I've managed to maintain bit exactness in the past, as have others. An equivalent test is 1 part in 10^4 difference in the output synthesised speech.
If you can't demonstrate equivalence after optimisation, then pls don't check in the code. - David On Tue, 2013-01-29 at 02:45 -0500, Albert Cahalan wrote: > On Tue, Jan 29, 2013 at 12:00 AM, David Rowe <[email protected]> wrote: > > > The best way is make sure the output (e.g. bit stream, decoded speech > > samples) after any optimisation is bit exact with what it was before > > optimisation. Pls demonstrate this before checking in any modified > > code. > > This is already unreliable on x86. You're at the mercy of gcc's > register allocator. If values stay in registers, you get 80-bit intermediates. > If values are spilled to the stack, you get 64-bit or 32-bit intermediates. > Unremarkable changes to nearby integer code can change code > structure, causing or preventing FPU register spills. Any change of > the compiler version will also change the FPU register spills. > > So, even if I make zero changes to anything, this standard can't be met. > It's already being violated. > > ------------------------------------------------------------------------------ > Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, > MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current > with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft > MVPs and experts. ON SALE this month only -- learn more at: > http://p.sf.net/sfu/learnnow-d2d > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnnow-d2d _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
