[PATCH] D74144: [OPENMP50]Add basic support for array-shaping operation.

[Chi Chun Chen via Phabricator via cfe-commits]

cchen added a comment.
Herald added subscribers: sstefan1, yaxunl.

@ABataev, the below test is extracted from Sollve test suite and Clang now emit:

  test.c:17:35: error: subscripted value is not an array or pointer
      #pragma omp target update to( (([N][N])foo)[1:M] )
                                    ^~~~~~~~~~~~~
  test.c:17:5: error: expected at least one 'to' clause or 'from' clause specified to '#pragma omp target update'
      #pragma omp target update to( (([N][N])foo)[1:M] )

This error message came from the `ActOnOMPArraySectionExpr` which is called inside `ParsePostfixExpressionSuffix`. The issue is that the base expression in `ActOnOMPArraySectionExpr` looks like:

  ParenExpr 0x122859be0 '<OpenMP array shaping type>' lvalue
  `-OMPArrayShapingExpr 0x122859b98 '<OpenMP array shaping type>' lvalue
    |-IntegerLiteral 0x122859b38 'int' 5
    |-IntegerLiteral 0x122859b58 'int' 5
    `-DeclRefExpr 0x122859b78 'int *' lvalue Var 0x1228599d0 'foo' 'int *'

which is not a base that we would expect in an array section expr. I've tried relaxing the base type check in `ActOnOMPArraySectionExpr` but not sure it's the way to go. (or should I just extract the DeclReExpr from ArrayShapingExpr before calling `ActOnOMPArraySectionExpr`?)

  #define N 5
  #define M 3
  
  int main(void) {
      int tmp[N][N];
      for(int i=0; i<N; i++)
          for(int j=0; j<N; j++)
              tmp[i][j] = N*i + j;
  
      int *foo = &tmp[0][0];
  
      // This compiles just fine
      //#pragma omp target update to( ([N][N])foo )
  
      // This is rejected by the compiler
      #pragma omp target update to( (([N][N])foo)[1:M] )
  }


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D74144/new/

https://reviews.llvm.org/D74144