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[Patch, microblaze]: Adjustments to pcmp instruction generation

Adjustments to pcmp instruction generation

avoid pcmpe insns when not valuable

For pure in and equality comparisions, xor is better,
Xor is a one cycle insn as pcmp.

Pattern insns will still be used when you need to
conditionally set something to one or zero, e.g

if (a)
  return 1;
  return 0;

Define contraint for first operand in insn matching
fcmp as general register

Add a constraint to the cstoresf pattern forcing the use of
general regs for the operands. This avoids an ICE where the
compiler would crash on late usage of pseudo registers.


2013-02-11  Edgar E. Iglesias <>

  * config/microblaze/microblaze.c (microblaze_emit_compare):
     Use xor for EQ/NE comparisions
  * config/microblaze/ (cstoresf4): Add constraints
     (cbranchsf4): Adjust operator to comparison_operator

Attachment: 0009-microblaze-Adjustments-to-pcmp-instruction-generatio.patch
Description: 0009-microblaze-Adjustments-to-pcmp-instruction-generatio.patch

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