HPC Magazine February 2014 - An Introduction to Performance Programming - part I.

Listing 7: Same compilation as in Listing 5 using the #pragma ivdep directive on external loops.

HydroC/oaccHydroC_2DMPI/Src$ icc -std=c99 -O3 -vec-report2 -Wno-unknown-pragmas -S
riemann.c
riemann.c(51): (col. 3) remark: LOOP WAS VECTORIZED.
riemann.c(109): (col. 11) remark: LOOP WAS VECTORIZED.
riemann.c(103): (col. 7) remark: loop was not vectorized: not inner loop.
riemann.c(300): (col. 11) remark: loop was not vectorized: existence of vector dependence.
riemann.c(298): (col. 9) remark: loop was not vectorized: not inner loop.
riemann.c(293): (col. 7) remark: loop was not vectorized: not inner loop.