Class: Rucc::Node

Inherits:
Object
  • Object
show all
Extended by:
Conv
Defined in:
lib/rucc/node.rb,
lib/rucc/node/conv.rb

Overview

AST node

Defined Under Namespace

Modules: Conv

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Conv

conv

Constructor Details

#initialize(kind, ty: nil, ival: nil, fval: nil, flabel: nil, varname: nil, loff: nil, lvarinit: nil, glabel: nil, left: nil, right: nil, operand: nil, fname: nil, args: nil, ftype: nil, fptr: nil, params: nil, localvars: nil, body: nil, sval: nil, slabel: nil, declvar: nil, declinit: nil, initval: nil, initoff: nil, totype: nil, cond: nil, thn: nil, els: nil, label: nil, newlabel: nil, retval: nil, stmts: nil, struct: nil, field: nil, fieldtype: nil) ⇒ Node

Returns a new instance of Node.

Parameters:

  • kind (AST)
  • ty (Type) (defaults to: nil) 


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# File 'lib/rucc/node.rb', line 36

def initialize(kind,
               ty: nil,
               ival: nil,                               # Integer
               fval: nil, flabel: nil,                  # Float or double
               varname: nil,                            # Local/global variable
               loff: nil, lvarinit: nil,                # Local variable
               glabel: nil,                             # Global variable
               left: nil, right: nil,                   # Binary operator
               operand: nil,                            # Unary operator
               fname: nil,                              # Function call or function declaration
               args: nil, ftype: nil,                   # Function call
               fptr: nil,                               # Function pointer or function designator
               params: nil, localvars: nil, body: nil,  # Function declaration
               sval: nil, slabel: nil,                  # String
               declvar: nil, declinit: nil,             # Declaration
               initval: nil, initoff: nil, totype: nil, # Initializer
               cond: nil, thn: nil, els: nil,           # If statement or ternary operator
               label: nil, newlabel: nil,               # Goto and label
               retval: nil,                             # Return statement
               stmts: nil,                              # Compound statement
               struct: nil, field: nil, fieldtype: nil  # Struct reference
               )
  @kind = kind
  @ty = ty
  @ival = ival                                             # Integer
  @fval = fval; @flabel = flabel                           # Float or double
  @varname = varname                                       # Local/global variable
  @loff = loff; @lvarinit = lvarinit                       # Local variable
  @glabel = glabel                                         # Global variable
  @left = left; @right = right                             # Binary operator
  @operand = operand                                       # Unary operator
  @fname = fname                                           # Function call or function declaration
  @args = args; @ftype = ftype                             # Function call
  @fptr = fptr                                             # Function pointer or function designator
  @params = params; @localvars = localvars; @body = body   # Function declaration
  @sval = sval; @slabel = slabel                           # String
  @declvar = declvar; @declinit = declinit                 # Declaration
  @initval = initval; @initoff = initoff; @totype = totype # Initializer
  @cond = cond; @thn = thn; @els = els                     # If statement or ternary operator
  @label = label; @newlabel = newlabel                     # Goto and label
  @retval = retval                                         # Return statement
  @stmts = stmts                                           # Compound statement
  @struct = struct; @field = field; @fieldtype = fieldtype # Struct reference
end

Instance Attribute Details

#args ⇒ Object (readonly)

Returns the value of attribute args.



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# File 'lib/rucc/node.rb', line 80

def args
  @args
end

#body ⇒ Object (readonly)

Returns the value of attribute body.



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# File 'lib/rucc/node.rb', line 80

def body
  @body
end

#cond ⇒ Object (readonly)

Returns the value of attribute cond.



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# File 'lib/rucc/node.rb', line 80

def cond
  @cond
end

#declinit ⇒ Object (readonly)

Returns the value of attribute declinit.



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# File 'lib/rucc/node.rb', line 80

def declinit
  @declinit
end

#declvar ⇒ Object (readonly)

Returns the value of attribute declvar.



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# File 'lib/rucc/node.rb', line 80

def declvar
  @declvar
end

#els ⇒ Object (readonly)

Returns the value of attribute els.



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# File 'lib/rucc/node.rb', line 80

def els
  @els
end

#field ⇒ Object (readonly)

Returns the value of attribute field.



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# File 'lib/rucc/node.rb', line 80

def field
  @field
end

#fieldtype ⇒ Object (readonly)

Returns the value of attribute fieldtype.



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# File 'lib/rucc/node.rb', line 80

def fieldtype
  @fieldtype
end

#flabel ⇒ Object

Returns the value of attribute flabel.



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# File 'lib/rucc/node.rb', line 80

def flabel
  @flabel
end

#fname ⇒ Object (readonly)

Returns the value of attribute fname.



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# File 'lib/rucc/node.rb', line 80

def fname
  @fname
end

#fptr ⇒ Object (readonly)

Returns the value of attribute fptr.



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# File 'lib/rucc/node.rb', line 80

def fptr
  @fptr
end

#ftype ⇒ Object (readonly)

Returns the value of attribute ftype.



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# File 'lib/rucc/node.rb', line 80

def ftype
  @ftype
end

#fval ⇒ Object (readonly)

Returns the value of attribute fval.



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# File 'lib/rucc/node.rb', line 80

def fval
  @fval
end

#glabel ⇒ Object (readonly)

Returns the value of attribute glabel.



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# File 'lib/rucc/node.rb', line 80

def glabel
  @glabel
end

#initoff ⇒ Object (readonly)

Returns the value of attribute initoff.



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# File 'lib/rucc/node.rb', line 80

def initoff
  @initoff
end

#initval ⇒ Object (readonly)

Returns the value of attribute initval.



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# File 'lib/rucc/node.rb', line 80

def initval
  @initval
end

#ival ⇒ Object (readonly)

Returns the value of attribute ival.



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# File 'lib/rucc/node.rb', line 80

def ival
  @ival
end

#kind ⇒ Object (readonly)

Returns the value of attribute kind.



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# File 'lib/rucc/node.rb', line 80

def kind
  @kind
end

#label ⇒ Object (readonly)

Returns the value of attribute label.



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# File 'lib/rucc/node.rb', line 80

def label
  @label
end

#left ⇒ Object (readonly)

Returns the value of attribute left.



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# File 'lib/rucc/node.rb', line 80

def left
  @left
end

#localvars ⇒ Object (readonly)

Returns the value of attribute localvars.



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# File 'lib/rucc/node.rb', line 80

def localvars
  @localvars
end

#loff ⇒ Object

Returns the value of attribute loff.



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# File 'lib/rucc/node.rb', line 80

def loff
  @loff
end

#lvarinit ⇒ Object

Returns the value of attribute lvarinit.



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# File 'lib/rucc/node.rb', line 80

def lvarinit
  @lvarinit
end

#newlabel ⇒ Object

Returns the value of attribute newlabel.



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# File 'lib/rucc/node.rb', line 80

def newlabel
  @newlabel
end

#operand ⇒ Object (readonly)

Returns the value of attribute operand.



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# File 'lib/rucc/node.rb', line 80

def operand
  @operand
end

#params ⇒ Object (readonly)

Returns the value of attribute params.



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# File 'lib/rucc/node.rb', line 80

def params
  @params
end

#retval ⇒ Object (readonly)

Returns the value of attribute retval.



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# File 'lib/rucc/node.rb', line 80

def retval
  @retval
end

#right ⇒ Object (readonly)

Returns the value of attribute right.



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# File 'lib/rucc/node.rb', line 80

def right
  @right
end

#slabel ⇒ Object

Returns the value of attribute slabel.



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# File 'lib/rucc/node.rb', line 80

def slabel
  @slabel
end

#stmts ⇒ Object (readonly)

Returns the value of attribute stmts.



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# File 'lib/rucc/node.rb', line 80

def stmts
  @stmts
end

#struct ⇒ Object (readonly)

Returns the value of attribute struct.



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# File 'lib/rucc/node.rb', line 80

def struct
  @struct
end

#sval ⇒ Object (readonly)

Returns the value of attribute sval.



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# File 'lib/rucc/node.rb', line 80

def sval
  @sval
end

#thn ⇒ Object (readonly)

Returns the value of attribute thn.



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# File 'lib/rucc/node.rb', line 80

def thn
  @thn
end

#totype ⇒ Object (readonly)

Returns the value of attribute totype.



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# File 'lib/rucc/node.rb', line 80

def totype
  @totype
end

#ty ⇒ Object

Returns the value of attribute ty.



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# File 'lib/rucc/node.rb', line 80

def ty
  @ty
end

#varname ⇒ Object (readonly)

Returns the value of attribute varname.



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# File 'lib/rucc/node.rb', line 80

def varname
  @varname
end

Class Method Details

.ast_binop(ty, kind, left, right) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 303

def ast_binop(ty, kind, left, right)
  Node.new(kind,
           ty:    ty,
           left:  left,
           right: right)
end

.ast_compound_stmt(stmts) ⇒ Node

Parameters:

  • stmts (Array)

Returns:



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# File 'lib/rucc/node.rb', line 465

def ast_compound_stmt(stmts)
  Node.new(AST::COMPOUND_STMT, stmts: stmts)
end

.ast_computed_goto(expr) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 424

def ast_computed_goto(expr)
  Node.new(AST::COMPUTED_GOTO,
           operand: expr)
end

.ast_conv(totype, val) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 438

def ast_conv(totype, val)
  Node.new(AST::CONV,
           ty:      totype,
           operand: val)
end

.ast_decl(var, init) ⇒ Object

Parameters:

  • var (Node)
  • init (Array) 


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# File 'lib/rucc/node.rb', line 446

def ast_decl(var, init)
  Node.new(AST::DECL,
           declvar:  var,
           declinit: init)
end

.ast_dest(label) ⇒ Node

Parameters:

  • label (String)

Returns:



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# File 'lib/rucc/node.rb', line 394

def ast_dest(label)
  Node.new(AST::LABEL,
           label: label,
           newlabel: label)
end

.ast_floattype(ty, val) ⇒ Node

Parameters:

  • ty (Type)
  • val (Double)

Returns:



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# File 'lib/rucc/node.rb', line 214

def ast_floattype(ty, val)
  Node.new(AST::LITERAL,
           ty: ty,
           fval: val)
end

.ast_func(ty, fname, params, body, localvars) ⇒ Node

Parameters:

  • ty (Type)
  • fname (String)
  • params (Array)
  • body (Node)
  • localvars (Array)

Returns:



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# File 'lib/rucc/node.rb', line 248

def ast_func(ty, fname, params, body, localvars)
  Node.new(AST::FUNC,
           ty:        ty,
           fname:     fname,
           params:    params,
           localvars: localvars,
           body:      body)
end

.ast_funcall(ftype, fname, args) ⇒ Node

Parameters:

  • ftype (Type)
  • fname (String)
  • args (Array)

Returns:



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# File 'lib/rucc/node.rb', line 281

def ast_funcall(ftype, fname, args)
  Node.new(AST::FUNCALL,
           ty:    ftype.rettype,
           fname: fname,
           args:  args,
           ftype: ftype)
end

.ast_funcdesg(ty, fname) ⇒ Object

Parameters:

  • ty (Type)
  • fname (String) 


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# File 'lib/rucc/node.rb', line 271

def ast_funcdesg(ty, fname)
  Node.new(AST::FUNCDESG,
           ty: ty,
           fname: fname)
end

.ast_funcptr_call(fptr, args) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 260

def ast_funcptr_call(fptr, args)
  Util.assert!{ fptr.ty.kind == Kind::PTR }
  Util.assert!{ fptr.ty.ptr.kind == Kind::FUNC }
  Node.new(AST::FUNCPTR_CALL,
           ty:   fptr.ty.ptr.rettype,
           fptr: fptr,
           args: args)
end

.ast_goto(label) ⇒ Node

Parameters:

  • label (String)

Returns:



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# File 'lib/rucc/node.rb', line 417

def ast_goto(label)
  Node.new(AST::GOTO,
           label: label)
end

.ast_gvar(ty, name, globalenv) ⇒ Object

Parameters:

  • ty (Type)
  • name (String)
  • globalenv (RMap) 


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# File 'lib/rucc/node.rb', line 508

def ast_gvar(ty, name, globalenv)
  r = Node.new(AST::GVAR, ty: ty, varname: name, glabel: name)
  globalenv[name] = r
  r
end

.ast_if(cond, thn, els) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 366

def ast_if(cond, thn, els)
  Node.new(AST::IF,
           cond: cond,
           thn: thn,
           els: els)
end

.ast_init(val, totype, off) ⇒ Node

Parameters:

  • val (Node)
  • totype (Type)
  • off (Integer)

Returns:



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# File 'lib/rucc/node.rb', line 456

def ast_init(val, totype, off)
  Node.new(AST::INIT,
           initval: val,
           initoff: off,
           totype:  totype)
end

.ast_inttype(ty, val) ⇒ Object

Parameters:

  • ty (Type)
  • val (Integer) 


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# File 'lib/rucc/node.rb', line 206

def ast_inttype(ty, val)
  Util.assert!{ val.is_a?(Integer) }
  Node.new(AST::LITERAL, ty: ty, ival: val)
end

.ast_jump(label) ⇒ Node

Parameters:

  • label (String)

Returns:



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# File 'lib/rucc/node.rb', line 409

def ast_jump(label)
  Node.new(AST::GOTO,
           label: label,
           newlabel: label)
end

.ast_label(label) ⇒ Node

Parameters:

  • label (String)

Returns:



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# File 'lib/rucc/node.rb', line 388

def ast_label(label)
  Node.new(AST::LABEL, label: label)
end

.ast_label_addr(label) ⇒ Object

Parameters:

  • label (String) 


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# File 'lib/rucc/node.rb', line 401

def ast_label_addr(label)
  Node.new(OP::LABEL_ADDR,
           ty:    Type.make_ptr_type(Type::VOID),
           label: label)
end

.ast_lvar(ty, name, localenv, localvars) ⇒ Node

Parameters:

  • ty (Type)
  • name (String)
  • localenv (RMap)
  • localvars (Array)

Returns:



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# File 'lib/rucc/node.rb', line 494

def ast_lvar(ty, name, localenv, localvars)
  r = Node.new(AST::LVAR, ty: ty, varname: name)
  if localenv
    localenv[name] = r
  end
  if localvars
    localvars.push(r)
  end
  r
end

.ast_return(retval) ⇒ Object

Parameters:

  • retval (Node, NilClass) 


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# File 'lib/rucc/node.rb', line 430

def ast_return(retval)
  Node.new(AST::RETURN,
           retval: retval)
end

.ast_static_lvar(ty, name, localenv, glabel) ⇒ String

Parameters:

  • ty (Type)
  • name (String)
  • localenv (RMap)
  • glabel (String)

Returns:

  • (String) 


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# File 'lib/rucc/node.rb', line 519

def ast_static_lvar(ty, name, localenv, glabel)
  r = Node.new(AST::GVAR,
               ty: ty,
               varname: name,
               glabel: glabel)
  Util.assert!{ localenv }
  localenv[name] = r
  r
end

.ast_string(enc, str) ⇒ Object

Parameters:



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# File 'lib/rucc/node.rb', line 221

def ast_string(enc, str)
  case enc
  when ENC::NONE, ENC::UTF8
    ty = Type.make_array_type(Type::CHAR, str.bytes.size + 1)
    body = str
  when ENC::CHAR16
    b = UTF.to_utf16(str)
    ty = Type.make_array_type(Type::USHORT, (b.bytes.size / Type::USHORT.size) + 1)
    body = b + "\0"  # NOTE: Add only \0 (\0\0 - \0)
  when ENC::CHAR32, ENC::WCHAR
    b = UTF.to_utf32(str)
    ty = Type.make_array_type(Type::UINT, (b.bytes.size / Type::UINT.size) + 1)
    body = b + "\0\0\0"  # NOTE: Add only \0\0\0 (\0\0\0\0 - \0)
  else
    raise "Invalid encoding"
  end
  Node.new(AST::LITERAL,
           ty:   ty,
           sval: body)
end

.ast_struct_ref(ty, struct, name) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 482

def ast_struct_ref(ty, struct, name)
  Node.new(AST::STRUCT_REF,
           ty:     ty,
           struct: struct,
           field:  name)
end

.ast_ternary(ty, cond, thn, els) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 378

def ast_ternary(ty, cond, thn, els)
  Node.new(AST::TERNARY,
           ty:   ty,
           cond: cond,
           thn:  thn,
           els:  els)
end

.ast_typedef(ty, name, env) ⇒ Node

Parameters:

  • ty (Type)
  • name (String)

Returns:



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# File 'lib/rucc/node.rb', line 472

def ast_typedef(ty, name, env)
  r = Node.new(AST::TYPEDEF, ty: ty)
  env[name] = r
  r
end

.ast_uop(kind, ty, operand) ⇒ Object

Parameters:

  • kind (String)
  • ty (Type)
  • operand (Node) 


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# File 'lib/rucc/node.rb', line 292

def ast_uop(kind, ty, operand)
  Node.new(kind,
           ty:      ty,
           operand: operand)
end

.binop(op, lhs, rhs) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 314

def binop(op, lhs, rhs)
  if (lhs.ty.kind == Kind::PTR) && (rhs.ty.kind == Kind::PTR)
    if !valid_pointer_binop?(op)
      raise "internal pointer arith"
    end
    # C11 6.5.6.9: Pointer subtractions have type ptrdiff_t.
    if (op == '-'.freeze)
      return Node.ast_binop(Type::LONG, op, lhs, rhs)
    end
    # C11 6.5.8.6, 6.5.9.3: Pointer comparisons have type int.
    return Node.ast_binop(Type::INT, op, lhs, rhs);
  end

  # NOTE: Set pointer node as left
  if lhs.ty.kind == Kind::PTR
    return Node.ast_binop(lhs.ty, op, lhs, rhs)
  end
  if rhs.ty.kind == Kind::PTR
    return Node.ast_binop(rhs.ty, op, rhs, lhs)
  end

  Util.assert!{ Type.is_arithtype(lhs.ty) }
  Util.assert!{ Type.is_arithtype(rhs.ty) }
  r = Type.usual_arith_conv(lhs.ty, rhs.ty)
  Node.ast_binop(r, op, wrap(r, lhs), wrap(r, rhs))
end

.node_or_nil_to_s(node) ⇒ Object

Parameters:

  • node (Node, NilClass) 


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# File 'lib/rucc/node.rb', line 199

def node_or_nil_to_s(node)
  return '(nil)' if node.nil?
  node.to_s
end

.valid_pointer_binop?(op) ⇒ Boolean

Parameters:

Returns:

  • (Boolean) 


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# File 'lib/rucc/node.rb', line 343

def valid_pointer_binop?(op)
  case op
  when '-', '<', '>', OP::EQ, OP::NE, OP::GE, OP::LE
    return true
  else
    return false
  end
end

.wrap(t, node) ⇒ Node

Parameters:

Returns:



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# File 'lib/rucc/node.rb', line 355

def wrap(t, node)
  if Type.same_arith_type(t, node.ty)
    return node
  end
  Node.ast_uop(AST::CONV, t, node)
end

Instance Method Details

#to_s ⇒ String

Returns:

  • (String) 


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# File 'lib/rucc/node.rb', line 103

def to_s
  case kind
  when AST::LITERAL
    case ty.kind
    when Kind::CHAR
      if    ival == "\n" then return "'\\n'"      # '\n'
      elsif ival == "\\" then return "'\\\\'"     # '\\'
      elsif ival == "\0" then return "'\\0'"      # '\0'
      else                    return "'#{ival.chr}'"  # cf. 'a'
      end
    when Kind::INT
      return ival.to_s
    when Kind::FLOAT, Kind::DOUBLE, Kind::LDOUBLE
      return fval.to_s
    when Kind::LONG, Kind::LLONG
      return "#{ival}L"
    when Kind::ARRAY  # Consider string literal
      return "\"#{Util.quote_cstring(sval)}\""
    else
      raise "internal error"
    end
  when AST::LABEL
    return "#{label}:"
  when AST::LVAR
    s = "lv=#{varname}"
    if lvarinit
      s << "(#{lvarinit})"
    end
    return s
  when  AST::GVAR
    return "gv=#{varname}"
  when AST::FUNCALL, AST::FUNCPTR_CALL
    return "(#{ty})#{kind == AST::FUNCALL ? fname : Node.node_or_nil_to_s(node)}(#{args.map { |arg| Node.node_or_nil_to_s(arg) }.join(",")})"
  when AST::FUNCDESG
    return "(funcdesg #{fname})"
  when AST::FUNC
    return "(#{ty})#{fname}(#{params.map { |param| "#{param.ty} #{Node.node_or_nil_to_s(param)}" }.join(",")})#{Node.node_or_nil_to_s(body)}"
  when AST::GOTO
    return "goto(#{label})"
  when AST::DECL
    s = "(decl #{declvar.ty} #{declvar.varname}"
    if declinit
      s << " #{declinit.join(" ")}"
    end
    s << ")"
    return s
  when AST::INIT
    return "#{initval}@#{initoff}"
  when AST::CONV
    return "(conv #{operand}=>#{ty})"
  when AST::IF
    s = "(if #{Node.node_or_nil_to_s(cond)} #{Node.node_or_nil_to_s(thn)}"
    if els
      s << " #{els}"
    end
    s << ")"
    return s
  when AST::TERNARY
    return "(? #{Node.node_or_nil_to_s(cond)} #{Node.node_or_nil_to_s(thn)} #{Node.node_or_nil_to_s(els)})"
  when AST::RETURN
    return "(return #{retval})"
  when AST::COMPOUND_STMT
    return "{#{stmts.map { |stmt| "#{stmt};" }.join}}"
  when AST::STRUCT_REF
    return "#{struct}.#{field}"
  when AST::ADDR            then return "(addr #{operand})"
  when AST::DEREF           then return "(deref #{operand})"
  when OP::SAL              then return "(<< #{left} #{right})"
  when OP::SAR, OP::SHR     then return "(>> #{left} #{right})"
  when OP::GE               then return "(>= #{left} #{right})"
  when OP::LE               then return "(<= #{left} #{right})"
  when OP::NE               then return "(!= #{left} #{right})"
  when OP::PRE_INC          then return "(pre++ #{operand})"
  when OP::PRE_DEC          then return "(pre-- #{operand})"
  when OP::POST_INC         then return "(post++ #{operand})"
  when OP::POST_DEC         then return "(post-- #{operand})"
  when OP::LOGAND           then return "(and #{left} #{right})"
  when OP::LOGOR            then return "(or #{left} #{right})"
  when '!'                  then return "(! #{operand})"
  when '&'                  then return "(& #{left} #{right})"
  when '|'                  then return "(| #{left} #{right})"
  when OP::CAST
    return "((#{operand.ty})=>(#{ty}) #{operand})"
  when OP::LABEL_ADDR
    return "&&#{label}"
  when OP::EQ
    return "(== #{left} #{right})"
  else
    return "(#{kind} #{left} #{right})"
  end

  raise "Must not reach here!"
end