[HLSL] Assigning array from cbuffer fails

[llvm-beanz]

Now that cbuffer values are declared in a unique address space we're seeing a failure assigning an array from a cbuffer:

cbuffer CBArrays : register(b0) {
  float c1[2];
  int4 c2[2][2];
  bool c3[2];
}

struct Arrays {
  float c1[2];
  int4 c2[2][2];
  bool c3[2];
};

RWStructuredBuffer<Arrays> Out : register(u0);

[numthreads(1,1,1)]
void main() {
  Out[0].c1 = c1;
  Out[0].c2 = c2;
  Out[0].c3 = c3;
}

Compiler Explorer

[damyanp]

Some more investigation required before we can estimate this.

We need to address this for the DML shaders.

[spall]

The assignment fails because in Sema Checking because the ToType and the FromType do not have the same Qualified Type; the FromType has an address space qualifier.
Expected solution:

• Update Sema Checking to add an LValue to RValue cast in this case.
• Update Codegen to ensure that the LValue to RValue cast loads from the address space to a temporary.
• Add tests.

[spall]

Blocked on a design discussion

[spall]

No longer blocked on a design discussion.