regarding optimization options in phase ordering

[pms <pmshiva at gmail dot com>]

Hi,
     We've a problem here. we were trying to use cc1 with & without -O
option to verify the optimizations happening in our sample code. these r the
list of outputs after each compilation
without -O
pms@Shiva:~/Desktop/Compilers/GCC/build/test$ ls
1.c                1.c.011t.ehopt        1.c.038t.release_ssa
1.c.001t.tu        1.c.012t.eh           1.c.123t.optimized
1.c.003t.original  1.c.013t.cfg          1.c.125t.blocks
1.c.004t.gimple    1.c.014t.cplxlower0   1.c.126t.final_cleanup
1.c.006t.vcg       1.c.015t.veclower     1.c.203t.statistics
1.c.007t.useless   1.c.021t.cleanup_cfg  1.s
1.c.010t.lower     1.c.023t.ssa          a.out

with -O

1.c                           1.c.051t.ccp2         1.c.085t.sink
1.c.001t.tu                   1.c.052t.forwprop2    1.c.086t.loop
1.c.003t.original             1.c.054t.alias        1.c.087t.loopinit
1.c.004t.gimple               1.c.055t.retslot      1.c.088t.copyprop4
1.c.006t.vcg                  1.c.056t.phiprop      1.c.089t.dceloop1
1.c.007t.useless              1.c.057t.fre          1.c.090t.lim
1.c.010t.lower                1.c.058t.copyprop2    1.c.093t.sccp
1.c.011t.ehopt                1.c.059t.mergephi2    1.c.094t.empty
1.c.012t.eh                   1.c.061t.dce1         1.c.099t.ivcanon
1.c.013t.cfg                  1.c.062t.cselim       1.c.104t.cunroll
1.c.015t.veclower             1.c.063t.ifcombine    1.c.107t.ivopts
1.c.021t.cleanup_cfg          1.c.064t.phiopt1      1.c.108t.loopdone
1.c.023t.ssa                  1.c.066t.ch           1.c.111t.reassoc2
1.c.024t.early_optimizations  1.c.068t.cplxlower    1.c.113t.dom2
1.c.025t.einline2             1.c.069t.sra          1.c.114t.phicprop2
1.c.026t.copyrename1          1.c.070t.copyrename3  1.c.115t.cddce2
1.c.027t.ccp1                 1.c.071t.dom1         1.c.117t.dse2
1.c.028t.forwprop1            1.c.072t.phicprop1    1.c.118t.forwprop4
1.c.029t.addressables1        1.c.073t.dse1         1.c.119t.phiopt3
1.c.030t.esra                 1.c.074t.reassoc1     1.c.121t.copyrename4
1.c.031t.copyprop1            1.c.075t.dce2         1.c.122t.uncprop
1.c.032t.mergephi1            1.c.076t.forwprop3    1.c.123t.optimized
1.c.033t.cddce1               1.c.077t.phiopt2      1.c.124t.nrv
1.c.034t.sdse                 1.c.078t.objsz        1.c.125t.blocks
1.c.036t.switchconv           1.c.079t.ccp3         1.c.126t.final_cleanup
1.c.037t.profile              1.c.080t.copyprop3    1.c.203t.statistics
1.c.038t.release_ssa          1.c.081t.fab          1.s
1.c.048t.addressables2        1.c.082t.sincos       a.out
1.c.049t.copyrename2          1.c.083t.crited

But here, we tried to see the differences, until 1.c.027t.ccp1, the output
for the following source 1.c
#include
int main()

{
        int a=5;
        int b;
        b=a;
        printf("the number is :%d",b);
}

was 1.c.026t.copyrename1
;; Function main (main)

main ()
{
  int b;
  int a;

:
  a_2 = b_1(D);
  return;

}
but in 1.c.027t.ccp1, the output doesnot contain the actual assignment b=a.
;; Function main (main)

main ()
{
  int b;
  int a;

:
  return;

}

We want to know, without b=a, how is it generating the final code for b=a

Kindly help

-- 
View this message in context: http://www.nabble.com/regarding-optimization-options-in-phase-ordering-tp24863416p24863416.html
Sent from the gcc - Dev mailing list archive at Nabble.com.