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why are multiply-accumulate insns not used when -mfp32 on mips


HI:
   found mult-acc insns like madd.s/d are only used when -mfp64 is specified,
as to codes, there macros defined as:

#define ISA_HAS_FP4		((ISA_MIPS4				\
				  || (ISA_MIPS32R2 && TARGET_FLOAT64)   \    <------only float 64
				  || ISA_MIPS64				\
				  || ISA_MIPS64R2)			\
				 && !TARGET_MIPS16)

#define ISA_HAS_FP_MADD4_MSUB4  ISA_HAS_FP4

why not use madd when fp32? Is there anything special with fp32?

any clarification? Thanks very much

-- 
Best Regards.


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