Strictness in data declaration not matched in assembler?

[Tyson Whitehead]

Consider the following code

data Data = Data { unData :: !Int }

func :: Data -> Int
func x = case unData x of
           1 -> 2
           _ -> 0

Compiling with GHC 6.8.2 gives the following stg code

Main.func =
    \r [x_slg]
        case x_slg of tpl_slx {
          Main.Data ipv_slj ->
              case ipv_slj of wild_sly {
                GHC.Base.I# ds_slm ->
                    case ds_slm of ds1_slz {
                      __DEFAULT -> Main.lvl1;
                      1 -> Main.lvl;
                    };
              };
        };

The native code generator turns it into the following x86_64 assembler

Main_func_info:
        leaq -8(%rbp),%rax
        cmpq %r14,%rax
        jb .LcnU
        movq %rsi,%rbx
        movq $sni_info,-8(%rbp)
        addq $-8,%rbp
        testq $7,%rbx
        jne sni_info
        jmp *(%rbx)
.LcnU:
        movl $Main_func_closure,%ebx
        jmp *-8(%r13)

sni_info:
        movq 7(%rbx),%rbx
        movq $snj_info,(%rbp)
        testq $7,%rbx
        jne snj_info
        jmp *(%rbx)

snj_info:
        cmpq $1,7(%rbx)
        jne .LcnE
        movl $Main_lvl_closure+1,%ebx
        addq $8,%rbp
        jmp *(%rbp)
.LcnE:
        movl $Main_lvl1_closure+1,%ebx
        addq $8,%rbp
        jmp *(%rbp)

It seems to me that the !Int member of the Data constructor is being treated 
like it might be a thunk in sni_info (i.e., the whole "testq $7,%rbx" thing).

Isn't this unnecessary as the "!" strictness flag means the Int argument must 
be forced by the Data constructor before being captured?

Thanks! -Tyson
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