[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 Jiu Fu Guo changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|--- |FIXED --- Comment #8 from Jiu Fu Guo --- Fixed now.
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 --- Comment #7 from CVS Commits --- The master branch has been updated by Jiu Fu Guo : https://gcc.gnu.org/g:1060cd2ad00b5174f4f8ef8ca3d8c283e321ffca commit r13-4803-g1060cd2ad00b5174f4f8ef8ca3d8c283e321ffca Author: Jiufu Guo Date: Tue Dec 20 11:43:57 2022 +0800 rs6000: Optimize cmp on rotated 16bits constant Hi, When checking eq/ne with a constant which has only 16bits, it can be optimized to check the rotated data. By this, the constant building is optimized. As the example in PR103743: For "in == 0x8000LL", this patch generates: rotldi 3,3,1 ; cmpldi 0,3,1 instead of: li 9,-1 ; rldicr 9,9,0,0 ; cmpd 0,3,9 Compare with previous version: https://gcc.gnu.org/pipermail/gcc-patches/2022-August/600475.html. This patch refactor the code according to review comments. e.g. updating function names/comments/code. This patch pass bootstrap and regtest on ppc64 and ppc64le. Is it ok for trunk? Thanks for comments! BR, Jeff(Jiufu) PR target/103743 gcc/ChangeLog: * config/rs6000/rs6000-protos.h (can_be_rotated_to_lowbits): New. (can_be_rotated_to_positive_16bits): New. (can_be_rotated_to_negative_15bits): New. * config/rs6000/rs6000.cc (can_be_rotated_to_lowbits): New definition. (can_be_rotated_to_positive_16bits): New definition. (can_be_rotated_to_negative_15bits): New definition. * config/rs6000/rs6000.md (*rotate_on_cmpdi): New define_insn_and_split. (eqne): Move earlier. gcc/testsuite/ChangeLog: * gcc.target/powerpc/pr103743.c: New test. * gcc.target/powerpc/pr103743_1.c: New test.
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 --- Comment #6 from Jiu Fu Guo --- Drafted a patch: https://gcc.gnu.org/pipermail/gcc-patches/2022-May/594702.html
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 --- Comment #5 from Jiu Fu Guo --- It would be also ok for the constant that only has 16bits in the middle: e.g. 0x09876000ULL, we can rotate the constant to 0x9876.
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 Jiu Fu Guo changed: What|Removed |Added Assignee|unassigned at gcc dot gnu.org |guojiufu at gcc dot gnu.org --- Comment #4 from Jiu Fu Guo --- rot(a)==rot(b_)==> a==rot(b')
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 Jiu Fu Guo changed: What|Removed |Added CC||guojiufu at gcc dot gnu.org --- Comment #3 from Jiu Fu Guo --- For "in == 0x8000LL", it would be also ok with: rotldi %r9,%r3,16 cmpldi %cr0,%r9,32768 And it would be similar for "in == 0x8000LL" (highest bit and low48bits are all 1) rotldi %r9,%r3,16 cmpdi %cr0,%r9,-32768
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 --- Comment #2 from pthaugen at gcc dot gnu.org --- (In reply to Peter Bergner from comment #1) > Pat, does the patch from Alan you're working to get committed help with this > test case? No, it just loads the constant slightly different: li 9,1 rotldi 9,9,63 cmpd 0,3,9
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 Peter Bergner changed: What|Removed |Added CC||pthaugen at gcc dot gnu.org --- Comment #1 from Peter Bergner --- Pat, does the patch from Alan you're working to get committed help with this test case?
[Bug target/103743] PPC: Inefficient equality compare for large 64-bit constants having only 16-bit relevant bits in high part
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103743 Andrew Pinski changed: What|Removed |Added Severity|normal |enhancement
