llvm-polly,clang-polly: Add llvm/clang variants w/polly support (#55065)

* llvm: build w/polly in-tree, optionally

Don't enable by default yet, defer rebuilds.

* top-level: llvm-polly, clang-polly

* bit hacky re:overrides
* need to explicitly set cmake flags for clang to link in polly

pkgs/development/compilers/llvm/7/clang/default.nix

@@ -1,6 +1,7 @@
 { stdenv, fetch, cmake, libxml2, llvm, version, clang-tools-extra_src, python
 , fixDarwinDylibNames
 , enableManpages ? false
+, enablePolly ? false # TODO: get this info from llvm (passthru?)
 }:
 
 let
@@ -30,6 +31,9 @@ let
       "-DSPHINX_OUTPUT_MAN=ON"
       "-DSPHINX_OUTPUT_HTML=OFF"
       "-DSPHINX_WARNINGS_AS_ERRORS=OFF"
+    ] ++ stdenv.lib.optionals enablePolly [
+      "-DWITH_POLLY=ON"
+      "-DLINK_POLLY_INTO_TOOLS=ON"
     ];
 
     patches = [ ./purity.patch ];

pkgs/development/compilers/llvm/7/default.nix

@@ -29,10 +29,16 @@ let
   in {
 
     llvm = callPackage ./llvm.nix { };
+    llvm-polly = callPackage ./llvm.nix { enablePolly = true; };
 
     clang-unwrapped = callPackage ./clang {
       inherit clang-tools-extra_src;
     };
+    clang-polly-unwrapped = callPackage ./clang {
+      inherit clang-tools-extra_src;
+      llvm = tools.llvm-polly;
+      enablePolly = true;
+    };
 
     llvm-manpages = lowPrio (tools.llvm.override {
       enableManpages = true;

pkgs/development/compilers/llvm/7/llvm.nix

@@ -16,12 +16,14 @@
 , enableManpages ? false
 , enableSharedLibraries ? true
 , enablePFM ? !stdenv.isDarwin
+, enablePolly ? false
 }:
 
 let
   inherit (stdenv.lib) optional optionals optionalString;
 
   src = fetch "llvm" "16s196wqzdw4pmri15hadzqgdi926zln3an2viwyq0kini6zr3d3";
+  polly_src = fetch "polly" "0wgvayfilgb530bq51l7szxfb13l24nnrmyji2f6ncq95a24dw8v";
 
   # Used when creating a version-suffixed symlink of libLLVM.dylib
   shortVersion = with stdenv.lib;
@@ -34,6 +36,9 @@ in stdenv.mkDerivation (rec {
     unpackFile ${src}
     mv llvm-${version}* llvm
     sourceRoot=$PWD/llvm
+  '' + optionalString enablePolly ''
+    unpackFile ${polly_src}
+    mv polly-* $sourceRoot/tools/polly
   '';
 
   outputs = [ "out" "python" ]

pkgs/top-level/all-packages.nix

@@ -6684,6 +6684,8 @@ in
       useMacosReexportHack = true;
     };
   };
+  llvm-polly = llvmPackages_7.llvm-polly;
+  clang-polly = clang_7.override { cc = llvmPackages_7.clang-polly-unwrapped; };
 
   clang_7  = llvmPackages_7.clang;
   clang_6  = llvmPackages_6.clang;