diff options
| -rw-r--r-- | lib/compiler/src/beam_ssa_opt.erl | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/lib/compiler/src/beam_ssa_opt.erl b/lib/compiler/src/beam_ssa_opt.erl index e528bb4dfb..47b9ef28d8 100644 --- a/lib/compiler/src/beam_ssa_opt.erl +++ b/lib/compiler/src/beam_ssa_opt.erl @@ -2003,8 +2003,16 @@ ssa_opt_sink({#st{ssa=Blocks0}=St, FuncDb}) -> %% Create a map with all variables that define get_tuple_element %% instructions. The variable name map to the block it is defined in. - Defs = maps:from_list(def_blocks(Linear)), + case def_blocks(Linear) of + [] -> + %% No get_tuple_element instructions, so there is nothing to do. + {St, FuncDb}; + [_|_]=Defs0 -> + Defs = maps:from_list(Defs0), + {do_ssa_opt_sink(Linear, Defs, St), FuncDb} + end. +do_ssa_opt_sink(Linear, Defs, #st{ssa=Blocks0}=St) -> %% Now find all the blocks that use variables defined by get_tuple_element %% instructions. Used = used_blocks(Linear, Defs, []), @@ -2039,7 +2047,7 @@ ssa_opt_sink({#st{ssa=Blocks0}=St, FuncDb}) -> From = maps:get(V, Defs), move_defs(V, From, To, A) end, Blocks0, DefLoc), - {St#st{ssa=Blocks}, FuncDb}. + St#st{ssa=Blocks}. def_blocks([{L,#b_blk{is=Is}}|Bs]) -> def_blocks_is(Is, L, def_blocks(Bs)); |