divi.S 1.2 KB

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  1. ;; SPDX-License-Identifier: GPL-2.0-or-later
  2. ;; Copyright 2010 Free Software Foundation, Inc.
  3. ;; Contributed by Bernd Schmidt <bernds@codesourcery.com>.
  4. ;;
  5. #include <linux/linkage.h>
  6. ;; ABI considerations for the divide functions
  7. ;; The following registers are call-used:
  8. ;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5
  9. ;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4
  10. ;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4
  11. ;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4
  12. ;;
  13. ;; In our implementation, divu and remu are leaf functions,
  14. ;; while both divi and remi call into divu.
  15. ;; A0 is not clobbered by any of the functions.
  16. ;; divu does not clobber B2 either, which is taken advantage of
  17. ;; in remi.
  18. ;; divi uses B5 to hold the original return address during
  19. ;; the call to divu.
  20. ;; remi uses B2 and A5 to hold the input values during the
  21. ;; call to divu. It stores B3 in on the stack.
  22. .text
  23. ENTRY(__c6xabi_divi)
  24. call .s2 __c6xabi_divu
  25. || mv .d2 B3, B5
  26. || cmpgt .l1 0, A4, A1
  27. || cmpgt .l2 0, B4, B1
  28. [A1] neg .l1 A4, A4
  29. || [B1] neg .l2 B4, B4
  30. || xor .s1x A1, B1, A1
  31. [A1] addkpc .s2 _divu_ret, B3, 4
  32. _divu_ret:
  33. neg .l1 A4, A4
  34. || mv .l2 B3,B5
  35. || ret .s2 B5
  36. nop 5
  37. ENDPROC(__c6xabi_divi)