WHIRL Gen 核心邏輯（Spin 2 whirl）

（就是獲取spin的每個node）

gs_t 就是 spin的單個AST node

使用gs_operand(list,0)獲取當前node的is_t，

使用 list = gs_operand(list,1)獲取下一個node

獲取node之后使用 WGEN_Expand_Top_Level_Decl (gs_t decl) 來展開莫個gs_t()

之后就是各種調用WGEN_Expand_Decl ，包括遞歸調用

中間可能出現:

——— ? Function ? ———?

WGEN_Expand_Function_Body

WGEN_Start_Function

WGEN_Handle_Named_Return_Value

Mark_Scopes_And_Labels

WGEN_Expand_Stmt

WGEN_Finish_Function

Pop_Current_Function_Decl

Push_Current_Function_Decl

—— ?Whirl ?———?

WGEN_Whirlify_Decl

WGEN_Initialize_Decl

——— ?Thunk ?———?

WGEN_Adjust_Thunk

WGEN_Generate_Thunk ?— For adjusting return or this pointer.

——— ?Symtab ———?

WN_st_idx()

ST_st_idx(const char *) ?string -> str_id / saving ?function name to symtab?

——— ?WN ———?

WN_Set_Call_Default_Flags

WN_Set_Call_Replace_By_Jump

WN_Ldid

WN_CreateParm(Mtype_comparison (arg_mtype), arg_wn,

? ? ? ? ? ? ? ? ? ? ? ? ? ?arg_ty, WN_PARM_BY_VALUE);

WN_kid = *** ? Set kid of WN

WN_Create (OPR_CALL, ret_mtype, MTYPE_V, nargs)

WN_st

WN_CreateReturn

WN_Stid

—— ? Statement. ———?

WGEN_Stmt_Append(wn, getsrcpos())

Mark_Scopes_And_Labels()

WGEN_Expand_Stmt

WGEN_GetLABEL

WGEN_Assembly_Alias

BT實測結果

frame #0: 0x0000000100070282 wgen`::WGEN_Expand_Decl(decl=0x0000000101800580, can_skip=YES) at wgen_decl.cxx:709

?frame #1: 0x000000010007b5dd wgen`::WGEN_Expand_Top_Level_Decl(top_level_decl=0x0000000101800580) at wgen_decl.cxx:5208

? ? frame #2: 0x0000000100002555 wgen`main(argc=3, argv=0x00007fff5fbffa88, envp=0x00007fff5fbffaa8) at main.c:362