support make string from byte slice

Author: douyixuan

Makefile

@@ -127,6 +127,7 @@ test/example:
 	${CELL} -d -t riscv tests/examples/helloworld.cell && ckb-debugger --bin helloworld | grep "hello world! 1"
 	${CELL} -t riscv tests/examples/table.cell && ckb-debugger --bin table
 	${CELL} -d -t riscv tests/examples/string.cell && ckb-debugger --bin string | grep "eq"
+	${CELL} -d -t riscv tests/examples/string-ctor.cell && ckb-debugger --bin string-ctor | grep "s=12"
 	${CELL} -d -t riscv tests/examples/strings.cell && ckb-debugger --bin strings | grep "aa-bb"
 	${CELL} -d -t riscv tests/examples/make-slice.cell && ckb-debugger --bin make-slice | grep "0422"
 	${CELL} -d -t riscv tests/examples/panic.cell && ckb-debugger --bin panic | grep "runtime panic: hah"

compiler/compiler/compiler.go

@@ -359,6 +359,8 @@ func (c *Compiler) compileValue(node parser.Node) value.Value {
 		return c.compileNegateBoolNode(v)
 	case *parser.InitializeSliceNode:
 		return c.compileInitializeSliceNode(v)
+	case *parser.InitializeStringWithSliceNode:
+		return c.compileInitializeStringWithSliceNode(v)
 	case *parser.SliceArrayNode:
 		src := c.compileValue(v.Val)
 

compiler/compiler/strings.go

@@ -0,0 +1,51 @@
+package compiler
+
+import (
+	"github.com/llir/llvm/ir/constant"
+	llvmTypes "github.com/llir/llvm/ir/types"
+	llvmValue "github.com/llir/llvm/ir/value"
+
+	"github.com/cell-labs/cell-script/compiler/compiler/internal"
+	"github.com/cell-labs/cell-script/compiler/compiler/internal/pointer"
+	"github.com/cell-labs/cell-script/compiler/compiler/name"
+	"github.com/cell-labs/cell-script/compiler/compiler/value"
+	"github.com/cell-labs/cell-script/compiler/parser"
+)
+
+func (c *Compiler) compileInitializeStringWithSliceNode(v *parser.InitializeStringWithSliceNode) value.Value {
+	sliceValue := c.compileValue(v.Items[0])
+	srcVal := internal.LoadIfVariable(c.contextBlock, sliceValue)
+	srcLen := c.contextBlock.NewExtractValue(srcVal, 0)
+	srcOff := c.contextBlock.NewExtractValue(srcVal, 2)
+	srcArr := c.contextBlock.NewExtractValue(srcVal, 3)
+	srcArrStartPtr := c.contextBlock.NewGetElementPtr(pointer.ElemType(srcArr), srcArr, srcOff)
+	length := c.contextBlock.NewSub(srcLen, srcOff)
+	// create new string
+	strVal := c.contextBlock.NewCall(c.osFuncs.Strndup.Value.(llvmValue.Named), srcArrStartPtr, length)
+	// construct a new string {i64, i8*}
+	sType, ok := c.packages["global"].GetPkgType("string", true)
+	if !ok {
+		panic("string type not found")
+	}
+	alloc := c.contextBlock.NewAlloca(sType.LLVM())
+
+	// Save length of the string
+	lenItem := c.contextBlock.NewGetElementPtr(pointer.ElemType(alloc), alloc, constant.NewInt(llvmTypes.I32, 0), constant.NewInt(llvmTypes.I32, 0))
+	lenItem.SetName(name.Var("len"))
+	if length.Type() != llvmTypes.I64 {
+		c.contextBlock.NewStore(c.contextBlock.NewZExt(length, i64.LLVM()), lenItem)
+	} else {
+		c.contextBlock.NewStore(length, lenItem)
+	}
+
+	// Save i8* version of string
+	strItem := c.contextBlock.NewGetElementPtr(pointer.ElemType(alloc), alloc, constant.NewInt(llvmTypes.I32, 0), constant.NewInt(llvmTypes.I32, 1))
+	strItem.SetName(name.Var("str"))
+	c.contextBlock.NewStore(strVal, strItem)
+
+	return value.Value{
+		Value:      c.contextBlock.NewLoad(pointer.ElemType(alloc), alloc),
+		Type:       sType,
+		IsVariable: false,
+	}
+}

compiler/parser/node.go

@@ -427,6 +427,15 @@ func (i InitializeStructNode) String() string {
 	return fmt.Sprintf("InitializeStructNode-%s{%+v}", i.Type, i.Items)
 }
 
+type InitializeStringWithSliceNode struct {
+	baseNode
+	Items []Node
+}
+
+func (i InitializeStringWithSliceNode) String() string {
+	return fmt.Sprintf("InitializeStringWithSliceNode-%s{%+v}", i.Items)
+}
+
 type DeVariadicSliceNode struct {
 	baseNode
 	Item Node

compiler/parser/parser.go

@@ -390,6 +390,12 @@ func (p *parser) parseOneWithOptions(withAheadParse, withArithAhead, withIdentif
 				} else {
 					panic("wrong argument for slice constructor")
 				}
+			case *SingleTypeNode:
+				if t.TypeName == "string" {
+					return &InitializeStringWithSliceNode{
+						Items: items,
+					}
+				}
 			default:
 				panic("not supported")
 			}

compiler/parser/walk.go

@@ -151,6 +151,10 @@ func Walk(v Visitor, node Node) (r Node) {
 		for i, a := range n.Items {
 			n.Items[i] = Walk(v, a)
 		}
+	case *InitializeStringWithSliceNode:
+		for i, a := range n.Items {
+			n.Items[i] = Walk(v, a)
+		}
 	case *ExternNode:
 		for _, fn := range n.FuncNodes {
 			Walk(v, fn)

tests/examples/string-ctor.cell

@@ -0,0 +1,13 @@
+import (
+	"debug"
+)
+
+func main() {
+	b := []byte{'1','2'}
+	s := make(string, b)
+	debug.Printf("s=%s",s)
+	s1 := make(string, b[0:1])
+	debug.Printf("%s",s1)
+	debug.Printf("s1=%s",s)
+	return 0
+}