[libc] Fix installing GPU headers

[jhuber6]

Summary

The patch in D152592 changed the logic for this. We could never check if
we were on the GPU as this was before the variable was defined so I
moved it later. Secondly, we cannot use the LLVM_BINARY_DIR here, and
I do not know if that works in general. The problem is that it will
isntall the headers under a normal path outside of the
LLVM_ENABLE_RUNTIMES build. I don't know if that's correct for the
other targets, but for the GPU I need to set it back to the
CMAKE_BINARY_DIR so it works.

[phosek]

libc/CMakeLists.txt

90

Should this also be changed to ${CMAKE_BINARY_DIR}/lib? I'd expect for either both LLVM_BINARY_DIR and LLVM_LIBRARY_OUTPUT_INTDIR to be defined, or neither.

[jhuber6]

libc/CMakeLists.txt

90

I think previously it was the one with the host triple, but it should probably just go under /lib since we call it libcgpu.a.

[jhuber6]

PUt the libcgpu.a and libmgpu.a in the binary directory.

[phosek]

LGTM

libc/CMakeLists.txt

 
 # The top-level source directory.
 set(LIBC_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 # The top-level directory in which libc is being built.
 set(LIBC_BUILD_DIR ${CMAKE_CURRENT_BINARY_DIR})
 
 set(LIBC_ENABLE_USE_BY_CLANG OFF CACHE BOOL "Whether or not to place libc in a build directory findable by a just built clang")
 
-if(LIBC_TARGET_ARCHITECTURE_IS_GPU)
-  set(LIBC_INCLUDE_DIR ${LLVM_BINARY_DIR}/include/gpu-none-llvm)
-  set(LIBC_INSTALL_INCLUDE_DIR ${CMAKE_INSTALL_INCLUDEDIR}/gpu-none-llvm)
-  set(LIBC_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/gnu-none-llvm)
-elseif(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND LIBC_ENABLE_USE_BY_CLANG)
-  set(LIBC_INCLUDE_DIR ${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE})
-  set(LIBC_INSTALL_INCLUDE_DIR ${CMAKE_INSTALL_INCLUDEDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
-  set(LIBC_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
-else()
-  if(NOT LIBC_ENABLE_USE_BY_CLANG)
-    set(LIBC_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/include)
-    set(LIBC_LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/lib)
-  elseif(LLVM_LIBRARY_OUTPUT_INTDIR)
-    set(LIBC_INCLUDE_DIR ${LLVM_BINARY_DIR}/include)
-    set(LIBC_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
-  else()
-    set(LIBC_INCLUDE_DIR ${CMAKE_BINARY_DIR}/include)
-    set(LIBC_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
-  endif()
-  set(LIBC_INSTALL_INCLUDE_DIR ${CMAKE_INSTALL_INCLUDEDIR})
-endif()
-
 if(LLVM_LIBC_FULL_BUILD OR LIBC_GPU_BUILD OR LIBC_GPU_ARCHITECTURES)
   if(NOT LIBC_HDRGEN_EXE)
     # We need to set up hdrgen first since other targets depend on it.
     add_subdirectory(utils/LibcTableGenUtil)
     add_subdirectory(utils/HdrGen)
   else()
     message(STATUS "Will use ${LIBC_HDRGEN_EXE} for libc header generation.")
   endif()

 
 set(LIBC_ENABLE_UNITTESTS ON)
 set(LIBC_ENABLE_HERMETIC_TESTS ${LLVM_LIBC_FULL_BUILD})
 
 # Defines LIBC_TARGET_ARCHITECTURE and associated macros.
 include(LLVMLibCArchitectures)
 
 if(LIBC_TARGET_ARCHITECTURE_IS_GPU)
+  set(LIBC_INCLUDE_DIR ${CMAKE_BINARY_DIR}/include/gpu-none-llvm)
+  set(LIBC_INSTALL_INCLUDE_DIR ${CMAKE_INSTALL_INCLUDEDIR}/gpu-none-llvm)
+  set(LIBC_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
+elseif(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND LIBC_ENABLE_USE_BY_CLANG)
+  set(LIBC_INCLUDE_DIR ${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE})
+  set(LIBC_INSTALL_INCLUDE_DIR ${CMAKE_INSTALL_INCLUDEDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
+  set(LIBC_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
+else()
+  if(NOT LIBC_ENABLE_USE_BY_CLANG)
+    set(LIBC_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/include)
+    set(LIBC_LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/lib)
+  elseif(LLVM_LIBRARY_OUTPUT_INTDIR)
+    set(LIBC_INCLUDE_DIR ${LLVM_BINARY_DIR}/include)
+    set(LIBC_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
+  else()
+    set(LIBC_INCLUDE_DIR ${CMAKE_BINARY_DIR}/include)
+    set(LIBC_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
+  endif()
+  set(LIBC_INSTALL_INCLUDE_DIR ${CMAKE_INSTALL_INCLUDEDIR})
+endif()
+
+if(LIBC_TARGET_ARCHITECTURE_IS_GPU)
   include(prepare_libc_gpu_build)
   set(LIBC_ENABLE_UNITTESTS OFF)
 endif()
 
 include(LLVMLibCCheckMPFR)
 
 if(LLVM_LIBC_CLANG_TIDY)
   set(LLVM_LIBC_ENABLE_LINTING ON)