https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63155
--- Comment #54 from Rogério de Souza Moraes <rogerio.souza at gmail dot com>
---
Hi everyone,
we continue to get performance degradation as we use a new compiler version to
build the source code 'testcase-v1.c" that is available in the attachment
above.
Could you please check if the test case that I attached reproduces the same
issue, or it is a different issue?
Below are the results that I got:
# GCC 4.4.7
-bash-4.1$ gcc -ftime-report -m32 -w -c -O3 -pedantic -fwrapv -mstackrealign
-mpreferred-stack-boundary=4 testcase-v1.c -o testcase-v1.o
Execution times (seconds)
callgraph construction: 0.02 ( 0%) usr 0.01 ( 4%) sys 0.03 ( 0%) wall
2535 kB ( 1%) ggc
callgraph optimization: 0.02 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
11 kB ( 0%) ggc
cfg cleanup : 0.05 ( 1%) usr 0.00 ( 0%) sys 0.07 ( 1%) wall
151 kB ( 0%) ggc
trivially dead code : 0.04 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
0 kB ( 0%) ggc
df reaching defs : 0.40 ( 4%) usr 0.01 ( 4%) sys 0.40 ( 4%) wall
0 kB ( 0%) ggc
df live regs : 0.33 ( 3%) usr 0.00 ( 0%) sys 0.37 ( 4%) wall
0 kB ( 0%) ggc
df live&initialized regs: 0.08 ( 1%) usr 0.00 ( 0%) sys 0.12 ( 1%) wall
0 kB ( 0%) ggc
df use-def / def-use chains: 0.17 ( 2%) usr 0.00 ( 0%) sys 0.16 ( 2%)
wall 0 kB ( 0%) ggc
df reg dead/unused notes: 0.25 ( 3%) usr 0.00 ( 0%) sys 0.22 ( 2%) wall
2519 kB ( 1%) ggc
register information : 0.13 ( 1%) usr 0.00 ( 0%) sys 0.11 ( 1%) wall
0 kB ( 0%) ggc
alias analysis : 0.06 ( 1%) usr 0.00 ( 0%) sys 0.08 ( 1%) wall
1952 kB ( 1%) ggc
register scan : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
rebuild jump labels : 0.06 ( 1%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
preprocessing : 0.02 ( 0%) usr 0.02 ( 7%) sys 0.02 ( 0%) wall
466 kB ( 0%) ggc
lexical analysis : 0.03 ( 0%) usr 0.02 ( 7%) sys 0.04 ( 0%) wall
0 kB ( 0%) ggc
parser : 0.06 ( 1%) usr 0.07 (26%) sys 0.19 ( 2%) wall
18164 kB ( 9%) ggc
inline heuristics : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
tree gimplify : 0.07 ( 1%) usr 0.00 ( 0%) sys 0.06 ( 1%) wall
19793 kB (10%) ggc
tree CFG construction : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
4445 kB ( 2%) ggc
tree CFG cleanup : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.06 ( 1%) wall
1209 kB ( 1%) ggc
tree VRP : 0.20 ( 2%) usr 0.00 ( 0%) sys 0.20 ( 2%) wall
12984 kB ( 6%) ggc
tree copy propagation : 0.10 ( 1%) usr 0.00 ( 0%) sys 0.05 ( 1%) wall
9 kB ( 0%) ggc
tree find ref. vars : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
1190 kB ( 1%) ggc
tree PTA : 0.05 ( 1%) usr 0.00 ( 0%) sys 0.06 ( 1%) wall
33 kB ( 0%) ggc
tree alias analysis : 0.04 ( 0%) usr 0.01 ( 4%) sys 0.03 ( 0%) wall
308 kB ( 0%) ggc
tree flow sensitive alias: 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
tree PHI insertion : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
1349 kB ( 1%) ggc
tree SSA rewrite : 0.05 ( 1%) usr 0.00 ( 0%) sys 0.08 ( 1%) wall
16607 kB ( 8%) ggc
tree SSA other : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
tree SSA incremental : 0.11 ( 1%) usr 0.01 ( 4%) sys 0.06 ( 1%) wall
5142 kB ( 3%) ggc
tree operand scan : 0.11 ( 1%) usr 0.03 (11%) sys 0.12 ( 1%) wall
10620 kB ( 5%) ggc
dominator optimization: 0.08 ( 1%) usr 0.00 ( 0%) sys 0.11 ( 1%) wall
2130 kB ( 1%) ggc
tree CCP : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.10 ( 1%) wall
6 kB ( 0%) ggc
tree split crit edges : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
6801 kB ( 3%) ggc
tree reassociation : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
2 kB ( 0%) ggc
tree PRE : 2.94 (31%) usr 0.02 ( 7%) sys 2.99 (30%) wall
4955 kB ( 2%) ggc
tree FRE : 0.16 ( 2%) usr 0.01 ( 4%) sys 0.17 ( 2%) wall
1933 kB ( 1%) ggc
tree code sinking : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
1 kB ( 0%) ggc
tree forward propagate: 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
tree conservative DCE : 0.04 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
tree aggressive DCE : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
tree DSE : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
228 kB ( 0%) ggc
PHI merge : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
complete unrolling : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
2 kB ( 0%) ggc
tree SSA uncprop : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
tree SSA to normal : 0.07 ( 1%) usr 0.00 ( 0%) sys 0.09 ( 1%) wall
15109 kB ( 7%) ggc
tree rename SSA copies: 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
tree switch initialization conversion: 0.01 ( 0%) usr 0.00 ( 0%) sys
0.00 ( 0%) wall 0 kB ( 0%) ggc
dominance frontiers : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
dominance computation : 0.05 ( 1%) usr 0.00 ( 0%) sys 0.04 ( 0%) wall
0 kB ( 0%) ggc
control dependences : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
expand : 0.49 ( 5%) usr 0.02 ( 7%) sys 0.50 ( 5%) wall
34138 kB (17%) ggc
jump : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
forward prop : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
1556 kB ( 1%) ggc
CSE : 0.13 ( 1%) usr 0.01 ( 4%) sys 0.16 ( 2%) wall
606 kB ( 0%) ggc
dead code elimination : 0.09 ( 1%) usr 0.00 ( 0%) sys 0.07 ( 1%) wall
0 kB ( 0%) ggc
dead store elim1 : 0.10 ( 1%) usr 0.00 ( 0%) sys 0.09 ( 1%) wall
1706 kB ( 1%) ggc
dead store elim2 : 0.12 ( 1%) usr 0.00 ( 0%) sys 0.12 ( 1%) wall
4207 kB ( 2%) ggc
CSE 2 : 0.11 ( 1%) usr 0.00 ( 0%) sys 0.08 ( 1%) wall
303 kB ( 0%) ggc
branch prediction : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
2 kB ( 0%) ggc
combiner : 0.15 ( 2%) usr 0.01 ( 4%) sys 0.14 ( 1%) wall
4423 kB ( 2%) ggc
if-conversion : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
154 kB ( 0%) ggc
regmove : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
integrated RA : 0.90 ( 9%) usr 0.00 ( 0%) sys 0.89 ( 9%) wall
1788 kB ( 1%) ggc
reload : 0.39 ( 4%) usr 0.00 ( 0%) sys 0.38 ( 4%) wall
6285 kB ( 3%) ggc
reload CSE regs : 0.20 ( 2%) usr 0.01 ( 4%) sys 0.20 ( 2%) wall
8333 kB ( 4%) ggc
load CSE after reload : 0.04 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
thread pro- & epilogue: 0.06 ( 1%) usr 0.00 ( 0%) sys 0.06 ( 1%) wall
13 kB ( 0%) ggc
peephole 2 : 0.04 ( 0%) usr 0.00 ( 0%) sys 0.04 ( 0%) wall
0 kB ( 0%) ggc
rename registers : 0.06 ( 1%) usr 0.00 ( 0%) sys 0.08 ( 1%) wall
75 kB ( 0%) ggc
scheduling 2 : 0.35 ( 4%) usr 0.01 ( 4%) sys 0.35 ( 4%) wall
0 kB ( 0%) ggc
machine dep reorg : 0.05 ( 1%) usr 0.00 ( 0%) sys 0.06 ( 1%) wall
301 kB ( 0%) ggc
reorder blocks : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.05 ( 1%) wall
3708 kB ( 2%) ggc
final : 0.11 ( 1%) usr 0.00 ( 0%) sys 0.13 ( 1%) wall
3977 kB ( 2%) ggc
TOTAL : 9.48 0.27 9.83
203289 kB
####################################################################################
#GCC 6.3.1
bash-4.1$ gcc -ftime-report -m32 -w -c -O3 -pedantic -fwrapv -mstackrealign
-mpreferred-stack-boundary=4 testcase-v1.c -o testcase-v1.o
Execution times (seconds)
phase setup : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
892 kB ( 0%) ggc
phase parsing : 0.21 ( 0%) usr 0.09 ( 3%) sys 0.32 ( 0%) wall
20284 kB ( 1%) ggc
phase opt and generate : 120.50 (100%) usr 3.43 (97%) sys 125.05 (100%)
wall 3091168 kB (99%) ggc
garbage collection : 2.50 ( 2%) usr 0.02 ( 1%) sys 2.90 ( 2%) wall
0 kB ( 0%) ggc
callgraph construction : 1.81 ( 1%) usr 0.08 ( 2%) sys 2.33 ( 2%) wall
8824 kB ( 0%) ggc
callgraph optimization : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
8 kB ( 0%) ggc
ipa dead code removal : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
ipa cp : 0.99 ( 1%) usr 0.00 ( 0%) sys 0.99 ( 1%) wall
512 kB ( 0%) ggc
ipa inlining heuristics : 0.05 ( 0%) usr 0.00 ( 0%) sys 0.05 ( 0%) wall
9 kB ( 0%) ggc
ipa profile : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
ipa pure const : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
ipa icf : 5.44 ( 5%) usr 0.00 ( 0%) sys 5.44 ( 4%) wall
26 kB ( 0%) ggc
cfg cleanup : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
18 kB ( 0%) ggc
trivially dead code : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
df scan insns : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
df multiple defs : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
df reaching defs : 0.09 ( 0%) usr 0.01 ( 0%) sys 0.10 ( 0%) wall
0 kB ( 0%) ggc
df live regs : 0.13 ( 0%) usr 0.00 ( 0%) sys 0.14 ( 0%) wall
0 kB ( 0%) ggc
df live&initialized regs: 0.03 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
df must-initialized regs: 0.01 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
df use-def / def-use chains: 0.04 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%)
wall 0 kB ( 0%) ggc
df reg dead/unused notes: 0.12 ( 0%) usr 0.00 ( 0%) sys 0.12 ( 0%) wall
665 kB ( 0%) ggc
register information : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
0 kB ( 0%) ggc
alias analysis : 0.07 ( 0%) usr 0.00 ( 0%) sys 0.05 ( 0%) wall
1090 kB ( 0%) ggc
alias stmt walking : 0.08 ( 0%) usr 0.00 ( 0%) sys 0.13 ( 0%) wall
1 kB ( 0%) ggc
rebuild jump labels : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
0 kB ( 0%) ggc
preprocessing : 0.03 ( 0%) usr 0.01 ( 0%) sys 0.01 ( 0%) wall
3645 kB ( 0%) ggc
lexical analysis : 0.07 ( 0%) usr 0.03 ( 1%) sys 0.09 ( 0%) wall
0 kB ( 0%) ggc
parser (global) : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
643 kB ( 0%) ggc
parser function body : 0.11 ( 0%) usr 0.04 ( 1%) sys 0.19 ( 0%) wall
15822 kB ( 1%) ggc
parser inl. func. body : 0.00 ( 0%) usr 0.01 ( 0%) sys 0.01 ( 0%) wall
110 kB ( 0%) ggc
inline parameters : 0.13 ( 0%) usr 0.02 ( 1%) sys 0.09 ( 0%) wall
1530 kB ( 0%) ggc
tree gimplify : 0.06 ( 0%) usr 0.02 ( 1%) sys 0.06 ( 0%) wall
12544 kB ( 0%) ggc
tree eh : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
tree CFG construction : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.04 ( 0%) wall
10956 kB ( 0%) ggc
tree CFG cleanup : 0.45 ( 0%) usr 0.01 ( 0%) sys 0.46 ( 0%) wall
0 kB ( 0%) ggc
tree VRP : 25.14 (21%) usr 0.56 (16%) sys 25.73 (21%) wall
115035 kB ( 4%) ggc
tree copy propagation : 0.57 ( 0%) usr 0.00 ( 0%) sys 0.57 ( 0%) wall
0 kB ( 0%) ggc
tree PTA : 18.90 (16%) usr 0.63 (18%) sys 19.58 (16%) wall
488 kB ( 0%) ggc
tree PHI insertion : 3.90 ( 3%) usr 1.67 (47%) sys 5.58 ( 4%) wall
2912441 kB (94%) ggc
tree SSA rewrite : 12.59 (10%) usr 0.01 ( 0%) sys 12.62 (10%) wall
4709 kB ( 0%) ggc
tree SSA other : 0.09 ( 0%) usr 0.00 ( 0%) sys 0.06 ( 0%) wall
0 kB ( 0%) ggc
tree SSA incremental : 0.09 ( 0%) usr 0.00 ( 0%) sys 0.10 ( 0%) wall
94 kB ( 0%) ggc
tree operand scan : 0.04 ( 0%) usr 0.01 ( 0%) sys 0.01 ( 0%) wall
3523 kB ( 0%) ggc
dominator optimization : 1.49 ( 1%) usr 0.00 ( 0%) sys 1.50 ( 1%) wall
378 kB ( 0%) ggc
isolate eroneous paths : 0.10 ( 0%) usr 0.00 ( 0%) sys 0.10 ( 0%) wall
0 kB ( 0%) ggc
tree CCP : 9.87 ( 8%) usr 0.03 ( 1%) sys 9.94 ( 8%) wall
12 kB ( 0%) ggc
tree PHI const/copy prop: 0.26 ( 0%) usr 0.00 ( 0%) sys 0.27 ( 0%) wall
0 kB ( 0%) ggc
tree split crit edges : 0.47 ( 0%) usr 0.00 ( 0%) sys 0.48 ( 0%) wall
568 kB ( 0%) ggc
tree reassociation : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
tree PRE : 0.21 ( 0%) usr 0.00 ( 0%) sys 0.21 ( 0%) wall
6 kB ( 0%) ggc
tree FRE : 1.47 ( 1%) usr 0.00 ( 0%) sys 1.48 ( 1%) wall
6 kB ( 0%) ggc
tree backward propagate : 11.39 ( 9%) usr 0.00 ( 0%) sys 11.40 ( 9%) wall
0 kB ( 0%) ggc
tree forward propagate : 0.04 ( 0%) usr 0.00 ( 0%) sys 0.04 ( 0%) wall
0 kB ( 0%) ggc
tree phiprop : 0.11 ( 0%) usr 0.00 ( 0%) sys 0.10 ( 0%) wall
0 kB ( 0%) ggc
tree conservative DCE : 0.78 ( 1%) usr 0.01 ( 0%) sys 0.80 ( 1%) wall
0 kB ( 0%) ggc
tree aggressive DCE : 2.56 ( 2%) usr 0.00 ( 0%) sys 2.53 ( 2%) wall
12 kB ( 0%) ggc
tree DSE : 0.67 ( 1%) usr 0.00 ( 0%) sys 0.68 ( 1%) wall
0 kB ( 0%) ggc
PHI merge : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
tree slp vectorization : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
283 kB ( 0%) ggc
tree SSA uncprop : 0.83 ( 1%) usr 0.02 ( 1%) sys 0.85 ( 1%) wall
0 kB ( 0%) ggc
tree strlen optimization: 0.13 ( 0%) usr 0.00 ( 0%) sys 0.13 ( 0%) wall
0 kB ( 0%) ggc
dominance computation : 0.05 ( 0%) usr 0.01 ( 0%) sys 0.06 ( 0%) wall
0 kB ( 0%) ggc
out of ssa : 10.30 ( 9%) usr 0.24 ( 7%) sys 10.60 ( 8%) wall
47 kB ( 0%) ggc
expand vars : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
428 kB ( 0%) ggc
expand : 0.22 ( 0%) usr 0.02 ( 1%) sys 0.26 ( 0%) wall
5452 kB ( 0%) ggc
lower subreg : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
forward prop : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
246 kB ( 0%) ggc
CSE : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.04 ( 0%) wall
145 kB ( 0%) ggc
dead code elimination : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
0 kB ( 0%) ggc
dead store elim1 : 0.03 ( 0%) usr 0.01 ( 0%) sys 0.03 ( 0%) wall
720 kB ( 0%) ggc
dead store elim2 : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.05 ( 0%) wall
1042 kB ( 0%) ggc
loop init : 0.04 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
17 kB ( 0%) ggc
CSE 2 : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
56 kB ( 0%) ggc
branch prediction : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
0 kB ( 0%) ggc
combiner : 0.05 ( 0%) usr 0.00 ( 0%) sys 0.05 ( 0%) wall
965 kB ( 0%) ggc
integrated RA : 0.15 ( 0%) usr 0.00 ( 0%) sys 0.17 ( 0%) wall
2130 kB ( 0%) ggc
LRA non-specific : 0.08 ( 0%) usr 0.00 ( 0%) sys 0.06 ( 0%) wall
746 kB ( 0%) ggc
LRA virtuals elimination: 0.00 ( 0%) usr 0.00 ( 0%) sys 0.02 ( 0%) wall
461 kB ( 0%) ggc
LRA reload inheritance : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
132 kB ( 0%) ggc
LRA create live ranges : 0.12 ( 0%) usr 0.00 ( 0%) sys 0.12 ( 0%) wall
87 kB ( 0%) ggc
LRA hard reg assignment : 0.01 ( 0%) usr 0.01 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
LRA rematerialization : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
reload CSE regs : 0.07 ( 0%) usr 0.00 ( 0%) sys 0.06 ( 0%) wall
1865 kB ( 0%) ggc
load CSE after reload : 0.12 ( 0%) usr 0.00 ( 0%) sys 0.12 ( 0%) wall
138 kB ( 0%) ggc
ree : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
0 kB ( 0%) ggc
thread pro- & epilogue : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
4 kB ( 0%) ggc
if-conversion 2 : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
combine stack adjustments: 0.01 ( 0%) usr 0.00 ( 0%) sys 0.00 ( 0%) wall
37 kB ( 0%) ggc
peephole 2 : 0.02 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
348 kB ( 0%) ggc
hard reg cprop : 0.00 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
scheduling 2 : 0.11 ( 0%) usr 0.00 ( 0%) sys 0.13 ( 0%) wall
320 kB ( 0%) ggc
reorder blocks : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
528 kB ( 0%) ggc
shorten branches : 0.01 ( 0%) usr 0.00 ( 0%) sys 0.01 ( 0%) wall
0 kB ( 0%) ggc
final : 0.03 ( 0%) usr 0.00 ( 0%) sys 0.03 ( 0%) wall
1302 kB ( 0%) ggc
straight-line strength reduction: 0.14 ( 0%) usr 0.01 ( 0%) sys 0.15 (
0%) wall 0 kB ( 0%) ggc
rest of compilation : 0.12 ( 0%) usr 0.01 ( 0%) sys 0.16 ( 0%) wall
33 kB ( 0%) ggc
remove unused locals : 3.42 ( 3%) usr 0.01 ( 0%) sys 3.46 ( 3%) wall
0 kB ( 0%) ggc
address taken : 1.19 ( 1%) usr 0.01 ( 0%) sys 1.21 ( 1%) wall
0 kB ( 0%) ggc
unaccounted todo : 0.08 ( 0%) usr 0.00 ( 0%) sys 0.09 ( 0%) wall
40 kB ( 0%) ggc
TOTAL : 120.71 3.52 125.38
3112354 kB
####################################################################################
# GCC 8.3.1
bash-4.1$ gcc -ftime-report -m32 -w -c -O3 -pedantic -fwrapv -mstackrealign
-mpreferred-stack-boundary=4 testcase-v1.c -o testcase-v1.o
Time variable usr sys wall
GGC
phase setup : 0.00 ( 0%) 0.01 ( 0%) 0.01 ( 0%)
1047 kB ( 0%)
phase parsing : 0.21 ( 0%) 0.08 ( 0%) 0.32 ( 0%)
20551 kB ( 0%)
phase opt and generate : 189.32 (100%) 24.44 (100%) 367.57 (100%)
5277730 kB (100%)
garbage collection : 7.52 ( 4%) 2.16 ( 9%) 32.80 ( 9%)
0 kB ( 0%)
dump files : 0.00 ( 0%) 0.01 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
callgraph construction : 4.62 ( 2%) 4.29 ( 17%) 59.37 ( 16%)
9442 kB ( 0%)
callgraph optimization : 0.28 ( 0%) 0.04 ( 0%) 0.60 ( 0%)
0 kB ( 0%)
ipa function summary : 0.13 ( 0%) 0.22 ( 1%) 2.63 ( 1%)
11 kB ( 0%)
ipa dead code removal : 0.00 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
ipa cp : 2.11 ( 1%) 2.48 ( 10%) 30.08 ( 8%)
2 kB ( 0%)
ipa inlining heuristics : 0.00 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
ipa pure const : 0.02 ( 0%) 0.01 ( 0%) 0.05 ( 0%)
0 kB ( 0%)
ipa icf : 12.01 ( 6%) 4.13 ( 17%) 60.34 ( 16%)
29 kB ( 0%)
ipa free inline summary : 0.00 ( 0%) 0.01 ( 0%) 0.07 ( 0%)
0 kB ( 0%)
cfg cleanup : 0.00 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
18 kB ( 0%)
trivially dead code : 0.01 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
df scan insns : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
df multiple defs : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
df reaching defs : 0.08 ( 0%) 0.00 ( 0%) 0.08 ( 0%)
0 kB ( 0%)
df live regs : 0.11 ( 0%) 0.00 ( 0%) 0.12 ( 0%)
0 kB ( 0%)
df live&initialized regs : 0.02 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
0 kB ( 0%)
df must-initialized regs : 0.02 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
df use-def / def-use chains : 0.05 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
0 kB ( 0%)
df reg dead/unused notes : 0.11 ( 0%) 0.00 ( 0%) 0.12 ( 0%)
684 kB ( 0%)
register information : 0.03 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
0 kB ( 0%)
alias analysis : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
1090 kB ( 0%)
alias stmt walking : 0.13 ( 0%) 0.02 ( 0%) 0.36 ( 0%)
1 kB ( 0%)
register scan : 0.02 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
140 kB ( 0%)
rebuild jump labels : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
preprocessing : 0.04 ( 0%) 0.01 ( 0%) 0.11 ( 0%)
3722 kB ( 0%)
lexical analysis : 0.04 ( 0%) 0.02 ( 0%) 0.09 ( 0%)
0 kB ( 0%)
parser (global) : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
716 kB ( 0%)
parser struct body : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
61 kB ( 0%)
parser function body : 0.13 ( 0%) 0.05 ( 0%) 0.10 ( 0%)
15942 kB ( 0%)
early inlining heuristics : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
inline parameters : 0.16 ( 0%) 0.19 ( 1%) 0.47 ( 0%)
1538 kB ( 0%)
tree gimplify : 0.06 ( 0%) 0.01 ( 0%) 0.07 ( 0%)
14496 kB ( 0%)
tree eh : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
0 kB ( 0%)
tree CFG construction : 0.04 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
11884 kB ( 0%)
tree CFG cleanup : 0.64 ( 0%) 0.00 ( 0%) 0.65 ( 0%)
0 kB ( 0%)
tree tail merge : 1.50 ( 1%) 0.00 ( 0%) 1.50 ( 0%)
0 kB ( 0%)
tree VRP : 9.73 ( 5%) 2.02 ( 8%) 12.15 ( 3%)
165762 kB ( 3%)
tree Early VRP : 13.07 ( 7%) 0.23 ( 1%) 13.32 ( 4%)
496545 kB ( 9%)
tree copy propagation : 0.88 ( 0%) 0.00 ( 0%) 0.89 ( 0%)
0 kB ( 0%)
tree PTA : 28.88 ( 15%) 4.22 ( 17%) 38.06 ( 10%)
46436 kB ( 1%)
tree PHI insertion : 5.78 ( 3%) 1.96 ( 8%) 7.83 ( 2%)
4254415 kB ( 80%)
tree SSA rewrite : 15.12 ( 8%) 0.02 ( 0%) 15.13 ( 4%)
3780 kB ( 0%)
tree SSA other : 0.21 ( 0%) 0.16 ( 1%) 0.34 ( 0%)
0 kB ( 0%)
tree SSA incremental : 0.14 ( 0%) 0.00 ( 0%) 0.16 ( 0%)
94 kB ( 0%)
tree operand scan : 0.03 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
3619 kB ( 0%)
dominator optimization : 5.51 ( 3%) 0.10 ( 0%) 5.66 ( 2%)
165892 kB ( 3%)
backwards jump threading : 0.01 ( 0%) 0.01 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
isolate eroneous paths : 0.10 ( 0%) 0.00 ( 0%) 0.09 ( 0%)
0 kB ( 0%)
tree CCP : 14.39 ( 8%) 1.75 ( 7%) 16.89 ( 5%)
75 kB ( 0%)
tree PHI const/copy prop : 0.43 ( 0%) 0.00 ( 0%) 0.43 ( 0%)
0 kB ( 0%)
tree split crit edges : 0.40 ( 0%) 0.01 ( 0%) 0.44 ( 0%)
274 kB ( 0%)
tree reassociation : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
0 kB ( 0%)
tree PRE : 3.41 ( 2%) 0.14 ( 1%) 3.55 ( 1%)
281 kB ( 0%)
tree FRE : 20.53 ( 11%) 0.04 ( 0%) 20.61 ( 6%)
5 kB ( 0%)
tree linearize phis : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
6 kB ( 0%)
tree backward propagate : 1.41 ( 1%) 0.04 ( 0%) 1.92 ( 1%)
0 kB ( 0%)
tree forward propagate : 3.69 ( 2%) 0.00 ( 0%) 3.70 ( 1%)
0 kB ( 0%)
tree phiprop : 0.10 ( 0%) 0.00 ( 0%) 0.09 ( 0%)
0 kB ( 0%)
tree conservative DCE : 1.63 ( 1%) 0.00 ( 0%) 1.66 ( 0%)
0 kB ( 0%)
tree aggressive DCE : 3.75 ( 2%) 0.01 ( 0%) 3.77 ( 1%)
12 kB ( 0%)
tree DSE : 1.09 ( 1%) 0.00 ( 0%) 1.07 ( 0%)
0 kB ( 0%)
PHI merge : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
tree slp vectorization : 0.02 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
747 kB ( 0%)
tree SSA uncprop : 1.44 ( 1%) 0.00 ( 0%) 1.44 ( 0%)
0 kB ( 0%)
gimple widening/fma detection : 0.13 ( 0%) 0.00 ( 0%) 0.13 ( 0%)
0 kB ( 0%)
tree strlen optimization : 0.19 ( 0%) 0.00 ( 0%) 0.19 ( 0%)
0 kB ( 0%)
dominance computation : 0.03 ( 0%) 0.01 ( 0%) 0.13 ( 0%)
0 kB ( 0%)
control dependences : 0.02 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
0 kB ( 0%)
out of ssa : 17.90 ( 9%) 0.06 ( 0%) 17.97 ( 5%)
47 kB ( 0%)
expand vars : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
444 kB ( 0%)
expand : 0.32 ( 0%) 0.01 ( 0%) 0.33 ( 0%)
5520 kB ( 0%)
forward prop : 0.03 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
246 kB ( 0%)
CSE : 0.02 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
145 kB ( 0%)
dead code elimination : 0.02 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
0 kB ( 0%)
dead store elim1 : 0.03 ( 0%) 0.00 ( 0%) 0.03 ( 0%)
720 kB ( 0%)
dead store elim2 : 0.03 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
1070 kB ( 0%)
loop init : 0.01 ( 0%) 0.00 ( 0%) 0.04 ( 0%)
22 kB ( 0%)
CSE 2 : 0.02 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
56 kB ( 0%)
branch prediction : 0.05 ( 0%) 0.01 ( 0%) 0.05 ( 0%)
0 kB ( 0%)
combiner : 0.07 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
965 kB ( 0%)
integrated RA : 0.12 ( 0%) 0.00 ( 0%) 0.24 ( 0%)
2193 kB ( 0%)
LRA non-specific : 0.07 ( 0%) 0.00 ( 0%) 0.07 ( 0%)
818 kB ( 0%)
LRA virtuals elimination : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
460 kB ( 0%)
LRA reload inheritance : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
132 kB ( 0%)
LRA create live ranges : 0.18 ( 0%) 0.00 ( 0%) 0.18 ( 0%)
87 kB ( 0%)
LRA hard reg assignment : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
LRA rematerialization : 0.00 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
reload CSE regs : 0.06 ( 0%) 0.00 ( 0%) 0.06 ( 0%)
1865 kB ( 0%)
load CSE after reload : 0.11 ( 0%) 0.00 ( 0%) 0.11 ( 0%)
138 kB ( 0%)
ree : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
thread pro- & epilogue : 0.02 ( 0%) 0.01 ( 0%) 0.03 ( 0%)
6 kB ( 0%)
combine stack adjustments : 0.01 ( 0%) 0.00 ( 0%) 0.00 ( 0%)
37 kB ( 0%)
peephole 2 : 0.01 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
348 kB ( 0%)
hard reg cprop : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
scheduling 2 : 0.13 ( 0%) 0.00 ( 0%) 0.13 ( 0%)
377 kB ( 0%)
reorder blocks : 0.02 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
518 kB ( 0%)
shorten branches : 0.01 ( 0%) 0.00 ( 0%) 0.01 ( 0%)
0 kB ( 0%)
final : 0.03 ( 0%) 0.00 ( 0%) 0.09 ( 0%)
1302 kB ( 0%)
straight-line strength reduction : 0.24 ( 0%) 0.00 ( 0%) 0.24 ( 0%)
0 kB ( 0%)
initialize rtl : 0.00 ( 0%) 0.00 ( 0%) 0.02 ( 0%)
9 kB ( 0%)
rest of compilation : 1.18 ( 1%) 0.06 ( 0%) 1.28 ( 0%)
82789 kB ( 2%)
remove unused locals : 4.82 ( 3%) 0.00 ( 0%) 5.02 ( 1%)
0 kB ( 0%)
address taken : 1.88 ( 1%) 0.00 ( 0%) 1.91 ( 1%)
0 kB ( 0%)
TOTAL : 189.53 24.53 367.91
5299338 kB
####################################################################################
As you can see, in each newer GCC version the performance is even more
degraded.
F.Y.I I also tried the same code using LLVM v8.0.0 which complied similar to
GCC 4.4.7.
Best regards,
--
Rogerio
