diff --git a/dlls/d3dx9_36/d3dx9_36.spec b/dlls/d3dx9_36/d3dx9_36.spec
index d3fe3acad7c..0d39114ef7e 100644
--- a/dlls/d3dx9_36/d3dx9_36.spec
+++ b/dlls/d3dx9_36/d3dx9_36.spec
@@ -1,6 +1,6 @@
-@ stub D3DXAssembleShader
-@ stub D3DXAssembleShaderFromFileA
-@ stub D3DXAssembleShaderFromFileW
+@ stdcall D3DXAssembleShader(ptr long ptr ptr long ptr ptr)
+@ stdcall D3DXAssembleShaderFromFileA(str ptr ptr long ptr ptr)
+@ stdcall D3DXAssembleShaderFromFileW(wstr ptr ptr long ptr ptr)
 @ stub D3DXAssembleShaderFromResourceA
 @ stub D3DXAssembleShaderFromResourceW
 @ stdcall D3DXBoxBoundProbe(ptr ptr ptr ptr)
diff --git a/dlls/d3dx9_36/shader.c b/dlls/d3dx9_36/shader.c
index 48499ac6df1..97b23842375 100644
--- a/dlls/d3dx9_36/shader.c
+++ b/dlls/d3dx9_36/shader.c
@@ -19,6 +19,7 @@
 #include "config.h"
 #include "wine/port.h"
 #include "wine/debug.h"
+#include "wine/unicode.h"
 #include "windef.h"
 #include "wingdi.h"
 #include "d3dx9.h"
@@ -131,3 +132,50 @@ LPCSTR WINAPI D3DXGetVertexShaderProfile(LPDIRECT3DDEVICE9 device)
 
     return NULL;
 }
+
+HRESULT WINAPI D3DXAssembleShader(LPCSTR data,
+                                  UINT data_len,
+                                  CONST D3DXMACRO* defines,
+                                  LPD3DXINCLUDE include,
+                                  DWORD flags,
+                                  LPD3DXBUFFER* shader,
+                                  LPD3DXBUFFER* error_messages)
+{
+    FIXME("stub\n");
+    return D3DERR_INVALIDCALL;
+}
+
+HRESULT WINAPI D3DXAssembleShaderFromFileA(LPCSTR filename,
+                                           CONST D3DXMACRO* defines,
+                                           LPD3DXINCLUDE include,
+                                           DWORD flags,
+                                           LPD3DXBUFFER* shader,
+                                           LPD3DXBUFFER* error_messages)
+{
+    LPWSTR filename_w = NULL;
+    DWORD len;
+    HRESULT ret;
+
+    if (!filename) return D3DXERR_INVALIDDATA;
+
+    len = MultiByteToWideChar(CP_ACP, 0, filename, -1, NULL, 0);
+    filename_w = HeapAlloc(GetProcessHeap(), 0, len * sizeof(WCHAR));
+    if (!filename_w) return E_OUTOFMEMORY;
+    MultiByteToWideChar(CP_ACP, 0, filename, -1, filename_w, len);
+
+    ret = D3DXAssembleShaderFromFileW(filename_w, defines, include, flags, shader, error_messages);
+
+    HeapFree(GetProcessHeap(), 0, filename_w);
+    return ret;
+}
+
+HRESULT WINAPI D3DXAssembleShaderFromFileW(LPCWSTR filename,
+                                           CONST D3DXMACRO* defines,
+                                           LPD3DXINCLUDE include,
+                                           DWORD flags,
+                                           LPD3DXBUFFER* shader,
+                                           LPD3DXBUFFER* error_messages)
+{
+    FIXME("stub\n");
+    return D3DERR_INVALIDCALL;
+}