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authorReid Spencer <rspencer@reidspencer.com>2007-02-28 22:02:48 +0000
committerReid Spencer <rspencer@reidspencer.com>2007-02-28 22:02:48 +0000
commitbb626a6751db9a63d159d32522bdf88cedf46eeb (patch)
treec1843b228be65aa4da2f0dd853cf10d29db05944 /lib/Analysis/ConstantRange.cpp
parent3da43849f2a2319ded6ed379ec8e7d620d6ac8c6 (diff)
Move ConstantRange class to lib/Support from lib/Analysis and make its
interface not depend on Type or ICmpInst. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34761 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Analysis/ConstantRange.cpp')
-rw-r--r--lib/Analysis/ConstantRange.cpp315
1 files changed, 0 insertions, 315 deletions
diff --git a/lib/Analysis/ConstantRange.cpp b/lib/Analysis/ConstantRange.cpp
deleted file mode 100644
index f419edcf9b..0000000000
--- a/lib/Analysis/ConstantRange.cpp
+++ /dev/null
@@ -1,315 +0,0 @@
-//===-- ConstantRange.cpp - ConstantRange implementation ------------------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// 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 (other integral ranges use min/max values for special range values):
-//
-// [F, F) = {} = Empty set
-// [T, F) = {T}
-// [F, T) = {F}
-// [T, T) = {F, T} = Full set
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/ConstantRange.h"
-#include "llvm/Instruction.h"
-#include "llvm/Instructions.h"
-#include "llvm/Type.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Support/Streams.h"
-#include <ostream>
-using namespace llvm;
-
-/// Initialize a full (the default) or empty set for the specified type.
-///
-ConstantRange::ConstantRange(const Type *Ty, bool Full) :
- Lower(cast<IntegerType>(Ty)->getBitWidth(), 0),
- Upper(cast<IntegerType>(Ty)->getBitWidth(), 0) {
- uint32_t BitWidth = cast<IntegerType>(Ty)->getBitWidth();
- if (Full)
- Lower = Upper = APInt::getMaxValue(BitWidth);
- else
- Lower = Upper = APInt::getMinValue(BitWidth);
-}
-
-/// Initialize a range to hold the single specified value.
-///
-ConstantRange::ConstantRange(const APInt & V) : Lower(V), Upper(V + 1) { }
-
-ConstantRange::ConstantRange(const APInt &L, const APInt &U) :
- Lower(L), Upper(U) {
- assert(L.getBitWidth() == U.getBitWidth() &&
- "ConstantRange with unequal bit widths");
- uint32_t BitWidth = L.getBitWidth();
- assert((L != U || (L == APInt::getMaxValue(BitWidth) ||
- L == APInt::getMinValue(BitWidth))) &&
- "Lower == Upper, but they aren't min or max value!");
-}
-
-/// Initialize a set of values that all satisfy the condition with C.
-///
-ConstantRange::ConstantRange(unsigned short ICmpOpcode, const APInt &C)
- : Lower(C.getBitWidth(), 0), Upper(C.getBitWidth(), 0) {
- uint32_t BitWidth = C.getBitWidth();
- switch (ICmpOpcode) {
- default: assert(0 && "Invalid ICmp opcode to ConstantRange ctor!");
- case ICmpInst::ICMP_EQ: Lower = C; Upper = C + 1; return;
- case ICmpInst::ICMP_NE: Upper = C; Lower = C + 1; return;
- case ICmpInst::ICMP_ULT:
- Lower = APInt::getMinValue(BitWidth);
- Upper = C;
- return;
- case ICmpInst::ICMP_SLT:
- Lower = APInt::getSignedMinValue(BitWidth);
- Upper = C;
- return;
- case ICmpInst::ICMP_UGT:
- Lower = C + 1;
- Upper = APInt::getMinValue(BitWidth); // Min = Next(Max)
- return;
- case ICmpInst::ICMP_SGT:
- Lower = C + 1;
- Upper = APInt::getSignedMinValue(BitWidth); // Min = Next(Max)
- return;
- case ICmpInst::ICMP_ULE:
- Lower = APInt::getMinValue(BitWidth);
- Upper = C + 1;
- return;
- case ICmpInst::ICMP_SLE:
- Lower = APInt::getSignedMinValue(BitWidth);
- Upper = C + 1;
- return;
- case ICmpInst::ICMP_UGE:
- Lower = C;
- Upper = APInt::getMinValue(BitWidth); // Min = Next(Max)
- return;
- case ICmpInst::ICMP_SGE:
- Lower = C;
- Upper = APInt::getSignedMinValue(BitWidth); // Min = Next(Max)
- return;
- }
-}
-
-/// getType - Return the LLVM data type of this range.
-///
-const Type *ConstantRange::getType() const {
- return IntegerType::get(Lower.getBitWidth());
-}
-
-/// isFullSet - Return true if this set contains all of the elements possible
-/// for this data-type
-bool ConstantRange::isFullSet() const {
- return Lower == Upper && Lower == APInt::getMaxValue(Lower.getBitWidth());
-}
-
-/// isEmptySet - Return true if this set contains no members.
-///
-bool ConstantRange::isEmptySet() const {
- return Lower == Upper && Lower == APInt::getMinValue(Lower.getBitWidth());
-}
-
-/// isWrappedSet - Return true if this set wraps around the top of the range,
-/// for example: [100, 8)
-///
-bool ConstantRange::isWrappedSet(bool isSigned) const {
- if (isSigned)
- return Lower.sgt(Upper);
- return Lower.ugt(Upper);
-}
-
-/// getSetSize - Return the number of elements in this set.
-///
-APInt ConstantRange::getSetSize() const {
- if (isEmptySet())
- return APInt(Lower.getBitWidth(), 0);
- if (getType() == Type::Int1Ty) {
- if (Lower != Upper) // One of T or F in the set...
- return APInt(Lower.getBitWidth(), 1);
- return APInt(Lower.getBitWidth(), 2); // Must be full set...
- }
-
- // Simply subtract the bounds...
- return Upper - Lower;
-}
-
-/// contains - Return true if the specified value is in the set.
-///
-bool ConstantRange::contains(const APInt &V, bool isSigned) const {
- if (Lower == Upper) {
- if (isFullSet())
- return true;
- return false;
- }
-
- if (!isWrappedSet(isSigned))
- if (isSigned)
- return Lower.sle(V) && V.slt(Upper);
- else
- return Lower.ule(V) && V.ult(Upper);
- if (isSigned)
- return Lower.sle(V) || V.slt(Upper);
- else
- return Lower.ule(V) || V.ult(Upper);
-}
-
-/// subtract - Subtract the specified constant from the endpoints of this
-/// constant range.
-ConstantRange ConstantRange::subtract(const APInt &Val) const {
- assert(Val.getBitWidth() == Lower.getBitWidth() && "Wrong bit width");
- // If the set is empty or full, don't modify the endpoints.
- if (Lower == Upper)
- return *this;
- return ConstantRange(Lower - Val, Upper - Val);
-}
-
-
-// intersect1Wrapped - This helper function is used to intersect two ranges when
-// it is known that LHS is wrapped and RHS isn't.
-//
-ConstantRange
-ConstantRange::intersect1Wrapped(const ConstantRange &LHS,
- const ConstantRange &RHS, bool isSigned) {
- assert(LHS.isWrappedSet(isSigned) && !RHS.isWrappedSet(isSigned));
-
- // Check to see if we overlap on the Left side of RHS...
- //
- bool LT = (isSigned ? RHS.Lower.slt(LHS.Upper) : RHS.Lower.ult(LHS.Upper));
- bool GT = (isSigned ? RHS.Upper.sgt(LHS.Lower) : RHS.Upper.ugt(LHS.Lower));
- if (LT) {
- // We do overlap on the left side of RHS, see if we overlap on the right of
- // RHS...
- if (GT) {
- // Ok, the result overlaps on both the left and right sides. See if the
- // resultant interval will be smaller if we wrap or not...
- //
- if (LHS.getSetSize().ult(RHS.getSetSize()))
- return LHS;
- else
- return RHS;
-
- } else {
- // No overlap on the right, just on the left.
- return ConstantRange(RHS.Lower, LHS.Upper);
- }
- } else {
- // We don't overlap on the left side of RHS, see if we overlap on the right
- // of RHS...
- if (GT) {
- // Simple overlap...
- return ConstantRange(LHS.Lower, RHS.Upper);
- } else {
- // No overlap...
- return ConstantRange(LHS.getType(), false);
- }
- }
-}
-
-/// intersectWith - Return the range that results from the intersection of this
-/// range with another range.
-///
-ConstantRange ConstantRange::intersectWith(const ConstantRange &CR,
- bool isSigned) const {
- assert(getType() == CR.getType() && "ConstantRange types don't agree!");
- // Handle common special cases
- if (isEmptySet() || CR.isFullSet())
- return *this;
- if (isFullSet() || CR.isEmptySet())
- return CR;
-
- if (!isWrappedSet(isSigned)) {
- if (!CR.isWrappedSet(isSigned)) {
- using namespace APIntOps;
- APInt L = isSigned ? smax(Lower, CR.Lower) : umax(Lower, CR.Lower);
- APInt U = isSigned ? smin(Upper, CR.Upper) : umin(Upper, CR.Upper);
-
- if (isSigned ? L.slt(U) : L.ult(U)) // If range isn't empty...
- return ConstantRange(L, U);
- else
- return ConstantRange(getType(), false); // Otherwise, return empty set
- } else
- return intersect1Wrapped(CR, *this, isSigned);
- } else { // We know "this" is wrapped...
- if (!CR.isWrappedSet(isSigned))
- return intersect1Wrapped(*this, CR, isSigned);
- else {
- // Both ranges are wrapped...
- using namespace APIntOps;
- APInt L = isSigned ? smax(Lower, CR.Lower) : umax(Lower, CR.Lower);
- APInt U = isSigned ? smin(Upper, CR.Upper) : umin(Upper, CR.Upper);
- return ConstantRange(L, U);
- }
- }
- return *this;
-}
-
-/// unionWith - 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 ConstantRange::unionWith(const ConstantRange &CR,
- bool isSigned) const {
- assert(getType() == CR.getType() && "ConstantRange types don't agree!");
-
- assert(0 && "Range union not implemented yet!");
-
- return *this;
-}
-
-/// zeroExtend - 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 as if the source range had been
-/// zero extended.
-ConstantRange ConstantRange::zeroExtend(const Type *Ty) const {
- unsigned SrcTySize = Lower.getBitWidth();
- unsigned DstTySize = Ty->getPrimitiveSizeInBits();
- assert(SrcTySize < DstTySize && "Not a value extension");
- if (isFullSet())
- // Change a source full set into [0, 1 << 8*numbytes)
- return ConstantRange(APInt(DstTySize,0), APInt(DstTySize,1).shl(SrcTySize));
-
- APInt L = Lower; L.zext(DstTySize);
- APInt U = Upper; U.zext(DstTySize);
- return ConstantRange(L, U);
-}
-
-/// truncate - 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 as if the source range had been
-/// truncated to the specified type.
-ConstantRange ConstantRange::truncate(const Type *Ty) const {
- unsigned SrcTySize = Lower.getBitWidth();
- unsigned DstTySize = Ty->getPrimitiveSizeInBits();
- assert(SrcTySize > DstTySize && "Not a value truncation");
- APInt Size = APInt::getMaxValue(DstTySize).zext(SrcTySize);
- if (isFullSet() || getSetSize().ugt(Size))
- return ConstantRange(getType());
-
- APInt L = Lower; L.trunc(DstTySize);
- APInt U = Upper; U.trunc(DstTySize);
- return ConstantRange(L, U);
-}
-
-/// print - Print out the bounds to a stream...
-///
-void ConstantRange::print(std::ostream &OS) const {
- OS << "[" << Lower.toStringSigned(10) << ","
- << Upper.toStringSigned(10) << " )";
-}
-
-/// dump - Allow printing from a debugger easily...
-///
-void ConstantRange::dump() const {
- print(cerr);
-}