On 12/10/2010 02:17 PM, Liu wrote:
Hi all,
       I'm porting gcc to a MIPS-based DSP, I need write some builtin
func for some insns, but I can't find a doc., any one should help me?
Show me a example please? Thanks very much.

Liu.
Maybe you should at least implement the following two hooks:

TARGET_INIT_BUILTINS
      ---> to do some initialization

TARGET_EXPAND_BUILTIN
      ---> to expand builtin related tree to rtl
              I suggest you *define some UNSPEC rtl*,  like:
                 (define_insn "xxx"
                     [set (match_operand: .....)
                             (unspec:.... [...] UNSPEC_XXX)]
                  ......
                )

and then expand builtin tree to these rtl by calling the related *gen_xxx*

Suggest you to see s390's related hook implementation.

---
Best,
Wong

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