A block name cannot alias with any name in its own scope,
and it cannot alias with any other "global" name.
To solve this, we need to complicate the name cache updates a little bit
where we have a "primary" namespace and "secondary" namespace.
This is required to avoid relying on complex sub-expression elimination
in compilers, and generates cleaner code.
The problem case is if a complex expression is used in an access chain,
like:
Composite comp = buffer[texture(...)];
vec4 a = comp.a + comp.b + comp.c;
Before, we did not have common subexpression tracking for
OpLoad/OpAccessChain, so we easily ended up with code like:
vec4 a = buffer[texture(...)].a + buffer[texture(...)].b + buffer[texture(...)].c;
A good compiler will optimize this, but we should not rely on it, and
forcing texture(...) to a temporary also looks better.
The solution is to add a vector "implied_expression_reads", which works
similarly to expression_dependencies. We also need an extra mechanism in
to_expression which lets us skip expression read checking and do it
later. E.g. for expr -> access chain -> load, we should only trigger
a read of expr when using the loaded expression.
This is a large refactor which splits out the SPIR-V parser from
Compiler and moves it into its more appropriately named Parser module.
The Parser is responsible for building a ParsedIR structure which is
then consumed by one or more compilers.
Compiler can take a ParsedIR by value or move reference. This should
allow for optimal case for both multiple compilations and single
compilation scenarios.
Implement this by flattening outputs and unflattening inputs explicitly.
This allows us to pass down a single struct instead of dealing with the
insanity that would be passing down each flattened member separately.
Remove stage_uniforms_var_id.
Seems to be dead code. Naked uniforms do not exist in SPIR-V for Vulkan,
which this seems to have been intended for. It was also unused elsewhere.
Two varyings (vertex outputs/fragment inputs) might have the same
location but be in different components--e.g. the compiler may have
packed what were two different varyings into a single varying vector.
Giving both varyings the same `[[user]]` attribute won't work--it may
yield unexpected results, or flat out fail to link. We could eventually
pack such varyings into a single vector, but that would require us to
handle the case where the varyings are different types--e.g. a `float`
and a `uint` packed into the same vector. For now, it seems most
prudent to give them unique `[[user]]` locations and let Apple's
compiler work out the best way to pack them.
- Do not emit set = in GLSL, even when non-zero.
- Fix warning on tautological comparison.
- Expose get_buffer_block_flags as mentioned in reflection guide.
Deal with various query functions which require dummy sampler.
In SPIR-V, separate images are used, but GLSL (even Vulkan GLSL)
requires combined sampler images ...
SPIR-V allows names to alias if they implement different stages.
Deprecate the old interface and replace it with a new one which takes
execution modes into account.
Normally, temporary declaration must dominate any use of it,
so we generally did not need to analyze the CFG for these variables,
but there is an edge case where you have an inliner doing:
do {
create_temporary;
break;
} while(0);
use_temporary;
The inside of the loop dominates the outer scope, but we cannot emit
code like this in GLSL, so make sure we hoist these temporaries outside
the "loop".
HLSL UAVs are a bit annoying because they can share block types,
so reflection becomes rather awkward. Sometimes we will need to make
some nasty fallbacks, so add a reflection interface which lets you query
post-shader compile which names was actually declared in the shader.
We don't have a mechanism to move temporaries to their appropriate
scope, and Phi behavior is weird enough that it will be a heroic effort
to not do this rather ugly codegen :(
Support Workgroup (threadgroup) variables.
Mark if SPIRConstant is used as an array length, since it cannot be specialized.
Resolve specialized array length constants.
Support passing an array to MSL function.
Support emitting GLSL array assignments in MSL via an array copy function.
Support for memory and control barriers.
Struct packing enhancements, including packing nested structs.
Enhancements to replacing illegal MSL variable and function names.
Add Compiler::get_entry_point_name_map() function to retrieve entry point renamings.
Remove CompilerGLSL::clean_func_name() as obsolete.
Fixes to types in bitcast MSL functions.
Add Variant::get_id() member function.
Add CompilerMSL::Options::msl_version option.
Add numerous MSL compute tests.
