runtime: rethrow/panic; llgo/ssa: DeferData; Null => Nil

internal/runtime/c/c.go

@@ -42,15 +42,30 @@ func Alloca(size uintptr) Pointer
 //go:linkname AllocaCStr llgo.allocaCStr
 func AllocaCStr(s string) *Char
 
+//go:linkname GoDeferData llgo.deferData
+func GoDeferData() Pointer
+
 //go:linkname Unreachable llgo.unreachable
 func Unreachable()
 
+//go:linkname AllocaSigjmpBuf llgo.sigjmpbuf
+func AllocaSigjmpBuf() Pointer
+
+//go:linkname Sigsetjmp llgo.sigsetjmp
+func Sigsetjmp(jb Pointer, savemask Int) Int
+
+//go:linkname Siglongjmp llgo.siglongjmp
+func Siglongjmp(jb Pointer, retval Int)
+
 //go:linkname Rand C.rand
 func Rand() Int
 
 //go:linkname Malloc C.malloc
 func Malloc(size uintptr) Pointer
 
+//go:linkname Free C.free
+func Free(ptr Pointer)
+
 //go:linkname Memcpy C.memcpy
 func Memcpy(dst, src Pointer, n uintptr) Pointer
 

internal/runtime/z_rt.go

@@ -19,6 +19,7 @@ package runtime
 import (
 	"unsafe"
 
+	"github.com/goplus/llgo/c/pthread"
 	"github.com/goplus/llgo/internal/abi"
 	"github.com/goplus/llgo/internal/runtime/c"
 )
@@ -27,19 +28,43 @@ import (
 
 // Defer presents defer statements in a function.
 type Defer struct {
-	Addr unsafe.Pointer
+	Addr unsafe.Pointer // sigjmpbuf
 	Bits uintptr
 	Link *Defer
 	Rund int // index of RunDefers
 }
 
-// -----------------------------------------------------------------------------
+// Panic panics with a value.
+func Panic(v Eface) {
+	ptr := c.Malloc(unsafe.Sizeof(v))
+	*(*Eface)(ptr) = v
+	excepKey.Set(ptr)
 
-// Zeroinit initializes memory to zero.
-func Zeroinit(p unsafe.Pointer, size uintptr) unsafe.Pointer {
-	return c.Memset(p, 0, size)
+	Rethrow((*Defer)(c.GoDeferData()))
 }
 
+// Rethrow rethrows a panic.
+func Rethrow(link *Defer) {
+	if link == nil {
+		ptr := excepKey.Get()
+		TracePanic(*(*Eface)(ptr))
+		c.Free(ptr)
+		c.Unreachable()
+	} else {
+		c.Siglongjmp(link.Addr, 1)
+	}
+}
+
+var (
+	excepKey pthread.Key
+)
+
+func init() {
+	excepKey.Create(nil)
+}
+
+// -----------------------------------------------------------------------------
+
 // TracePanic prints panic message.
 func TracePanic(v Eface) {
 	kind := v._type.Kind()
@@ -56,3 +81,10 @@ func stringTracef(fp c.FilePtr, format *c.Char, s String) {
 }
 
 // -----------------------------------------------------------------------------
+
+// Zeroinit initializes memory to zero.
+func Zeroinit(p unsafe.Pointer, size uintptr) unsafe.Pointer {
+	return c.Memset(p, 0, size)
+}
+
+// -----------------------------------------------------------------------------