host-utils: fix ssub32/64_saturate return type and clamp direction
ssub32_saturate() and ssub64_saturate() were declared to return bool instead of int32_t/int64_t, and clamped to the wrong bound on overflow. Reviewed-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com> Cc: qemu-stable@nongnu.org Fixes: 16495533131 ("host-utils: Introduce signed saturation primitives") Reviewed-by: Pierrick Bouvier <pierrick.bouvier@oss.qualcomm.com> Link: https://lore.kernel.org/qemu-devel/20260807152241.1576334-2-brian.cain@oss.qualcomm.com Signed-off-by: Brian Cain <brian.cain@oss.qualcomm.com>
Brian Cain committed
Aug 7, 2026 at 08:22 UTC
9e96b5953e2fb619a5ad6274ebba3baee0b933c4
1 file changed
+12
-12
include/qemu/host-utils.h
+12
-12
@@ -607,10 +607,10 @@ static inline bool umul64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
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}
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/**
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- * sadd32_saturate - addition with saturation
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+ * sadd32_saturate - 32-bit signed addition with saturation
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* @x, @y: addends
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*
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- * Computes @x + @y, and saturates rathern than truncating the result.
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+ * Computes @x + @y, and saturates rather than truncating the result.
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*/
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static inline int32_t sadd32_saturate(int32_t x, int32_t y)
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{
@@ -622,10 +622,10 @@ static inline int32_t sadd32_saturate(int32_t x, int32_t y)
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}
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/**
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- * sadd64_saturate - addition with saturation
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+ * sadd64_saturate - 64-bit signed addition with saturation
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* @x, @y: addends
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*
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- * Computes @x + @y, and saturates rathern than truncating the result.
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+ * Computes @x + @y, and saturates rather than truncating the result.
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*/
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static inline int64_t sadd64_saturate(int64_t x, int64_t y)
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{
@@ -637,31 +637,31 @@ static inline int64_t sadd64_saturate(int64_t x, int64_t y)
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}
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/**
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- * ssub32_saturate - subtraction with saturation
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+ * ssub32_saturate - 32-bit signed subtraction with saturation
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* @x, @y: addends
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*
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- * Computes @x + @y, and saturates rathern than truncating the result.
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+ * Computes @x - @y, and saturates rather than truncating the result.
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*/
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-static inline bool ssub32_saturate(int32_t x, int32_t y)
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+static inline int32_t ssub32_saturate(int32_t x, int32_t y)
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{
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int32_t ret;
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if (ssub32_overflow(x, y, &ret)) {
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- ret = x < 0 ? INT32_MAX : INT32_MIN;
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+ ret = x < 0 ? INT32_MIN : INT32_MAX;
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}
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return ret;
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}
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/**
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- * ssub64_saturate - subtraction with saturation
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+ * ssub64_saturate - 64-bit signed subtraction with saturation
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* @x, @y: addends
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*
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- * Computes @x + @y, and saturates rathern than truncating the result.
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+ * Computes @x - @y, and saturates rather than truncating the result.
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*/
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-static inline bool ssub64_saturate(int64_t x, int64_t y)
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+static inline int64_t ssub64_saturate(int64_t x, int64_t y)
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{
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int64_t ret;
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if (ssub64_overflow(x, y, &ret)) {
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- ret = x < 0 ? INT64_MAX : INT64_MIN;
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+ ret = x < 0 ? INT64_MIN : INT64_MAX;
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}
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return ret;
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}