OV - exec - Loop 2620

	Loop Id: 2620	Module: exec	Source: par_strength.c:2011-2048	Coverage: 0.09%

0x2c6d30 MOV	-0x78(%RBP),%RCX

0x2c6d34 MOV	-0x70(%RBP),%RDX

0x2c6d38 INC	%R8

0x2c6d3b CMP	%R8,0x8(%RCX,%RDX,8)

0x2c6d40 JLE	2c6e70

0x2c6d46 MOV	-0x30(%RBP),%RCX

0x2c6d4a MOV	-0x60(%RBP),%RDX

0x2c6d4e MOV	(%RCX,%R8,8),%R10

0x2c6d52 CMPQ	$0,(%RDX,%R10,8)

0x2c6d57 JLE	2c6d87

0x2c6d59 MOV	-0xd0(%RBP),%RCX

0x2c6d60 MOV	(%RCX,%R10,8),%RCX

0x2c6d64 CMP	%R15,(%R13,%RCX,8)

0x2c6d69 JGE	2c6d87

0x2c6d6b MOV	-0x40(%RBP),%RDX

0x2c6d6f MOV	-0x90(%RBP),%RSI

0x2c6d76 MOV	%RDX,(%R13,%RCX,8)

0x2c6d7b MOV	-0x40(%RBP),%RDX

0x2c6d7f MOV	%RCX,(%RSI,%RDX,8)

0x2c6d83 INCQ	-0x40(%RBP)

0x2c6d87 MOV	-0x78(%RBP),%RDX

0x2c6d8b MOV	(%RDX,%R10,8),%RCX

0x2c6d8f MOV	0x8(%RDX,%R10,8),%RDX

0x2c6d94 CMP	%RDX,%RCX

0x2c6d97 JGE	2c6e00

0x2c6d99 MOV	0x78(%RBP),%RSI

0x2c6d9d MOV	0xc8(%RBP),%RDI

0x2c6da4 MOV	(%RSI),%R11

0x2c6da7 MOV	(%RDI),%RSI

0x2c6daa MOV	%RSI,-0x50(%RBP)

0x2c6dae JMP	2c6db8

  (2622) 0x2c6db0 INC	%RCX

  (2622) 0x2c6db3 CMP	%RDX,%RCX

  (2622) 0x2c6db6 JGE	2c6e00

  (2622) 0x2c6db8 MOV	-0x30(%RBP),%RSI

  (2622) 0x2c6dbc MOV	-0x60(%RBP),%RDI

  (2622) 0x2c6dc0 MOV	(%RSI,%RCX,8),%RSI

  (2622) 0x2c6dc4 CMPQ	$0,(%RDI,%RSI,8)

  (2622) 0x2c6dc9 JLE	2c6db0

  (2622) 0x2c6dcb MOV	(%R11,%RSI,8),%RSI

  (2622) 0x2c6dcf CMP	%R12,%RSI

  (2622) 0x2c6dd2 JE	2c6db0

  (2622) 0x2c6dd4 CMP	%R15,(%R13,%RSI,8)

  (2622) 0x2c6dd9 JGE	2c6db0

  (2622) 0x2c6ddb MOV	-0x40(%RBP),%RDX

  (2622) 0x2c6ddf MOV	-0x50(%RBP),%RDI

  (2622) 0x2c6de3 MOV	%RDX,(%R13,%RSI,8)

  (2622) 0x2c6de8 MOV	-0x40(%RBP),%RDX

  (2622) 0x2c6dec MOV	%RSI,(%RDI,%RDX,8)

  (2622) 0x2c6df0 MOV	-0x78(%RBP),%RSI

  (2622) 0x2c6df4 INCQ	-0x40(%RBP)

  (2622) 0x2c6df8 MOV	0x8(%RSI,%R10,8),%RDX

  (2622) 0x2c6dfd JMP	2c6db0

0x2c6e00 MOV	-0x80(%RBP),%RDX

0x2c6e04 MOV	(%RDX,%R10,8),%RCX

0x2c6e08 MOV	0x8(%RDX,%R10,8),%RSI

0x2c6e0d CMP	%RSI,%RCX

0x2c6e10 JGE	2c6d30

0x2c6e16 MOV	0x98(%RBP),%RDX

0x2c6e1d MOV	0xd0(%RBP),%R11

0x2c6e24 MOV	(%RDX),%RDX

0x2c6e27 MOV	(%R11),%RDI

0x2c6e2a JMP	2c6e3c

  (2621) 0x2c6e30 INC	%RCX

  (2621) 0x2c6e33 CMP	%RSI,%RCX

  (2621) 0x2c6e36 JGE	2c6d30

  (2621) 0x2c6e3c MOV	(%R9,%RCX,8),%R11

  (2621) 0x2c6e40 CMPQ	$0,(%RBX,%R11,8)

  (2621) 0x2c6e45 JLE	2c6e30

  (2621) 0x2c6e47 MOV	(%RDX,%R11,8),%R11

  (2621) 0x2c6e4b CMP	%RAX,(%R14,%R11,8)

  (2621) 0x2c6e4f JGE	2c6e30

  (2621) 0x2c6e51 MOV	-0x38(%RBP),%RSI

  (2621) 0x2c6e55 MOV	%RSI,(%R14,%R11,8)

  (2621) 0x2c6e59 MOV	-0x38(%RBP),%RSI

  (2621) 0x2c6e5d MOV	%R11,(%RDI,%RSI,8)

  (2621) 0x2c6e61 MOV	-0x80(%RBP),%R11

  (2621) 0x2c6e65 INCQ	-0x38(%RBP)

  (2621) 0x2c6e69 MOV	0x8(%R11,%R10,8),%RSI

  (2621) 0x2c6e6e JMP	2c6e30

/home/eoseret/qaas_runs_ZEN5/173-989-6379/intel/AMG/build/AMG/AMG/parcsr_ls/par_strength.c: 2011 - 2048

--------------------------------------------------------------------------------

2011:              for (jj1 = S_diag_i[i1]; jj1 < S_diag_i[i1+1]; jj1++)

2012:              {

2013:                  i2 = S_diag_j[jj1];

2014:                  if (CF_marker[i2] > 0)

2015:                  {

2016:                     index = fine_to_coarse[i2];

2017:                     if (S_marker[index] < jj_row_begin_diag)

2018:                     {

2019:                        S_marker[index] = num_nonzeros_diag;

2020:                        C_diag_j[num_nonzeros_diag] = index;

2021:                        num_nonzeros_diag++;

2022:                     }

2023:                  }

2024:                  for (jj2 = S_diag_i[i2]; jj2 < S_diag_i[i2+1]; jj2++)

2025:                  {

2026:                     i3 = S_diag_j[jj2];

2027:                     if (CF_marker[i3] > 0)

2028:                     {

2029:                        index = fine_to_coarse[i3];

2030:                        if (index != ic && S_marker[index] < jj_row_begin_diag)

2031:                        {

2032:                           S_marker[index] = num_nonzeros_diag;

2033:                           C_diag_j[num_nonzeros_diag] = index;

2034:                           num_nonzeros_diag++;

2035:                        }

2036:                     }

2037:                  }

2038:                  for (jj2 = S_offd_i[i2]; jj2 < S_offd_i[i2+1]; jj2++)

2039:                  {

2040:                     i3 = S_offd_j[jj2];

2041:                     if (CF_marker_offd[i3] > 0)

2042:                     {

2043:                        index = map_S_to_C[i3];

2044:                        if (S_marker_offd[index] < jj_row_begin_offd)

2045:                        {

2046:                           S_marker_offd[index] = num_nonzeros_offd;

2047:                           C_offd_j[num_nonzeros_offd] = index;

2048:                           num_nonzeros_offd++;

Coverage (%)	Name	Source Location	Module

min	med	avg	max

Percentile Index	10	20	30	40	50	60	70	80	90	100
Value

min	med	avg	max

Percentile Index	10	20	30	40	50	60	70	80	90	100
Value

Path /

Metric	Value
CQA speedup if no scalar integer	1.00
CQA speedup if FP arith vectorized	1.00
CQA speedup if fully vectorized	8.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.51
Bottlenecks	P6, P7, P8, P9,
Function	hypre_BoomerAMGCreate2ndS.omp_outlined.16
Source	par_strength.c:2011-2021,par_strength.c:2024-2024,par_strength.c:2038-2038
Source loop unroll info	NA
Source loop unroll confidence level	NA
Unroll/vectorization loop type	NA
Unroll factor	NA
CQA cycles	7.75
CQA cycles if no scalar integer	7.75
CQA cycles if FP arith vectorized	7.75
CQA cycles if fully vectorized	0.97
Front-end cycles	5.13
P0 cycles	2.33
P1 cycles	2.33
P2 cycles	2.33
P3 cycles	2.33
P4 cycles	2.33
P5 cycles	2.33
P6 cycles	7.75
P7 cycles	7.75
P8 cycles	7.75
P9 cycles	7.75
P10 cycles	0.00
P11 cycles	0.00
P12 cycles	0.00
P13 cycles	0.00
P14 cycles	0.00
P15 cycles	0.00
DIV/SQRT cycles	0.00
Inter-iter dependencies cycles	NA
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	41.00
Nb uops	41.00
Nb loads	28.00
Nb stores	4.00
Nb stack references	13.00
FLOP/cycle	0.00
Nb FLOP add-sub	0.00
Nb FLOP mul	0.00
Nb FLOP fma	0.00
Nb FLOP div	0.00
Nb FLOP rcp	0.00
Nb FLOP sqrt	0.00
Nb FLOP rsqrt	0.00
Bytes/cycle	33.03
Bytes prefetched	0.00
Bytes loaded	224.00
Bytes stored	32.00
Stride 0	NA
Stride 1	NA
Stride n	NA
Stride unknown	NA
Stride indirect	NA
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	NA
Vectorization ratio add_sub	NA
Vectorization ratio fma	NA
Vectorization ratio div_sqrt	NA
Vectorization ratio other	0.00
Vector-efficiency ratio all	12.50
Vector-efficiency ratio load	12.50
Vector-efficiency ratio store	12.50
Vector-efficiency ratio mul	NA
Vector-efficiency ratio add_sub	NA
Vector-efficiency ratio fma	NA
Vector-efficiency ratio div_sqrt	NA
Vector-efficiency ratio other	12.50

Metric	Value
CQA speedup if no scalar integer	1.00
CQA speedup if FP arith vectorized	1.00
CQA speedup if fully vectorized	8.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.51
Bottlenecks	P6, P7, P8, P9,
Function	hypre_BoomerAMGCreate2ndS.omp_outlined.16
Source	par_strength.c:2011-2021,par_strength.c:2024-2024,par_strength.c:2038-2038
Source loop unroll info	NA
Source loop unroll confidence level	NA
Unroll/vectorization loop type	NA
Unroll factor	NA
CQA cycles	7.75
CQA cycles if no scalar integer	7.75
CQA cycles if FP arith vectorized	7.75
CQA cycles if fully vectorized	0.97
Front-end cycles	5.13
P0 cycles	2.33
P1 cycles	2.33
P2 cycles	2.33
P3 cycles	2.33
P4 cycles	2.33
P5 cycles	2.33
P6 cycles	7.75
P7 cycles	7.75
P8 cycles	7.75
P9 cycles	7.75
P10 cycles	0.00
P11 cycles	0.00
P12 cycles	0.00
P13 cycles	0.00
P14 cycles	0.00
P15 cycles	0.00
DIV/SQRT cycles	0.00
Inter-iter dependencies cycles	NA
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	41.00
Nb uops	41.00
Nb loads	28.00
Nb stores	4.00
Nb stack references	13.00
FLOP/cycle	0.00
Nb FLOP add-sub	0.00
Nb FLOP mul	0.00
Nb FLOP fma	0.00
Nb FLOP div	0.00
Nb FLOP rcp	0.00
Nb FLOP sqrt	0.00
Nb FLOP rsqrt	0.00
Bytes/cycle	33.03
Bytes prefetched	0.00
Bytes loaded	224.00
Bytes stored	32.00
Stride 0	NA
Stride 1	NA
Stride n	NA
Stride unknown	NA
Stride indirect	NA
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	NA
Vectorization ratio add_sub	NA
Vectorization ratio fma	NA
Vectorization ratio div_sqrt	NA
Vectorization ratio other	0.00
Vector-efficiency ratio all	12.50
Vector-efficiency ratio load	12.50
Vector-efficiency ratio store	12.50
Vector-efficiency ratio mul	NA
Vector-efficiency ratio add_sub	NA
Vector-efficiency ratio fma	NA
Vector-efficiency ratio div_sqrt	NA
Vector-efficiency ratio other	12.50

Path /

Average path: Display a virtual path defined by average values of all real paths

Function	hypre_BoomerAMGCreate2ndS.omp_outlined.16
Source file and lines	par_strength.c:2011-2048
Module	exec

The loop is defined in /home/eoseret/qaas_runs_ZEN5/173-989-6379/intel/AMG/build/AMG/AMG/parcsr_ls/par_strength.c:2011-2048.

Analyzed code is defined in /home/eoseret/qaas_runs_ZEN5/173-989-6379/intel/AMG/build/AMG/AMG/parcsr_ls/par_strength.c:2011-2021,2024,2038.

Warnings:

Non-innermost loop: analyzing only self part (ignoring child loops).
Ignoring paths for analysis
Too many paths. If you really need to analyze all of the 60 paths individually, rerun with max-paths=60
RecMII not computed since number of paths is unknown or > max_paths
Streams not analyzed since number of paths is unknown or > max_paths

Try to simplify control and/or increase the maximum number of paths per function/loop through the 'max-paths-nb' option.

This loop has 60 execution paths.

The presence of multiple execution paths is typically the main/first bottleneck.
Try to simplify control inside loop: ideally, try to remove all conditional expressions, for example by (if applicable):

hoisting them (moving them outside the loop)
turning them into conditional moves, MIN or MAX

Ex: if (x<0) x=0 => x = (x<0 ? 0 : x) (or MAX(0,x) after defining the corresponding macro)

gain
potential
hint
expert

Vectorization

Your loop is not vectorized. 8 data elements could be processed at once in vector registers. By vectorizing your loop, you can lower the cost of an iteration from 7.75 to 0.97 cycles (8.00x speedup).

Details

All SSE/AVX instructions are used in scalar version (process only one data element in vector registers). Since your execution units are vector units, only a vectorized loop can use their full power.

Workaround

Try another compiler or update/tune your current one
Remove inter-iterations dependences from your loop and make it unit-stride:
- If your arrays have 2 or more dimensions, check whether elements are accessed contiguously and, otherwise, try to permute loops accordingly: C storage order is row-major: for(i) for(j) a[j][i] = b[j][i]; (slow, non stride 1) => for(i) for(j) a[i][j] = b[i][j]; (fast, stride 1)
- If your loop streams arrays of structures (AoS), try to use structures of arrays instead (SoA): for(i) a[i].x = b[i].x; (slow, non stride 1) => for(i) a.x[i] = b.x[i]; (fast, stride 1)

Execution units bottlenecks

Performance is limited by:

reading data from caches/RAM (load units are a bottleneck)
writing data to caches/RAM (the store unit is a bottleneck)

By removing all these bottlenecks, you can lower the cost of an iteration from 7.75 to 5.13 cycles (1.51x speedup).

Workaround

Read less array elements
Write less array elements
Provide more information to your compiler:
- hardcode the bounds of the corresponding 'for' loop
- use the 'restrict' C99 keyword

No data for this section

Type of elements and instruction set

No instructions are processing arithmetic or math operations on FP elements. This loop is probably writing/copying data or processing integer elements.

Matching between your loop (in the source code) and the binary loop

The binary loop does not contain any FP arithmetical operations. The binary loop is loading 224 bytes. The binary loop is storing 32 bytes.

General properties

nb instructions	41
nb uops	41
loop length	172
used x86 registers	10
used mmx registers	0
used xmm registers	0
used ymm registers	0
used zmm registers	0
nb stack references	13

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	5.13 cycles
front end	5.13 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14	P15
uops	2.33	2.33	2.33	2.33	2.33	2.33	7.75	7.75	7.75	7.75	0.00	0.00	0.00	0.00	0.00	0.00
cycles	2.33	2.33	2.33	2.33	2.33	2.33	7.75	7.75	7.75	7.75	0.00	0.00	0.00	0.00	0.00	0.00

Execution ports to units layout:

P0: ALU
P1: ALU
P2: ALU
P3: ALU, BRU
P4: ALU, BRU
P5: ALU, BRU
P6 (512 bits): store address, load
P7 (512 bits): store address, load
P8 (512 bits): store address, load
P9 (512 bits): store address, load
P10 (512 bits): VPU, DIV/SQRT
P11 (512 bits): VPU, DIV/SQRT
P12 (512 bits): VPU
P13 (512 bits): VPU
P14 (512 bits): FP store data
P15 (512 bits): FP store data

Cycles executing div or sqrt instructions

Cycles summary

Front-end	5.13
Dispatch	7.75
Overall L1	7.75

Vectorization ratios

all	0%
load	0%
store	0%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	0%

Vector efficiency ratios

all	12%
load	12%
store	12%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	12%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 7.75 cycles. At this rate:

11% of peak load performance is reached (28.90 out of 256.00 bytes loaded per cycle (GB/s @ 1GHz))
3% of peak store performance is reached (4.13 out of 128.00 bytes stored per cycle (GB/s @ 1GHz))

Front-end bottlenecks

Found no such bottlenecks.

ASM code

In the binary file, the address of the loop is: 2c6d46

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	Latency	Recip. throughput	Vectorization
MOV -0x78(%RBP),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV -0x70(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
INC %R8	1	0.17	0.17	0.17	0.17	0.17	0.17	0	0	0	0	1	0.17	N/A
CMP %R8,0x8(%RCX,%RDX,8)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.25	scal (12.5%)
JLE 2c6e70 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xf00>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV -0x30(%RBP),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV -0x60(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RCX,%R8,8),%R10	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMPQ $0,(%RDX,%R10,8)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.25	scal (12.5%)
JLE 2c6d87 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe17>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV -0xd0(%RBP),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RCX,%R10,8),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMP %R15,(%R13,%RCX,8)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.25	scal (12.5%)
JGE 2c6d87 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe17>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV -0x40(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV -0x90(%RBP),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV %RDX,(%R13,%RCX,8)	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	4	0.50	scal (12.5%)
MOV -0x40(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV %RCX,(%RSI,%RDX,8)	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	4	0.50	scal (12.5%)
INCQ -0x40(%RBP)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.50	scal (12.5%)
MOV -0x78(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDX,%R10,8),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0x8(%RDX,%R10,8),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMP %RDX,%RCX	1	0.17	0.17	0.17	0.17	0.17	0.17	0	0	0	0	1	0.17	scal (12.5%)
JGE 2c6e00 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe90>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV 0x78(%RBP),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0xc8(%RBP),%RDI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RSI),%R11	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDI),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV %RSI,-0x50(%RBP)	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	4	0.50	scal (12.5%)
JMP 2c6db8 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe48>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	0	1	N/A
MOV -0x80(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDX,%R10,8),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0x8(%RDX,%R10,8),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMP %RSI,%RCX	1	0.17	0.17	0.17	0.17	0.17	0.17	0	0	0	0	1	0.17	N/A
JGE 2c6d30 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xdc0>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV 0x98(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0xd0(%RBP),%R11	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDX),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%R11),%RDI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
JMP 2c6e3c <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xecc>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	0	1	N/A

Function	hypre_BoomerAMGCreate2ndS.omp_outlined.16
Source file and lines	par_strength.c:2011-2048
Module	exec

Non-innermost loop: analyzing only self part (ignoring child loops).
Ignoring paths for analysis
Too many paths. If you really need to analyze all of the 60 paths individually, rerun with max-paths=60
RecMII not computed since number of paths is unknown or > max_paths
Streams not analyzed since number of paths is unknown or > max_paths

hoisting them (moving them outside the loop)
turning them into conditional moves, MIN or MAX

Ex: if (x<0) x=0 => x = (x<0 ? 0 : x) (or MAX(0,x) after defining the corresponding macro)

gain
potential
hint
expert

Vectorization

Your loop is not vectorized. 8 data elements could be processed at once in vector registers. By vectorizing your loop, you can lower the cost of an iteration from 7.75 to 0.97 cycles (8.00x speedup).

Details

All SSE/AVX instructions are used in scalar version (process only one data element in vector registers). Since your execution units are vector units, only a vectorized loop can use their full power.

Workaround

Try another compiler or update/tune your current one
Remove inter-iterations dependences from your loop and make it unit-stride:
- If your arrays have 2 or more dimensions, check whether elements are accessed contiguously and, otherwise, try to permute loops accordingly: C storage order is row-major: for(i) for(j) a[j][i] = b[j][i]; (slow, non stride 1) => for(i) for(j) a[i][j] = b[i][j]; (fast, stride 1)
- If your loop streams arrays of structures (AoS), try to use structures of arrays instead (SoA): for(i) a[i].x = b[i].x; (slow, non stride 1) => for(i) a.x[i] = b.x[i]; (fast, stride 1)

Execution units bottlenecks

Performance is limited by:

reading data from caches/RAM (load units are a bottleneck)
writing data to caches/RAM (the store unit is a bottleneck)

By removing all these bottlenecks, you can lower the cost of an iteration from 7.75 to 5.13 cycles (1.51x speedup).

Workaround

Read less array elements
Write less array elements
Provide more information to your compiler:
- hardcode the bounds of the corresponding 'for' loop
- use the 'restrict' C99 keyword

No data for this section

Type of elements and instruction set

No instructions are processing arithmetic or math operations on FP elements. This loop is probably writing/copying data or processing integer elements.

Matching between your loop (in the source code) and the binary loop

The binary loop does not contain any FP arithmetical operations. The binary loop is loading 224 bytes. The binary loop is storing 32 bytes.

General properties

nb instructions	41
nb uops	41
loop length	172
used x86 registers	10
used mmx registers	0
used xmm registers	0
used ymm registers	0
used zmm registers	0
nb stack references	13

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	5.13 cycles
front end	5.13 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14	P15
uops	2.33	2.33	2.33	2.33	2.33	2.33	7.75	7.75	7.75	7.75	0.00	0.00	0.00	0.00	0.00	0.00
cycles	2.33	2.33	2.33	2.33	2.33	2.33	7.75	7.75	7.75	7.75	0.00	0.00	0.00	0.00	0.00	0.00

Execution ports to units layout:

P0: ALU
P1: ALU
P2: ALU
P3: ALU, BRU
P4: ALU, BRU
P5: ALU, BRU
P6 (512 bits): store address, load
P7 (512 bits): store address, load
P8 (512 bits): store address, load
P9 (512 bits): store address, load
P10 (512 bits): VPU, DIV/SQRT
P11 (512 bits): VPU, DIV/SQRT
P12 (512 bits): VPU
P13 (512 bits): VPU
P14 (512 bits): FP store data
P15 (512 bits): FP store data

Cycles executing div or sqrt instructions

Cycles summary

Front-end	5.13
Dispatch	7.75
Overall L1	7.75

Vectorization ratios

all	0%
load	0%
store	0%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	0%

Vector efficiency ratios

all	12%
load	12%
store	12%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	12%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 7.75 cycles. At this rate:

11% of peak load performance is reached (28.90 out of 256.00 bytes loaded per cycle (GB/s @ 1GHz))
3% of peak store performance is reached (4.13 out of 128.00 bytes stored per cycle (GB/s @ 1GHz))

Front-end bottlenecks

Found no such bottlenecks.

ASM code

In the binary file, the address of the loop is: 2c6d46

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	Latency	Recip. throughput	Vectorization
MOV -0x78(%RBP),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV -0x70(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
INC %R8	1	0.17	0.17	0.17	0.17	0.17	0.17	0	0	0	0	1	0.17	N/A
CMP %R8,0x8(%RCX,%RDX,8)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.25	scal (12.5%)
JLE 2c6e70 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xf00>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV -0x30(%RBP),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV -0x60(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RCX,%R8,8),%R10	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMPQ $0,(%RDX,%R10,8)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.25	scal (12.5%)
JLE 2c6d87 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe17>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV -0xd0(%RBP),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RCX,%R10,8),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMP %R15,(%R13,%RCX,8)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.25	scal (12.5%)
JGE 2c6d87 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe17>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV -0x40(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV -0x90(%RBP),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV %RDX,(%R13,%RCX,8)	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	4	0.50	scal (12.5%)
MOV -0x40(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV %RCX,(%RSI,%RDX,8)	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	4	0.50	scal (12.5%)
INCQ -0x40(%RBP)	1	0.17	0.17	0.17	0.17	0.17	0.17	0.25	0.25	0.25	0.25	1	0.50	scal (12.5%)
MOV -0x78(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDX,%R10,8),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0x8(%RDX,%R10,8),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMP %RDX,%RCX	1	0.17	0.17	0.17	0.17	0.17	0.17	0	0	0	0	1	0.17	scal (12.5%)
JGE 2c6e00 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe90>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV 0x78(%RBP),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0xc8(%RBP),%RDI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RSI),%R11	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDI),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV %RSI,-0x50(%RBP)	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	4	0.50	scal (12.5%)
JMP 2c6db8 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xe48>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	0	1	N/A
MOV -0x80(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDX,%R10,8),%RCX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0x8(%RDX,%R10,8),%RSI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
CMP %RSI,%RCX	1	0.17	0.17	0.17	0.17	0.17	0.17	0	0	0	0	1	0.17	N/A
JGE 2c6d30 <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xdc0>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	1	0.50-1	N/A
MOV 0x98(%RBP),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV 0xd0(%RBP),%R11	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%RDX),%RDX	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
MOV (%R11),%RDI	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	3	0.25	N/A
JMP 2c6e3c <hypre_BoomerAMGCreate2ndS.omp_outlined.16+0xecc>	1	0	0	0	0.33	0.33	0.33	0	0	0	0	0	1	N/A

Report Configuration

Vectorization

Details

Workaround

Execution units bottlenecks

Workaround

Type of elements and instruction set

Matching between your loop (in the source code) and the binary loop

General properties

Front-end

Back-end

Cycles summary

Vectorization ratios

Vector efficiency ratios

Cycles and memory resources usage

Front-end bottlenecks

ASM code

Vectorization

Details

Workaround

Execution units bottlenecks

Workaround

Type of elements and instruction set

Matching between your loop (in the source code) and the binary loop

General properties

Front-end

Back-end

Cycles summary

Vectorization ratios

Vector efficiency ratios

Cycles and memory resources usage

Front-end bottlenecks

ASM code