--- /dev/null
+/*
+ * Copyright © 2020 Microsoft Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include "nir.h"
+#include "nir_builder.h"
+#include "nir_builder_opcodes.h"
+
+#include "util/u_math.h"
+
+static bool
+lower_printf_instr(nir_builder *b, nir_instr *instr, void *_options)
+{
+ const nir_lower_printf_options *options = _options;
+ if (instr->type != nir_instr_type_intrinsic)
+ return false;
+
+ nir_intrinsic_instr *prntf = nir_instr_as_intrinsic(instr);
+ if (prntf->intrinsic != nir_intrinsic_printf)
+ return false;
+
+ nir_ssa_def *fmt_str_id = prntf->src[0].ssa;
+ nir_deref_instr *args = nir_src_as_deref(prntf->src[1]);
+ assert(args->deref_type == nir_deref_type_var);
+
+ const unsigned ptr_bit_size = nir_get_ptr_bitsize(b->shader);
+
+ /* Atomic add a buffer size counter to determine where to write. If
+ * overflowed, return -1, otherwise, store the arguments and return 0.
+ */
+ b->cursor = nir_before_instr(&prntf->instr);
+ nir_ssa_def *buffer_addr = nir_load_printf_buffer_address(b, ptr_bit_size);
+ nir_deref_instr *buffer =
+ nir_build_deref_cast(b, buffer_addr, nir_var_mem_global,
+ glsl_array_type(glsl_uint8_t_type(), 0, 4), 0);
+
+ /* Align the struct size to 4 */
+ assert(glsl_type_is_struct_or_ifc(args->type));
+ int args_size = align(glsl_get_cl_size(args->type), 4);
+ assert(fmt_str_id->bit_size == 32);
+ int fmt_str_id_size = 4;
+
+ /* Increment the counter at the beginning of the buffer */
+ const unsigned counter_size = 4;
+ nir_deref_instr *counter = nir_build_deref_array_imm(b, buffer, 0);
+ counter = nir_build_deref_cast(b, &counter->dest.ssa,
+ nir_var_mem_global,
+ glsl_uint_type(), 0);
+ counter->cast.align_mul = 4;
+ nir_ssa_def *offset =
+ nir_deref_atomic_add(b, 32, &counter->dest.ssa,
+ nir_imm_int(b, fmt_str_id_size + args_size));
+
+ /* Check if we're still in-bounds */
+ const unsigned default_buffer_size = 1024 * 1024;
+ unsigned buffer_size = (options && options->max_buffer_size) ?
+ options->max_buffer_size : default_buffer_size;
+ int max_valid_offset =
+ buffer_size - args_size - fmt_str_id_size - counter_size;
+ nir_push_if(b, nir_ilt(b, offset, nir_imm_int(b, max_valid_offset)));
+
+ nir_ssa_def *printf_succ_val = nir_imm_int(b, 0);
+
+ /* Write the format string ID */
+ nir_ssa_def *fmt_str_id_offset =
+ nir_i2i(b, offset, ptr_bit_size);
+ nir_deref_instr *fmt_str_id_deref =
+ nir_build_deref_array(b, buffer, fmt_str_id_offset);
+ fmt_str_id_deref = nir_build_deref_cast(b, &fmt_str_id_deref->dest.ssa,
+ nir_var_mem_global,
+ glsl_uint_type(), 0);
+ fmt_str_id_deref->cast.align_mul = 4;
+ nir_store_deref(b, fmt_str_id_deref, fmt_str_id, ~0);
+
+ /* Write the format args */
+ for (unsigned i = 0; i < glsl_get_length(args->type); ++i) {
+ nir_deref_instr *arg_deref = nir_build_deref_struct(b, args, i);
+ nir_ssa_def *arg = nir_load_deref(b, arg_deref);
+ const struct glsl_type *arg_type = arg_deref->type;
+
+ /* Clang does promotion of arguments to their "native" size. That means
+ * that any floats have been converted to doubles for the call to
+ * printf. Since doubles are optional, some drivers might not support
+ * them. For those drivers, convert them back to float before writing.
+ * Copy prop and other optimizations should remove all hints of doubles.
+ */
+ if (glsl_get_base_type(arg_type) == GLSL_TYPE_DOUBLE &&
+ options && options->treat_doubles_as_floats) {
+ arg = nir_f2f32(b, arg);
+ arg_type = glsl_float_type();
+ }
+
+ unsigned field_offset = glsl_get_struct_field_offset(args->type, i);
+ nir_ssa_def *arg_offset =
+ nir_i2i(b, nir_iadd_imm(b, offset,
+ fmt_str_id_size + field_offset),
+ ptr_bit_size);
+ nir_deref_instr *dst_arg_deref =
+ nir_build_deref_array(b, buffer, arg_offset);
+ dst_arg_deref = nir_build_deref_cast(b, &dst_arg_deref->dest.ssa,
+ nir_var_mem_global, arg_type, 0);
+ assert(field_offset % 4 == 0);
+ dst_arg_deref->cast.align_mul = 4;
+ nir_store_deref(b, dst_arg_deref, arg, ~0);
+ }
+
+ nir_push_else(b, NULL);
+ nir_ssa_def *printf_fail_val = nir_imm_int(b, -1);
+ nir_pop_if(b, NULL);
+
+ nir_ssa_def *ret_val = nir_if_phi(b, printf_succ_val, printf_fail_val);
+ nir_ssa_def_rewrite_uses(&prntf->dest.ssa, nir_src_for_ssa(ret_val));
+ nir_instr_remove(&prntf->instr);
+
+ return true;
+}
+
+bool
+nir_lower_printf(nir_shader *nir, const nir_lower_printf_options *options)
+{
+ return nir_shader_instructions_pass(nir, lower_printf_instr,
+ nir_metadata_none,
+ (void *)options);
+}