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Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineAndOrXor.cpp')
-rw-r--r--lib/Transforms/InstCombine/InstCombineAndOrXor.cpp38
1 files changed, 19 insertions, 19 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 85e18a3591..7d0af0d802 100644
--- a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -315,7 +315,7 @@ Value *InstCombiner::InsertRangeTest(Value *V, Constant *Lo, Constant *Hi,
return Builder->CreateICmpUGT(Add, LowerBound);
}
-// isRunOfOnes - Returns true if Val consists of one contiguous run of 1s with
+// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s with
// any number of 0s on either side. The 1s are allowed to wrap from LSB to
// MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
// not, since all 1s are not contiguous.
@@ -335,9 +335,9 @@ static bool isRunOfOnes(ConstantInt *Val, uint32_t &MB, uint32_t &ME) {
/// where isSub determines whether the operator is a sub. If we can fold one of
/// the following xforms:
///
-/// ((A & N) +/- B) & Mask -> (A +/- B) & Mask if N&Mask == Mask
-/// ((A | N) +/- B) & Mask -> (A +/- B) & Mask if N&Mask == 0
-/// ((A ^ N) +/- B) & Mask -> (A +/- B) & Mask if N&Mask == 0
+/// ((A & N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == Mask
+/// ((A | N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
+/// ((A ^ N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
///
/// return (A +/- B).
///
@@ -752,7 +752,7 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
// (trunc x) == C1 & (and x, CA) == C2 -> (and x, CA|CMAX) == C1|C2
// where CMAX is the all ones value for the truncated type,
- // if the lower bits of C2 and CA are zero.
+ // iff the lower bits of C2 and CA are zero.
if (LHSCC == ICmpInst::ICMP_EQ && LHSCC == RHSCC &&
LHS->hasOneUse() && RHS->hasOneUse()) {
Value *V;
@@ -1062,9 +1062,9 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
break;
}
case Instruction::Add:
- // ((A & N) + B) & AndRHS -> (A + B) & AndRHS if N&AndRHS == AndRHS.
- // ((A | N) + B) & AndRHS -> (A + B) & AndRHS if N&AndRHS == 0
- // ((A ^ N) + B) & AndRHS -> (A + B) & AndRHS if N&AndRHS == 0
+ // ((A & N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == AndRHS.
+ // ((A | N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
+ // ((A ^ N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, false, I))
return BinaryOperator::CreateAnd(V, AndRHS);
if (Value *V = FoldLogicalPlusAnd(Op0RHS, Op0LHS, AndRHS, false, I))
@@ -1072,13 +1072,13 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
break;
case Instruction::Sub:
- // ((A & N) - B) & AndRHS -> (A - B) & AndRHS if N&AndRHS == AndRHS.
- // ((A | N) - B) & AndRHS -> (A - B) & AndRHS if N&AndRHS == 0
- // ((A ^ N) - B) & AndRHS -> (A - B) & AndRHS if N&AndRHS == 0
+ // ((A & N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == AndRHS.
+ // ((A | N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
+ // ((A ^ N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, true, I))
return BinaryOperator::CreateAnd(V, AndRHS);
- // (A - N) & AndRHS -> -N & AndRHS if A&AndRHS==0 and AndRHS
+ // (A - N) & AndRHS -> -N & AndRHS iff A&AndRHS==0 and AndRHS
// has 1's for all bits that the subtraction with A might affect.
if (Op0I->hasOneUse() && !match(Op0LHS, m_Zero())) {
uint32_t BitWidth = AndRHSMask.getBitWidth();
@@ -1472,7 +1472,7 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
}
// (icmp ult (X + CA), C1) | (icmp eq X, C2) -> (icmp ule (X + CA), C1)
- // if C2 + CA == C1.
+ // iff C2 + CA == C1.
if (LHSCC == ICmpInst::ICMP_ULT && RHSCC == ICmpInst::ICMP_EQ) {
ConstantInt *AddCst;
if (match(Val, m_Add(m_Specific(Val2), m_ConstantInt(AddCst))))
@@ -1735,7 +1735,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
ConstantInt *C1 = 0; Value *X = 0;
// (X & C1) | C2 --> (X | C2) & (C1|C2)
- // if (C1 & C2) == 0.
+ // iff (C1 & C2) == 0.
if (match(Op0, m_And(m_Value(X), m_ConstantInt(C1))) &&
(RHS->getValue() & C1->getValue()) != 0 &&
Op0->hasOneUse()) {
@@ -1779,7 +1779,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
return BSwap;
}
- // (X^C)|Y -> (X|Y)^C if Y&C == 0
+ // (X^C)|Y -> (X|Y)^C iff Y&C == 0
if (Op0->hasOneUse() &&
match(Op0, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
MaskedValueIsZero(Op1, C1->getValue())) {
@@ -1788,7 +1788,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
return BinaryOperator::CreateXor(NOr, C1);
}
- // Y|(X^C) -> (X|Y)^C if Y&C == 0
+ // Y|(X^C) -> (X|Y)^C iff Y&C == 0
if (Op1->hasOneUse() &&
match(Op1, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
MaskedValueIsZero(Op0, C1->getValue())) {
@@ -1830,7 +1830,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
if ((C1->getValue() & C2->getValue()) == 0) {
// ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2)
- // if (C1&C2) == 0 and (N&~C1) == 0
+ // iff (C1&C2) == 0 and (N&~C1) == 0
if (match(A, m_Or(m_Value(V1), m_Value(V2))) &&
((V1 == B && MaskedValueIsZero(V2, ~C1->getValue())) || // (V|N)
(V2 == B && MaskedValueIsZero(V1, ~C1->getValue())))) // (N|V)
@@ -1846,7 +1846,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
C1->getValue()|C2->getValue()));
// ((V|C3)&C1) | ((V|C4)&C2) --> (V|C3|C4)&(C1|C2)
- // if (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
+ // iff (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
ConstantInt *C3 = 0, *C4 = 0;
if (match(A, m_Or(m_Value(V1), m_ConstantInt(C3))) &&
(C3->getValue() & ~C1->getValue()) == 0 &&
@@ -2146,7 +2146,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
}
} else if (Op0I->getOpcode() == Instruction::Or) {
- // (X|C1)^C2 -> X^(C1|C2) if X&~C1 == 0
+ // (X|C1)^C2 -> X^(C1|C2) iff X&~C1 == 0
if (MaskedValueIsZero(Op0I->getOperand(0), Op0CI->getValue())) {
Constant *NewRHS = ConstantExpr::getOr(Op0CI, RHS);
// Anything in both C1 and C2 is known to be zero, remove it from
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-28 04:43:44 +0000