diff --git a/renderdoc/data/hlsl/hlsl_cbuffers.h b/renderdoc/data/hlsl/hlsl_cbuffers.h
index d0464e951..76ed2a084 100644
--- a/renderdoc/data/hlsl/hlsl_cbuffers.h
+++ b/renderdoc/data/hlsl/hlsl_cbuffers.h
@@ -288,6 +288,13 @@ struct InstanceDesc
 
 cbuffer RayDispatchPatchCB REG(b0)
 {
+  // declare GPUAddresses first to avoid padding/alignment issues
+  GPUAddress wrapped_sampHeapBase;
+  GPUAddress wrapped_srvHeapBase;
+
+  GPUAddress unwrapped_sampHeapBase;
+  GPUAddress unwrapped_srvHeapBase;
+
   uint raydispatch_missoffs;
   uint raydispatch_missstride;
   uint raydispatch_misscount;
@@ -300,12 +307,6 @@ cbuffer RayDispatchPatchCB REG(b0)
   uint raydispatch_callstride;
   uint raydispatch_callcount;
 
-  GPUAddress wrapped_sampHeapBase;
-  GPUAddress wrapped_srvHeapBase;
-
-  GPUAddress unwrapped_sampHeapBase;
-  GPUAddress unwrapped_srvHeapBase;
-
   uint wrapped_sampHeapSize;
   uint wrapped_srvHeapSize;
   uint unwrapped_heapStrides;    // LSB = sampler, MSB = srv
@@ -313,7 +314,28 @@ cbuffer RayDispatchPatchCB REG(b0)
   uint numPatchingAddrs;
 };
 
+struct StateObjectLookup
+{
+  uint2 id;    // ResourceId
+  uint offset;
+
+  uint pad;
+};
+
+struct ShaderRecordData
+{
+  uint4 identifier[2];    // 32-byte real identifier
+  uint rootSigIndex;      // only lower 16-bits are valid
+};
+
 #define MAX_LOCALSIG_PARAMS 31
+
+struct LocalRootSigData
+{
+  uint numParams;
+  uint paramOffsets[MAX_LOCALSIG_PARAMS];
+};
+
 #define WRAPPED_DESCRIPTOR_STRIDE 64
 
 cbuffer DebugSampleOperation REG(b0)
diff --git a/renderdoc/data/hlsl/raytracing.hlsl b/renderdoc/data/hlsl/raytracing.hlsl
index f57c4119a..51b64a1db 100644
--- a/renderdoc/data/hlsl/raytracing.hlsl
+++ b/renderdoc/data/hlsl/raytracing.hlsl
@@ -57,29 +57,9 @@ bool InRange(BlasAddressRange addressRange, GPUAddress address)
   instanceDescs[dispatchGroup.x].blasAddress = 0;
 }
 
-struct StateObjectLookup
-{
-  uint2 id;    // ResourceId
-  uint offset;
-};
-
 StructuredBuffer<StateObjectLookup> stateObjects : register(t0);
-
-struct RecordData
-{
-  uint4 identifier[2];    // 32-byte real identifier
-  uint rootSigIndex;      // only lower 16-bits are valid
-};
-
-StructuredBuffer<RecordData> records : register(t1);
-
-struct RootSig
-{
-  uint numParams;
-  uint paramOffsets[MAX_LOCALSIG_PARAMS];
-};
-
-StructuredBuffer<RootSig> rootsigs : register(t2);
+StructuredBuffer<ShaderRecordData> records : register(t1);
+StructuredBuffer<LocalRootSigData> rootsigs : register(t2);
 
 struct WrappedRecord
 {
@@ -136,7 +116,7 @@ void PatchTable(uint byteOffset)
 
   // the exports from this state object are contiguous starting from the given index, look up this
   // identifier's export
-  RecordData recordData = records[objectLookup.offset + wrappedRecord.index];
+  ShaderRecordData recordData = records[objectLookup.offset + wrappedRecord.index];
 
   // store the unwrapped shader identifier
   bufferToPatch.Store4(byteOffset, recordData.identifier[0]);
@@ -146,7 +126,7 @@ void PatchTable(uint byteOffset)
 
   if(rootSigIndex != 0xffff)
   {
-    RootSig sig = rootsigs[rootSigIndex];
+    LocalRootSigData sig = rootsigs[rootSigIndex];
 
     DescriptorHeapData heaps[2];
 
@@ -181,8 +161,8 @@ void PatchTable(uint byteOffset)
             uint index = sub(wrappedHandlePtr, heaps[h].wrapped_base).x / WRAPPED_DESCRIPTOR_STRIDE;
 
             GPUAddress handleOffset = GPUAddress(index * heaps[h].unwrapped_stride, 0);
-            bufferToPatch.Store2(byteOffset + paramOffset,
-                                 add(heaps[h].unwrapped_base, handleOffset));
+            GPUAddress unwrapped = add(heaps[h].unwrapped_base, handleOffset);
+            bufferToPatch.Store2(byteOffset + paramOffset, unwrapped);
             patched = true;
             break;
           }
diff --git a/renderdoc/driver/d3d12/d3d12_manager.cpp b/renderdoc/driver/d3d12/d3d12_manager.cpp
index c1b8d94e2..136650733 100644
--- a/renderdoc/driver/d3d12/d3d12_manager.cpp
+++ b/renderdoc/driver/d3d12/d3d12_manager.cpp
@@ -837,6 +837,8 @@ PatchedRayDispatch D3D12RaytracingResourceAndUtilHandler::PatchRayDispatch(
 
   D3D12GpuBuffer *scratchBuffer = NULL;
 
+  RayDispatchPatchCB cbufferData = {};
+
   uint32_t patchDataSize = 0;
 
   const uint32_t raygenOffs = patchDataSize;
@@ -854,6 +856,30 @@ PatchedRayDispatch D3D12RaytracingResourceAndUtilHandler::PatchRayDispatch(
   const uint32_t callOffs = patchDataSize;
   patchDataSize += (uint32_t)desc.CallableShaderTable.SizeInBytes;
 
+  cbufferData.raydispatch_missoffs = missOffs;
+  cbufferData.raydispatch_missstride = (uint32_t)desc.MissShaderTable.StrideInBytes;
+  if(desc.MissShaderTable.SizeInBytes > 0)
+    cbufferData.raydispatch_misscount =
+        desc.MissShaderTable.StrideInBytes == 0
+            ? 1
+            : uint32_t(desc.MissShaderTable.SizeInBytes / desc.MissShaderTable.StrideInBytes);
+
+  cbufferData.raydispatch_hitoffs = hitOffs;
+  cbufferData.raydispatch_hitstride = (uint32_t)desc.HitGroupTable.StrideInBytes;
+  if(desc.HitGroupTable.SizeInBytes > 0)
+    cbufferData.raydispatch_hitcount =
+        desc.HitGroupTable.StrideInBytes == 0
+            ? 1
+            : uint32_t(desc.HitGroupTable.SizeInBytes / desc.HitGroupTable.StrideInBytes);
+
+  cbufferData.raydispatch_calloffs = callOffs;
+  cbufferData.raydispatch_callstride = (uint32_t)desc.CallableShaderTable.StrideInBytes;
+  if(desc.CallableShaderTable.SizeInBytes > 0)
+    cbufferData.raydispatch_callcount =
+        desc.CallableShaderTable.StrideInBytes == 0
+            ? 1
+            : uint32_t(desc.CallableShaderTable.SizeInBytes / desc.CallableShaderTable.StrideInBytes);
+
   D3D12GpuBufferAllocator::Inst()->Alloc(
       D3D12GpuBufferHeapType::DefaultHeapWithUav, D3D12GpuBufferHeapMemoryFlag::Default,
       patchDataSize, D3D12_RAYTRACING_SHADER_TABLE_BYTE_ALIGNMENT, &scratchBuffer);
@@ -969,32 +995,6 @@ PatchedRayDispatch D3D12RaytracingResourceAndUtilHandler::PatchRayDispatch(
     unwrappedCmd->ResourceBarrier(1, &barrier);
   }
 
-  RayDispatchPatchCB cbufferData = {};
-
-  cbufferData.raydispatch_missoffs = missOffs;
-  cbufferData.raydispatch_missstride = (uint32_t)desc.MissShaderTable.StrideInBytes;
-  if(desc.MissShaderTable.SizeInBytes > 0)
-    cbufferData.raydispatch_misscount =
-        desc.MissShaderTable.StrideInBytes == 0
-            ? 1
-            : uint32_t(desc.MissShaderTable.SizeInBytes / desc.MissShaderTable.StrideInBytes);
-
-  cbufferData.raydispatch_hitoffs = hitOffs;
-  cbufferData.raydispatch_hitstride = (uint32_t)desc.HitGroupTable.StrideInBytes;
-  if(desc.HitGroupTable.SizeInBytes > 0)
-    cbufferData.raydispatch_hitcount =
-        desc.HitGroupTable.StrideInBytes == 0
-            ? 1
-            : uint32_t(desc.HitGroupTable.SizeInBytes / desc.HitGroupTable.StrideInBytes);
-
-  cbufferData.raydispatch_calloffs = callOffs;
-  cbufferData.raydispatch_callstride = (uint32_t)desc.CallableShaderTable.StrideInBytes;
-  if(desc.CallableShaderTable.SizeInBytes > 0)
-    cbufferData.raydispatch_callcount =
-        desc.CallableShaderTable.StrideInBytes == 0
-            ? 1
-            : uint32_t(desc.CallableShaderTable.SizeInBytes / desc.CallableShaderTable.StrideInBytes);
-
   RDCCOMPILE_ASSERT(WRAPPED_DESCRIPTOR_STRIDE == sizeof(D3D12Descriptor),
                     "Shader descriptor stride is wrong");
 
@@ -1068,9 +1068,12 @@ void D3D12RaytracingResourceAndUtilHandler::PrepareRayDispatchBuffer(
 
     bytebuf lookupData;
 
-    const size_t ObjectLookupStride = sizeof(ResourceId) + sizeof(uint32_t);
+    const size_t ObjectLookupStride = sizeof(StateObjectLookup);
     const size_t RecordDataStride = sizeof(D3D12ShaderExportDatabase::ExportedIdentifier);
-    const size_t RootSigStride = sizeof(uint32_t) * 32;
+    const size_t RootSigStride = sizeof(LocalRootSigData);
+
+    RDCCOMPILE_ASSERT(int(ObjectLookupStride / 8) * 8 == ObjectLookupStride, "Not aligned");
+    RDCCOMPILE_ASSERT(RecordDataStride == sizeof(ShaderRecordData), "Not identically sized");
 
     size_t numExports = 0;
     for(size_t i = 0; i < m_ExportDatabases.size(); i++)