Hello,
Below are some compile times and sizes I measured for a bunch of GCC releases.
The test compilers are listed in the tables. All of them were compiled
with gcc 4.7.2 (i.e. not bootstrapped). Test machine is gcc110
(powerpc64) which was otherwise idle. Times are "user" times in
seconds, from /usr/bin/time. GCC 4.4 is not included because it failed
to build with default configure options (linker error, "undefined
reference to symbol 'ppl_finalize'").
Interesting observations:
* GCC 4.8.0 is not slower than, say, GCC 4.2.4 for an optimized non-debug build.
* with debug info, compilation time has increased by ~17% (but debug
info is much more accurate than before)
* cc1 for GCC 4.8.0 cc1 is 2 times the size of cc1 for GCC 4.2.4!
* cc1 for GCC 4.8.0 has a much larger .bss section than previous releases
I started looking into this because I've noticed compilations of many
small files being slower. I wonder if the larger cc1 and .bss sections
could be in part responsible for that...?
Ciao!
Steven
Test set are cc1-i files for trunk r189478, configured with release checking:
Compiler flags: -S -O2 -fpreprocessed:
Run 1 Run 2 Run 3 Avg Diff
4.2.4 368.72 368.72 368.85 369 0.0%
4.3.6 337.28 336.01 336.18 336 -8.9%
4.5.4 335.73 337.86 339.75 338 -8.4%
4.6.3 343.95 345.86 341.11 344 -6.8%
4.7.2 370.06 369.66 376.77 372 0.8%
4.8.0 374.84 373.59 374.13 374 1.4%
Compiler flags: -S -O2 -g -fpreprocessed:
Run 1 Run 2 Run 3 Avg Diff
4.2.4 391.47 390.43 393.22 392 0.0%
4.3.6 356.55 357.02 358.14 357 -8.9%
4.5.4 389.00 389.50 396.37 392 0.0%
4.6.3 418.18 420.67 426.80 422 7.7%
4.7.2 444.98 445.67 452.52 448 14.3%
4.8.0 456.81 456.96 468.29 461 17.6%
cc1 binary size:
text data bss dec hex filename
6460157 374800 535656 7370613 707775 4.2.4/cc1
7558042 666080 436744 8660866 842782 4.3.6/cc1
10917491 775144 684544 12377179 bcdc5b 4.5.4/cc1
11715323 489512 984224 13189059 c93fc3 4.6.3/cc1
12351879 484968 1193672 14030519 d616b7 4.7.2/cc1
13731087 499080 781496 15011663 e50f4f 4.8.0/cc1
Top 10 files:
4.2.4 (327 .o files):
text data bss dec hex filename
102176 1504 212 103892 195d4 combine.o
110096 7728 1429 119253 1d1d5 builtins.o
124368 2304 28 126700 1eeec fold-const.o
129724 3112 2804 135640 211d8 c-common.o
142719 6032 992 149743 248ef dwarf2out.o
173416 216 0 173632 2a640 insn-attrtab.o
195168 18144 448 213760 34300 rs6000.o
206575 14848 0 221423 360ef insn-emit.o
305932 1368 0 307300 4b064 insn-recog.o
742464 264 16 742744 b5558 insn-automata.o
7000225 459384 473148 7932757 790b55 (TOTALS)
4.3.6 (354 .o files):
text data bss dec hex filename
104936 1616 204 106756 1a104 combine.o
134040 8840 1429 144309 233b5 builtins.o
142897 2512 28 145437 2381d fold-const.o
145850 3464 2992 152306 252f2 c-common.o
153631 6424 1032 161087 2753f dwarf2out.o
215076 19232 480 234788 39524 rs6000.o
228427 16416 0 244843 3bc6b insn-emit.o
247248 240 0 247488 3c6c0 insn-attrtab.o
316300 1288 0 317588 4d894 insn-recog.o
803520 296 16 803832 c43f8 insn-automata.o
7941854 750682 348048 9040584 89f2c8 (TOTALS)
4.5.4 (393 .o files):
text data bss dec hex filename
115029 3081 160 118270 1cdfe c-decl.o
156564 9376 975 166915 28c03 builtins.o
176650 3996 3080 183726 2cdae c-common.o
196683 2720 28 199431 30b07 fold-const.o
224735 8665 1200 234600 39468 dwarf2out.o
263028 23560 3080 289668 46b84 rs6000.o
311123 22944 0 334067 518f3 insn-emit.o
383160 264 0 383424 5d9c0 insn-attrtab.o
392932 1592 0 394524 6051c insn-recog.o
1714644 320 16 1714980 1a2b24 insn-automata.o
10907556 880995 436874 12225425 ba8b91 (TOTALS)
4.6.3 (409 .o files):
text data bss dec hex filename
157700 9352 63 167115 28ccb builtins.o
164455 224 0 164679 28347 gcc-options.o
195747 328 0 196075 2fdeb options.o
198157 2432 28 200617 30fa9 fold-const.o
249087 9017 1200 259304 3f4e8 dwarf2out.o
281748 24060 3152 308960 4b6e0 rs6000.o
373251 23600 0 396851 60e33 insn-emit.o
395996 1464 0 397460 61094 insn-recog.o
641624 1624 0 643248 9d0b0 insn-attrtab.o
1729733 344 16 1730093 1a662d insn-automata.o
11917280 545628 280335 12743243 c2724b (TOTALS)
4.7.2 (436 .o files):
text data bss dec hex filename
124325 3009 152 127486 1f1fe c-decl.o
165972 11112 63 177147 2b3fb builtins.o
186159 448 0 186607 2d8ef options.o
204102 2520 28 206650 3273a fold-const.o
263384 8344 956 272684 4292c dwarf2out.o
321860 10516 3296 335672 51f38 rs6000.o
364559 23520 0 388079 5ebef insn-emit.o
368024 1296 0 369320 5a2a8 insn-recog.o
628600 1624 0 630224 99dd0 insn-attrtab.o
1730405 344 16 1730765 1a68cd insn-automata.o
12544997 547239 295406 13387642 cc477a (TOTALS)
4.8.0 (440 .o files):
text data bss dec hex filename
179600 11464 10255 201319 31267 builtins.o
210363 672 5680 216715 34e8b options.o
219562 2608 32 222202 363fa fold-const.o
277147 736 0 277883 43d7b insn-latencytab.o
309396 9660 1140 320196 4e2c4 dwarf2out.o
309845 744 0 310589 4bd3d insn-dfatab.o
354656 10820 28640 394116 60384 rs6000.o
365500 1304 0 366804 598d4 insn-recog.o
420579 23056 0 443635 6c4f3 insn-emit.o
1648133 336 16 1648485 192765 insn-automata.o
13735454 575702 831821 15142977 e71041 (TOTALS)
