OV - exec - Loop 148

	Loop Id: 148	Module: exec	Source: advec_cell.cpp:45-48 [...]	Coverage: 1.33%

0x427c68 SEL	Z26.D, P1, Z5.D, Z19.D

0x427c6c ADD	X10, X10, X8

0x427c70 SDIVR	Z26.D, P0/M, Z26.D, Z25.D

0x427c74 ADD	Z27.D, Z6.D, Z26.D

0x427c78 MOVPRFX	Z28, Z25

0x427c7c MLS	Z28.D, P0/M, Z26.D, Z5.D

0x427c80 ADD	Z26.D, Z17.D, Z26.D

0x427c84 ADD	Z25.D, Z25.D, Z18.D

0x427c88 SXTW	Z27.D, P0/M, Z27.D

0x427c8c SXTW	Z26.D, P0/M, Z26.D

0x427c90 MOVPRFX	Z29, Z0

0x427c94 MUL	Z29.D, P0/M, Z29.D, Z27.D

0x427c98 MUL	Z26.D, P0/M, Z26.D, Z2.D

0x427c9c ADD	Z30.D, Z7.D, Z28.D

0x427ca0 ADD	Z28.D, Z16.D, Z28.D

0x427ca4 ADR	Z31.D, [Z20, Z30.D,SXTW #3]    [1]

0x427ca8 ADR	Z28.D, [Z21, Z28.D,SXTW #3]    [2]

0x427cac ADR	Z9.D, [Z21, Z30.D,SXTW #3]    [2]

0x427cb0 ADR	Z29.D, [Z31, Z29.D,LSL #3]    [5]

0x427cb4 MOVPRFX	Z31, Z1

0x427cb8 MUL	Z31.D, P0/M, Z31.D, Z27.D

0x427cbc LD1D	{Z29.D}, P1/Z, [V29.D]    [18]

0x427cc0 ADR	Z28.D, [Z28, Z31.D,LSL #3]    [16]

0x427cc4 ADR	Z31.D, [Z9, Z31.D,LSL #3]    [9]

0x427cc8 LD1D	{Z8.D}, P1/Z, [V28.D]    [15]

0x427ccc LD1D	{Z9.D}, P1/Z, [V31.D]    [3]

0x427cd0 FSUB	Z8.D, Z8.D, Z9.D

0x427cd4 ADR	Z9.D, [Z22, Z30.D,SXTW #3]    [7]

0x427cd8 ADR	Z26.D, [Z9, Z26.D,LSL #3]    [8]

0x427cdc LD1D	{Z26.D}, P1/Z, [V26.D]    [12]

0x427ce0 FADD	Z26.D, Z8.D, Z26.D

0x427ce4 MOVPRFX	Z8, Z2

0x427ce8 MUL	Z8.D, P0/M, Z8.D, Z27.D

0x427cec ADR	Z8.D, [Z9, Z8.D,LSL #3]    [8]

0x427cf0 LD1D	{Z8.D}, P1/Z, [V8.D]    [6]

0x427cf4 FSUB	Z26.D, Z26.D, Z8.D

0x427cf8 ADR	Z8.D, [Z23, Z30.D,SXTW #3]    [10]

0x427cfc FADD	Z26.D, Z29.D, Z26.D

0x427d00 MOVPRFX	Z29, Z3

0x427d04 MUL	Z29.D, P0/M, Z29.D, Z27.D

0x427d08 MUL	Z27.D, P0/M, Z27.D, Z4.D

0x427d0c ADR	Z29.D, [Z8, Z29.D,LSL #3]    [4]

0x427d10 ST1D	{Z26.D}, P1, [V29.D]    [17]

0x427d14 LD1D	{Z28.D}, P1/Z, [V28.D]    [15]

0x427d18 LD1D	{Z29.D}, P1/Z, [V31.D]    [3]

0x427d1c FSUB	Z28.D, Z28.D, Z29.D

0x427d20 FSUB	Z26.D, Z26.D, Z28.D

0x427d24 ADR	Z28.D, [Z24, Z30.D,SXTW #3]    [11]

0x427d28 ADR	Z27.D, [Z28, Z27.D,LSL #3]    [14]

0x427d2c ST1D	{Z26.D}, P1, [V27.D]    [13]

0x427d30 WHILELO	P1.D, X10, X9

0x427d34 B.MI	427c68

/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/advec_cell.cpp: 45 - 48

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

45:       for (int j = (y_min - 2 + 1); j < (y_max + 2 + 2); j++) {

46:         for (int i = (x_min - 2 + 1); i < (x_max + 2 + 2); i++) {

47:           pre_vol(i, j) = volume(i, j) + (vol_flux_x(i + 1, j + 0) - vol_flux_x(i, j) + vol_flux_y(i + 0, j + 1) - vol_flux_y(i, j));

48:           post_vol(i, j) = pre_vol(i, j) - (vol_flux_x(i + 1, j + 0) - vol_flux_x(i, j));

/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/context.h: 69 - 69

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

69:   T &operator()(size_t i, size_t j) const { return data[i + j * sizeX]; }

Coverage (%)	Name	Source Location	Module
►98.42+	__kmp_invoke_microtask		libomp.so
○	__kmp_invoke_task_func		libomp.so
○	__kmp_launch_thread		libomp.so
○	__kmp_launch_worker(void*)		libomp.so
○	start_thread		libc.so.6
○	thread_start		libc.so.6
►1.58+	__kmp_invoke_microtask		libomp.so
○	__kmp_invoke_task_func		libomp.so
○	__kmp_fork_call		libomp.so
○	__kmpc_fork_call		libomp.so
○	advec_cell_kernel(int, int, in[...]	advec_cell.cpp:54	exec
○	advec_cell_driver(global_varia[...]	advec_cell.cpp:232	exec
○	advection(global_variables&)	advection.cpp:50	exec
○	hydro(global_variables&, paral[...]	basic_string.h:1077	exec
○	main	clover_leaf.cpp:209	exec
○	__libc_start_call_main		libc.so.6
○	__libc_start_main		libc.so.6
○	_start	ostream:93	exec

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	1.32 - 1.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	3.08
Bottlenecks	P6, P7, P8,
Function	advec_cell_kernel(int, int, int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone .omp_outlined]
Source	advec_cell.cpp:45-48,context.h:69-69
Source loop unroll info	not unrolled or unrolled with no peel/tail loop
Source loop unroll confidence level	max
Unroll/vectorization loop type	NA
Unroll factor	NA
CQA cycles	20.00
CQA cycles if no scalar integer	20.00
CQA cycles if FP arith vectorized	20.00
CQA cycles if fully vectorized	15.13 - 20.00
Front-end cycles	6.50
P0 cycles	0.50
P1 cycles	0.50
P2 cycles	0.50
P3 cycles	0.25
P4 cycles	1.00
P5 cycles	0.25
P6 cycles	20.00
P7 cycles	20.00
P8 cycles	4.50
P9 cycles	4.50
P10 cycles	3.00
P11 cycles	3.00
P12 cycles	3.00
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	0.87 - 20.00
Inter-iter dependencies cycles	2
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	52.00
Nb uops	52.00
Nb loads	NA
Nb stores	2.00
Nb stack references	0.00
FLOP/cycle	1.20
Nb FLOP add-sub	24.00
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	14.48
Bytes prefetched	0.00
Bytes loaded	225.63
Bytes stored	64.00
Stride 0	0.00
Stride 1	0.00
Stride n	0.00
Stride unknown	13.00
Stride indirect	5.00
Vectorization ratio all	63.27
Vectorization ratio load	35.00
Vectorization ratio store	100.00
Vectorization ratio mul	100.00
Vectorization ratio add_sub	48.00
Vectorization ratio fma	NA
Vectorization ratio div_sqrt	100.00
Vectorization ratio other	37.50
Vector-efficiency ratio all	80.10
Vector-efficiency ratio load	51.25
Vector-efficiency ratio store	100.00
Vector-efficiency ratio mul	100.00
Vector-efficiency ratio add_sub	61.00
Vector-efficiency ratio fma	NA
Vector-efficiency ratio div_sqrt	100.00
Vector-efficiency ratio other	100.00

Metric	Value
CQA speedup if no scalar integer	1.00
CQA speedup if FP arith vectorized	1.00
CQA speedup if fully vectorized	1.32 - 1.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	3.08
Bottlenecks	P6, P7, P8,
Function	advec_cell_kernel(int, int, int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone .omp_outlined]
Source	advec_cell.cpp:45-48,context.h:69-69
Source loop unroll info	not unrolled or unrolled with no peel/tail loop
Source loop unroll confidence level	max
Unroll/vectorization loop type	NA
Unroll factor	NA
CQA cycles	20.00
CQA cycles if no scalar integer	20.00
CQA cycles if FP arith vectorized	20.00
CQA cycles if fully vectorized	15.13 - 20.00
Front-end cycles	6.50
P0 cycles	0.50
P1 cycles	0.50
P2 cycles	0.50
P3 cycles	0.25
P4 cycles	1.00
P5 cycles	0.25
P6 cycles	20.00
P7 cycles	20.00
P8 cycles	4.50
P9 cycles	4.50
P10 cycles	3.00
P11 cycles	3.00
P12 cycles	3.00
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	0.87 - 20.00
Inter-iter dependencies cycles	2
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	52.00
Nb uops	52.00
Nb loads	NA
Nb stores	2.00
Nb stack references	0.00
FLOP/cycle	1.20
Nb FLOP add-sub	24.00
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	14.48
Bytes prefetched	0.00
Bytes loaded	225.63
Bytes stored	64.00
Stride 0	0.00
Stride 1	0.00
Stride n	0.00
Stride unknown	13.00
Stride indirect	5.00
Vectorization ratio all	63.27
Vectorization ratio load	35.00
Vectorization ratio store	100.00
Vectorization ratio mul	100.00
Vectorization ratio add_sub	48.00
Vectorization ratio fma	NA
Vectorization ratio div_sqrt	100.00
Vectorization ratio other	37.50
Vector-efficiency ratio all	80.10
Vector-efficiency ratio load	51.25
Vector-efficiency ratio store	100.00
Vector-efficiency ratio mul	100.00
Vector-efficiency ratio add_sub	61.00
Vector-efficiency ratio fma	NA
Vector-efficiency ratio div_sqrt	100.00
Vector-efficiency ratio other	100.00

Path /

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

Function	advec_cell_kernel(int, int, int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone .omp_outlined]
Source file and lines	advec_cell.cpp:45-48
Module	exec

The loop is defined in:

/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/advec_cell.cpp:45-48
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/context.h:69

The related source loop is not unrolled or unrolled with no peel/tail loop.

gain
potential
hint
expert

Vectorization

Your loop is partially vectorized. 80% of vector register length is used (average across all VPU instructions).

Details

63% of VPU instructions are used in vector version (process two or more data elements in vector registers):

35% of VPU loads are used in vector version.
48% of VPU addition or subtraction instructions are used in vector version.
37% of VPU instructions that are not load, store, addition, subtraction nor multiply instructions are used in vector version.

No data for this section

Slow data structures access

Detected data structures (typically arrays) that cannot be efficiently read/written

Details

Constant unknown stride: 13 occurrence(s)
Irregular (variable stride) or indirect: 5 occurrence(s)

Non-unit stride (uncontiguous) accesses are not efficiently using data caches

Workaround

Try to reorganize arrays of structures to structures of arrays
Consider to permute loops (see vectorization gain report)
Try to remove indirect accesses. If applicable, precompute elements out of the innermost loop.

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

The binary loop is composed of 24 FP arithmetical operations:

24: addition or subtraction

The binary loop is loading 225 bytes. The binary loop is storing 64 bytes.

Arithmetic intensity

Arithmetic intensity is 0.08 FP operations per loaded or stored byte.

General properties

nb instructions	52
nb uops	52
loop length	208
used w registers	0
used x registers	3
used b registers	0
used h registers	0
used s registers	0
used d registers	0
used q registers	0
used v registers	6
used z registers	26
nb stack references	0

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	6.50 cycles
front end	6.50 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	0.50	0.50	0.50	0.25	1.00	0.25	20.00	20.00	4.50	4.50	3.00	3.00	3.00	0.00	0.00
cycles	0.50	0.50	0.50	0.25	1.00	0.25	20.00	20.00	4.50	4.50	3.00	3.00	3.00	0.00	0.00

Execution ports to units layout:

P0: BRU
P1: BRU
P2: ALU
P3: ALU
P4: ALU
P5: ALU
P6 (128 bits): VPU, FP store data, ALU, DIV/SQRT
P7 (128 bits): VPU, ALU, FP store data
P8 (128 bits): VPU, ALU, DIV/SQRT
P9 (128 bits): ALU, VPU
P10 (256 bits): store address, load
P11 (256 bits): store address, load
P12 (256 bits): load
P13 (64 bits): store data
P14 (64 bits): store data

Cycles executing div or sqrt instructions	0.87-20.00
Longest recurrence chain latency (RecMII)	2.00

Cycles summary

Front-end	6.50
Dispatch	20.00
DIV/SQRT	0.87-20.00
Data deps.	2.00
Overall L1	20.00

Vectorization ratios

INT

all	58%
load	35%
store	100%
mul	100%
add-sub	31%
fma	NA (no fma vectorizable/vectorized instructions)
other	44%

all	100%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	100%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	NA (no other vectorizable/vectorized instructions)

INT+FP

all	63%
load	35%
store	100%
mul	100%
add-sub	48%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	100%
other	37%

Vector efficiency ratios

INT

all	77%
load	51%
store	100%
mul	100%
add-sub	48%
fma	NA (no fma vectorizable/vectorized instructions)
other	100%

all	100%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	100%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	NA (no other vectorizable/vectorized instructions)

INT+FP

all	80%
load	51%
store	100%
mul	100%
add-sub	61%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	100%
other	100%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 20.00 cycles. At this rate:

11% of peak load performance is reached (11.28 out of 96.00 bytes loaded per cycle (GB/s @ 1GHz))
6% of peak store performance is reached (3.20 out of 48.00 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: 427c68

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	Latency	Recip. throughput	Vectorization
SEL Z26.D, P1, Z5.D, Z19.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADD X10, X10, X8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
SDIVR Z26.D, P0/M, Z26.D, Z25.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	7-20	0.87-20	vect (100.0%)
ADD Z27.D, Z6.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
MOVPRFX Z28, Z25	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MLS Z28.D, P0/M, Z26.D, Z5.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADD Z26.D, Z17.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADD Z25.D, Z25.D, Z18.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
SXTW Z27.D, P0/M, Z27.D	1	0	0	0	0	0	0	0	1	0	0	0	0	0	2	1	vect (100.0%)
SXTW Z26.D, P0/M, Z26.D	1	0	0	0	0	0	0	0	1	0	0	0	0	0	2	1	vect (100.0%)
MOVPRFX Z29, Z0	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z29.D, P0/M, Z29.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
MUL Z26.D, P0/M, Z26.D, Z2.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADD Z30.D, Z7.D, Z28.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADD Z28.D, Z16.D, Z28.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z31.D, [Z20, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z28.D, [Z21, Z28.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z9.D, [Z21, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z29.D, [Z31, Z29.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
MOVPRFX Z31, Z1	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z31.D, P0/M, Z31.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
LD1D {Z29.D}, P1/Z, [V29.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
ADR Z28.D, [Z28, Z31.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z31.D, [Z9, Z31.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
LD1D {Z8.D}, P1/Z, [V28.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
LD1D {Z9.D}, P1/Z, [V31.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FSUB Z8.D, Z8.D, Z9.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z9.D, [Z22, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z26.D, [Z9, Z26.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
LD1D {Z26.D}, P1/Z, [V26.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FADD Z26.D, Z8.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
MOVPRFX Z8, Z2	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z8.D, P0/M, Z8.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADR Z8.D, [Z9, Z8.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
LD1D {Z8.D}, P1/Z, [V8.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FSUB Z26.D, Z26.D, Z8.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z8.D, [Z23, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
FADD Z26.D, Z29.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
MOVPRFX Z29, Z3	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z29.D, P0/M, Z29.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
MUL Z27.D, P0/M, Z27.D, Z4.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADR Z29.D, [Z8, Z29.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ST1D {Z26.D}, P1, [V29.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.50	0.50	0	6	2	vect (100.0%)
LD1D {Z28.D}, P1/Z, [V28.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
LD1D {Z29.D}, P1/Z, [V31.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FSUB Z28.D, Z28.D, Z29.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
FSUB Z26.D, Z26.D, Z28.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z28.D, [Z24, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z27.D, [Z28, Z27.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ST1D {Z26.D}, P1, [V27.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.50	0.50	0	6	2	vect (100.0%)
WHILELO P1.D, X10, X9	1	0	0	0	0	1	0	0	0	0	0	0	0	0	3	2	N/A
B.MI 427c68 <_Z17advec_cell_kerneliiiiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_.omp_outlined+0x148>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A

Function	advec_cell_kernel(int, int, int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone .omp_outlined]
Source file and lines	advec_cell.cpp:45-48
Module	exec

The loop is defined in:

/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/advec_cell.cpp:45-48
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/context.h:69

The related source loop is not unrolled or unrolled with no peel/tail loop.

gain
potential
hint
expert

Vectorization

Your loop is partially vectorized. 80% of vector register length is used (average across all VPU instructions).

Details

63% of VPU instructions are used in vector version (process two or more data elements in vector registers):

35% of VPU loads are used in vector version.
48% of VPU addition or subtraction instructions are used in vector version.
37% of VPU instructions that are not load, store, addition, subtraction nor multiply instructions are used in vector version.

No data for this section

Slow data structures access

Detected data structures (typically arrays) that cannot be efficiently read/written

Details

Constant unknown stride: 13 occurrence(s)
Irregular (variable stride) or indirect: 5 occurrence(s)

Non-unit stride (uncontiguous) accesses are not efficiently using data caches

Workaround

Try to reorganize arrays of structures to structures of arrays
Consider to permute loops (see vectorization gain report)
Try to remove indirect accesses. If applicable, precompute elements out of the innermost loop.

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

The binary loop is composed of 24 FP arithmetical operations:

24: addition or subtraction

The binary loop is loading 225 bytes. The binary loop is storing 64 bytes.

Arithmetic intensity

Arithmetic intensity is 0.08 FP operations per loaded or stored byte.

General properties

nb instructions	52
nb uops	52
loop length	208
used w registers	0
used x registers	3
used b registers	0
used h registers	0
used s registers	0
used d registers	0
used q registers	0
used v registers	6
used z registers	26
nb stack references	0

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	6.50 cycles
front end	6.50 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	0.50	0.50	0.50	0.25	1.00	0.25	20.00	20.00	4.50	4.50	3.00	3.00	3.00	0.00	0.00
cycles	0.50	0.50	0.50	0.25	1.00	0.25	20.00	20.00	4.50	4.50	3.00	3.00	3.00	0.00	0.00

Execution ports to units layout:

P0: BRU
P1: BRU
P2: ALU
P3: ALU
P4: ALU
P5: ALU
P6 (128 bits): VPU, FP store data, ALU, DIV/SQRT
P7 (128 bits): VPU, ALU, FP store data
P8 (128 bits): VPU, ALU, DIV/SQRT
P9 (128 bits): ALU, VPU
P10 (256 bits): store address, load
P11 (256 bits): store address, load
P12 (256 bits): load
P13 (64 bits): store data
P14 (64 bits): store data

Cycles executing div or sqrt instructions	0.87-20.00
Longest recurrence chain latency (RecMII)	2.00

Cycles summary

Front-end	6.50
Dispatch	20.00
DIV/SQRT	0.87-20.00
Data deps.	2.00
Overall L1	20.00

Vectorization ratios

INT

all	58%
load	35%
store	100%
mul	100%
add-sub	31%
fma	NA (no fma vectorizable/vectorized instructions)
other	44%

all	100%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	100%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	NA (no other vectorizable/vectorized instructions)

INT+FP

all	63%
load	35%
store	100%
mul	100%
add-sub	48%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	100%
other	37%

Vector efficiency ratios

INT

all	77%
load	51%
store	100%
mul	100%
add-sub	48%
fma	NA (no fma vectorizable/vectorized instructions)
other	100%

all	100%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	100%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	NA (no other vectorizable/vectorized instructions)

INT+FP

all	80%
load	51%
store	100%
mul	100%
add-sub	61%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	100%
other	100%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 20.00 cycles. At this rate:

11% of peak load performance is reached (11.28 out of 96.00 bytes loaded per cycle (GB/s @ 1GHz))
6% of peak store performance is reached (3.20 out of 48.00 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: 427c68

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	Latency	Recip. throughput	Vectorization
SEL Z26.D, P1, Z5.D, Z19.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADD X10, X10, X8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
SDIVR Z26.D, P0/M, Z26.D, Z25.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	7-20	0.87-20	vect (100.0%)
ADD Z27.D, Z6.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
MOVPRFX Z28, Z25	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MLS Z28.D, P0/M, Z26.D, Z5.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADD Z26.D, Z17.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADD Z25.D, Z25.D, Z18.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
SXTW Z27.D, P0/M, Z27.D	1	0	0	0	0	0	0	0	1	0	0	0	0	0	2	1	vect (100.0%)
SXTW Z26.D, P0/M, Z26.D	1	0	0	0	0	0	0	0	1	0	0	0	0	0	2	1	vect (100.0%)
MOVPRFX Z29, Z0	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z29.D, P0/M, Z29.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
MUL Z26.D, P0/M, Z26.D, Z2.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADD Z30.D, Z7.D, Z28.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADD Z28.D, Z16.D, Z28.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z31.D, [Z20, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z28.D, [Z21, Z28.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z9.D, [Z21, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z29.D, [Z31, Z29.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
MOVPRFX Z31, Z1	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z31.D, P0/M, Z31.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
LD1D {Z29.D}, P1/Z, [V29.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
ADR Z28.D, [Z28, Z31.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z31.D, [Z9, Z31.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
LD1D {Z8.D}, P1/Z, [V28.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
LD1D {Z9.D}, P1/Z, [V31.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FSUB Z8.D, Z8.D, Z9.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z9.D, [Z22, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z26.D, [Z9, Z26.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
LD1D {Z26.D}, P1/Z, [V26.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FADD Z26.D, Z8.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
MOVPRFX Z8, Z2	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z8.D, P0/M, Z8.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADR Z8.D, [Z9, Z8.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
LD1D {Z8.D}, P1/Z, [V8.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FSUB Z26.D, Z26.D, Z8.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z8.D, [Z23, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
FADD Z26.D, Z29.D, Z26.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
MOVPRFX Z29, Z3	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (100.0%)
MUL Z29.D, P0/M, Z29.D, Z27.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
MUL Z27.D, P0/M, Z27.D, Z4.D	1	0	0	0	0	0	0	1	0	0	0	0	0	0	5	2	vect (100.0%)
ADR Z29.D, [Z8, Z29.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ST1D {Z26.D}, P1, [V29.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.50	0.50	0	6	2	vect (100.0%)
LD1D {Z28.D}, P1/Z, [V28.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
LD1D {Z29.D}, P1/Z, [V31.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.33	0.33	0.33	9	2	vect (100.0%)
FSUB Z28.D, Z28.D, Z29.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
FSUB Z26.D, Z26.D, Z28.D	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	vect (100.0%)
ADR Z28.D, [Z24, Z30.D,SXTW #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ADR Z27.D, [Z28, Z27.D,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0	0	0	2	0.50	scal (25.0%)
ST1D {Z26.D}, P1, [V27.D]	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0.50	0.50	0	6	2	vect (100.0%)
WHILELO P1.D, X10, X9	1	0	0	0	0	1	0	0	0	0	0	0	0	0	3	2	N/A
B.MI 427c68 <_Z17advec_cell_kerneliiiiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_S5_.omp_outlined+0x148>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A

Report Configuration

Vectorization

Details

Slow data structures access

Details

Workaround

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

Arithmetic intensity

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

Slow data structures access

Details

Workaround

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

Arithmetic intensity

General properties

Front-end

Back-end

Cycles summary

Vectorization ratios

Vector efficiency ratios

Cycles and memory resources usage

Front-end bottlenecks

ASM code