In the BINARY_ADD opcode, and in most arithmetic opcodes, there is a line that checks for overflow that looks like this:

if ((i^a) < 0 && (i^b) < 0) goto slow_add;

I got a small speedup by replacing this with a macro defined thusly:

#if defined(_MSC_VER) and defined(_M_IX86) #define IF_OVERFLOW_GOTO(X) __asm { jo X }; #else #define IF_OVERFLOW_GOTO(X) if ((i^a) < 0 && (i^b) < 0) goto X; #endif

Would this case be an acceptable use of snippets of inline assembler?

I'd personally be more comfortable if we didn't go down that road; there are compilers that don't support asm's (e.g. the Intel Linux compilers).