// NewBasicBlock returns a new basic block based on the given name, non-
// terminating instructions and terminator.
func NewBasicBlock(nameToken, insts, term interface{}) (*ir.BasicBlock, error) {
// Get label name.
var name string
switch nameToken := nameToken.(type) {
case *token.Token:
// Strip ":" suffix.
s, err := stripLabelSuffix(nameToken.Lit)
if err != nil {
return nil, errutil.Err(err)
}
name = s
case nil:
// Unnamed basic block.
default:
return nil, errutil.Newf("invalid basic block name type; expected *token.Token, got %T", nameToken)
}
if term, ok := term.(instruction.Terminator); ok {
switch insts := insts.(type) {
case []instruction.Instruction:
block := ir.NewBasicBlock(name)
block.SetInsts(insts)
block.SetTerm(term)
return block, nil
case nil:
block := ir.NewBasicBlock(name)
block.SetTerm(term)
return block, nil
default:
return nil, errutil.Newf("invalid non-terminating instructions type; expected []instruction.Instruction, got %T", insts)
}
}
return nil, errutil.Newf("invalid terminator type; expected instruction.Terminator, got %T", term)
}
// fixFunc replaces dummy values within the given function with their
// corresponding local variables.
func (m dummyMap) fixFunc(oldFunc *ir.Function) *ir.Function {
f := ir.NewFunction(oldFunc.Name(), oldFunc.Sig())
// Add mapping for basic blocks so they may be forward-referenced from
// instructions.
for _, oldBlock := range oldFunc.Blocks() {
name := oldBlock.Name()
block := ir.NewBasicBlock(name)
m.set(name, block)
}
for _, oldBlock := range oldFunc.Blocks() {
block := m.fixBlock(oldBlock)
f.AppendBlock(block)
}
if err := f.AssignIDs(); err != nil {
panic(errutil.Err(err))
}
return f
}