// Compile receives the root node of the AST and generates code
// for the "main" function from it.
// Any type of Node is accepted, either a block representing the program
// or a single expression.
//
func Compile(root ast.Node, filename string) (res *FuncProto, err error) {
defer func() {
if r := recover(); r != nil {
if cerr, ok := r.(*CompileError); ok {
err = cerr
} else {
panic(r)
}
}
}()
var c compiler
c.filename = filename
c.mainFunc = newFuncProto(filename)
c.block = newCompilerBlock(c.mainFunc, kBlockContextFunc, nil)
root.Accept(&c, nil)
c.functionReturnGuard()
res = c.mainFunc
return
}
func (c *compiler) branchConditionHelper(cond, then, else_ ast.Node, reg int) {
ternaryData := exprdata{true, reg + 1, reg + 1}
cond.Accept(c, &ternaryData)
condr := ternaryData.regb
jmpInstr := c.emitAsBx(OpJmpfalse, condr, 0, c.lastLine)
thenLabel := c.newLabel()
ternaryData = exprdata{false, reg, reg}
then.Accept(c, &ternaryData)
c.modifyAsBx(jmpInstr, OpJmpfalse, condr, c.labelOffset(thenLabel))
if else_ != nil {
successInstr := c.emitAsBx(OpJmp, 0, 0, c.lastLine)
elseLabel := c.newLabel()
ternaryData = exprdata{false, reg, reg}
else_.Accept(c, &ternaryData)
c.modifyAsBx(successInstr, OpJmp, 0, c.labelOffset(elseLabel))
}
}
func SyntaxTree(root ast.Node, indentSize int) string {
v := prettyprinter{indentSize: indentSize}
root.Accept(&v, nil)
return v.buf.String()
}
