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[ 4 / 4 ] Application profile is long enough (1846.61 s)
To have good quality measurements, it is advised that the application profiling time is greater than 10 seconds.
[ 0.00 / 3 ] Some functions are compiled with a low optimization level (O0 or O1)
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.
[ 0.00 / 3 ] Most of time spent in analyzed modules comes from functions without compilation information
Functions without compilation information (typically not compiled with -g) cumulate 100.00% of the time spent in analyzed modules. Check that -g is present. Remark: if -g is indeed used, this can also be due to some compiler built-in functions (typically math) or statically linked libraries. This warning can be ignored in that case.
[ 0.00 / 3 ] Compilation of some functions is not optimized for the target processor
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 0.58 % 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 (83.68%)
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% (10.51%), representing an hotspot for the application
[ 4 / 4 ] Enough time of the experiment time spent in analyzed innermost loops (79.22%)
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% (0.00%) is spend in BLAS1 operations
It could be more efficient to inline by hand BLAS1 operations
[ 3 / 3 ] Cumulative Outermost/In between loops coverage (4.46%) lower than cumulative innermost loop coverage (79.22%)
Having cumulative Outermost/In between loops coverage greater than cumulative innermost loop coverage will make loop optimization more complex
[ 2 / 2 ] Less than 10% (0.00%) is spend in Libm/SVML (special functions)
[ 2 / 2 ] Less than 10% (0.00%) is spend in BLAS2 operations
BLAS2 calls usually could make a poor cache usage and could benefit from inlining.
Loop ID | Analysis | Penalty Score |
---|---|---|
►Loop 7942 - engine_linux64_intel_ifx_impi | Execution Time: 10 % - Vectorization Ratio: 0.00 % - Vector Length Use: 12.50 % | |
►Loop Computation Issues | 9 | |
○ | [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 |
○ | [DA] Low iteration count (1.94 < 10) - Perform full unroll. Use compiler pragmas. Use PGO/FDO compiler options. Force compiler to use masked instructions. This issue costs 5 points. | 5 |
►Control Flow Issues | 5 | |
○ | [DA] Low iteration count (1.94 < 10) - Perform full unroll. Use compiler pragmas. Use PGO/FDO compiler options. Force compiler to use masked instructions. This issue costs 5 points. | 5 |
►Loop 17194 - engine_linux64_intel_ifx_impi | Execution Time: 9 % - Vectorization Ratio: 29.27 % - Vector Length Use: 16.16 % | |
►Data Access Issues | 6 | |
○ | [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] Ratio time (ORIG)/time (DL1) is greater than 3 (3.87) - 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 4 points due to the ORIG/DL1 ratio. | 4 |
►Loop 16541 - engine_linux64_intel_ifx_impi | Execution Time: 4 % - Vectorization Ratio: 0.00 % - Vector Length Use: 12.33 % | |
►Data Access Issues | 16 | |
○ | [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] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 3 issues ( = indirect data accesses) costing 4 point each. | 12 |
○ | [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 |
►Vectorization Roadblocks | 14 | |
○ | [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] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 3 issues ( = indirect data accesses) costing 4 point each. | 12 |
►Loop 8227 - engine_linux64_intel_ifx_impi | Execution Time: 3 % - Vectorization Ratio: 95.08 % - Vector Length Use: 45.70 % | |
►Loop Computation Issues | 4 | |
○ | [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 |
►Data Access Issues | 46 | |
○ | [SA] Inefficient vectorization: more than 10% of the vector loads instructions are unaligned - When allocating arrays, don’t forget to align them. There are 0 issues ( = arrays) costing 2 points each | 0 |
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BLEND/MERGE, SHUFFLE/PERM, BROADCAST) - Simplify data access and try to get stride 1 access. There are 36 issues (= instructions) costing 1 point each. | 36 |
○ | [DA] Ratio time (ORIG)/time (DL1) is greater than 3 (9.91) - 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 10 points due to the ORIG/DL1 ratio. | 10 |
►Inefficient Vectorization | 36 | |
○ | [SA] Presence of special instructions executing on a single port (INSERT/EXTRACT, BLEND/MERGE, SHUFFLE/PERM, BROADCAST) - Simplify data access and try to get stride 1 access. There are 36 issues (= instructions) costing 1 point each. | 36 |
►Loop 110841 - engine_linux64_intel_ifx_impi | Execution Time: 3 % - Vectorization Ratio: 100.00 % - Vector Length Use: 50.00 % | |
►Vectorization Roadblocks | 0 | |
○ | [SA] Out of user code (executable and library listed in external_libraries ). This issue is a warning. | 0 |
►Loop 16588 - engine_linux64_intel_ifx_impi | Execution Time: 2 % - Vectorization Ratio: 0.00 % - Vector Length Use: 12.50 % | |
►Loop Computation Issues | 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 |
►Control Flow Issues | 3 | |
○ | [SA] Several paths (3 paths) - Simplify control structure or force the compiler to use masked instructions. There are 3 issues ( = paths) costing 1 point each. | 3 |
►Data Access Issues | 6 | |
○ | [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] More than 20% of the loads are accessing the stack - Perform loop splitting to decrease pressure on registers. This issue costs 2 points. | 2 |
►Vectorization Roadblocks | 7 | |
○ | [SA] Several paths (3 paths) - Simplify control structure or force the compiler to use masked instructions. There are 3 issues ( = paths) costing 1 point each. | 3 |
○ | [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 |
►Loop 8307 - engine_linux64_intel_ifx_impi | Execution Time: 1 % - Vectorization Ratio: 9.09 % - Vector Length Use: 13.07 % | |
►Loop Computation Issues | 6 | |
○ | [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] 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 |
►Loop 52226 - engine_linux64_intel_ifx_impi | Execution Time: 1 % - Vectorization Ratio: 96.44 % - Vector Length Use: 39.41 % | |
►Loop Computation Issues | 6 | |
○ | [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] 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 |
►Control Flow Issues | 2 | |
○ | [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 |
►Data Access Issues | 29 | |
○ | [SA] Presence of indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 2 issues ( = indirect data accesses) costing 4 point each. | 8 |
○ | [SA] Presence of expensive instructions (GATHER/SCATTER) - Use array restructuring. There are 5 issues (= instructions) costing 4 points each. | 20 |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 1 issues (= instructions) costing 1 point each. | 1 |
►Vectorization Roadblocks | 10 | |
○ | [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 indirect accesses - Use array restructuring or gather instructions to lower the cost. There are 2 issues ( = indirect data accesses) costing 4 point each. | 8 |
►Inefficient Vectorization | 23 | |
○ | [SA] Presence of expensive instructions (GATHER/SCATTER) - Use array restructuring. There are 5 issues (= instructions) costing 4 points each. | 20 |
○ | [SA] Presence of special instructions executing on a single port (BROADCAST) - Simplify data access and try to get stride 1 access. There are 1 issues (= instructions) costing 1 point each. | 1 |
○ | [SA] Inefficient vectorization: use of masked instructions - Simplify control structure. The issue costs 2 points. | 2 |
►Loop 17134 - engine_linux64_intel_ifx_impi | Execution Time: 1 % - Vectorization Ratio: 100.00 % - Vector Length Use: 50.00 % | |
►Loop Computation Issues | 6 | |
○ | [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] 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 |
►Loop 16960 - engine_linux64_intel_ifx_impi | Execution Time: 1 % - Vectorization Ratio: 100.00 % - Vector Length Use: 50.00 % | |
►Loop Computation Issues | 6 | |
○ | [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] 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 |
►Data Access Issues | 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 |