Summary:
programUndefinedIfPoison makes more sense, given what the function
does; and I'm about to add a function with a name similar to
isKnownNotFullPoison (so do the rename to avoid confusion).
Reviewers: broune, majnemer, bjarke.roune
Reviewed By: broune
Subscribers: mcrosier, llvm-commits, mzolotukhin
Differential Revision: https://reviews.llvm.org/D30444
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301776
91177308-0d34-0410-b5e6-
96231b3b80d8
///
/// Note that this currently only considers the basic block that is
/// the parent of I.
- bool isKnownNotFullPoison(const Instruction *PoisonI);
+ bool programUndefinedIfFullPoison(const Instruction *PoisonI);
/// \brief Specific patterns of select instructions we can match.
enum SelectPatternFlavor {
return false;
// Only proceed if we can prove that I does not yield poison.
- if (!isKnownNotFullPoison(I)) return false;
+ if (!programUndefinedIfFullPoison(I))
+ return false;
// At this point we know that if I is executed, then it does not wrap
// according to at least one of NSW or NUW. If I is not executed, then we do
}
}
-bool llvm::isKnownNotFullPoison(const Instruction *PoisonI) {
+bool llvm::programUndefinedIfFullPoison(const Instruction *PoisonI) {
// We currently only look for uses of poison values within the same basic
// block, as that makes it easier to guarantee that the uses will be
// executed given that PoisonI is executed.
// Add I to DominatingExprs if it's an add/sub that can't sign overflow.
if (match(I, m_NSWAdd(m_Value(LHS), m_Value(RHS))) ||
match(I, m_NSWSub(m_Value(LHS), m_Value(RHS)))) {
- if (isKnownNotFullPoison(I)) {
+ if (programUndefinedIfFullPoison(I)) {
const SCEV *Key =
SE->getAddExpr(SE->getUnknown(LHS), SE->getUnknown(RHS));
DominatingExprs[Key].push_back(I);
ret void
}
-; Demonstrate why we need a Visited set in llvm::isKnownNotFullPoison.
+; Demonstrate why we need a Visited set in llvm::programUndefinedIfFullPoison.
define void @test-add-not-header5(float* %input, i32 %offset) {
; CHECK-LABEL: @test-add-not-header5
entry: