ir

type BasicBlock ¶

type BasicBlock struct {
	Label        BlockLabel
	Instructions []Instruction
	Terminator   *Terminator
}

BasicBlock is ordered in Graph.Blocks and contains instructions in source evaluation order.

type BlockLabel ¶

type BlockLabel string

BlockLabel is a stable, human-readable basic block identifier.

type Graph ¶

type Graph struct {
	Entry  BlockLabel
	Blocks []*BasicBlock
}

Graph is a flat SSA control-flow graph for one expression or function body.

func LowerSSA(node *ast.Node) (*Graph, error)

func LowerSSAFunction(params []Param, body *ast.Node) (*Graph, error)

func (graph *Graph) Validate() error

type IRCase ¶

type IRCase struct {
	Label     *ast.Node
	Body      *ast.Node
	IsDefault bool
}

type IRNode ¶

type IRNode struct {
	Kind  string
	Op    string
	Kids  []*ast.Node
	Cases []IRCase
	Type  ast.TypeInfo
}

func LowerShared(node *ast.Node) (*IRNode, bool)

type Instruction ¶

type Instruction struct {
	Result   Value
	Op       SSAOp
	Operands []ValueID
	Blocks   []BlockLabel
	Literal  string
	Symbol   string
}

Instruction defines exactly one SSA value. Blocks is populated for phi instructions and is positionally aligned with Operands.

type Param ¶

type Param struct {
	Name string
	Type ast.TypeInfo
}

Param describes one function parameter for LowerSSAFunction: the name it is referenced by within the function body, and its checker-inferred type.

type SSAOp ¶

type SSAOp string

SSAOp identifies a flat instruction operation.

const (
	OpConst         SSAOp = "const"
	OpSymbol        SSAOp = "symbol"
	OpPhi           SSAOp = "phi"
	OpUnit          SSAOp = "unit"
	OpAdd           SSAOp = "add"
	OpSubtract      SSAOp = "subtract"
	OpMultiply      SSAOp = "multiply"
	OpDivide        SSAOp = "divide"
	OpLess          SSAOp = "less"
	OpGreater       SSAOp = "greater"
	OpLessEqual     SSAOp = "less_equal"
	OpGreaterEqual  SSAOp = "greater_equal"
	OpEqual         SSAOp = "equal"
	OpNotEqual      SSAOp = "not_equal"
	OpAnd           SSAOp = "and"
	OpOr            SSAOp = "or"
	OpSet           SSAOp = "set"
	OpCall          SSAOp = "call"
	OpParam         SSAOp = "param"
	OpList          SSAOp = "list"
	OpDict          SSAOp = "dict"
	OpMapGet        SSAOp = "map_get"
	OpListGet       SSAOp = "list_get"
	OpPrint         SSAOp = "print"
	OpToInt         SSAOp = "to_int"
	OpToFloat       SSAOp = "to_float"
	OpToString      SSAOp = "to_string"
	OpBytesToString SSAOp = "bytes_to_string"
)

type SourceLocation ¶

type SourceLocation struct {
	Filename string
	Line     int
	Column   int
}

SourceLocation retains enough of the source AST location for diagnostics.

type Terminator ¶

type Terminator struct {
	Kind        TerminatorKind
	Cond        ValueID
	Value       ValueID
	Target      BlockLabel
	TrueTarget  BlockLabel
	FalseTarget BlockLabel
	Source      SourceLocation
}

Terminator is an explicit control-flow edge. Value is optional for a void return and Cond is required for a branch.

type TerminatorKind ¶

type TerminatorKind string

TerminatorKind identifies the control transfer ending a basic block.

const (
	TermJump   TerminatorKind = "jump"
	TermBranch TerminatorKind = "branch"
	TermReturn TerminatorKind = "return"
)

type Value ¶

type Value struct {
	ID     ValueID
	Type   ast.TypeInfo
	Source SourceLocation
}

Value is the result defined by an instruction.

type ValueID ¶

type ValueID uint64

ValueID is a graph-wide identifier for one SSA definition. The zero value is reserved for terminators and expressions that do not produce a value.