Hi Arnaud,
On 12/11/15 12:06, Arnaud Charlet wrote:
This change refines the use of the "volatile hammer" to implement the advice
given in RM 13.3(19) by disabling it for object overlays altogether. relying
instead on the ref-all aliasing property of reference types to achieve the
desired effect.
This will generate better code for object overlays, for example the following
function should now make no memory accesses at all on 64-bit platforms when
compiled at -O2 or above:
this is great! When doing tricks to improve performance I've several times
resorted to address overlays, forgetting about the "volatile hammer", only to
rediscover it for the N'th time due to the poor performance and the horrible
code generated.
Best wishes, Duncan.
