in reply to Perl 5 Optimizing Compiler, Part 4: LLVM Backend?

What is the difference between LLVM and any other modern http://msdn.microsoft.com/en-us/library/0zza0de8.aspx http://gcc.gnu.org/onlinedocs/gccint/LTO.html http://software.intel.com/sites/products/documentation/hpc/composerxe/en-us/2011Update/cpp/win/copts/common_options/option_ipo.htm compiler?

The problem with using a C compiler for JIT is it would have to be linked into the interp. Sure the opcode tree can be unrolled and runops removed, but your end result is still not better than B::CC since the exact same opcodes are being called with the same amount of cpu opcodes executing more or less.
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Re^2: Perl 5 Optimizing Compiler, Part 4: LLVM Backend?
by BrowserUk (Patriarch) on Aug 27, 2012 at 18:31 UTC

    LLVM is quite different to any other compiler.

    It (can) compiles to a platform-independent Intermediate Form (a sort of bytecode), that targets an idealised Virtua; Machine. Kind of like Java.

    That IF can then be converted to platform dependent machine code at compile time, or link time, or even runtime (JIT).

    It is extremely clever technology and quite unlike anything else you want to try and compare it to. It's well worth a read and a play.

    With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.

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