Port -print-memderefs to NPM

There is lots of code duplication, but hopefully it won't matter soon.

Reviewed By: ychen

Differential Revision: https://reviews.llvm.org/D91683

include/llvm/Analysis/MemDerefPrinter.h

@@ -0,0 +1,24 @@
+//===- MemDerefPrinter.h - Printer for isDereferenceablePointer -----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_MEMDEREFPRINTER_H
+#define LLVM_ANALYSIS_MEMDEREFPRINTER_H
+
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+class MemDerefPrinterPass : public PassInfoMixin<MemDerefPrinterPass> {
+  raw_ostream &OS;
+
+public:
+  MemDerefPrinterPass(raw_ostream &OS) : OS(OS) {}
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
+};
+} // namespace llvm
+
+#endif // LLVM_ANALYSIS_MEMDEREFPRINTER_H

lib/Analysis/MemDerefPrinter.cpp

@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Analysis/MemDerefPrinter.h"
 #include "llvm/Analysis/Loads.h"
 #include "llvm/Analysis/Passes.h"
 #include "llvm/IR/DataLayout.h"
@@ -17,6 +18,7 @@
 #include "llvm/Pass.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/raw_ostream.h"
+
 using namespace llvm;
 
 namespace {
@@ -76,3 +78,35 @@ void MemDerefPrinter::print(raw_ostream &OS, const Module *M) const {
     OS << "\n\n";
   }
 }
+
+PreservedAnalyses MemDerefPrinterPass::run(Function &F,
+                                           FunctionAnalysisManager &AM) {
+  OS << "Memory Dereferencibility of pointers in function '" << F.getName()
+     << "'\n";
+
+  SmallVector<Value *, 4> Deref;
+  SmallPtrSet<Value *, 4> DerefAndAligned;
+
+  const DataLayout &DL = F.getParent()->getDataLayout();
+  for (auto &I : instructions(F)) {
+    if (LoadInst *LI = dyn_cast<LoadInst>(&I)) {
+      Value *PO = LI->getPointerOperand();
+      if (isDereferenceablePointer(PO, LI->getType(), DL))
+        Deref.push_back(PO);
+      if (isDereferenceableAndAlignedPointer(
+              PO, LI->getType(), MaybeAlign(LI->getAlignment()), DL))
+        DerefAndAligned.insert(PO);
+    }
+  }
+
+  OS << "The following are dereferenceable:\n";
+  for (Value *V : Deref) {
+    V->print(OS);
+    if (DerefAndAligned.count(V))
+      OS << "\t(aligned)";
+    else
+      OS << "\t(unaligned)";
+    OS << "\n\n";
+  }
+  return PreservedAnalyses::all();
+}

lib/Passes/PassBuilder.cpp

@@ -47,6 +47,7 @@
 #include "llvm/Analysis/LoopCacheAnalysis.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopNestAnalysis.h"
+#include "llvm/Analysis/MemDerefPrinter.h"
 #include "llvm/Analysis/MemoryDependenceAnalysis.h"
 #include "llvm/Analysis/MemorySSA.h"
 #include "llvm/Analysis/ModuleDebugInfoPrinter.h"

lib/Passes/PassRegistry.def

@@ -286,6 +286,7 @@ FUNCTION_PASS("print<stack-safety-local>", StackSafetyPrinterPass(dbgs()))
 FUNCTION_PASS("print-alias-sets", AliasSetsPrinterPass(dbgs()))
 FUNCTION_PASS("print-predicateinfo", PredicateInfoPrinterPass(dbgs()))
 FUNCTION_PASS("print-mustexecute", MustExecutePrinterPass(dbgs()))
+FUNCTION_PASS("print-memderefs", MemDerefPrinterPass(dbgs()))
 FUNCTION_PASS("reassociate", ReassociatePass())
 FUNCTION_PASS("redundant-dbg-inst-elim", RedundantDbgInstEliminationPass())
 FUNCTION_PASS("reg2mem", RegToMemPass())

test/Analysis/ValueTracking/memory-dereferenceable.ll

@@ -1,4 +1,5 @@
 ; RUN: opt -print-memderefs -analyze -S < %s -enable-new-pm=0 | FileCheck %s
+; RUN: opt -passes=print-memderefs -S < %s -disable-output 2>&1 | FileCheck %s
 
 ; Uses the print-deref (+ analyze to print) pass to run
 ; isDereferenceablePointer() on many load instruction operands