Currently Clang use int32 to represent sampler_t, which have been a source of issue for some backends, because in some backends sampler_t cannot be represented by int32. They have to depend on kernel argument metadata and use IPA to find the sampler arguments and global variables and transform them to target specific sampler type.
This patch uses opaque pointer type opencl.sampler_t* for sampler_t. For each use of file-scope sampler variable, it generates a function call of __translate_sampler_initializer. For each initialization of function-scope sampler variable, it generates a function call of __translate_sampler_initializer.
Each builtin library can implement its own __translate_sampler_initializer(). Since the real sampler type tends to be architecture dependent, allowing it to be initialized by a library function simplifies backend design. A typical implementation of __translate_sampler_initializer could be a table lookup of real sampler literal values. Since its argument is always a literal, the returned pointer is known at compile time and easily optimized to finally become some literal values directly put into image read instructions.
This patch is partially based on Alexey Sotkin's work in Khronos Clang (3d4eec6162).
Differential Revision: https://reviews.llvm.org/D21567
llvm-svn: 277024
- Changes diagnostics for Blocks to be implicitly
const qualified OpenCL v2.0 s6.12.5.
- Added and unified diagnostics of some OpenCL special types:
blocks, images, samplers, pipes. These types are intended for use
with the OpenCL builtin functions only and, therefore, most regular
uses are not allowed including assignments, arithmetic operations,
pointer dereferencing, etc.
Review: http://reviews.llvm.org/D21989
llvm-svn: 275061
Applying the following restrictions for block types in OpenCL (v2.0 s6.12.5):
- __block storage class is disallowed
- every block declaration must be const qualified and initialized
- a block can't be used as a return type of a function
- a blocks can't be used to declare a structure or union field
- extern speficier is disallowed
Corrected image and sampler types diagnostics with struct and unions.
Review: http://reviews.llvm.org/D16928
llvm-svn: 262616