[PATCH 4/4] wined3d: Add a setting to turn off aggressive optimization on NVIDIA.

[Henri Verbeet]

From: Paul Gofman <gofmanp at gmail.com>

NVIDIA drivers perform too aggressive optimization involving change
of computation order (aka 'fastmath') by default. The setting
helps to workaround bugs like https://bugs.winehq.org/show_bug.cgi?id=35207.

Signed-off-by: Henri Verbeet <hverbeet at codeweavers.com>
---
 dlls/wined3d/glsl_shader.c     | 3 +++
 dlls/wined3d/wined3d_main.c    | 3 +++
 dlls/wined3d/wined3d_private.h | 1 +
 3 files changed, 7 insertions(+)

diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c
index 660005f57e9..4613d78f94c 100644
--- a/dlls/wined3d/glsl_shader.c
+++ b/dlls/wined3d/glsl_shader.c
@@ -2416,6 +2416,9 @@ static void shader_generate_glsl_declarations(const struct wined3d_context *cont
     unsigned int i;
     DWORD map;
 
+    if (wined3d_settings.strict_shader_math)
+        shader_addline(buffer, "#pragma optionNV(fastmath off)\n");
+
     prefix = shader_glsl_get_prefix(version->type);
 
     /* Prototype the subroutines */
diff --git a/dlls/wined3d/wined3d_main.c b/dlls/wined3d/wined3d_main.c
index 1b64d2cf5dc..fb70b946770 100644
--- a/dlls/wined3d/wined3d_main.c
+++ b/dlls/wined3d/wined3d_main.c
@@ -82,6 +82,7 @@ struct wined3d_settings wined3d_settings =
     TRUE,           /* Prefer multisample textures to multisample renderbuffers. */
     ~0u,            /* Don't force a specific sample count by default. */
     FALSE,          /* Don't range check relative addressing indices in float constants. */
+    FALSE,          /* No strict shader math by default. */
     ~0U,            /* No VS shader model limit by default. */
     ~0U,            /* No HS shader model limit by default. */
     ~0U,            /* No DS shader model limit by default. */
@@ -312,6 +313,8 @@ static BOOL wined3d_dll_init(HINSTANCE hInstDLL)
             TRACE("Checking relative addressing indices in float constants.\n");
             wined3d_settings.check_float_constants = TRUE;
         }
+        if (!get_config_key_dword(hkey, appkey, "strict_shader_math", &wined3d_settings.strict_shader_math))
+            ERR_(winediag)("Setting strict shader math to %#x.\n", wined3d_settings.strict_shader_math);
         if (!get_config_key_dword(hkey, appkey, "MaxShaderModelVS", &wined3d_settings.max_sm_vs))
             TRACE("Limiting VS shader model to %u.\n", wined3d_settings.max_sm_vs);
         if (!get_config_key_dword(hkey, appkey, "MaxShaderModelHS", &wined3d_settings.max_sm_hs))
diff --git a/dlls/wined3d/wined3d_private.h b/dlls/wined3d/wined3d_private.h
index b3f3847045d..f2b9b5feb25 100644
--- a/dlls/wined3d/wined3d_private.h
+++ b/dlls/wined3d/wined3d_private.h
@@ -398,6 +398,7 @@ struct wined3d_settings
     unsigned int multisample_textures;
     unsigned int sample_count;
     BOOL check_float_constants;
+    unsigned int strict_shader_math;
     unsigned int max_sm_vs;
     unsigned int max_sm_hs;
     unsigned int max_sm_ds;
-- 
2.11.0