Making it easier to work with shaders https://git.yummers.dev/slang.git/atom?h=master 2017-12-21T01:35:10+00:00 2017-12-21T01:35:10+00:00 Tim Foley tfoleyNV@users.noreply.github.com 2017-12-21T01:35:10+00:00 urn:sha1:6f681279d99e72e717bb2b91763b80e570ae725b * IR: fixes for subscript accessors Fixes #320 This is a bunch of fixes for handling of `__subscript` operations on builtin types (notably `RWStructuredBuffer` and `StructuredBuffer` at this point). - Automatically add a `GetterDecl` to any subscript decalratio was declithout any accessors. This avoids hitting a null- dereference in the emit logic. - Add a notion of a `RefAccessor` (declared with `ref`) as a peer to getters and setters. The idea is that a `ref` accessor returns a pointer to the element data, so that it can be used for both getting and setting values. This is closer to the behavior of `RWStructuredBuffer` element access in HLSL. - Fixes for dealing with "access chains" where there might be a combination of a subscript (where the is a `get` and `set` but no `ref`) and member access, so that we have to read the base value into a temp, modify it, and then write it back. - This logic is still a bit of a mess, so we will eventually want to take a more consistent pass over this to deal with how we "materialize" values for setters. - Update `RWStructuredBuffer` to have a `ref` accessor, and then fix up the IR tests to handle the new opcode that I added for it. - Note: I didn't handle this as an intrinsic simply because the `tests/ir/*` tests aren't really set up to handle builtins with ugly mangled names. * Fixup: type error in VM for buffer element ref I was using the result type of the op as the element type for computing the element address, but the result type is a pointer to the real element type. This caused test failures on 64-bit platforms, where the stride of the buffer in the `ir/factorial` test needs to be 4. The fix is to assume the result type is a pointer, and extract the pointed-to type out of that.