TVM runtime backend API. More...

#include <tvm/runtime/c_runtime_api.h>

Include dependency graph for c_backend_api.h:

This graph shows which files directly or indirectly include this file:

Classes
struct	TVMParallelGroupEnv
	Environment for TVM parallel task. More...

Typedefs
typedef int(*	TVMBackendPackedCFunc) (TVMValue args, int type_codes, int num_args, TVMValue out_ret_value, int out_ret_tcode, void *resource_handle)
	Signature for backend functions exported as DLL. More...

typedef int(*	FTVMParallelLambda) (int task_id, TVMParallelGroupEnv penv, void cdata)
	The callback function to execute a parallel lambda. More...

Functions
int	TVMBackendGetFuncFromEnv (void mod_node, const char func_name, TVMFunctionHandle *out)
	Backend function for modules to get function from its environment mod_node (its imports and global function). The user do should not call TVMFuncFree on func. More...

int	TVMBackendRegisterSystemLibSymbol (const char name, void ptr)
	Backend function to register system-wide library symbol. More...

void *	TVMBackendAllocWorkspace (int device_type, int device_id, uint64_t nbytes, int dtype_code_hint, int dtype_bits_hint)
	Backend function to allocate temporal workspace. More...

int	TVMBackendFreeWorkspace (int device_type, int device_id, void *ptr)
	Backend function to free temporal workspace. More...

int	TVMBackendRegisterEnvCAPI (const char name, void ptr)
	Backend function to register execution environment(e.g. python) specific C APIs. More...

int	TVMBackendParallelLaunch (FTVMParallelLambda flambda, void *cdata, int num_task)
	Backend function for running parallel jobs. More...

int	TVMBackendParallelBarrier (int task_id, TVMParallelGroupEnv *penv)
	BSP barrrier between parallel threads. More...

int	TVMBackendRunOnce (void *handle, int(f)(void ), void cdata, int nbytes)
	Simple static initialization function. Run f once and set handle to be not null. This function is mainly used for test purpose. More...

Detailed Description

TVM runtime backend API.

The functions defined in this header are intended to be used by compiled tvm operators, usually user do not need to use these function directly.

Typedef Documentation

◆ FTVMParallelLambda

typedef int(* FTVMParallelLambda) (int task_id, TVMParallelGroupEnv *penv, void *cdata)

The callback function to execute a parallel lambda.

Parameters

task_id	the task id of the function.
penv	The parallel environment backs the execution.
cdata	The supporting closure data.

◆ TVMBackendPackedCFunc

typedef int(* TVMBackendPackedCFunc) (TVMValue *args, int *type_codes, int num_args, TVMValue *out_ret_value, int *out_ret_tcode, void *resource_handle)

Signature for backend functions exported as DLL.

Parameters

args	The arguments
type_codes	The type codes of the arguments
num_args	Number of arguments.
out_ret_value	The output value of the return value.
out_ret_tcode	The output type code of the return value.
resource_handle	Pointer to associated resource.

Returns: 0 if success, -1 if failure happens, set error via TVMAPISetLastError.

Function Documentation

◆ TVMBackendAllocWorkspace()

void* TVMBackendAllocWorkspace	(	int	device_type,
		int	device_id,
		uint64_t	nbytes,
		int	dtype_code_hint,
		int	dtype_bits_hint
	)

Backend function to allocate temporal workspace.

Note: The result allocated space is ensured to be aligned to kTempAllocaAlignment.

Parameters

nbytes	The size of the space requested.
device_type	The device type which the space will be allocated.
device_id	The device id which the space will be allocated.
dtype_code_hint	The type code of the array elements. Only used in certain backends such as OpenGL.
dtype_bits_hint	The type bits of the array elements. Only used in certain backends such as OpenGL.

Returns: nullptr when error is thrown, a valid ptr if success

◆ TVMBackendFreeWorkspace()

int TVMBackendFreeWorkspace	(	int	device_type,
		int	device_id,
		void *	ptr
	)

Backend function to free temporal workspace.

Parameters

ptr	The result allocated space pointer.
device_type	The device type which the space will be allocated.
device_id	The device id which the space will be allocated.

Returns: 0 when no error is thrown, -1 when failure happens

See also: TVMBackendAllocWorkspace

◆ TVMBackendGetFuncFromEnv()

int TVMBackendGetFuncFromEnv	(	void *	mod_node,
		const char *	func_name,
		TVMFunctionHandle *	out
	)

Backend function for modules to get function from its environment mod_node (its imports and global function). The user do should not call TVMFuncFree on func.

Parameters

mod_node	The module handle.
func_name	The name of the function.
out	The result function.

Returns: 0 when no error is thrown, -1 when failure happens

◆ TVMBackendParallelBarrier()

int TVMBackendParallelBarrier	(	int	task_id,
		TVMParallelGroupEnv *	penv
	)

BSP barrrier between parallel threads.

Parameters

task_id	the task id of the function.
penv	The parallel environment backs the execution.

Returns: 0 when no error is thrown, -1 when failure happens

◆ TVMBackendParallelLaunch()

int TVMBackendParallelLaunch	(	FTVMParallelLambda	flambda,
		void *	cdata,
		int	num_task
	)

Backend function for running parallel jobs.

Parameters

flambda	The parallel function to be launched.
cdata	The closure data.
num_task	Number of tasks to launch, can be 0, means launch with all available threads.

Returns: 0 when no error is thrown, -1 when failure happens

Examples: /workspace/include/tvm/runtime/threading_backend.h.

◆ TVMBackendRegisterEnvCAPI()

int TVMBackendRegisterEnvCAPI	(	const char *	name,
		void *	ptr
	)

Backend function to register execution environment(e.g. python) specific C APIs.

Note: We only register the C API function when absolutely necessary (e.g. when signal handler cannot trap back into python). In most cases we should use the PackedFunc FFI.

Parameters

name	The name of the symbol
ptr	The symbol address.

Returns: 0 when no error is thrown, -1 when failure happens

◆ TVMBackendRegisterSystemLibSymbol()

int TVMBackendRegisterSystemLibSymbol	(	const char *	name,
		void *	ptr
	)

Backend function to register system-wide library symbol.

Parameters

name	The name of the symbol
ptr	The symbol address.

Returns: 0 when no error is thrown, -1 when failure happens

◆ TVMBackendRunOnce()

int TVMBackendRunOnce	(	void **	handle,
		int()(void )	f,
		void *	cdata,
		int	nbytes
	)

Simple static initialization function. Run f once and set handle to be not null. This function is mainly used for test purpose.

Parameters

handle	A global address to indicate f
f	The function to be run
cdata	The closure data to pass to the function.
nbytes	Number of bytes in the closure data.

Returns: 0 when no error is thrown, -1 when failure happens

Classes

Typedefs

Functions

Detailed Description

Typedef Documentation

◆ FTVMParallelLambda

◆ TVMBackendPackedCFunc

Function Documentation

◆ TVMBackendAllocWorkspace()

◆ TVMBackendFreeWorkspace()

◆ TVMBackendGetFuncFromEnv()

◆ TVMBackendParallelBarrier()

◆ TVMBackendParallelLaunch()

◆ TVMBackendRegisterEnvCAPI()

◆ TVMBackendRegisterSystemLibSymbol()

◆ TVMBackendRunOnce()