zircon/kernel/lib/fixed_point/include/lib/fixed_point_debug.h

// Copyright 2016 The Fuchsia Authors
// Copyright (c) 2013, Google Inc. All rights reserved.
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT

#ifndef ZIRCON_KERNEL_LIB_FIXED_POINT_INCLUDE_LIB_FIXED_POINT_DEBUG_H_
#define ZIRCON_KERNEL_LIB_FIXED_POINT_INCLUDE_LIB_FIXED_POINT_DEBUG_H_

static inline const char* fpd_shift_prefix_32(int shift) {
  switch (shift) {
    case 32:
      return "";
    case 0:
      return "         ";
    case -32:
      return "                0.";
    case -64:
      return "                0.00000000 ";
    default:
      return "???";
  }
}

static inline const char* fpd_shift_prefix_64(int shift) {
  switch (shift) {
    case 32:
      return "";
    case 0:
      return "         ";
    case -32:
      return "                  ";
    case -64:
      return "                         0.";
    default:
      return "???";
  }
}

static inline const char* fpd_shift_suffix(int shift) {
  switch (shift) {
    case 32:
      return " 00000000                  ";
    case 0:
      return "                  ";
    case -32:
      return "         ";
    case -64:
      return "";
    default:
      return "???";
  }
}

static inline void debug_mul_u32_u32(uint32_t a, uint32_t b, int a_shift, int b_shift,
                                     uint64_t ret) {
#if DEBUG_FIXED_POINT
  TRACEF("         %s%08x%s * %s%08x%s = %s%08x%s%08x%s\n", fpd_shift_prefix_32(a_shift), a,
         fpd_shift_suffix(a_shift), fpd_shift_prefix_32(b_shift), b, fpd_shift_suffix(b_shift),
         fpd_shift_prefix_64(a_shift + b_shift), (uint32_t)(ret >> 32),
         (a_shift + b_shift == -32) ? "." : " ", (uint32_t)ret,
         fpd_shift_suffix(a_shift + b_shift));
#endif
}

static inline void debug_u64_mul_u32_fp32_64(uint32_t a, struct fp_32_64 b, uint64_t res_0,
                                             uint32_t res_l32_32, uint64_t ret) {
#if DEBUG_FIXED_POINT
  TRACEF(
      "          %08x                   *          %08x.%08x %08x"
      " =          %08x %08x.%08x\n",
      a, b.l0, b.l32, b.l64, (uint32_t)(res_0 >> 32), (uint32_t)res_0, res_l32_32);
  TRACEF(
      "                                   "
      "                                      "
      "~=          %08x %08x\n",
      (uint32_t)(ret >> 32), (uint32_t)ret);
#endif
}

static inline void debug_u32_mul_u64_fp32_64(uint64_t a, struct fp_32_64 b, uint64_t res_l32,
                                             uint32_t ret) {
#if DEBUG_FIXED_POINT
  TRACEF(
      "%08x %08x                   *          %08x.%08x %08x"
      " =                   %08x.%08x\n",
      (uint32_t)(a >> 32), (uint32_t)a, b.l0, b.l32, b.l64, (uint32_t)(res_l32 >> 32),
      (uint32_t)res_l32);
  TRACEF(
      "                                   "
      "                                      "
      "~=                   %08x\n",
      ret);
#endif
}

static inline void debug_u64_mul_u64_fp32_64(uint64_t a, struct fp_32_64 b, uint64_t res_0,
                                             uint32_t res_l32_32, uint64_t ret) {
#if DEBUG_FIXED_POINT
  TRACEF(
      "%08x %08x                   *          %08x.%08x %08x"
      " =          %08x %08x.%08x\n",
      (uint32_t)(a >> 32), (uint32_t)a, b.l0, b.l32, b.l64, (uint32_t)(res_0 >> 32),
      (uint32_t)res_0, res_l32_32);
  TRACEF(
      "                                   "
      "                                      "
      "~=          %08x %08x\n",
      (uint32_t)(ret >> 32), (uint32_t)ret);
#endif
}

#endif  // ZIRCON_KERNEL_LIB_FIXED_POINT_INCLUDE_LIB_FIXED_POINT_DEBUG_H_