| // Copyright 2017 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package arm64asm |
| |
| func extract_bit(value, bit uint32) uint32 { |
| return (value >> bit) & 1 |
| } |
| |
| func bfxpreferred_4(sf, opc1, imms, immr uint32) bool { |
| if imms < immr { |
| return false |
| } |
| if (imms>>5 == sf) && (imms&0x1f == 0x1f) { |
| return false |
| } |
| if immr == 0 { |
| if sf == 0 && (imms == 7 || imms == 15) { |
| return false |
| } |
| if sf == 1 && opc1 == 0 && (imms == 7 || |
| imms == 15 || imms == 31) { |
| return false |
| } |
| } |
| return true |
| } |
| |
| func move_wide_preferred_4(sf, N, imms, immr uint32) bool { |
| if sf == 1 && N != 1 { |
| return false |
| } |
| if sf == 0 && !(N == 0 && ((imms>>5)&1) == 0) { |
| return false |
| } |
| if imms < 16 { |
| return (-immr)%16 <= (15 - imms) |
| } |
| width := uint32(32) |
| if sf == 1 { |
| width = uint32(64) |
| } |
| if imms >= (width - 15) { |
| return (immr % 16) <= (imms - (width - 15)) |
| } |
| return false |
| } |
| |
| type sys uint8 |
| |
| const ( |
| sys_AT sys = iota |
| sys_DC |
| sys_IC |
| sys_TLBI |
| sys_SYS |
| ) |
| |
| func sys_op_4(op1, crn, crm, op2 uint32) sys { |
| sysInst := sysInstFields{uint8(op1), uint8(crn), uint8(crm), uint8(op2)} |
| return sysInst.getType() |
| } |
| |
| func is_zero(x uint32) bool { |
| return x == 0 |
| } |
| |
| func is_ones_n16(x uint32) bool { |
| return x == 0xffff |
| } |
| |
| func bit_count(x uint32) uint8 { |
| var count uint8 |
| for count = 0; x > 0; x >>= 1 { |
| if (x & 1) == 1 { |
| count++ |
| } |
| } |
| return count |
| } |
