[HLSL] inout/out ABI for array parameters

[llvm-beanz]

Basic inout and out parameter support is landed, however it doesn't currently work with ArrayParameterType arguments.

The following code should compile successfully:

void increment(inout int Arr[10]) {
  for (int I = 0; I < 10; I++)
    Arr[0] += 2;
}

export int call() {
  int A[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
  increment(A);
  return A[0];
}

[llvm-beanz]

Context: Array parameters are treated as a non-decaying array types. The current [in]out support incorrectly translates the parameter's base type to a restrict reference, which results in arrays being treated as arrays of references, instead of a reference to a non-decaying array.

We need to fix that and ensure that the code generation correctly handles the temporary values.

[spall]

looking at this

[damyanp]

Blocked on #109043.

[llvmbot]

@llvm/issue-subscribers-clang-codegen

Author: Chris B (llvm-beanz)

Basic `inout` and `out` parameter support is landed, however it doesn't currently work with `ArrayParameterType` arguments.

The following code should compile successfully:

void increment(inout int Arr[10]) {
  for (int I = 0; I < 10; I++)
    Arr[0] += 2;
}

export int call() {
  int A[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
  increment(A);
  return A[0];
}

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Chris B (llvm-beanz)

Basic `inout` and `out` parameter support is landed, however it doesn't currently work with `ArrayParameterType` arguments.

The following code should compile successfully:

void increment(inout int Arr[10]) {
  for (int I = 0; I < 10; I++)
    Arr[0] += 2;
}

export int call() {
  int A[10] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
  increment(A);
  return A[0];
}