[LLVMdev] dragonegg pb05 for gcc 4.5.4 vs 4.6.1

[Jack Howarth]

With current dragonegg svn, the Polyhedron 2005 benchmarks
all now pass when using the compiler plugin under FSF gcc 4.6.1
on x86_64-apple-darwin11. The differences between the runtime
and compile times when using the same plugin under FSF gcc 4.5.4svn
are small. Once new vector_select feature is available in llvm and
-fplugin-arg-dragonegg-enable-gcc-optzns supports -ftree-vectorizer
we might see more of a difference between the two FSF gcc releases.

-ffast-math -funroll-loops -msse3 -O3

Runtime
Benchmark         gcc 4.5.4        gcc 4.6.1
ac                12.19            10.99
aermod            17.84            17.52
air                7.83             7.66
capacita          46.11            45.84
channel            1.96             1.96
doduc             30.17            30.43
fatigue            8.96             9.12
gas_dyn           11.75            11.50
induct            24.52            24.46
linkpk            15.73            15.64
mbdx              12.10            12.01
nf                29.08            29.27
protein           40.44            41.04
rnflow            31.89            31.90
test_fpu          11.34            11.33
tfft               2.19             2.19

mean time         13.98            13.85

Compile time
Benchmark         gcc 4.5.4        gcc 4.6.1
ac                 0.79             0.30
aermod            20.87            21.92
air                0.81             0.86
capacita           0.43             0.53
channel            0.25             0.25
doduc              1.66             1.79
fatigue            0.83             0.87
gas_dyn            0.77             0.74
induct             1.65             1.87
linkpk             0.20             0.21
mbdx               0.60             0.64
nf                 0.27             0.32
protein            0.97             1.07
rnflow             1.24             1.38
test_fpu           1.03             1.04
tfft               0.19             0.20