shader_recompiler: Align SSBO offsets in GlobalMemory functions

4 files changed, 15 insertions, 5 deletions

diff --git a/src/shader_recompiler/backend/glasm/emit_glasm_memory.cpp b/src/shader_recompiler/backend/glasm/emit_glasm_memory.cpp
index 2705ab140..9319ea007 100644
--- a/src/shader_recompiler/backend/glasm/emit_glasm_memory.cpp
+++ b/src/shader_recompiler/backend/glasm/emit_glasm_memory.cpp
@@ -5,6 +5,7 @@
 #include "shader_recompiler/backend/glasm/glasm_emit_context.h"
 #include "shader_recompiler/frontend/ir/program.h"
 #include "shader_recompiler/frontend/ir/value.h"
+#include "shader_recompiler/profile.h"
 #include "shader_recompiler/runtime_info.h"
 
 namespace Shader::Backend::GLASM {
@@ -35,7 +36,9 @@ void GlobalStorageOp(EmitContext& ctx, Register address, bool pointer_based, std
             continue;
         }
         const auto& ssbo{ctx.info.storage_buffers_descriptors[index]};
-        ctx.Add("LDC.U64 DC.x,c{}[{}];"    // ssbo_addr
+        const u64 ssbo_align_mask{~(ctx.profile.min_ssbo_alignment - 1U)};
+        ctx.Add("LDC.U64 DC.x,c{}[{}];"    // unaligned_ssbo_addr
+                "AND.U64 DC.x,DC.x,{};"    // ssbo_addr = unaligned_ssbo_addr & ssbo_align_mask
                 "LDC.U32 RC.x,c{}[{}];"    // ssbo_size_u32
                 "CVT.U64.U32 DC.y,RC.x;"   // ssbo_size = ssbo_size_u32
                 "ADD.U64 DC.y,DC.y,DC.x;"  // ssbo_end = ssbo_addr + ssbo_size
@@ -44,8 +47,8 @@ void GlobalStorageOp(EmitContext& ctx, Register address, bool pointer_based, std
                 "AND.U.CC RC.x,RC.x,RC.y;" // cond = a && b
                 "IF NE.x;"                 // if cond
                 "SUB.U64 DC.x,{}.x,DC.x;", // offset = input_addr - ssbo_addr
-                ssbo.cbuf_index, ssbo.cbuf_offset, ssbo.cbuf_index, ssbo.cbuf_offset + 8, address,
-                address, address);
+                ssbo.cbuf_index, ssbo.cbuf_offset, ssbo_align_mask, ssbo.cbuf_index,
+                ssbo.cbuf_offset + 8, address, address, address);
         if (pointer_based) {
             ctx.Add("PK64.U DC.y,c[{}];"      // host_ssbo = cbuf
                     "ADD.U64 DC.x,DC.x,DC.y;" // host_addr = host_ssbo + offset
diff --git a/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp b/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp
index 9ff4028c2..fd9a99449 100644
--- a/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp
+++ b/src/shader_recompiler/backend/glsl/glsl_emit_context.cpp
@@ -601,7 +601,10 @@ std::string EmitContext::DefineGlobalMemoryFunctions() {
             addr_xy[i] = fmt::format("ftou({}[{}].{})", cbuf, addr_loc / 16, Swizzle(addr_loc));
             size_xy[i] = fmt::format("ftou({}[{}].{})", cbuf, size_loc / 16, Swizzle(size_loc));
         }
-        const auto addr_pack{fmt::format("packUint2x32(uvec2({},{}))", addr_xy[0], addr_xy[1])};
+        const u32 ssbo_align_mask{~(static_cast<u32>(profile.min_ssbo_alignment) - 1U)};
+        const auto aligned_low_addr{fmt::format("{}&{}", addr_xy[0], ssbo_align_mask)};
+        const auto aligned_addr{fmt::format("uvec2({},{})", aligned_low_addr, addr_xy[1])};
+        const auto addr_pack{fmt::format("packUint2x32({})", aligned_addr)};
         const auto addr_statment{fmt::format("uint64_t {}={};", ssbo_addr, addr_pack)};
         func += addr_statment;
 
diff --git a/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp b/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
index 57df6fc34..3350f1f85 100644
--- a/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
+++ b/src/shader_recompiler/backend/spirv/spirv_emit_context.cpp
@@ -891,7 +891,9 @@ void EmitContext::DefineGlobalMemoryFunctions(const Info& info) {
             const Id ssbo_size_pointer{OpAccessChain(uniform_types.U32, cbufs[ssbo.cbuf_index].U32,
                                                      zero, ssbo_size_cbuf_offset)};
 
-            const Id ssbo_addr{OpBitcast(U64, OpLoad(U32[2], ssbo_addr_pointer))};
+            const u64 ssbo_align_mask{~(profile.min_ssbo_alignment - 1U)};
+            const Id unaligned_addr{OpBitcast(U64, OpLoad(U32[2], ssbo_addr_pointer))};
+            const Id ssbo_addr{OpBitwiseAnd(U64, unaligned_addr, Constant(U64, ssbo_align_mask))};
             const Id ssbo_size{OpUConvert(U64, OpLoad(U32[1], ssbo_size_pointer))};
             const Id ssbo_end{OpIAdd(U64, ssbo_addr, ssbo_size)};
             const Id cond{OpLogicalAnd(U1, OpUGreaterThanEqual(U1, addr, ssbo_addr),
diff --git a/src/shader_recompiler/profile.h b/src/shader_recompiler/profile.h
index 38d820db2..e62ba8a20 100644
--- a/src/shader_recompiler/profile.h
+++ b/src/shader_recompiler/profile.h
@@ -84,6 +84,8 @@ struct Profile {
 
     /// Maxwell and earlier nVidia architectures have broken robust support
     bool has_broken_robust{};
+
+    u64 min_ssbo_alignment{};
 };
 
 } // namespace Shader