From 8defd1bc16de53e32bd4ea349c16d0f48612ca80 Mon Sep 17 00:00:00 2001
From: Rhys Perry <pendingchaos02@gmail.com>
Date: Mon, 2 Jun 2025 14:47:25 +0100
Subject: [PATCH] aco/gfx6: disallow global access with sgpr address and two
 offsets
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No fossil-db changes (navi10, pitcairn).

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35465>
---
 .../instruction_selection/aco_select_nir_intrinsics.cpp       | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/amd/compiler/instruction_selection/aco_select_nir_intrinsics.cpp b/src/amd/compiler/instruction_selection/aco_select_nir_intrinsics.cpp
index 660b16c34e2..aa1438cff57 100644
--- a/src/amd/compiler/instruction_selection/aco_select_nir_intrinsics.cpp
+++ b/src/amd/compiler/instruction_selection/aco_select_nir_intrinsics.cpp
@@ -846,7 +846,9 @@ lower_global_address(Builder& bld, uint32_t offset_in, Temp* address_inout,
 
    if (bld.program->gfx_level == GFX6) {
       /* GFX6 (MUBUF): (SGPR address, SGPR offset) or (VGPR address, SGPR offset) */
-      if (offset.type() != RegType::sgpr) {
+      /* Disallow SGPR address with both a const_offset and offset because of possible overflow. */
+      if (offset.id() && (offset.type() != RegType::sgpr ||
+                          (address.type() == RegType::sgpr && const_offset > 0))) {
          address = add64_32(bld, address, offset);
          offset = Temp();
       }