v3dv: stop incrementing UBO indices by one

This matches what we do for OpenGL, allowing us to
have the same compiler behavior for both worlds.

Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24396>

diff --git a/src/broadcom/compiler/nir_to_vir.c b/src/broadcom/compiler/nir_to_vir.c
index 4472af7..af0549a 100644 (file)
--- a/src/broadcom/compiler/nir_to_vir.c
+++ b/src/broadcom/compiler/nir_to_vir.c
@@ -564,13 +564,11 @@ ntq_emit_tmu_general(struct v3d_compile *c, nir_intrinsic_instr *instr,
                                           v3d_unit_data_create(0, const_offset));
                 const_offset = 0;
         } else if (instr->intrinsic == nir_intrinsic_load_ubo) {
-                uint32_t index = nir_src_as_uint(instr->src[0]);
-                /* On OpenGL QUNIFORM_UBO_ADDR takes a UBO index
-                 * shifted up by 1 (0 is gallium's constant buffer 0).
+                /* QUNIFORM_UBO_ADDR takes a UBO index shifted up by 1 (0
+                 * is gallium's constant buffer 0 in GL and push constants
+                 * in Vulkan)).
                  */
-                if (c->key->environment == V3D_ENVIRONMENT_OPENGL)
-                        index++;
-
+                uint32_t index = nir_src_as_uint(instr->src[0]) + 1;
                 base_offset =
                         vir_uniform(c, QUNIFORM_UBO_ADDR,
                                     v3d_unit_data_create(index, const_offset));
@@ -2741,13 +2739,10 @@ ntq_emit_inline_ubo_load(struct v3d_compile *c, nir_intrinsic_instr *instr)
         if (c->compiler->max_inline_uniform_buffers <= 0)
                 return false;
 
-        /* On Vulkan we use indices 1..MAX_INLINE_UNIFORM_BUFFERS for inline
-         * uniform buffers which we want to handle more like push constants
-         * than regular UBO. OpenGL doesn't implement this feature.
-         */
         assert(c->key->environment == V3D_ENVIRONMENT_VULKAN);
+        /* Regular UBOs start after inline UBOs */
         uint32_t index = nir_src_as_uint(instr->src[0]);
-        if (index == 0 || index > c->compiler->max_inline_uniform_buffers)
+        if (index >= c->compiler->max_inline_uniform_buffers)
                 return false;
 
         /* We scalarize general TMU access for anything that is not 32-bit */
@@ -2755,13 +2750,10 @@ ntq_emit_inline_ubo_load(struct v3d_compile *c, nir_intrinsic_instr *instr)
                instr->num_components == 1);
 
         if (nir_src_is_const(instr->src[1])) {
-                /* Index 0 is reserved for push constants */
-                assert(index > 0);
-                uint32_t inline_index = index - 1;
                 int offset = nir_src_as_uint(instr->src[1]);
                 if (try_emit_uniform(c, offset, instr->num_components,
                                      &instr->dest,
-                                     QUNIFORM_INLINE_UBO_0 + inline_index)) {
+                                     QUNIFORM_INLINE_UBO_0 + index)) {
                         return true;
                 }
         }
@@ -3159,10 +3151,11 @@ ntq_emit_load_unifa(struct v3d_compile *c, nir_intrinsic_instr *instr)
          */
         uint32_t index = is_uniform ? 0 : nir_src_as_uint(instr->src[0]);
 
-        /* On OpenGL QUNIFORM_UBO_ADDR takes a UBO index
-         * shifted up by 1 (0 is gallium's constant buffer 0).
+        /* QUNIFORM_UBO_ADDR takes a UBO index shifted up by 1 since we use
+         * index 0 for Gallium's constant buffer (GL) or push constants
+         * (Vulkan).
          */
-        if (is_ubo && c->key->environment == V3D_ENVIRONMENT_OPENGL)
+        if (is_ubo)
                 index++;
 
         /* We can only keep track of the last unifa address we used with

diff --git a/src/broadcom/compiler/vir.c b/src/broadcom/compiler/vir.c
index ec0dca7..2fa4b25 100644 (file)
--- a/src/broadcom/compiler/vir.c
+++ b/src/broadcom/compiler/vir.c
@@ -1603,7 +1603,6 @@ v3d_attempt_compile(struct v3d_compile *c)
                    .lower_image = c->key->robust_image_access,
                    .lower_ssbo = c->key->robust_storage_access,
                    .lower_ubo = c->key->robust_uniform_access,
-                   .skip_ubo_0 = c->key->environment == V3D_ENVIRONMENT_VULKAN,
                 };
 
                 NIR_PASS(_, c->s, nir_lower_robust_access, &opts);

diff --git a/src/broadcom/vulkan/v3dv_pipeline.c b/src/broadcom/vulkan/v3dv_pipeline.c
index 99fe8c1..1518d13 100644 (file)
--- a/src/broadcom/vulkan/v3dv_pipeline.c
+++ b/src/broadcom/vulkan/v3dv_pipeline.c
@@ -546,7 +546,7 @@ lower_vulkan_resource_index(nir_builder *b,
       uint32_t start_index = 0;
       if (binding_layout->type == VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER ||
           binding_layout->type == VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC) {
-         start_index = MAX_INLINE_UNIFORM_BUFFERS;
+         start_index += MAX_INLINE_UNIFORM_BUFFERS;
       }
 
       index = descriptor_map_add(descriptor_map, set, binding,
@@ -555,14 +555,6 @@ lower_vulkan_resource_index(nir_builder *b,
                                  start_index,
                                  32 /* return_size: doesn't really apply for this case */,
                                  0);
-
-      /* We always reserve index 0 for push constants */
-      if (binding_layout->type == VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER ||
-          binding_layout->type == VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC ||
-          binding_layout->type == VK_DESCRIPTOR_TYPE_INLINE_UNIFORM_BLOCK) {
-         index++;
-      }
-
       break;
    }
 

diff --git a/src/broadcom/vulkan/v3dv_uniforms.c b/src/broadcom/vulkan/v3dv_uniforms.c
index 72fa9a1..2d3f017 100644 (file)
--- a/src/broadcom/vulkan/v3dv_uniforms.c
+++ b/src/broadcom/vulkan/v3dv_uniforms.c
@@ -288,9 +288,10 @@ write_ubo_ssbo_uniforms(struct v3dv_cmd_buffer *cmd_buffer,
                                offset + dynamic_offset);
    } else {
       if (content == QUNIFORM_UBO_ADDR) {
-         /* We reserve index 0 for push constants and artificially increase our
-          * indices by one for that reason, fix that now before accessing the
-          * descriptor map.
+         /* We reserve UBO index 0 for push constants in Vulkan (and for the
+          * constant buffer in GL) so the compiler always adds one to all UBO
+          * indices, fix it up before we access the descriptor map, since
+          * indices start from 0 there.
           */
          assert(index > 0);
          index--;