[llvm] [BOLT] Enable standalone build (PR #97130)

[Thorsten Schütt via llvm-commits]

================
@@ -4,6 +4,39 @@ set(LLVM_LINK_COMPONENTS
   AArch64Desc
   )
 
+if(BOLT_BUILT_STANDALONE)
+  # tablegen, copied from llvm/lib/Target/AAarch64/CMakeLists.txt
+  set(LLVM_TARGET_DEFINITIONS ${LLVM_MAIN_SRC_DIR}/lib/Target/AArch64/AArch64.td)
+  list(APPEND LLVM_TABLEGEN_FLAGS -I ${LLVM_MAIN_SRC_DIR}/lib/Target/AArch64)
+  tablegen(LLVM AArch64GenAsmMatcher.inc -gen-asm-matcher)
+  tablegen(LLVM AArch64GenAsmWriter.inc -gen-asm-writer)
+  tablegen(LLVM AArch64GenAsmWriter1.inc -gen-asm-writer -asmwriternum=1)
+  tablegen(LLVM AArch64GenCallingConv.inc -gen-callingconv)
+  tablegen(LLVM AArch64GenDAGISel.inc -gen-dag-isel)
+  tablegen(LLVM AArch64GenDisassemblerTables.inc -gen-disassembler)
+  tablegen(LLVM AArch64GenFastISel.inc -gen-fast-isel)
+  tablegen(LLVM AArch64GenGlobalISel.inc -gen-global-isel)
+  tablegen(LLVM AArch64GenO0PreLegalizeGICombiner.inc -gen-global-isel-combiner
----------------
tschuett wrote:

You can remove lines where -gen contains `global-isel' . All your potential code generation goes through the DAG.

https://github.com/llvm/llvm-project/pull/97130