Richard Henderson <r...@twiddle.net> writes: > From: Peter Maydell <peter.mayd...@linaro.org> > > The code which patches x86 jump instructions assumes it can do an > unaligned write of a uint32_t. This is actually safe on x86, but it's > still undefined behaviour. We have infrastructure for doing efficient > unaligned accesses which doesn't engage in undefined behaviour, so > use it. > > This is technically fractionally less efficient, at least with gcc 4.6; > instead of one instruction: > 7b2: 89 3e mov %edi,(%rsi) > we get an extra spurious store to the stack slot: > 7b2: 89 7c 24 64 mov %edi,0x64(%rsp) > 7b6: 89 3e mov %edi,(%rsi)
Ehh? Is that gcc just being silly and putting parameters for an inline on the stack frame? > > Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> > Signed-off-by: Richard Henderson <r...@twiddle.net> <snip> Reviewed-by: Alex Bennée <alex.ben...@linaro.org> -- Alex Bennée
