-Make more use of InstructionBuilder instruction helper methods
-Use MakeUnique<>() rather than new
-Add InstrumentPass::GenReadFunctionCall() which optimizes function
calls in a loop with constant arguments and no side effects.
This is a prepatory change for future work on the instrumentation
code which will add more generated functions.
Avoid using OpConstantNull with types that do not allow it.
Update existing tests for slight changes in code generation.
Add new tests based on the Vulkan Validation layer test case
that exposed this problem.
Add name annotations to the generated instrumentation code to
make it easier to understand. Example spirv-cross output:
vec4 _140;
if (0u < inst_bindless_direct_read_4(0u, 0u, 1u, uint(_19)))
{
_140 = texture(textures[nonuniformEXT(_19)], inUV);
}
else
{
inst_bindless_stream_write_4(50u, 1u, uint(_19), 0u);
_140 = vec4(0.0);
}
