diff options
Diffstat (limited to 'llvm/lib/Analysis/ValueTracking.cpp')
| -rw-r--r-- | llvm/lib/Analysis/ValueTracking.cpp | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index 457e1b2..0cdfa5b 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -3397,9 +3397,6 @@ Intrinsic::ID llvm::getIntrinsicForCallSite(const CallBase &CB, /// NOTE: Do not check 'nsz' here because that fast-math-flag does not guarantee /// that a value is not -0.0. It only guarantees that -0.0 may be treated /// the same as +0.0 in floating-point ops. -/// -/// NOTE: this function will need to be revisited when we support non-default -/// rounding modes! bool llvm::CannotBeNegativeZero(const Value *V, const TargetLibraryInfo *TLI, unsigned Depth) { if (auto *CFP = dyn_cast<ConstantFP>(V)) @@ -3429,9 +3426,21 @@ bool llvm::CannotBeNegativeZero(const Value *V, const TargetLibraryInfo *TLI, case Intrinsic::sqrt: case Intrinsic::canonicalize: return CannotBeNegativeZero(Call->getArgOperand(0), TLI, Depth + 1); + case Intrinsic::experimental_constrained_sqrt: { + // NOTE: This rounding mode restriction may be too strict. + const auto *CI = cast<ConstrainedFPIntrinsic>(Call); + if (CI->getRoundingMode() == RoundingMode::NearestTiesToEven) + return CannotBeNegativeZero(Call->getArgOperand(0), TLI, Depth + 1); + else + return false; + } // fabs(x) != -0.0 case Intrinsic::fabs: return true; + // sitofp and uitofp turn into +0.0 for zero. + case Intrinsic::experimental_constrained_sitofp: + case Intrinsic::experimental_constrained_uitofp: + return true; } } |