[clang] [clang][AMDGPU] Enable module splitting by default (PR #128509)

[Joseph Huber via cfe-commits]

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@@ -1393,6 +1393,8 @@ def fhip_emit_relocatable : Flag<["-"], "fhip-emit-relocatable">,
   HelpText<"Compile HIP source to relocatable">;
 def fno_hip_emit_relocatable : Flag<["-"], "fno-hip-emit-relocatable">,
   HelpText<"Do not override toolchain to compile HIP source to relocatable">;
+def flto_partitions_EQ : Joined<["--"], "flto-partitions=">, Group<hip_Group>,
+  HelpText<"Number of partitions to use for parallel full LTO codegen. Use 1 to disable partitioning.">;
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jhuber6 wrote:

If we added a top level option for this it probably should've been made to work for non-AMDGPU uses.

https://github.com/llvm/llvm-project/pull/128509