Revert "[CodeGen] Port SafeStack to new pass manager (#73747)" (#73965)

This reverts commit a4d5fd4d2ee9470e55345a9540f6b6fb6faf66e1.

The above commit breaks greendragon lldb bots:
Link to failing builds:
https://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/63300/
https://green.lab.llvm.org/green/view/LLDB/job/as-lldb-cmake/10345/

I found this PR to be the offending one after using git bisect with the
cmake invocation:

cmake -G Ninja ../llvm -DCMAKE_BUILD_TYPE=Release
-DCMAKE_EXPORT_COMPILE_COMMANDS=ON
'-DLLVM_TARGETS_TO_BUILD=X86;ARM;AArch64'
-DLLVM_ENABLE_ASSERTIONS:BOOL=TRUE
-DLLVM_ENABLE_MODULES=On
-DLLVM_ENABLE_PROJECTS='clang;lld;lldb;cross-project-tests'
-DLLVM_VERSION_PATCH=99
'-DLLVM_ENABLE_RUNTIMES=libcxx;libcxxabi;compiler-rt'

and running
ninja lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/CodeGenPassBuilder.cpp.o

1 files changed, 0 insertions, 37 deletions

diff --git a/llvm/lib/CodeGen/SafeStack.cpp b/llvm/lib/CodeGen/SafeStack.cpp
index 88db57a..ef293fa 100644
--- a/llvm/lib/CodeGen/SafeStack.cpp
+++ b/llvm/lib/CodeGen/SafeStack.cpp
@@ -14,7 +14,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/CodeGen/SafeStack.h"
 #include "SafeStackLayout.h"
 #include "llvm/ADT/APInt.h"
 #include "llvm/ADT/ArrayRef.h"
@@ -928,42 +927,6 @@ public:
 
 } // end anonymous namespace
 
-PreservedAnalyses SafeStackPass::run(Function &F,
-                                     FunctionAnalysisManager &FAM) {
-  LLVM_DEBUG(dbgs() << "[SafeStack] Function: " << F.getName() << "\n");
-
-  if (!F.hasFnAttribute(Attribute::SafeStack)) {
-    LLVM_DEBUG(dbgs() << "[SafeStack]     safestack is not requested"
-                         " for this function\n");
-    return PreservedAnalyses::all();
-  }
-
-  if (F.isDeclaration()) {
-    LLVM_DEBUG(dbgs() << "[SafeStack]     function definition"
-                         " is not available\n");
-    return PreservedAnalyses::all();
-  }
-
-  auto *TL = TM->getSubtargetImpl(F)->getTargetLowering();
-  if (!TL)
-    report_fatal_error("TargetLowering instance is required");
-
-  auto &DL = F.getParent()->getDataLayout();
-
-  // preserve DominatorTree
-  auto &DT = FAM.getResult<DominatorTreeAnalysis>(F);
-  auto &SE = FAM.getResult<ScalarEvolutionAnalysis>(F);
-  DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Lazy);
-
-  bool Changed = SafeStack(F, *TL, DL, &DTU, SE).run();
-
-  if (!Changed)
-    return PreservedAnalyses::all();
-  PreservedAnalyses PA;
-  PA.preserve<DominatorTreeAnalysis>();
-  return PA;
-}
-
 char SafeStackLegacyPass::ID = 0;
 
 INITIALIZE_PASS_BEGIN(SafeStackLegacyPass, DEBUG_TYPE,