[LLVMdev] Remove identical or redundant basic blocks?

[Heinz Riener]

Dear all,

after optimizing a small LLVM example program (i.e., with opt -O3), the 
resulting code contains several basic blocks, which I consider identical 
or redundant.  For instance,

return:                                           ; preds = %min.exit
   ret i32 0

bb15:                                             ; preds = %min.exit
   ret i32 0

or,

bb7.i:                                            ; preds = %bb1.i
   br label %bb3.i

bb9.i:                                            ; preds = %bb1.i
   br label %bb3.i

I think it is safe to remove the blocks bb7.i, bb9.i, bb15 while 
replacing each jump to bb15 with return and jumps to bb7.i, bb9.i with 
bb3.i.

Is there any opt pass I can apply to the code to merge or remove these 
blocks?

Heinz