Files
gem5/ext/softfloat/f16_classify.c
ksco 53009f9e69 arch-riscv: Add Zfh extension
This commit adds RISC-V Zfh 1.0 (half-precision IEEE 754 binary16 floating
point) extension to gem5. Include the following commands:

* FLH / FSH
* FMADD.H / FMSUB.H / FNMSUB.H / FNMADD.H
* FADD.H / FSUB.H / FMUL.H / FDIV.H
* FSQRT.H
* FSGNJ.H / FSGNJN.H / FSGNJX.H
* FMIN.H / FMAX.H
* FCVT.S.H / FCVT.H.S
* FCVT.D.H / FCVT.H.D
* FCVT.W.H / FCVT.H.W
* FCVT.WU.H / FCVT.H.WU
* FMV.X.H / FMV.H.X
* FEQ.H / FLT.H / FLE.H
* FCLASS.H
* FCVT.L.H / FCVT.H.L
* FCVT.LU.H / FCVT.H.LU

Change-Id: Id7870fdfa1aa8b840706c3ba2cab8eeaf008880f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/60029
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
2022-05-27 01:22:31 +00:00

37 lines
1.1 KiB
C

#include <stdbool.h>
#include <stdint.h>
#include "platform.h"
#include "internals.h"
#include "specialize.h"
#include "softfloat.h"
uint_fast16_t f16_classify( float16_t a )
{
union ui16_f16 uA;
uint_fast16_t uiA;
uA.f = a;
uiA = uA.ui;
uint_fast16_t infOrNaN = expF16UI( uiA ) == 0x1F;
uint_fast16_t subnormalOrZero = expF16UI( uiA ) == 0;
bool sign = signF16UI( uiA );
bool fracZero = fracF16UI( uiA ) == 0;
bool isNaN = isNaNF16UI( uiA );
bool isSNaN = softfloat_isSigNaNF16UI( uiA );
return
( sign && infOrNaN && fracZero ) << 0 |
( sign && !infOrNaN && !subnormalOrZero ) << 1 |
( sign && subnormalOrZero && !fracZero ) << 2 |
( sign && subnormalOrZero && fracZero ) << 3 |
( !sign && infOrNaN && fracZero ) << 7 |
( !sign && !infOrNaN && !subnormalOrZero ) << 6 |
( !sign && subnormalOrZero && !fracZero ) << 5 |
( !sign && subnormalOrZero && fracZero ) << 4 |
( isNaN && isSNaN ) << 8 |
( isNaN && !isSNaN ) << 9;
}