diff options
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp')
-rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp | 28 |
1 files changed, 0 insertions, 28 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index f07f64e3f02..ee51bc03312 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -69,34 +69,6 @@ static bool hasBranchUse(ICmpInst &I) { return false; } -/// Given an exploded icmp instruction, return true if the comparison only -/// checks the sign bit. If it only checks the sign bit, set TrueIfSigned if the -/// result of the comparison is true when the input value is signed. -static bool isSignBitCheck(ICmpInst::Predicate Pred, const APInt &RHS, - bool &TrueIfSigned) { - switch (Pred) { - case ICmpInst::ICMP_SLT: // True if LHS s< 0 - TrueIfSigned = true; - return RHS.isNullValue(); - case ICmpInst::ICMP_SLE: // True if LHS s<= RHS and RHS == -1 - TrueIfSigned = true; - return RHS.isAllOnesValue(); - case ICmpInst::ICMP_SGT: // True if LHS s> -1 - TrueIfSigned = false; - return RHS.isAllOnesValue(); - case ICmpInst::ICMP_UGT: - // True if LHS u> RHS and RHS == high-bit-mask - 1 - TrueIfSigned = true; - return RHS.isMaxSignedValue(); - case ICmpInst::ICMP_UGE: - // True if LHS u>= RHS and RHS == high-bit-mask (2^7, 2^15, 2^31, etc) - TrueIfSigned = true; - return RHS.isSignMask(); - default: - return false; - } -} - /// Returns true if the exploded icmp can be expressed as a signed comparison /// to zero and updates the predicate accordingly. /// The signedness of the comparison is preserved. |