isZero())
continue; // Don't handle zero sized types.
Register Reg = MRI->createGenericVirtualRegister(LLT::scalar(64));
MRI->setRegClass(Reg, &SPIRV::iIDRegClass);
ToInsert.push_back({Reg});
VRegArgs.push_back(ToInsert.back());
}
// TODO: Reuse FunctionLoweringInfo
FunctionLoweringInfo FuncInfo;
lowerFormalArguments(FirstBlockBuilder, *CF, VRegArgs, FuncInfo);
}
unsigned CallOp;
if (Info.CB->isIndirectCall()) {
if (!ST->canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers))
report_fatal_error("An indirect call is encountered but SPIR-V without "
"extensions does not support it",
false);
// Set instruction operation according to SPV_INTEL_function_pointers
CallOp = SPIRV::OpFunctionPointerCallINTEL;
// Collect information about the indirect call to support possible
// specification of opaque ptr types of parent function's parameters
Register CalleeReg = Info.Callee.getReg();
if (CalleeReg.isValid()) {
SPIRVCallLowering::SPIRVIndirectCall IndirectCall;
IndirectCall.Callee = CalleeReg;
IndirectCall.RetTy = OrigRetTy;
for (const auto &Arg : Info.OrigArgs) {
assert(Arg.Regs.size() == 1 && "Call arg has multiple VRegs");
IndirectCall.ArgTys.push_back(Arg.Ty);
IndirectCall.ArgRegs.push_back(Arg.Regs[0]);
}
IndirectCalls.push_back(IndirectCall);
}
} else {
// Emit a regular OpFunctionCall
CallOp = SPIRV::OpFunctionCall;
}
// Make sure there's a valid return reg, even for functions returning void.
if (!ResVReg.isValid())
ResVReg = MIRBuilder.getMRI()->createVirtualRegister(&SPIRV::iIDRegClass);
SPIRVType *RetType = GR->assignTypeToVReg(OrigRetTy, ResVReg, MIRBuilder);
// Emit the call instruction and its args.
auto MIB = MIRBuilder.buildInstr(CallOp)
.addDef(ResVReg)
.addUse(GR->getSPIRVTypeID(RetType))
.add(Info.Callee);
for (const auto &Arg : Info.OrigArgs) {
// Currently call args should have single vregs.
if (Arg.Regs.size() > 1)
return false;
MIB.addUse(Arg.Regs[0]);
}
return MIB.constrainAllUses(MIRBuilder.getTII(), *ST->getRegisterInfo(),
*ST->getRegBankInfo());
}