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| author | Björn Gustavsson <[email protected]> | 2018-09-04 14:16:16 +0200 |
|---|---|---|
| committer | Björn Gustavsson <[email protected]> | 2018-09-17 06:41:02 +0200 |
| commit | ec1f35c9f52be894ba295b9a48237020855e3c46 (patch) | |
| tree | f27e0062b987762529b784862bbc8dfa220d02af /lib | |
| parent | 354c64f4c0a568e7c4766228c21d7f5e276fd549 (diff) | |
| download | otp-ec1f35c9f52be894ba295b9a48237020855e3c46.tar.gz otp-ec1f35c9f52be894ba295b9a48237020855e3c46.tar.bz2 otp-ec1f35c9f52be894ba295b9a48237020855e3c46.zip | |
beam_ssa_codegen: Don't emit kill instructions before exit BIFs
Omitting `kill` instructions before BIFs that throw exceptions
will reduce the code size. This optimization supersedes the same
optimizations in beam_dead.
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/compiler/src/beam_ssa_codegen.erl | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/lib/compiler/src/beam_ssa_codegen.erl b/lib/compiler/src/beam_ssa_codegen.erl index becfe56b3a..40c2d8c07a 100644 --- a/lib/compiler/src/beam_ssa_codegen.erl +++ b/lib/compiler/src/beam_ssa_codegen.erl @@ -1270,21 +1270,29 @@ cg_call(#cg_set{anno=Anno,op=call,dst=Dst0,args=[#b_local{}=Func0|Args0]}, Call = build_call(call, Arity, {f,FuncLbl}, Context, Dst), Is = setup_args(Args, Anno, Context, St) ++ Line ++ Call, {Is,St}; -cg_call(#cg_set{anno=Anno,op=call,dst=Dst0,args=[#b_remote{}=Func0|Args0]}, +cg_call(#cg_set{anno=Anno0,op=call,dst=Dst0,args=[#b_remote{}=Func0|Args0]}, Where, Context, St) -> [Dst|Args] = beam_args([Dst0|Args0], St), #b_remote{mod=Mod0,name=Name0,arity=Arity} = Func0, case {beam_arg(Mod0, St),beam_arg(Name0, St)} of {{atom,Mod},{atom,Name}} -> Func = {extfunc,Mod,Name,Arity}, - Line = call_line(Where, Func, Anno), + Line = call_line(Where, Func, Anno0), Call = build_call(call_ext, Arity, Func, Context, Dst), + Anno = case erl_bifs:is_exit_bif(Mod, Name, Arity) of + true -> + %% There is no need to kill Y registers + %% before calling an exit BIF. + maps:remove(kill_yregs, Anno0); + false -> + Anno0 + end, Is = setup_args(Args, Anno, Context, St) ++ Line ++ Call, {Is,St}; {Mod,Name} -> Apply = build_apply(Arity, Context, Dst), - Is = setup_args(Args++[Mod,Name], Anno, Context, St) ++ - [line(Anno)] ++ Apply, + Is = setup_args(Args++[Mod,Name], Anno0, Context, St) ++ + [line(Anno0)] ++ Apply, {Is,St} end; cg_call(#cg_set{anno=Anno,op=call,dst=Dst0,args=Args0}, |