OV - exec - Function main.omp

	Function: main.omp_outlined.14	Module: exec	Source: stream.c:271-275	Coverage (incl. loops): 1.50% \| (excl. loops): 0.00%

/beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c: 271 - 275

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

271: #pragma omp parallel for

272:     for (j=0; j<STREAM_ARRAY_SIZE; j++) {

273: 	    a[j] = 1.0;

274: 	    b[j] = 2.0;

275: 	    c[j] = 0.0;

0x202fd0 PUSH	%RBP

0x202fd1 MOV	%RSP,%RBP

0x202fd4 PUSH	%R15

0x202fd6 PUSH	%R14

0x202fd8 PUSH	%R13

0x202fda PUSH	%R12

0x202fdc PUSH	%RBX

0x202fdd SUB	$0x28,%RSP

0x202fe1 MOVQ	$0,-0x40(%RBP)

0x202fe9 MOVQ	$0x3344ffff,-0x30(%RBP)

0x202ff1 LEA	0x33f8(%RIP),%RBX

0x202ff8 MOVQ	$0x1,-0x48(%RBP)

0x203000 MOVL	$0,-0x34(%RBP)

0x203007 MOV	(%RDI),%R14D

0x20300a SUB	$0x8,%RSP

0x20300e LEA	-0x48(%RBP),%RAX

0x203012 MOV	$0x10b8,%RDI

0x20301c ADD	%RBX,%RDI

0x20301f LEA	-0x34(%RBP),%RCX

0x203023 LEA	-0x40(%RBP),%R8

0x203027 LEA	-0x30(%RBP),%R9

0x20302b MOV	%R14D,%ESI

0x20302e MOV	$0x22,%EDX

0x203033 PUSH	$0x1

0x203035 PUSH	$0x1

0x203037 PUSH	%RAX

0x203038 CALL	2041f0 <@plt_start@+0x80>

0x20303d ADD	$0x20,%RSP

0x203041 MOV	-0x30(%RBP),%RAX

0x203045 CMP	$0x3344ffff,%RAX

0x20304b MOV	$0x3344ffff,%R15D

0x203051 CMOVL	%RAX,%R15

0x203055 MOV	%R15,-0x30(%RBP)

0x203059 MOV	-0x40(%RBP),%R13

0x20305d CMP	%R15,%R13

0x203060 JG	203182

0x203066 MOV	$0x334501190,%RAX

0x203070 ADD	%RBX,%RAX

0x203073 LEA	(%RAX,%R13,8),%RDI

0x203077 MOV	%R15,%R12

0x20307a SUB	%R13,%R12

0x20307d LEA	0x8(,%R12,8),%RDX

0x203085 INC	%R12

0x203088 XOR	%ESI,%ESI

0x20308a CALL	204200 <@plt_start@+0x90>

0x20308f MOV	$0x1190,%RAX

0x203099 MOV	$0x19a281190,%RCX

0x2030a3 CMP	$0x8,%R12

0x2030a7 JAE	2030b1

0x2030a9 MOV	%R13,%RDX

0x2030ac JMP	203144

0x2030b1 MOV	%R12,%RSI

0x2030b4 AND	$-0x8,%RSI

0x2030b8 LEA	(%R13,%RSI,1),%RDX

0x2030bd LEA	(%RBX,%RAX,1),%RDI

0x2030c1 LEA	0x30(%RDI,%R13,8),%RDI

0x2030c6 LEA	(%RBX,%RCX,1),%R8

0x2030ca LEA	0x30(%R8,%R13,8),%R8

0x2030cf XOR	%R9D,%R9D

0x2030d2 MOV	$-0x5c20,%R10

0x2030dc VMOVDDUP	(%RBX,%R10,1),%XMM0

0x2030e2 MOV	$-0x5c48,%R10

0x2030ec VMOVDDUP	(%RBX,%R10,1),%XMM1

0x2030f2 NOPW	%CS:(%RAX,%RAX,1)

(2) 0x203100 VMOVUPS	%XMM0,-0x30(%RDI,%R9,8)

(2) 0x203107 VMOVUPS	%XMM0,-0x20(%RDI,%R9,8)

(2) 0x20310e VMOVUPS	%XMM0,-0x10(%RDI,%R9,8)

(2) 0x203115 VMOVUPS	%XMM0,(%RDI,%R9,8)

(2) 0x20311b VMOVUPS	%XMM1,-0x30(%R8,%R9,8)

(2) 0x203122 VMOVUPS	%XMM1,-0x20(%R8,%R9,8)

(2) 0x203129 VMOVUPS	%XMM1,-0x10(%R8,%R9,8)

(2) 0x203130 VMOVUPS	%XMM1,(%R8,%R9,8)

(2) 0x203136 ADD	$0x8,%R9

(2) 0x20313a CMP	%R9,%RSI

(2) 0x20313d JNE	203100

0x20313f CMP	%RSI,%R12

0x203142 JE	203182

0x203144 DEC	%RDX

0x203147 ADD	%RBX,%RAX

0x20314a MOV	$0x3ff0000000000000,%RSI

0x203154 ADD	%RBX,%RCX

0x203157 MOV	$0x4000000000000000,%RDI

0x203161 NOPW	%CS:(%RAX,%RAX,1)

(3) 0x203170 MOV	%RSI,0x8(%RAX,%RDX,8)

(3) 0x203175 MOV	%RDI,0x8(%RCX,%RDX,8)

(3) 0x20317a INC	%RDX

(3) 0x20317d CMP	%R15,%RDX

(3) 0x203180 JL	203170

0x203182 MOV	$0x10d0,%RAX

0x20318c ADD	%RAX,%RBX

0x20318f MOV	%RBX,%RDI

0x203192 MOV	%R14D,%ESI

0x203195 CALL	204210 <@plt_start@+0xa0>

0x20319a ADD	$0x28,%RSP

0x20319e POP	%RBX

0x20319f POP	%R12

0x2031a1 POP	%R13

0x2031a3 POP	%R14

0x2031a5 POP	%R15

0x2031a7 POP	%RBP

0x2031a8 RET

0x2031a9 NOPL	(%RAX)

Coverage (%)	Name	Source Location	Module
►99.21+	__kmp_invoke_microtask		libomp.so
○	__kmp_invoke_task_func		libomp.so

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 /

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 aocc_9

Source file and lines	stream.c:271-275
Module	exec

The function is defined in /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:271-275.

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 14.83 to 1.50 cycles (9.89x speedup).

Workaround

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

Vectorization

Your function is not vectorized. Only 9% 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 14.83 to 1.01 cycles (14.64x speedup).

Details

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

No data for this section

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.

unknown: 3 occurrences►
- /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:271
- /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:275
- /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:271

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 36 bytes. The binary function is storing 36 bytes.

General properties

nb instructions	86
nb uops	89
loop length	399
used x86 registers	15
used mmx registers	0
used xmm registers	2
used ymm registers	0
used zmm registers	0
nb stack references	4

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	14.83 cycles
front end	14.83 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11
uops	5.90	5.80	4.00	4.00	8.50	5.80	5.70	8.50	8.50	8.50	5.80	4.00
cycles	5.90	6.40	4.00	4.00	8.50	5.80	5.70	8.50	8.50	8.50	5.80	4.00

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

Cycles summary

Front-end	14.83
Dispatch	8.50
Overall L1	14.83

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	0%
store	NA (no store vectorizable/vectorized instructions)
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	NA (no other vectorizable/vectorized instructions)

INT+FP

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

Vector efficiency ratios

INT

all	9%
load	6%
store	7%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
other	10%

all	12%
load	12%
store	NA (no store vectorizable/vectorized instructions)
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	NA (no other vectorizable/vectorized instructions)

INT+FP

all	9%
load	10%
store	7%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	10%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each call to the function takes 14.83 cycles. At this rate:

1% of peak load performance is reached (2.43 out of 192.00 bytes loaded per cycle (GB/s @ 1GHz))
1% of peak store performance is reached (2.43 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). By removing all these bottlenecks, you can lower the cost of an iteration from 14.83 to 8.50 cycles (1.75x speedup).

ASM code

In the binary file, the address of the function is: 202fd0

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	N/A
PUSH %R15	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH %R14	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH %R13	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
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
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
SUB $0x28,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOVQ $0,-0x40(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
MOVQ $0x3344ffff,-0x30(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
LEA 0x33f8(%RIP),%RBX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOVQ $0x1,-0x48(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
MOVL $0,-0x34(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
MOV (%RDI),%R14D	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	scal (6.3%)
SUB $0x8,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
LEA -0x48(%RBP),%RAX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV $0x10b8,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RBX,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
LEA -0x34(%RBP),%RCX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA -0x40(%RBP),%R8	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA -0x30(%RBP),%R9	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV %R14D,%ESI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOV $0x22,%EDX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (6.3%)
PUSH $0x1	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH $0x1	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH %RAX	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
CALL 2041f0 <@plt_start@+0x80>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
ADD $0x20,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOV -0x30(%RBP),%RAX	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
CMP $0x3344ffff,%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%)
MOV $0x3344ffff,%R15D	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (6.3%)
CMOVL %RAX,%R15	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	1	0.50	scal (12.5%)
MOV %R15,-0x30(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
MOV -0x40(%RBP),%R13	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
CMP %R15,%R13	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JG 203182 <main.omp_outlined.14+0x1b2>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
MOV $0x334501190,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RBX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
LEA (%RAX,%R13,8),%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV %R15,%R12	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
SUB %R13,%R12	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
LEA 0x8(,%R12,8),%RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
INC %R12	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
XOR %ESI,%ESI	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
CALL 204200 <@plt_start@+0x90>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
MOV $0x1190,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
MOV $0x19a281190,%RCX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
CMP $0x8,%R12	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JAE 2030b1 <main.omp_outlined.14+0xe1>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
MOV %R13,%RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
JMP 203144 <main.omp_outlined.14+0x174>	1	0	0	0	0	0	0	0	0	0	0	0	0	0	2.08	N/A
MOV %R12,%RSI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
AND $-0x8,%RSI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1-2	0.20	N/A
LEA (%R13,%RSI,1),%RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA (%RBX,%RAX,1),%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA 0x30(%RDI,%R13,8),%RDI	1	0	1	0	0	0	0	0	0	0	0	0	0	3	1	N/A
LEA (%RBX,%RCX,1),%R8	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA 0x30(%R8,%R13,8),%R8	1	0	1	0	0	0	0	0	0	0	0	0	0	3	1	N/A
XOR %R9D,%R9D	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	scal (6.3%)
MOV $-0x5c20,%R10	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
VMOVDDUP (%RBX,%R10,1),%XMM0	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	scal (12.5%)
MOV $-0x5c48,%R10	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
VMOVDDUP (%RBX,%R10,1),%XMM1	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	scal (12.5%)
NOPW %CS:(%RAX,%RAX,1)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
CMP %RSI,%R12	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 203182 <main.omp_outlined.14+0x1b2>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
DEC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
ADD %RBX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
MOV $0x3ff0000000000000,%RSI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RBX,%RCX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
MOV $0x4000000000000000,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
NOPW %CS:(%RAX,%RAX,1)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV $0x10d0,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RAX,%RBX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
MOV %RBX,%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOV %R14D,%ESI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
CALL 204210 <@plt_start@+0xa0>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
ADD $0x28,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	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 %R13	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %R14	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %R15	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

The code analyzed by CQA in that panel excludes loops and represents 0.00% of application time for run aocc_9

Source file and lines	stream.c:271-275
Module	exec

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 14.83 to 1.50 cycles (9.89x 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.

No data for this section

CALL instructions

Detected function call instructions.

Details

unknown: 3 occurrences►
- /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:271
- /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:275
- /beegfs/hackathon/users/eoseret/qaas_runs_test/isix04.benchmarkcenter.megware.com/177-373-8011/stream-scale/build/stream-scale/src/stream.c:271

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 36 bytes. The binary function is storing 36 bytes.

General properties

nb instructions	86
nb uops	89
loop length	399
used x86 registers	15
used mmx registers	0
used xmm registers	2
used ymm registers	0
used zmm registers	0
nb stack references	4

Front-end

MACRO FUSION NOT POSSIBLE FIT IN UOP CACHE

micro-operation queue	14.83 cycles
front end	14.83 cycles

Back-end

	P0	P1	P2	P3	P4	P5	P6	P7	P8	P9	P10	P11
uops	5.90	5.80	4.00	4.00	8.50	5.80	5.70	8.50	8.50	8.50	5.80	4.00
cycles	5.90	6.40	4.00	4.00	8.50	5.80	5.70	8.50	8.50	8.50	5.80	4.00

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

Cycles summary

Front-end	14.83
Dispatch	8.50
Overall L1	14.83

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	0%
store	NA (no store vectorizable/vectorized instructions)
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	NA (no other vectorizable/vectorized instructions)

INT+FP

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

Vector efficiency ratios

INT

all	9%
load	6%
store	7%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
other	10%

all	12%
load	12%
store	NA (no store vectorizable/vectorized instructions)
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	NA (no other vectorizable/vectorized instructions)

INT+FP

all	9%
load	10%
store	7%
mul	NA (no mul vectorizable/vectorized instructions)
add-sub	12%
fma	NA (no fma vectorizable/vectorized instructions)
div/sqrt	NA (no div/sqrt vectorizable/vectorized instructions)
other	10%

Cycles and memory resources usage

Assuming all data fit into the L1 cache, each call to the function takes 14.83 cycles. At this rate:

1% of peak load performance is reached (2.43 out of 192.00 bytes loaded per cycle (GB/s @ 1GHz))
1% of peak store performance is reached (2.43 out of 128.00 bytes stored per cycle (GB/s @ 1GHz))

Front-end bottlenecks

ASM code

In the binary file, the address of the function is: 202fd0

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	N/A
PUSH %R15	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH %R14	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH %R13	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
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
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
SUB $0x28,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOVQ $0,-0x40(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
MOVQ $0x3344ffff,-0x30(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
LEA 0x33f8(%RIP),%RBX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOVQ $0x1,-0x48(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
MOVL $0,-0x34(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (6.3%)
MOV (%RDI),%R14D	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	scal (6.3%)
SUB $0x8,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
LEA -0x48(%RBP),%RAX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV $0x10b8,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RBX,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
LEA -0x34(%RBP),%RCX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA -0x40(%RBP),%R8	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA -0x30(%RBP),%R9	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV %R14D,%ESI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOV $0x22,%EDX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (6.3%)
PUSH $0x1	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH $0x1	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
PUSH %RAX	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	5-12	0.50	N/A
CALL 2041f0 <@plt_start@+0x80>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
ADD $0x20,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOV -0x30(%RBP),%RAX	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
CMP $0x3344ffff,%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%)
MOV $0x3344ffff,%R15D	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (6.3%)
CMOVL %RAX,%R15	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	1	0.50	scal (12.5%)
MOV %R15,-0x30(%RBP)	1	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	1	0.50	scal (12.5%)
MOV -0x40(%RBP),%R13	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	N/A
CMP %R15,%R13	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JG 203182 <main.omp_outlined.14+0x1b2>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
MOV $0x334501190,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RBX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
LEA (%RAX,%R13,8),%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV %R15,%R12	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
SUB %R13,%R12	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
LEA 0x8(,%R12,8),%RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
INC %R12	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
XOR %ESI,%ESI	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
CALL 204200 <@plt_start@+0x90>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
MOV $0x1190,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
MOV $0x19a281190,%RCX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
CMP $0x8,%R12	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	scal (12.5%)
JAE 2030b1 <main.omp_outlined.14+0xe1>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
MOV %R13,%RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
JMP 203144 <main.omp_outlined.14+0x174>	1	0	0	0	0	0	0	0	0	0	0	0	0	0	2.08	N/A
MOV %R12,%RSI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
AND $-0x8,%RSI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1-2	0.20	N/A
LEA (%R13,%RSI,1),%RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA (%RBX,%RAX,1),%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA 0x30(%RDI,%R13,8),%RDI	1	0	1	0	0	0	0	0	0	0	0	0	0	3	1	N/A
LEA (%RBX,%RCX,1),%R8	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
LEA 0x30(%R8,%R13,8),%R8	1	0	1	0	0	0	0	0	0	0	0	0	0	3	1	N/A
XOR %R9D,%R9D	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	scal (6.3%)
MOV $-0x5c20,%R10	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
VMOVDDUP (%RBX,%R10,1),%XMM0	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	scal (12.5%)
MOV $-0x5c48,%R10	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
VMOVDDUP (%RBX,%R10,1),%XMM1	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1	0.33	scal (12.5%)
NOPW %CS:(%RAX,%RAX,1)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
CMP %RSI,%R12	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 203182 <main.omp_outlined.14+0x1b2>	1	0.50	0	0	0	0	0	0.50	0	0	0	0	0	0	0.50	N/A
DEC %RDX	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	scal (12.5%)
ADD %RBX,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
MOV $0x3ff0000000000000,%RSI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RBX,%RCX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
MOV $0x4000000000000000,%RDI	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
NOPW %CS:(%RAX,%RAX,1)	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0.17	N/A
MOV $0x10d0,%RAX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.28	N/A
ADD %RAX,%RBX	1	0.20	0.20	0	0	0	0.20	0.20	0	0	0	0.20	0	1	0.20	N/A
MOV %RBX,%RDI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
MOV %R14D,%ESI	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	N/A
CALL 204210 <@plt_start@+0xa0>	2	0	0	0	0	0.50	0	0	0.50	0.50	0.50	0	0	0	1	N/A
ADD $0x28,%RSP	1	0	0	0	0	0	0	0	0	0	0	0	0	1	0.17	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 %R13	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %R14	1	0	0	0.33	0.33	0	0	0	0	0	0	0	0.33	1-6	0.33	N/A
POP %R15	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

Name	Coverage (%)	Time (s)
▼main.omp_outlined.14–	1.50	0.05
○Loop 2 - stream.c:273-274 - exec	1.50	0.04
○Loop 3 - stream.c:272-274 - exec	0.00	0.00

Report Configuration

Code clean check

Workaround

Vectorization

Details

Workaround

Execution units bottlenecks

CALL instructions

Details

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

CALL instructions

Details

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