Remove dump CFG support from legacy pass manager

Upstream CFGPrinter support is being updated to remove legacy pass manager
support.

LGC only supports this option in legacy pass manager so removing the option
entirely. LGC now mostly uses the new pass manager, so the option is of limited
use and can only be enabled for backend passes anyway.

lgc/util/PassManager.cpp

@@ -51,10 +51,6 @@ namespace cl {
 // -verify-ir : verify the IR after each pass
 static cl::opt<bool> VerifyIr("verify-ir", cl::desc("Verify IR after each pass"), cl::init(false));
 
-// -dump-cfg-after : dump CFG as .dot files after specified pass
-static cl::opt<std::string> DumpCfgAfter("dump-cfg-after", cl::desc("Dump CFG as .dot files after specified pass"),
-                                         cl::init(""));
-
 // -dump-pass-name : dump executed pass name
 static cl::opt<bool> DumpPassName("dump-pass-name", cl::desc("Dump executed pass name"), cl::init(false));
 
@@ -92,7 +88,6 @@ class LegacyPassManagerImpl final : public lgc::LegacyPassManager {
 
 private:
   bool m_stopped = false;              // Whether we have already stopped adding new passes.
-  AnalysisID m_dumpCfgAfter = nullptr; // -dump-cfg-after pass id
   AnalysisID m_printModule = nullptr;  // Pass id of dump pass "Print Module IR"
   unsigned *m_passIndex = nullptr;     // Pass Index
 };
@@ -200,9 +195,6 @@ std::unique_ptr<lgc::MbPassManager> lgc::MbPassManager::Create(TargetMachine *ta
 
 // =====================================================================================================================
 LegacyPassManagerImpl::LegacyPassManagerImpl() : LegacyPassManager() {
-  if (!cl::DumpCfgAfter.empty())
-    m_dumpCfgAfter = getPassIdFromName(cl::DumpCfgAfter);
-
   m_printModule = getPassIdFromName("print-module");
 }
 
@@ -216,8 +208,6 @@ PassManagerImpl::PassManagerImpl(TargetMachine *targetMachine, LLVMContext &cont
 #endif
           cl::DebugPassManager, cl::DebugPassManager || cl::VerifyIr,
           /*PrintPassOpts=*/{true, false, true}) {
-  if (!cl::DumpCfgAfter.empty())
-    report_fatal_error("The --dump-cfg-after option is not supported with the new pass manager.");
 
   auto &options = cl::getRegisteredOptions();
 
@@ -238,9 +228,6 @@ MbPassManagerImpl::MbPassManagerImpl(TargetMachine *targetMachine)
     : MbPassManager(), m_targetMachine(targetMachine),
       m_instrumentationStandard(cl::DebugPassManager, cl::DebugPassManager || cl::VerifyIr,
                                 /*PrintPassOpts=*/{true, false, true}) {
-  if (!cl::DumpCfgAfter.empty())
-    report_fatal_error("The --dump-cfg-after option is not supported with the new pass manager.");
-
   auto &options = cl::getRegisteredOptions();
 
   auto it = options.find("stop-after");
@@ -410,11 +397,6 @@ void LegacyPassManagerImpl::add(Pass *pass) {
     // Add a verify pass after it.
     legacy::PassManager::add(createVerifierPass(true)); // FatalErrors=true
   }
-
-  if (passId == m_dumpCfgAfter) {
-    // Add a CFG printer pass after it.
-    legacy::PassManager::add(createCFGPrinterLegacyPassPass());
-  }
 }
 
 // =====================================================================================================================