return m_CombineOr(m_And(L, R), m_And(R, L));
}
+template<typename LHS, typename RHS>
+inline match_combine_or<BinaryOp_match<LHS, RHS, Instruction::Or>,
+ BinaryOp_match<RHS, LHS, Instruction::Or>>
+m_c_Or(const LHS &L, const RHS &R) {
+ return m_CombineOr(m_Or(L, R), m_Or(R, L));
+}
+
+template<typename LHS, typename RHS>
+inline match_combine_or<BinaryOp_match<LHS, RHS, Instruction::Xor>,
+ BinaryOp_match<RHS, LHS, Instruction::Xor>>
+m_c_Xor(const LHS &L, const RHS &R) {
+ return m_CombineOr(m_Xor(L, R), m_Xor(R, L));
+}
+
static void computeKnownBitsFromAssume(Value *V, APInt &KnownZero,
APInt &KnownOne,
const DataLayout *DL,
m_BitCast(m_Specific(V))));
CmpInst::Predicate Pred;
+ ConstantInt *C;
// assume(v = a)
if (match(I, m_Intrinsic<Intrinsic::assume>(
m_c_ICmp(Pred, m_V, m_Value(A)))) &&
// known bits from the RHS to V.
KnownZero |= RHSKnownZero & MaskKnownOne;
KnownOne |= RHSKnownOne & MaskKnownOne;
+ // assume(~(v & b) = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_Not(m_c_And(m_V, m_Value(B))),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ APInt MaskKnownZero(BitWidth, 0), MaskKnownOne(BitWidth, 0);
+ computeKnownBits(B, MaskKnownZero, MaskKnownOne, DL, Depth+1, Query(Q, I));
+
+ // For those bits in the mask that are known to be one, we can propagate
+ // inverted known bits from the RHS to V.
+ KnownZero |= RHSKnownOne & MaskKnownOne;
+ KnownOne |= RHSKnownZero & MaskKnownOne;
+ // assume(v | b = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_c_Or(m_V, m_Value(B)), m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ APInt BKnownZero(BitWidth, 0), BKnownOne(BitWidth, 0);
+ computeKnownBits(B, BKnownZero, BKnownOne, DL, Depth+1, Query(Q, I));
+
+ // For those bits in B that are known to be zero, we can propagate known
+ // bits from the RHS to V.
+ KnownZero |= RHSKnownZero & BKnownZero;
+ KnownOne |= RHSKnownOne & BKnownZero;
+ // assume(~(v | b) = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_Not(m_c_Or(m_V, m_Value(B))),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ APInt BKnownZero(BitWidth, 0), BKnownOne(BitWidth, 0);
+ computeKnownBits(B, BKnownZero, BKnownOne, DL, Depth+1, Query(Q, I));
+
+ // For those bits in B that are known to be zero, we can propagate
+ // inverted known bits from the RHS to V.
+ KnownZero |= RHSKnownOne & BKnownZero;
+ KnownOne |= RHSKnownZero & BKnownZero;
+ // assume(v ^ b = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_c_Xor(m_V, m_Value(B)), m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ APInt BKnownZero(BitWidth, 0), BKnownOne(BitWidth, 0);
+ computeKnownBits(B, BKnownZero, BKnownOne, DL, Depth+1, Query(Q, I));
+
+ // For those bits in B that are known to be zero, we can propagate known
+ // bits from the RHS to V. For those bits in B that are known to be one,
+ // we can propagate inverted known bits from the RHS to V.
+ KnownZero |= RHSKnownZero & BKnownZero;
+ KnownOne |= RHSKnownOne & BKnownZero;
+ KnownZero |= RHSKnownOne & BKnownOne;
+ KnownOne |= RHSKnownZero & BKnownOne;
+ // assume(~(v ^ b) = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_Not(m_c_Xor(m_V, m_Value(B))),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ APInt BKnownZero(BitWidth, 0), BKnownOne(BitWidth, 0);
+ computeKnownBits(B, BKnownZero, BKnownOne, DL, Depth+1, Query(Q, I));
+
+ // For those bits in B that are known to be zero, we can propagate
+ // inverted known bits from the RHS to V. For those bits in B that are
+ // known to be one, we can propagate known bits from the RHS to V.
+ KnownZero |= RHSKnownOne & BKnownZero;
+ KnownOne |= RHSKnownZero & BKnownZero;
+ KnownZero |= RHSKnownZero & BKnownOne;
+ KnownOne |= RHSKnownOne & BKnownOne;
+ // assume(v << c = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_Shl(m_V, m_ConstantInt(C)),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ // For those bits in RHS that are known, we can propagate them to known
+ // bits in V shifted to the right by C.
+ KnownZero |= RHSKnownZero.lshr(C->getZExtValue());
+ KnownOne |= RHSKnownOne.lshr(C->getZExtValue());
+ // assume(~(v << c) = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_Not(m_Shl(m_V, m_ConstantInt(C))),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ // For those bits in RHS that are known, we can propagate them inverted
+ // to known bits in V shifted to the right by C.
+ KnownZero |= RHSKnownOne.lshr(C->getZExtValue());
+ KnownOne |= RHSKnownZero.lshr(C->getZExtValue());
+ // assume(v >> c = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_CombineOr(m_LShr(m_V, m_ConstantInt(C)),
+ m_AShr(m_V,
+ m_ConstantInt(C))),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ // For those bits in RHS that are known, we can propagate them to known
+ // bits in V shifted to the right by C.
+ KnownZero |= RHSKnownZero << C->getZExtValue();
+ KnownOne |= RHSKnownOne << C->getZExtValue();
+ // assume(~(v >> c) = a)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_c_ICmp(Pred, m_Not(m_CombineOr(
+ m_LShr(m_V, m_ConstantInt(C)),
+ m_AShr(m_V, m_ConstantInt(C)))),
+ m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_EQ && isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+ // For those bits in RHS that are known, we can propagate them inverted
+ // to known bits in V shifted to the right by C.
+ KnownZero |= RHSKnownOne << C->getZExtValue();
+ KnownOne |= RHSKnownZero << C->getZExtValue();
+ // assume(v >=_s c) where c is non-negative
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_ICmp(Pred, m_V, m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_SGE &&
+ isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+
+ if (RHSKnownZero.isNegative()) {
+ // We know that the sign bit is zero.
+ KnownZero |= APInt::getSignBit(BitWidth);
+ }
+ // assume(v >_s c) where c is at least -1.
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_ICmp(Pred, m_V, m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_SGT &&
+ isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+
+ if (RHSKnownOne.isAllOnesValue() || RHSKnownZero.isNegative()) {
+ // We know that the sign bit is zero.
+ KnownZero |= APInt::getSignBit(BitWidth);
+ }
+ // assume(v <=_s c) where c is negative
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_ICmp(Pred, m_V, m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_SLE &&
+ isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+
+ if (RHSKnownOne.isNegative()) {
+ // We know that the sign bit is one.
+ KnownOne |= APInt::getSignBit(BitWidth);
+ }
+ // assume(v <_s c) where c is non-positive
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_ICmp(Pred, m_V, m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_SLT &&
+ isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+
+ if (RHSKnownZero.isAllOnesValue() || RHSKnownOne.isNegative()) {
+ // We know that the sign bit is one.
+ KnownOne |= APInt::getSignBit(BitWidth);
+ }
+ // assume(v <=_u c)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_ICmp(Pred, m_V, m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_ULE &&
+ isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+
+ // Whatever high bits in c are zero are known to be zero.
+ KnownZero |=
+ APInt::getHighBitsSet(BitWidth, RHSKnownZero.countLeadingOnes());
+ // assume(v <_u c)
+ } else if (match(I, m_Intrinsic<Intrinsic::assume>(
+ m_ICmp(Pred, m_V, m_Value(A)))) &&
+ Pred == ICmpInst::ICMP_ULT &&
+ isValidAssumeForContext(I, Q, DL)) {
+ APInt RHSKnownZero(BitWidth, 0), RHSKnownOne(BitWidth, 0);
+ computeKnownBits(A, RHSKnownZero, RHSKnownOne, DL, Depth+1, Query(Q, I));
+
+ // Whatever high bits in c are zero are known to be zero (if c is a power
+ // of 2, then one more).
+ if (isKnownToBeAPowerOfTwo(A, false, Depth+1, Query(Q, I)))
+ KnownZero |=
+ APInt::getHighBitsSet(BitWidth, RHSKnownZero.countLeadingOnes()+1);
+ else
+ KnownZero |=
+ APInt::getHighBitsSet(BitWidth, RHSKnownZero.countLeadingOnes());
}
}
}
projects / oota-llvm.git / blobdiff