1//===----- CGOpenCLRuntime.cpp - Interface to OpenCL Runtimes -------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This provides an abstract class for OpenCL code generation.  Concrete
10// subclasses of this implement code generation for specific OpenCL
11// runtime libraries.
12//
13//===----------------------------------------------------------------------===//
14
15#include "CGOpenCLRuntime.h"
16#include "CodeGenFunction.h"
17#include "TargetInfo.h"
18#include "clang/CodeGen/ConstantInitBuilder.h"
19#include "llvm/IR/DerivedTypes.h"
20#include "llvm/IR/GlobalValue.h"
21#include <assert.h>
22
23using namespace clang;
24using namespace CodeGen;
25
26CGOpenCLRuntime::~CGOpenCLRuntime() {}
27
28void CGOpenCLRuntime::EmitWorkGroupLocalVarDecl(CodeGenFunction &CGF,
29                                                const VarDecl &D) {
30  return CGF.EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
31}
32
33llvm::Type *CGOpenCLRuntime::convertOpenCLSpecificType(const Type *T) {
34  assert(T->isOpenCLSpecificType() &&
35         "Not an OpenCL specific type!");
36
37  llvm::LLVMContext& Ctx = CGM.getLLVMContext();
38  uint32_t AddrSpc = CGM.getContext().getTargetAddressSpace(
39      CGM.getContext().getOpenCLTypeAddrSpace(T));
40  switch (cast<BuiltinType>(T)->getKind()) {
41  default:
42    llvm_unreachable("Unexpected opencl builtin type!");
43    return nullptr;
44#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
45  case BuiltinType::Id: \
46    return llvm::PointerType::get( \
47        llvm::StructType::create(Ctx, "opencl." #ImgType "_" #Suffix "_t"), \
48        AddrSpc);
49#include "clang/Basic/OpenCLImageTypes.def"
50  case BuiltinType::OCLSampler:
51    return getSamplerType(T);
52  case BuiltinType::OCLEvent:
53    return llvm::PointerType::get(
54        llvm::StructType::create(Ctx, "opencl.event_t"), AddrSpc);
55  case BuiltinType::OCLClkEvent:
56    return llvm::PointerType::get(
57        llvm::StructType::create(Ctx, "opencl.clk_event_t"), AddrSpc);
58  case BuiltinType::OCLQueue:
59    return llvm::PointerType::get(
60        llvm::StructType::create(Ctx, "opencl.queue_t"), AddrSpc);
61  case BuiltinType::OCLReserveID:
62    return llvm::PointerType::get(
63        llvm::StructType::create(Ctx, "opencl.reserve_id_t"), AddrSpc);
64#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
65  case BuiltinType::Id: \
66    return llvm::PointerType::get( \
67        llvm::StructType::create(Ctx, "opencl." #ExtType), AddrSpc);
68#include "clang/Basic/OpenCLExtensionTypes.def"
69  }
70}
71
72llvm::Type *CGOpenCLRuntime::getPipeType(const PipeType *T) {
73  if (T->isReadOnly())
74    return getPipeType(T, "opencl.pipe_ro_t", PipeROTy);
75  else
76    return getPipeType(T, "opencl.pipe_wo_t", PipeWOTy);
77}
78
79llvm::Type *CGOpenCLRuntime::getPipeType(const PipeType *T, StringRef Name,
80                                         llvm::Type *&PipeTy) {
81  if (!PipeTy)
82    PipeTy = llvm::PointerType::get(llvm::StructType::create(
83      CGM.getLLVMContext(), Name),
84      CGM.getContext().getTargetAddressSpace(
85          CGM.getContext().getOpenCLTypeAddrSpace(T)));
86  return PipeTy;
87}
88
89llvm::PointerType *CGOpenCLRuntime::getSamplerType(const Type *T) {
90  if (!SamplerTy)
91    SamplerTy = llvm::PointerType::get(llvm::StructType::create(
92      CGM.getLLVMContext(), "opencl.sampler_t"),
93      CGM.getContext().getTargetAddressSpace(
94          CGM.getContext().getOpenCLTypeAddrSpace(T)));
95  return SamplerTy;
96}
97
98llvm::Value *CGOpenCLRuntime::getPipeElemSize(const Expr *PipeArg) {
99  const PipeType *PipeTy = PipeArg->getType()->castAs<PipeType>();
100  // The type of the last (implicit) argument to be passed.
101  llvm::Type *Int32Ty = llvm::IntegerType::getInt32Ty(CGM.getLLVMContext());
102  unsigned TypeSize = CGM.getContext()
103                          .getTypeSizeInChars(PipeTy->getElementType())
104                          .getQuantity();
105  return llvm::ConstantInt::get(Int32Ty, TypeSize, false);
106}
107
108llvm::Value *CGOpenCLRuntime::getPipeElemAlign(const Expr *PipeArg) {
109  const PipeType *PipeTy = PipeArg->getType()->castAs<PipeType>();
110  // The type of the last (implicit) argument to be passed.
111  llvm::Type *Int32Ty = llvm::IntegerType::getInt32Ty(CGM.getLLVMContext());
112  unsigned TypeSize = CGM.getContext()
113                          .getTypeAlignInChars(PipeTy->getElementType())
114                          .getQuantity();
115  return llvm::ConstantInt::get(Int32Ty, TypeSize, false);
116}
117
118llvm::PointerType *CGOpenCLRuntime::getGenericVoidPointerType() {
119  assert(CGM.getLangOpts().OpenCL);
120  return llvm::IntegerType::getInt8PtrTy(
121      CGM.getLLVMContext(),
122      CGM.getContext().getTargetAddressSpace(LangAS::opencl_generic));
123}
124
125// Get the block literal from an expression derived from the block expression.
126// OpenCL v2.0 s6.12.5:
127// Block variable declarations are implicitly qualified with const. Therefore
128// all block variables must be initialized at declaration time and may not be
129// reassigned.
130static const BlockExpr *getBlockExpr(const Expr *E) {
131  const Expr *Prev = nullptr; // to make sure we do not stuck in infinite loop.
132  while(!isa<BlockExpr>(E) && E != Prev) {
133    Prev = E;
134    E = E->IgnoreCasts();
135    if (auto DR = dyn_cast<DeclRefExpr>(E)) {
136      E = cast<VarDecl>(DR->getDecl())->getInit();
137    }
138  }
139  return cast<BlockExpr>(E);
140}
141
142/// Record emitted llvm invoke function and llvm block literal for the
143/// corresponding block expression.
144void CGOpenCLRuntime::recordBlockInfo(const BlockExpr *E,
145                                      llvm::Function *InvokeF,
146                                      llvm::Value *Block) {
147  assert(EnqueuedBlockMap.find(E) == EnqueuedBlockMap.end() &&
148         "Block expression emitted twice");
149  assert(isa<llvm::Function>(InvokeF) && "Invalid invoke function");
150  assert(Block->getType()->isPointerTy() && "Invalid block literal type");
151  EnqueuedBlockMap[E].InvokeFunc = InvokeF;
152  EnqueuedBlockMap[E].BlockArg = Block;
153  EnqueuedBlockMap[E].Kernel = nullptr;
154}
155
156llvm::Function *CGOpenCLRuntime::getInvokeFunction(const Expr *E) {
157  return EnqueuedBlockMap[getBlockExpr(E)].InvokeFunc;
158}
159
160CGOpenCLRuntime::EnqueuedBlockInfo
161CGOpenCLRuntime::emitOpenCLEnqueuedBlock(CodeGenFunction &CGF, const Expr *E) {
162  CGF.EmitScalarExpr(E);
163
164  // The block literal may be assigned to a const variable. Chasing down
165  // to get the block literal.
166  const BlockExpr *Block = getBlockExpr(E);
167
168  assert(EnqueuedBlockMap.find(Block) != EnqueuedBlockMap.end() &&
169         "Block expression not emitted");
170
171  // Do not emit the block wrapper again if it has been emitted.
172  if (EnqueuedBlockMap[Block].Kernel) {
173    return EnqueuedBlockMap[Block];
174  }
175
176  auto *F = CGF.getTargetHooks().createEnqueuedBlockKernel(
177      CGF, EnqueuedBlockMap[Block].InvokeFunc,
178      EnqueuedBlockMap[Block].BlockArg->stripPointerCasts());
179
180  // The common part of the post-processing of the kernel goes here.
181  F->addFnAttr(llvm::Attribute::NoUnwind);
182  F->setCallingConv(
183      CGF.getTypes().ClangCallConvToLLVMCallConv(CallingConv::CC_OpenCLKernel));
184  EnqueuedBlockMap[Block].Kernel = F;
185  return EnqueuedBlockMap[Block];
186}
187