https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43644
--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Roger Sayle <sa...@gcc.gnu.org>: https://gcc.gnu.org/g:79e1b23b91477b29deccf2cae92a7e8dd816c54a commit r14-6874-g79e1b23b91477b29deccf2cae92a7e8dd816c54a Author: Roger Sayle <ro...@nextmovesoftware.com> Date: Sun Dec 31 21:37:24 2023 +0000 i386: Tweak define_insn_and_split to fix FAIL of gcc.target/i386/pr43644-2.c This patch resolves the failure of pr43644-2.c in the testsuite, a code quality test I added back in July, that started failing as the code GCC generates for 128-bit values (and their parameter passing) has been in flux. The function: unsigned __int128 foo(unsigned __int128 x, unsigned long long y) { return x+y; } currently generates: foo: movq %rdx, %rcx movq %rdi, %rax movq %rsi, %rdx addq %rcx, %rax adcq $0, %rdx ret and with this patch, we now generate: foo: movq %rdi, %rax addq %rdx, %rax movq %rsi, %rdx adcq $0, %rdx which is optimal. 2023-12-31 Uros Bizjak <ubiz...@gmail.com> Roger Sayle <ro...@nextmovesoftware.com> gcc/ChangeLog PR target/43644 * config/i386/i386.md (*add<dwi>3_doubleword_concat_zext): Tweak order of instructions after split, to minimize number of moves. gcc/testsuite/ChangeLog PR target/43644 * gcc.target/i386/pr43644-2.c: Expect 2 movq instructions.
