Revert "[AMDGPU] Add AMDGPU-specific module splitting" (#93275)

Fails on https://lab.llvm.org/buildbot/#/builders/85/builds/24181
and https://lab.llvm.org/buildbot/#/builders/5/builds/43589

Reverts #89245

Author: vitalybuka

llvm/lib/Target/AMDGPU/AMDGPUSplitModule.cpp

@@ -21,7 +21,6 @@
 #include "AMDGPUIGroupLP.h"
 #include "AMDGPUMacroFusion.h"
 #include "AMDGPURegBankSelect.h"
-#include "AMDGPUSplitModule.h"
 #include "AMDGPUTargetObjectFile.h"
 #include "AMDGPUTargetTransformInfo.h"
 #include "AMDGPUUnifyDivergentExitNodes.h"
@@ -816,13 +815,6 @@ AMDGPUTargetMachine::getAddressSpaceForPseudoSourceKind(unsigned Kind) const {
   return AMDGPUAS::FLAT_ADDRESS;
 }
 
-bool AMDGPUTargetMachine::splitModule(
-    Module &M, unsigned NumParts,
-    function_ref<void(std::unique_ptr<Module> MPart)> ModuleCallback) const {
-  splitAMDGPUModule(*this, M, NumParts, ModuleCallback);
-  return true;
-}
-
 //===----------------------------------------------------------------------===//
 // GCN Target Machine (SI+)
 //===----------------------------------------------------------------------===//

llvm/lib/Target/AMDGPU/AMDGPUSplitModule.h

@@ -73,10 +73,6 @@ class AMDGPUTargetMachine : public LLVMTargetMachine {
   getPredicatedAddrSpace(const Value *V) const override;
 
   unsigned getAddressSpaceForPseudoSourceKind(unsigned Kind) const override;
-
-  bool splitModule(Module &M, unsigned NumParts,
-                   function_ref<void(std::unique_ptr<Module> MPart)>
-                       ModuleCallback) const override;
 };
 
 //===----------------------------------------------------------------------===//

llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp

@@ -98,7 +98,6 @@ add_llvm_target(AMDGPUCodeGen
   AMDGPURewriteOutArguments.cpp
   AMDGPURewriteUndefForPHI.cpp
   AMDGPUSetWavePriority.cpp
-  AMDGPUSplitModule.cpp
   AMDGPUSubtarget.cpp
   AMDGPUTargetMachine.cpp
   AMDGPUTargetObjectFile.cpp