Wrong lifting results for simple programs

[Qiuye-Hua]

I was trying retdec's ability to rise from ARM64 to C. Firstly I wrote the following (most simple) assembly code asmadd.s:

.arch armv8-a
.text
.global	asmadd
.type	asmadd, %function
asmadd:
	add	w0, w0, w1
	ret

The assembly and lifting are done by the following commands:

aarch64-linux-gnu-as asmadd.s -o asmadd.o
retdec-decompiler asmadd.o -a arm64

I was expecting the result to be something like:

int32_t asmadd(int32_t a, int32_t b)
{
    return a + b;
}

Instead, I got:

// Address range: 0x0 - 0x8
int32_t asmadd(int32_t a1) {
    int32_t result = a1; // 0x0
    bool v1; // 0x0
    if (false == !v1) {
        result = (int32_t)*(char *)12;
    }
    // 0x40008
    return result;
}

which is obviously wrong.

Is there something missing in the above steps? Or is there a way that I can "tell" RetDec how to do the lifting correctly?

---

BTW, here is the emitted LLVM IR. It seems that IR is wrong already.

source_filename = "test"
target datalayout = "e-p:32:32:32-f80:32:32"

define i32 @asmadd(i32 %arg1) local_unnamed_addr {
dec_label_pc_0:
  %0 = alloca i1
  %r0.0.reg2mem = alloca i32, !insn.addr !0
  %1 = load i1, i1* %0
  %2 = load i1, i1* %0
  %3 = load i1, i1* %0
  %.not = icmp ne i1 %2, true
  %4 = icmp ne i1 %3, %1, !insn.addr !1
  %or.cond = icmp eq i1 %4, %.not
  store i32 %arg1, i32* %r0.0.reg2mem, !insn.addr !0
  br i1 %or.cond, label %5, label %dec_label_pc_40008, !insn.addr !0

; <label>:5:                                      ; preds = %dec_label_pc_0
  %6 = load i8, i8* inttoptr (i32 12 to i8*), align 4, !insn.addr !1
  %7 = zext i8 %6 to i32, !insn.addr !1
  store i32 %7, i32* %r0.0.reg2mem, !insn.addr !1
  br label %dec_label_pc_40008, !insn.addr !1

dec_label_pc_40008:                               ; preds = %dec_label_pc_0, %5
  %r0.0.reload = load i32, i32* %r0.0.reg2mem
  ret i32 %r0.0.reload, !insn.addr !1

; uselistorder directives
  uselistorder i32* %r0.0.reg2mem, { 0, 2, 1 }
  uselistorder i1* %0, { 2, 1, 0 }
  uselistorder i32 1, { 1, 0 }
  uselistorder label %dec_label_pc_40008, { 1, 0 }
}

!0 = !{i64 0}
!1 = !{i64 4}