diff options
Diffstat (limited to 'kernel/yosys.cc')
| -rw-r--r-- | kernel/yosys.cc | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/yosys.cc b/kernel/yosys.cc index 20d972150..377572fc2 100644 --- a/kernel/yosys.cc +++ b/kernel/yosys.cc @@ -151,14 +151,16 @@ void yosys_banner() int ceil_log2(int x) { +#if defined(__GNUC__) + return x > 1 ? (8*sizeof(int)) - __builtin_clz(x-1) : 0; +#else if (x <= 0) return 0; - for (int i = 0; i < 32; i++) if (((x-1) >> i) == 0) return i; - log_abort(); +#endif } std::string stringf(const char *fmt, ...) |