if at -O0 -g your change causes the user program cannot trace (I take that
means do backtrace in gdb), I see this is not acceptable. E.g Oracle
requires being able to backtrace in any optimization level to accept any
compiler as their build compiler
Sun
On Wed, Dec 7, 2011 at 3:20 PM, Gang Yu <yugang...@gmail.com> wrote:
> On Wed, Dec 7, 2011 at 2:31 PM, Yiran Wang <yiran.w...@gmail.com> wrote:
>
>> I wonder if it easily run some optimization more than wanted. GCC is not
>> copy-propagating anything for -O0.
>>
>>
> for open64, if we disable copy-propagating, we could not get the the
> switch condition simplified. the suggest "q" phase is the much the same as
> PREOPT_DUONLY_PHASE, except that we add DCE.
>
> Regards
> Gang
>
>
>>
>>
> BTW, iirc, currently, wgen/vho is running GTABLE, which effectively
>> remove some unreachable code.
>>
>> Regards,
>> Yiran
>>
>>
>> On Tue, Dec 6, 2011 at 9:27 PM, Jian-Xin Lai <laij...@gmail.com> wrote:
>>
>>> WGEN is not supposed to be an "optimization" phase. For the given
>>> phase, VHO might be a good place to eliminate the unreachable case
>>> when lowering the switch.
>>>
>>> 2011/12/7 Yiran Wang <yiran.w...@gmail.com>:
>>> > I am not a gatekeeper, but excuse me, I wonder if why not do such
>>> kind of
>>> > stuff with WGEN.
>>> >
>>> > Regards,
>>> > Yiran
>>> >
>>> >
>>> > On Tue, Dec 6, 2011 at 6:53 PM, Gang Yu <yugang...@gmail.com> wrote:
>>> >>
>>> >> Hi,
>>> >>
>>> >> Could a gatekeeper please help review the fix for
>>> >> bug798(http://bugs.open64.net/show_bug.cgi?id=798)?
>>> >>
>>> >> This is a bug for a long time, a typical bug case below:
>>> >>
>>> >> int defined_fun()
>>> >> {
>>> >> }
>>> >>
>>> >> int main()
>>> >> {
>>> >>
>>> >> int t;
>>> >> switch(sizeof(t))
>>> >> {
>>> >> case 4:
>>> >> defined_fun();
>>> >> break;
>>> >> default:
>>> >> undefined_fun();
>>> >> }
>>> >> }
>>> >>
>>> >> opencc -O0 b.c
>>> >> /tmp/cco.c7KVi5: In function `main':
>>> >> b.c:15: undefined reference to `undefined_fun'
>>> >>
>>> >> open64 does not invoke wopt at O0, so call to undefined_fun() is not
>>> >> deleted, then the linker asserts. We may have many methods to solve
>>> this
>>> >> issue, hacking wgen to cut down the unreachable branch, adding
>>> special dce
>>> >> phase before CG expansion ..... , but the simplest way is to invoke
>>> limited
>>> >> wopt functionality at O0.
>>> >>
>>> >> This is inspired by Fred Chow and Previously Sun Chan and Suneel
>>> Jain's
>>> >> comment on bug588.
>>> >>
>>> >> >My recommendation would be to do this kind of dead code
>>> >> >elimination at -O0 in Open64. That will provide greater compatibility
>>> >> >with gcc.
>>> >> >- Suneel
>>> >>
>>> >> >can you do an experiment, please use the following options "-O0
>>> >> >-phase:p" and see if the compile will go through.
>>> >> >Thx!
>>> >> >Sun
>>> >>
>>> >> We introduce a special phase q to backend, indicating invoke preopt
>>> for
>>> >> dce only. the Suggest patch below:
>>> >>
>>> >> osprey/be/be/driver.cxx -- 207cd21..22e93a8 100644
>>> >> --- a/osprey/be/be/driver.cxx
>>> >> +++ b/osprey/be/be/driver.cxx
>>> >> @@ -441,6 +441,7 @@ load_components (INT argc, char **argv)
>>> >> INT phase_argc;
>>> >> char **phase_argv;
>>> >> +
>>> >> if (!(Run_lno || Run_wopt || Run_preopt || Run_cg ||
>>> >> Run_prompf || Run_w2c || Run_w2f
>>> >> || Run_w2fc_early || Run_ipl))
>>> >> @@ -468,6 +469,10 @@ load_components (INT argc, char **argv)
>>> >> CG_Process_Command_Line (phase_argc, phase_argv, argc, argv);
>>> >> }
>>> >> + /* run preopt for dce only also invoke preopt */
>>> >> + if (Run_preopt_dceonly)
>>> >> + Run_preopt = TRUE;
>>> >> +
>>> >> if (Run_wopt || Run_preopt || Run_lno || Run_autopar) {
>>> >> Get_Phase_Args (PHASE_WOPT, &phase_argc, &phase_argv);
>>> >> #if !defined(BUILD_FAST_BIN)
>>> >> osprey/be/be/driver_util.cxx -- e8f58f9..d5c4698 100644
>>> >> --- a/osprey/be/be/driver_util.cxx
>>> >> +++ b/osprey/be/be/driver_util.cxx
>>> >> @@ -481,6 +481,12 @@ Process_Command_Line (INT argc, char **argv)
>>> >> if (strcmp (myname, "preopt") == 0)
>>> >> Run_preopt = TRUE;
>>> >> break;
>>> >> + case 'q':
>>> >> + if (strcmp (myname, "preopt") == 0) {
>>> >> + Run_preopt = TRUE;
>>> >> + Run_preopt_dceonly = TRUE;
>>> >> + }
>>> >> + break;
>>> >> case 'c':
>>> >> if (strcmp (myname, "cg") == 0)
>>> >> Run_cg = TRUE;
>>> >> osprey/be/opt/opt_main.cxx -- 4b8957c..a7e4679 100644
>>> >> --- a/osprey/be/opt/opt_main.cxx
>>> >> +++ b/osprey/be/opt/opt_main.cxx
>>> >> @@ -731,6 +731,51 @@ private:
>>> >> WOPT_Enable_Combine_Operations = FALSE;
>>> >> WOPT_Enable_SLT = FALSE;
>>> >> OPT_Enable_WHIRL_SSA = FALSE;
>>> >> + if (Run_preopt_dceonly) {
>>> >> + WOPT_Enable_Add_Do_Loop_Info =
>>> >> + WOPT_Enable_Add_Label_Loop_Info =
>>> >> + WOPT_Enable_Aggressive_dce =
>>> >> + WOPT_Enable_Aggressive_Code_Motion =
>>> >> + WOPT_Enable_Alias_Classification =
>>> >> + WOPT_Enable_Alias_Class_Fortran_Rule =
>>> >> + WOPT_Enable_Combine_Operations =
>>> >> + WOPT_Enable_Compare_Simp =
>>> >> + WOPT_Enable_CRSIMP =
>>> >> + WOPT_Enable_DCE_Alias =
>>> >> + WOPT_Enable_Edge_Placement =
>>> >> + WOPT_Enable_Exp_PRE =
>>> >> + WOPT_Enable_Fold2const =
>>> >> + WOPT_Enable_LNO_Copy_Propagate =
>>> >> + WOPT_Enable_FSA =
>>> >> + WOPT_Enable_Goto =
>>> >> + WOPT_Enable_Input_Prop =
>>> >> + WOPT_Enable_Itself_Prop =
>>> >> + WOPT_Enable_Ivar_Common =
>>> >> + WOPT_Enable_IVE =
>>> >> + WOPT_Enable_IVR =
>>> >> + WOPT_Enable_Ldx =
>>> >> + WOPT_Enable_Load_PRE =
>>> >> + WOPT_Enable_Local_Rvi =
>>> >> + WOPT_Enable_Output_Copy =
>>> >> + WOPT_Enable_Parm =
>>> >> + WOPT_Enable_Phi_Simp =
>>> >> + WOPT_Enable_RVI =
>>> >> + WOPT_Enable_SLT =
>>> >> + WOPT_Enable_Store_PRE =
>>> >> + WOPT_Enable_SSA_PRE =
>>> >> + WOPT_Enable_Vsym_Unique =
>>> >> + OPT_Enable_WHIRL_SSA =
>>> >> + WOPT_Enable_WOVP =
>>> >> + Enable_WN_Simp = // disable WHIRL
>>> >> simplifier
>>> >> + // WOPT_Enable_Zero_Version =
>>> >> + WOPT_Enable_Tail_Recur =
>>> >> + FALSE;
>>> >> +
>>> >> + WOPT_Enable_Verify = 1;
>>> >> + WOPT_Enable_DCE = WOPT_Enable_Copy_Propagate = TRUE;
>>> >> +
>>> >> +
>>> >> + }
>>> >> break;
>>> >> } // switch
>>> >> WOPT_Enable_Ldx = Indexed_Loads_Allowed;
>>> >> osprey/common/com/config.cxx -- c972676..387f9c1 100644
>>> >> --- a/osprey/common/com/config.cxx
>>> >> +++ b/osprey/common/com/config.cxx
>>> >> @@ -621,6 +621,8 @@ static OPTION_DESC Options_PHASE[] = {
>>> >> &Run_wopt, NULL},
>>> >> { OVK_BOOL, OV_INTERNAL, FALSE, "preopt", "p", 0,
>>> 0, 0,
>>> >> &Run_preopt, NULL},
>>> >> + { OVK_BOOL, OV_INTERNAL, FALSE, "q", "", 0,
>>> 0, 0,
>>> >> + &Run_preopt_dceonly, NULL},
>>> >> { OVK_BOOL, OV_INTERNAL, FALSE, "cg", "c", 0,
>>> 0, 0,
>>> >> &Run_cg, NULL},
>>> >> { OVK_BOOL, OV_INTERNAL, FALSE, "clist", NULL, 0,
>>> 0, 0,
>>> >> @@ -998,6 +1000,7 @@ BOOL Enable_EBO_Post_Proc_Rgn = TRUE ;
>>> >> BOOL Run_lno = FALSE; /* run loop-nest optimizer */
>>> >> BOOL Run_wopt = FALSE; /* run WHIRL global optimizer */
>>> >> BOOL Run_preopt = FALSE; /* run WHIRL preopt optimizer */
>>> >> +BOOL Run_preopt_dceonly = FALSE; /* run WHIRL preopt only for
>>> dce
>>> >> */
>>> >> BOOL Run_ipl = FALSE; /* run procedure summary phase */
>>> >> BOOL Run_cg = FALSE; /* run code generator */
>>> >> BOOL Run_w2c = FALSE; /* run whirl2c */
>>> >> osprey/common/com/config.h -- 3df7f78..9bdab1d 100644
>>> >> --- a/osprey/common/com/config.h
>>> >> +++ b/osprey/common/com/config.h
>>> >> @@ -732,6 +732,7 @@ extern BOOL Run_lego; /* run
>>> >> lego-lowering */
>>> >> extern BOOL Run_lego_given; /* was run lego-lowering
>>> given/not */
>>> >> extern BOOL Run_wopt; /* run WHIRL global optimizer */
>>> >> extern BOOL Run_preopt; /* run WHIRL preopt
>>> optimizer
>>> >> */
>>> >> +extern BOOL Run_preopt_dceonly; /* run WHIRL preopt only for dce
>>> */
>>> >> extern BOOL Run_cg; /* run code generator */
>>> >> extern BOOL Run_w2c; /* run whirl2c */
>>> >> extern BOOL Run_w2f; /* run whirl2f */
>>> >> osprey/driver/special_options.c -- a65a384..abe35f5 100644
>>> >> --- a/osprey/driver/special_options.c
>>> >> +++ b/osprey/driver/special_options.c
>>> >> @@ -416,13 +416,19 @@ add_special_options (void)
>>> >> *
>>> >> * -O0/-O1 -O2 -O3
>>> >> * ===========================
>>> >> - * .B,.I,.P: cg wopt/cg
>>> >> lno/wopt/cg
>>> >> - * .N: cg wopt/cg
>>> wopt/cg
>>> >> + * .B,.I: q/cg wopt/cg
>>> >> lno/wopt/cg
>>> >> + * .P: cg wopt/cg
>>> >> lno/wopt/cg
>>> >> + * .N: q/cg wopt/cg
>>> wopt/cg
>>> >> * .O: cg cg cg
>>> >> + * q means preopt for dce only.
>>> >> */
>>> >> if (source_kind == S_O)
>>> >> warning("compiles of WOPT-generated .O files will
>>> usually
>>> >> fail due to missing state information");
>>> >> if (olevel <= 1 || source_kind == S_O)
>>> >> + if ( source_kind != S_P )
>>> >> + /* bug798 open64.net. add phase q for DCE on O0 .I
>>> .B*/
>>> >> + flag = add_string_option(O_PHASE_, "q:c");
>>> >> + else
>>> >> flag = add_string_option(O_PHASE_, "c");
>>> >> else if (olevel == 2 || source_kind == S_N)
>>> >> flag = add_string_option(O_PHASE_, "w:c");
>>> >>
>>> >> could a gatekeeper pleae help a review? thanks
>>> >>
>>> >>
>>> >> Regards
>>> >> Gang
>>> >>
>>> >>
>>> >>
>>> ------------------------------------------------------------------------------
>>> >> Cloud Services Checklist: Pricing and Packaging Optimization
>>> >> This white paper is intended to serve as a reference, checklist and
>>> point
>>> >> of
>>> >> discussion for anyone considering optimizing the pricing and packaging
>>> >> model
>>> >> of a cloud services business. Read Now!
>>> >> http://www.accelacomm.com/jaw/sfnl/114/51491232/
>>> >> _______________________________________________
>>> >> Open64-devel mailing list
>>> >> Open64-devel@lists.sourceforge.net
>>> >> https://lists.sourceforge.net/lists/listinfo/open64-devel
>>> >>
>>> >
>>> >
>>> >
>>> ------------------------------------------------------------------------------
>>> > Cloud Services Checklist: Pricing and Packaging Optimization
>>> > This white paper is intended to serve as a reference, checklist and
>>> point of
>>> > discussion for anyone considering optimizing the pricing and packaging
>>> model
>>> > of a cloud services business. Read Now!
>>> > http://www.accelacomm.com/jaw/sfnl/114/51491232/
>>> > _______________________________________________
>>> > Open64-devel mailing list
>>> > Open64-devel@lists.sourceforge.net
>>> > https://lists.sourceforge.net/lists/listinfo/open64-devel
>>> >
>>>
>>>
>>>
>>> --
>>> Regards,
>>> Lai Jian-Xin
>>>
>>
>>
>
>
> ------------------------------------------------------------------------------
> Cloud Services Checklist: Pricing and Packaging Optimization
> This white paper is intended to serve as a reference, checklist and point
> of
> discussion for anyone considering optimizing the pricing and packaging
> model
> of a cloud services business. Read Now!
> http://www.accelacomm.com/jaw/sfnl/114/51491232/
> _______________________________________________
> Open64-devel mailing list
> Open64-devel@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/open64-devel
>
>
------------------------------------------------------------------------------
Cloud Services Checklist: Pricing and Packaging Optimization
This white paper is intended to serve as a reference, checklist and point of
discussion for anyone considering optimizing the pricing and packaging model
of a cloud services business. Read Now!
http://www.accelacomm.com/jaw/sfnl/114/51491232/
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