performance: 0.959
graphic: 0.587
device: 0.569
vnc: 0.526
kernel: 0.461
network: 0.423
VMM: 0.412
risc-v: 0.407
semantic: 0.395
socket: 0.363
ppc: 0.359
architecture: 0.356
x86: 0.327
boot: 0.320
files: 0.300
i386: 0.265
permissions: 0.261
KVM: 0.249
arm: 0.246
hypervisor: 0.236
TCG: 0.221
PID: 0.218
peripherals: 0.211
mistranslation: 0.200
assembly: 0.167
virtual: 0.161
register: 0.154
debug: 0.145
user-level: 0.108

Performance improvement when using "QEMU_FLATTEN" with softfloat type conversions

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.







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.


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