[PM] Port LoopInfo to the new pass manager, adding both a LoopAnalysis

pass and a LoopPrinterPass with the expected associated wiring.

I've added a RUN line to the only test case (!!!) we have that actually
prints loops. Everything seems to be working.

This is somewhat exciting as this is the first analysis using another
analysis to go in for the new pass manager. =D I also believe it is the
last analysis necessary for porting instcombine, but of course I may yet
discover more.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226560 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Analysis/LoopInfo.h b/include/llvm/Analysis/LoopInfo.h
index 0b78983380f49a61ab217cc4ee35da420f5b5b19..7811f24b86359e80d0f126c649aa6ce3b9a69261 100644 (file)
--- a/include/llvm/Analysis/LoopInfo.h
+++ b/include/llvm/Analysis/LoopInfo.h
@@ -42,6 +42,11 @@
 
 namespace llvm {
 
+// FIXME: Replace this brittle forward declaration with the include of the new
+// PassManager.h when doing so doesn't break the PassManagerBuilder.
+template <typename IRUnitT> class AnalysisManager;
+class PreservedAnalyses;
+
 template<typename T>
 inline void RemoveFromVector(std::vector<T*> &V, T *N) {
   typename std::vector<T*>::iterator I = std::find(V.begin(), V.end(), N);
@@ -716,6 +721,39 @@ template <> struct GraphTraits<Loop*> {
   }
 };
 
+/// \brief Analysis pass that exposes the \c LoopInfo for a function.
+class LoopAnalysis {
+  static char PassID;
+
+public:
+  typedef LoopInfo Result;
+
+  /// \brief Opaque, unique identifier for this analysis pass.
+  static void *ID() { return (void *)&PassID; }
+
+  /// \brief Provide a name for the analysis for debugging and logging.
+  static StringRef name() { return "LoopAnalysis"; }
+
+  LoopAnalysis() {}
+  LoopAnalysis(const LoopAnalysis &Arg) {}
+  LoopAnalysis(LoopAnalysis &&Arg) {}
+  LoopAnalysis &operator=(const LoopAnalysis &RHS) { return *this; }
+  LoopAnalysis &operator=(LoopAnalysis &&RHS) { return *this; }
+
+  LoopInfo run(Function &F, AnalysisManager<Function> *AM);
+};
+
+/// \brief Printer pass for the \c LoopAnalysis results.
+class LoopPrinterPass {
+  raw_ostream &OS;
+
+public:
+  explicit LoopPrinterPass(raw_ostream &OS) : OS(OS) {}
+  PreservedAnalyses run(Function &F, AnalysisManager<Function> *AM);
+
+  static StringRef name() { return "LoopPrinterPass"; }
+};
+
 /// \brief The legacy pass manager's analysis pass to compute loop information.
 class LoopInfoWrapperPass : public FunctionPass {
   LoopInfo LI;

diff --git a/lib/Analysis/LoopInfo.cpp b/lib/Analysis/LoopInfo.cpp
index 5fde485beca516faa01b9b66f91158b49fd965e4..95f6eb0af0f549b49c951b2e218da07871ff13f1 100644 (file)
--- a/lib/Analysis/LoopInfo.cpp
+++ b/lib/Analysis/LoopInfo.cpp
@@ -26,6 +26,7 @@
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Metadata.h"
+#include "llvm/IR/PassManager.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include <algorithm>
@@ -667,6 +668,26 @@ void LoopInfo::updateUnloop(Loop *Unloop) {
   }
 }
 
+char LoopAnalysis::PassID;
+
+LoopInfo LoopAnalysis::run(Function &F, AnalysisManager<Function> *AM) {
+  // FIXME: Currently we create a LoopInfo from scratch for every function.
+  // This may prove to be too wasteful due to deallocating and re-allocating
+  // memory each time for the underlying map and vector datastructures. At some
+  // point it may prove worthwhile to use a freelist and recycle LoopInfo
+  // objects. I don't want to add that kind of complexity until the scope of
+  // the problem is better understood.
+  LoopInfo LI;
+  LI.Analyze(AM->getResult<DominatorTreeAnalysis>(F));
+  return std::move(LI);
+}
+
+PreservedAnalyses LoopPrinterPass::run(Function &F,
+                                       AnalysisManager<Function> *AM) {
+  AM->getResult<LoopAnalysis>(F).print(OS);
+  return PreservedAnalyses::all();
+}
+
 //===----------------------------------------------------------------------===//
 // LoopInfo implementation
 //

diff --git a/test/Analysis/LoopInfo/2003-05-15-NestingProblem.ll b/test/Analysis/LoopInfo/2003-05-15-NestingProblem.ll
index a87bab7cabf234a950a59b259314d7a4f605b680..599b3e4b031125c45176c22d2c4059e5fcf9e040 100644 (file)
--- a/test/Analysis/LoopInfo/2003-05-15-NestingProblem.ll
+++ b/test/Analysis/LoopInfo/2003-05-15-NestingProblem.ll
@@ -2,6 +2,7 @@
 ; not a child of the loopentry.6 loop.
 ;
 ; RUN: opt < %s -analyze -loops | FileCheck %s
+; RUN: opt < %s -passes='print<loops>' -disable-output 2>&1 | FileCheck %s
 
 ; CHECK: Loop at depth 4 containing: %loopentry.7<header><latch><exiting>
 

diff --git a/tools/opt/PassRegistry.def b/tools/opt/PassRegistry.def
index 411ca0f02d8adae0cd45db539359870d06fa5d56..66ee5e56272096b57a671e712385b7409af120a8 100644 (file)
--- a/tools/opt/PassRegistry.def
+++ b/tools/opt/PassRegistry.def
@@ -51,6 +51,7 @@ CGSCC_PASS("no-op-cgscc", NoOpCGSCCPass())
 #define FUNCTION_ANALYSIS(NAME, CREATE_PASS)
 #endif
 FUNCTION_ANALYSIS("domtree", DominatorTreeAnalysis())
+FUNCTION_ANALYSIS("loops", LoopAnalysis())
 FUNCTION_ANALYSIS("no-op-function", NoOpFunctionAnalysis())
 #undef FUNCTION_ANALYSIS
 
@@ -61,6 +62,7 @@ FUNCTION_PASS("invalidate<all>", InvalidateAllAnalysesPass())
 FUNCTION_PASS("no-op-function", NoOpFunctionPass())
 FUNCTION_PASS("print", PrintFunctionPass(dbgs()))
 FUNCTION_PASS("print<domtree>", DominatorTreePrinterPass(dbgs()))
+FUNCTION_PASS("print<loops>", LoopPrinterPass(dbgs()))
 FUNCTION_PASS("verify", VerifierPass())
 FUNCTION_PASS("verify<domtree>", DominatorTreeVerifierPass())
 #undef FUNCTION_PASS

diff --git a/tools/opt/Passes.cpp b/tools/opt/Passes.cpp
index 1af4d52b8700d9d26832cbf44388a8e0e3cdc937..ee51543055474411d514810b0b766cf9bb582f95 100644 (file)
--- a/tools/opt/Passes.cpp
+++ b/tools/opt/Passes.cpp
@@ -17,6 +17,7 @@
 #include "Passes.h"
 #include "llvm/Analysis/CGSCCPassManager.h"
 #include "llvm/Analysis/LazyCallGraph.h"
+#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/IRPrintingPasses.h"