as: MIPS FP ABI Selection

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1 9.27.9.3 Automatic selection of FP ABI
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1 In order to simplify and add safety to the process of selecting the
1 correct floating-point ABI, the assembler will automatically infer the
1 correct '.gnu_attribute 4, N' directive based on command line options
1 and '.module' overrides.  Where an explicit '.gnu_attribute 4, N'
1 directive has been seen then a warning will be raised if it does not
1 match an inferred setting.
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1    The floating-point ABI is inferred as follows.  If '-msoft-float' has
1 been used the module will be marked as soft-float.  If '-msingle-float'
1 has been used then the module will be marked as single-precision.  The
1 remaining ABIs are then selected based on the FP register width.
1 Double-precision is selected if the width of GP and FP registers match
1 and the special double-precision variants for 32-bit ABIs are then
1 selected depending on '-mfpxx', '-mfp64' and '-mno-odd-spreg'.
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