{name: "LoweredAtomicOr32", argLength: 3, reg: gpatomic, asm: "AMOORW", faultOnNilArg0: true, hasSideEffects: true},

		// Lowering pass-throughs
		{name: "LoweredNilCheck", argLength: 2, faultOnNilArg0: true, nilCheck: true, reg: regInfo{inputs: []regMask{gpspMask}}}, // arg0=ptr,arg1=mem, returns void.  Faults if ptr is nil.

		mem)

// Checks
(IsNonNil ...) => (SNEZ ...)
(IsInBounds ...) => (Less64U ...)
(IsSliceInBounds ...) => (Leq64U ...)

// Trivial lowering
(NilCheck ...) => (LoweredNilCheck ...)
(GetClosurePtr ...) => (LoweredGetClosurePtr ...)
(GetCallerSP ...) => (LoweredGetCallerSP ...)
(GetCallerPC ...) => (LoweredGetCallerPC ...)

// Write barrier.
(WB ...) => (LoweredWB ...)

		// See runtime/stubs.go for a more detailed discussion.
		{name: "LoweredGetCallerPC", reg: gp01, rematerializeable: true},

		//arg0=ptr,arg1=mem, returns void.  Faults if ptr is nil.
		{name: "LoweredNilCheck", argLength: 2, reg: regInfo{inputs: []regMask{gp | sp | sb}, clobbers: tmp}, clobberFlags: true, nilCheck: true, faultOnNilArg0: true},
		// Round ops to block fused-multiply-add extraction.

		// pseudo-ops
		{name: "LoweredNilCheck", argLength: 2, reg: regInfo{inputs: []regMask{gpg}}, nilCheck: true, faultOnNilArg0: true}, // panic if arg0 is nil.  arg1=mem.

(GetCallerPC ...) => (LoweredGetCallerPC ...)
(IsNonNil ptr) => (NotEqual (CMPconst [0] ptr))
(IsInBounds idx len) => (LessThan (CMPU idx len))
(IsSliceInBounds idx len) => (LessEqual (CMPU idx len))
(NilCheck ...) => (LoweredNilCheck ...)

// Write barrier.
(WB ...) => (LoweredWB ...)

// Publication barrier as intrinsic
(PubBarrier ...) => (LoweredPubBarrier ...)

// Miscellaneous
(IsNonNil p) => (SETNE (TESTQ p p))
(IsInBounds idx len) => (SETB (CMPQ idx len))
(IsSliceInBounds idx len) => (SETBE (CMPQ idx len))
(NilCheck ...) => (LoweredNilCheck ...)
(GetG mem) && v.Block.Func.OwnAux.Fn.ABI() != obj.ABIInternal => (LoweredGetG mem) // only lower in old ABI. in new ABI we have a G register.
(GetClosurePtr ...) => (LoweredGetClosurePtr ...)

		argLen:            1,
		rematerializeable: true,
		reg: regInfo{
			outputs: []outputInfo{
				{0, 239}, // AX CX DX BX BP SI DI
			},
		},
	},
	{
		name:           "LoweredNilCheck",
		argLen:         2,
		clobberFlags:   true,
		nilCheck:       true,
		faultOnNilArg0: true,
		reg: regInfo{
			inputs: []inputInfo{
				{0, 255}, // AX CX DX BX SP BP SI DI
			},
		},

// calls
(StaticCall  ...) => (CALLstatic  ...)
(ClosureCall ...) => (CALLclosure ...)
(InterCall   ...) => (CALLinter   ...)
(TailCall    ...) => (CALLtail    ...)

// checks
(NilCheck ...) => (LoweredNilCheck ...)
(IsNonNil ptr) => (NotEqual (CMPconst [0] ptr))
(IsInBounds      idx len) => (LessThanU  (CMP idx len))
(IsSliceInBounds idx len) => (LessEqualU (CMP idx len))

// pseudo-ops