NOTETwo macros can be used to define a counter variable. If you use the STATISTIC macro, then the statistic value will only be collected in a debug build if assertions [...]
The LLVM core libraries optimize the IR that your compiler creates and turn it into object code. This giant task is broken down into separate steps called passes. These passes [...]
We encapsulate the generation of debug metadata in the new CGDebugInfo class. Additionally, we place the declaration in the tinylang/CodeGen/CGDebugInfo.h header file and the definition in the tinylang/CodeGen/CGDebugInfo.cpp file.The CGDebugInfo [...]
A debugger allows a programmer to step through an application line by line. For this, the debugger needs to know which machine instructions belong to which line in the source. [...]
Again, we have to specify a source location for the variable. An instance of llvm::DILocation is a container that holds the line and column of a location associated with a [...]
To be useful, the type metadata described in the previous section needs to be associated with variables of the source program. For a global variable, this is pretty easy. The [...]
To allow source-level debugging, we have to add debug information. Support for debug information in LLVM uses debug metadata to describe the types of the source language and other static [...]
llvm::MDNode *CGTBAA::getTypeInfo(TypeDeclaration *Ty) {if (llvm::MDNode *N = MetadataCache[Ty])return N;if (auto *Pervasive =llvm::dyn_cast(Ty)) {StringRef Name = Pervasive->getName();return createScalarTypeNode(Pervasive, Name, getRoot());}if (auto *Pointer =llvm::dyn_cast(Ty)) {StringRef Name = “any pointer”;return createScalarTypeNode(Pointer, Name, getRoot());}if [...]
To support TBAA, we must add a new CGTBAA class. This class is responsible for generating the metadata nodes. Furthermore, we make the CGTBAA class a member of the CGModule [...]
To generate the IR code to catch an exception, we must add the addLandingPad() method. The generated IR extracts the type information from the exception. If it matches the C++ [...]