[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 Martin Liška changed: What|Removed |Added See Also||https://gcc.gnu.org/bugzill ||a/show_bug.cgi?id=88753 --- Comment #14 from Martin Liška --- Thanks, I found that libzip package fails since the same revision. I'll start with that. I create new PR for that: PR88753.
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 --- Comment #13 from Romain Geissler --- Apparently the clang-tlbgen failures started with r265241. Checking if it still happens on gcc trunk with r265463 reverted.
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 --- Comment #12 from Romain Geissler --- Hi, I have tried the following script directly inside docker using the official "debian:buster" docker image, so I hope it will not require much more dependencies than what is written here. Tested with x86-64.
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 --- Comment #11 from Martin Liška --- (In reply to Romain Geissler from comment #10) > Hi, > > FYI, I bisected this revision r265463 to introduce a regression when > building the llvm toolchain. > > If you do the following: > - build gcc 9 >= r265463 (including recent revisions from late December) > - build clang 7 or clang 8 svn with this gcc 9 (it will work) > - finally with the resulting clang, build llvm's compiler-rt > > then clang itself will ICE. Before r265463 it was not the case, and > considering the nature of the fix (missed optimization) I suspect more a gcc > bug rather than a clang one. > > The exact clang failure is: > FAILED: CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o > /workdir/build/final-system/llvm-build/./bin/clang > --target=x86_64-1a-linux-gnu -DVISIBILITY_HIDDEN -O2 -mmmx -msse -msse2 > -msse3 > -I/workdir/build/final-system/llvm-temporary-static-dependencies/install/ > include > -I/workdir/build/final-system/llvm-temporary-static-dependencies/install/ > include/ncursesw -O3 -DNDEBUG-m64 -std=c11 -fPIC -fno-builtin > -fvisibility=hidden -fomit-frame-pointer -MD -MT > CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o -MF > CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o.d -o > CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o -c > /workdir/src/llvm-8.0.0/compiler-rt/lib/builtins/divtc3.c > fatal error: error in backend: Cannot select: 0x1a4b558: ch = fsqrt > 0x199e868, 0x1a46e38, FrameIndex:i64<0> > 0x1a46e38: f80,ch = CopyFromReg 0x199e868, Register:f80 %0 > 0x1a46d68: f80 = Register %0 > 0x1a4bd10: i64 = FrameIndex<0> > In function: __divtc3 > clang-8: error: clang frontend command failed with exit code 70 (use -v to > see invocation) > clang version 8.0.0 > Target: x86_64-1a-linux-gnu > Thread model: posix > InstalledDir: /workdir/build/final-system/llvm-build/./bin > clang-8: note: diagnostic msg: PLEASE submit a bug report to > https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, > and associated run script. > clang-8: note: diagnostic msg: > > > PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT: > Preprocessed source(s) and associated run script(s) are located at: > clang-8: note: diagnostic msg: /tmp/divtc3-106b93.c > clang-8: note: diagnostic msg: /tmp/divtc3-106b93.sh > clang-8: note: diagnostic msg: > > Note: step 2 and 3 (build clang then build compiler-rt with the resulting > clang) is done automatically when bootstrapping a 2-stage PGO clang using > this cmake configuration: > https://github.com/llvm-mirror/clang/blob/master/cmake/caches/PGO.cmake > > I don't know how to help more in investigating this regression. If I can do > something, please ask. > > Cheers, > Romain Thank you for the report. Can you please provide exact steps how to build the llvm/clang?
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 Romain Geissler changed: What|Removed |Added CC||romain.geissler at amadeus dot com --- Comment #10 from Romain Geissler --- Hi, FYI, I bisected this revision r265463 to introduce a regression when building the llvm toolchain. If you do the following: - build gcc 9 >= r265463 (including recent revisions from late December) - build clang 7 or clang 8 svn with this gcc 9 (it will work) - finally with the resulting clang, build llvm's compiler-rt then clang itself will ICE. Before r265463 it was not the case, and considering the nature of the fix (missed optimization) I suspect more a gcc bug rather than a clang one. The exact clang failure is: FAILED: CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o /workdir/build/final-system/llvm-build/./bin/clang --target=x86_64-1a-linux-gnu -DVISIBILITY_HIDDEN -O2 -mmmx -msse -msse2 -msse3 -I/workdir/build/final-system/llvm-temporary-static-dependencies/install/include -I/workdir/build/final-system/llvm-temporary-static-dependencies/install/include/ncursesw -O3 -DNDEBUG-m64 -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -MD -MT CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o -MF CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o.d -o CMakeFiles/clang_rt.builtins-x86_64.dir/divtc3.c.o -c /workdir/src/llvm-8.0.0/compiler-rt/lib/builtins/divtc3.c fatal error: error in backend: Cannot select: 0x1a4b558: ch = fsqrt 0x199e868, 0x1a46e38, FrameIndex:i64<0> 0x1a46e38: f80,ch = CopyFromReg 0x199e868, Register:f80 %0 0x1a46d68: f80 = Register %0 0x1a4bd10: i64 = FrameIndex<0> In function: __divtc3 clang-8: error: clang frontend command failed with exit code 70 (use -v to see invocation) clang version 8.0.0 Target: x86_64-1a-linux-gnu Thread model: posix InstalledDir: /workdir/build/final-system/llvm-build/./bin clang-8: note: diagnostic msg: PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script. clang-8: note: diagnostic msg: PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT: Preprocessed source(s) and associated run script(s) are located at: clang-8: note: diagnostic msg: /tmp/divtc3-106b93.c clang-8: note: diagnostic msg: /tmp/divtc3-106b93.sh clang-8: note: diagnostic msg: Note: step 2 and 3 (build clang then build compiler-rt with the resulting clang) is done automatically when bootstrapping a 2-stage PGO clang using this cmake configuration: https://github.com/llvm-mirror/clang/blob/master/cmake/caches/PGO.cmake I don't know how to help more in investigating this regression. If I can do something, please ask. Cheers, Romain
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 Martin Liška changed: What|Removed |Added Status|ASSIGNED|RESOLVED Resolution|--- |FIXED --- Comment #9 from Martin Liška --- Implemented.
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 --- Comment #8 from Martin Liška --- Author: marxin Date: Wed Oct 24 13:52:21 2018 New Revision: 265463 URL: https://gcc.gnu.org/viewcvs?rev=265463=gcc=rev Log: Switch conversion: support any ax + b transformation (PR tree-optimization/84436). 2018-10-24 Martin Liska PR tree-optimization/84436 * tree-switch-conversion.c (switch_conversion::contains_same_values_p): Remove. (switch_conversion::contains_linear_function_p): New. (switch_conversion::build_one_array): Support linear transformation on input. * tree-switch-conversion.h (struct switch_conversion): Add contains_linear_function_p declaration. 2018-10-24 Martin Liska PR tree-optimization/84436 * gcc.dg/tree-ssa/pr84436-1.c: New test. * gcc.dg/tree-ssa/pr84436-2.c: New test. * gcc.dg/tree-ssa/pr84436-3.c: New test. * gcc.dg/tree-ssa/pr84436-4.c: New test. * gcc.dg/tree-ssa/pr84436-5.c: New test. Added: trunk/gcc/testsuite/gcc.dg/tree-ssa/pr84436-1.c trunk/gcc/testsuite/gcc.dg/tree-ssa/pr84436-2.c trunk/gcc/testsuite/gcc.dg/tree-ssa/pr84436-3.c trunk/gcc/testsuite/gcc.dg/tree-ssa/pr84436-4.c trunk/gcc/testsuite/gcc.dg/tree-ssa/pr84436-5.c Modified: trunk/gcc/ChangeLog trunk/gcc/testsuite/ChangeLog trunk/gcc/tree-switch-conversion.c trunk/gcc/tree-switch-conversion.h
[Bug c++/84436] [8/9 Regression] Missed optimization with switch on enum constants returning the same value
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84436 Alexander Monakov changed: What|Removed |Added Summary|Missed optimization with|[8/9 Regression] Missed |switch on enum constants|optimization with switch on |returning the same value|enum constants returning ||the same value --- Comment #7 from Alexander Monakov --- The above dup was marked as regression - adjusting bug title.
