[mux] Remove degenerate subgroup support.

CHANGELOG.md

@@ -1,4 +1,11 @@
-# ComputeAorta Changes
+# oneAPI Construction Kit Changes
+
+## TBD
+
+Upgrade guidance:
+
+* Support for degenerate subgroups has been removed. No in-tree target or
+  template was using this, but custom targets may need to be updated.
 
 ## Version 4.0.0
 

doc/modules/mux/changes.rst

@@ -11,6 +11,11 @@ version increases mean backward compatible bug fixes have been applied.
    Versions prior to 1.0.0 may contain breaking changes in minor
    versions as the API is still under development.
 
+0.81.0
+------
+
+* Removed ``mux-degenerate-subgroups``.
+
 0.80.0
 ------
 

doc/specifications/mux-compiler-spec.rst

@@ -1,7 +1,7 @@
 ComputeMux Compiler Specification
 =================================
 
-   This is version 0.80.0 of the specification.
+   This is version 0.81.0 of the specification.
 
 ComputeMux is Codeplay’s proprietary API for executing compute workloads across
 heterogeneous devices. ComputeMux is an extremely lightweight,
@@ -1432,9 +1432,6 @@ different stages of the pipeline:
        by the use of known mux sub-group builtins). If a pass introduces the
        explicit use of sub-groups to a function, it should remove this
        attribute.
-   * - ``"mux-degenerate-subgroups"``
-     - Marks the function has using degenerate sub-groups (i.e. one sub-group
-       for the entire local work-group).
 
 ``mux-kernel`` attribute
 ~~~~~~~~~~~~~~~~~~~~~~~~

doc/specifications/mux-runtime-spec.rst

@@ -1,7 +1,7 @@
 ComputeMux Runtime Specification
 ================================
 
-   This is version 0.80.0 of the specification.
+   This is version 0.81.0 of the specification.
 
 ComputeMux is Codeplay’s proprietary API for executing compute workloads across
 heterogeneous devices. ComputeMux is an extremely lightweight,

modules/compiler/compiler_pipeline/CMakeLists.txt

@@ -27,7 +27,6 @@ add_ca_library(compiler-pipeline STATIC
   ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/compute_local_memory_usage_pass.h
   ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/define_mux_builtins_pass.h
   ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/define_mux_dma_pass.h
-  ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/degenerate_sub_group_pass.h
   ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/device_info.h
   ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/dma.h
   ${CMAKE_CURRENT_SOURCE_DIR}/include/compiler/utils/encode_builtin_range_metadata_pass.h
@@ -79,7 +78,6 @@ add_ca_library(compiler-pipeline STATIC
   ${CMAKE_CURRENT_SOURCE_DIR}/source/compute_local_memory_usage_pass.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/source/define_mux_builtins_pass.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/source/define_mux_dma_pass.cpp
-  ${CMAKE_CURRENT_SOURCE_DIR}/source/degenerate_sub_group_pass.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/source/dma.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/source/encode_builtin_range_metadata_pass.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/source/encode_kernel_metadata_pass.cpp

modules/compiler/compiler_pipeline/include/compiler/utils/attributes.h

@@ -162,16 +162,6 @@ void setBarrierSchedule(llvm::CallInst &CI, BarrierSchedule Sched);
 /// @return the execution schedule for this barrier
 BarrierSchedule getBarrierSchedule(const llvm::CallInst &CI);
 
-/// @brief Marks a kernel's subgroups as degenerate
-///
-/// @param[in] F Function in which to encode the information.
-void setHasDegenerateSubgroups(llvm::Function &F);
-
-/// @brief Returns whether the kernel has degenerate subgroups.
-///
-/// @param[in] F Function to check.
-bool hasDegenerateSubgroups(const llvm::Function &F);
-
 /// @brief Marks a function as not explicitly using subgroups
 ///
 /// May be set even with unresolved external functions, assuming those don't

modules/compiler/compiler_pipeline/source/attributes.cpp

@@ -186,18 +186,6 @@ BarrierSchedule getBarrierSchedule(const CallInst &CI) {
   return BarrierSchedule::Unordered;
 }
 
-static constexpr const char *MuxDegenerateSubgroupsAttrName =
-    "mux-degenerate-subgroups";
-
-void setHasDegenerateSubgroups(Function &F) {
-  F.addFnAttr(MuxDegenerateSubgroupsAttrName);
-}
-
-bool hasDegenerateSubgroups(const Function &F) {
-  const Attribute Attr = F.getFnAttribute(MuxDegenerateSubgroupsAttrName);
-  return Attr.isValid();
-}
-
 static constexpr const char *MuxNoSubgroupsAttrName = "mux-no-subgroups";
 
 void setHasNoExplicitSubgroups(Function &F) {