1. 04 Feb, 2010 1 commit
    • Simon Marlow's avatar
      Implement SSE2 floating-point support in the x86 native code generator (#594) · 335b9f36
      Simon Marlow authored
      The new flag -msse2 enables code generation for SSE2 on x86.  It
      results in substantially faster floating-point performance; the main
      reason for doing this was that our x87 code generation is appallingly
      bad, and since we plan to drop -fvia-C soon, we need a way to generate
      half-decent floating-point code.
      
      The catch is that SSE2 is only available on CPUs that support it (P4+,
      AMD K8+).  We'll have to think hard about whether we should enable it
      by default for the libraries we ship.  In the meantime, at least
      -msse2 should be an acceptable replacement for "-fvia-C
      -optc-ffast-math -fexcess-precision".
      
      SSE2 also has the advantage of performing all operations at the
      correct precision, so floating-point results are consistent with other
      platforms.
      
      I also tweaked the x87 code generation a bit while I was here, now
      it's slighlty less bad than before.
      335b9f36
  2. 15 Oct, 2009 1 commit
    • simonpj@microsoft.com's avatar
      Fix Trac #959: a long-standing bug in instantiating otherwise-unbound type variables · 388e3356
      simonpj@microsoft.com authored
          
         DO NOT MERGE TO GHC 6.12 branch
         (Reason: interface file format change.)
      
      The typechecker needs to instantiate otherwise-unconstraint type variables to
      an appropriately-kinded constant type, but we didn't have a supply of 
      arbitrarily-kinded tycons for this purpose.  Now we do.
      
      The details are described in Note [Any types] in TysPrim.  The
      fundamental change is that there is a new sort of TyCon, namely
      AnyTyCon, defined in TyCon.
      
      Ter's a small change to interface-file binary format, because the new
      AnyTyCons have to be serialised.
      
      I tided up the handling of uniques a bit too, so that mkUnique is not
      exported, so that we can see all the different name spaces in one module.
      388e3356
  3. 15 Feb, 2009 1 commit
    • Ben.Lippmeier@anu.edu.au's avatar
      NCG: Split up the native code generator into arch specific modules · b04a210e
      Ben.Lippmeier@anu.edu.au authored
        - nativeGen/Instruction defines a type class for a generic
          instruction set. Each of the instruction sets we have, 
          X86, PPC and SPARC are instances of it.
        
        - The register alloctors use this type class when they need
          info about a certain register or instruction, such as
          regUsage, mkSpillInstr, mkJumpInstr, patchRegs..
        
        - nativeGen/Platform defines some data types enumerating
          the architectures and operating systems supported by the 
          native code generator.
        
        - DynFlags now keeps track of the current build platform, and 
          the PositionIndependentCode module uses this to decide what
          to do instead of relying of #ifdefs.
        
        - It's not totally retargetable yet. Some info info about the
          build target is still hardwired, but I've tried to contain
          most of it to a single module, TargetRegs.
        
        - Moved the SPILL and RELOAD instructions into LiveInstr.
        
        - Reg and RegClass now have their own modules, and are shared
          across all architectures.
      b04a210e