Method createMakeMap

compiler/map.go:16–52

createMakeMap creates a new map object (runtime.hashmap) by allocating and initializing an appropriately sized object.

(expr *ssa.MakeMap)

// createMakeMap creates a new map object (runtime.hashmap) by allocating and
// initializing an appropriately sized object.
func (b *builder) createMakeMap(expr *ssa.MakeMap) (llvm.Value, error) {
	mapType := expr.Type().Underlying().(*types.Map)
	keyType := mapType.Key().Underlying()
	llvmValueType := b.getLLVMType(mapType.Elem().Underlying())
	var llvmKeyType llvm.Type
	var alg uint64
	if t, ok := keyType.(*types.Basic); ok && t.Info()&types.IsString != 0 {
		// String keys.
		llvmKeyType = b.getLLVMType(keyType)
		alg = uint64(tinygo.HashmapAlgorithmString)
	} else if hashmapIsBinaryKey(keyType) {
		// Trivially comparable keys.
		llvmKeyType = b.getLLVMType(keyType)
		alg = uint64(tinygo.HashmapAlgorithmBinary)
	} else {
		// All other keys. Implemented as map[interface{}]valueType for ease of
		// implementation.
		llvmKeyType = b.getLLVMRuntimeType("_interface")
		alg = uint64(tinygo.HashmapAlgorithmInterface)
	}
	keySize := b.targetData.TypeAllocSize(llvmKeyType)
	valueSize := b.targetData.TypeAllocSize(llvmValueType)
	llvmKeySize := llvm.ConstInt(b.uintptrType, keySize, false)
	llvmValueSize := llvm.ConstInt(b.uintptrType, valueSize, false)
	sizeHint := llvm.ConstInt(b.uintptrType, 8, false)
	algEnum := llvm.ConstInt(b.ctx.Int8Type(), alg, false)
	if expr.Reserve != nil {
		sizeHint = b.getValue(expr.Reserve, getPos(expr))
		var err error
		sizeHint, err = b.createConvert(expr.Reserve.Type(), types.Typ[types.Uintptr], sizeHint, expr.Pos())
		if err != nil {
			return llvm.Value{}, err
		}
	}
	hashmap := b.createRuntimeCall("hashmapMake", []llvm.Value{llvmKeySize, llvmValueSize, sizeHint, algEnum}, "")
	return hashmap, nil
}

// createMapLookup returns the value in a map. It calls a runtime function
// depending on the map key type to load the map value and its comma-ok value.