diff options
Diffstat (limited to 'lib/compiler/src/v3_codegen.erl')
| -rw-r--r-- | lib/compiler/src/v3_codegen.erl | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl index 7d0dd9b41a..84a1e185ea 100644 --- a/lib/compiler/src/v3_codegen.erl +++ b/lib/compiler/src/v3_codegen.erl @@ -1385,7 +1385,6 @@ catch_cg(C, {var,R}, Le, Vdb, Bef, St0) -> %% %% put_list for constructing a cons is an atomic instruction %% which can safely resuse one of the source registers as target. -%% Also binaries can reuse a source register as target. set_cg([{var,R}], {cons,Es}, Le, Vdb, Bef, St) -> [S1,S2] = cg_reg_args(Es, Bef), @@ -1395,10 +1394,23 @@ set_cg([{var,R}], {cons,Es}, Le, Vdb, Bef, St) -> {[{put_list,S1,S2,Ret}], Int1, St}; set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef, #cg{in_catch=InCatch, bfail=Bfail}=St) -> + %% At run-time, binaries are constructed in three stages: + %% 1) First the size of the binary is calculated. + %% 2) Then the binary is allocated. + %% 3) Then each field in the binary is constructed. + %% For simplicity, we use the target register to also hold the + %% size of the binary. Therefore the target register must *not* + %% be one of the source registers. + + %% First allocate the target register. Int0 = Bef#sr{reg=put_reg(R, Bef#sr.reg)}, Target = fetch_reg(R, Int0#sr.reg), - Fail = {f,Bfail}, + + %% Also allocate a scratch register for size calculations. Temp = find_scratch_reg(Int0#sr.reg), + + %% First generate the code that constructs each field. + Fail = {f,Bfail}, PutCode = cg_bin_put(Segs, Fail, Bef), {Sis,Int1} = case InCatch of @@ -1407,6 +1419,8 @@ set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef, end, MaxRegs = max_reg(Bef#sr.reg), Aft = clear_dead(Int1, Le#l.i, Vdb), + + %% Now generate the complete code for constructing the binary. Code = cg_binary(PutCode, Target, Temp, Fail, MaxRegs, Le#l.a), {Sis++Code,Aft,St}; set_cg([{var,R}], Con, Le, Vdb, Bef, St) -> @@ -1571,8 +1585,7 @@ cg_gen_binsize([], _, _, _, _, Acc) -> Acc. %% cg_bin_opt(Code0) -> Code %% Optimize the size calculations for binary construction. -cg_bin_opt([{move,Size,D},{bs_append,Fail,D,Extra,Regs0,U,Bin,Flags,D}|Is]) -> - Regs = cg_bo_newregs(Regs0, D), +cg_bin_opt([{move,Size,D},{bs_append,Fail,D,Extra,Regs,U,Bin,Flags,D}|Is]) -> cg_bin_opt([{bs_append,Fail,Size,Extra,Regs,U,Bin,Flags,D}|Is]); cg_bin_opt([{move,Size,D},{bs_private_append,Fail,D,U,Bin,Flags,D}|Is]) -> cg_bin_opt([{bs_private_append,Fail,Size,U,Bin,Flags,D}|Is]); @@ -1580,9 +1593,8 @@ cg_bin_opt([{move,{integer,0},D},{bs_add,_,[D,{integer,_}=S,1],Dst}|Is]) -> cg_bin_opt([{move,S,Dst}|Is]); cg_bin_opt([{move,{integer,0},D},{bs_add,Fail,[D,S,U],Dst}|Is]) -> cg_bin_opt([{bs_add,Fail,[{integer,0},S,U],Dst}|Is]); -cg_bin_opt([{move,{integer,Bytes},D},{Op,Fail,D,Extra,Regs0,Flags,D}|Is]) +cg_bin_opt([{move,{integer,Bytes},D},{Op,Fail,D,Extra,Regs,Flags,D}|Is]) when Op =:= bs_init2; Op =:= bs_init_bits -> - Regs = cg_bo_newregs(Regs0, D), cg_bin_opt([{Op,Fail,Bytes,Extra,Regs,Flags,D}|Is]); cg_bin_opt([{move,Src1,Dst},{bs_add,Fail,[Dst,Src2,U],Dst}|Is]) -> cg_bin_opt([{bs_add,Fail,[Src1,Src2,U],Dst}|Is]); @@ -1590,11 +1602,6 @@ cg_bin_opt([I|Is]) -> [I|cg_bin_opt(Is)]; cg_bin_opt([]) -> []. -cg_bo_newregs(R, {x,X}) when R-1 =:= X -> R-1; -cg_bo_newregs(R, _) -> R. - -%% Common for new and old binary code generation. - cg_bin_put({bin_seg,[],S0,U,T,Fs,[E0,Next]}, Fail, Bef) -> S1 = cg_reg_arg(S0, Bef), E1 = cg_reg_arg(E0, Bef), |