Module: Mesa Branch: main Commit: 39770c6503ac44090decd88698802bb95189bb4d URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=39770c6503ac44090decd88698802bb95189bb4d
Author: antonino <[email protected]> Date: Tue Apr 25 12:29:35 2023 +0200 zink: fix store subsitution in `lower_pv_mode_gs_store` Previously it was assumed that between the and the variable there was only one deref. To handle all cases a new function is introduced that recreates a chain of derefs. Fixes: 5a4083349f3 ("zink: add provoking vertex mode lowering") Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22678> --- src/gallium/drivers/zink/zink_compiler.c | 33 +++++++++++++++++++++++++++++--- 1 file changed, 30 insertions(+), 3 deletions(-) diff --git a/src/gallium/drivers/zink/zink_compiler.c b/src/gallium/drivers/zink/zink_compiler.c index d708ab1c879..41cda4b535f 100644 --- a/src/gallium/drivers/zink/zink_compiler.c +++ b/src/gallium/drivers/zink/zink_compiler.c @@ -426,6 +426,31 @@ lower_pv_mode_gs_ring_index(nir_builder *b, nir_imm_int(b, state->ring_size)); } +/* Given the final deref of chain of derefs this function will walk up the chain + * until it finds a var deref. + * + * It will then recreate an identical chain that ends with the provided deref. + */ +static nir_deref_instr* +replicate_derefs(nir_builder *b, nir_deref_instr *old, nir_deref_instr *new) +{ + nir_deref_instr *parent = nir_src_as_deref(old->parent); + switch(old->deref_type) { + case nir_deref_type_var: + return new; + case nir_deref_type_array: + assert(old->arr.index.is_ssa); + return nir_build_deref_array(b, replicate_derefs(b, parent, new), old->arr.index.ssa); + case nir_deref_type_struct: + return nir_build_deref_struct(b, replicate_derefs(b, parent, new), old->strct.index); + case nir_deref_type_array_wildcard: + case nir_deref_type_ptr_as_array: + case nir_deref_type_cast: + unreachable("unexpected deref type"); + } + unreachable("impossible deref type"); +} + static bool lower_pv_mode_gs_store(nir_builder *b, nir_intrinsic_instr *intrin, @@ -441,9 +466,11 @@ lower_pv_mode_gs_store(nir_builder *b, assert(intrin->src[1].is_ssa); nir_ssa_def *pos_counter = nir_load_var(b, state->pos_counter); nir_ssa_def *index = lower_pv_mode_gs_ring_index(b, state, pos_counter); - nir_store_array_var(b, state->varyings[location], - index, intrin->src[1].ssa, - nir_intrinsic_write_mask(intrin)); + nir_deref_instr *varying_deref = nir_build_deref_var(b, state->varyings[location]); + nir_deref_instr *ring_deref = nir_build_deref_array(b, varying_deref, index); + // recreate the chain of deref that lead to the store. + nir_deref_instr *new_top_deref = replicate_derefs(b, deref, ring_deref); + nir_store_deref(b, new_top_deref, intrin->src[1].ssa, nir_intrinsic_write_mask(intrin)); nir_instr_remove(&intrin->instr); return true; }
