From 8f33896822f37bbdb166473dc2f13839b58cc06e Mon Sep 17 00:00:00 2001
From: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Date: Thu, 12 Mar 2026 14:34:49 +0100
Subject: [PATCH] radv: pre-compute the primitive restart index

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40775>
---
 src/amd/vulkan/radv_cmd_buffer.c | 49 ++++++++++++++++----------------
 src/amd/vulkan/radv_cmd_buffer.h |  3 +-
 2 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/src/amd/vulkan/radv_cmd_buffer.c b/src/amd/vulkan/radv_cmd_buffer.c
index 3ea60bc681d..3b6cde8c419 100644
--- a/src/amd/vulkan/radv_cmd_buffer.c
+++ b/src/amd/vulkan/radv_cmd_buffer.c
@@ -4391,22 +4391,6 @@ radv_emit_fsr_state(struct radv_cmd_buffer *cmd_buffer)
    radeon_end();
 }
 
-static uint32_t
-radv_get_primitive_reset_index(const struct radv_cmd_buffer *cmd_buffer)
-{
-   const uint32_t index_type = G_028A7C_INDEX_TYPE(cmd_buffer->state.index_type);
-   switch (index_type) {
-   case V_028A7C_VGT_INDEX_8:
-      return 0xffu;
-   case V_028A7C_VGT_INDEX_16:
-      return 0xffffu;
-   case V_028A7C_VGT_INDEX_32:
-      return 0xffffffffu;
-   default:
-      UNREACHABLE("invalid index type");
-   }
-}
-
 static void
 radv_emit_ls_hs_config(struct radv_cmd_buffer *cmd_buffer)
 {
@@ -7283,10 +7267,8 @@ radv_emit_primitive_restart(struct radv_cmd_buffer *cmd_buffer, bool enable)
        * GFX9+: Default is same as GFX8, MATCH_ALL_BITS=1 selects GFX6-7 behavior
        */
       if (enable && gfx_level <= GFX7) {
-         const uint32_t primitive_reset_index = radv_get_primitive_reset_index(cmd_buffer);
-
          radeon_opt_set_context_reg(R_02840C_VGT_MULTI_PRIM_IB_RESET_INDX, AC_TRACKED_VGT_MULTI_PRIM_IB_RESET_INDX,
-                                    primitive_reset_index);
+                                    cmd_buffer->state.primitive_restart_index);
       }
    }
 
@@ -7301,7 +7283,6 @@ radv_emit_draw_registers(struct radv_cmd_buffer *cmd_buffer, const struct radv_d
    const struct radv_dynamic_state *d = &cmd_buffer->state.dynamic;
    const bool primitive_restart_en =
       (draw_info->indexed || pdev->info.gfx_level >= GFX11) && d->vk.ia.primitive_restart_enable;
-   const uint32_t primitive_reset_index = radv_get_primitive_reset_index(cmd_buffer);
    const struct radeon_info *gpu_info = &pdev->info;
    struct radv_cmd_state *state = &cmd_buffer->state;
    struct radv_cmd_stream *cs = cmd_buffer->cs;
@@ -7348,10 +7329,10 @@ radv_emit_draw_registers(struct radv_cmd_buffer *cmd_buffer, const struct radv_d
    }
 
    if (primitive_restart_en != state->last_primitive_restart_en ||
-       (pdev->info.gfx_level <= GFX7 && primitive_reset_index != state->last_primitive_reset_index)) {
+       (pdev->info.gfx_level <= GFX7 && state->primitive_restart_index != state->last_primitive_restart_index)) {
       radv_emit_primitive_restart(cmd_buffer, primitive_restart_en);
       state->last_primitive_restart_en = primitive_restart_en;
-      state->last_primitive_reset_index = primitive_reset_index;
+      state->last_primitive_restart_index = state->primitive_restart_index;
    }
 }
 
@@ -8019,6 +8000,21 @@ vk_to_index_type(VkIndexType type)
    }
 }
 
+static uint32_t
+radv_get_primitive_restart_index(VkIndexType type)
+{
+   switch (type) {
+   case VK_INDEX_TYPE_UINT8:
+      return 0xffu;
+   case VK_INDEX_TYPE_UINT16:
+      return 0xffffu;
+   case VK_INDEX_TYPE_UINT32:
+      return 0xffffffffu;
+   default:
+      UNREACHABLE("invalid index type");
+   }
+}
+
 static uint32_t
 radv_get_vgt_index_size(uint32_t type)
 {
@@ -8067,6 +8063,7 @@ radv_CmdBindIndexBuffer3KHR(VkCommandBuffer commandBuffer, const VkBindIndexBuff
    VK_FROM_HANDLE(radv_cmd_buffer, cmd_buffer, commandBuffer);
 
    cmd_buffer->state.index_type = vk_to_index_type(pInfo->indexType);
+   cmd_buffer->state.primitive_restart_index = radv_get_primitive_restart_index(pInfo->indexType);
 
    if (pInfo->addressRange.size) {
       cmd_buffer->state.index_va = pInfo->addressRange.address;
@@ -9921,8 +9918,12 @@ radv_CmdExecuteCommands(VkCommandBuffer commandBuffer, uint32_t commandBufferCou
          primary->state.last_primitive_restart_en = secondary->state.last_primitive_restart_en;
       }
 
-      if (secondary->state.last_primitive_reset_index) {
-         primary->state.last_primitive_reset_index = secondary->state.last_primitive_reset_index;
+      if (secondary->state.primitive_restart_index) {
+         primary->state.primitive_restart_index = secondary->state.primitive_restart_index;
+      }
+
+      if (secondary->state.last_primitive_restart_index) {
+         primary->state.last_primitive_restart_index = secondary->state.last_primitive_restart_index;
       }
 
       primary->state.rb_noncoherent_dirty |= secondary->state.rb_noncoherent_dirty;
diff --git a/src/amd/vulkan/radv_cmd_buffer.h b/src/amd/vulkan/radv_cmd_buffer.h
index 2cd9b196ace..a6665713ae2 100644
--- a/src/amd/vulkan/radv_cmd_buffer.h
+++ b/src/amd/vulkan/radv_cmd_buffer.h
@@ -356,7 +356,8 @@ struct radv_cmd_state {
 
    /* Primitive restart */
    int32_t last_primitive_restart_en;
-   uint32_t last_primitive_reset_index;
+   uint32_t primitive_restart_index;
+   uint32_t last_primitive_restart_index;
 
    enum radv_cmd_flush_bits flush_bits;
    unsigned active_occlusion_queries;