https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99656
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Tamar Christina <tnfch...@gcc.gnu.org>: https://gcc.gnu.org/g:c3a2bc6daaa2d278cb5f323e2df4b8c2af4198ac commit r11-7736-gc3a2bc6daaa2d278cb5f323e2df4b8c2af4198ac Author: Tamar Christina <tamar.christ...@arm.com> Date: Fri Mar 19 14:29:36 2021 +0000 slp: remove unneeded permute calculation (PR99656) The attach testcase ICEs because as you showed on the PR we have one child which is an internal with a PERM of EVENEVEN and one with TOP. The problem is while we can conceptually merge the permute itself into EVENEVEN, merging the lanes don't really make sense. That said, we no longer even require the merged lanes as we create the permutes based on the KIND directly. This patch just removes all of that code. Unfortunately it still won't vectorize with the cost model enabled due to the blend that's created combining the load and the external note: node 0x51f2ce8 (max_nunits=1, refcnt=1) note: op: VEC_PERM_EXPR note: { } note: lane permutation { 0[0] 1[1] } note: children 0x51f23e0 0x51f2578 note: node 0x51f23e0 (max_nunits=2, refcnt=1) note: op template: _16 = REALPART_EXPR <*t1_9(D)>; note: stmt 0 _16 = REALPART_EXPR <*t1_9(D)>; note: stmt 1 _16 = REALPART_EXPR <*t1_9(D)>; note: load permutation { 0 0 } note: node (external) 0x51f2578 (max_nunits=1, refcnt=1) note: { _18, _18 } which costs the cost for the load-and-split and the cost of the external splat, and the one for blending them while in reality it's just a scalar load and insert. The compiler (with the cost model disabled) generates ldr q1, [x19] dup v1.2d, v1.d[0] ldr d0, [x19, 8] fneg d0, d0 ins v1.d[1], v0.d[0] while really it should be ldp d1, d0, [x19] fneg d0, d0 ins v1.d[1], v0.d[0] but that's for another time. gcc/ChangeLog: PR tree-optimization/99656 * tree-vect-slp-patterns.c (linear_loads_p, complex_add_pattern::matches, is_eq_or_top, vect_validate_multiplication, complex_mul_pattern::matches, complex_fms_pattern::matches): Remove complex_perm_kinds_t. * tree-vectorizer.h: (complex_load_perm_t): Removed. (slp_tree_to_load_perm_map_t): Use complex_perm_kinds_t instead of complex_load_perm_t. gcc/testsuite/ChangeLog: PR tree-optimization/99656 * gfortran.dg/vect/pr99656.f90: New test.
