diff options
Diffstat (limited to 'backends/cxxrtl/cxxrtl.h')
| -rw-r--r-- | backends/cxxrtl/cxxrtl.h | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/backends/cxxrtl/cxxrtl.h b/backends/cxxrtl/cxxrtl.h index 59393e415..3c315c7df 100644 --- a/backends/cxxrtl/cxxrtl.h +++ b/backends/cxxrtl/cxxrtl.h @@ -41,18 +41,29 @@ #include <backends/cxxrtl/cxxrtl_capi.h> +#ifndef __has_attribute +# define __has_attribute(x) 0 +#endif + // CXXRTL essentially uses the C++ compiler as a hygienic macro engine that feeds an instruction selector. // It generates a lot of specialized template functions with relatively large bodies that, when inlined // into the caller and (for those with loops) unrolled, often expose many new optimization opportunities. // Because of this, most of the CXXRTL runtime must be always inlined for best performance. -#ifndef __has_attribute -# define __has_attribute(x) 0 -#endif #if __has_attribute(always_inline) #define CXXRTL_ALWAYS_INLINE inline __attribute__((__always_inline__)) #else #define CXXRTL_ALWAYS_INLINE inline #endif +// Conversely, some functions in the generated code are extremely large yet very cold, with both of these +// properties being extreme enough to confuse C++ compilers into spending pathological amounts of time +// on a futile (the code becomes worse) attempt to optimize the least important parts of code. +#if __has_attribute(optnone) +#define CXXRTL_EXTREMELY_COLD __attribute__((__optnone__)) +#elif __has_attribute(optimize) +#define CXXRTL_EXTREMELY_COLD __attribute__((__optimize__(0))) +#else +#define CXXRTL_EXTREMELY_COLD +#endif // CXXRTL uses assert() to check for C++ contract violations (which may result in e.g. undefined behavior // of the simulation code itself), and CXXRTL_ASSERT to check for RTL contract violations (which may at |