Thanks for the suggestion. But I wish to use the stock gcc so that other people can repeat what I do. Since no standard option works, I am thinking of other tricks. Is it possible to add some "barrier" code at the end of a function so that gcc will not move any basic blocks after that? So that my real code is a single-entry single-exit region. Weiqin On 4/6/07, Andrew Haley <aph@xxxxxxxxxx> wrote:
Wei Qin writes: > I notice that gcc sometimes places the "ret" instruction in the middle > of a function, or sometimes emits multiple "ret" instructions for a > function. For some reason, I wish that my gcc emits only one "ret" at > the end of a function. Is there a gcc switch to force that without > disabling optimization? There is no standard option. There are several passes that reorder basic blocks. You'd have to find them all and disable them individually. Andrew. -- Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, UK Registered in England and Wales No. 3798903
