Also added known-good mechanism to fetch latest validated spirv-tools.
Also added -Od and -Os to disable optimizer and optimize for size.
Fetching spirv-tools is optional for both glsl and hlsl. Legalization
of hlsl is done by default if spirv-opt is present at cmake time.
Optimization for glsl is currently done through the option -Os.
Legalization testing is currently only done on four existing shaders.
A separate baseLegalResults directory holds those results. All previous
testing is done with the optimizer disabled.
Remapper errors are generally fatal: there has been some unexpected situation while
parsing the SPV binary, and there is no reasonable way to carry on. The
errorHandler() function is called in this case, which by default exits, but
it is possible to submit a handler which does not. In that case the remapper would
carry on in a bad state.
This change ensures a graceful termination of the remap() function.
While a try {} catch {} construct would be the ideal and safe way to do this,
that's off limits for certain environments, so this tries to do the same thing
with explicit code, to catch all the bailout paths.
InputPatch parameters to patch constant functions were not using the
internal (temporary) variable type. That could cause validation errors
if the input patch had a mixture of builtins and user qualified members.
This uses the entry point's internal form.
There is currently a limitation: if an InputPatch is used in a PCF,
it must also have appeared in the main entry point's parameter list.
That is not a limitation of HLSL. Currently that situation is detected
and an "implemented" error results. The limitation can be addressed,
but isn't yet in the current form of the PR.
Hull shaders have an implicitly arrayed output. This is handled by creating an arrayed form of the
provided output type, and writing to the element of it indexed by InvocationID.
The implicit indirection into that array was causing some troubles when copying to a split
structure. handleAssign was able to handle simple symbol lvalues, but not an lvalue composed
of an indirection into an array.
There was some ambiguity/contradiction in this behavior, and
Khronos decided glslang should always have these outside blocks,
rather than have stage/vendor/target variations.
There were several locations in TGlslangToSpvTraverser::handleUserFunctionCall testing for
whether a fn argument should be in the lvalue or rvalue array. They must get the same
result for indexing sanity, but had slightly different logic.
They're now forced into the same test.
Changes:
(1) Allow clip/cull builtins as both input and output in the same shader stage. Previously,
not enough data was tracked to handle this.
(2) Handle the extra array dimension in GS inputs. The synthesized external variable can
now be created with the extra array dimension if needed, and the form conversion code is
able to handle it as well.
For example, both of these GS inputs would result in the same synthesized external type:
triangle in float4 clip[3] : SV_ClipDistance
triangle in float2 clip[3][2] : SV_ClipDistance
In the second case, the inner array dimension packs with the 2-vector of floats into an array[4],
which there is an array[3] of due to the triangle geometry.
While adding geometry stage support for clip/cull, it transpired that the
existing clip/cull support was not setting the type of the result of indexing
into the clup/cull variable. That's a defect independent of the geometry
support, so to simplify the geometry PR, this is addressed separately.
It doesn't appear to change the generated SPIR-V, but that's probably down to
something else tolerating a bad input.
