[PM] Port ADCE to the new pass manager

llvm-svn: 251725

7 files changed, 76 insertions, 28 deletions

diff --git a/llvm/include/llvm/InitializePasses.h b/llvm/include/llvm/InitializePasses.h
index 3c2160292d5..7e572232d5b 100644
--- a/llvm/include/llvm/InitializePasses.h
+++ b/llvm/include/llvm/InitializePasses.h
@@ -61,7 +61,7 @@ void initializeTarget(PassRegistry&);
 
 void initializeAAEvalPass(PassRegistry&);
 void initializeAddDiscriminatorsPass(PassRegistry&);
-void initializeADCEPass(PassRegistry&);
+void initializeADCELegacyPassPass(PassRegistry&);
 void initializeBDCEPass(PassRegistry&);
 void initializeAliasSetPrinterPass(PassRegistry&);
 void initializeAlwaysInlinerPass(PassRegistry&);
diff --git a/llvm/include/llvm/Transforms/Scalar/ADCE.h b/llvm/include/llvm/Transforms/Scalar/ADCE.h
new file mode 100644
index 00000000000..f9bc7b77c14
--- /dev/null
+++ b/llvm/include/llvm/Transforms/Scalar/ADCE.h
@@ -0,0 +1,38 @@
+//===- ADCE.h - Aggressive dead code elimination --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the interface for the Aggressive Dead Code Elimination
+// pass. This pass optimistically assumes that all instructions are dead until
+// proven otherwise, allowing it to eliminate dead computations that other DCE
+// passes do not catch, particularly involving loop computations.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_SCALAR_ADCE_H
+#define LLVM_TRANSFORMS_SCALAR_ADCE_H
+
+#include "llvm/IR/Function.h"
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+
+/// A DCE pass that assumes instructions are dead until proven otherwise.
+///
+/// This pass eliminates dead code by optimistically assuming that all
+/// instructions are dead until proven otherwise. This allows it to eliminate
+/// dead computations that other DCE passes do not catch, particularly involving
+/// loop computations.
+class ADCEPass {
+public:
+  static StringRef name() { return "ADCEPass"; }
+  PreservedAnalyses run(Function &F);
+};
+}
+
+#endif // LLVM_TRANSFORMS_SCALAR_ADCE_H
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index b8f6e204a9c..f18fcb18575 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -30,6 +30,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Transforms/InstCombine/InstCombine.h"
+#include "llvm/Transforms/Scalar/ADCE.h"
 #include "llvm/Transforms/Scalar/EarlyCSE.h"
 #include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h"
 #include "llvm/Transforms/Scalar/SimplifyCFG.h"
diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def
index da4e63b1a16..6f523301f92 100644
--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -63,6 +63,7 @@ FUNCTION_ANALYSIS("targetir",
 #ifndef FUNCTION_PASS
 #define FUNCTION_PASS(NAME, CREATE_PASS)
 #endif
+FUNCTION_PASS("adce", ADCEPass())
 FUNCTION_PASS("early-cse", EarlyCSEPass())
 FUNCTION_PASS("instcombine", InstCombinePass())
 FUNCTION_PASS("invalidate<all>", InvalidateAllAnalysesPass())
diff --git a/llvm/lib/Transforms/Scalar/ADCE.cpp b/llvm/lib/Transforms/Scalar/ADCE.cpp
index c73766cc03a..590a52da6b1 100644
--- a/llvm/lib/Transforms/Scalar/ADCE.cpp
+++ b/llvm/lib/Transforms/Scalar/ADCE.cpp
@@ -14,7 +14,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Scalar/ADCE.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
@@ -26,35 +26,14 @@
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/Pass.h"
+#include "llvm/Transforms/Scalar.h"
 using namespace llvm;
 
 #define DEBUG_TYPE "adce"
 
 STATISTIC(NumRemoved, "Number of instructions removed");
 
-namespace {
-struct ADCE : public FunctionPass {
-  static char ID; // Pass identification, replacement for typeid
-  ADCE() : FunctionPass(ID) {
-    initializeADCEPass(*PassRegistry::getPassRegistry());
-  }
-
-  bool runOnFunction(Function& F) override;
-
-  void getAnalysisUsage(AnalysisUsage& AU) const override {
-    AU.setPreservesCFG();
-    AU.addPreserved<GlobalsAAWrapperPass>();
-  }
-};
-}
-
-char ADCE::ID = 0;
-INITIALIZE_PASS(ADCE, "adce", "Aggressive Dead Code Elimination", false, false)
-
-bool ADCE::runOnFunction(Function& F) {
-  if (skipOptnoneFunction(F))
-    return false;
-
+static bool aggressiveDCE(Function& F) {
   SmallPtrSet<Instruction*, 128> Alive;
   SmallVector<Instruction*, 128> Worklist;
 
@@ -96,6 +75,34 @@ bool ADCE::runOnFunction(Function& F) {
   return !Worklist.empty();
 }
 
-FunctionPass *llvm::createAggressiveDCEPass() {
-  return new ADCE();
+PreservedAnalyses ADCEPass::run(Function &F) {
+  if (aggressiveDCE(F))
+    return PreservedAnalyses::none();
+  return PreservedAnalyses::all();
 }
+
+namespace {
+struct ADCELegacyPass : public FunctionPass {
+  static char ID; // Pass identification, replacement for typeid
+  ADCELegacyPass() : FunctionPass(ID) {
+    initializeADCELegacyPassPass(*PassRegistry::getPassRegistry());
+  }
+
+  bool runOnFunction(Function& F) override {
+    if (skipOptnoneFunction(F))
+      return false;
+    return aggressiveDCE(F);
+  }
+
+  void getAnalysisUsage(AnalysisUsage& AU) const override {
+    AU.setPreservesCFG();
+    AU.addPreserved<GlobalsAAWrapperPass>();
+  }
+};
+}
+
+char ADCELegacyPass::ID = 0;
+INITIALIZE_PASS(ADCELegacyPass, "adce", "Aggressive Dead Code Elimination",
+                false, false)
+
+FunctionPass *llvm::createAggressiveDCEPass() { return new ADCELegacyPass(); }
diff --git a/llvm/lib/Transforms/Scalar/Scalar.cpp b/llvm/lib/Transforms/Scalar/Scalar.cpp
index f7a61343f4a..fd74fa84226 100644
--- a/llvm/lib/Transforms/Scalar/Scalar.cpp
+++ b/llvm/lib/Transforms/Scalar/Scalar.cpp
@@ -30,7 +30,7 @@ using namespace llvm;
 /// initializeScalarOptsPasses - Initialize all passes linked into the
 /// ScalarOpts library.
 void llvm::initializeScalarOpts(PassRegistry &Registry) {
-  initializeADCEPass(Registry);
+  initializeADCELegacyPassPass(Registry);
   initializeBDCEPass(Registry);
   initializeAlignmentFromAssumptionsPass(Registry);
   initializeConstantHoistingPass(Registry);
diff --git a/llvm/test/Transforms/ADCE/basictest.ll b/llvm/test/Transforms/ADCE/basictest.ll
index 61c4224df97..aaacc184225 100644
--- a/llvm/test/Transforms/ADCE/basictest.ll
+++ b/llvm/test/Transforms/ADCE/basictest.ll
@@ -1,4 +1,5 @@
 ; RUN: opt < %s -adce -simplifycfg | llvm-dis
+; RUN: opt < %s -passes=adce | llvm-dis
 
 define i32 @Test(i32 %A, i32 %B) {
 BB1: