Analysis: Move llvm::getConstantRangeFromMetadata to IR library.

[pcc]

Summary

We're about to start using it there.

[sanjoy]

lgtm with nits

llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp

18

Does this still need to include ValueTracking?

llvm/lib/Transforms/Scalar/GuardWidening.cpp

48

Does this still need to include ValueTracking?

[pcc]

llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp

18

It doesn't currently do so :)

llvm/lib/Transforms/Scalar/GuardWidening.cpp

48

Yes, we use (e.g.) isSafeToSpeculativelyExecute here.

llvm/include/llvm/Analysis/ValueTracking.h

 // computations have.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_ANALYSIS_VALUETRACKING_H
 #define LLVM_ANALYSIS_VALUETRACKING_H
 
 #include "llvm/IR/CallSite.h"
-#include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/Instruction.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/Support/DataTypes.h"
 
 namespace llvm {
 template <typename T> class ArrayRef;
   class APInt;
   class AddOperator;
matchSelectPattern(const Value *V, const Value *&LHS, const Value *&RHS,
     Value *L = const_cast<Value*>(LHS);
     Value *R = const_cast<Value*>(RHS);
     auto Result = matchSelectPattern(const_cast<Value*>(V), L, R);
     LHS = L;
     RHS = R;
     return Result;
   }
 
-  /// Parse out a conservative ConstantRange from !range metadata.
-  ///
-  /// E.g. if RangeMD is !{i32 0, i32 10, i32 15, i32 20} then return [0, 20).
-  ConstantRange getConstantRangeFromMetadata(const MDNode &RangeMD);
-
   /// Return true if RHS is known to be implied true by LHS.  Return false if
   /// RHS is known to be implied false by LHS.  Otherwise, return None if no
   /// implication can be made.
   /// A & B must be i1 (boolean) values or a vector of such values. Note that
   /// the truth table for implication is the same as <=u on i1 values (but not
   /// <=s!).  The truth table for both is:
   ///    | T | F (B)
   ///  T | T | F

llvm/include/llvm/IR/ConstantRange.h

 #define LLVM_IR_CONSTANTRANGE_H
 
 #include "llvm/ADT/APInt.h"
 #include "llvm/IR/InstrTypes.h"
 #include "llvm/Support/DataTypes.h"
 
 namespace llvm {
 
+class MDNode;
+
 /// This class represents a range of values.
 ///
 class ConstantRange {
   APInt Lower, Upper;
 
   // If we have move semantics, pass APInts by value and move them into place.
   typedef APInt APIntMoveTy;
 
public:
   void dump() const;
 };
 
 inline raw_ostream &operator<<(raw_ostream &OS, const ConstantRange &CR) {
   CR.print(OS);
   return OS;
 }
 
+/// Parse out a conservative ConstantRange from !range metadata.
+///
+/// E.g. if RangeMD is !{i32 0, i32 10, i32 15, i32 20} then return [0, 20).
+ConstantRange getConstantRangeFromMetadata(const MDNode &RangeMD);
+
 } // End llvm namespace
 
 #endif

llvm/lib/Analysis/ValueTracking.cpp

if (Value *C = lookThroughCast(CmpI, FalseVal, TrueVal, CastOp))
       return ::matchSelectPattern(Pred, FMF, CmpLHS, CmpRHS,
                                   C, cast<CastInst>(FalseVal)->getOperand(0),
                                   LHS, RHS);
   }
   return ::matchSelectPattern(Pred, FMF, CmpLHS, CmpRHS, TrueVal, FalseVal,
                               LHS, RHS);
 }
 
-ConstantRange llvm::getConstantRangeFromMetadata(const MDNode &Ranges) {
-  const unsigned NumRanges = Ranges.getNumOperands() / 2;
-  assert(NumRanges >= 1 && "Must have at least one range!");
-  assert(Ranges.getNumOperands() % 2 == 0 && "Must be a sequence of pairs");
-
-  auto *FirstLow = mdconst::extract<ConstantInt>(Ranges.getOperand(0));
-  auto *FirstHigh = mdconst::extract<ConstantInt>(Ranges.getOperand(1));
-
-  ConstantRange CR(FirstLow->getValue(), FirstHigh->getValue());
-
-  for (unsigned i = 1; i < NumRanges; ++i) {
-    auto *Low = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 0));
-    auto *High = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 1));
-
-    // Note: unionWith will potentially create a range that contains values not
-    // contained in any of the original N ranges.
-    CR = CR.unionWith(ConstantRange(Low->getValue(), High->getValue()));
-  }
-
-  return CR;
-}
-
 /// Return true if "icmp Pred LHS RHS" is always true.
 static bool isTruePredicate(CmpInst::Predicate Pred,
                             const Value *LHS, const Value *RHS,
                             const DataLayout &DL, unsigned Depth,
                             AssumptionCache *AC, const Instruction *CxtI,
                             const DominatorTree *DT) {
   assert(!LHS->getType()->isVectorTy() && "TODO: extend to handle vectors!");
   if (ICmpInst::isTrueWhenEqual(Pred) && LHS == RHS)

llvm/lib/IR/ConstantRange.cpp

else
     OS << "[" << Lower << "," << Upper << ")";
 }
 
 /// dump - Allow printing from a debugger easily...
 ///
 LLVM_DUMP_METHOD void ConstantRange::dump() const {
   print(dbgs());
 }
+
+ConstantRange llvm::getConstantRangeFromMetadata(const MDNode &Ranges) {
+  const unsigned NumRanges = Ranges.getNumOperands() / 2;
+  assert(NumRanges >= 1 && "Must have at least one range!");
+  assert(Ranges.getNumOperands() % 2 == 0 && "Must be a sequence of pairs");
+
+  auto *FirstLow = mdconst::extract<ConstantInt>(Ranges.getOperand(0));
+  auto *FirstHigh = mdconst::extract<ConstantInt>(Ranges.getOperand(1));
+
+  ConstantRange CR(FirstLow->getValue(), FirstHigh->getValue());
+
+  for (unsigned i = 1; i < NumRanges; ++i) {
+    auto *Low = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 0));
+    auto *High = mdconst::extract<ConstantInt>(Ranges.getOperand(2 * i + 1));
+
+    // Note: unionWith will potentially create a range that contains values not
+    // contained in any of the original N ranges.
+    CR = CR.unionWith(ConstantRange(Low->getValue(), High->getValue()));
+  }
+
+  return CR;
+}

llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp

 // This file implements the visit functions for load, store and alloca.
 //
 //===----------------------------------------------------------------------===//
 
 #include "InstCombineInternal.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/Loads.h"
+#include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/MDBuilder.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include "llvm/Transforms/Utils/Local.h"
 using namespace llvm;
 

llvm/lib/Transforms/Scalar/GuardWidening.cpp

 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Scalar/GuardWidening.h"
 #include "llvm/Pass.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/PostDominators.h"
 #include "llvm/Analysis/ValueTracking.h"
+#include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/PatternMatch.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Transforms/Scalar.h"
 
 using namespace llvm;