[PollyACC] Configure PollyPPCG only if needed.

The PollyPPCG library is only needed when POLLY_ENABLE_GPGPU_CODEGEN=ON.
If disabled, the library target is still created, but not linked against
anything.

This change does not add create the PollyPPCG build target if not
needed.

Motivated by llvm.org/PR50021

1 files changed, 100 insertions, 76 deletions

diff --git a/polly/lib/External/CMakeLists.txt b/polly/lib/External/CMakeLists.txt
index 8991094..e3a5683 100644
--- a/polly/lib/External/CMakeLists.txt
+++ b/polly/lib/External/CMakeLists.txt
@@ -1,3 +1,18 @@
+# Disable warnings for upstream projects.
+if (MSVC)
+  set(DISABLE_WARNING_FLAGS
+    -wd4018 # 'expression' : signed/unsigned mismatch
+    -wd4090 # 'operation' : different 'modifier' qualifiers
+    -wd4200 # nonstandard extension used: zero-sized array in struct/union
+    -wd4201 # nonstandard extension used: nameless struct/union
+    -wd4334 # 'operator': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
+    -wd4221 # nonstandard extension used : 'identifier' : cannot be initialized using address of automatic variable
+  )
+else ()
+  set(DISABLE_WARNING_FLAGS "-w")
+endif ()
+
+
 # External: Integer Set Library
 if (POLLY_BUNDLED_ISL)
   set(ISL_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/isl")
@@ -293,86 +308,95 @@ if (POLLY_BUNDLED_ISL)
 
   # ISL requires at least C99 to compile. gcc < 5.0 use -std=gnu89 as default.
   set_property(TARGET PollyISL polly-isl-test PROPERTY C_STANDARD 99)
+
+  target_compile_options(PollyISL PRIVATE ${DISABLE_WARNING_FLAGS})
+  target_compile_options(polly-isl-test PRIVATE ${DISABLE_WARNING_FLAGS})
 endif (POLLY_BUNDLED_ISL)
 
-set(PET_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/pet")
-set(PPCG_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ppcg")
-set(PPCG_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/ppcg")
-
-# Determine version of ppcg
-if (EXISTS "${PPCG_SOURCE_DIR}/GIT_HEAD_ID")
-  # The source comes from a 'make dist' archive
-  file(READ "${PPCG_SOURCE_DIR}/GIT_HEAD_ID" PPCG_GIT_HEAD_ID)
-  string(STRIP "${PPCG_GIT_HEAD_ID}" PPCG_GIT_HEAD_ID)
-elseif (EXISTS "${PPCG_SOURCE_DIR}/gitversion.h")
-  # The source directory is preconfigured
-  file(READ "${PPCG_SOURCE_DIR}/gitversion.h" GITVERSION_H)
-  string(REGEX REPLACE ".*\\\"([^\\\"]*)\\\".*" "\\1" PPCG_GIT_HEAD_ID "${GITVERSION_H}")
-elseif ()
-  # Unknown revision
-  # TODO: We could look for a .git and get the revision from HEAD
-  set(PPCG_GIT_HEAD_ID "UNKNOWN")
-endif ()
 
-message(STATUS "PPCG version: ${PPCG_GIT_HEAD_ID}")
-
-set (PPCG_FILES
-     ppcg/cuda.c
-     ppcg/cuda_common.c
-     ppcg/external.c
-     ppcg/gpu_array_tile.c
-     ppcg/gpu.c
-     ppcg/gpu_array_tile.c
-     ppcg/gpu_group.c
-     ppcg/gpu_hybrid.c
-     ppcg/gpu_print.c
-     ppcg/gpu_tree.c
-     ppcg/grouping.c
-     ppcg/hybrid.c
-     ppcg/ppcg.c
-     ppcg/ppcg_options.c
-     ppcg/print.c
-     ppcg/schedule.c
-     ppcg/util.c
-     )
-
-include_directories(BEFORE
-  ${PPCG_BINARY_DIR}
-  ${PPCG_SOURCE_DIR}/imath
-  ${PPCG_SOURCE_DIR}/include
-  ${PET_SOURCE_DIR}/include
-)
-
-add_polly_library(PollyPPCG
-  ${PPCG_FILES}
-)
-
-target_link_libraries(PollyPPCG PUBLIC ${ISL_TARGET})
+# External: Polyhedral Parallel Code Generator
+if (GPU_CODEGEN)
+  set(PET_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/pet")
+  set(PPCG_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ppcg")
+  set(PPCG_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/ppcg")
 
-# Disable warnings for upstream projects.
-if (MSVC)
-  set(DISABLE_WARNING_FLAGS
-    -wd4018 # 'expression' : signed/unsigned mismatch
-    -wd4090 # 'operation' : different 'modifier' qualifiers
-    -wd4200 # nonstandard extension used: zero-sized array in struct/union
-    -wd4201 # nonstandard extension used: nameless struct/union
-    -wd4334 # 'operator': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
-    -wd4221 # nonstandard extension used : 'identifier' : cannot be initialized using address of automatic variable
+  # Determine version of ppcg
+  if (EXISTS "${PPCG_SOURCE_DIR}/GIT_HEAD_ID")
+    # The source comes from a 'make dist' archive
+    file(READ "${PPCG_SOURCE_DIR}/GIT_HEAD_ID" PPCG_GIT_HEAD_ID)
+    string(STRIP "${PPCG_GIT_HEAD_ID}" PPCG_GIT_HEAD_ID)
+  elseif (EXISTS "${PPCG_SOURCE_DIR}/gitversion.h")
+    # The source directory is preconfigured
+    file(READ "${PPCG_SOURCE_DIR}/gitversion.h" GITVERSION_H)
+    string(REGEX REPLACE ".*\\\"([^\\\"]*)\\\".*" "\\1" PPCG_GIT_HEAD_ID "${GITVERSION_H}")
+  elseif ()
+    # Unknown revision
+    # TODO: We could look for a .git and get the revision from HEAD
+    set(PPCG_GIT_HEAD_ID "UNKNOWN")
+  endif ()
+
+  message(STATUS "PPCG version: ${PPCG_GIT_HEAD_ID}")
+
+  set (PPCG_FILES
+       ppcg/cuda.c
+       ppcg/cuda_common.c
+       ppcg/external.c
+       ppcg/gpu_array_tile.c
+       ppcg/gpu.c
+       ppcg/gpu_array_tile.c
+       ppcg/gpu_group.c
+       ppcg/gpu_hybrid.c
+       ppcg/gpu_print.c
+       ppcg/gpu_tree.c
+       ppcg/grouping.c
+       ppcg/hybrid.c
+       ppcg/ppcg.c
+       ppcg/ppcg_options.c
+       ppcg/print.c
+       ppcg/schedule.c
+       ppcg/util.c
+       )
+
+  include_directories(BEFORE
+    ${PPCG_BINARY_DIR}
+    ${PPCG_SOURCE_DIR}/imath
+    ${PPCG_SOURCE_DIR}/include
+    ${PET_SOURCE_DIR}/include
+  )
+
+  add_polly_library(PollyPPCG
+    ${PPCG_FILES}
   )
-  if (POLLY_BUNDLED_ISL)
-    target_compile_options(PollyISL PRIVATE ${DISABLE_WARNING_FLAGS})
-    target_compile_options(polly-isl-test PRIVATE ${DISABLE_WARNING_FLAGS})
-  endif (POLLY_BUNDLED_ISL)
-  target_compile_options(PollyPPCG PRIVATE ${DISABLE_WARNING_FLAGS})
-else ()
-  if (POLLY_BUNDLED_ISL)
-    set_target_properties(PollyISL polly-isl-test PROPERTIES COMPILE_FLAGS "-w")
-  endif (POLLY_BUNDLED_ISL)
-  set_target_properties(PollyPPCG PROPERTIES COMPILE_FLAGS "-w")
-endif ()
 
-if(MSVC)
-  # In the Windows API (with some exceptions), the maximum length for a path is
-  # MAX_PATH, which is defined as 260 characters.
-  target_compile_definitions(PollyPPCG PRIVATE "-DPATH_MAX=260")
+  target_link_libraries(PollyPPCG PUBLIC ${ISL_TARGET})
+
+  # Disable warnings for upstream projects.
+  if (MSVC)
+    set(DISABLE_WARNING_FLAGS
+      -wd4018 # 'expression' : signed/unsigned mismatch
+      -wd4090 # 'operation' : different 'modifier' qualifiers
+      -wd4200 # nonstandard extension used: zero-sized array in struct/union
+      -wd4201 # nonstandard extension used: nameless struct/union
+      -wd4334 # 'operator': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)
+      -wd4221 # nonstandard extension used : 'identifier' : cannot be initialized using address of automatic variable
+    )
+    if (POLLY_BUNDLED_ISL)
+      target_compile_options(PollyISL PRIVATE ${DISABLE_WARNING_FLAGS})
+      target_compile_options(polly-isl-test PRIVATE ${DISABLE_WARNING_FLAGS})
+    endif (POLLY_BUNDLED_ISL)
+    target_compile_options(PollyPPCG PRIVATE ${DISABLE_WARNING_FLAGS})
+  else ()
+    if (POLLY_BUNDLED_ISL)
+      set_target_properties(PollyISL polly-isl-test PROPERTIES COMPILE_FLAGS "-w")
+    endif (POLLY_BUNDLED_ISL)
+    set_target_properties(PollyPPCG PROPERTIES COMPILE_FLAGS "-w")
+  endif ()
+
+  if(MSVC)
+    # In the Windows API (with some exceptions), the maximum length for a path is
+    # MAX_PATH, which is defined as 260 characters.
+    target_compile_definitions(PollyPPCG PRIVATE "-DPATH_MAX=260")
+  endif ()
+
+  target_compile_options(PollyPPCG PRIVATE ${DISABLE_WARNING_FLAGS})
 endif ()