Merge "Update prebuilt Clang to r353983." into p9.0HEADp9.0-backupp9.0

1 files changed, 345 insertions, 0 deletions

diff --git a/clang-r353983/include/llvm/IR/ConstantRange.h b/clang-r353983/include/llvm/IR/ConstantRange.h
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+//===- ConstantRange.h - Represent a range ----------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Represent a range of possible values that may occur when the program is run
+// for an integral value.  This keeps track of a lower and upper bound for the
+// constant, which MAY wrap around the end of the numeric range.  To do this, it
+// keeps track of a [lower, upper) bound, which specifies an interval just like
+// STL iterators.  When used with boolean values, the following are important
+// ranges: :
+//
+//  [F, F) = {}     = Empty set
+//  [T, F) = {T}
+//  [F, T) = {F}
+//  [T, T) = {F, T} = Full set
+//
+// The other integral ranges use min/max values for special range values. For
+// example, for 8-bit types, it uses:
+// [0, 0)     = {}       = Empty set
+// [255, 255) = {0..255} = Full Set
+//
+// Note that ConstantRange can be used to represent either signed or
+// unsigned ranges.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_IR_CONSTANTRANGE_H
+#define LLVM_IR_CONSTANTRANGE_H
+
+#include "llvm/ADT/APInt.h"
+#include "llvm/IR/InstrTypes.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/Support/Compiler.h"
+#include <cstdint>
+
+namespace llvm {
+
+class MDNode;
+class raw_ostream;
+
+/// This class represents a range of values.
+class LLVM_NODISCARD ConstantRange {
+  APInt Lower, Upper;
+
+public:
+  /// Initialize a full (the default) or empty set for the specified bit width.
+  explicit ConstantRange(uint32_t BitWidth, bool isFullSet = true);
+
+  /// Initialize a range to hold the single specified value.
+  ConstantRange(APInt Value);
+
+  /// Initialize a range of values explicitly. This will assert out if
+  /// Lower==Upper and Lower != Min or Max value for its type. It will also
+  /// assert out if the two APInt's are not the same bit width.
+  ConstantRange(APInt Lower, APInt Upper);
+
+  /// Produce the smallest range such that all values that may satisfy the given
+  /// predicate with any value contained within Other is contained in the
+  /// returned range.  Formally, this returns a superset of
+  /// 'union over all y in Other . { x : icmp op x y is true }'.  If the exact
+  /// answer is not representable as a ConstantRange, the return value will be a
+  /// proper superset of the above.
+  ///
+  /// Example: Pred = ult and Other = i8 [2, 5) returns Result = [0, 4)
+  static ConstantRange makeAllowedICmpRegion(CmpInst::Predicate Pred,
+                                             const ConstantRange &Other);
+
+  /// Produce the largest range such that all values in the returned range
+  /// satisfy the given predicate with all values contained within Other.
+  /// Formally, this returns a subset of
+  /// 'intersection over all y in Other . { x : icmp op x y is true }'.  If the
+  /// exact answer is not representable as a ConstantRange, the return value
+  /// will be a proper subset of the above.
+  ///
+  /// Example: Pred = ult and Other = i8 [2, 5) returns [0, 2)
+  static ConstantRange makeSatisfyingICmpRegion(CmpInst::Predicate Pred,
+                                                const ConstantRange &Other);
+
+  /// Produce the exact range such that all values in the returned range satisfy
+  /// the given predicate with any value contained within Other. Formally, this
+  /// returns the exact answer when the superset of 'union over all y in Other
+  /// is exactly same as the subset of intersection over all y in Other.
+  /// { x : icmp op x y is true}'.
+  ///
+  /// Example: Pred = ult and Other = i8 3 returns [0, 3)
+  static ConstantRange makeExactICmpRegion(CmpInst::Predicate Pred,
+                                           const APInt &Other);
+
+  /// Return the largest range containing all X such that "X BinOpC Y" is
+  /// guaranteed not to wrap (overflow) for all Y in Other.
+  ///
+  /// NB! The returned set does *not* contain **all** possible values of X for
+  /// which "X BinOpC Y" does not wrap -- some viable values of X may be
+  /// missing, so you cannot use this to constrain X's range.  E.g. in the
+  /// fourth example, "(-2) + 1" is both nsw and nuw (so the "X" could be -2),
+  /// but (-2) is not in the set returned.
+  ///
+  /// Examples:
+  ///  typedef OverflowingBinaryOperator OBO;
+  ///  #define MGNR makeGuaranteedNoWrapRegion
+  ///  MGNR(Add, [i8 1, 2), OBO::NoSignedWrap) == [-128, 127)
+  ///  MGNR(Add, [i8 1, 2), OBO::NoUnsignedWrap) == [0, -1)
+  ///  MGNR(Add, [i8 0, 1), OBO::NoUnsignedWrap) == Full Set
+  ///  MGNR(Add, [i8 1, 2), OBO::NoUnsignedWrap | OBO::NoSignedWrap)
+  ///    == [0,INT_MAX)
+  ///  MGNR(Add, [i8 -1, 6), OBO::NoSignedWrap) == [INT_MIN+1, INT_MAX-4)
+  ///  MGNR(Sub, [i8 1, 2), OBO::NoSignedWrap) == [-127, 128)
+  ///  MGNR(Sub, [i8 1, 2), OBO::NoUnsignedWrap) == [1, 0)
+  ///  MGNR(Sub, [i8 1, 2), OBO::NoUnsignedWrap | OBO::NoSignedWrap)
+  ///    == [1,INT_MAX)
+  static ConstantRange makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
+                                                  const ConstantRange &Other,
+                                                  unsigned NoWrapKind);
+
+  /// Set up \p Pred and \p RHS such that
+  /// ConstantRange::makeExactICmpRegion(Pred, RHS) == *this.  Return true if
+  /// successful.
+  bool getEquivalentICmp(CmpInst::Predicate &Pred, APInt &RHS) const;
+
+  /// Return the lower value for this range.
+  const APInt &getLower() const { return Lower; }
+
+  /// Return the upper value for this range.
+  const APInt &getUpper() const { return Upper; }
+
+  /// Get the bit width of this ConstantRange.
+  uint32_t getBitWidth() const { return Lower.getBitWidth(); }
+
+  /// Return true if this set contains all of the elements possible
+  /// for this data-type.
+  bool isFullSet() const;
+
+  /// Return true if this set contains no members.
+  bool isEmptySet() const;
+
+  /// Return true if this set wraps around the top of the range.
+  /// For example: [100, 8).
+  bool isWrappedSet() const;
+
+  /// Return true if this set wraps around the INT_MIN of
+  /// its bitwidth. For example: i8 [120, 140).
+  bool isSignWrappedSet() const;
+
+  /// Return true if the specified value is in the set.
+  bool contains(const APInt &Val) const;
+
+  /// Return true if the other range is a subset of this one.
+  bool contains(const ConstantRange &CR) const;
+
+  /// If this set contains a single element, return it, otherwise return null.
+  const APInt *getSingleElement() const {
+    if (Upper == Lower + 1)
+      return &Lower;
+    return nullptr;
+  }
+
+  /// If this set contains all but a single element, return it, otherwise return
+  /// null.
+  const APInt *getSingleMissingElement() const {
+    if (Lower == Upper + 1)
+      return &Upper;
+    return nullptr;
+  }
+
+  /// Return true if this set contains exactly one member.
+  bool isSingleElement() const { return getSingleElement() != nullptr; }
+
+  /// Return the number of elements in this set.
+  APInt getSetSize() const;
+
+  /// Compare set size of this range with the range CR.
+  bool isSizeStrictlySmallerThan(const ConstantRange &CR) const;
+
+  // Compare set size of this range with Value.
+  bool isSizeLargerThan(uint64_t MaxSize) const;
+
+  /// Return the largest unsigned value contained in the ConstantRange.
+  APInt getUnsignedMax() const;
+
+  /// Return the smallest unsigned value contained in the ConstantRange.
+  APInt getUnsignedMin() const;
+
+  /// Return the largest signed value contained in the ConstantRange.
+  APInt getSignedMax() const;
+
+  /// Return the smallest signed value contained in the ConstantRange.
+  APInt getSignedMin() const;
+
+  /// Return true if this range is equal to another range.
+  bool operator==(const ConstantRange &CR) const {
+    return Lower == CR.Lower && Upper == CR.Upper;
+  }
+  bool operator!=(const ConstantRange &CR) const {
+    return !operator==(CR);
+  }
+
+  /// Subtract the specified constant from the endpoints of this constant range.
+  ConstantRange subtract(const APInt &CI) const;
+
+  /// Subtract the specified range from this range (aka relative complement of
+  /// the sets).
+  ConstantRange difference(const ConstantRange &CR) const;
+
+  /// Return the range that results from the intersection of
+  /// this range with another range.  The resultant range is guaranteed to
+  /// include all elements contained in both input ranges, and to have the
+  /// smallest possible set size that does so.  Because there may be two
+  /// intersections with the same set size, A.intersectWith(B) might not
+  /// be equal to B.intersectWith(A).
+  ConstantRange intersectWith(const ConstantRange &CR) const;
+
+  /// Return the range that results from the union of this range
+  /// with another range.  The resultant range is guaranteed to include the
+  /// elements of both sets, but may contain more.  For example, [3, 9) union
+  /// [12,15) is [3, 15), which includes 9, 10, and 11, which were not included
+  /// in either set before.
+  ConstantRange unionWith(const ConstantRange &CR) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from an application of the specified cast operator to this range. \p
+  /// BitWidth is the target bitwidth of the cast.  For casts which don't
+  /// change bitwidth, it must be the same as the source bitwidth.  For casts
+  /// which do change bitwidth, the bitwidth must be consistent with the
+  /// requested cast and source bitwidth.
+  ConstantRange castOp(Instruction::CastOps CastOp,
+                       uint32_t BitWidth) const;
+
+  /// Return a new range in the specified integer type, which must
+  /// be strictly larger than the current type.  The returned range will
+  /// correspond to the possible range of values if the source range had been
+  /// zero extended to BitWidth.
+  ConstantRange zeroExtend(uint32_t BitWidth) const;
+
+  /// Return a new range in the specified integer type, which must
+  /// be strictly larger than the current type.  The returned range will
+  /// correspond to the possible range of values if the source range had been
+  /// sign extended to BitWidth.
+  ConstantRange signExtend(uint32_t BitWidth) const;
+
+  /// Return a new range in the specified integer type, which must be
+  /// strictly smaller than the current type.  The returned range will
+  /// correspond to the possible range of values if the source range had been
+  /// truncated to the specified type.
+  ConstantRange truncate(uint32_t BitWidth) const;
+
+  /// Make this range have the bit width given by \p BitWidth. The
+  /// value is zero extended, truncated, or left alone to make it that width.
+  ConstantRange zextOrTrunc(uint32_t BitWidth) const;
+
+  /// Make this range have the bit width given by \p BitWidth. The
+  /// value is sign extended, truncated, or left alone to make it that width.
+  ConstantRange sextOrTrunc(uint32_t BitWidth) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from an application of the specified binary operator to an left hand side
+  /// of this range and a right hand side of \p Other.
+  ConstantRange binaryOp(Instruction::BinaryOps BinOp,
+                         const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from an addition of a value in this range and a value in \p Other.
+  ConstantRange add(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting from a
+  /// known NSW addition of a value in this range and \p Other constant.
+  ConstantRange addWithNoSignedWrap(const APInt &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a subtraction of a value in this range and a value in \p Other.
+  ConstantRange sub(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a multiplication of a value in this range and a value in \p Other,
+  /// treating both this and \p Other as unsigned ranges.
+  ConstantRange multiply(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a signed maximum of a value in this range and a value in \p Other.
+  ConstantRange smax(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from an unsigned maximum of a value in this range and a value in \p Other.
+  ConstantRange umax(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a signed minimum of a value in this range and a value in \p Other.
+  ConstantRange smin(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from an unsigned minimum of a value in this range and a value in \p Other.
+  ConstantRange umin(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from an unsigned division of a value in this range and a value in
+  /// \p Other.
+  ConstantRange udiv(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a binary-and of a value in this range by a value in \p Other.
+  ConstantRange binaryAnd(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a binary-or of a value in this range by a value in \p Other.
+  ConstantRange binaryOr(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting
+  /// from a left shift of a value in this range by a value in \p Other.
+  /// TODO: This isn't fully implemented yet.
+  ConstantRange shl(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting from a
+  /// logical right shift of a value in this range and a value in \p Other.
+  ConstantRange lshr(const ConstantRange &Other) const;
+
+  /// Return a new range representing the possible values resulting from a
+  /// arithmetic right shift of a value in this range and a value in \p Other.
+  ConstantRange ashr(const ConstantRange &Other) const;
+
+  /// Return a new range that is the logical not of the current set.
+  ConstantRange inverse() const;
+
+  /// Print out the bounds to a stream.
+  void print(raw_ostream &OS) const;
+
+  /// Allow printing from a debugger easily.
+  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 namespace llvm
+
+#endif // LLVM_IR_CONSTANTRANGE_H