[PATCH] include/qemu/host-utils: Remove unused code in the *_overflow wrappers

[PATCH] include/qemu/host-utils: Remove unused code in the *_overflow wrappers

[Thomas Huth]

According to commit cec07c0b612975 the code in the #else paths was required
for GCC < 5.0 and Clang < 3.8. We don't support such old compilers
at all anymore, so we can remove these lines now. We keep the wrapper
function, though, since they are easier to read and help to make sure that
the parameters have the right types.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 include/qemu/host-utils.h | 65 ---------------------------------------
 1 file changed, 65 deletions(-)

diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h
index bc743f5e32..29f3a99878 100644
--- a/include/qemu/host-utils.h
+++ b/include/qemu/host-utils.h
@@ -376,12 +376,7 @@ static inline uint64_t uabs64(int64_t v)
  */
 static inline bool sadd32_overflow(int32_t x, int32_t y, int32_t *ret)
 {
-#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
     return __builtin_add_overflow(x, y, ret);
-#else
-    *ret = x + y;
-    return ((*ret ^ x) & ~(x ^ y)) < 0;
-#endif
 }
 
 /**
@@ -394,12 +389,7 @@ static inline bool sadd32_overflow(int32_t x, int32_t y, int32_t *ret)
  */
 static inline bool sadd64_overflow(int64_t x, int64_t y, int64_t *ret)
 {
-#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
     return __builtin_add_overflow(x, y, ret);
-#else
-    *ret = x + y;
-    return ((*ret ^ x) & ~(x ^ y)) < 0;
-#endif
 }
 
 /**
@@ -412,12 +402,7 @@ static inline bool sadd64_overflow(int64_t x, int64_t y, int64_t *ret)
  */
 static inline bool uadd32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
 {
-#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
     return __builtin_add_overflow(x, y, ret);
-#else
-    *ret = x + y;
-    return *ret < x;
-#endif
 }
 
 /**
@@ -430,12 +415,7 @@ static inline bool uadd32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
  */
 static inline bool uadd64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
 {
-#if __has_builtin(__builtin_add_overflow) || __GNUC__ >= 5
     return __builtin_add_overflow(x, y, ret);
-#else
-    *ret = x + y;
-    return *ret < x;
-#endif
 }
 
 /**
@@ -449,12 +429,7 @@ static inline bool uadd64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
  */
 static inline bool ssub32_overflow(int32_t x, int32_t y, int32_t *ret)
 {
-#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
     return __builtin_sub_overflow(x, y, ret);
-#else
-    *ret = x - y;
-    return ((*ret ^ x) & (x ^ y)) < 0;
-#endif
 }
 
 /**
@@ -468,12 +443,7 @@ static inline bool ssub32_overflow(int32_t x, int32_t y, int32_t *ret)
  */
 static inline bool ssub64_overflow(int64_t x, int64_t y, int64_t *ret)
 {
-#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
     return __builtin_sub_overflow(x, y, ret);
-#else
-    *ret = x - y;
-    return ((*ret ^ x) & (x ^ y)) < 0;
-#endif
 }
 
 /**
@@ -487,12 +457,7 @@ static inline bool ssub64_overflow(int64_t x, int64_t y, int64_t *ret)
  */
 static inline bool usub32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
 {
-#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
     return __builtin_sub_overflow(x, y, ret);
-#else
-    *ret = x - y;
-    return x < y;
-#endif
 }
 
 /**
@@ -506,12 +471,7 @@ static inline bool usub32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
  */
 static inline bool usub64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
 {
-#if __has_builtin(__builtin_sub_overflow) || __GNUC__ >= 5
     return __builtin_sub_overflow(x, y, ret);
-#else
-    *ret = x - y;
-    return x < y;
-#endif
 }
 
 /**
@@ -524,13 +484,7 @@ static inline bool usub64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
  */
 static inline bool smul32_overflow(int32_t x, int32_t y, int32_t *ret)
 {
-#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
     return __builtin_mul_overflow(x, y, ret);
-#else
-    int64_t z = (int64_t)x * y;
-    *ret = z;
-    return *ret != z;
-#endif
 }
 
 /**
@@ -543,14 +497,7 @@ static inline bool smul32_overflow(int32_t x, int32_t y, int32_t *ret)
  */
 static inline bool smul64_overflow(int64_t x, int64_t y, int64_t *ret)
 {
-#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
     return __builtin_mul_overflow(x, y, ret);
-#else
-    uint64_t hi, lo;
-    muls64(&lo, &hi, x, y);
-    *ret = lo;
-    return hi != ((int64_t)lo >> 63);
-#endif
 }
 
 /**
@@ -563,13 +510,7 @@ static inline bool smul64_overflow(int64_t x, int64_t y, int64_t *ret)
  */
 static inline bool umul32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
 {
-#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
     return __builtin_mul_overflow(x, y, ret);
-#else
-    uint64_t z = (uint64_t)x * y;
-    *ret = z;
-    return z > UINT32_MAX;
-#endif
 }
 
 /**
@@ -582,13 +523,7 @@ static inline bool umul32_overflow(uint32_t x, uint32_t y, uint32_t *ret)
  */
 static inline bool umul64_overflow(uint64_t x, uint64_t y, uint64_t *ret)
 {
-#if __has_builtin(__builtin_mul_overflow) || __GNUC__ >= 5
     return __builtin_mul_overflow(x, y, ret);
-#else
-    uint64_t hi;
-    mulu64(ret, &hi, x, y);
-    return hi != 0;
-#endif
 }
 
 /*
-- 
2.31.1

Re: [PATCH] include/qemu/host-utils: Remove unused code in the *_overflow wrappers

[Richard Henderson]

On 7/1/22 08:21, Thomas Huth wrote:
> According to commit cec07c0b612975 the code in the #else paths was required
> for GCC < 5.0 and Clang < 3.8. We don't support such old compilers
> at all anymore, so we can remove these lines now. We keep the wrapper
> function, though, since they are easier to read and help to make sure that
> the parameters have the right types.
> 
> Signed-off-by: Thomas Huth<thuth@redhat.com>
> ---
>   include/qemu/host-utils.h | 65 ---------------------------------------
>   1 file changed, 65 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~