diff options
| -rw-r--r-- | lib/compiler/src/beam_ssa_type.erl | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/lib/compiler/src/beam_ssa_type.erl b/lib/compiler/src/beam_ssa_type.erl index a1c10c7a34..82371f4ba3 100644 --- a/lib/compiler/src/beam_ssa_type.erl +++ b/lib/compiler/src/beam_ssa_type.erl @@ -552,6 +552,17 @@ simplify(#b_set{op={bif,'=:='},args=[A1,_A2]=Args}=I, Ts) -> {true,#t_atom{elements=[true]}} -> %% Bool =:= true ==> Bool A1; + {true,#t_atom{elements=[false]}} -> + %% Bool =:= false ==> not Bool + %% + %% This will be further optimized to eliminate the + %% 'not', swapping the success and failure + %% branches in the br instruction. If A1 comes + %% from a type test (such as is_atom/1) or a + %% comparison operator (such as >=) that can be + %% translated to test instruction, this + %% optimization will eliminate one instruction. + simplify(I#b_set{op={bif,'not'},args=[A1]}, Ts); {_,_} -> eval_bif(I, Ts) end |