OV - exec - Function hypre_BoomerAMGCoarsenPMIS._omp

	Function: hypre_BoomerAMGCoarsenPMIS._omp_fn.3	Module: exec	Source: par_coarsen.c:2139-2142	Coverage (incl. loops): 0.02% \| (excl. loops): 0.00%

/home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c: 2139 - 2142

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

2139: #pragma omp parallel for private(i) HYPRE_SMP_SCHEDULE

2140:    for (i=0; i < num_variables; i++)

2141:    {

2142:      measure_array[i] = measure_array_temp[i];

0x42e330 PUSH	%RBP

0x42e331 MOV	%RSP,%RBP

0x42e334 PUSH	%R12

0x42e336 MOV	%RDI,%R12

0x42e339 PUSH	%RBX

0x42e33a CALL	4110b0 <omp_get_num_threads@plt>

0x42e33f MOV	%EAX,%EBX

0x42e341 CALL	4111f0 <omp_get_thread_num@plt>

0x42e346 MOVSXD	%EAX,%RCX

0x42e349 MOV	(%R12),%RAX

0x42e34d MOVSXD	%EBX,%RSI

0x42e350 CQTO

0x42e352 IDIV	%RSI

0x42e355 CMP	%RDX,%RCX

0x42e358 JL	42e4a0

0x42e35e IMUL	%RAX,%RCX

0x42e362 ADD	%RCX,%RDX

0x42e365 ADD	%RDX,%RAX

0x42e368 CMP	%RAX,%RDX

0x42e36b JGE	42e497

0x42e371 MOV	%RAX,%RDI

0x42e374 SUB	%RDX,%RDI

0x42e377 MOV	0x10(%R12),%R8

0x42e37c MOV	0x8(%R12),%R9

0x42e381 VXORPS	%XMM0,%XMM0,%XMM0

0x42e385 AND	$0x7,%EDI

0x42e388 JE	42e420

0x42e38e CMP	$0x1,%RDI

0x42e392 JE	42e40c

0x42e394 CMP	$0x2,%RDI

0x42e398 JE	42e3fd

0x42e39a CMP	$0x3,%RDI

0x42e39e JE	42e3ee

0x42e3a0 CMP	$0x4,%RDI

0x42e3a4 JE	42e3df

0x42e3a6 CMP	$0x5,%RDI

0x42e3aa JE	42e3d0

0x42e3ac CMP	$0x6,%RDI

0x42e3b0 JE	42e3c1

0x42e3b2 VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM1

0x42e3b8 VMOVSD	%XMM1,(%R9,%RDX,8)

0x42e3be INC	%RDX

0x42e3c1 VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM2

0x42e3c7 VMOVSD	%XMM2,(%R9,%RDX,8)

0x42e3cd INC	%RDX

0x42e3d0 VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM3

0x42e3d6 VMOVSD	%XMM3,(%R9,%RDX,8)

0x42e3dc INC	%RDX

0x42e3df VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM4

0x42e3e5 VMOVSD	%XMM4,(%R9,%RDX,8)

0x42e3eb INC	%RDX

0x42e3ee VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM5

0x42e3f4 VMOVSD	%XMM5,(%R9,%RDX,8)

0x42e3fa INC	%RDX

0x42e3fd VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM6

0x42e403 VMOVSD	%XMM6,(%R9,%RDX,8)

0x42e409 INC	%RDX

0x42e40c VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM7

0x42e412 VMOVSD	%XMM7,(%R9,%RDX,8)

0x42e418 INC	%RDX

0x42e41b CMP	%RDX,%RAX

0x42e41e JE	42e497

(99) 0x42e420 VCVTSI2SDQ	(%R8,%RDX,8),%XMM0,%XMM8

(99) 0x42e426 VCVTSI2SDQ	0x8(%R8,%RDX,8),%XMM0,%XMM9

(99) 0x42e42d VCVTSI2SDQ	0x10(%R8,%RDX,8),%XMM0,%XMM10

(99) 0x42e434 VCVTSI2SDQ	0x18(%R8,%RDX,8),%XMM0,%XMM11

(99) 0x42e43b VCVTSI2SDQ	0x20(%R8,%RDX,8),%XMM0,%XMM12

(99) 0x42e442 VCVTSI2SDQ	0x28(%R8,%RDX,8),%XMM0,%XMM13

(99) 0x42e449 VCVTSI2SDQ	0x30(%R8,%RDX,8),%XMM0,%XMM14

(99) 0x42e450 VCVTSI2SDQ	0x38(%R8,%RDX,8),%XMM0,%XMM15

(99) 0x42e457 VMOVSD	%XMM8,(%R9,%RDX,8)

(99) 0x42e45d VMOVSD	%XMM9,0x8(%R9,%RDX,8)

(99) 0x42e464 VMOVSD	%XMM10,0x10(%R9,%RDX,8)

(99) 0x42e46b VMOVSD	%XMM11,0x18(%R9,%RDX,8)

(99) 0x42e472 VMOVSD	%XMM12,0x20(%R9,%RDX,8)

(99) 0x42e479 VMOVSD	%XMM13,0x28(%R9,%RDX,8)

(99) 0x42e480 VMOVSD	%XMM14,0x30(%R9,%RDX,8)

(99) 0x42e487 VMOVSD	%XMM15,0x38(%R9,%RDX,8)

(99) 0x42e48e ADD	$0x8,%RDX

(99) 0x42e492 CMP	%RDX,%RAX

(99) 0x42e495 JNE	42e420

0x42e497 POP	%RBX

0x42e498 POP	%R12

0x42e49a POP	%RBP

0x42e49b RET

0x42e49c NOPL	(%RAX)

0x42e4a0 INC	%RAX

0x42e4a3 XOR	%EDX,%EDX

0x42e4a5 JMP	42e35e

0x42e4aa NOPW	(%RAX,%RAX,1)

Coverage (%)	Name	Source Location	Module
○97.96	gomp_thread_start	team.c:130	libgomp.so.1.0.0
○2.04	GOMP_parallel	libgomp.h:982	libgomp.so.1.0.0

Path /

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

The code analyzed by CQA in that panel excludes loops and represents 0.00% of application time for run gcc_5

Source file and lines	par_coarsen.c:2139-2142
Module	exec

The function is defined in /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139-2142.

Warnings:
Ignoring paths for analysis

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 14.00 to 6.17 cycles (2.27x speedup).

Workaround

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

Vectorization

Your function is probably not vectorized. Only 12% of vector register length is used (average across all SSE/AVX instructions). By vectorizing your function, you can lower the cost of an iteration from 14.00 to 5.00 cycles (2.80x speedup).

Details

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

Workaround

Try another compiler or update/tune your current one
Make array accesses unit-stride:
- If your function streams arrays of structures (AoS), try to use structures of arrays instead (SoA): for(i) a[i].x = b[i].x; (slow, non stride 1) => for(i) a.x[i] = b.x[i]; (fast, stride 1)

Execution units bottlenecks

Found no such bottlenecks but see expert reports for more complex bottlenecks.

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 14.00 to 13.33 cycles (1.05x speedup).

CALL instructions

Detected function call instructions.

Details

Calling (and then returning from) a function prevents many compiler optimizations (like vectorization), breaks control flow (which reduces pipeline performance) and executes extra instructions to save/restore the registers used inside it, which is very expensive (dozens of cycles). Consider to inline small functions.

omp_get_num_threads@plt: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139
omp_get_thread_num@plt: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139

Complex instructions

Detected COMPLEX INSTRUCTIONS.

Details

These instructions generate more than one micro-operation and only one of them can be decoded during a cycle and the extra micro-operations increase pressure on execution units.

IDIV: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139

Conversion instructions

Detected expensive conversion instructions.

Details

CQTO: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139
VCVTSI2SD (INT32/64 to FP64, scalar): 7 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142

Workaround

Avoid mixing data with different types. In particular, check if the type of constants is the same as array elements.

Type of elements and instruction set

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

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

The binary function does not contain any FP arithmetical operations. The binary function is loading 80 bytes. The binary function is storing 56 bytes.

General properties

nb instructions	71
nb uops	77
loop length	265
used x86 registers	11
used mmx registers	0
used xmm registers	8
used ymm registers	0
used zmm registers	0
nb stack references	0

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	14.00 cycles
front end	14.00 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11
uops	8.00	8.00	4.67	4.67	6.00	7.40	7.40	6.00	6.00	6.00	7.20	4.67
cycles	8.00	8.00	4.67	4.67	6.00	7.40	7.40	6.00	6.00	6.00	7.20	4.67

Execution ports to units layout:

P0 (256 bits): VPU, BRU, ALU, DIV/SQRT
P1 (256 bits): ALU, VPU
P2 (512 bits): load
P3 (512 bits): load
P4 (512 bits): store data
P5 (512 bits): ALU, VPU
P6: ALU, BRU
P7: store address
P8: store address
P9 (512 bits): store data
P10: ALU
P11 (512 bits): load

Cycles executing div or sqrt instructions

10.00

Cycles summary

Front-end	14.00
Dispatch	8.00
DIV/SQRT	10.00
Overall L1	14.00

Vectorization ratios

INT

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

all	12%
load	NA (no load vectorizable/vectorized instructions)
store	0%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	100%

INT+FP

all	2%
load	0%
store	0%
mul	0%
add-sub	0%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	0%
other	4%

Vector efficiency ratios

INT

all	11%
load	12%
store	NA (no store vectorizable/vectorized instructions)
mul	12%
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
other	11%

all	14%
load	NA (no load vectorizable/vectorized instructions)
store	12%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	25%

INT+FP

all	12%
load	12%
store	12%
mul	12%
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	12%
other	11%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each call to the function takes 14.00 cycles. At this rate:

2% of peak load performance is reached (5.71 out of 192.00 bytes loaded per cycle (GB/s @ 1GHz))
3% of peak store performance is reached (4.00 out of 128.00 bytes stored per cycle (GB/s @ 1GHz))

Front-end bottlenecks

Performance is limited by instruction throughput (loading/decoding program instructions to execution core) (front-end is a bottleneck).

ASM code

In the binary file, the address of the function is: 42e330

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	Latency	Recip. throughput	Vectorization
PUSH %RBP	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
MOV %RSP,%RBP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
PUSH %R12	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
MOV %RDI,%R12	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
PUSH %RBX	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
CALL 4110b0 <omp_get_num_threads@plt>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
MOV %EAX,%EBX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (6.3%)
CALL 4111f0 <omp_get_thread_num@plt>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
MOVSXD %EAX,%RCX	1	0	0.33	0	0	0	0.33	0	0	0	0	0.33	0	1	0.33	scal (6.3%)
MOV (%R12),%RAX	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
MOVSXD %EBX,%RSI	1	0	0.33	0	0	0	0.33	0	0	0	0	0.33	0	1	0.33	scal (6.3%)
CQTO	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	1	0.50	scal (12.5%)
IDIV %RSI	5	0	3	0	0	0	0	0	0	0	0	0	0	11-16	10	scal (12.5%)
CMP %RDX,%RCX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JL 42e4a0 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x170>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
IMUL %RAX,%RCX	1	0	1	0	0	0	0	0	0	0	0	0	0	3	1	scal (12.5%)
ADD %RCX,%RDX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
ADD %RDX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
CMP %RAX,%RDX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JGE 42e497 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x167>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
MOV %RAX,%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
SUB %RDX,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
MOV 0x10(%R12),%R8	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
MOV 0x8(%R12),%R9	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
VXORPS %XMM0,%XMM0,%XMM0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	vect (25.0%)
AND $0x7,%EDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1-2	0.20	scal (6.3%)
JE 42e420 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xf0>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x1,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e40c <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xdc>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x2,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3fd <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xcd>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x3,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3ee <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xbe>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x4,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3df <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xaf>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x5,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3d0 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xa0>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x6,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3c1 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x91>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM1	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM1,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM2	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM2,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM3	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM3,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM4	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM4,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM5	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM5,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM6	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM6,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM7	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM7,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
CMP %RDX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e497 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x167>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
POP %RBX	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %R12	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %RBP	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
RET	1	0.50	0	0.33	0.33	0	0	0.50	0	0	0	0	0.33	0	2.13	N/A
NOPL (%RAX)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
INC %RAX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
XOR %EDX,%EDX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
JMP 42e35e <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x2e>	1	0	0	0	0	0	0	0	0	0	0	0	0	0	2.08	N/A
NOPW (%RAX,%RAX,1)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A

The code analyzed by CQA in that panel excludes loops and represents 0.00% of application time for run gcc_5

Source file and lines	par_coarsen.c:2139-2142
Module	exec

The function is defined in /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139-2142.

Warnings:
Ignoring paths for analysis

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 14.00 to 6.17 cycles (2.27x speedup).

Workaround

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

Vectorization

Details

Workaround

Try another compiler or update/tune your current one
Make array accesses unit-stride:
- If your function streams arrays of structures (AoS), try to use structures of arrays instead (SoA): for(i) a[i].x = b[i].x; (slow, non stride 1) => for(i) a.x[i] = b.x[i]; (fast, stride 1)

Execution units bottlenecks

Found no such bottlenecks but see expert reports for more complex bottlenecks.

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 14.00 to 13.33 cycles (1.05x speedup).

CALL instructions

Detected function call instructions.

Details

omp_get_num_threads@plt: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139
omp_get_thread_num@plt: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139

Complex instructions

Detected COMPLEX INSTRUCTIONS.

Details

These instructions generate more than one micro-operation and only one of them can be decoded during a cycle and the extra micro-operations increase pressure on execution units.

IDIV: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139

Conversion instructions

Detected expensive conversion instructions.

Details

CQTO: 1 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2139
VCVTSI2SD (INT32/64 to FP64, scalar): 7 occurrences►
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142
- /home/eoseret/qaas_runs_GNR/173-927-0874/intel/AMG/build/AMG/AMG/parcsr_ls/par_coarsen.c:2142

Workaround

Avoid mixing data with different types. In particular, check if the type of constants is the same as array elements.

Type of elements and instruction set

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

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

The binary function does not contain any FP arithmetical operations. The binary function is loading 80 bytes. The binary function is storing 56 bytes.

General properties

nb instructions	71
nb uops	77
loop length	265
used x86 registers	11
used mmx registers	0
used xmm registers	8
used ymm registers	0
used zmm registers	0
nb stack references	0

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	14.00 cycles
front end	14.00 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11
uops	8.00	8.00	4.67	4.67	6.00	7.40	7.40	6.00	6.00	6.00	7.20	4.67
cycles	8.00	8.00	4.67	4.67	6.00	7.40	7.40	6.00	6.00	6.00	7.20	4.67

Execution ports to units layout:

P0 (256 bits): VPU, BRU, ALU, DIV/SQRT
P1 (256 bits): ALU, VPU
P2 (512 bits): load
P3 (512 bits): load
P4 (512 bits): store data
P5 (512 bits): ALU, VPU
P6: ALU, BRU
P7: store address
P8: store address
P9 (512 bits): store data
P10: ALU
P11 (512 bits): load

Cycles executing div or sqrt instructions

10.00

Cycles summary

Front-end	14.00
Dispatch	8.00
DIV/SQRT	10.00
Overall L1	14.00

Vectorization ratios

INT

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

all	12%
load	NA (no load vectorizable/vectorized instructions)
store	0%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	100%

INT+FP

all	2%
load	0%
store	0%
mul	0%
add-sub	0%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	0%
other	4%

Vector efficiency ratios

INT

all	11%
load	12%
store	NA (no store vectorizable/vectorized instructions)
mul	12%
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
other	11%

all	14%
load	NA (no load vectorizable/vectorized instructions)
store	12%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	NA (no add-sub vectorizable/vectorized instructions)
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	25%

INT+FP

all	12%
load	12%
store	12%
mul	12%
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	12%
other	11%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each call to the function takes 14.00 cycles. At this rate:

2% of peak load performance is reached (5.71 out of 192.00 bytes loaded per cycle (GB/s @ 1GHz))
3% of peak store performance is reached (4.00 out of 128.00 bytes stored per cycle (GB/s @ 1GHz))

Front-end bottlenecks

Performance is limited by instruction throughput (loading/decoding program instructions to execution core) (front-end is a bottleneck).

ASM code

In the binary file, the address of the function is: 42e330

Instruction	Nb FU	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11	Latency	Recip. throughput	Vectorization
PUSH %RBP	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
MOV %RSP,%RBP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
PUSH %R12	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
MOV %RDI,%R12	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
PUSH %RBX	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
CALL 4110b0 <omp_get_num_threads@plt>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
MOV %EAX,%EBX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (6.3%)
CALL 4111f0 <omp_get_thread_num@plt>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
MOVSXD %EAX,%RCX	1	0	0.33	0	0	0	0.33	0	0	0	0	0.33	0	1	0.33	scal (6.3%)
MOV (%R12),%RAX	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
MOVSXD %EBX,%RSI	1	0	0.33	0	0	0	0.33	0	0	0	0	0.33	0	1	0.33	scal (6.3%)
CQTO	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	1	0.50	scal (12.5%)
IDIV %RSI	5	0	3	0	0	0	0	0	0	0	0	0	0	11-16	10	scal (12.5%)
CMP %RDX,%RCX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JL 42e4a0 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x170>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
IMUL %RAX,%RCX	1	0	1	0	0	0	0	0	0	0	0	0	0	3	1	scal (12.5%)
ADD %RCX,%RDX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
ADD %RDX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
CMP %RAX,%RDX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JGE 42e497 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x167>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
MOV %RAX,%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
SUB %RDX,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
MOV 0x10(%R12),%R8	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
MOV 0x8(%R12),%R9	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
VXORPS %XMM0,%XMM0,%XMM0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	vect (25.0%)
AND $0x7,%EDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1-2	0.20	scal (6.3%)
JE 42e420 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xf0>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x1,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e40c <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xdc>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x2,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3fd <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xcd>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x3,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3ee <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xbe>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x4,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3df <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xaf>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x5,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3d0 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0xa0>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
CMP $0x6,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e3c1 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x91>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM1	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM1,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM2	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM2,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM3	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM3,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM4	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM4,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM5	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM5,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM6	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM6,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
VCVTSI2SDQ (%R8,%RDX,8),%XMM0,%XMM7	1	0.50	0.50	0.33	0.33	0	0	0	0	0	0	0	0.33	7	0.50	scal (12.5%)
VMOVSD %XMM7,(%R9,%RDX,8)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
INC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
CMP %RDX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JE 42e497 <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x167>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
POP %RBX	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %R12	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %RBP	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
RET	1	0.50	0	0.33	0.33	0	0	0.50	0	0	0	0	0.33	0	2.13	N/A
NOPL (%RAX)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
INC %RAX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
XOR %EDX,%EDX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
JMP 42e35e <hypre_BoomerAMGCoarsenPMIS._omp_fn.3+0x2e>	1	0	0	0	0	0	0	0	0	0	0	0	0	0	2.08	N/A
NOPW (%RAX,%RAX,1)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A

Name	Coverage (%)	Time (s)
▼hypre_BoomerAMGCoarsenPMIS._omp_fn.3–	0.02	0.01
○Loop 99 - par_coarsen.c:2142-2142 - exec	0.02	0.01

Report Configuration

Code clean check

Workaround

Vectorization

Details

Workaround

Execution units bottlenecks

Expensive FP math instructions/calls

CALL instructions

Details

Complex instructions

Details

Conversion instructions

Details

Workaround

Type of elements and instruction set

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

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

Execution units bottlenecks

Expensive FP math instructions/calls

CALL instructions

Details

Complex instructions

Details

Conversion instructions

Details

Workaround

Type of elements and instruction set

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

General properties

Front-end

Back-end

Cycles summary

Vectorization ratios

Vector efficiency ratios

Cycles and memory resources usage

Front-end bottlenecks

ASM code