llvm-project/mlir/lib/Dialect/Arith/IR/InferIntRangeInterfaceImpls...

709 lines
30 KiB
C++

//===- InferIntRangeInterfaceImpls.cpp - Integer range impls for arith -===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Arith/IR/Arith.h"
#include "mlir/Interfaces/InferIntRangeInterface.h"
#include "llvm/Support/Debug.h"
#define DEBUG_TYPE "int-range-analysis"
using namespace mlir;
using namespace mlir::arith;
/// Function that evaluates the result of doing something on arithmetic
/// constants and returns std::nullopt on overflow.
using ConstArithFn =
function_ref<Optional<APInt>(const APInt &, const APInt &)>;
/// Return the maxmially wide signed or unsigned range for a given bitwidth.
/// Compute op(minLeft, minRight) and op(maxLeft, maxRight) if possible,
/// If either computation overflows, make the result unbounded.
static ConstantIntRanges computeBoundsBy(ConstArithFn op, const APInt &minLeft,
const APInt &minRight,
const APInt &maxLeft,
const APInt &maxRight, bool isSigned) {
Optional<APInt> maybeMin = op(minLeft, minRight);
Optional<APInt> maybeMax = op(maxLeft, maxRight);
if (maybeMin && maybeMax)
return ConstantIntRanges::range(*maybeMin, *maybeMax, isSigned);
return ConstantIntRanges::maxRange(minLeft.getBitWidth());
}
/// Compute the minimum and maximum of `(op(l, r) for l in lhs for r in rhs)`,
/// ignoring unbounded values. Returns the maximal range if `op` overflows.
static ConstantIntRanges minMaxBy(ConstArithFn op, ArrayRef<APInt> lhs,
ArrayRef<APInt> rhs, bool isSigned) {
unsigned width = lhs[0].getBitWidth();
APInt min =
isSigned ? APInt::getSignedMaxValue(width) : APInt::getMaxValue(width);
APInt max =
isSigned ? APInt::getSignedMinValue(width) : APInt::getZero(width);
for (const APInt &left : lhs) {
for (const APInt &right : rhs) {
Optional<APInt> maybeThisResult = op(left, right);
if (!maybeThisResult)
return ConstantIntRanges::maxRange(width);
APInt result = std::move(*maybeThisResult);
min = (isSigned ? result.slt(min) : result.ult(min)) ? result : min;
max = (isSigned ? result.sgt(max) : result.ugt(max)) ? result : max;
}
}
return ConstantIntRanges::range(min, max, isSigned);
}
//===----------------------------------------------------------------------===//
// ConstantOp
//===----------------------------------------------------------------------===//
void arith::ConstantOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
auto constAttr = getValue().dyn_cast_or_null<IntegerAttr>();
if (constAttr) {
const APInt &value = constAttr.getValue();
setResultRange(getResult(), ConstantIntRanges::constant(value));
}
}
//===----------------------------------------------------------------------===//
// AddIOp
//===----------------------------------------------------------------------===//
void arith::AddIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
ConstArithFn uadd = [](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.uadd_ov(b, overflowed);
return overflowed ? Optional<APInt>() : result;
};
ConstArithFn sadd = [](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.sadd_ov(b, overflowed);
return overflowed ? Optional<APInt>() : result;
};
ConstantIntRanges urange = computeBoundsBy(
uadd, lhs.umin(), rhs.umin(), lhs.umax(), rhs.umax(), /*isSigned=*/false);
ConstantIntRanges srange = computeBoundsBy(
sadd, lhs.smin(), rhs.smin(), lhs.smax(), rhs.smax(), /*isSigned=*/true);
setResultRange(getResult(), urange.intersection(srange));
}
//===----------------------------------------------------------------------===//
// SubIOp
//===----------------------------------------------------------------------===//
void arith::SubIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
ConstArithFn usub = [](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.usub_ov(b, overflowed);
return overflowed ? Optional<APInt>() : result;
};
ConstArithFn ssub = [](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.ssub_ov(b, overflowed);
return overflowed ? Optional<APInt>() : result;
};
ConstantIntRanges urange = computeBoundsBy(
usub, lhs.umin(), rhs.umax(), lhs.umax(), rhs.umin(), /*isSigned=*/false);
ConstantIntRanges srange = computeBoundsBy(
ssub, lhs.smin(), rhs.smax(), lhs.smax(), rhs.smin(), /*isSigned=*/true);
setResultRange(getResult(), urange.intersection(srange));
}
//===----------------------------------------------------------------------===//
// MulIOp
//===----------------------------------------------------------------------===//
void arith::MulIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
ConstArithFn umul = [](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.umul_ov(b, overflowed);
return overflowed ? Optional<APInt>() : result;
};
ConstArithFn smul = [](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.smul_ov(b, overflowed);
return overflowed ? Optional<APInt>() : result;
};
ConstantIntRanges urange =
minMaxBy(umul, {lhs.umin(), lhs.umax()}, {rhs.umin(), rhs.umax()},
/*isSigned=*/false);
ConstantIntRanges srange =
minMaxBy(smul, {lhs.smin(), lhs.smax()}, {rhs.smin(), rhs.smax()},
/*isSigned=*/true);
setResultRange(getResult(), urange.intersection(srange));
}
//===----------------------------------------------------------------------===//
// DivUIOp
//===----------------------------------------------------------------------===//
/// Fix up division results (ex. for ceiling and floor), returning an APInt
/// if there has been no overflow
using DivisionFixupFn = function_ref<Optional<APInt>(
const APInt &lhs, const APInt &rhs, const APInt &result)>;
static ConstantIntRanges inferDivUIRange(const ConstantIntRanges &lhs,
const ConstantIntRanges &rhs,
DivisionFixupFn fixup) {
const APInt &lhsMin = lhs.umin(), &lhsMax = lhs.umax(), &rhsMin = rhs.umin(),
&rhsMax = rhs.umax();
if (!rhsMin.isZero()) {
auto udiv = [&fixup](const APInt &a, const APInt &b) -> Optional<APInt> {
return fixup(a, b, a.udiv(b));
};
return minMaxBy(udiv, {lhsMin, lhsMax}, {rhsMin, rhsMax},
/*isSigned=*/false);
}
// Otherwise, it's possible we might divide by 0.
return ConstantIntRanges::maxRange(rhsMin.getBitWidth());
}
void arith::DivUIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
setResultRange(getResult(),
inferDivUIRange(argRanges[0], argRanges[1],
[](const APInt &lhs, const APInt &rhs,
const APInt &result) { return result; }));
}
//===----------------------------------------------------------------------===//
// DivSIOp
//===----------------------------------------------------------------------===//
static ConstantIntRanges inferDivSIRange(const ConstantIntRanges &lhs,
const ConstantIntRanges &rhs,
DivisionFixupFn fixup) {
const APInt &lhsMin = lhs.smin(), &lhsMax = lhs.smax(), &rhsMin = rhs.smin(),
&rhsMax = rhs.smax();
bool canDivide = rhsMin.isStrictlyPositive() || rhsMax.isNegative();
if (canDivide) {
auto sdiv = [&fixup](const APInt &a, const APInt &b) -> Optional<APInt> {
bool overflowed = false;
APInt result = a.sdiv_ov(b, overflowed);
return overflowed ? Optional<APInt>() : fixup(a, b, result);
};
return minMaxBy(sdiv, {lhsMin, lhsMax}, {rhsMin, rhsMax},
/*isSigned=*/true);
}
return ConstantIntRanges::maxRange(rhsMin.getBitWidth());
}
void arith::DivSIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
setResultRange(getResult(),
inferDivSIRange(argRanges[0], argRanges[1],
[](const APInt &lhs, const APInt &rhs,
const APInt &result) { return result; }));
}
//===----------------------------------------------------------------------===//
// CeilDivUIOp
//===----------------------------------------------------------------------===//
void arith::CeilDivUIOp::inferResultRanges(
ArrayRef<ConstantIntRanges> argRanges, SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
DivisionFixupFn ceilDivUIFix = [](const APInt &lhs, const APInt &rhs,
const APInt &result) -> Optional<APInt> {
if (!lhs.urem(rhs).isZero()) {
bool overflowed = false;
APInt corrected =
result.uadd_ov(APInt(result.getBitWidth(), 1), overflowed);
return overflowed ? Optional<APInt>() : corrected;
}
return result;
};
setResultRange(getResult(), inferDivUIRange(lhs, rhs, ceilDivUIFix));
}
//===----------------------------------------------------------------------===//
// CeilDivSIOp
//===----------------------------------------------------------------------===//
void arith::CeilDivSIOp::inferResultRanges(
ArrayRef<ConstantIntRanges> argRanges, SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
DivisionFixupFn ceilDivSIFix = [](const APInt &lhs, const APInt &rhs,
const APInt &result) -> Optional<APInt> {
if (!lhs.srem(rhs).isZero() && lhs.isNonNegative() == rhs.isNonNegative()) {
bool overflowed = false;
APInt corrected =
result.sadd_ov(APInt(result.getBitWidth(), 1), overflowed);
return overflowed ? Optional<APInt>() : corrected;
}
return result;
};
setResultRange(getResult(), inferDivSIRange(lhs, rhs, ceilDivSIFix));
}
//===----------------------------------------------------------------------===//
// FloorDivSIOp
//===----------------------------------------------------------------------===//
void arith::FloorDivSIOp::inferResultRanges(
ArrayRef<ConstantIntRanges> argRanges, SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
DivisionFixupFn floorDivSIFix = [](const APInt &lhs, const APInt &rhs,
const APInt &result) -> Optional<APInt> {
if (!lhs.srem(rhs).isZero() && lhs.isNonNegative() != rhs.isNonNegative()) {
bool overflowed = false;
APInt corrected =
result.ssub_ov(APInt(result.getBitWidth(), 1), overflowed);
return overflowed ? Optional<APInt>() : corrected;
}
return result;
};
setResultRange(getResult(), inferDivSIRange(lhs, rhs, floorDivSIFix));
}
//===----------------------------------------------------------------------===//
// RemUIOp
//===----------------------------------------------------------------------===//
void arith::RemUIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
const APInt &rhsMin = rhs.umin(), &rhsMax = rhs.umax();
unsigned width = rhsMin.getBitWidth();
APInt umin = APInt::getZero(width);
APInt umax = APInt::getMaxValue(width);
if (!rhsMin.isZero()) {
umax = rhsMax - 1;
// Special case: sweeping out a contiguous range in N/[modulus]
if (rhsMin == rhsMax) {
const APInt &lhsMin = lhs.umin(), &lhsMax = lhs.umax();
if ((lhsMax - lhsMin).ult(rhsMax)) {
APInt minRem = lhsMin.urem(rhsMax);
APInt maxRem = lhsMax.urem(rhsMax);
if (minRem.ule(maxRem)) {
umin = minRem;
umax = maxRem;
}
}
}
}
setResultRange(getResult(), ConstantIntRanges::fromUnsigned(umin, umax));
}
//===----------------------------------------------------------------------===//
// RemSIOp
//===----------------------------------------------------------------------===//
void arith::RemSIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
const APInt &lhsMin = lhs.smin(), &lhsMax = lhs.smax(), &rhsMin = rhs.smin(),
&rhsMax = rhs.smax();
unsigned width = rhsMax.getBitWidth();
APInt smin = APInt::getSignedMinValue(width);
APInt smax = APInt::getSignedMaxValue(width);
// No bounds if zero could be a divisor.
bool canBound = (rhsMin.isStrictlyPositive() || rhsMax.isNegative());
if (canBound) {
APInt maxDivisor = rhsMin.isStrictlyPositive() ? rhsMax : rhsMin.abs();
bool canNegativeDividend = lhsMin.isNegative();
bool canPositiveDividend = lhsMax.isStrictlyPositive();
APInt zero = APInt::getZero(maxDivisor.getBitWidth());
APInt maxPositiveResult = maxDivisor - 1;
APInt minNegativeResult = -maxPositiveResult;
smin = canNegativeDividend ? minNegativeResult : zero;
smax = canPositiveDividend ? maxPositiveResult : zero;
// Special case: sweeping out a contiguous range in N/[modulus].
if (rhsMin == rhsMax) {
if ((lhsMax - lhsMin).ult(maxDivisor)) {
APInt minRem = lhsMin.srem(maxDivisor);
APInt maxRem = lhsMax.srem(maxDivisor);
if (minRem.sle(maxRem)) {
smin = minRem;
smax = maxRem;
}
}
}
}
setResultRange(getResult(), ConstantIntRanges::fromSigned(smin, smax));
}
//===----------------------------------------------------------------------===//
// AndIOp
//===----------------------------------------------------------------------===//
/// "Widen" bounds - if 0bvvvvv??? <= a <= 0bvvvvv???,
/// relax the bounds to 0bvvvvv000 <= a <= 0bvvvvv111, where vvvvv are the bits
/// that both bonuds have in common. This gives us a consertive approximation
/// for what values can be passed to bitwise operations.
static std::tuple<APInt, APInt>
widenBitwiseBounds(const ConstantIntRanges &bound) {
APInt leftVal = bound.umin(), rightVal = bound.umax();
unsigned bitwidth = leftVal.getBitWidth();
unsigned differingBits = bitwidth - (leftVal ^ rightVal).countLeadingZeros();
leftVal.clearLowBits(differingBits);
rightVal.setLowBits(differingBits);
return std::make_tuple(std::move(leftVal), std::move(rightVal));
}
void arith::AndIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
auto [lhsZeros, lhsOnes] = widenBitwiseBounds(argRanges[0]);
auto [rhsZeros, rhsOnes] = widenBitwiseBounds(argRanges[1]);
auto andi = [](const APInt &a, const APInt &b) -> Optional<APInt> {
return a & b;
};
setResultRange(getResult(),
minMaxBy(andi, {lhsZeros, lhsOnes}, {rhsZeros, rhsOnes},
/*isSigned=*/false));
}
//===----------------------------------------------------------------------===//
// OrIOp
//===----------------------------------------------------------------------===//
void arith::OrIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
auto [lhsZeros, lhsOnes] = widenBitwiseBounds(argRanges[0]);
auto [rhsZeros, rhsOnes] = widenBitwiseBounds(argRanges[1]);
auto ori = [](const APInt &a, const APInt &b) -> Optional<APInt> {
return a | b;
};
setResultRange(getResult(),
minMaxBy(ori, {lhsZeros, lhsOnes}, {rhsZeros, rhsOnes},
/*isSigned=*/false));
}
//===----------------------------------------------------------------------===//
// XOrIOp
//===----------------------------------------------------------------------===//
void arith::XOrIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
auto [lhsZeros, lhsOnes] = widenBitwiseBounds(argRanges[0]);
auto [rhsZeros, rhsOnes] = widenBitwiseBounds(argRanges[1]);
auto xori = [](const APInt &a, const APInt &b) -> Optional<APInt> {
return a ^ b;
};
setResultRange(getResult(),
minMaxBy(xori, {lhsZeros, lhsOnes}, {rhsZeros, rhsOnes},
/*isSigned=*/false));
}
//===----------------------------------------------------------------------===//
// MaxSIOp
//===----------------------------------------------------------------------===//
void arith::MaxSIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
const APInt &smin = lhs.smin().sgt(rhs.smin()) ? lhs.smin() : rhs.smin();
const APInt &smax = lhs.smax().sgt(rhs.smax()) ? lhs.smax() : rhs.smax();
setResultRange(getResult(), ConstantIntRanges::fromSigned(smin, smax));
}
//===----------------------------------------------------------------------===//
// MaxUIOp
//===----------------------------------------------------------------------===//
void arith::MaxUIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
const APInt &umin = lhs.umin().ugt(rhs.umin()) ? lhs.umin() : rhs.umin();
const APInt &umax = lhs.umax().ugt(rhs.umax()) ? lhs.umax() : rhs.umax();
setResultRange(getResult(), ConstantIntRanges::fromUnsigned(umin, umax));
}
//===----------------------------------------------------------------------===//
// MinSIOp
//===----------------------------------------------------------------------===//
void arith::MinSIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
const APInt &smin = lhs.smin().slt(rhs.smin()) ? lhs.smin() : rhs.smin();
const APInt &smax = lhs.smax().slt(rhs.smax()) ? lhs.smax() : rhs.smax();
setResultRange(getResult(), ConstantIntRanges::fromSigned(smin, smax));
}
//===----------------------------------------------------------------------===//
// MinUIOp
//===----------------------------------------------------------------------===//
void arith::MinUIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
const APInt &umin = lhs.umin().ult(rhs.umin()) ? lhs.umin() : rhs.umin();
const APInt &umax = lhs.umax().ult(rhs.umax()) ? lhs.umax() : rhs.umax();
setResultRange(getResult(), ConstantIntRanges::fromUnsigned(umin, umax));
}
//===----------------------------------------------------------------------===//
// ExtUIOp
//===----------------------------------------------------------------------===//
static ConstantIntRanges extUIRange(const ConstantIntRanges &range,
Type destType) {
unsigned destWidth = ConstantIntRanges::getStorageBitwidth(destType);
APInt smin = range.umin().zext(destWidth);
APInt smax = range.umax().zext(destWidth);
return ConstantIntRanges::fromSigned(smin, smax);
}
void arith::ExtUIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
Type destType = getResult().getType();
setResultRange(getResult(), extUIRange(argRanges[0], destType));
}
//===----------------------------------------------------------------------===//
// ExtSIOp
//===----------------------------------------------------------------------===//
static ConstantIntRanges extSIRange(const ConstantIntRanges &range,
Type destType) {
unsigned destWidth = ConstantIntRanges::getStorageBitwidth(destType);
APInt smin = range.smin().sext(destWidth);
APInt smax = range.smax().sext(destWidth);
return ConstantIntRanges::fromSigned(smin, smax);
}
void arith::ExtSIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
Type destType = getResult().getType();
setResultRange(getResult(), extSIRange(argRanges[0], destType));
}
//===----------------------------------------------------------------------===//
// TruncIOp
//===----------------------------------------------------------------------===//
static ConstantIntRanges truncIRange(const ConstantIntRanges &range,
Type destType) {
unsigned destWidth = ConstantIntRanges::getStorageBitwidth(destType);
// If you truncate the first four bytes in [0xaaaabbbb, 0xccccbbbb],
// the range of the resulting value is not contiguous ind includes 0.
// Ex. If you truncate [256, 258] from i16 to i8, you validly get [0, 2],
// but you can't truncate [255, 257] similarly.
bool hasUnsignedRollover =
range.umin().lshr(destWidth) != range.umax().lshr(destWidth);
APInt umin = hasUnsignedRollover ? APInt::getZero(destWidth)
: range.umin().trunc(destWidth);
APInt umax = hasUnsignedRollover ? APInt::getMaxValue(destWidth)
: range.umax().trunc(destWidth);
// Signed post-truncation rollover will not occur when either:
// - The high parts of the min and max, plus the sign bit, are the same
// - The high halves + sign bit of the min and max are either all 1s or all 0s
// and you won't create a [positive, negative] range by truncating.
// For example, you can truncate the ranges [256, 258]_i16 to [0, 2]_i8
// but not [255, 257]_i16 to a range of i8s. You can also truncate
// [-256, -256]_i16 to [-2, 0]_i8, but not [-257, -255]_i16.
// You can also truncate [-130, 0]_i16 to i8 because -130_i16 (0xff7e)
// will truncate to 0x7e, which is greater than 0
APInt sminHighPart = range.smin().ashr(destWidth - 1);
APInt smaxHighPart = range.smax().ashr(destWidth - 1);
bool hasSignedOverflow =
(sminHighPart != smaxHighPart) &&
!(sminHighPart.isAllOnes() &&
(smaxHighPart.isAllOnes() || smaxHighPart.isZero())) &&
!(sminHighPart.isZero() && smaxHighPart.isZero());
APInt smin = hasSignedOverflow ? APInt::getSignedMinValue(destWidth)
: range.smin().trunc(destWidth);
APInt smax = hasSignedOverflow ? APInt::getSignedMaxValue(destWidth)
: range.smax().trunc(destWidth);
return {umin, umax, smin, smax};
}
void arith::TruncIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
Type destType = getResult().getType();
setResultRange(getResult(), truncIRange(argRanges[0], destType));
}
//===----------------------------------------------------------------------===//
// IndexCastOp
//===----------------------------------------------------------------------===//
void arith::IndexCastOp::inferResultRanges(
ArrayRef<ConstantIntRanges> argRanges, SetIntRangeFn setResultRange) {
Type sourceType = getOperand().getType();
Type destType = getResult().getType();
unsigned srcWidth = ConstantIntRanges::getStorageBitwidth(sourceType);
unsigned destWidth = ConstantIntRanges::getStorageBitwidth(destType);
if (srcWidth < destWidth)
setResultRange(getResult(), extSIRange(argRanges[0], destType));
else if (srcWidth > destWidth)
setResultRange(getResult(), truncIRange(argRanges[0], destType));
else
setResultRange(getResult(), argRanges[0]);
}
//===----------------------------------------------------------------------===//
// IndexCastUIOp
//===----------------------------------------------------------------------===//
void arith::IndexCastUIOp::inferResultRanges(
ArrayRef<ConstantIntRanges> argRanges, SetIntRangeFn setResultRange) {
Type sourceType = getOperand().getType();
Type destType = getResult().getType();
unsigned srcWidth = ConstantIntRanges::getStorageBitwidth(sourceType);
unsigned destWidth = ConstantIntRanges::getStorageBitwidth(destType);
if (srcWidth < destWidth)
setResultRange(getResult(), extUIRange(argRanges[0], destType));
else if (srcWidth > destWidth)
setResultRange(getResult(), truncIRange(argRanges[0], destType));
else
setResultRange(getResult(), argRanges[0]);
}
//===----------------------------------------------------------------------===//
// CmpIOp
//===----------------------------------------------------------------------===//
bool isStaticallyTrue(arith::CmpIPredicate pred, const ConstantIntRanges &lhs,
const ConstantIntRanges &rhs) {
switch (pred) {
case arith::CmpIPredicate::sle:
case arith::CmpIPredicate::slt:
return (applyCmpPredicate(pred, lhs.smax(), rhs.smin()));
case arith::CmpIPredicate::ule:
case arith::CmpIPredicate::ult:
return applyCmpPredicate(pred, lhs.umax(), rhs.umin());
case arith::CmpIPredicate::sge:
case arith::CmpIPredicate::sgt:
return applyCmpPredicate(pred, lhs.smin(), rhs.smax());
case arith::CmpIPredicate::uge:
case arith::CmpIPredicate::ugt:
return applyCmpPredicate(pred, lhs.umin(), rhs.umax());
case arith::CmpIPredicate::eq: {
Optional<APInt> lhsConst = lhs.getConstantValue();
Optional<APInt> rhsConst = rhs.getConstantValue();
return lhsConst && rhsConst && lhsConst == rhsConst;
}
case arith::CmpIPredicate::ne: {
// While equality requires that there is an interpration of the preceeding
// computations that produces equal constants, whether that be signed or
// unsigned, statically determining inequality requires that neither
// interpretation produce potentially overlapping ranges.
bool sne = isStaticallyTrue(CmpIPredicate::slt, lhs, rhs) ||
isStaticallyTrue(CmpIPredicate::sgt, lhs, rhs);
bool une = isStaticallyTrue(CmpIPredicate::ult, lhs, rhs) ||
isStaticallyTrue(CmpIPredicate::ugt, lhs, rhs);
return sne && une;
}
}
return false;
}
void arith::CmpIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
arith::CmpIPredicate pred = getPredicate();
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
APInt min = APInt::getZero(1);
APInt max = APInt::getAllOnesValue(1);
if (isStaticallyTrue(pred, lhs, rhs))
min = max;
else if (isStaticallyTrue(invertPredicate(pred), lhs, rhs))
max = min;
setResultRange(getResult(), ConstantIntRanges::fromUnsigned(min, max));
}
//===----------------------------------------------------------------------===//
// SelectOp
//===----------------------------------------------------------------------===//
void arith::SelectOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
Optional<APInt> mbCondVal = argRanges[0].getConstantValue();
if (mbCondVal) {
if (mbCondVal->isZero())
setResultRange(getResult(), argRanges[2]);
else
setResultRange(getResult(), argRanges[1]);
return;
}
setResultRange(getResult(), argRanges[1].rangeUnion(argRanges[2]));
}
//===----------------------------------------------------------------------===//
// ShLIOp
//===----------------------------------------------------------------------===//
void arith::ShLIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
ConstArithFn shl = [](const APInt &l, const APInt &r) -> Optional<APInt> {
return r.uge(r.getBitWidth()) ? Optional<APInt>() : l.shl(r);
};
ConstantIntRanges urange =
minMaxBy(shl, {lhs.umin(), lhs.umax()}, {rhs.umin(), rhs.umax()},
/*isSigned=*/false);
ConstantIntRanges srange =
minMaxBy(shl, {lhs.smin(), lhs.smax()}, {rhs.umin(), rhs.umax()},
/*isSigned=*/true);
setResultRange(getResult(), urange.intersection(srange));
}
//===----------------------------------------------------------------------===//
// ShRUIOp
//===----------------------------------------------------------------------===//
void arith::ShRUIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
ConstArithFn lshr = [](const APInt &l, const APInt &r) -> Optional<APInt> {
return r.uge(r.getBitWidth()) ? Optional<APInt>() : l.lshr(r);
};
setResultRange(getResult(), minMaxBy(lshr, {lhs.umin(), lhs.umax()},
{rhs.umin(), rhs.umax()},
/*isSigned=*/false));
}
//===----------------------------------------------------------------------===//
// ShRSIOp
//===----------------------------------------------------------------------===//
void arith::ShRSIOp::inferResultRanges(ArrayRef<ConstantIntRanges> argRanges,
SetIntRangeFn setResultRange) {
const ConstantIntRanges &lhs = argRanges[0], &rhs = argRanges[1];
ConstArithFn ashr = [](const APInt &l, const APInt &r) -> Optional<APInt> {
return r.uge(r.getBitWidth()) ? Optional<APInt>() : l.ashr(r);
};
setResultRange(getResult(),
minMaxBy(ashr, {lhs.smin(), lhs.smax()},
{rhs.umin(), rhs.umax()}, /*isSigned=*/true));
}