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* [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
@ 2020-08-18 18:36 Ahmed Karaman
  2020-08-18 18:37 ` [Bug 1892081] " Ahmed Karaman
                   ` (5 more replies)
  0 siblings, 6 replies; 7+ messages in thread
From: Ahmed Karaman @ 2020-08-18 18:36 UTC (permalink / raw)
  To: qemu-devel

Public bug reported:

Attached below is a matrix multiplication program for double data
types. The program performs the casting operation "(double)rand()"
when generating random numbers.

This operation calls the integer to float softfloat conversion
function "int32_to_float_64".

Adding the "QEMU_FLATTEN" attribute to the function definition
decreases the instructions per call of the function by about 63%.

Attached are before and after performance screenshots from
KCachegrind.

** Affects: qemu
     Importance: Undecided
         Status: New

** Attachment added: "matmult_double.c"
   https://bugs.launchpad.net/bugs/1892081/+attachment/5402577/+files/matmult_double.c

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https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  New

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug 1892081] Re: Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
  2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
@ 2020-08-18 18:37 ` Ahmed Karaman
  2020-08-18 18:37 ` Ahmed Karaman
                   ` (4 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: Ahmed Karaman @ 2020-08-18 18:37 UTC (permalink / raw)
  To: qemu-devel

** Attachment added: "before.png"
   https://bugs.launchpad.net/qemu/+bug/1892081/+attachment/5402578/+files/before.png

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https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  New

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug 1892081] Re: Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
  2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
  2020-08-18 18:37 ` [Bug 1892081] " Ahmed Karaman
@ 2020-08-18 18:37 ` Ahmed Karaman
  2020-10-18 20:26 ` Richard Henderson
                   ` (3 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: Ahmed Karaman @ 2020-08-18 18:37 UTC (permalink / raw)
  To: qemu-devel

** Attachment added: "after.png"
   https://bugs.launchpad.net/qemu/+bug/1892081/+attachment/5402579/+files/after.png

-- 
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https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  New

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug 1892081] Re: Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
  2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
  2020-08-18 18:37 ` [Bug 1892081] " Ahmed Karaman
  2020-08-18 18:37 ` Ahmed Karaman
@ 2020-10-18 20:26 ` Richard Henderson
  2021-05-04 19:39 ` Thomas Huth
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 7+ messages in thread
From: Richard Henderson @ 2020-10-18 20:26 UTC (permalink / raw)
  To: qemu-devel

Confirmed, although "65% decrease" is on 0.44% of the total
execution for this test case, so the decrease isn't actually
noticeable.

Nevertheless, it's a simple enough change.

** Changed in: qemu
       Status: New => In Progress

** Changed in: qemu
     Assignee: (unassigned) => Richard Henderson (rth)

-- 
You received this bug notification because you are a member of qemu-
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https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  In Progress

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug 1892081] Re: Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
  2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
                   ` (2 preceding siblings ...)
  2020-10-18 20:26 ` Richard Henderson
@ 2021-05-04 19:39 ` Thomas Huth
  2021-06-23 17:32 ` Richard Henderson
  2021-08-25  7:17 ` Thomas Huth
  5 siblings, 0 replies; 7+ messages in thread
From: Thomas Huth @ 2021-05-04 19:39 UTC (permalink / raw)
  To: qemu-devel

This is an automated cleanup. This bug report has been moved to QEMU's
new bug tracker on gitlab.com and thus gets marked as 'expired' now.
Please continue with the discussion here:

 https://gitlab.com/qemu-project/qemu/-/issues/134


** Changed in: qemu
       Status: In Progress => Expired

** Changed in: qemu
     Assignee: Richard Henderson (rth) => (unassigned)

** Bug watch added: gitlab.com/qemu-project/qemu/-/issues #134
   https://gitlab.com/qemu-project/qemu/-/issues/134

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https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  Expired

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug 1892081] Re: Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
  2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
                   ` (3 preceding siblings ...)
  2021-05-04 19:39 ` Thomas Huth
@ 2021-06-23 17:32 ` Richard Henderson
  2021-08-25  7:17 ` Thomas Huth
  5 siblings, 0 replies; 7+ messages in thread
From: Richard Henderson @ 2021-06-23 17:32 UTC (permalink / raw)
  To: qemu-devel

** Changed in: qemu
       Status: Expired => Fix Committed

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devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  Fix Committed

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [Bug 1892081] Re: Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions
  2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
                   ` (4 preceding siblings ...)
  2021-06-23 17:32 ` Richard Henderson
@ 2021-08-25  7:17 ` Thomas Huth
  5 siblings, 0 replies; 7+ messages in thread
From: Thomas Huth @ 2021-08-25  7:17 UTC (permalink / raw)
  To: qemu-devel

** Changed in: qemu
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1892081

Title:
  Performance improvement when using "QEMU_FLATTEN" with softfloat type
  conversions

Status in QEMU:
  Fix Released

Bug description:
  Attached below is a matrix multiplication program for double data
  types. The program performs the casting operation "(double)rand()"
  when generating random numbers.

  This operation calls the integer to float softfloat conversion
  function "int32_to_float_64".

  Adding the "QEMU_FLATTEN" attribute to the function definition
  decreases the instructions per call of the function by about 63%.

  Attached are before and after performance screenshots from
  KCachegrind.

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1892081/+subscriptions



^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2021-08-25  7:31 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-18 18:36 [Bug 1892081] [NEW] Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions Ahmed Karaman
2020-08-18 18:37 ` [Bug 1892081] " Ahmed Karaman
2020-08-18 18:37 ` Ahmed Karaman
2020-10-18 20:26 ` Richard Henderson
2021-05-04 19:39 ` Thomas Huth
2021-06-23 17:32 ` Richard Henderson
2021-08-25  7:17 ` Thomas Huth

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