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D.gnu - Cross module inlining in runtime

 I have porting the runtime/phobos asms to gcc asm on my to-do list, will
 try to get to that within two weeks. What would be the preferred way - 
 version() guards? if yes - what version? Or would you prefer replacing
 the asms, if the changes are not going to be merged upstream anyway?

So i decided to start with this today. As i have a case where turning on logging increases a programs run time from seconds to hours, while it spends most of the time in the GC, thought gcbits would be a good place to start. But after adding gdc asm support to GCBits.testClear() the only thing that changed was this: XXXXXXXX <uint gc.gcbits.GCBits.testClear(uint)>: push %eRX mov %eRX,%eRX mov XX(%eRX),%eRX - push %eRX - mov %eRX,%eRX - shr $0x5,%eRX - lea XX(,%eRX,4),%eRX - mov XX(%eRX),%eRX - add (%eRX),%eRX - mov $0x1,%eRX - shl %Rl,%eRX - mov %eRX,%eRX mov (%eRX),%eRX - not %eRX - and %eRX,%eRX - and %eRX,%eRX - mov %eRX,(%eRX) - pop %eRX + mov XX(%eRX),%eRX + btr %eRX,XX(%eRX) + sbb %eRX,%eRX pop %eRX ret OK, the function turned into ~ three instructions, good, but why didn't it then get inlined into any of the callers? Trying to force things with an attribute turned up this: ../../../libphobos/gc/gcx.d: In member function 'gc.gcx.Gcx.fullcollect': BUILD32/gdc/dev/gcc-4.6.1/libphobos/gc/gcbits.d:119:0: sorry, unimplemented: inlining failed in call to 'testClear': function body not available ../../../libphobos/gc/gcx.d:2647:0: sorry, unimplemented: called from here BUILD32/gdc/dev/gcc-4.6.1/libphobos/gc/gcbits.d:119:0: sorry, unimplemented: inlining failed in call to 'testClear': function body not available ../../../libphobos/gc/gcx.d:2729:0: sorry, unimplemented: called from here make[3]: *** [gc/gcx.o] Error 1 Any way to make this work? Much of the asm gains will be lost when the code isn't inlined. artur
Jan 10 2012