Oh! Thanks for the quick response, Jakub. Regards, Vivek Kinhekar
-----Original Message----- From: Jakub Jelinek <[email protected]> Sent: Friday, April 13, 2018 7:08 PM To: Vivek Kinhekar <[email protected]> Cc: Alexander Monakov <[email protected]>; [email protected] Subject: Re: GCC Compiler Optimization ignores or mistreats MFENCE memory barrier related instruction On Fri, Apr 13, 2018 at 01:34:21PM +0000, Vivek Kinhekar wrote: > Hello Alexander, > > In the given testcase, the generated fdivrs instruction performs the > division of a symbol ref (memory value) by FPU Stack Register and > stores the value in FPU Stack Register. The stack registers are not memory. > Please find the following RTL Dump of the fdivrs instruction generated. > It clearly access the memory for read access! That is a constant read, that doesn't count either. It is in memory only because the instruction doesn't support constant immediates, the memory is read-only. Jakub
