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Classes | Public Types | Public Member Functions | Static Protected Member Functions | List of all members
Function Struct Referenceabstract

The base/abstract representation of an AX function. Derived classes must implement the Function::types call to describe their signature. More...

#include <openvdb_ax/codegen/FunctionTypes.h>

Inherited by CFunctionBase, and IRFunctionBase.

Public Types

enum  SignatureMatch { None = 0, Size, Implicit, Explicit }
 The result type from calls to Function::match. More...
 
using Ptr = std::shared_ptr< Function >
 

Public Member Functions

 Function (const size_t size, const std::string &symbol)
 
virtual ~Function ()=default
 
virtual llvm::Type * types (std::vector< llvm::Type * > &, llvm::LLVMContext &) const =0
 Populate a vector of llvm::Types which describe this function signature. This method is used by Function::create, Function::print and Function::match. More...
 
virtual llvm::Function * create (llvm::LLVMContext &C, llvm::Module *M=nullptr) const
 Converts and creates this AX function into a llvm Function. More...
 
llvm::Function * create (llvm::Module &M) const
 Convenience method which always uses the provided module to find the function or insert it if necessary. More...
 
llvm::Function * get (const llvm::Module &M) const
 Convenience method for calling M.getFunction(symbol). Returns a nullptr if the function has not yet been created or if it is embedded IR. More...
 
virtual llvm::Value * call (const std::vector< llvm::Value * > &args, llvm::IRBuilder<> &B, const bool cast=false) const
 Uses the IRBuilder to create a call to this function with the given arguments, creating the function and inserting it into the IRBuilder's Module if necessary (through Function::create). Returns the result of the function call which can be a nullptr if the function is a non-sret void call. More...
 
virtual SignatureMatch match (const std::vector< llvm::Type * > &inputs, llvm::LLVMContext &C) const
 The base implementation for determining how a vector of llvm arguments translates to this functions signature. Returns an enum which represents the available mapping. More...
 
size_t size () const
 The number of arguments that this function has. More...
 
const char * symbol () const
 The function symbol name. More...
 
const char * argName (const size_t idx) const
 Returns the descriptive name of the given argument index. More...
 
virtual void print (llvm::LLVMContext &C, std::ostream &os, const char *name=nullptr, const bool axTypes=true) const
 Print this function's signature to the provided ostream. More...
 
bool hasParamAttribute (const size_t i, const llvm::Attribute::AttrKind &kind) const
 Builder methods. More...
 
void setArgumentNames (std::vector< const char * > names)
 
const std::vector< const char * > & dependencies () const
 
void setDependencies (std::vector< const char * > deps)
 
void setFnAttributes (const std::vector< llvm::Attribute::AttrKind > &in)
 
void setRetAttributes (const std::vector< llvm::Attribute::AttrKind > &in)
 
void setParamAttributes (const size_t i, const std::vector< llvm::Attribute::AttrKind > &in)
 

Static Protected Member Functions

static void cast (std::vector< llvm::Value * > &args, const std::vector< llvm::Type * > &types, llvm::IRBuilder<> &B)
 Cast the provided arguments to the given type as supported by implicit casting of function types. If the types already match OR if a cast cannot be performed, nothing is done to the argument. More...
 

Detailed Description

The base/abstract representation of an AX function. Derived classes must implement the Function::types call to describe their signature.

Member Typedef Documentation

using Ptr = std::shared_ptr<Function>

Member Enumeration Documentation

The result type from calls to Function::match.

Enumerator
None 
Size 
Implicit 
Explicit 

Constructor & Destructor Documentation

Function ( const size_t  size,
const std::string &  symbol 
)
inline
virtual ~Function ( )
virtualdefault

Member Function Documentation

const char* argName ( const size_t  idx) const
inline

Returns the descriptive name of the given argument index.

If the index is greater than the number of arguments, an empty string is returned.

Parameters
idxThe index of the argument
virtual llvm::Value* call ( const std::vector< llvm::Value * > &  args,
llvm::IRBuilder<> &  B,
const bool  cast = false 
) const
virtual

Uses the IRBuilder to create a call to this function with the given arguments, creating the function and inserting it into the IRBuilder's Module if necessary (through Function::create). Returns the result of the function call which can be a nullptr if the function is a non-sret void call.

Note
The IRBuilder must have a valid llvm Module/Function/Block attached
If the number of provided arguments do not match the size of the current function, invalid IR will be generated.
If the provided argument types do not match the current function and cast is false, invalid IR will be generated. Additionally, invalid IR will be generated if cast is true but no valid cast exists for a given argument.
When casting arguments, the readonly flags of the function are not checked (unlike Function::match). Casting an argument will cause a new copy of the argument to be created and passed to the function. These new values do not propagate back any changes to the original argument. Separate functions for all writable argument types must be created.
Parameters
argsThe llvm Value arguments to call this function with
BThe llvm IRBuilder
castWhether to allow implicit casting of arguments

Reimplemented in IRFunctionBase, CFunction< SignatureT >, SRetFunction< SignatureT, CFunction< SignatureT > >, and SRetFunction< SignatureT, IRFunction< SignatureT > >.

static void cast ( std::vector< llvm::Value * > &  args,
const std::vector< llvm::Type * > &  types,
llvm::IRBuilder<> &  B 
)
staticprotected

Cast the provided arguments to the given type as supported by implicit casting of function types. If the types already match OR if a cast cannot be performed, nothing is done to the argument.

virtual llvm::Function* create ( llvm::LLVMContext &  C,
llvm::Module *  M = nullptr 
) const
virtual

Converts and creates this AX function into a llvm Function.

This method uses the result from Function::types() to construct a llvm::FunctionType and a subsequent a llvm::Function. Any parameter, return or function attributes are also added to the function. If a module is provided, the module if first checked to see if the function already exists. If it does, it is immediately returned. If the function doesn't exist in the module, its prototype is created and also inserted into the end of the modules function list. If no module is provided, the function is left detached and must be added to a valid Module to be callable.

Warning
If a module is not provided, the caller takes ownership of the returned function and is responsible for deallocating it.
Note
The body of the function is left to derived classes to implement. As you need a Module to generate the prototype/body, this function serves two purposes. The first is to return the detached function signature if only a context is provided. The second is to ensure the function prototype and body (if required) is inserted into the module prior to returning.
It is possible to end up with function symbol collisions if you do not have unique function symbols in your module
Parameters
CThe LLVM Context
MThe Module to write the function to

Reimplemented in IRFunctionBase.

llvm::Function* create ( llvm::Module &  M) const
inline

Convenience method which always uses the provided module to find the function or insert it if necessary.

Parameters
MThe llvm::Module to use
const std::vector<const char*>& dependencies ( ) const
inline
llvm::Function* get ( const llvm::Module &  M) const

Convenience method for calling M.getFunction(symbol). Returns a nullptr if the function has not yet been created or if it is embedded IR.

Parameters
MThe llvm::Module to use
bool hasParamAttribute ( const size_t  i,
const llvm::Attribute::AttrKind &  kind 
) const
inline

Builder methods.

virtual SignatureMatch match ( const std::vector< llvm::Type * > &  inputs,
llvm::LLVMContext &  C 
) const
virtual

The base implementation for determining how a vector of llvm arguments translates to this functions signature. Returns an enum which represents the available mapping.

This method calls types() to figure out the function signature, then compares each argument type to the type in the input vector. If the types match exactly, an Explicit match is found. If the sizes of the inputs and signature differ, no match is found and None is returned. If however, the sizes match and there exists a valid implicit cast from the input type to the signature type for every input, an Implicit match is returned. Finally, if the sizes match but there is no implicit cast mapping, Size is returned. i8 -> i32 : Implicit i32 -> i32 : Explicit str -> i32 : Size (i32,i32) -> i32 : None

Note
Due to the way CFunctionSRet is implemented, the LLVM Context must be provided in case we have a zero arg function signature with a SRET.
Parameters
inputsThe input types
CThe LLVM Context

Reimplemented in SRetFunction< SignatureT, CFunction< SignatureT > >, and SRetFunction< SignatureT, IRFunction< SignatureT > >.

virtual void print ( llvm::LLVMContext &  C,
std::ostream &  os,
const char *  name = nullptr,
const bool  axTypes = true 
) const
virtual

Print this function's signature to the provided ostream.

This is intended to return a descriptive front end user string rather than the function's IR representation. This function is virtual so that derived classes can customize how they present frontend information.

See also
printSignature
Parameters
CThe llvm context
osThe ostream to print to
nameThe name to insert into the description.
axTypesWhether to print llvm IR or AX Types.

Reimplemented in SRetFunction< SignatureT, CFunction< SignatureT > >, and SRetFunction< SignatureT, IRFunction< SignatureT > >.

void setArgumentNames ( std::vector< const char * >  names)
inline
void setDependencies ( std::vector< const char * >  deps)
inline
void setFnAttributes ( const std::vector< llvm::Attribute::AttrKind > &  in)
inline
void setParamAttributes ( const size_t  i,
const std::vector< llvm::Attribute::AttrKind > &  in 
)
inline
void setRetAttributes ( const std::vector< llvm::Attribute::AttrKind > &  in)
inline
size_t size ( ) const
inline

The number of arguments that this function has.

const char* symbol ( ) const
inline

The function symbol name.

This will be used as its identifier in IR and must be unique.

virtual llvm::Type* types ( std::vector< llvm::Type * > &  ,
llvm::LLVMContext &   
) const
pure virtual

Populate a vector of llvm::Types which describe this function signature. This method is used by Function::create, Function::print and Function::match.

Implemented in IRFunction< SignatureT >, and CFunction< SignatureT >.