gnu: Add fbgemm.

* gnu/packages/machine-learning.scm (fbgemm): New variable.
* gnu/packages/patches/fbgemm-use-system-libraries.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.

gnu/local.mk

@@ -1202,6 +1202,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/fasthenry-spUtils.patch			\
   %D%/packages/patches/fasthenry-spSolve.patch			\
   %D%/packages/patches/fasthenry-spFactor.patch			\
+  %D%/packages/patches/fbgemm-use-system-libraries.patch	\
   %D%/packages/patches/fbreader-curl-7.62.patch		\
   %D%/packages/patches/fbreader-fix-icon.patch		\
   %D%/packages/patches/feedbackd-use-system-gmobile.patch	\

gnu/packages/machine-learning.scm

@@ -4115,6 +4115,40 @@ (define-public xnnpack-for-torch2
                                  "-DXNNPACK_BUILD_TESTS=FALSE" ;FIXME: see below
                                  "-DXNNPACK_BUILD_BENCHMARKS=FALSE"))))))
 
+;; Warning: This package requires AVX2 or AVX-512 instructions.
+(define-public fbgemm
+  (package
+    (name "fbgemm")
+    (version "0.6.0")
+    (source (origin
+              (method git-fetch)
+              (uri (git-reference
+                    (url "https://github.com/pytorch/fbgemm")
+                    (commit (string-append "v" version))))
+              (file-name (git-file-name name version))
+              (sha256
+               (base32
+                "0mw30v55aicqdbh3xwfj9p8f38nw70ks5cxiwpgwjsk0dylah9rf"))
+              (patches (search-patches "fbgemm-use-system-libraries.patch"))
+              (modules '((guix build utils)))
+              (snippet
+               '(delete-file-recursively "third_party"))))
+    (build-system cmake-build-system)
+    (arguments
+     (list
+      #:configure-flags
+      ''("-DFBGEMM_LIBRARY_TYPE=shared")
+      ;; Tests require AVX2 or AVX-512 instructions
+      #:tests? #f))
+    (inputs (list asmjit cpuinfo))
+    (native-inputs (list pkg-config python googletest))
+    (home-page "https://github.com/pytorch/fbgemm")
+    (synopsis "Facebook GEneral Matrix Multiplication")
+    (description "Low-precision, high-performance matrix-matrix
+multiplications and convolution library for server-side inference.")
+    (supported-systems '("x86_64-linux"))
+    (license license:bsd-3)))
+
 (define-public tensorpipe
   (let ((commit "bb1473a4b38b18268e8693044afdb8635bc8351b")
         (revision "0"))

gnu/packages/patches/fbgemm-use-system-libraries.patch

@@ -0,0 +1,62 @@
+Use the asmjit and cpuinfo packages.
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 134523e..b88b0e7 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -235,7 +235,7 @@ message(WARNING "CMAKE_CXX_FLAGS_DEBUG is ${CMAKE_CXX_FLAGS_DEBUG}")
+ message(WARNING "CMAKE_CXX_FLAGS_RELEASE is ${CMAKE_CXX_FLAGS_RELEASE}")
+ message(WARNING "==========")
+ 
+-if(NOT TARGET asmjit)
++if(FALSE)
+   #Download asmjit from github if ASMJIT_SRC_DIR is not specified.
+   if(NOT DEFINED ASMJIT_SRC_DIR)
+     set(ASMJIT_SRC_DIR "${FBGEMM_SOURCE_DIR}/third_party/asmjit"
+@@ -264,7 +264,7 @@ if(NOT TARGET asmjit)
+   endif()
+ endif()
+ 
+-if(NOT TARGET cpuinfo)
++if(FALSE)
+   #Download cpuinfo from github if CPUINFO_SOURCE_DIR is not specified.
+   if(NOT DEFINED CPUINFO_SOURCE_DIR)
+     set(CPUINFO_SOURCE_DIR "${FBGEMM_SOURCE_DIR}/third_party/cpuinfo"
+@@ -340,9 +340,12 @@ target_include_directories(fbgemm BEFORE
+ target_link_libraries(fbgemm
+   $<BUILD_INTERFACE:asmjit>
+   $<BUILD_INTERFACE:cpuinfo>)
+-add_dependencies(fbgemm
+-  asmjit
+-  cpuinfo)
++
++find_package(asmjit)
++find_package(PkgConfig REQUIRED)
++pkg_check_modules(libcpuinfo REQUIRED IMPORTED_TARGET libcpuinfo)
++
++target_link_libraries(fbgemm asmjit::asmjit PkgConfig::libcpuinfo)
+ 
+ if(OpenMP_FOUND)
+   target_link_libraries(fbgemm OpenMP::OpenMP_CXX)
+diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
+index 2cffddf..bd4d409 100644
+--- a/test/CMakeLists.txt
++++ b/test/CMakeLists.txt
+@@ -14,7 +14,7 @@ set(CMAKE_C_STANDARD 11)
+ set(CMAKE_C_EXTENSIONS OFF)
+ set(CMAKE_C_STANDARD_REQUIRED ON)
+ 
+-if(FBGEMM_BUILD_TESTS AND NOT TARGET gtest)
++if(FALSE)
+   #Download Googletest framework from github if
+   #GOOGLETEST_SOURCE_DIR is not specified.
+   if(NOT DEFINED GOOGLETEST_SOURCE_DIR)
+@@ -78,7 +78,7 @@ macro(add_gtest TESTNAME)
+     target_link_libraries(${TESTNAME} ${OpenMP_CXX_LIBRARIES})
+   endif()
+ 
+-  add_dependencies(${TESTNAME} gtest fbgemm)
++  add_dependencies(${TESTNAME} fbgemm)
+   add_test(${TESTNAME} ${TESTNAME})
+   set_target_properties(${TESTNAME} PROPERTIES FOLDER test)
+ endmacro()