[Bug c++/94957] New: Compilation slowww for simple code with -O1/2/3 and -g in GCC 8 and 9

Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- code: - class MyObject { public: MyObject() {} }; class MyClassSlow

[Bug target/93535] New: slow float/double simple constant folding with -Ofast

Component: target Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Created attachment 47763 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47763&action=edit testcase slow float/double simple constant folding with

[Bug tree-optimization/93521] New: 40% slower in O2 than O1 (tree-pre)

-optimization Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Created attachment 47747 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47747&action=edit testcase The attached heap sort is ~40% slower in O2 than O1 (sl

[Bug target/93037] New: Slow 'while' loop unrolling

nt: target Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Created attachment 47538 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47538&action=edit Adobe_C++Benchmarks Compile and run 'loop unroll test' in

[Bug c++/91895] Compile the code with -O1 or -O2 is slower than with -O3 and -Os

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91895 --- Comment #1 from hehaochen at hotmail dot com --- I think maybe the problem has already been fixed since gcc 5?

[Bug c++/91895] New: Compile the code with -O1 or -O2 is slower than with -O3 and -Os

Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Compiling the following code in gcc (GCC) 4.6.4: # time gcc -O1 test.cpp real0m18.180s user0m16.368s sys 0m1.812s

[Bug c++/91875] Performance drop with mt19937 with -O2/-O3/-Ofast compared to -O1

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91875 --- Comment #1 from hehaochen at hotmail dot com --- All the experiments are run on gcc-docker(https://hub.docker.com/_/gcc?tab=description) on CentOS Linux release 7.6.1810 Core.

[Bug c++/91875] New: Performance drop with mt19937 with -O2/-O3/-Ofast compared to -O1

Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Compile the following code and run: > g++ -O0/-O1/-O2/-O3/-Ofast test.cpp > .

[Bug c/91852] New: Compile the code with -O0 is slower than with -O1/-O2/-O3

Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Compile the following code with -O0 is slower than with -O1/-O2/-O3 : -O1 applies some optimization on execution time and binary size, I

[Bug c/91817] New: compile with -O3 is more-than-expectedly slower than -O2

Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: hehaochen at hotmail dot com Target Milestone: --- Created attachment 46898 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=46898&action=edit this test case is from gcc-45364 ###