yf13 commented on code in PR #20996:
URL: https://github.com/apache/nuttx/pull/20996#discussion_r4396097918
##########
include/nuttx/lib/math32.h:
##########
@@ -208,136 +208,135 @@ extern "C"
*/
# ifdef up_umul64_const
-# define umul64_const(res, m, n, bias) \
- (res) = up_umul64_const(m, n, bias)
+# define umul64_const(m, n, bias) up_umul64_const(m, n, bias)
# else
-# define umul64_const(res, m, n, bias) \
- do \
- { \
- uint32_t __m_lo = (m) & 0xffffffff; \
- uint32_t __m_hi = (m) >> 32; \
- uint32_t __n_lo = (n) & 0xffffffff; \
- uint32_t __n_hi = (n) >> 32; \
- uint32_t __res_lo; \
- uint32_t __res_hi; \
- uint32_t __tmp; \
- \
- if (!(bias)) \
- { \
- (res) = ((uint64_t)__m_lo * __n_lo) >> 32; \
- } \
- else if (!((m) & ((1ULL << 63) | (1ULL << 31)))) \
- { \
- (res) = ((m) + (uint64_t)__m_lo * __n_lo) >> 32; \
- } \
- else \
- { \
- (res) = (m) + (uint64_t)__m_lo * __n_lo; \
- __res_lo = (res) >> 32; \
- __res_hi = (__res_lo < __m_hi); \
- (res) = __res_lo | ((uint64_t)__res_hi << 32); \
- } \
- \
- if (!((m) & ((1ULL << 63) | (1ULL << 31)))) \
- { \
- (res) += (uint64_t)__m_lo * __n_hi; \
- (res) += (uint64_t)__m_hi * __n_lo; \
- (res) >>= 32; \
- } \
- else \
- { \
- (res) += (uint64_t)__m_lo * __n_hi; \
- __tmp = (res) >> 32; \
- (res) += (uint64_t)__m_hi * __n_lo; \
- __res_lo = (res) >> 32; \
- __res_hi = (__res_lo < __tmp); \
- (res) = __res_lo | ((uint64_t)__res_hi << 32); \
- } \
- \
- (res) += (uint64_t)__m_hi * __n_hi; \
- } \
- while (0)
+static inline_function uint64_t umul64_const(uint64_t m, uint64_t n,
+ int bias)
+{
+ uint32_t m_lo = (m) & 0xffffffff;
+ uint32_t m_hi = (m) >> 32;
+ uint32_t n_lo = (n) & 0xffffffff;
+ uint32_t n_hi = (n) >> 32;
+ uint32_t res_lo;
+ uint32_t res_hi;
+ uint32_t tmp;
+ uint64_t res;
+
+ if (!(bias))
+ {
+ res = ((uint64_t)m_lo * n_lo) >> 32;
+ }
+ else if (!((m) & ((1ULL << 63) | (1ULL << 31))))
+ {
+ res = ((m) + (uint64_t)m_lo * n_lo) >> 32;
+ }
+ else
+ {
+ res = (m) + (uint64_t)m_lo * n_lo;
+ res_lo = res >> 32;
+ res_hi = (res_lo < m_hi);
+ res = res_lo | ((uint64_t)res_hi << 32);
+ }
+
+ if (!((m) & ((1ULL << 63) | (1ULL << 31))))
+ {
+ res += (uint64_t)m_lo * n_hi;
+ res += (uint64_t)m_hi * n_lo;
+ res >>= 32;
+ }
+ else
+ {
+ res += (uint64_t)m_lo * n_hi;
+ tmp = res >> 32;
+ res += (uint64_t)m_hi * n_lo;
+ res_lo = res >> 32;
+ res_hi = (res_lo < tmp);
+ res = res_lo | ((uint64_t)res_hi << 32);
+ }
+
+ res += (uint64_t)m_hi * n_hi;
+
+ return res;
+}
# endif
-# define div64_const32(n, b) \
- do \
- { \
- uint64_t ___res; \
- uint64_t ___x; \
- uint64_t ___t; \
- uint64_t ___m; \
- uint64_t ___n = (n); \
- uint32_t ___p; \
- uint32_t ___bias; \
- uint32_t ___b = (b); \
- ___p = 1 << LOG2_FLOOR(___b); \
- ___m = (~0ULL / ___b) * ___p; \
- ___m += (((~0ULL % ___b + 1) * ___p) + ___b - 1) / ___b; \
- ___x = ~0ULL / ___b * ___b - 1; \
- ___res = ((___m & 0xffffffff) * (___x & 0xffffffff)) >> 32; \
- ___t = ___res += (___m & 0xffffffff) * (___x >> 32); \
- ___res += (___x & 0xffffffff) * (___m >> 32); \
- ___t = (___res < ___t) ? (1ULL << 32) : 0; \
- ___res = (___res >> 32) + ___t; \
- ___res += (___m >> 32) * (___x >> 32); \
- ___res /= ___p; \
- if (~0ULL % (___b / (___b & -___b)) == 0) \
- { \
- ___n /= (___b & -___b); \
- ___m = ~0ULL / (___b / (___b & -___b)); \
- ___p = 1; \
- ___bias = 1; \
- } \
- else if (___res != ___x / ___b) \
- { \
- ___bias = 1; \
- ___m = (~0ULL / ___b) * ___p; \
- ___m += ((~0ULL % ___b + 1) * ___p) / ___b; \
- } \
- else \
- { \
- uint32_t ___bits = -(___m & -___m); \
- ___bits |= ___m >> 32; \
- ___bits = (~___bits) << 1; \
- if (!___bits) \
- { \
- ___p /= (___m & -___m); \
- ___m /= (___m & -___m); \
- } \
- else \
- { \
- ___p >>= LOG2_FLOOR(___bits); \
- ___m >>= LOG2_FLOOR(___bits); \
- } \
- ___bias = 0; \
- } \
- umul64_const(___res, ___m, ___n, ___bias); \
- \
- ___res /= ___p; \
- (n) = ___res; \
- } \
- while (0)
-
-#if defined(CONFIG_HAVE_EXPRESSION_STATEMENT)
-# define div64_const(n, base) \
- ({ \
- uint64_t __n = (n); \
- uint32_t __base = (base); \
- if (IS_POWER_OF_2(__base)) \
- { \
- (__n) >>= LOG2_FLOOR(__base); \
- } \
- else if (UINTPTR_MAX == UINT32_MAX) \
- { \
- div64_const32(__n, __base); \
- } \
- else \
- { \
- __n /= __base; \
- } \
- __n; \
- })
+static inline_function uint64_t div64_const32(uint64_t n, uint32_t b)
+{
+ uint64_t res;
+ uint64_t x;
+ uint64_t t;
+ uint64_t m;
+ uint32_t p;
+ uint32_t bias;
+
+ p = 1 << LOG2_FLOOR(b);
+ m = (~0ULL / b) * p;
+ m += (((~0ULL % b + 1) * p) + b - 1) / b;
+ x = ~0ULL / b * b - 1;
+ res = ((m & 0xffffffff) * (x & 0xffffffff)) >> 32;
+ t = res += (m & 0xffffffff) * (x >> 32);
+ res += (x & 0xffffffff) * (m >> 32);
+ t = (res < t) ? (1ULL << 32) : 0;
+ res = (res >> 32) + t;
+ res += (m >> 32) * (x >> 32);
+ res /= p;
+
+ if (~0ULL % (b / (b & -b)) == 0)
+ {
+ n /= (b & -b);
+ m = ~0ULL / (b / (b & -b));
+ p = 1;
+ bias = 1;
+ }
+ else if (res != x / b)
+ {
+ bias = 1;
+ m = (~0ULL / b) * p;
+ m += ((~0ULL % b + 1) * p) / b;
+ }
+ else
+ {
+ uint32_t bits = -(m & -m);
+ bits |= m >> 32;
+ bits = (~bits) << 1;
+ if (!bits)
+ {
+ p /= (m & -m);
+ m /= (m & -m);
+ }
+ else
+ {
+ p >>= LOG2_FLOOR(bits);
+ m >>= LOG2_FLOOR(bits);
+ }
+
+ bias = 0;
+ }
+
+ res = umul64_const(m, n, bias);
+ res /= p;
+
+ return res;
+}
+#if defined(__GNUC__)
Review Comment:
@casaroli Thanks for the suggestion! but orginal `div_const()` and
`ltoa_invert" both drag 64bit div/mod funcs of libgcc on rv32, so keeping one
of them saves us nothing.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
