nir: Add multiplier argument to nir_lower_uniforms_to_ubo.

Note that locations can be set in different units, and the multiplier
argument caters to supporting these different units. For example,
st_glsl_to_nir uses dwords (4 bytes) so the multiplier should be 4,
while tgsi_to_nir uses bytes, so the multiplier should be 16.

Signed-Off-By: Timur Kristóf <timur.kristof@gmail.com>
Tested-by: Andre Heider <a.heider@gmail.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

src/compiler/nir/nir.h

@@ -3036,7 +3036,7 @@ void nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader,
 void nir_lower_io_to_scalar(nir_shader *shader, nir_variable_mode mask);
 void nir_lower_io_to_scalar_early(nir_shader *shader, nir_variable_mode mask);
 
-bool nir_lower_uniforms_to_ubo(nir_shader *shader);
+bool nir_lower_uniforms_to_ubo(nir_shader *shader, int multiplier);
 
 typedef struct nir_lower_subgroups_options {
    uint8_t subgroup_size;

src/compiler/nir/nir_lower_uniforms_to_ubo.c

@@ -22,18 +22,24 @@
  */
 
 /*
- * Remap load_uniform intrinsics to UBO accesses of UBO binding point 0. Both
- * the base and the offset are interpreted as 16-byte units.
- *
+ * Remap load_uniform intrinsics to UBO accesses of UBO binding point 0.
  * Simultaneously, remap existing UBO accesses by increasing their binding
  * point by 1.
+ *
+ * Both the base and the offset are interpreted as 16-byte units.
+ *
+ * Note that locations can be set in different units, and the multiplier
+ * argument caters to supporting these different units.
+ * For example:
+ * - st_glsl_to_nir uses dwords (4 bytes) so the multiplier should be 4
+ * - tgsi_to_nir uses bytes, so the multiplier should be 16
  */
 
 #include "nir.h"
 #include "nir_builder.h"
 
 static bool
-lower_instr(nir_intrinsic_instr *instr, nir_builder *b)
+lower_instr(nir_intrinsic_instr *instr, nir_builder *b, int multiplier)
 {
    b->cursor = nir_before_instr(&instr->instr);
 
@@ -48,8 +54,8 @@ lower_instr(nir_intrinsic_instr *instr, nir_builder *b)
    if (instr->intrinsic == nir_intrinsic_load_uniform) {
       nir_ssa_def *ubo_idx = nir_imm_int(b, 0);
       nir_ssa_def *ubo_offset =
-         nir_iadd(b, nir_imm_int(b, 4 * nir_intrinsic_base(instr)),
-                  nir_imul(b, nir_imm_int(b, 4),
+         nir_iadd(b, nir_imm_int(b, multiplier * nir_intrinsic_base(instr)),
+                  nir_imul(b, nir_imm_int(b, multiplier),
                            nir_ssa_for_src(b, instr->src[0], 1)));
 
       nir_intrinsic_instr *load =
@@ -71,7 +77,7 @@ lower_instr(nir_intrinsic_instr *instr, nir_builder *b)
 }
 
 bool
-nir_lower_uniforms_to_ubo(nir_shader *shader)
+nir_lower_uniforms_to_ubo(nir_shader *shader, int multiplier)
 {
    bool progress = false;
 
@@ -83,7 +89,8 @@ nir_lower_uniforms_to_ubo(nir_shader *shader)
             nir_foreach_instr_safe(instr, block) {
                if (instr->type == nir_instr_type_intrinsic)
                   progress |= lower_instr(nir_instr_as_intrinsic(instr),
-                                          &builder);
+                                          &builder,
+                                          multiplier);
             }
          }
 

src/mesa/state_tracker/st_glsl_to_nir.cpp

@@ -991,7 +991,7 @@ st_finalize_nir(struct st_context *st, struct gl_program *prog,
    if (st->ctx->Const.PackedDriverUniformStorage) {
       NIR_PASS_V(nir, nir_lower_io, nir_var_uniform, st_glsl_type_dword_size,
                  (nir_lower_io_options)0);
-      NIR_PASS_V(nir, nir_lower_uniforms_to_ubo);
+      NIR_PASS_V(nir, nir_lower_uniforms_to_ubo, 4);
    }
 
    st_nir_lower_samplers(screen, nir, shader_program, prog);

src/mesa/state_tracker/st_nir_builtins.c

@@ -66,7 +66,7 @@ st_nir_finish_builtin_shader(struct st_context *st,
    if (st->ctx->Const.PackedDriverUniformStorage) {
       NIR_PASS_V(nir, nir_lower_io, nir_var_uniform, st_glsl_type_dword_size,
                  (nir_lower_io_options)0);
-      NIR_PASS_V(nir, nir_lower_uniforms_to_ubo);
+      NIR_PASS_V(nir, nir_lower_uniforms_to_ubo, 4);
    }
 
    struct pipe_shader_state state = {