Revert "Add a pass to collect dropped var stats for MIR (llvm#120780)"

This reverts commit 3bf91ad.
(llvmorg-20-init-16123-g3bf91ad2a9c7)

`llvm/CodeGen` should not depend on `llvm/Passes`.

Author: chapuni

llvm/include/llvm/CodeGen/DroppedVariableStatsMIR.h

@@ -18,7 +18,6 @@
 #ifndef LLVM_CODEGEN_MACHINEFUNCTIONPASS_H
 #define LLVM_CODEGEN_MACHINEFUNCTIONPASS_H
 
-#include "llvm/CodeGen/DroppedVariableStatsMIR.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/Pass.h"
 
@@ -68,7 +67,6 @@ class MachineFunctionPass : public FunctionPass {
   MachineFunctionProperties RequiredProperties;
   MachineFunctionProperties SetProperties;
   MachineFunctionProperties ClearedProperties;
-  DroppedVariableStatsMIR DroppedVarStatsMF;
 
   /// createPrinterPass - Get a machine function printer pass.
   Pass *createPrinterPass(raw_ostream &O,

llvm/include/llvm/CodeGen/MachineFunctionPass.h

@@ -50,7 +50,6 @@ add_llvm_component_library(LLVMCodeGen
   DeadMachineInstructionElim.cpp
   DetectDeadLanes.cpp
   DFAPacketizer.cpp
-  DroppedVariableStatsMIR.cpp
   DwarfEHPrepare.cpp
   EarlyIfConversion.cpp
   EdgeBundles.cpp

llvm/lib/CodeGen/CMakeLists.txt

@@ -32,11 +32,6 @@
 using namespace llvm;
 using namespace ore;
 
-static cl::opt<bool> DroppedVarStatsMIR(
-    "dropped-variable-stats-mir", cl::Hidden,
-    cl::desc("Dump dropped debug variables stats for MIR passes"),
-    cl::init(false));
-
 Pass *MachineFunctionPass::createPrinterPass(raw_ostream &O,
                                              const std::string &Banner) const {
   return createMachineFunctionPrinterPass(O, Banner);
@@ -96,15 +91,7 @@ bool MachineFunctionPass::runOnFunction(Function &F) {
 
   MFProps.reset(ClearedProperties);
 
-  bool RV;
-  if (DroppedVarStatsMIR) {
-    auto PassName = getPassName();
-    DroppedVarStatsMF.runBeforePass(PassName, &MF);
-    RV = runOnMachineFunction(MF);
-    DroppedVarStatsMF.runAfterPass(PassName, &MF);
-  } else {
-    RV = runOnMachineFunction(MF);
-  }
+  bool RV = runOnMachineFunction(MF);
 
   if (ShouldEmitSizeRemarks) {
     // We wanted size remarks. Check if there was a change to the number of

llvm/lib/CodeGen/DroppedVariableStatsMIR.cpp

@@ -27,7 +27,6 @@ add_llvm_unittest(CodeGenTests
   CCStateTest.cpp
   DIEHashTest.cpp
   DIETest.cpp
-  DroppedVariableStatsMIRTest.cpp
   DwarfStringPoolEntryRefTest.cpp
   InstrRefLDVTest.cpp
   LowLevelTypeTest.cpp