[OpenMP][deviceRTLs] Drop `assert` in common parts of `deviceRTLs`

[tianshilei1992]

Summary

The header assert.h needs to be included in order to use assert in the code.
When building NVPTX deviceRTLs on a CUDA free system, it requires headers from
gcc-multilib, which some systems don't have. This patch drops the use of
assert in common parts of deviceRTLs. In light of
openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.h, a code block

if (!cond)
  __builtin_trap();

is being used. The builtin will be translated to call void @llvm.trap(), and
the corresponding PTX is trap;.

[JonChesterfield]

Yep, like this.

Ptx documents an intrinsic/builtin/syscall thing for assert that we could use instead of trap. Involves creating a call to __assertfail, takes five arguments one of which is sizeof(char). This is much simpler and serves the same purpose though.

Could you delete the assert impl from amdgpu at the same time?

[tianshilei1992]

Remove useless function in amdgcn

[JonChesterfield]

openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.h

21 ↗

(On Diff #321277)

Can drop this include too

[tianshilei1992]

removed #include <assert.h>

[tianshilei1992]

openmp/libomptarget/deviceRTLs/amdgcn/src/target_impl.h

21 ↗

(On Diff #321277)

Aha, you guys also included it here 😂

openmp/libomptarget/deviceRTLs/common/debug.h

 //   WARNING(flag, str, args)      : if warning flag is on, print the warning
 //   WON(flag)                     : return true if warning flag is on
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef _OMPTARGET_NVPTX_DEBUG_H_
 #define _OMPTARGET_NVPTX_DEBUG_H_
 
 #include "common/device_environment.h"
 #include "target_interface.h"
 
 ////////////////////////////////////////////////////////////////////////////////
 // set desired level of debugging
 ////////////////////////////////////////////////////////////////////////////////
 
 #define LD_SET_NONE 0ULL /* none */
 #define LD_SET_ALL -1ULL /* all */

 }
 
 #endif
 #if OMPTARGET_NVPTX_TEST
 
 template <typename... Arguments>
 NOINLINE static void check(bool cond, const char *fmt,
                            Arguments... parameters) {
-  if (!cond)
+  if (!cond) {
     printf(fmt, (int)GetBlockIdInKernel(), (int)GetThreadIdInBlock(),
            (int)GetWarpId(), (int)GetLaneId(), parameters...);
-  assert(cond);
+    __builtin_trap();
+  }
 }
 
-NOINLINE static void check(bool cond) { assert(cond); }
+NOINLINE static void check(bool cond) {
+  if (!cond)
+    __builtin_trap();
+}
 #endif
 
 // set flags that are tested (inclusion properties)
 
 #define LD_ALL (LD_SET_ALL)
 
 #define LD_LOOP (LD_SET_LOOP | LD_SET_LOOPD)
 #define LD_LOOPD (LD_SET_LOOPD)

openmp/libomptarget/deviceRTLs/nvptx/src/target_impl.h

 //===------------ target_impl.h - NVPTX OpenMP GPU options ------- CUDA -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // Definitions of target specific functions
 //
 //===----------------------------------------------------------------------===//
 #ifndef _TARGET_IMPL_H_
 #define _TARGET_IMPL_H_
 
-#include <assert.h>
 #include <inttypes.h>
 #include <stdio.h>
 #include <stdlib.h>
 
 #include "nvptx_interface.h"
 
 #define DEVICE
 #define INLINE inline __attribute__((always_inline)) DEVICE