shylie/llvm-project
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[libclc] Add an option to build SPIR-V targets with the LLVM backend (#151347)

Browse Source 
This removes the dependency on an external tool to build the SPIR-V
files. It may be of interest to projects such as Mesa.

Note that the option is off by default as using the SPIR-V backend, at
least on my machine, uses a *lot* of memory and the process is often
killed in a parallelized build. It does complete, however.

Fixes #135327.
This commit is contained in:
Fraser Cormack 2025-08-01 09:48:40 +01:00 committed by GitHub
parent 673476d96b
commit b0313adefa
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 44 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
libclc/CMakeLists.txt
View File

@ -42,6 +42,10 @@ set( LIBCLC_TARGETS_TO_BUILD "all"
option( ENABLE_RUNTIME_SUBNORMAL "Enable runtime linking of subnormal support." OFF )
option(
LIBCLC_USE_SPIRV_BACKEND "Build SPIR-V targets with the SPIR-V backend." OFF
)
# Top level target used to build all Libclc libraries.
add_custom_target( libclc ALL )
@ -115,14 +119,17 @@ foreach( tool IN ITEMS clang opt llvm-as llvm-link )
endif()
endforeach()
# llvm-spirv is an optional dependency, used to build spirv-* targets.
# It may be provided in-tree or externally.
if( TARGET llvm-spirv )
get_host_tool_path( llvm-spirv LLVM_SPIRV llvm-spirv_exe llvm-spirv_target )
else()
find_program( LLVM_SPIRV llvm-spirv HINTS ${LLVM_TOOLS_BINARY_DIR} )
set( llvm-spirv_exe "${LLVM_SPIRV}" )
set( llvm-spirv_target )
if( NOT LIBCLC_USE_SPIRV_BACKEND )
# llvm-spirv is an optional dependency, used to build spirv-* targets when
# the SPIR-V backend hasn't been requested. It may be provided in-tree or
# externally.
if( TARGET llvm-spirv )
get_host_tool_path( llvm-spirv LLVM_SPIRV llvm-spirv_exe llvm-spirv_target )
else()
find_program( LLVM_SPIRV llvm-spirv HINTS ${LLVM_TOOLS_BINARY_DIR} )
set( llvm-spirv_exe "${LLVM_SPIRV}" )
set( llvm-spirv_target )
endif()
endif()
# List of all targets. Note that some are added dynamically below.
@ -138,22 +145,24 @@ set( LIBCLC_TARGETS_ALL
nvptx64--nvidiacl
)
# mesa3d environment is only available since LLVM 4.0
# The mesa3d environment is only available since LLVM 4.0
if( LLVM_PACKAGE_VERSION VERSION_GREATER_EQUAL 4.0.0 )
list( APPEND LIBCLC_TARGETS_ALL amdgcn-mesa-mesa3d )
endif()
# spirv-mesa3d and spirv64-mesa3d targets can only be built with the (optional)
# llvm-spirv external tool.
if( llvm-spirv_exe )
list( APPEND LIBCLC_TARGETS_ALL spirv-mesa3d- spirv64-mesa3d- )
# The spirv-mesa3d and spirv64-mesa3d targets are optional and can be built
# with either the LLVM SPIR-V backend or the external llvm-spirv tool.
if( LIBCLC_USE_SPIRV_BACKEND OR llvm-spirv_exe )
list( APPEND LIBCLC_TARGETS_ALL spirv-mesa3d- spirv64-mesa3d- )
endif()
# Verify that the user hasn't requested mesa3d targets without an available
# llvm-spirv tool.
if( "spirv-mesa3d-" IN_LIST LIBCLC_TARGETS_TO_BUILD OR "spirv64-mesa3d-" IN_LIST LIBCLC_TARGETS_TO_BUILD )
if( NOT llvm-spirv_exe )
message( FATAL_ERROR "SPIR-V targets requested, but spirv-tools is not installed" )
if( spirv-mesa3d- IN_LIST LIBCLC_TARGETS_TO_BUILD
OR spirv64-mesa3d- IN_LIST LIBCLC_TARGETS_TO_BUILD )
if( NOT LIBCLC_USE_SPIRV_BACKEND AND NOT llvm-spirv_exe )
message( FATAL_ERROR "SPIR-V targets requested, but spirv-tools is not "
"installed and the SPIR-V backend has not been requested." )
endif()
endif()

25
libclc/cmake/modules/AddLibclc.cmake
View File

@ -164,7 +164,9 @@ function(get_libclc_device_info)
list( GET TRIPLE 0 ARCH )
# Some targets don't have a specific device architecture to target
if( ARG_DEVICE STREQUAL none OR ARCH STREQUAL spirv OR ARCH STREQUAL spirv64 )
if( ARG_DEVICE STREQUAL none
OR ((ARCH STREQUAL spirv OR ARCH STREQUAL spirv64)
AND NOT LIBCLC_USE_SPIRV_BACKEND) )
set( cpu )
set( arch_suffix "${ARG_TRIPLE}" )
else()
@ -182,7 +184,11 @@ function(get_libclc_device_info)
# Some libclc targets are not real clang triples: return their canonical
# triples.
if( ARCH STREQUAL spirv OR ARCH STREQUAL clspv )
if( ARCH STREQUAL spirv AND LIBCLC_USE_SPIRV_BACKEND )
set( ARG_TRIPLE "spirv32--" )
elseif( ARCH STREQUAL spirv64 AND LIBCLC_USE_SPIRV_BACKEND )
set( ARG_TRIPLE "spirv64--" )
elseif( ARCH STREQUAL spirv OR ARCH STREQUAL clspv )
set( ARG_TRIPLE "spir--" )
elseif( ARCH STREQUAL spirv64 OR ARCH STREQUAL clspv64 )
set( ARG_TRIPLE "spir64--" )
@ -363,10 +369,17 @@ function(add_libclc_builtin_set)
if( ARG_ARCH STREQUAL spirv OR ARG_ARCH STREQUAL spirv64 )
set( obj_suffix ${ARG_ARCH_SUFFIX}.spv )
set( libclc_builtins_lib ${LIBCLC_OUTPUT_LIBRARY_DIR}/${obj_suffix} )
add_custom_command( OUTPUT ${libclc_builtins_lib}
COMMAND ${llvm-spirv_exe} ${spvflags} -o ${libclc_builtins_lib} ${builtins_link_lib}
DEPENDS ${llvm-spirv_target} ${builtins_link_lib} ${builtins_link_lib_tgt}
)
if ( LIBCLC_USE_SPIRV_BACKEND )
add_custom_command( OUTPUT ${libclc_builtins_lib}
COMMAND ${clang_exe} --target=${ARG_TRIPLE} -x ir -o ${libclc_builtins_lib} ${builtins_link_lib}
DEPENDS ${clang_target} ${builtins_link_lib} ${builtins_link_lib_tgt}
)
else()
add_custom_command( OUTPUT ${libclc_builtins_lib}
COMMAND ${llvm-spirv_exe} ${spvflags} -o ${libclc_builtins_lib} ${builtins_link_lib}
DEPENDS ${llvm-spirv_target} ${builtins_link_lib} ${builtins_link_lib_tgt}
)
endif()
else()
# Non-SPIR-V targets add an extra step to optimize the bytecode
set( builtins_opt_lib_tgt builtins.opt.${ARG_ARCH_SUFFIX} )