[PATCH 4/5] wined3d: Properly compare integers in wined3d_pipeline_layout_vk_compare().
Henri Verbeet
hverbeet at codeweavers.com
Thu Jan 20 10:30:56 CST 2022
As pointed out by Giovanni, modular subtraction doesn't produce a total order;
in particular, it's not transitive. For the values likely to be encountered by
wined3d_pipeline_layout_vk_compare(), this is perhaps unlikely to be an issue
in practice. However, that's not necessarily the case for e.g. handles or
masks.
Signed-off-by: Henri Verbeet <hverbeet at codeweavers.com>
---
dlls/wined3d/context_vk.c | 5 +++--
dlls/wined3d/wined3d_private.h | 5 +++++
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/dlls/wined3d/context_vk.c b/dlls/wined3d/context_vk.c
index fd6d810f0e2..cf6247387ca 100644
--- a/dlls/wined3d/context_vk.c
+++ b/dlls/wined3d/context_vk.c
@@ -1797,9 +1797,10 @@ static int wined3d_pipeline_layout_vk_compare(const void *key, const struct wine
const struct wined3d_pipeline_layout_key_vk *a = key;
const struct wined3d_pipeline_layout_key_vk *b = &WINE_RB_ENTRY_VALUE(entry,
const struct wined3d_pipeline_layout_vk, entry)->key;
+ int ret;
- if (a->binding_count != b->binding_count)
- return a->binding_count - b->binding_count;
+ if ((ret = wined3d_uint32_compare(a->binding_count, b->binding_count)))
+ return ret;
return memcmp(a->bindings, b->bindings, a->binding_count * sizeof(*a->bindings));
}
diff --git a/dlls/wined3d/wined3d_private.h b/dlls/wined3d/wined3d_private.h
index 5fa51a844ac..c9d83b3fbc7 100644
--- a/dlls/wined3d/wined3d_private.h
+++ b/dlls/wined3d/wined3d_private.h
@@ -447,6 +447,11 @@ static inline unsigned int wined3d_popcount(unsigned int x)
#endif
}
+static inline int wined3d_uint32_compare(uint32_t x, uint32_t y)
+{
+ return (x > y) - (x < y);
+}
+
#define ORM_BACKBUFFER 0
#define ORM_FBO 1
--
2.30.2
More information about the wine-devel
mailing list