powerpc: use float64 for frsqrte
Remove the code that reduce the result to float32 as the frsqrte instruction is defined to return a double-precision estimate of the reciprocal square root. Although reducing the fractional part is harmless (as the estimation must have at least 12 bits of precision according to the old PEM), reducing the exponent range is not correct. Signed-off-by: Tristan Gingold <gingold@adacore.com> Signed-off-by: Alexander Graf <agraf@suse.de>
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@ -977,7 +977,6 @@ uint64_t helper_fres(CPUPPCState *env, uint64_t arg)
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uint64_t helper_frsqrte(CPUPPCState *env, uint64_t arg)
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uint64_t helper_frsqrte(CPUPPCState *env, uint64_t arg)
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{
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{
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CPU_DoubleU farg;
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CPU_DoubleU farg;
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float32 f32;
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farg.ll = arg;
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farg.ll = arg;
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@ -991,8 +990,6 @@ uint64_t helper_frsqrte(CPUPPCState *env, uint64_t arg)
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}
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}
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farg.d = float64_sqrt(farg.d, &env->fp_status);
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farg.d = float64_sqrt(farg.d, &env->fp_status);
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farg.d = float64_div(float64_one, farg.d, &env->fp_status);
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farg.d = float64_div(float64_one, farg.d, &env->fp_status);
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f32 = float64_to_float32(farg.d, &env->fp_status);
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farg.d = float32_to_float64(f32, &env->fp_status);
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}
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}
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return farg.ll;
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return farg.ll;
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}
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}
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