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From: "schnetter at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/99912] Unnecessary / inefficient spilling of AVX2 ymm registers
Date: Tue, 06 Apr 2021 14:42:24 +0000	[thread overview]
Message-ID: <bug-99912-4-rsXMewu8OU@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-99912-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99912

--- Comment #4 from Erik Schnetter <schnetter at gmail dot com> ---
I build with the compiler options

/Users/eschnett/src/CarpetX/Cactus/view-compilers/bin/g++  -fopenmp -Wall -pipe
-g -march=skylake -std=gnu++17 -O3 -fcx-limited-range -fexcess-precision=fast
-fno-math-errno -fno-rounding-math -fno-signaling-nans
-funsafe-math-optimizations   -c -o configs/sim/build/Z4c/rhs.cxx.o
configs/sim/build/Z4c/rhs.cxx.ii

One of the kernels in question (the one I describe above) is the C++ lambda in
lines 281013 to 281119. The call to the "noinline" function ensures that the
kernel (and surrounding for loops) is compiled as a separate function, which
produces more efficient code. The function "grid.loop_int_device" contains
essentially three nested for loops, and the actual kernel is the C++ lambda in
lines 281015 to 281118.

I'll have a look at -fdump-tree-optimized.

  parent reply	other threads:[~2021-04-06 14:42 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-05  1:53 [Bug target/99912] New: " schnetter at gmail dot com
2021-04-05  1:54 ` [Bug target/99912] " schnetter at gmail dot com
2021-04-05  2:03 ` schnetter at gmail dot com
2021-04-06  8:25 ` rguenth at gcc dot gnu.org
2021-04-06 14:42 ` schnetter at gmail dot com [this message]
2021-04-06 16:33 ` schnetter at gmail dot com
2021-04-07  9:36 ` rguenth at gcc dot gnu.org
2021-04-07 16:48 ` rguenth at gcc dot gnu.org
2021-04-27 13:17 ` cvs-commit at gcc dot gnu.org
2021-04-27 13:17 ` cvs-commit at gcc dot gnu.org
2021-04-27 14:02 ` rguenth at gcc dot gnu.org
2021-04-27 16:03 ` schnetter at gmail dot com
2021-04-29  6:32 ` cvs-commit at gcc dot gnu.org

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