If in source CUDA file main header (cuda_runtime.h or cuda.h) is not presented, corresponding HIP main header (hip_runtime.h) should be explicitly included in output hipified file.
[Algorithm]
1. If #pragma once is presented, HIP main header should be placed just after it;
2. Otherwise if any other (not CUDA main) header is presented, HIP main header should be placed just before it;
3. Otherwise HIP main header should be placed in the beginning of output file.
P.S.
There might be one more situation when #ifndef #define ... #endif guard for the entire file is presented (make sense for *.h, *.hpp, *.cuh files). In this case HIP main include should be placed just after such #ifdef, or after #pragma once, if it is also presented. This situation will be handled in a separate change.
// hipified to #include<hip/hip_runtime.h>
#include<cuda.h> // 1st cuda main include (Driver API)
// to eliminate
#include<cuda_runtime.h> // 2nd cuda main include (Runtime API)
HIP has one header hip_runtime.h for both CUDA APIs, thus second cuda main include directive is eliminated entirely.
Much pretty. Very wow
This gives users all the usual power when it comes to manipulating
clang diagnostics. People can pass -Werror can have hipify fail if
it doesn't completely translate a file, for example. Much nicer
than reinventing the wheel.
Most of what hipify does is really just replacing CUDA idenitifers
with HIP ones. CUDA function calls, preprocessor macro calls,
enum references, types, etc.
This is problematic: calls/types/enum-refs require name resolution
for the AST matcher to work. This fails in the presence of code
deleted by the preprocessor, and in two-pass template compilation.
Instead, we can simply hook the lexer and have it rewrite the
identifiers for us.
This approach means identifier transformations will work correctly
regardless of where they appear (and we get to delete lots of code)
- Fixes#260
- Helps a bit with #207 - it will still fail to translate kernel
calls in preprocessor-ignored code, but everything except kerel
launches should translate correctly now, even in
preprocessor-deleted code.
Evgeny Mankov
Evgeny Mankov
Chris Kitching