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authorTravis Staloch <twostepted@gmail.com>2021-09-14 18:26:28 -0700
committerAndrew Kelley <andrew@ziglang.org>2021-09-28 17:03:43 -0700
commitcd8d8add9153b17b4579c2e8951ac3f3f42e1bcd (patch)
tree6e140beefb38a1ae50c2006aff0e12fc2ab0ce4e
parent68050852fac6940d04e15900f135e6fc88845f9b (diff)
downloadzig-cd8d8add9153b17b4579c2e8951ac3f3f42e1bcd.tar.gz
zig-cd8d8add9153b17b4579c2e8951ac3f3f42e1bcd.zip
sat-arithmetic: fix shl methods in cbe
-rw-r--r--src/link/C/zig.h16
1 files changed, 10 insertions, 6 deletions
diff --git a/src/link/C/zig.h b/src/link/C/zig.h
index cb23492490..5c9d750729 100644
--- a/src/link/C/zig.h
+++ b/src/link/C/zig.h
@@ -428,17 +428,21 @@ zig_mul_sat_s(int, int, long)
zig_mul_sat_s(long, long, long long)
#define zig_shl_sat_u(ZT, T, bits) static inline T zig_shls_##ZT(T x, T y, T max) { \
- T leading_zeros = __builtin_clz(x); \
- return (leading_zeros + y > bits) ? max : x << y; \
+ if(x == 0) return 0; \
+ T bits_set = 64 - __builtin_clzll(x); \
+ return (bits_set + y > bits) ? max : x << y; \
}
#define zig_shl_sat_s(ZT, T, bits) static inline T zig_shls_##ZT(T x, T y, T min, T max) { \
- T leading_zeros = __builtin_clz(x & ~max); \
- return (leading_zeros + y > bits) ? max : x << y; \
+ if(x == 0) return 0; \
+ T x_twos_comp = x < 0 ? -x : x; \
+ T bits_set = 64 - __builtin_clzll(x_twos_comp); \
+ T min_or_max = (x < 0) ? min : max; \
+ return (y + bits_set > bits ) ? min_or_max : x << y; \
}
-zig_shl_sat_u(u8, uint8_t, 8)
-zig_shl_sat_s(i8, int8_t, 7)
+zig_shl_sat_u(u8, uint8_t, 8)
+zig_shl_sat_s(i8, int8_t, 7)
zig_shl_sat_u(u16, uint16_t, 16)
zig_shl_sat_s(i16, int16_t, 15)
zig_shl_sat_u(u32, uint32_t, 32)