Index: lib/Transforms/Scalar/LICM.cpp =================================================================== --- lib/Transforms/Scalar/LICM.cpp +++ lib/Transforms/Scalar/LICM.cpp @@ -438,9 +438,12 @@ return !pointerInvalidatedByLoop(LI->getOperand(0), Size, AAInfo, CurAST); } else if (CallInst *CI = dyn_cast(&I)) { - // Don't sink or hoist dbg info; it's legal, but not useful. - if (isa(I)) - return false; + // Don't sink or hoist dbg info or assumes; it's legal, but not useful. + if (auto *II = dyn_cast(&I)) { + if (isa(II) || + II->getIntrinsicID() == Intrinsic::assume) + return false; + } // Don't sink calls which can throw. if (CI->mayThrow()) Index: test/Transforms/LICM/assume.ll =================================================================== --- /dev/null +++ test/Transforms/LICM/assume.ll @@ -0,0 +1,34 @@ +; RUN: opt -licm -basicaa < %s -S | FileCheck %s + +define void @f(i1 %p) nounwind ssp { +entry: + br label %for.body + +for.body: + br i1 undef, label %if.then, label %for.cond.backedge + +for.cond.backedge: + br i1 undef, label %for.end104, label %for.body + +if.then: + br i1 undef, label %if.then27, label %if.end.if.end.split_crit_edge.critedge + +if.then27: +; CHECK: tail call void @llvm.assume + tail call void @llvm.assume(i1 %p) + br label %for.body61.us + +if.end.if.end.split_crit_edge.critedge: + br label %for.body61 + +for.body61.us: + br i1 undef, label %for.cond.backedge, label %for.body61.us + +for.body61: + br i1 undef, label %for.cond.backedge, label %for.body61 + +for.end104: + ret void +} + +declare void @llvm.assume(i1)