AIUI compilers treat inline ASM as an entirely opaque block they cannot mutate or assume much about, so if you're inlining 100 lines of ASM, you will get the AS

AIUI compilers treat inline ASM as an entirely opaque block they cannot mutate or assume much about, so if you're inlining 100 lines of ASM, you will get the ASM you asked for, for better or worse. (Treating it as completely opaque is, I believe, also why you can get away with things like inlining AVX2 ASM on an -mno-avx2 build, for example.)