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exec - 2023-09-05 11:53:40 - MAQAO 2.17.8

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Stylizer  

[ 0 / 4 ] Application profile is too short (0.68 s)

If the overall application profiling time is less than 10 seconds, many of the measurements at function or loop level will very likely be under the measurement quality threshold (0,1 seconds). Rerun to increase runtime duration: for example use a larger dataset or include a repetition loop.

[ 3 / 3 ] Optimization level option -O2 is used

To have better performances, it is advised to help the compiler by using a proper optimization level (-O2)

[ 3 / 3 ] Helper debug compilation options -g and -fno-omit-frame-pointer are used

-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.

[ 3 / 3 ] Architecture specific option -x SKYLAKE is used

[ 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

Optimizer

Loop IDModuleAnalysisPenalty ScoreCoverage (%)Vectorization
Ratio (%)
Vector Length
Use (%)
672execInefficient vectorization.833.09100100
[DA] Ratio time (ORIG)/time (DL1) is greater than 3 (7.45) - Perform blocking. Perform array restructuring. There are 0 issues (= non unit stride or indirect memory access) costing 2 point each, with an additional malus of 8 points due to the ORIG/DL1 ratio.8
679execInefficient vectorization.3423.53100100
[SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 12 issues ( = arrays) costing 2 points each24
[DA] Ratio time (ORIG)/time (DL1) is greater than 3 (5.10) - Perform blocking. Perform array restructuring. There are 1 issues (= non unit stride or indirect memory access) costing 2 point each, with an additional malus of 6 points due to the ORIG/DL1 ratio.8
[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
971execPartial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access.8411.0390.9189.22
[SA] Presence of expensive FP instructions - Perform hoisting, change algorithm, use SVML or proper numerical library or perform value profiling (count the number of distinct input values). There are 8 issues (= instructions) costing 4 points each.32
[SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 10 issues ( = arrays) costing 2 points each20
[SA] Presence of expensive instructions (GATHER/SCATTER) - Use array restructuring. There are 3 issues (= instructions) costing 4 points each.12
[SA] Presence of special instructions executing on a single port (BLEND/MERGE, BROADCAST) - Simplify data access and try to get stride 1 access. There are 10 issues (= instructions) costing 1 point each.10
[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] 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] Inefficient vectorization: use of masked instructions - Simplify control structure. 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
654execInefficient vectorization.113422.94100100
[DA] Ratio time (ORIG)/time (DL1) is greater than 3 (11337.47) - Perform blocking. Perform array restructuring. There are 0 issues (= non unit stride or indirect memory access) costing 2 point each, with an additional malus of 11338 points due to the ORIG/DL1 ratio.11338
[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
230execPartial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access.212.2192.6871.67
[SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, COMPRESS/EXPAND, BLEND/MERGE, SHUFFLE/PERM, BROADCAST) - Simplify data access and try to get stride 1 access. There are 7 issues (= instructions) costing 1 point each.7
[SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 2 issues ( = arrays) costing 2 points each4
[SA] Several paths (2 paths) - Simplify control structure or force the compiler to use masked instructions. There are 2 issues ( = paths) costing 1 point each.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
[SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points.2
[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 1 issues ( = data accesses) costing 2 point each.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
Warning! There is no dynamic data for this loop. Some checks can not been performed.0
780execPartial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access.21.472515.63
[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 1 issues ( = data accesses) costing 2 point each.2
228execInefficient vectorization.181.4710089.39
[SA] Presence of expensive instructions (GATHER/SCATTER) - Use array restructuring. There are 4 issues (= instructions) costing 4 points each.16
[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
991execPartial or unexisting vectorization - Use pragma to force vectorization and check potential dependencies between array access.150.7442.6217.32
[SA] Too many paths (8 paths) - Simplify control structure. There are 8 issues ( = paths) costing 1 point each with a malus of 4 points.12
[SA] Presence of calls - Inline either by compiler or by hand and use SVML for libm calls. There are 3 issues (= calls) costing 1 point each.3
Warning! Some static analysis are missing because the loop has too many paths. Use a higher value for --maximal_path_number option.0
1263execInefficient vectorization.20.7410050
[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
241execInefficient vectorization.40.74100100
[SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 2 issues ( = arrays) costing 2 points each4
Warning! There is no dynamic data for this loop. Some checks can not been performed.0
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