OV - exec - Loop 640

	Loop Id: 640	Module: exec	Source: viscosity.cpp:39-64 [...]	Coverage: 2.46%

0x45b824 FABS	D28, D27

0x45b828 FMAXNM	D26, D28, D30

0x45b82c FMUL	D19, D23, D26

0x45b830 LDR	X21, [X16]    [8]

0x45b834 LDR	X18, [X16, #16]    [8]

0x45b838 FMUL	D16, D19, D19

0x45b83c MADD	X1, X11, X21, X1

0x45b840 LDR	D24, [X18, X1,LSL #3]    [10]

0x45b844 FMADD	D27, D25, D25, D16

0x45b848 FADD	D6, D24, D24

0x45b84c FSQRT	D20, D27

0x45b850 FMUL	D0, D0, D20

0x45b854 FMUL	D17, D17, D20

0x45b858 FDIV	D22, D0, D25

0x45b85c FDIV	D21, D17, D19

0x45b860 FABS	D18, D22

0x45b864 FABS	D5, D21

0x45b868 FMINNM	D3, D18, D5

0x45b86c FMUL	D1, D3, D7

0x45b870 FMUL	D4, D1, D1

0x45b874 FMUL	D23, D6, D4

0x45b878 STR	D23, [X9, X0,LSL #3]    [5]

0x45b87c ADD	X0, X0, #1

0x45b880 ORR	X1, XZR, X3

0x45b884 ADD	X2, X2, #8

0x45b888 ADD	X3, X3, #1

0x45b88c CMP	X0, X15

0x45b890 B.EQ	45b9c8

0x45b894 LDR	D22, [X6, X0,LSL #3]    [2]

0x45b898 SUB	X18, X2, #8

0x45b89c LDR	D3, [X4, X0,LSL #3]    [12]

0x45b8a0 LDR	D21, [X4, X1,LSL #3]    [12]

0x45b8a4 LDR	D23, [X6, X1,LSL #3]    [2]

0x45b8a8 LDR	D27, [X5, X0,LSL #3]    [1]

0x45b8ac FADD	D1, D22, D3

0x45b8b0 LDR	D4, [X5, X1,LSL #3]    [1]

0x45b8b4 FADD	D0, D21, D3

0x45b8b8 LDR	D5, [X7, X1,LSL #3]    [3]

0x45b8bc FADD	D2, D23, D21

0x45b8c0 FADD	D6, D23, D22

0x45b8c4 LDR	D28, [X7, X0,LSL #3]    [3]

0x45b8c8 FADD	D24, D27, D4

0x45b8cc LDUR	D23, [X2, #496]    [9]

0x45b8d0 FADD	D7, D5, D4

0x45b8d4 LDR	D26, [X18, X10,LSL #3]    [11]

0x45b8d8 FSUB	D16, D1, S2

0x45b8dc FSUB	D18, D6, S0

0x45b8e0 FADD	D17, D28, D27

0x45b8e4 FADD	D20, D28, D5

0x45b8e8 LDR	D0, [X8, X1,LSL #3]    [4]

0x45b8ec LDR	D19, [X18, X14,LSL #3]    [11]

0x45b8f0 LDR	D25, [X8, X0,LSL #3]    [4]

0x45b8f4 LDR	D4, [X2]    [9]

0x45b8f8 FSUB	D1, D17, S7

0x45b8fc FSUB	D3, D24, S20

0x45b900 FDIV	D6, D31, D0

0x45b904 LDR	D17, [X13]    [7]

0x45b908 FSUB	D22, D19, S26

0x45b90c LDR	D24, [X12]    [6]

0x45b910 FADD	D27, D0, D25

0x45b914 FSUB	D5, D4, S23

0x45b918 MOVI	D23, #0

0x45b91c FDIV	D7, D31, D17

0x45b920 FMUL	D26, D18, D17

0x45b924 FADD	D19, D17, D24

0x45b928 FDIV	D28, D5, D27

0x45b92c FMUL	D21, D16, D6

0x45b930 FMADD	D16, D1, D0, D26

0x45b934 FDIV	D27, D22, D19

0x45b938 FMADD	D20, D3, D7, D21

0x45b93c FMUL	D21, D28, D28

0x45b940 FABS	D2, D28

0x45b944 FMAXNM	D25, D2, D30

0x45b948 FMUL	D22, D27, D27

0x45b94c FMUL	D1, D1, D21

0x45b950 FMUL	D5, D28, D27

0x45b954 FMUL	D18, D18, D22

0x45b958 FADD	D4, D22, D21

0x45b95c FMAXNM	D24, D4, D30

0x45b960 FMUL	D3, D18, D7

0x45b964 FMADD	D6, D1, D6, D3

0x45b968 FMADD	D2, D20, D5, D6

0x45b96c FDIV	D7, D2, D24

0x45b970 FCMPE	D7, D23

0x45b974 FCCMPE	D16, D29, #0, #13

0x45b978 CSINC	W21, WZR, WZR, #11

0x45b97c CBNZ	W21, 45b878

0x45b980 FCMPE	D28, #0

0x45b984 FMOV	D23, #1.0000000

0x45b988 B.GE	45b824

0x45b98c FCMPE	D25, #0

0x45b990 FMOV	D23, #-1.0000000

0x45b994 FNEG	D25, D25

0x45b998 B.GT	45b824

0x45b99c FMOV	D23, #1.0000000

0x45b9a0 B	45b824

/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]; }

/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/viscosity.cpp: 39 - 64

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

39:       double ugrad = (xvel0(i + 1, j + 0) + xvel0(i + 1, j + 1)) - (xvel0(i, j) + xvel0(i + 0, j + 1));

40:       double vgrad = (yvel0(i + 0, j + 1) + yvel0(i + 1, j + 1)) - (yvel0(i, j) + yvel0(i + 1, j + 0));

41:       double div = (celldx[i] * (ugrad) + celldy[j] * (vgrad));

42:       double strain2 = 0.5 * (xvel0(i + 0, j + 1) + xvel0(i + 1, j + 1) - xvel0(i, j) - xvel0(i + 1, j + 0)) / celldy[j] +

43:                        0.5 * (yvel0(i + 1, j + 0) + yvel0(i + 1, j + 1) - yvel0(i, j) - yvel0(i + 0, j + 1)) / celldx[i];

44:       double pgradx = (pressure(i + 1, j + 0) - pressure(i - 1, j + 0)) / (celldx[i] + celldx[i + 1]);

45:       double pgrady = (pressure(i + 0, j + 1) - pressure(i + 0, j - 1)) / (celldy[j] + celldy[j + 2]);

46:       double pgradx2 = pgradx * pgradx;

47:       double pgrady2 = pgrady * pgrady;

48:       double limiter = ((0.5 * (ugrad) / celldx[i]) * pgradx2 + (0.5 * (vgrad) / celldy[j]) * pgrady2 + strain2 * pgradx * pgrady) /

49:                        std::fmax(pgradx2 + pgrady2, g_small);

50:       if ((limiter > 0.0) || (div >= 0.0)) {

51:         viscosity(i, j) = 0.0;

52:       } else {

53:         double dirx = 1.0;

54:         if (pgradx < 0.0) dirx = -1.0;

55:         pgradx = dirx * std::fmax(g_small, std::fabs(pgradx));

56:         double diry = 1.0;

57:         if (pgradx < 0.0) diry = -1.0;

58:         pgrady = diry * std::fmax(g_small, std::fabs(pgrady));

59:         double pgrad = std::sqrt(pgradx * pgradx + pgrady * pgrady);

60:         double xgrad = std::fabs(celldx[i] * pgrad / pgradx);

61:         double ygrad = std::fabs(celldy[j] * pgrad / pgrady);

62:         double grad = std::fmin(xgrad, ygrad);

63:         double grad2 = grad * grad;

64:         viscosity(i, j) = 2.0 * density0(i, j) * grad2 * limiter * limiter;

Coverage (%)	Name	Source Location	Module
►98.41+	omp_fulfill_event		libgomp.so.1.0.0
○	start_thread		libc.so.6
○	thread_start		libc.so.6
►1.59+	GOMP_parallel		libgomp.so.1.0.0
○	viscosity(global_variables&)	viscosity.cpp:76	exec
○	timestep(global_variables&, pa[...]	timestep.cpp:64	exec
○	hydro(global_variables&, paral[...]	basic_string.h:1076	exec
○	main	clover_leaf.cpp:209	exec
○	__libc_start_call_main		libc.so.6
○	__libc_start_main		libc.so.6
○	_start	clover_leaf.cpp:51	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	2.34 - 4.20
CQA speedup if FP arith vectorized	2.00
CQA speedup if fully vectorized	2.24 - 2.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.79
Bottlenecks
Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source	context.h:69-69,viscosity.cpp:39-64
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	14.25 - 25.54
CQA cycles if no scalar integer	6.08
CQA cycles if FP arith vectorized	6.71 - 12.77
CQA cycles if fully vectorized	6.35 - 12.77
Front-end cycles	10.81
P0 cycles	1.75
P1 cycles	1.75
P2 cycles	1.94
P3 cycles	1.94
P4 cycles	1.94
P5 cycles	1.94
P6 cycles	14.25
P7 cycles	14.25
P8 cycles	14.25
P9 cycles	14.25
P10 cycles	6.58
P11 cycles	6.25
P12 cycles	6.42
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	12.70 - 25.54
Inter-iter dependencies cycles	0
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	86.50
Nb uops	86.50
Nb loads	NA
Nb stores	1.00
Nb stack references	0.00
FLOP/cycle	3.35 - 1.87
Nb FLOP add-sub	17.75
Nb FLOP mul	13.25
Nb FLOP fma	4.75
Nb FLOP div	6.50
Nb FLOP rcp	0.00
Nb FLOP sqrt	0.75
Nb FLOP rsqrt	0.00
Bytes/cycle	0.00
Bytes prefetched	0.00
Bytes loaded	0.00
Bytes stored	0.00
Stride 0	2.75
Stride 1	0.00
Stride n	4.00
Stride unknown	1.00
Stride indirect	2.75
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	0.00
Vectorization ratio add_sub	0.00
Vectorization ratio fma	0.00
Vectorization ratio div_sqrt	0.00
Vectorization ratio other	0.00
Vector-efficiency ratio all	24.84
Vector-efficiency ratio load	25.00
Vector-efficiency ratio store	25.00
Vector-efficiency ratio mul	25.00
Vector-efficiency ratio add_sub	25.00
Vector-efficiency ratio fma	25.00
Vector-efficiency ratio div_sqrt	25.00
Vector-efficiency ratio other	24.06

Metric	Value
CQA speedup if no scalar integer	1.76 - 3.00
CQA speedup if FP arith vectorized	2.00
CQA speedup if fully vectorized	2.34 - 2.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.71
Bottlenecks	P6, P8,
Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source	context.h:69-69,viscosity.cpp:39-64
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	10.25 - 17.48
CQA cycles if no scalar integer	5.83
CQA cycles if FP arith vectorized	5.83 - 8.74
CQA cycles if fully vectorized	4.38 - 8.74
Front-end cycles	8.25
P0 cycles	1.00
P1 cycles	1.00
P2 cycles	1.75
P3 cycles	1.75
P4 cycles	1.75
P5 cycles	1.75
P6 cycles	10.25
P7 cycles	10.25
P8 cycles	10.25
P9 cycles	10.25
P10 cycles	5.83
P11 cycles	5.50
P12 cycles	5.67
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	8.76 - 17.48
Inter-iter dependencies cycles	0
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	66.00
Nb uops	66.00
Nb loads	NA
Nb stores	1.00
Nb stack references	0.00
FLOP/cycle	3.71 - 2.17
Nb FLOP add-sub	17.00
Nb FLOP mul	8.00
Nb FLOP fma	4.00
Nb FLOP div	5.00
Nb FLOP rcp	0.00
Nb FLOP sqrt	0.00
Nb FLOP rsqrt	0.00
Bytes/cycle	0.00
Bytes prefetched	0.00
Bytes loaded	0.00
Bytes stored	0.00
Stride 0	2.00
Stride 1	0.00
Stride n	4.00
Stride unknown	1.00
Stride indirect	2.00
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	0.00
Vectorization ratio add_sub	0.00
Vectorization ratio fma	0.00
Vectorization ratio div_sqrt	0.00
Vectorization ratio other	0.00
Vector-efficiency ratio all	24.79
Vector-efficiency ratio load	25.00
Vector-efficiency ratio store	25.00
Vector-efficiency ratio mul	25.00
Vector-efficiency ratio add_sub	25.00
Vector-efficiency ratio fma	25.00
Vector-efficiency ratio div_sqrt	25.00
Vector-efficiency ratio other	23.44

Metric	Value
CQA speedup if no scalar integer	2.43 - 4.58
CQA speedup if FP arith vectorized	2.00
CQA speedup if fully vectorized	2.14 - 2.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.88
Bottlenecks	P6, P8,
Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source	context.h:69-69,viscosity.cpp:39-64
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	15.00 - 28.22
CQA cycles if no scalar integer	6.17
CQA cycles if FP arith vectorized	7.01 - 14.11
CQA cycles if fully vectorized	7.01 - 14.11
Front-end cycles	11.25
P0 cycles	1.50
P1 cycles	1.50
P2 cycles	2.00
P3 cycles	2.00
P4 cycles	2.00
P5 cycles	2.00
P6 cycles	15.00
P7 cycles	15.00
P8 cycles	15.00
P9 cycles	15.00
P10 cycles	6.83
P11 cycles	6.50
P12 cycles	6.67
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	14.01 - 28.22
Inter-iter dependencies cycles	0
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	90.00
Nb uops	90.00
Nb loads	NA
Nb stores	1.00
Nb stack references	0.00
FLOP/cycle	3.40 - 1.81
Nb FLOP add-sub	18.00
Nb FLOP mul	15.00
Nb FLOP fma	5.00
Nb FLOP div	7.00
Nb FLOP rcp	0.00
Nb FLOP sqrt	1.00
Nb FLOP rsqrt	0.00
Bytes/cycle	0.00
Bytes prefetched	0.00
Bytes loaded	0.00
Bytes stored	0.00
Stride 0	3.00
Stride 1	0.00
Stride n	4.00
Stride unknown	1.00
Stride indirect	3.00
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	0.00
Vectorization ratio add_sub	0.00
Vectorization ratio fma	0.00
Vectorization ratio div_sqrt	0.00
Vectorization ratio other	0.00
Vector-efficiency ratio all	24.85
Vector-efficiency ratio load	25.00
Vector-efficiency ratio store	25.00
Vector-efficiency ratio mul	25.00
Vector-efficiency ratio add_sub	25.00
Vector-efficiency ratio fma	25.00
Vector-efficiency ratio div_sqrt	25.00
Vector-efficiency ratio other	24.17

Metric	Value
CQA speedup if no scalar integer	2.59 - 4.58
CQA speedup if FP arith vectorized	2.00
CQA speedup if fully vectorized	2.28 - 2.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.76
Bottlenecks	P6, P8,
Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source	context.h:69-69,viscosity.cpp:39-64
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	16.00 - 28.22
CQA cycles if no scalar integer	6.17
CQA cycles if FP arith vectorized	7.01 - 14.11
CQA cycles if fully vectorized	7.01 - 14.11
Front-end cycles	12.00
P0 cycles	2.50
P1 cycles	2.50
P2 cycles	2.00
P3 cycles	2.00
P4 cycles	2.00
P5 cycles	2.00
P6 cycles	16.00
P7 cycles	16.00
P8 cycles	16.00
P9 cycles	16.00
P10 cycles	6.83
P11 cycles	6.50
P12 cycles	6.67
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	14.01 - 28.22
Inter-iter dependencies cycles	0
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	96.00
Nb uops	96.00
Nb loads	NA
Nb stores	1.00
Nb stack references	0.00
FLOP/cycle	3.19 - 1.81
Nb FLOP add-sub	18.00
Nb FLOP mul	15.00
Nb FLOP fma	5.00
Nb FLOP div	7.00
Nb FLOP rcp	0.00
Nb FLOP sqrt	1.00
Nb FLOP rsqrt	0.00
Bytes/cycle	0.00
Bytes prefetched	0.00
Bytes loaded	0.00
Bytes stored	0.00
Stride 0	3.00
Stride 1	0.00
Stride n	4.00
Stride unknown	1.00
Stride indirect	3.00
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	0.00
Vectorization ratio add_sub	0.00
Vectorization ratio fma	0.00
Vectorization ratio div_sqrt	0.00
Vectorization ratio other	0.00
Vector-efficiency ratio all	24.85
Vector-efficiency ratio load	25.00
Vector-efficiency ratio store	25.00
Vector-efficiency ratio mul	25.00
Vector-efficiency ratio add_sub	25.00
Vector-efficiency ratio fma	25.00
Vector-efficiency ratio div_sqrt	25.00
Vector-efficiency ratio other	24.34

Metric	Value
CQA speedup if no scalar integer	2.55 - 4.58
CQA speedup if FP arith vectorized	2.00
CQA speedup if fully vectorized	2.25 - 2.00
CQA speedup if no inter-iteration dependency	NA
CQA speedup if next bottleneck killed	1.79
Bottlenecks	P6, P8,
Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source	context.h:69-69,viscosity.cpp:39-64
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	15.75 - 28.22
CQA cycles if no scalar integer	6.17
CQA cycles if FP arith vectorized	7.01 - 14.11
CQA cycles if fully vectorized	7.01 - 14.11
Front-end cycles	11.75
P0 cycles	2.00
P1 cycles	2.00
P2 cycles	2.00
P3 cycles	2.00
P4 cycles	2.00
P5 cycles	2.00
P6 cycles	15.75
P7 cycles	15.75
P8 cycles	15.75
P9 cycles	15.75
P10 cycles	6.83
P11 cycles	6.50
P12 cycles	6.67
P13 cycles	0.00
P14 cycles	0.00
DIV/SQRT cycles	14.01 - 28.22
Inter-iter dependencies cycles	0
FE+BE cycles (UFS)	NA
Stall cycles (UFS)	NA
Nb insns	94.00
Nb uops	94.00
Nb loads	NA
Nb stores	1.00
Nb stack references	0.00
FLOP/cycle	3.24 - 1.81
Nb FLOP add-sub	18.00
Nb FLOP mul	15.00
Nb FLOP fma	5.00
Nb FLOP div	7.00
Nb FLOP rcp	0.00
Nb FLOP sqrt	1.00
Nb FLOP rsqrt	0.00
Bytes/cycle	0.00
Bytes prefetched	0.00
Bytes loaded	0.00
Bytes stored	0.00
Stride 0	3.00
Stride 1	0.00
Stride n	4.00
Stride unknown	1.00
Stride indirect	3.00
Vectorization ratio all	0.00
Vectorization ratio load	0.00
Vectorization ratio store	0.00
Vectorization ratio mul	0.00
Vectorization ratio add_sub	0.00
Vectorization ratio fma	0.00
Vectorization ratio div_sqrt	0.00
Vectorization ratio other	0.00
Vector-efficiency ratio all	24.85
Vector-efficiency ratio load	25.00
Vector-efficiency ratio store	25.00
Vector-efficiency ratio mul	25.00
Vector-efficiency ratio add_sub	25.00
Vector-efficiency ratio fma	25.00
Vector-efficiency ratio div_sqrt	25.00
Vector-efficiency ratio other	24.31

Path /

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

Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source file and lines	viscosity.cpp:39-64
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/context.h:69
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/viscosity.cpp:39-64

The related source loop is not unrolled or unrolled with no peel/tail loop.
This loop has 4 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. Only 24% of vector register length is used (average across all VPU instructions). By vectorizing your loop, you can lower the cost of an iteration from 25.54 to 12.77 cycles (2.00x speedup).

Details

All VPU 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)

Expensive FP math instructions/calls

Detected performance impact from expensive FP math instructions/calls. By removing/reexpressing them, you can lower the cost of an iteration from 25.54 to 12.44 cycles (2.05x speedup).

FMA

Detected 4.75 FMA (fused multiply-add) operations. Presence of both ADD/SUB and MUL operations.

Workaround

Try to change order in which elements are evaluated (using parentheses) in arithmetic expressions containing both ADD/SUB and MUL operations to enable your compiler to generate FMA instructions wherever possible. For instance a + b*c is a valid FMA (MUL then ADD). However (a+b)* c cannot be translated into an FMA (ADD then MUL).

Slow data structures access

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

Details

Constant unknown stride: 1 occurrence(s)
Constant non-unit stride: 4 occurrence(s)
Irregular (variable stride) or indirect: 2 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 47.75 FP arithmetical operations:

22.50: addition or subtraction (4 inside FMA instructions)
18: multiply (4 inside FMA instructions)
6.50: divide
0.75: square root

The binary loop does not load or store any data.

General properties

nb instructions	86.50
nb uops	86.50
loop length	346
used w registers	2
used x registers	19.25
used b registers	0
used h registers	0
used s registers	6
used d registers	24
used q registers	0
used v registers	0
used z registers	0
nb stack references	0
ADD-SUB / MUL ratio	1.43

Front-end

MACRO FUSION NOT POSSIBLE

micro-operation queue	10.81 cycles
front end	10.81 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	1.75	1.75	1.94	1.94	1.94	1.94	14.25	14.25	14.25	14.25	6.58	6.25	6.42	0.00	0.00
cycles	1.75	1.75	1.94	1.94	1.94	1.94	14.25	14.25	14.25	14.25	6.58	6.25	6.42	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	12.70-25.54
Longest recurrence chain latency (RecMII)	0.00

Cycles summary

Front-end	10.81
Dispatch	14.25
DIV/SQRT	12.70-25.54
Data deps.	0.00
Overall L1	14.25-25.54

Vectorization ratios

INT

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

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

INT+FP

all	0%
load	0%
store	0%
mul	0%
add-sub	0%
fma	0%
div/sqrt	0%
other	0%

Vector efficiency ratios

INT

all	24%
load	25%
store	25%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	25%
fma	NA (no fma vectorizable/vectorized instructions)
other	20%

all	25%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	25%

INT+FP

all	24%
load	25%
store	25%
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	24%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 25.54 cycles.

Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source file and lines	viscosity.cpp:39-64
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/context.h:69
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/viscosity.cpp:39-64

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

Code clean check

Detected a slowdown caused by scalar integer instructions (typically used for address computation). By removing them, you can lower the cost of an iteration from 17.48 to 5.83 cycles (3.00x speedup).

Workaround

Try to reorganize arrays of structures to structures of arrays
Consider to permute loops (see vectorization gain report)

Vectorization

Details

All VPU 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)

Expensive FP math instructions/calls

Detected performance impact from expensive FP math instructions/calls. By removing/reexpressing them, you can lower the cost of an iteration from 17.48 to 9.00 cycles (1.94x speedup).

FMA

Detected 4 FMA (fused multiply-add) operations. Presence of both ADD/SUB and MUL operations.

Workaround

Slow data structures access

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

Details

Constant unknown stride: 1 occurrence(s)
Constant non-unit stride: 4 occurrence(s)
Irregular (variable stride) or indirect: 2 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 38 FP arithmetical operations:

21: addition or subtraction (4 inside FMA instructions)
12: multiply (4 inside FMA instructions)
5: divide

The binary loop does not load or store any data.

General properties

nb instructions	66
nb uops	66
loop length	264
used w registers	2
used x registers	17
used b registers	0
used h registers	0
used s registers	6
used d registers	24
used q registers	0
used v registers	0
used z registers	0
nb stack references	0
ADD-SUB / MUL ratio	2.13

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	8.25 cycles
front end	8.25 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	1.00	1.00	1.75	1.75	1.75	1.75	10.25	10.25	10.25	10.25	5.83	5.50	5.67	0.00	0.00
cycles	1.00	1.00	1.75	1.75	1.75	1.75	10.25	10.25	10.25	10.25	5.83	5.50	5.67	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	8.76-17.48
Longest recurrence chain latency (RecMII)	0.00

Cycles summary

Front-end	8.25
Dispatch	10.25
DIV/SQRT	8.76-17.48
Data deps.	0.00
Overall L1	10.25-17.48

Vectorization ratios

INT

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

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

INT+FP

all	0%
load	0%
store	0%
mul	0%
add-sub	0%
fma	0%
div/sqrt	0%
other	0%

Vector efficiency ratios

INT

all	24%
load	25%
store	25%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	25%
fma	NA (no fma vectorizable/vectorized instructions)
other	20%

all	25%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	25%

INT+FP

all	24%
load	25%
store	25%
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	23%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 17.48 cycles.

Front-end bottlenecks

Found no such bottlenecks.

ASM code

In the binary file, the address of the loop is: 45b894

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	Latency	Recip. throughput	Vectorization
STR D23, [X9, X0,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0.50	0.50	0	2	0.50	scal (25.0%)
ADD X0, X0, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ORR X1, XZR, X3	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X2, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X3, X3, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (25.0%)
CMP X0, X15	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.33	scal (25.0%)
B.EQ 45b9c8 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x328>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
LDR D22, [X6, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
SUB X18, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
LDR D3, [X4, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D21, [X4, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D23, [X6, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D27, [X5, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D1, D22, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D4, [X5, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D0, D21, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D5, [X7, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D2, D23, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D6, D23, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D28, [X7, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D24, D27, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDUR D23, [X2, #496]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D7, D5, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D26, [X18, X10,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D16, D1, S2	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D18, D6, S0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D17, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D20, D28, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D0, [X8, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D19, [X18, X14,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D25, [X8, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D4, [X2]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D1, D17, S7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D3, D24, S20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D6, D31, D0	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
LDR D17, [X13]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D22, D19, S26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D24, [X12]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D27, D0, D25	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D5, D4, S23	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
MOVI D23, #0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D7, D31, D17	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D26, D18, D17	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D19, D17, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D28, D5, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D21, D16, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D16, D1, D0, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D27, D22, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMADD D20, D3, D7, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMUL D21, D28, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FABS D2, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D25, D2, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D22, D27, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D1, D1, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D5, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D18, D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D4, D22, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D24, D4, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D3, D18, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D6, D1, D6, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMADD D2, D20, D5, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D7, D2, D24	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FCMPE D7, D23	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FCCMPE D16, D29, #0, #13	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
CSINC W21, WZR, WZR, #11	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (12.5%)
CBNZ W21, 45b878 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x1d8>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A

Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source file and lines	viscosity.cpp:39-64
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/context.h:69
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/viscosity.cpp:39-64

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

Code clean check

Detected a slowdown caused by scalar integer instructions (typically used for address computation). By removing them, you can lower the cost of an iteration from 28.22 to 6.17 cycles (4.58x speedup).

Workaround

Try to reorganize arrays of structures to structures of arrays
Consider to permute loops (see vectorization gain report)

Vectorization

Details

All VPU 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)

Expensive FP math instructions/calls

Detected performance impact from expensive FP math instructions/calls. By removing/reexpressing them, you can lower the cost of an iteration from 28.22 to 13.00 cycles (2.17x speedup).

FMA

Detected 5 FMA (fused multiply-add) operations. Presence of both ADD/SUB and MUL operations.

Workaround

Slow data structures access

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

Details

Constant unknown stride: 1 occurrence(s)
Constant non-unit stride: 4 occurrence(s)
Irregular (variable stride) or indirect: 3 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 51 FP arithmetical operations:

23: addition or subtraction (5 inside FMA instructions)
20: multiply (5 inside FMA instructions)
7: divide
1: square root

The binary loop does not load or store any data.

General properties

nb instructions	90
nb uops	90
loop length	360
used w registers	2
used x registers	20
used b registers	0
used h registers	0
used s registers	6
used d registers	24
used q registers	0
used v registers	0
used z registers	0
nb stack references	0
ADD-SUB / MUL ratio	1.20

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	11.25 cycles
front end	11.25 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	1.50	1.50	2.00	2.00	2.00	2.00	15.00	15.00	15.00	15.00	6.83	6.50	6.67	0.00	0.00
cycles	1.50	1.50	2.00	2.00	2.00	2.00	15.00	15.00	15.00	15.00	6.83	6.50	6.67	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	14.01-28.22
Longest recurrence chain latency (RecMII)	0.00

Cycles summary

Front-end	11.25
Dispatch	15.00
DIV/SQRT	14.01-28.22
Data deps.	0.00
Overall L1	15.00-28.22

Vectorization ratios

INT

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

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

INT+FP

all	0%
load	0%
store	0%
mul	0%
add-sub	0%
fma	0%
div/sqrt	0%
other	0%

Vector efficiency ratios

INT

all	24%
load	25%
store	25%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	25%
fma	NA (no fma vectorizable/vectorized instructions)
other	20%

all	25%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	25%

INT+FP

all	24%
load	25%
store	25%
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	24%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 28.22 cycles.

Front-end bottlenecks

Found no such bottlenecks.

ASM code

In the binary file, the address of the loop is: 45b894

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	Latency	Recip. throughput	Vectorization
FABS D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D26, D28, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D19, D23, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
LDR X21, [X16]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	4	0.33	scal (25.0%)
LDR X18, [X16, #16]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	4	0.33	N/A
FMUL D16, D19, D19	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
MADD X1, X11, X21, X1	1	0	0	0	0	1	0	0	0	0	0	0	0	0	2	1	N/A
LDR D24, [X18, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FMADD D27, D25, D25, D16	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FADD D6, D24, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSQRT D20, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-16	1.75-3.75	scal (25.0%)
FMUL D0, D0, D20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D17, D17, D20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FDIV D22, D0, D25	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FDIV D21, D17, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FABS D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FABS D5, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMINNM D3, D18, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D1, D3, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D4, D1, D1	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D23, D6, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
STR D23, [X9, X0,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0.50	0.50	0	2	0.50	scal (25.0%)
ADD X0, X0, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ORR X1, XZR, X3	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X2, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X3, X3, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (25.0%)
CMP X0, X15	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.33	scal (25.0%)
B.EQ 45b9c8 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x328>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
LDR D22, [X6, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
SUB X18, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
LDR D3, [X4, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D21, [X4, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D23, [X6, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D27, [X5, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D1, D22, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D4, [X5, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D0, D21, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D5, [X7, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D2, D23, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D6, D23, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D28, [X7, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D24, D27, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDUR D23, [X2, #496]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D7, D5, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D26, [X18, X10,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D16, D1, S2	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D18, D6, S0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D17, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D20, D28, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D0, [X8, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D19, [X18, X14,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D25, [X8, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D4, [X2]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D1, D17, S7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D3, D24, S20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D6, D31, D0	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
LDR D17, [X13]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D22, D19, S26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D24, [X12]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D27, D0, D25	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D5, D4, S23	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
MOVI D23, #0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D7, D31, D17	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D26, D18, D17	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D19, D17, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D28, D5, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D21, D16, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D16, D1, D0, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D27, D22, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMADD D20, D3, D7, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMUL D21, D28, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FABS D2, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D25, D2, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D22, D27, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D1, D1, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D5, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D18, D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D4, D22, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D24, D4, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D3, D18, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D6, D1, D6, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMADD D2, D20, D5, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D7, D2, D24	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FCMPE D7, D23	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FCCMPE D16, D29, #0, #13	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
CSINC W21, WZR, WZR, #11	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (12.5%)
CBNZ W21, 45b878 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x1d8>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
FCMPE D28, #0	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FMOV D23, #1.0000000	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
B.GE 45b824 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x184>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A

Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source file and lines	viscosity.cpp:39-64
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/context.h:69
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/viscosity.cpp:39-64

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

Code clean check

Detected a slowdown caused by scalar integer instructions (typically used for address computation). By removing them, you can lower the cost of an iteration from 28.22 to 6.17 cycles (4.58x speedup).

Workaround

Try to reorganize arrays of structures to structures of arrays
Consider to permute loops (see vectorization gain report)

Vectorization

Details

All VPU 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)

Expensive FP math instructions/calls

Detected performance impact from expensive FP math instructions/calls. By removing/reexpressing them, you can lower the cost of an iteration from 28.22 to 14.00 cycles (2.02x speedup).

FMA

Detected 5 FMA (fused multiply-add) operations. Presence of both ADD/SUB and MUL operations.

Workaround

Slow data structures access

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

Details

Constant unknown stride: 1 occurrence(s)
Constant non-unit stride: 4 occurrence(s)
Irregular (variable stride) or indirect: 3 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 51 FP arithmetical operations:

23: addition or subtraction (5 inside FMA instructions)
20: multiply (5 inside FMA instructions)
7: divide
1: square root

The binary loop does not load or store any data.

General properties

nb instructions	96
nb uops	96
loop length	384
used w registers	2
used x registers	20
used b registers	0
used h registers	0
used s registers	6
used d registers	24
used q registers	0
used v registers	0
used z registers	0
nb stack references	0
ADD-SUB / MUL ratio	1.20

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	12.00 cycles
front end	12.00 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	2.50	2.50	2.00	2.00	2.00	2.00	16.00	16.00	16.00	16.00	6.83	6.50	6.67	0.00	0.00
cycles	2.50	2.50	2.00	2.00	2.00	2.00	16.00	16.00	16.00	16.00	6.83	6.50	6.67	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	14.01-28.22
Longest recurrence chain latency (RecMII)	0.00

Cycles summary

Front-end	12.00
Dispatch	16.00
DIV/SQRT	14.01-28.22
Data deps.	0.00
Overall L1	16.00-28.22

Vectorization ratios

INT

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

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

INT+FP

all	0%
load	0%
store	0%
mul	0%
add-sub	0%
fma	0%
div/sqrt	0%
other	0%

Vector efficiency ratios

INT

all	24%
load	25%
store	25%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	25%
fma	NA (no fma vectorizable/vectorized instructions)
other	20%

all	25%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	25%

INT+FP

all	24%
load	25%
store	25%
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	24%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 28.22 cycles.

Front-end bottlenecks

Found no such bottlenecks.

ASM code

In the binary file, the address of the loop is: 45b894

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	Latency	Recip. throughput	Vectorization
FABS D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D26, D28, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D19, D23, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
LDR X21, [X16]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	4	0.33	scal (25.0%)
LDR X18, [X16, #16]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	4	0.33	N/A
FMUL D16, D19, D19	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
MADD X1, X11, X21, X1	1	0	0	0	0	1	0	0	0	0	0	0	0	0	2	1	N/A
LDR D24, [X18, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FMADD D27, D25, D25, D16	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FADD D6, D24, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSQRT D20, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-16	1.75-3.75	scal (25.0%)
FMUL D0, D0, D20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D17, D17, D20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FDIV D22, D0, D25	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FDIV D21, D17, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FABS D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FABS D5, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMINNM D3, D18, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D1, D3, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D4, D1, D1	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D23, D6, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
STR D23, [X9, X0,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0.50	0.50	0	2	0.50	scal (25.0%)
ADD X0, X0, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ORR X1, XZR, X3	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X2, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X3, X3, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (25.0%)
CMP X0, X15	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.33	scal (25.0%)
B.EQ 45b9c8 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x328>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
LDR D22, [X6, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
SUB X18, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
LDR D3, [X4, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D21, [X4, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D23, [X6, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D27, [X5, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D1, D22, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D4, [X5, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D0, D21, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D5, [X7, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D2, D23, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D6, D23, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D28, [X7, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D24, D27, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDUR D23, [X2, #496]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D7, D5, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D26, [X18, X10,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D16, D1, S2	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D18, D6, S0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D17, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D20, D28, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D0, [X8, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D19, [X18, X14,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D25, [X8, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D4, [X2]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D1, D17, S7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D3, D24, S20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D6, D31, D0	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
LDR D17, [X13]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D22, D19, S26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D24, [X12]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D27, D0, D25	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D5, D4, S23	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
MOVI D23, #0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D7, D31, D17	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D26, D18, D17	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D19, D17, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D28, D5, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D21, D16, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D16, D1, D0, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D27, D22, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMADD D20, D3, D7, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMUL D21, D28, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FABS D2, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D25, D2, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D22, D27, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D1, D1, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D5, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D18, D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D4, D22, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D24, D4, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D3, D18, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D6, D1, D6, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMADD D2, D20, D5, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D7, D2, D24	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FCMPE D7, D23	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FCCMPE D16, D29, #0, #13	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
CSINC W21, WZR, WZR, #11	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (12.5%)
CBNZ W21, 45b878 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x1d8>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
FCMPE D28, #0	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FMOV D23, #1.0000000	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
B.GE 45b824 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x184>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
FCMPE D25, #0	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FMOV D23, #-1.0000000	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FNEG D25, D25	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
B.GT 45b824 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x184>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
FMOV D23, #1.0000000	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
B 45b824 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x184>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A

Function	viscosity_kernel(int, int, int, int, clover::Buffer1D&, clover::Buffer1D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&, clover::Buffer2D&) [clone ._omp_fn.0]
Source file and lines	viscosity.cpp:39-64
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/context.h:69
/home/eoseret/qaas/qaas_runs/178-219-7589/intel/CloverLeaf2.0-CXX/build/CloverLeaf2.0-CXX/src/omp/viscosity.cpp:39-64

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

Code clean check

Detected a slowdown caused by scalar integer instructions (typically used for address computation). By removing them, you can lower the cost of an iteration from 28.22 to 6.17 cycles (4.58x speedup).

Workaround

Try to reorganize arrays of structures to structures of arrays
Consider to permute loops (see vectorization gain report)

Vectorization

Details

All VPU 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)

Expensive FP math instructions/calls

Detected performance impact from expensive FP math instructions/calls. By removing/reexpressing them, you can lower the cost of an iteration from 28.22 to 13.75 cycles (2.05x speedup).

FMA

Detected 5 FMA (fused multiply-add) operations. Presence of both ADD/SUB and MUL operations.

Workaround

Slow data structures access

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

Details

Constant unknown stride: 1 occurrence(s)
Constant non-unit stride: 4 occurrence(s)
Irregular (variable stride) or indirect: 3 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 51 FP arithmetical operations:

23: addition or subtraction (5 inside FMA instructions)
20: multiply (5 inside FMA instructions)
7: divide
1: square root

The binary loop does not load or store any data.

General properties

nb instructions	94
nb uops	94
loop length	376
used w registers	2
used x registers	20
used b registers	0
used h registers	0
used s registers	6
used d registers	24
used q registers	0
used v registers	0
used z registers	0
nb stack references	0
ADD-SUB / MUL ratio	1.20

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	11.75 cycles
front end	11.75 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	P13	P14
uops	2.00	2.00	2.00	2.00	2.00	2.00	15.75	15.75	15.75	15.75	6.83	6.50	6.67	0.00	0.00
cycles	2.00	2.00	2.00	2.00	2.00	2.00	15.75	15.75	15.75	15.75	6.83	6.50	6.67	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	14.01-28.22
Longest recurrence chain latency (RecMII)	0.00

Cycles summary

Front-end	11.75
Dispatch	15.75
DIV/SQRT	14.01-28.22
Data deps.	0.00
Overall L1	15.75-28.22

Vectorization ratios

INT

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

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

INT+FP

all	0%
load	0%
store	0%
mul	0%
add-sub	0%
fma	0%
div/sqrt	0%
other	0%

Vector efficiency ratios

INT

all	24%
load	25%
store	25%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	25%
fma	NA (no fma vectorizable/vectorized instructions)
other	20%

all	25%
load	NA (no load vectorizable/vectorized instructions)
store	NA (no store vectorizable/vectorized instructions)
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	25%

INT+FP

all	24%
load	25%
store	25%
mul	25%
add-sub	25%
fma	25%
div/sqrt	25%
other	24%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each iteration of the binary loop takes 28.22 cycles.

Front-end bottlenecks

Found no such bottlenecks.

ASM code

In the binary file, the address of the loop is: 45b894

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	P12	Latency	Recip. throughput	Vectorization
FABS D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D26, D28, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D19, D23, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
LDR X21, [X16]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	4	0.33	scal (25.0%)
LDR X18, [X16, #16]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	4	0.33	N/A
FMUL D16, D19, D19	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
MADD X1, X11, X21, X1	1	0	0	0	0	1	0	0	0	0	0	0	0	0	2	1	N/A
LDR D24, [X18, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FMADD D27, D25, D25, D16	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FADD D6, D24, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSQRT D20, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-16	1.75-3.75	scal (25.0%)
FMUL D0, D0, D20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D17, D17, D20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FDIV D22, D0, D25	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FDIV D21, D17, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FABS D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FABS D5, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMINNM D3, D18, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D1, D3, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D4, D1, D1	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D23, D6, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
STR D23, [X9, X0,LSL #3]	1	0	0	0	0	0	0	0.50	0.50	0	0	0.50	0.50	0	2	0.50	scal (25.0%)
ADD X0, X0, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ORR X1, XZR, X3	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X2, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
ADD X3, X3, #1	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (25.0%)
CMP X0, X15	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.33	scal (25.0%)
B.EQ 45b9c8 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x328>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
LDR D22, [X6, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
SUB X18, X2, #8	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	N/A
LDR D3, [X4, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D21, [X4, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D23, [X6, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D27, [X5, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D1, D22, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D4, [X5, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D0, D21, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D5, [X7, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D2, D23, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D6, D23, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D28, [X7, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D24, D27, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDUR D23, [X2, #496]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D7, D5, D4	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D26, [X18, X10,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D16, D1, S2	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D18, D6, S0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D17, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FADD D20, D28, D5	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D0, [X8, X1,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D19, [X18, X14,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D25, [X8, X0,LSL #3]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
LDR D4, [X2]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D1, D17, S7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D3, D24, S20	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D6, D31, D0	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
LDR D17, [X13]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FSUB D22, D19, S26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
LDR D24, [X12]	1	0	0	0	0	0	0	0	0	0	0	0.33	0.33	0.33	6	0.33	scal (25.0%)
FADD D27, D0, D25	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FSUB D5, D4, S23	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
MOVI D23, #0	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D7, D31, D17	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D26, D18, D17	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D19, D17, D24	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FDIV D28, D5, D27	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMUL D21, D16, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D16, D1, D0, D26	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D27, D22, D19	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FMADD D20, D3, D7, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMUL D21, D28, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FABS D2, D28	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D25, D2, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D22, D27, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D1, D1, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D5, D28, D27	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMUL D18, D18, D22	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FADD D4, D22, D21	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMAXNM D24, D4, D30	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FMUL D3, D18, D7	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	3	0.25	scal (25.0%)
FMADD D6, D1, D6, D3	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FMADD D2, D20, D5, D6	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	4	0.25	scal (25.0%)
FDIV D7, D2, D24	1	0	0	0	0	0	0	0.50	0	0.50	0	0	0	0	7-15	1.75-3.50	scal (25.0%)
FCMPE D7, D23	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FCCMPE D16, D29, #0, #13	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
CSINC W21, WZR, WZR, #11	1	0	0	0.25	0.25	0.25	0.25	0	0	0	0	0	0	0	1	0.25	scal (12.5%)
CBNZ W21, 45b878 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x1d8>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
FCMPE D28, #0	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FMOV D23, #1.0000000	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
B.GE 45b824 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x184>	1	0.50	0.50	0	0	0	0	0	0	0	0	0	0	0	1	0.50	N/A
FCMPE D25, #0	1	0	0	0	0	0	0	1	0	0	0	0	0	0	2	1	scal (25.0%)
FMOV D23, #-1.0000000	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
FNEG D25, D25	1	0	0	0	0	0	0	0.25	0.25	0.25	0.25	0	0	0	2	0.25	scal (25.0%)
B.GT 45b824 <_Z16viscosity_kerneliiiiRN6clover8Buffer1DIdEES2_RNS_8Buffer2DIdEES5_S5_S5_S5_._omp_fn.0+0x184>	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

Workaround

Expensive FP math instructions/calls

FMA

Workaround

Slow data structures access

Details

Workaround

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

Code clean check

Workaround

Vectorization

Details

Workaround

Expensive FP math instructions/calls

FMA

Workaround

Slow data structures access

Details

Workaround

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

Code clean check

Workaround

Vectorization

Details

Workaround

Expensive FP math instructions/calls

FMA

Workaround

Slow data structures access

Details

Workaround

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

Code clean check

Workaround

Vectorization

Details

Workaround

Expensive FP math instructions/calls

FMA

Workaround

Slow data structures access

Details

Workaround

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