(MOVBQZX x:(MOVBload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)
(MOVBQZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)
(MOVBQZX x:(MOVLload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVBload <v.Type> [off] {sym} ptr mem)

// gcWriteBarrier does NOT follow the Go ABI. It accepts the
// number of bytes of buffer needed in R11, and returns a pointer
// to the buffer space in R11.
// It clobbers FLAGS. It does not clobber any general-purpose registers,
// but may clobber others (e.g., SSE registers).
// Typical use would be, when doing *(CX+88) = AX
//     CMPL    $0, runtime.writeBarrier(SB)
//     JEQ     dowrite

(MFVSRD (FMOVDconst [c])) => (MOVDconst [int64(math.Float64bits(c))])

(MTVSRD x:(MOVDload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (FMOVDload [off] {sym} ptr mem)
(MFVSRD x:(FMOVDload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) => @x.Block (MOVDload [off] {sym} ptr mem)

// Rules for MOV* or FMOV* ops determine when indexed (MOV*loadidx or MOV*storeidx)

	return nil // too far away
}

// clobber invalidates values. Returns true.
// clobber is used by rewrite rules to:
//
//	A) make sure the values are really dead and never used again.
//	B) decrement use counts of the values' args.
func clobber(vv ...*Value) bool {
	for _, v := range vv {
		v.reset(OpInvalid)
		// Note: leave v.Block intact.  The Block field is used after clobber.
	}
	return true
}

		// It saves all GP registers if necessary,
		// but clobbers R30 (LR) because it's a call.
		// R16 and R17 may be clobbered by linker trampoline.
		// Returns a pointer to a write barrier buffer in R25.
		{name: "LoweredWB", argLength: 1, reg: regInfo{clobbers: (callerSave &^ gpg) | buildReg("R16 R17 R30"), outputs: []regMask{buildReg("R25")}}, clobberFlags: true, aux: "Int64"},

	}

	// Handle any register clobbering. Call operations, for example,
	// clobber all registers even though they don't explicitly write to
	// them.
	clobbers := uint64(opcodeTable[v.Op].reg.clobbers)
	for {
		if clobbers == 0 {
			break
		}
		reg := uint8(bits.TrailingZeros64(clobbers))
		clobbers &^= 1 << reg

		for _, slot := range locs.registers[reg] {
			if state.loggingLevel > 1 {

	LXVD2X (R16)(CPOOL), P1
	LXVD2X (R0)(CPOOL), P0

	CALL p256MulInternal<>(SB)

	MOVD	n+16(FP), N
	ADD	$-1, N
	CMP	$0, N
	BEQ	done
	MOVD	N, n+16(FP)	// Save counter to avoid clobber
	VOR	T0, T0, X0
	VOR	T1, T1, X1
	BR	sqrLoop

done:
	MOVD $p256mul<>+0x00(SB), CPOOL

	XXPERMDI T0, T0, $2, T0
	XXPERMDI T1, T1, $2, T1
	STXVD2X T0, (R0)(res_ptr)

						// pointer in R2. Calls into a Go symbol preserve R2. No call stub is needed.
					} else {
						// This caller has a TOC pointer. The callee might clobber it. R2 needs to be saved
						// and restored.
						if sym, firstUse := genstub(ctxt, ldr, r, i, s, STUB_TOC); firstUse {
							stubs = append(stubs, sym)
						}
					}
				}

		m.mask = 1
	} else {
		m.mask = m.mask << 1
	}
	m.index++
}

// clobberdeadPtr is a special value that is used by the compiler to
// clobber dead stack slots, when -clobberdead flag is set.
const clobberdeadPtr = uintptr(0xdeaddead | 0xdeaddead<<((^uintptr(0)>>63)*32))

// badPointer throws bad pointer in heap panic.

              // Mimic
              // "if (!map.containsKey(key)) ...
              // else return map.get(key);
              return entryValue;
            } else {
              // clobber existing entry, count remains unchanged
              ++modCount;
              setValue(e, value);
              return entryValue;
            }
          }
        }