diff --git a/libclc/CMakeLists.txt b/libclc/CMakeLists.txt
index 3f8445833695..334faa1a0266 100644
--- a/libclc/CMakeLists.txt
+++ b/libclc/CMakeLists.txt
@@ -24,8 +24,8 @@ option(
 
 # List of all supported architectures.
 set( LIBCLC_ARCHS_ALL amdgpu amdgcn nvptx64 )
-set( LIBCLC_ARCHS_SPIRV spirv spirv32 spirv64)
-list( APPEND LIBCLC_ARCHS_ALL ${LIBCLC_ARCHS_SPIRV})
+set( LIBCLC_ARCHS_SPIRV spirv spirv32 spirv64 )
+list( APPEND LIBCLC_ARCHS_ALL ${LIBCLC_ARCHS_SPIRV} )
 
 set(LIBCLC_TARGET ${LLVM_DEFAULT_TARGET_TRIPLE})
 
@@ -33,10 +33,13 @@ if(NOT LIBCLC_TARGET)
   message(FATAL_ERROR "libclc target is empty\n")
 endif()
 
-string( REPLACE "-" ";" _target_components ${LIBCLC_TARGET} )
-list(GET _target_components 0 _target_arch)
-if(NOT "${_target_arch}" IN_LIST LIBCLC_ARCHS_ALL)
-  message(FATAL_ERROR "Unknown libclc target architecture: ${_target_arch}\n"
+# Parse the target triple into arch and OS components.
+string(REPLACE "-" ";" triple_components ${LIBCLC_TARGET})
+list(GET triple_components 0 LIBCLC_TARGET_ARCH)
+list(GET triple_components 2 LIBCLC_TARGET_OS)
+
+if(NOT "${LIBCLC_TARGET_ARCH}" IN_LIST LIBCLC_ARCHS_ALL)
+  message(FATAL_ERROR "Unknown libclc target architecture: ${LIBCLC_TARGET_ARCH}\n"
     "Target was: ${LIBCLC_TARGET}\n"
     "Valid architectures are: ${LIBCLC_ARCHS_ALL}\n")
 endif()
@@ -98,12 +101,17 @@ endif()
 
 message(STATUS "libclc target '${LIBCLC_TARGET}' is enabled")
 
-string( REPLACE "-" ";" TRIPLE  ${LIBCLC_TARGET} )
-list(GET TRIPLE 0 ARCH)
-list(GET TRIPLE 2 OS)
+# Map the LLVM target architecture to the standard directory name.
+if(LIBCLC_TARGET_ARCH STREQUAL amdgcn OR LIBCLC_TARGET_ARCH STREQUAL amdgpu)
+  set(LIBCLC_ARCH_DIR amdgpu)
+elseif(LIBCLC_TARGET_ARCH STREQUAL nvptx64)
+  set(LIBCLC_ARCH_DIR nvptx)
+elseif(LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
+  set(LIBCLC_ARCH_DIR spirv)
+endif()
 
-if(ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
-  if(NOT OS STREQUAL vulkan AND NOT LIBCLC_USE_SPIRV_BACKEND AND NOT llvm-spirv_exe)
+if(LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
+  if(NOT LIBCLC_TARGET_OS STREQUAL vulkan AND NOT LIBCLC_USE_SPIRV_BACKEND AND NOT llvm-spirv_exe)
     message(FATAL_ERROR "SPIR-V backend or llvm-spirv is required for libclc ${LIBCLC_TARGET}")
   endif()
 endif()
@@ -114,35 +122,12 @@ foreach( tool IN ITEMS opt llvm-link )
   endif()
 endforeach()
 
-add_subdirectory(clc/lib/generic)
-add_subdirectory(opencl/lib/generic)
-
-if(ARCH STREQUAL amdgcn)
-  add_subdirectory(clc/lib/amdgpu)
-  add_subdirectory(opencl/lib/amdgpu)
-elseif(ARCH STREQUAL nvptx64)
-  add_subdirectory(clc/lib/ptx-nvidiacl)
-elseif(ARCH STREQUAL spirv OR ARCH STREQUAL spirv32 OR ARCH STREQUAL spirv64)
-  if(OS STREQUAL vulkan)
-    add_subdirectory(clc/lib/vulkan)
-    add_subdirectory(opencl/lib/vulkan)
-  else()
-    add_subdirectory(clc/lib/spirv)
-    add_subdirectory(opencl/lib/spirv)
-  endif()
-endif()
-
-add_custom_target( libclc ALL )
-
-add_custom_target( libclc-opencl-builtins COMMENT "Build libclc OpenCL builtins" )
-add_dependencies( libclc libclc-opencl-builtins )
-
 # Determine the clang target triple. Vulkan and SPIR-V backend targets use the
 # triple directly; other SPIR-V targets fall back to the legacy SPIR target.
 set(clang_triple ${LIBCLC_TARGET})
-if(ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
-  if(NOT OS STREQUAL vulkan AND NOT LIBCLC_USE_SPIRV_BACKEND)
-    if(ARCH STREQUAL spirv)
+if(LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
+  if(NOT LIBCLC_TARGET_OS STREQUAL vulkan AND NOT LIBCLC_USE_SPIRV_BACKEND)
+    if(LIBCLC_TARGET_ARCH STREQUAL spirv)
       set(clang_triple spir--)
     else()
       set(clang_triple spir64--)
@@ -153,10 +138,10 @@ endif()
 # Address space values.
 set(private_addrspace_val 0)
 set(generic_addrspace_val 0)
-if(ARCH STREQUAL amdgcn)
+if(LIBCLC_TARGET_ARCH STREQUAL amdgcn)
   set(private_addrspace_val 5)
 endif()
-if(ARCH IN_LIST LIBCLC_ARCHS_SPIRV AND NOT OS STREQUAL vulkan)
+if(LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV AND NOT LIBCLC_TARGET_OS STREQUAL vulkan)
   set(generic_addrspace_val 4)
 endif()
 
@@ -165,50 +150,18 @@ set(target_compile_flags)
 set(target_extra_defines)
 set(opt_flags -O3)
 
-if(ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
-  if(OS STREQUAL vulkan)
+if(LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
+  if(LIBCLC_TARGET_OS STREQUAL vulkan)
     list(APPEND target_compile_flags -Wno-unknown-assumption -U__opencl_c_int64)
   else()
     list(APPEND target_compile_flags -O0 -finline-hint-functions)
     list(APPEND target_extra_defines CLC_SPIRV)
     set(opt_flags)
   endif()
-elseif(ARCH STREQUAL amdgcn)
+elseif(LIBCLC_TARGET_ARCH STREQUAL amdgcn)
   list(APPEND target_compile_flags "SHELL:-Xclang -mcode-object-version=none")
 endif()
 
-# Collect CLC sources; target-specific sources override generic ones by basename.
-set(_clc_overrides)
-if(ARCH STREQUAL amdgcn)
-  list(APPEND _clc_overrides ${CLC_AMDGPU_SOURCES})
-elseif(ARCH STREQUAL nvptx64 AND (OS STREQUAL nvidiacl OR OS STREQUAL cuda))
-  list(APPEND _clc_overrides ${CLC_PTX_NVIDIACL_SOURCES})
-elseif(ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
-  if(OS STREQUAL vulkan)
-    list(APPEND _clc_overrides ${CLC_VULKAN_SOURCES})
-  else()
-    list(APPEND _clc_overrides ${CLC_SPIRV_SOURCES})
-  endif()
-endif()
-libclc_merge_sources(clc_sources ${CLC_GENERIC_SOURCES} ${_clc_overrides})
-
-# Collect OpenCL sources. SPIR-V and Vulkan targets use self-contained
-# subsets while others merge with target-specific overrides.
-if(ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
-  if(OS STREQUAL vulkan)
-    set(opencl_sources ${OPENCL_VULKAN_SOURCES})
-  else()
-    set(opencl_sources ${OPENCL_SPIRV_SOURCES})
-  endif()
-else()
-  set(_opencl_overrides)
-  if(ARCH STREQUAL amdgcn)
-    list(APPEND _opencl_overrides ${OPENCL_AMDGCN_SOURCES})
-  endif()
-  libclc_merge_sources(opencl_sources
-    ${OPENCL_GENERIC_SOURCES} ${_opencl_overrides})
-endif()
-
 # Common compile options shared by CLC and OpenCL libraries.
 set(compile_flags
   -flto
@@ -227,35 +180,45 @@ set(compile_flags
   ${target_compile_flags}
 )
 
-set(_common_defs
+set(common_defs
   ${target_extra_defines}
   __CLC_PRIVATE_ADDRSPACE_VAL=${private_addrspace_val}
   __CLC_GENERIC_ADDRSPACE_VAL=${generic_addrspace_val}
 )
 
-# Build the CLC internal builtins library.
-string(REPLACE "-" "_" lib_suffix ${LIBCLC_TARGET})
-set(clc_lib clc_builtins_${lib_suffix})
-add_libclc_builtin_library(${clc_lib}
-  SOURCES ${clc_sources}
+add_custom_target(libclc ALL)
+add_custom_target(libclc-opencl-builtins COMMENT "Build libclc OpenCL builtins")
+add_dependencies(libclc libclc-opencl-builtins)
+
+# Configure the CLC internal builtins library.
+set(LIBCLC_CLC_TARGET clc)
+libclc_add_builtin_library(${LIBCLC_CLC_TARGET}
   COMPILE_OPTIONS ${compile_flags}
   INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR}/clc/include
-  COMPILE_DEFINITIONS ${_common_defs}
+  COMPILE_DEFINITIONS ${common_defs}
   FOLDER "libclc/Device IR/CLC"
 )
 
-# Build, link, and install the final OpenCL builtins library.
-add_libclc_library(libclc-${LIBCLC_TARGET}
-  ARCH ${ARCH}
-  TRIPLE ${clang_triple}
-  TARGET_TRIPLE ${LIBCLC_TARGET}
-  SOURCES ${opencl_sources}
+set(LIBCLC_OPENCL_TARGET opencl)
+libclc_add_builtin_library(${LIBCLC_OPENCL_TARGET}
   COMPILE_OPTIONS ${compile_flags} "SHELL:-Xclang -fdeclare-opencl-builtins"
   INCLUDE_DIRS
     ${CMAKE_CURRENT_SOURCE_DIR}/clc/include
     ${CMAKE_CURRENT_SOURCE_DIR}/opencl/include
-  COMPILE_DEFINITIONS ${_common_defs}
-  INTERNALIZE_LIBRARIES ${clc_lib}
+  COMPILE_DEFINITIONS ${common_defs}
+  FOLDER "libclc/Device IR/Intermediate"
+)
+
+add_subdirectory(clc)
+add_subdirectory(opencl)
+
+# Link and install the final OpenCL builtins library.
+libclc_add_library(libclc-${LIBCLC_TARGET}
+  ARCH ${LIBCLC_TARGET_ARCH}
+  TRIPLE ${clang_triple}
+  TARGET_TRIPLE ${LIBCLC_TARGET}
+  LIBRARIES ${LIBCLC_OPENCL_TARGET}
+  INTERNALIZE_LIBRARIES ${LIBCLC_CLC_TARGET}
   OPT_FLAGS ${opt_flags}
   OUTPUT_FILENAME libclc
   PARENT_TARGET libclc-opencl-builtins
diff --git a/libclc/clc/CMakeLists.txt b/libclc/clc/CMakeLists.txt
new file mode 100644
index 000000000000..bd75adcf7524
--- /dev/null
+++ b/libclc/clc/CMakeLists.txt
@@ -0,0 +1,5 @@
+# Add the target specific files first so they can override the generic fallback.
+if(LIBCLC_ARCH_DIR AND EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/lib/${LIBCLC_ARCH_DIR})
+  add_subdirectory(lib/${LIBCLC_ARCH_DIR})
+endif()
+add_subdirectory(lib/generic)
diff --git a/libclc/clc/lib/amdgpu/CMakeLists.txt b/libclc/clc/lib/amdgpu/CMakeLists.txt
index a5cd47fab446..910a0cf1765d 100644
--- a/libclc/clc/lib/amdgpu/CMakeLists.txt
+++ b/libclc/clc/lib/amdgpu/CMakeLists.txt
@@ -1,5 +1,4 @@
-libclc_configure_source_list(CLC_AMDGPU_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
+libclc_add_sources(${LIBCLC_CLC_TARGET} FILES
   address_space/clc_qualifier.cl
   math/clc_cbrt.cl
   math/clc_exp.cl
@@ -45,9 +44,10 @@ libclc_configure_source_list(CLC_AMDGPU_SOURCES
   workitem/clc_get_num_sub_groups.cl
   workitem/clc_get_sub_group_id.cl
   workitem/clc_get_sub_group_size.cl
-  workitem/clc_get_work_dim.cl)
+  workitem/clc_get_work_dim.cl
+)
 
-libclc_configure_source_options(${CMAKE_CURRENT_SOURCE_DIR} -fapprox-func
+libclc_set_source_options(-fapprox-func
   math/clc_native_exp.cl
   math/clc_native_exp2.cl
   math/clc_native_log10.cl
diff --git a/libclc/clc/lib/generic/CMakeLists.txt b/libclc/clc/lib/generic/CMakeLists.txt
index 168a0f1ff1e8..40261545fce9 100644
--- a/libclc/clc/lib/generic/CMakeLists.txt
+++ b/libclc/clc/lib/generic/CMakeLists.txt
@@ -1,5 +1,4 @@
-libclc_configure_source_list(CLC_GENERIC_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
+libclc_add_sources(${LIBCLC_CLC_TARGET} FILES
   async/clc_prefetch.cl
   atomic/clc_atomic_compare_exchange.cl
   atomic/clc_atomic_dec.cl
@@ -209,7 +208,7 @@ libclc_configure_source_list(CLC_GENERIC_SOURCES
   workitem/clc_get_sub_group_size.cl
 )
 
-libclc_configure_source_options(${CMAKE_CURRENT_SOURCE_DIR} -fapprox-func
+libclc_set_source_options(-fapprox-func
   math/clc_native_cos.cl
   math/clc_native_divide.cl
   math/clc_native_exp.cl
@@ -226,8 +225,10 @@ libclc_configure_source_options(${CMAKE_CURRENT_SOURCE_DIR} -fapprox-func
   math/clc_native_tan.cl
   math/clc_div_fast.cl
   math/clc_recip_fast.cl
-  math/clc_sqrt_fast.cl)
+  math/clc_sqrt_fast.cl
+)
 
-libclc_configure_source_options(${CMAKE_CURRENT_SOURCE_DIR} -cl-fp32-correctly-rounded-divide-sqrt
+libclc_set_source_options(-cl-fp32-correctly-rounded-divide-sqrt
   math/clc_div_cr.cl
-  math/clc_sqrt_cr.cl)
+  math/clc_sqrt_cr.cl
+)
diff --git a/libclc/clc/lib/ptx-nvidiacl/CMakeLists.txt b/libclc/clc/lib/nvptx/CMakeLists.txt
similarity index 83%
rename from libclc/clc/lib/ptx-nvidiacl/CMakeLists.txt
rename to libclc/clc/lib/nvptx/CMakeLists.txt
index 6eb0baab1c0b..2345d5aeed77 100644
--- a/libclc/clc/lib/ptx-nvidiacl/CMakeLists.txt
+++ b/libclc/clc/lib/nvptx/CMakeLists.txt
@@ -1,5 +1,4 @@
-libclc_configure_source_list(CLC_PTX_NVIDIACL_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
+libclc_add_sources(${LIBCLC_CLC_TARGET} FILES
   math/clc_log.cl
   math/clc_rsqrt.cl
   math/clc_sinpi.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/math/clc_log.cl b/libclc/clc/lib/nvptx/math/clc_log.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/math/clc_log.cl
rename to libclc/clc/lib/nvptx/math/clc_log.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/math/clc_rsqrt.cl b/libclc/clc/lib/nvptx/math/clc_rsqrt.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/math/clc_rsqrt.cl
rename to libclc/clc/lib/nvptx/math/clc_rsqrt.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/math/clc_sinpi.cl b/libclc/clc/lib/nvptx/math/clc_sinpi.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/math/clc_sinpi.cl
rename to libclc/clc/lib/nvptx/math/clc_sinpi.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/math/clc_sqrt.cl b/libclc/clc/lib/nvptx/math/clc_sqrt.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/math/clc_sqrt.cl
rename to libclc/clc/lib/nvptx/math/clc_sqrt.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/relational/clc_isinf.cl b/libclc/clc/lib/nvptx/relational/clc_isinf.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/relational/clc_isinf.cl
rename to libclc/clc/lib/nvptx/relational/clc_isinf.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/synchronization/clc_work_group_barrier.cl b/libclc/clc/lib/nvptx/synchronization/clc_work_group_barrier.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/synchronization/clc_work_group_barrier.cl
rename to libclc/clc/lib/nvptx/synchronization/clc_work_group_barrier.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_global_id.cl b/libclc/clc/lib/nvptx/workitem/clc_get_global_id.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_global_id.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_global_id.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_global_size.cl b/libclc/clc/lib/nvptx/workitem/clc_get_global_size.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_global_size.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_global_size.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_group_id.cl b/libclc/clc/lib/nvptx/workitem/clc_get_group_id.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_group_id.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_group_id.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_local_id.cl b/libclc/clc/lib/nvptx/workitem/clc_get_local_id.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_local_id.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_local_id.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_local_size.cl b/libclc/clc/lib/nvptx/workitem/clc_get_local_size.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_local_size.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_local_size.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_max_sub_group_size.cl b/libclc/clc/lib/nvptx/workitem/clc_get_max_sub_group_size.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_max_sub_group_size.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_max_sub_group_size.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_num_groups.cl b/libclc/clc/lib/nvptx/workitem/clc_get_num_groups.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_num_groups.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_num_groups.cl
diff --git a/libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_sub_group_local_id.cl b/libclc/clc/lib/nvptx/workitem/clc_get_sub_group_local_id.cl
similarity index 100%
rename from libclc/clc/lib/ptx-nvidiacl/workitem/clc_get_sub_group_local_id.cl
rename to libclc/clc/lib/nvptx/workitem/clc_get_sub_group_local_id.cl
diff --git a/libclc/clc/lib/spirv/CMakeLists.txt b/libclc/clc/lib/spirv/CMakeLists.txt
index b7481615b941..5f361c95c400 100644
--- a/libclc/clc/lib/spirv/CMakeLists.txt
+++ b/libclc/clc/lib/spirv/CMakeLists.txt
@@ -1,5 +1,8 @@
-libclc_configure_source_list(CLC_SPIRV_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
+if(LIBCLC_TARGET_OS AND EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBCLC_TARGET_OS})
+  add_subdirectory(${LIBCLC_TARGET_OS})
+endif()
+
+libclc_add_sources(${LIBCLC_CLC_TARGET} FILES
   math/clc_fmax.cl
   math/clc_fmin.cl
   subnormal_config.cl
diff --git a/libclc/clc/lib/spirv/vulkan/CMakeLists.txt b/libclc/clc/lib/spirv/vulkan/CMakeLists.txt
new file mode 100644
index 000000000000..499ce274a500
--- /dev/null
+++ b/libclc/clc/lib/spirv/vulkan/CMakeLists.txt
@@ -0,0 +1,4 @@
+libclc_add_sources(${LIBCLC_CLC_TARGET} FILES
+  integer/clc_mul_hi.cl
+  math/clc_sw_fma.cl
+)
diff --git a/libclc/clc/lib/vulkan/integer/clc_mul_hi.cl b/libclc/clc/lib/spirv/vulkan/integer/clc_mul_hi.cl
similarity index 100%
rename from libclc/clc/lib/vulkan/integer/clc_mul_hi.cl
rename to libclc/clc/lib/spirv/vulkan/integer/clc_mul_hi.cl
diff --git a/libclc/clc/lib/vulkan/math/clc_sw_fma.cl b/libclc/clc/lib/spirv/vulkan/math/clc_sw_fma.cl
similarity index 100%
rename from libclc/clc/lib/vulkan/math/clc_sw_fma.cl
rename to libclc/clc/lib/spirv/vulkan/math/clc_sw_fma.cl
diff --git a/libclc/clc/lib/vulkan/CMakeLists.txt b/libclc/clc/lib/vulkan/CMakeLists.txt
deleted file mode 100644
index 172e3be32d65..000000000000
--- a/libclc/clc/lib/vulkan/CMakeLists.txt
+++ /dev/null
@@ -1,5 +0,0 @@
-libclc_configure_source_list(CLC_VULKAN_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
-  integer/clc_mul_hi.cl
-  math/clc_sw_fma.cl
-)
diff --git a/libclc/cmake/modules/AddLibclc.cmake b/libclc/cmake/modules/AddLibclc.cmake
index 41297e8eb1e9..2d547e13a4e0 100644
--- a/libclc/cmake/modules/AddLibclc.cmake
+++ b/libclc/cmake/modules/AddLibclc.cmake
@@ -1,67 +1,71 @@
-# Converts a list of relative source paths to absolute paths and exports
-# it to the parent scope.
-macro(libclc_configure_source_list variable path)
-  set(${variable} ${ARGN})
-  list(TRANSFORM ${variable} PREPEND "${path}/")
-  set(${variable} ${${variable}} PARENT_SCOPE)
-endmacro()
-
-# Appends a compile option to the given source files. Paths are relative
-# to `path` and the property is set in the top-level libclc directory scope.
-macro(libclc_configure_source_options path option)
-  set(_option_srcs ${ARGN})
-  list(TRANSFORM _option_srcs PREPEND "${path}/")
-  set_property(SOURCE ${_option_srcs}
-    DIRECTORY ${LIBCLC_SOURCE_DIR}
-    APPEND PROPERTY COMPILE_OPTIONS ${option}
-  )
-endmacro()
-
-# Merges OpenCL C source file lists with priority deduplication.
+# Adds source files to a libclc builtin library target with deduplication. If a
+# source with the same basename already exists in the target's SOURCES property
+# the new file is skipped. This enables target-specific directories to override
+# generic implementations when they are included first.
 #
-# All arguments after the output variable name are treated as source file
-# paths. When multiple files share the same basename, the last occurrence
-# wins. This allows target-specific files to automatically override generic
-# ones.
-function(libclc_merge_sources output)
-  set(all_sources ${ARGN})
-  set(result)
-  set(seen_names)
+# Sources are specified as paths relative to CMAKE_CURRENT_SOURCE_DIR, or
+# relative to BASE_DIR if provided.
+function(libclc_add_sources target)
+  cmake_parse_arguments(ARG "" "BASE_DIR" "FILES" ${ARGN})
+  if(NOT ARG_BASE_DIR)
+    set(ARG_BASE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
+  endif()
 
-  list(REVERSE all_sources)
-  foreach(f ${all_sources})
-    get_filename_component(name "${f}" NAME)
-    if(NOT name IN_LIST seen_names)
-      list(APPEND seen_names "${name}")
-      list(PREPEND result "${f}")
+  get_target_property(existing ${target} SOURCES)
+
+  set(seen)
+  foreach(file IN LISTS existing)
+    get_filename_component(name "${file}" NAME)
+    list(APPEND seen "${name}")
+  endforeach()
+
+  set(new_sources)
+  foreach(rel_src IN LISTS ARG_FILES)
+    get_filename_component(name "${rel_src}" NAME)
+    if(NOT name IN_LIST seen)
+      list(APPEND new_sources "${ARG_BASE_DIR}/${rel_src}")
+      list(APPEND seen "${name}")
     endif()
   endforeach()
 
-  set(${output} ${result} PARENT_SCOPE)
+  if(new_sources)
+    target_sources(${target} PRIVATE ${new_sources})
+    set(inc_dirs)
+    foreach(file IN LISTS new_sources)
+      get_filename_component(dir "${file}" DIRECTORY)
+      list(APPEND inc_dirs "${dir}")
+    endforeach()
+    list(REMOVE_DUPLICATES inc_dirs)
+    target_include_directories(${target} PRIVATE ${inc_dirs})
+  endif()
 endfunction()
 
-# Creates a static library target for libclc builtins. Derives include
-# directories to locate `.inc` files in the same directory.
-function(add_libclc_builtin_library target_name)
+# Appends a compile option to the given source files. Source paths are
+# relative to CMAKE_CURRENT_SOURCE_DIR. The property is set in the
+# top-level libclc directory scope.
+function(libclc_set_source_options option)
+  set(srcs ${ARGN})
+  list(TRANSFORM srcs PREPEND "${CMAKE_CURRENT_SOURCE_DIR}/")
+  set_property(SOURCE ${srcs}
+    DIRECTORY ${LIBCLC_SOURCE_DIR}
+    APPEND PROPERTY COMPILE_OPTIONS ${option}
+  )
+endfunction()
+
+# Creates a static library target for libclc builtins and configures its
+# compile options, include directories, and definitions. Subdirectories
+# populate sources via libclc_add_sources() after this call.
+function(libclc_add_builtin_library target_name)
   cmake_parse_arguments(ARG
     ""
     "FOLDER"
-    "SOURCES;COMPILE_OPTIONS;INCLUDE_DIRS;COMPILE_DEFINITIONS"
+    "COMPILE_OPTIONS;INCLUDE_DIRS;COMPILE_DEFINITIONS"
     ${ARGN}
   )
 
-  set(_inc_dirs)
-  foreach(f ${ARG_SOURCES})
-    get_filename_component(dir ${f} DIRECTORY)
-    list(APPEND _inc_dirs ${dir})
-  endforeach()
-  list(REMOVE_DUPLICATES _inc_dirs)
-
-  add_library(${target_name} STATIC ${ARG_SOURCES})
+  add_library(${target_name} STATIC)
   target_compile_options(${target_name} PRIVATE ${ARG_COMPILE_OPTIONS})
-  target_include_directories(${target_name} PRIVATE
-    ${ARG_INCLUDE_DIRS} ${_inc_dirs}
-  )
+  target_include_directories(${target_name} PRIVATE ${ARG_INCLUDE_DIRS})
   target_compile_definitions(${target_name} PRIVATE ${ARG_COMPILE_DEFINITIONS})
   set_target_properties(${target_name} PROPERTIES
     ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
@@ -71,7 +75,7 @@ endfunction()
 
 # Links one or more libclc builtin libraries together, optionally
 # internalizing dependencies, then produces a final .bc or .spv file.
-function(link_libclc_builtin_library target_name)
+function(libclc_link_library target_name)
   cmake_parse_arguments(ARG
     ""
     "ARCH;TRIPLE;TARGET_TRIPLE;FOLDER;OUTPUT_FILENAME"
@@ -80,10 +84,10 @@ function(link_libclc_builtin_library target_name)
   )
 
   if(NOT ARG_OUTPUT_FILENAME)
-    message(FATAL_ERROR "OUTPUT_FILENAME is required for link_libclc_builtin_library")
+    message(FATAL_ERROR "OUTPUT_FILENAME is required for libclc_link_library")
   endif()
   if(NOT ARG_LIBRARIES)
-    message(FATAL_ERROR "LIBRARIES is required for link_libclc_builtin_library")
+    message(FATAL_ERROR "LIBRARIES is required for libclc_link_library")
   endif()
 
   set(library_dir ${LIBCLC_OUTPUT_LIBRARY_DIR}/${ARG_TARGET_TRIPLE})
@@ -113,7 +117,7 @@ function(link_libclc_builtin_library target_name)
 
   string(REPLACE "-" ";" triple_parts "${ARG_TRIPLE}")
   list(GET triple_parts 2 triple_os)
-  if((ARG_ARCH STREQUAL spirv OR ARG_ARCH STREQUAL spirv32 OR ARG_ARCH STREQUAL spirv64) AND NOT triple_os STREQUAL vulkan)
+  if(ARG_ARCH IN_LIST LIBCLC_ARCHS_SPIRV AND NOT triple_os STREQUAL vulkan)
     # SPIR-V targets produce a .spv file from the linked bitcode.
     set(builtins_lib ${library_dir}/${ARG_OUTPUT_FILENAME}.spv)
     if(LIBCLC_USE_SPIRV_BACKEND)
@@ -148,41 +152,31 @@ function(link_libclc_builtin_library target_name)
   )
 endfunction()
 
-# Builds a builtins library from sources, links it with any internalized
-# dependencies via link_libclc_builtin_library, and adds a verification test
-# for unresolved symbols.
-function(add_libclc_library target_name)
+# Links builtin library targets, produces the final output file, and
+# registers it for installation.
+function(libclc_add_library target_name)
   cmake_parse_arguments(ARG
     ""
     "ARCH;TRIPLE;TARGET_TRIPLE;OUTPUT_FILENAME;PARENT_TARGET"
-    "SOURCES;COMPILE_OPTIONS;INCLUDE_DIRS;COMPILE_DEFINITIONS;INTERNALIZE_LIBRARIES;OPT_FLAGS"
+    "LIBRARIES;INTERNALIZE_LIBRARIES;OPT_FLAGS"
     ${ARGN}
   )
 
   if(NOT ARG_OUTPUT_FILENAME)
-    message(FATAL_ERROR "OUTPUT_FILENAME is required for add_libclc_library")
+    message(FATAL_ERROR "OUTPUT_FILENAME is required for libclc_add_library")
   endif()
   if(NOT ARG_PARENT_TARGET)
-    message(FATAL_ERROR "PARENT_TARGET is required for add_libclc_library")
+    message(FATAL_ERROR "PARENT_TARGET is required for libclc_add_library")
   endif()
-  if(NOT ARG_SOURCES)
-    message(FATAL_ERROR "SOURCES is required for add_libclc_library")
+  if(NOT ARG_LIBRARIES)
+    message(FATAL_ERROR "LIBRARIES is required for libclc_add_library")
   endif()
 
-  set(builtins_target ${target_name}_clc_builtins)
-  add_libclc_builtin_library(${builtins_target}
-    SOURCES ${ARG_SOURCES}
-    COMPILE_OPTIONS ${ARG_COMPILE_OPTIONS}
-    INCLUDE_DIRS ${ARG_INCLUDE_DIRS}
-    COMPILE_DEFINITIONS ${ARG_COMPILE_DEFINITIONS}
-    FOLDER "libclc/Device IR/Intermediate"
-  )
-
-  link_libclc_builtin_library(${target_name}
+  libclc_link_library(${target_name}
     ARCH ${ARG_ARCH}
     TRIPLE ${ARG_TRIPLE}
     TARGET_TRIPLE ${ARG_TARGET_TRIPLE}
-    LIBRARIES ${builtins_target}
+    LIBRARIES ${ARG_LIBRARIES}
     INTERNALIZE_LIBRARIES ${ARG_INTERNALIZE_LIBRARIES}
     OPT_FLAGS ${ARG_OPT_FLAGS}
     OUTPUT_FILENAME "${ARG_OUTPUT_FILENAME}"
diff --git a/libclc/opencl/CMakeLists.txt b/libclc/opencl/CMakeLists.txt
new file mode 100644
index 000000000000..8b4ac40ea827
--- /dev/null
+++ b/libclc/opencl/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Add the target specific files first so they can override the generic fallback.
+if(LIBCLC_ARCH_DIR AND EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/lib/${LIBCLC_ARCH_DIR})
+  add_subdirectory(lib/${LIBCLC_ARCH_DIR})
+endif()
+
+# SPIR-V targets cannot use the generic list of generic functions yet.
+if(NOT LIBCLC_TARGET_ARCH IN_LIST LIBCLC_ARCHS_SPIRV)
+  add_subdirectory(lib/generic)
+endif()
diff --git a/libclc/opencl/lib/amdgpu/CMakeLists.txt b/libclc/opencl/lib/amdgpu/CMakeLists.txt
index a42f2751906b..16a75349d8a4 100644
--- a/libclc/opencl/lib/amdgpu/CMakeLists.txt
+++ b/libclc/opencl/lib/amdgpu/CMakeLists.txt
@@ -1,5 +1,4 @@
-libclc_configure_source_list(OPENCL_AMDGCN_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
+libclc_add_sources(${LIBCLC_OPENCL_TARGET} FILES
   async/wait_group_events.cl
   printf/__printf_alloc.cl
 )
diff --git a/libclc/opencl/lib/generic/CMakeLists.txt b/libclc/opencl/lib/generic/CMakeLists.txt
index 4ad60248139a..5768ba9446ff 100644
--- a/libclc/opencl/lib/generic/CMakeLists.txt
+++ b/libclc/opencl/lib/generic/CMakeLists.txt
@@ -1,5 +1,4 @@
-libclc_configure_source_list(OPENCL_GENERIC_SOURCES
-  ${CMAKE_CURRENT_SOURCE_DIR}
+libclc_add_sources(${LIBCLC_OPENCL_TARGET} FILES
   address_space/qualifier.cl
   async/async_work_group_copy.cl
   async/async_work_group_strided_copy.cl
@@ -227,7 +226,7 @@ libclc_configure_source_list(OPENCL_GENERIC_SOURCES
   workitem/get_work_dim.cl
 )
 
-libclc_configure_source_options(${CMAKE_CURRENT_SOURCE_DIR} -fapprox-func
+libclc_set_source_options(-fapprox-func
   math/native_cos.cl
   math/native_divide.cl
   math/native_exp.cl
diff --git a/libclc/opencl/lib/spirv/CMakeLists.txt b/libclc/opencl/lib/spirv/CMakeLists.txt
index ab6fea0692c0..ea35940f60d7 100644
--- a/libclc/opencl/lib/spirv/CMakeLists.txt
+++ b/libclc/opencl/lib/spirv/CMakeLists.txt
@@ -1,9 +1,12 @@
-set(_gen ${CMAKE_CURRENT_SOURCE_DIR}/../generic)
+if(LIBCLC_TARGET_OS AND EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBCLC_TARGET_OS})
+  add_subdirectory(${LIBCLC_TARGET_OS})
+  return()
+endif()
 
-# SPIR-V uses a curated subset of generic builtins, so this list is
-# self-contained rather than merged with the generic set.
-libclc_configure_source_list(OPENCL_SPIRV_SOURCES
-  ${_gen}
+# Non-Vulkan SPIR-V uses a curated subset of generic builtins.
+libclc_add_sources(${LIBCLC_OPENCL_TARGET}
+  BASE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../generic
+  FILES
   async/async_work_group_strided_copy.cl
   async/wait_group_events.cl
   common/degrees.cl
diff --git a/libclc/opencl/lib/vulkan/CMakeLists.txt b/libclc/opencl/lib/spirv/vulkan/CMakeLists.txt
similarity index 85%
rename from libclc/opencl/lib/vulkan/CMakeLists.txt
rename to libclc/opencl/lib/spirv/vulkan/CMakeLists.txt
index 5fa2e7a36767..d04959027f0d 100644
--- a/libclc/opencl/lib/vulkan/CMakeLists.txt
+++ b/libclc/opencl/lib/spirv/vulkan/CMakeLists.txt
@@ -1,9 +1,6 @@
-set(_gen ${CMAKE_CURRENT_SOURCE_DIR}/../generic)
-
 # Vulkan uses a curated subset of generic builtins plus its own overrides,
 # so this list is self-contained rather than merged with the generic set.
-libclc_configure_source_list(_vulkan_sources
-  ${CMAKE_CURRENT_SOURCE_DIR}
+libclc_add_sources(${LIBCLC_OPENCL_TARGET} FILES
   conversion/convert_float2float.cl
   conversion/convert_float2int.cl
   conversion/convert_int2float.cl
@@ -12,8 +9,9 @@ libclc_configure_source_list(_vulkan_sources
   shared/vstore_half.cl
 )
 
-libclc_configure_source_list(_gen_sources
-  ${_gen}
+libclc_add_sources(${LIBCLC_OPENCL_TARGET}
+  BASE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/../../generic
+  FILES
   geometric/distance.cl
   geometric/length.cl
   math/acos.cl
@@ -84,5 +82,3 @@ libclc_configure_source_list(_gen_sources
   math/tanpi.cl
   math/tgamma.cl
 )
-
-set(OPENCL_VULKAN_SOURCES ${_vulkan_sources} ${_gen_sources} PARENT_SCOPE)
diff --git a/libclc/opencl/lib/vulkan/conversion/convert_float.inc b/libclc/opencl/lib/spirv/vulkan/conversion/convert_float.inc
similarity index 100%
rename from libclc/opencl/lib/vulkan/conversion/convert_float.inc
rename to libclc/opencl/lib/spirv/vulkan/conversion/convert_float.inc
diff --git a/libclc/opencl/lib/vulkan/conversion/convert_float2float.cl b/libclc/opencl/lib/spirv/vulkan/conversion/convert_float2float.cl
similarity index 100%
rename from libclc/opencl/lib/vulkan/conversion/convert_float2float.cl
rename to libclc/opencl/lib/spirv/vulkan/conversion/convert_float2float.cl
diff --git a/libclc/opencl/lib/vulkan/conversion/convert_float2int.cl b/libclc/opencl/lib/spirv/vulkan/conversion/convert_float2int.cl
similarity index 100%
rename from libclc/opencl/lib/vulkan/conversion/convert_float2int.cl
rename to libclc/opencl/lib/spirv/vulkan/conversion/convert_float2int.cl
diff --git a/libclc/opencl/lib/vulkan/conversion/convert_int2float.cl b/libclc/opencl/lib/spirv/vulkan/conversion/convert_int2float.cl
similarity index 100%
rename from libclc/opencl/lib/vulkan/conversion/convert_int2float.cl
rename to libclc/opencl/lib/spirv/vulkan/conversion/convert_int2float.cl
diff --git a/libclc/opencl/lib/vulkan/conversion/convert_integer.cl b/libclc/opencl/lib/spirv/vulkan/conversion/convert_integer.cl
similarity index 100%
rename from libclc/opencl/lib/vulkan/conversion/convert_integer.cl
rename to libclc/opencl/lib/spirv/vulkan/conversion/convert_integer.cl
diff --git a/libclc/opencl/lib/vulkan/conversion/convert_integer.inc b/libclc/opencl/lib/spirv/vulkan/conversion/convert_integer.inc
similarity index 100%
rename from libclc/opencl/lib/vulkan/conversion/convert_integer.inc
rename to libclc/opencl/lib/spirv/vulkan/conversion/convert_integer.inc
diff --git a/libclc/opencl/lib/vulkan/math/fma.cl b/libclc/opencl/lib/spirv/vulkan/math/fma.cl
similarity index 100%
rename from libclc/opencl/lib/vulkan/math/fma.cl
rename to libclc/opencl/lib/spirv/vulkan/math/fma.cl
diff --git a/libclc/opencl/lib/vulkan/shared/vstore_half.cl b/libclc/opencl/lib/spirv/vulkan/shared/vstore_half.cl
similarity index 100%
rename from libclc/opencl/lib/vulkan/shared/vstore_half.cl
rename to libclc/opencl/lib/spirv/vulkan/shared/vstore_half.cl
diff --git a/libclc/opencl/lib/vulkan/shared/vstore_half.inc b/libclc/opencl/lib/spirv/vulkan/shared/vstore_half.inc
similarity index 100%
rename from libclc/opencl/lib/vulkan/shared/vstore_half.inc
rename to libclc/opencl/lib/spirv/vulkan/shared/vstore_half.inc