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-rw-r--r--llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp28
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.
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