[NewPM] Remove LowerWidenableConditionLegacyPass (#72818)

This legacy pass isn't used anywhere upstream and thus has no test
coverage, so remove it.

Author: boomanaiden154

llvm/include/llvm/InitializePasses.h

@@ -185,7 +185,6 @@ void initializeLowerAtomicLegacyPassPass(PassRegistry&);
 void initializeLowerConstantIntrinsicsPass(PassRegistry&);
 void initializeLowerEmuTLSPass(PassRegistry&);
 void initializeLowerGlobalDtorsLegacyPassPass(PassRegistry &);
-void initializeLowerWidenableConditionLegacyPassPass(PassRegistry&);
 void initializeLowerIntrinsicsPass(PassRegistry&);
 void initializeLowerInvokeLegacyPassPass(PassRegistry&);
 void initializeLowerSwitchLegacyPassPass(PassRegistry &);

llvm/include/llvm/Transforms/Scalar.h

@@ -165,12 +165,6 @@ FunctionPass *createSinkingPass();
 //
 Pass *createLowerAtomicPass();
 
-//===----------------------------------------------------------------------===//
-//
-// LowerWidenableCondition - Lower widenable condition to i1 true.
-//
-Pass *createLowerWidenableConditionPass();
-
 //===----------------------------------------------------------------------===//
 //
 // MergeICmps - Merge integer comparison chains into a memcmp

llvm/lib/Transforms/Scalar/LowerWidenableCondition.cpp

@@ -19,24 +19,10 @@
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/PatternMatch.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Pass.h"
 #include "llvm/Transforms/Scalar.h"
 
 using namespace llvm;
 
-namespace {
-struct LowerWidenableConditionLegacyPass : public FunctionPass {
-  static char ID;
-  LowerWidenableConditionLegacyPass() : FunctionPass(ID) {
-    initializeLowerWidenableConditionLegacyPassPass(
-        *PassRegistry::getPassRegistry());
-  }
-
-  bool runOnFunction(Function &F) override;
-};
-}
-
 static bool lowerWidenableCondition(Function &F) {
   // Check if we can cheaply rule out the possibility of not having any work to
   // do.
@@ -65,19 +51,6 @@ static bool lowerWidenableCondition(Function &F) {
   return true;
 }
 
-bool LowerWidenableConditionLegacyPass::runOnFunction(Function &F) {
-  return lowerWidenableCondition(F);
-}
-
-char LowerWidenableConditionLegacyPass::ID = 0;
-INITIALIZE_PASS(LowerWidenableConditionLegacyPass, "lower-widenable-condition",
-                "Lower the widenable condition to default true value", false,
-                false)
-
-Pass *llvm::createLowerWidenableConditionPass() {
-  return new LowerWidenableConditionLegacyPass();
-}
-
 PreservedAnalyses LowerWidenableConditionPass::run(Function &F,
                                                FunctionAnalysisManager &AM) {
   if (lowerWidenableCondition(F))

llvm/lib/Transforms/Scalar/Scalar.cpp

@@ -38,7 +38,6 @@ void llvm::initializeScalarOpts(PassRegistry &Registry) {
   initializeLoopUnrollPass(Registry);
   initializeLowerAtomicLegacyPassPass(Registry);
   initializeLowerConstantIntrinsicsPass(Registry);
-  initializeLowerWidenableConditionLegacyPassPass(Registry);
   initializeMergeICmpsLegacyPassPass(Registry);
   initializeNaryReassociateLegacyPassPass(Registry);
   initializePartiallyInlineLibCallsLegacyPassPass(Registry);