Hello world¶

In this example, we will write a program in hidet script to print out "hello, world".

Before we start, we need to install two python packages with the following cell to enable stdout capture.

In [1]:
%%capture
%load_ext wurlitzer
In [2]:
import hidet
from hidet.lang import printf, attr

# declare a script module, all script function inside the with-context will be added to it
with hidet.script_module() as script_module:
    
    # all functions decorated by "hidet.script" will be marked as Hidet Script function
    @hidet.script
    def main():
        # mark this function is a host side function (run on cpu)
        attr.func_kind = 'host_kernel'
        
        # print out
        printf('hello, world!\n')

# get the ir module (hidet.ir.IRModule), which is the top-level IR node
ir_module = script_module.ir_module()

print('IRModule:')
print(str(ir_module).strip())    # hidet.ir.IRModule
print()

IRModule:
def main fn()
    # func_kind: host_kernel
    printf("hello, world!\n");
In [3]:
# compile the ir module to a dynamic library and load it into a python callable
compiled_func = hidet.driver.build_ir_module(ir_module, func_name='main')
print('        Source path: "{}"'.format(compiled_func.src_path))
print('   Compiled library: "{}"'.format(compiled_func.lib_path))

        Source path: "./outs/ir_module/1ba570cf9a404d0f/source.cu"
   Compiled library: "./outs/ir_module/1ba570cf9a404d0f/lib.so"

Hidet will compile an IRModule to a dynamic library (e.g., lib.so), and dynamically load it into the python environment.

In [4]:
print('Source code:\n{}'.format(compiled_func.source(color=True)))

Source code:
#include <stdint.h>
#include <cuda_fp16.h>
#include <cuda_bf16.h>
#include <hidet/runtime/cuda_context.h>
#include <hidet/runtime/cpu_context.h>
typedef float tfloat32_t;
#define __float_to_tf32(x) (x)
extern "C" {

__host__ void hidet_main() {
  printf("hello, world!\n");
}

}
In [5]:
print('Run the compiled program:')
compiled_func()

Run the compiled program:
hello, world!