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[ 4 / 4 ] Application profile is long enough (199.72 s)
To have good quality measurements, it is advised that the application profiling time is greater than 10 seconds.
[ 0 / 3 ] Optimization level option not used
To have better performances, it is advised to help the compiler by using a proper optimization level (-O2 of higher). Warning, depending on compilers, faster optimization levels can decrease numeric accuracy.
[ 0 / 3 ] Helper debug compilation options -g and -fno-omit-frame-pointer are missing
-g option gives access to debugging informations, such are source locations and -fno-omit-frame-pointer improve the accuracy of callchains found during the application profiling.
[ 0 / 3 ] Architecture specific options are not used
Architecture specific options are needed to produce efficient code for a specific processor ( -x(target) or -ax(target) ).
[ 2 / 2 ] Application is correctly profiled ("Others" category represents 0 % of the execution time)
To have a representative profiling, it is advised that the category "Others" represents less than 20% of the execution time in order to analyze as much as possible of the user code
[ 4 / 4 ] Enough time of the experiment time spent in analyzed loops (31.99%)
If the time spent in analyzed loops is less than 30%, standard loop optimizations will have a limited impact on application performances.
[ 4 / 4 ] Loop profile is not flat
At least one loop coverage is greater than 4% (8.60%), representing an hotspot for the application
[ 4 / 4 ] Enough time of the experiment time spent in analyzed innermost loops (22.90%)
If the time spent in analyzed innermost loops is less than 15%, standard innermost loop optimizations such as vectorisation will have a limited impact on application performances.
[ 3 / 3 ] Less than 10% (0%) is spend in BLAS1 operations
It could be more efficient to inline by hand BLAS1 operations
[ 3 / 3 ] Cumulative Outermost/In between loops coverage (9.09%) lower than cumulative innermost loop coverage (22.9%)
Having cumulative Outermost/In between loops coverage greater than cumulative innermost loop coverage will make loop optimization more complex
[ 2 / 2 ] Less than 10% (0%) is spend in Libm/SVML (special functions)
[ 2 / 2 ] Less than 10% (0%) is spend in BLAS2 operations
BLAS2 calls usually could make a poor cache usage and could benefit from inlining.
Loop ID | Module | Analysis | Penalty Score | Coverage (%) | Vectorization Ratio (%) | Vector Length Use (%) |
---|---|---|---|---|---|---|
►1732 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 74 | 8.6 | 95.59 | 90.81 |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 24 issues (= calls) costing 1 point each. | 24 | ||||
○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 11 issues ( = arrays) costing 2 points each | 22 | ||||
○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 9 issues ( = data accesses) costing 2 point each. | 18 | ||||
○ | [SA] Less than 10% of the FP ADD/SUB/MUL arithmetic operations are performed using FMA - Reorganize arithmetic expressions to exhibit potential for FMA. This issue costs 4 points. | 4 | ||||
○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
○ | [SA] Presence of a large number of scalar integer instructions - Simplify loop structure, perform loop splitting or perform unroll and jam. This issue costs 2 points. | 2 | ||||
○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
►1730 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 73 | 3.54 | 95.71 | 91.07 |
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 23 issues (= calls) costing 1 point each. | 23 | ||||
○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 11 issues ( = arrays) costing 2 points each | 22 | ||||
○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 9 issues ( = data accesses) costing 2 point each. | 18 | ||||
○ | [SA] Less than 10% of the FP ADD/SUB/MUL arithmetic operations are performed using FMA - Reorganize arithmetic expressions to exhibit potential for FMA. This issue costs 4 points. | 4 | ||||
○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
○ | [SA] Presence of a large number of scalar integer instructions - Simplify loop structure, perform loop splitting or perform unroll and jam. This issue costs 2 points. | 2 | ||||
○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
►26516 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 101 | 2.66 | 60.87 | 36.96 |
○ | [SA] Too many paths (95 paths) - Simplify control structure. There are 95 issues ( = paths) costing 1 point each with a malus of 4 points. | 99 | ||||
○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 | ||||
►1760 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 108 | 2.2 | 90.32 | 82.53 |
○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 19 issues ( = arrays) costing 2 points each | 38 | ||||
○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 15 issues ( = data accesses) costing 2 point each. | 30 | ||||
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 28 issues (= calls) costing 1 point each. | 28 | ||||
○ | [SA] Less than 10% of the FP ADD/SUB/MUL arithmetic operations are performed using FMA - Reorganize arithmetic expressions to exhibit potential for FMA. This issue costs 4 points. | 4 | ||||
○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
○ | [SA] Non innermost loop (InBetween) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
○ | [SA] Presence of a large number of scalar integer instructions - Simplify loop structure, perform loop splitting or perform unroll and jam. This issue costs 2 points. | 2 | ||||
○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
►26128 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 200 | 0.84 | 33.33 | 27.47 |
○ | [SA] Too many paths (194 paths) - Simplify control structure. There are 194 issues ( = paths) costing 1 point each with a malus of 4 points. | 198 | ||||
○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 | ||||
►26504 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 1002 | 0.81 | 26.62 | 22.32 |
○ | [SA] Too many paths (4057 paths) - Simplify control structure. There are 4057 issues ( = paths) costing 1 point, limited to 1000. | 1000 | ||||
○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 | ||||
►4144 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 20 | 0.75 | 93.18 | 94.03 |
○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 4 issues ( = arrays) costing 2 points each | 8 | ||||
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 1 issues ( = indirect data accesses) costing 4 point each. | 4 | ||||
○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 2 issues ( = data accesses) costing 2 point each. | 4 | ||||
○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
○ | [SA] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 | ||||
○ | [DA] The ratio FP/LS (floating point / memory accesses) is smaller than 0.8 (0.56) - Focus on optimizing data accesses. | 0 | ||||
►26127 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 31 | 0.75 | 88.89 | 79.17 |
○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 6 issues ( = arrays) costing 2 points each | 12 | ||||
○ | [SA] Presence of constant non unit stride data access - Use array restructuring, perform loop interchange or use gather instructions to lower a bit the cost. There are 4 issues ( = data accesses) costing 2 point each. | 8 | ||||
○ | [DA] Low iteration count (4 < 10) - Perform full unroll. Use compiler pragmas. Use PGO/FDO compiler options. Force compiler to use masked instructions. This issue costs 5 points. | 5 | ||||
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BROADCAST) - Simplify data access and try to get stride 1 access. There are 4 issues (= instructions) costing 1 point each. | 4 | ||||
○ | [SA] Inefficient vectorization: use of shorter than available vector length - Force compiler to use proper vector length. CAUTION: use of 512 bits vectors could be more expensive than 256 bits on some processors. Use intrinsics (costly and not portable). The issue costs 2 points. | 2 | ||||
○ | Warning! There is no dynamic data for this loop. Some checks can not been performed. | 0 | ||||
►1727 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 104 | 0.68 | 45.38 | 42.12 |
○ | [SA] Too many paths (90 paths) - Simplify control structure. There are 90 issues ( = paths) costing 1 point each with a malus of 4 points. | 94 | ||||
○ | [SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 8 issues (= calls) costing 1 point each. | 8 | ||||
○ | [SA] Non innermost loop (Outermost) - Collapse loop with innermost ones. This issue costs 2 points. | 2 | ||||
○ | Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option. | 0 | ||||
►23153 | libgromacs.so.8 | Partial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access. | 4 | 0.66 | 0 | 12.5 |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 1 issues ( = indirect data accesses) costing 4 point each. | 4 |