[OpenCL] Make global ctor init function a kernel

We need to be able to enqueue internal function that initializes
global constructors on the host side. Therefore it has to be
converted to a kernel.

This change factors out common logic for adding kernel metadata
and moves it from CodeGenFunction to CodeGenModule in order to
make it accessible for the extra use case.

Differential revision: https://reviews.llvm.org/D61488

llvm-svn: 360342

1 files changed, 206 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index a1e4511ada6..2878f9c6771 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1193,6 +1193,212 @@ void CodeGenModule::SetLLVMFunctionAttributes(GlobalDecl GD,
   F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
 }
 
+static void removeImageAccessQualifier(std::string& TyName) {
+  std::string ReadOnlyQual("__read_only");
+  std::string::size_type ReadOnlyPos = TyName.find(ReadOnlyQual);
+  if (ReadOnlyPos != std::string::npos)
+    // "+ 1" for the space after access qualifier.
+    TyName.erase(ReadOnlyPos, ReadOnlyQual.size() + 1);
+  else {
+    std::string WriteOnlyQual("__write_only");
+    std::string::size_type WriteOnlyPos = TyName.find(WriteOnlyQual);
+    if (WriteOnlyPos != std::string::npos)
+      TyName.erase(WriteOnlyPos, WriteOnlyQual.size() + 1);
+    else {
+      std::string ReadWriteQual("__read_write");
+      std::string::size_type ReadWritePos = TyName.find(ReadWriteQual);
+      if (ReadWritePos != std::string::npos)
+        TyName.erase(ReadWritePos, ReadWriteQual.size() + 1);
+    }
+  }
+}
+
+// Returns the address space id that should be produced to the
+// kernel_arg_addr_space metadata. This is always fixed to the ids
+// as specified in the SPIR 2.0 specification in order to differentiate
+// for example in clGetKernelArgInfo() implementation between the address
+// spaces with targets without unique mapping to the OpenCL address spaces
+// (basically all single AS CPUs).
+static unsigned ArgInfoAddressSpace(LangAS AS) {
+  switch (AS) {
+  case LangAS::opencl_global:   return 1;
+  case LangAS::opencl_constant: return 2;
+  case LangAS::opencl_local:    return 3;
+  case LangAS::opencl_generic:  return 4; // Not in SPIR 2.0 specs.
+  default:
+    return 0; // Assume private.
+  }
+}
+
+void CodeGenModule::GenOpenCLArgMetadata(llvm::Function *Fn,
+                                         const FunctionDecl *FD,
+                                         CodeGenFunction *CGF) {
+  assert(((FD && CGF) || (!FD && !CGF)) &&
+         "Incorrect use - FD and CGF should either be both null or not!");
+  // Create MDNodes that represent the kernel arg metadata.
+  // Each MDNode is a list in the form of "key", N number of values which is
+  // the same number of values as their are kernel arguments.
+
+  const PrintingPolicy &Policy = Context.getPrintingPolicy();
+
+  // MDNode for the kernel argument address space qualifiers.
+  SmallVector<llvm::Metadata *, 8> addressQuals;
+
+  // MDNode for the kernel argument access qualifiers (images only).
+  SmallVector<llvm::Metadata *, 8> accessQuals;
+
+  // MDNode for the kernel argument type names.
+  SmallVector<llvm::Metadata *, 8> argTypeNames;
+
+  // MDNode for the kernel argument base type names.
+  SmallVector<llvm::Metadata *, 8> argBaseTypeNames;
+
+  // MDNode for the kernel argument type qualifiers.
+  SmallVector<llvm::Metadata *, 8> argTypeQuals;
+
+  // MDNode for the kernel argument names.
+  SmallVector<llvm::Metadata *, 8> argNames;
+
+  if (FD && CGF)
+    for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) {
+      const ParmVarDecl *parm = FD->getParamDecl(i);
+      QualType ty = parm->getType();
+      std::string typeQuals;
+
+      if (ty->isPointerType()) {
+        QualType pointeeTy = ty->getPointeeType();
+
+        // Get address qualifier.
+        addressQuals.push_back(
+            llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(
+                ArgInfoAddressSpace(pointeeTy.getAddressSpace()))));
+
+        // Get argument type name.
+        std::string typeName =
+            pointeeTy.getUnqualifiedType().getAsString(Policy) + "*";
+
+        // Turn "unsigned type" to "utype"
+        std::string::size_type pos = typeName.find("unsigned");
+        if (pointeeTy.isCanonical() && pos != std::string::npos)
+          typeName.erase(pos + 1, 8);
+
+        argTypeNames.push_back(llvm::MDString::get(VMContext, typeName));
+
+        std::string baseTypeName =
+            pointeeTy.getUnqualifiedType().getCanonicalType().getAsString(
+                Policy) +
+            "*";
+
+        // Turn "unsigned type" to "utype"
+        pos = baseTypeName.find("unsigned");
+        if (pos != std::string::npos)
+          baseTypeName.erase(pos + 1, 8);
+
+        argBaseTypeNames.push_back(
+            llvm::MDString::get(VMContext, baseTypeName));
+
+        // Get argument type qualifiers:
+        if (ty.isRestrictQualified())
+          typeQuals = "restrict";
+        if (pointeeTy.isConstQualified() ||
+            (pointeeTy.getAddressSpace() == LangAS::opencl_constant))
+          typeQuals += typeQuals.empty() ? "const" : " const";
+        if (pointeeTy.isVolatileQualified())
+          typeQuals += typeQuals.empty() ? "volatile" : " volatile";
+      } else {
+        uint32_t AddrSpc = 0;
+        bool isPipe = ty->isPipeType();
+        if (ty->isImageType() || isPipe)
+          AddrSpc = ArgInfoAddressSpace(LangAS::opencl_global);
+
+        addressQuals.push_back(
+            llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(AddrSpc)));
+
+        // Get argument type name.
+        std::string typeName;
+        if (isPipe)
+          typeName = ty.getCanonicalType()
+                         ->getAs<PipeType>()
+                         ->getElementType()
+                         .getAsString(Policy);
+        else
+          typeName = ty.getUnqualifiedType().getAsString(Policy);
+
+        // Turn "unsigned type" to "utype"
+        std::string::size_type pos = typeName.find("unsigned");
+        if (ty.isCanonical() && pos != std::string::npos)
+          typeName.erase(pos + 1, 8);
+
+        std::string baseTypeName;
+        if (isPipe)
+          baseTypeName = ty.getCanonicalType()
+                             ->getAs<PipeType>()
+                             ->getElementType()
+                             .getCanonicalType()
+                             .getAsString(Policy);
+        else
+          baseTypeName =
+              ty.getUnqualifiedType().getCanonicalType().getAsString(Policy);
+
+        // Remove access qualifiers on images
+        // (as they are inseparable from type in clang implementation,
+        // but OpenCL spec provides a special query to get access qualifier
+        // via clGetKernelArgInfo with CL_KERNEL_ARG_ACCESS_QUALIFIER):
+        if (ty->isImageType()) {
+          removeImageAccessQualifier(typeName);
+          removeImageAccessQualifier(baseTypeName);
+        }
+
+        argTypeNames.push_back(llvm::MDString::get(VMContext, typeName));
+
+        // Turn "unsigned type" to "utype"
+        pos = baseTypeName.find("unsigned");
+        if (pos != std::string::npos)
+          baseTypeName.erase(pos + 1, 8);
+
+        argBaseTypeNames.push_back(
+            llvm::MDString::get(VMContext, baseTypeName));
+
+        if (isPipe)
+          typeQuals = "pipe";
+      }
+
+      argTypeQuals.push_back(llvm::MDString::get(VMContext, typeQuals));
+
+      // Get image and pipe access qualifier:
+      if (ty->isImageType() || ty->isPipeType()) {
+        const Decl *PDecl = parm;
+        if (auto *TD = dyn_cast<TypedefType>(ty))
+          PDecl = TD->getDecl();
+        const OpenCLAccessAttr *A = PDecl->getAttr<OpenCLAccessAttr>();
+        if (A && A->isWriteOnly())
+          accessQuals.push_back(llvm::MDString::get(VMContext, "write_only"));
+        else if (A && A->isReadWrite())
+          accessQuals.push_back(llvm::MDString::get(VMContext, "read_write"));
+        else
+          accessQuals.push_back(llvm::MDString::get(VMContext, "read_only"));
+      } else
+        accessQuals.push_back(llvm::MDString::get(VMContext, "none"));
+
+      // Get argument name.
+      argNames.push_back(llvm::MDString::get(VMContext, parm->getName()));
+    }
+
+  Fn->setMetadata("kernel_arg_addr_space",
+                  llvm::MDNode::get(VMContext, addressQuals));
+  Fn->setMetadata("kernel_arg_access_qual",
+                  llvm::MDNode::get(VMContext, accessQuals));
+  Fn->setMetadata("kernel_arg_type",
+                  llvm::MDNode::get(VMContext, argTypeNames));
+  Fn->setMetadata("kernel_arg_base_type",
+                  llvm::MDNode::get(VMContext, argBaseTypeNames));
+  Fn->setMetadata("kernel_arg_type_qual",
+                  llvm::MDNode::get(VMContext, argTypeQuals));
+  if (getCodeGenOpts().EmitOpenCLArgMetadata)
+    Fn->setMetadata("kernel_arg_name",
+                    llvm::MDNode::get(VMContext, argNames));
+}
+
 /// Determines whether the language options require us to model
 /// unwind exceptions.  We treat -fexceptions as mandating this
 /// except under the fragile ObjC ABI with only ObjC exceptions