flat assembler
Message board for the users of flat assembler.
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nop
afaik the answer to both questions is no
afaik all potential synchronisation conflicts between cpu and fpu are handled automatically in modern processors except where exceptions are raised and flag testing instructions are involved. thats where wait or fwait is needed here for a conflict to arise the cpu would have to finish the 3rd instruction before the fpu had read the operand data of the 2nd instruction. when the fpu actually finishes the fadd instruction is not critical (except maybe for any subseqent compare instructions handled by the cpu) but at the end of the day only thorough testing of your code will prove it one way or the other |
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MazeGen
As nop said, WAIT checks for pending FP exceptions so you don't need it.
WAIT is documented well in offical processor manuals: http://x86asm.net/links/index.html#Processor-Manuals |
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mindcooler
But you still need it at compares?
Code: ficomp [ecx] (implicit wait) fstsw ax fwait sahf _________________ This is a block of text that can be added to posts you make. |
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ProphetOfDoom
Thanks for clarifying guys.
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