https://gcc.gnu.org/bugzilla/show_bug.cgi?id=7061
--- Comment #11 from CVS 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:64d4f27a0ce47e97867512bda7fa5683acf8a134 commit r13-1282-g64d4f27a0ce47e97867512bda7fa5683acf8a134 Author: Roger Sayle <ro...@nextmovesoftware.com> Date: Mon Jun 27 07:47:40 2022 +0100 Implement __imag__ of float _Complex using shufps on x86_64. This patch is a follow-up improvement to my recent patch for PR rtl-optimization/7061. That patch added the test case gcc.target/i386/pr7061-2.c: float im(float _Complex a) { return __imag__ a; } For which GCC on x86_64 currently generates: movq %xmm0, %rax shrq $32, %rax movd %eax, %xmm0 ret but with this patch we now generate (the same as LLVM): shufps $85, %xmm0, %xmm0 ret This is achieved by providing a define_insn_and_split that allows truncated lshiftrt:DI by 32 to be performed on either SSE or general regs, where if the register allocator prefers to use SSE, we split to a shufps_v4si, or if not, we use a regular shrq. 2022-06-27 Roger Sayle <ro...@nextmovesoftware.com> gcc/ChangeLog PR rtl-optimization/7061 * config/i386/i386.md (*highpartdisi2): New define_insn_and_split. gcc/testsuite/ChangeLog PR rtl-optimization/7061 * gcc.target/i386/pr7061-2.c: Update to look for shufps.
