Drop CA_RISCV_ENABLED CMake option.

The CA_RISCV_ENABLED option was provided because we simultaneously want
to enable all available Mux targets by default, and disable the RISC-V
Mux target by default. This is confusing when CA_RISCV_ENABLED and
CA_MUX_TARGETS_TO_ENABLE are mismatched: it causes the RISC-V Mux target
to be disabled when either variable disables it, even when the other
variable suggests that it should be enabled. Drop CA_RISCV_ENABLED and
rely entirely on CA_MUX_TARGETS_TO_ENABLE instead.

For consistency, make the same change to CA_MUX_COMPILERS_TO_ENABLE.

For both CA_MUX_TARGETS_TO_ENABLE and CA_MUX_COMPILERS_TO_ENABLE, change
the default to "host": we expect builds that rely on other targets or
other compilers to already explicitly specify the desired target and
compiler.

Author: hvdijk

.github/actions/do_build_ock/action.yml

@@ -55,9 +55,6 @@ inputs:
   hal_refsi_thread_mode:
     description: 'HAL Refsi Thread Mode e.g. WI or WG, default ""'
     default: ""
-  riscv_enabled:
-    description: "Enable riscv target (default OFF)"
-    default: OFF
   build_dir:
     description: "Directory to be used for building"
     default: build
@@ -155,7 +152,6 @@ runs:
               -DHAL_DESCRIPTION=${{ inputs.hal_description }}
               -DHAL_REFSI_SOC=${{ inputs.hal_refsi_soc }}
               -DHAL_REFSI_THREAD_MODE=${{ inputs.hal_refsi_thread_mode }}
-              -DCA_RISCV_ENABLED=${{ inputs.riscv_enabled }}
               -DCA_CL_ENABLE_RVV_SCALABLE_VECZ_CHECK=${{ inputs.enable_rvv_scalable_vecz_check }}
               -DCA_CL_ENABLE_RVV_SCALABLE_VP_VECZ_CHECK=${{ inputs.enable_rvv_scalable_vp_vecz_check }}
               -DCA_CL_ENABLE_UNITCL_EXPENSIVE_CHECK=${{ inputs.enable_unitcl_expensive }}

.github/actions/do_build_ock/do_build_m1/action.yml

@@ -20,7 +20,6 @@ runs:
         mux_targets_enable: riscv
         mux_compilers_enable: refsi_m1
         external_compiler_dirs: "${{ github.workspace }}/examples/refsi/refsi_m1/compiler/refsi_m1"
-        riscv_enabled: ON
         enable_rvv_scalable_vecz_check: ON
         enable_rvv_scalable_vp_vecz_check: ON
         extra_flags: ${{ inputs.extra_flags }}

.github/workflows/run_pr_tests.yml

@@ -245,7 +245,6 @@ jobs:
         build_targets: check-ock-UnitCL-group-vecz
         mux_targets_enable: riscv
         mux_compilers_enable: riscv
-        riscv_enabled: ON
         enable_rvv_scalable_vecz_check: ON
         enable_rvv_scalable_vp_vecz_check: ON
         use_linker: gold
@@ -321,7 +320,6 @@ jobs:
         build_targets: check-ock
         mux_targets_enable: riscv
         mux_compilers_enable: riscv
-        riscv_enabled: ON
         disable_unitcl_vecz_checks: ON
         enable_rvv_scalable_vecz_check: ON
         enable_rvv_scalable_vp_vecz_check: ON
@@ -441,7 +439,6 @@ jobs:
         mux_targets_enable: riscv
         external_compiler_dirs: ${{ github.workspace }}/examples/refsi/refsi_g1_wi/compiler/refsi_g1_wi
         mux_compilers_enable: refsi_g1_wi
-        riscv_enabled: ON
         disable_unitcl_vecz_checks: ON
         enable_rvv_scalable_vecz_check: ON
         enable_rvv_scalable_vp_vecz_check: ON

CHANGELOG.md

@@ -6,6 +6,10 @@ 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.
+* Mux now enables only the "host" compiler and target by default. Non-host
+  builds will need to specify the compiler and target explicitly. The
+  `CA_RISCV_ENABLED` variable which served as an extra gate for the "riscv"
+  target no longer has any effect.
 
 ## Version 4.0.0
 

CMakeLists.txt

@@ -112,11 +112,11 @@ endif()
 ca_option(CA_ENABLE_DOCUMENTATION BOOL
   "Enable documentation generation" ON)
 ca_option(CA_MUX_TARGETS_TO_ENABLE STRING
-  "Semi-colon separated list of ComputeMux targets to enable, empty enables all" "")
+  "Semi-colon separated list of ComputeMux targets to enable, empty enables all" "host")
 ca_option(CA_EXTERNAL_MUX_TARGET_DIRS STRING
   "Semi-colon separated list of external ComputeMux target source directories" "")
 ca_option(CA_MUX_COMPILERS_TO_ENABLE STRING
-  "Semi-colon separated list of ComputeMux compilers to enable, empty enables all" "")
+  "Semi-colon separated list of ComputeMux compilers to enable, empty enables all" "host")
 ca_option(CA_EXTERNAL_MUX_COMPILER_DIRS STRING
   "Semi-colon separated list of external ComputeMux compiler source directories" "")
 ca_immutable_option(CA_RUNTIME_COMPILER_ENABLED BOOL

README.md

@@ -71,7 +71,6 @@ The available targets in the current implementation are based on Codeplay's refe
 ```sh
 cmake -GNinja \
    -Bbuild-riscv \
-   -DCA_RISCV_ENABLED=ON \
    -DCA_MUX_TARGETS_TO_ENABLE="riscv" \
    -DCA_LLVM_INSTALL_DIR=$LLVMInstall \
    -DCA_ENABLE_HOST_IMAGE_SUPPORT=OFF \

doc/modules/mux/bumping-the-spec.rst

@@ -11,9 +11,8 @@ Bumping the ComputeMux Specification Version
    a. Note that as long as the version number is in the 0.X.Y stage it is very
       unlikely that you will be updating the major number.
 3. Configure CMake, making sure that all ComputeMux targets are enabled. This
-   includes ``host`` which is enabled by default, the ``stub`` target which is
-   enabled with the ``CA_STUB_ENABLED``, and the RISC-V target which is enabled
-   with the ``CA_RISCV_ENABLED`` cmake option.
+   includes ``host`` which is enabled by default, and the ``stub`` and ``riscv``
+   targets.
 4. Build the ``mux-api-generate`` target e.g., ``ninja mux-api-generate``.
 5. Update ``doc/modules/mux/changes.rst``. The previous step will have
    generated an empty entry for the latest version.

doc/modules/riscv.rst

@@ -125,7 +125,6 @@ Currently recommended build options include:
 .. code-block:: console
 
  $ cmake -GNinja \
-   -DCA_RISCV_ENABLED=ON \
    -DCA_MUX_TARGETS_TO_ENABLE="riscv" \
    -DCA_LLVM_INSTALL_DIR=<llvm_install_dir>/llvm_install \
    -DCA_ENABLE_HOST_IMAGE_SUPPORT=OFF \
@@ -138,7 +137,6 @@ target has additional features. This is done by adding to the build options:
 .. code-block:: console
 
  $ cmake -GNinja \
-   -DCA_RISCV_ENABLED=ON \
    -DCA_MUX_TARGETS_TO_ENABLE="riscv" \
    -DCA_LLVM_INSTALL_DIR=<llvm_install_dir>/llvm_install \
    -DCA_ENABLE_HOST_IMAGE_SUPPORT=OFF \

examples/hal_cpu_remote_server/README.md

@@ -51,7 +51,6 @@ The client can built in-tree (for risc-v) as follows:
 ```
   cmake -Bbuild_client -GNinja \
     -DCA_MUX_TARGETS_TO_ENABLE="riscv" \
-    -DCA_RISCV_ENABLED=ON \
     -DCA_ENABLE_API=cl \
     -DCA_LLVM_INSTALL_DIR=<path_to_llvm_install> \
     -DCA_CL_ENABLE_ICD_LOADER=ON  \

modules/mux/targets/riscv/CMakeLists.txt

@@ -14,11 +14,6 @@
 #
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-ca_option(CA_RISCV_ENABLED BOOL "Enable RISC-V mux target" OFF)
-if(NOT ${CA_RISCV_ENABLED})
-  return()
-endif()
-
 ca_option(CA_HAL_NAME STRING "Name of the HAL library to link with" refsi)
 
 # Ensure that HAL targets are processed before the riscv target.