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  1. JDK
  2. JDK-8129392

[ARM] investigate turning off GPR<-->FP spills

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      Arm32 and arm64 can spill to FP registers, thanks to this code:

      ifdef ARM
           // ARM has support for moving 64bit values between a pair of
           // integer registers and a double register
           idealreg2spillmask[Op_RegL]->OR(*idealreg2regmask[Op_RegD]);
           idealreg2spillmask[Op_RegD]->OR(*idealreg2regmask[Op_RegL]);
      #endif

      however, this increases and FP register pressure and VMOV is slower than a load or store on arm64 (and probably armv7 arm32) because of the FP pipeline.

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            • Assignee:
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              Reporter:
              dlong Dean Long
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