From 7ccebec66883b6e97a22a4e711b7c4585e94a186 Mon Sep 17 00:00:00 2001 From: Juergen Ributzka Date: Mon, 27 Oct 2014 19:58:36 +0000 Subject: [FastISel][AArch64] Emit immediate version of icmp (subs) for null pointer check. This is a minor change to use the immediate version when the operand is a null value. This should get rid of an unnecessary 'mov' instruction in debug builds and align the code more with the one generated by SelectionDAG. This fixes rdar://problem/18785125. llvm-svn: 220713 --- llvm/lib/Target/AArch64/AArch64FastISel.cpp | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'llvm/lib') diff --git a/llvm/lib/Target/AArch64/AArch64FastISel.cpp b/llvm/lib/Target/AArch64/AArch64FastISel.cpp index 5527213c89d..01b2dee2612 100644 --- a/llvm/lib/Target/AArch64/AArch64FastISel.cpp +++ b/llvm/lib/Target/AArch64/AArch64FastISel.cpp @@ -1084,7 +1084,7 @@ unsigned AArch64FastISel::emitAddSub(bool UseAdd, MVT RetVT, const Value *LHS, RetVT.SimpleTy = std::max(RetVT.SimpleTy, MVT::i32); // Canonicalize immediates to the RHS first. - if (UseAdd && isa(LHS) && !isa(RHS)) + if (UseAdd && isa(LHS) && !isa(RHS)) std::swap(LHS, RHS); // Canonicalize mul by power of 2 to the RHS. @@ -1118,7 +1118,11 @@ unsigned AArch64FastISel::emitAddSub(bool UseAdd, MVT RetVT, const Value *LHS, else ResultReg = emitAddSub_ri(UseAdd, RetVT, LHSReg, LHSIsKill, Imm, SetFlags, WantResult); - } + } else if (const auto *C = dyn_cast(RHS)) + if (C->isNullValue()) + ResultReg = emitAddSub_ri(UseAdd, RetVT, LHSReg, LHSIsKill, 0, SetFlags, + WantResult); + if (ResultReg) return ResultReg; -- cgit v1.2.3