From: Maxim Blinov <maxim.bli...@imgtec.com> This patch is based on and intended for the vendors/riscv/gcc-13-with-riscv-opts branch - please apply if looks OK.
Fixes the following ICEs that I'm seeing: FAIL: gcc.dg/vect/O3-pr49087.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/no-scevccp-pr86725-1.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/no-scevccp-pr86725-2.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/no-scevccp-pr86725-3.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/no-scevccp-pr86725-4.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/pr94443.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/pr94443.c -flto -ffat-lto-objects (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/slp-50.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/slp-50.c -flto -ffat-lto-objects (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/vect-cond-13.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/vect-cond-13.c -flto -ffat-lto-objects (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/vect-live-6.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.dg/vect/vect-live-6.c -flto -ffat-lto-objects (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.target/riscv/rvv/autovec/partial/live-1.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) FAIL: gcc.target/riscv/rvv/autovec/partial/live-2.c (internal compiler error: in vect_transform_loops, at tree-vectorizer.cc:1032) -- >8 -- When we create a VEC_EXPAND gimple stmt: /* SCALAR_RES = VEC_EXTRACT <VEC_LHS, LEN + BIAS - 1>. */ tree scalar_res = gimple_build (&stmts, CFN_VEC_EXTRACT, TREE_TYPE (vectype), vec_lhs_phi, last_index); Under the hood we are really just creating a GIMPLE_CALL stmt. Later on, when we `gsi_insert_seq_before` our stmts: if (stmts) { gimple_stmt_iterator exit_gsi = gsi_after_labels (exit_bb); gsi_insert_seq_before (&exit_gsi, stmts, GSI_SAME_STMT); We eventually run into tree-ssa-operands.cc:1147: operands_scanner (fn, stmt).build_ssa_operands (); Since VEC_EXPAND is *not* marked with ECF_NOVOPS, ECF_CONST, or ECF_PURE flags in internal-fn.def, when `operand_scanner::parse_ssa_operands` comes across our VEC_EXTRACT-type GIMPLE_CALL, it generates a `gimple_vop()` artificial variable. `operand_scanner::finalize_ssa_defs` then picks this up, so our final stmt goes from _73 = .VEC_EXTRACT (vect_last_9.56_71, _72); to # .MEM = VDEF <> _73 = .VEC_EXTRACT (vect_last_9.56_71, _72); But more importantly it marks us as `ssa_renaming_needed`, in tree-ssa-operands.cc:420: /* If we have a non-SSA_NAME VDEF, mark it for renaming. */ if (gimple_vdef (stmt) && TREE_CODE (gimple_vdef (stmt)) != SSA_NAME) { fn->gimple_df->rename_vops = 1; fn->gimple_df->ssa_renaming_needed = 1; } This then proceeds to crash the compiler when we are about to leave `vect_transform_loops`: if (need_ssa_update_p (cfun)) { gcc_assert (loop_vinfo->any_known_not_updated_vssa); fun->gimple_df->ssa_renaming_needed = false; todo |= TODO_update_ssa_only_virtuals; } Since, - `need_ssa_update_p (cfun)` is true (it was set when we generated a memory vdef) - `loop_vinfo->any_known_not_updated_vssa` is false As the code currently stands, creating a gimple stmt containing a VEC_EXTRACT should always generate a memory vdef, therefore we should remember to mark `loop_vinfo->any_known_not_updated_vssa` afterwards. gcc/ChangeLog: * tree-vect-loop.cc (vectorizable_live_operation): Remember to assert loop_vinfo->any_known_not_updated_vssa if we are inserting a call to VEC_EXPAND. --- gcc/tree-vect-loop.cc | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc index c8df2c88575..53c3a31d2a8 100644 --- a/gcc/tree-vect-loop.cc +++ b/gcc/tree-vect-loop.cc @@ -10155,6 +10155,11 @@ vectorizable_live_operation (vec_info *vinfo, = gimple_build (&stmts, CFN_VEC_EXTRACT, TREE_TYPE (vectype), vec_lhs_phi, last_index); + /* We've expanded SSA at this point, and since VEC_EXTRACT + will generate vops, make sure to tell GCC that we need to + update SSA. */ + loop_vinfo->any_known_not_updated_vssa = true; + /* Convert the extracted vector element to the scalar type. */ new_tree = gimple_convert (&stmts, lhs_type, scalar_res); } -- 2.34.1